United States
Environmental Protection
Agency
FLAME RETARDANTS IN PRINTED CIRCUIT BOARDS
^3100
9012B
FINAL REPORT
August 2015
EPA Publication 744-R-15-001
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Disclaimer
This document has not been through a formal external peer review process and does not
necessarily reflect all of the most recent policies of the U.S. Environmental Protection Agency
(EPA), in particular those now under development. The use of specific trade names or the
identification of specific products or processes in this document is not intended to represent an
endorsement by EPA or the U.S. government. Discussion of environmental statutes is intended
for information purposes only; this is not an official guidance document and should not be relied
upon to determine applicable regulatory requirements.
This document addresses environmental and human health issues associated with the production,
use, and disposal of Flame Resistant 4 (FR-4) printed circuit boards using current and emerging
flame retardant technologies. The report provides an evaluation of the environmental and human
health hazards associated with flame-retardant chemicals during manufacturing and use of the
FR-4 boards and a discussion and identification of end of life issues. The report also presents
experimental data from the investigation of the thermal breakdown of boards and the by-products
formed under different combustion and pyrolysis conditions. These data may provide further
insight into any issues that may arise, including possible end of life disposal issues.
For More Information
To learn more about the Design for the Environment (DfE) Flame Retardant in Printed Circuit
Board Partnership or the DfE Program, please visit the DfE Program website at:
www.epa.gov/dfe.
To obtain copies of DfE Program technical reports, pollution prevention case studies, and project
summaries, please contact:
National Service Center for Environmental Publications
U.S. Environmental Protection Agency
P.O. Box 42419
Cincinnati, OH 45242
Phone: (513)489-8190
(800)490-9198
Fax: (513)489-8695
E-mail: ncepimal@one.net
11
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Acknowledgements
This report was prepared by Abt Associates Inc. and Syracuse Research Corporation under
contract to the U.S. Environmental Protection Agency (EPA)'s Design for the Environment
(DfE) Program in the Economics, Exposure, and Technology Division of the Office of Pollution
Prevention and Toxics.
This document was produced as part of the DfE Flame Retardants in Printed Circuit Boards
Partnership under the direction of the partnership's steering committee, including: Ray Dawson,
BSEF; Lauren Heine, Clean Production Action; Art Fong, IBM; Steve Tisdale, Intel; Fern
Abrams, IPC; Mark Buczek, Supresta; Adrian Beard, Clariant and HFFREC; and Clive Davies,
Kathleen Yokes, and Melanie Adams, U.S. EPA DfE. The partnership's technical committee
also provided technical input, research, and other support. This project could not have been
completed without their participation.
The Flame Retardants in Printed Circuit Boards Partnership includes representatives from the
following organizations:
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IV
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Executive Summary
Background
In 2006, U.S. Environmental Protection Agency (EPA)'s Design for the Environment (DfE)
Program and the electronics industry convened a multi-stakeholder partnership to identify and
evaluate commercially available flame retardants in Flame Resistant 4 (FR-4) printed circuit
boards (PCBs). The majority of PCBs are classified as FR-4, indicating that they meet certain
performance criteria, as well as the VO requirements of the UL (Underwriters Laboratories) 94
flammability testing standard. Over 90 percent of FR-4 PCBs used epoxy resins containing the
reactive flame retardant tetrabromobisphenol A (TBBPA) to meet flammability standards when
the partnership was convened. Because little information existed concerning the potential
environmental and human health impacts of the materials being developed as alternatives to the
brominated epoxy resins being used in PCBs, the partnership developed information to improve
understanding of new and current materials that can be used to meet the flammability
requirements. This information was published in a 2008 draft report titled Partnership to
Evaluate Flame Retardants in Printed Circuit Boards. In addition to this written draft report,
experimental testing was conducted as part of this project to learn more about the combustion
by-products released during end-of-life disposal processes of PCBs.
In this version of the report, the hazard profiles in Chapter 4 and the accompanying methodology
were updated to ensure that most recent information was used for hazard assessment. Each
human health and environmental endpoint was evaluated using the 2011 DfE Criteria for Hazard
Assessment. The information on the physical-chemical and fate properties of the alternatives in
Table 5-2 of Chapter 5 and text in Chapter 7 were also updated. Chapter 6 was revised to
describe the results of the combustion testing experiments. Additional edits have been made
throughout the report as appropriate in response to public comments received on the 2008 draft
report.
Goal of the Partnership and This Report
The partnership, which includes members of the electronics industry, flame retardants industry,
environmental groups, academia, and others, developed the information in the report Partnership
to Evaluate Flame Retardants in Printed Circuit Boards to advance understanding of the human
health and environmental impacts of conventional and new flame-retardant materials that can
provide fire safety for PCBs. Participation of a diverse group of stakeholders has been critical to
developing the information for this partnership. The multi-stakeholder nature of the partnership
led to a report that takes into consideration many diverse viewpoints, making the project richer
both in approach and outcome.
This partnership report provides objective information that will help members of the electronics
industry more efficiently factor human health and environmental considerations into decision-
making when selecting flame retardants for PCB applications. This report can also serve as a step
toward developing a more comprehensive understanding of the human health and environmental
implications of flame-retardant chemicals by noting gaps in the existing human health and
environmental literature. For example, future studies could be directed at key human health and
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environmental toxicological endpoints that are not yet adequately characterized. Additional
testing could also be directed at improving understanding of fate and transport of flame-retardant
chemicals during the most relevant life-cycle phases.
The objective of the partnership is not to recommend a single best flame retardant for PCB
applications or to rank the evaluated flame retardants. In addition to information on
environmental and human health impacts, performance, and cost are critical in the final decision.
The information in this report could be used in decision-making frameworks that address these
critical elements. When using these flame-retardant chemical profiles, it is important to consider
other life-cycle impacts, including exposure considerations.
Fire Safety for Fainted Circuit Boards (PCBs) and Flame Retardants Evaluated
PCBs are commonly found in consumer and industrial electronic products, including computers
and mobile phones. Manufacturers commonly produce PCBs with flame-retardant chemicals to
help ensure fire safety. In 2008, the majority of PCBs produced worldwide met the VO
requirements of the UL 94 fire safety standard. This standard was usually achieved through the
use of brominated epoxy resins in which the reactive flame retardant TBBPA forms part of the
polymeric backbone of the resin. These UL 94 VO compliant boards are referred to as FR-4
boards, which must meet performance specifications as well as the fire safety standard. While
alternative flame-retardant materials are used in only a small percentage of FR-4 boards, in 2008,
the use of alternatives was increasing and additional flame-retardant chemicals and laminate
materials were under development. In 2008, TBBPA was used to make the epoxy resin base
material in more than 90 percent of FR-4 boards while alternative flame-retardant materials were
used in only 3 to 5 percent of FR-4 boards.
The partnership originally evaluated nine commercially available flame retardants or resins for
FR-4 laminate materials for PCBs: TBBPA, DOPO, Fyrol PMP, aluminum hydroxide, Exolit
OP 930, Melapur 200, silicon dioxide (amorphous and crystalline), and magnesium hydroxide.
Three reaction products of epoxy resin with flame retardants (TBBPA, DOPO, and Fyrol PMP)
were also evaluated for a total of 12 hazard profiles. These chemicals were identified through
market research and consultation with industry and iNEMI (the International Electronics
Manufacturing Initiative) as potentially viable options for PCBs. The reaction products of
TBBPA, DOPO, Fyrol PMP, and other reactive flame retardants are present during the
manufacturing process, and trace quantities may be locked in the PCB polymer matrix. Chemical
components making up less than 1 percent by weight of the flame-retardant formulation were not
considered in this assessment.
For this updated report, ten flame-retardant chemicals and resins for FR-4 laminate materials for
PCBs were evaluated. One of the alternatives from the 2008 draft report - "reaction product of
Fyrol PMP with bisphenol A, polymer with epichlorohydrin" - was not reassessed in the updated
Chapter 4 because the product is not known to be on the market. In the 2008 draft report, there
were two profiles for silicon dioxide - amorphous and crystalline; for this update, the two were
combined into one profile that accounts for the differences between the two forms. The ten
revised hazard profiles and their accompanying methodology are located in the updated Chapter
4 of the alternatives assessment report. A summary of the hazard assessment results by chemical
group are summarized in this updated executive summary.
VI
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Hazard Assessment Results
The level of available human health and environmental information varies widely by flame-
retardant chemical. Little information exists concerning many of the alternative flame-retardant
materials included in this report. TBBPA and silicon dioxide are more fully characterized. To
help address this discrepancy, and to increase the usefulness of this report, EPA used the tools
and expertise developed for the New Chemicals Program to estimate the potential impacts of
flame retardants when no experimental data were available.
Hazard profiles for the reactive flame retardant alternatives TBBPA, DOPO, and Fyrol PMP
vary; all three have High to Very High persistence. TBBPA is relatively well characterized with
empirical data while DOPO and Fyrol PMP have a limited data set and therefore many hazard
designations based on analogs, structural alerts, or estimation models. The primary hazard for
TBBPA is aquatic toxicity (High to Very High). TBBPA has Moderate potential for
bioaccumulation based on measured bioconcentration and estimated bioaccumulation factors.
Human health hazard designations for TBBPA are Low to Moderate; Moderate designations
were determined for carcinogenicity, developmental toxicity, and eye irritation. Comparatively,
DOPO has Low hazard for acute
aquatic toxicity and bioaccumulation potential but similar estimated hazards for carcinogenicity,
developmental toxicity, neurotoxicity, and eye irritation. DOPO is estimated to have Low
bioaccumulation potential due to hydrolysis in aqueous conditions. Fyrol PMP, with the least
amount of empirical data, has potential for Low to Moderate human health effects and High
aquatic toxicity. Fyrol PMP also has High potential for bioaccumulation based on presence of
low molecular weight oligomers.
The reactive flame retardant resins D.E.R. 500 Series (TBBPA-based resin) and Dow XZ-
92547 (DOPO-based resin) are poorly characterized. The hazard profiles for these alternatives
identify Low acute mammalian toxicity. A High skin sensitization designation was assigned
based on empirical data and Moderate respiratory sensitization was estimated for Dow XZ-
92547. Moderate hazard was estimated for carcinogenicity, genotoxicity, reproductive toxicity,
developmental effects, neurotoxicity, and repeated dose toxicity. Acute and chronic aquatic
toxicity are estimated to be Low for D.E.R. 500 Series; chronic aquatic toxicity is estimated to be
High for Dow XZ-92547. Bioaccumulation potential is estimated High and persistence estimated
to be Very High for both reactive flame retardant resins.
The additive flame retardant alternatives aluminum diethylphosphinate, aluminum hydroxide,
magnesium hydroxide, melamine polyphosphate, and silicon dioxide have varied hazard
designations for human health effects. The majority of the endpoints range from Very Low to
Moderate hazard with the exception of High repeated dose toxicity for silicon dioxide, which is
based upon inhalation of particles less than 10 jim in size. Aluminum diethylphosphinate has
Moderate aquatic toxicity hazard while the other four additive flame retardants have Low
designations for these endpoints. Persistence is expected to be High for all five of the additive
flame retardant alternatives and bioaccumulation potential is expected to be Low. The four
additive flame retardant alternatives that contain a metal (aluminum diethylphosphinate,
aluminum hydroxide, magnesium hydroxide, and silicon dioxide) were assigned High
persistence designations because these inorganic moieties are recalcitrant.
vn
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A hazard comparison summary table (presented below as Table ES-1 and Table ES-2) is also
presented in Chapter 4. The tables show relative hazard levels for eleven human health
endpoints, two aquatic toxicity endpoints, and two environmental fate endpoints. The tables also
highlight exposure considerations through the chemical life cycle. Selected flame retardants are
presented according to their reactive or additive nature. An explanation of EPA's chemical
assessment methodology and more detailed characteristics of the chemicals in each formulation
are presented in Chapter 4.
Life-Cycle Thinking and Exposure Considerations
In addition to evaluating chemical hazards, this partnership agreed it was important to apply life-
cycle thinking to more fully understand the potential human health and environmental impacts of
evaluated flame retardants. Human health and environmental impacts can occur throughout the
life cycle: from raw material extraction and chemical manufacturing, to laminate, PCB, and
electronic product manufacturing, to product use, and finally to the end of life of the material or
product. Factors such as occupational best practices and raw material extraction and subsequent
flame-retardant and laminate manufacturing, together with the physical and chemical properties
of the flame retardants, can serve as indicators of a chemical's likelihood to pose human health
and environmental exposure concerns. During later stages of the life cycle, from PCB
manufacturing to end-of-life, human health and environmental exposure potential is highly
dependent upon whether the flame retardant was incorporated additively or reactively into the
resin system. Chapter 5 explores the exposure considerations of these flame retardants and other
life-cycle considerations. The detailed chemical assessments in this report are focused only on
the flame-retardant chemicals. Other chemicals, such as feedstocks used to make the flame
retardants; chemicals used in manufacturing resins, laminate materials, and PCBs; and
degradation products and combustion by-products are only mentioned in the process
descriptions.
Combustion Testing Results
As part of this life-cycle thinking, the partnership decided that experimental testing of FR-4
laminates and PCB materials was necessary to better understand the potential by-products during
thermal end-of-life processes. The combustion by-products of four epoxy laminates alone and
with PCB components added were identified and compared. The four laminates tested were: a
brominated flame retardant epoxy laminate (BFR), an additive phosphorus-based flame retardant
epoxy laminate (PFR1), a reactive phosphorus-based flame retardant epoxy laminate (PFR2),
and a non-flame retardant epoxy laminate (NFR). PCB components designed for conventional
boards were provided by Seagate and combined with the laminates as homogeneous powders to
simulate a circuit board. A standard halogenated component (SH) blend and a low-halogen
component (LH) blend were created and combusted with the various laminates. The two end-of-
life processes simulated by a cone calorimeter in this testing were open burning (50 kW/m2 heat
flux) and incineration (100 kW/m2 heat flux). Halogenated dioxins and furans as well as
polyaromatic hydrocarbons (PAHs) emitted during combustion were measured using gas
chromatography-mass spectrometry. Cone calorimetry data on CO, CO2, particulate matter,
smoke, and heat release were also recorded. The results of the combustion testing, completed in
2012, are summarized here. A more detailed description of the testing methods, results, and
conclusions can be found in Chapter 6 with full study reports in the Appendices.
Vlll
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Analysis of halogenated dioxins and furans was conducted only for the BFRs because initial
testing indicated that PFR1 and PFR2 contained low levels of bromine and therefore would not
generate detectable levels of polybrominated dibenzo-p-dioxins/furans (PBDD/Fs). Detectable
levels of PBDD/Fs were emitted for all BFRs combusted. For the BFRs without components,
nearly 40 percent more PBDD/F emissions were generated in open burn conditions compared to
incineration conditions. PBDD/Fs were detected in the BFRs containing low-halogen
components but could not be quantitated in the samples containing standard halogen components
due to significant interference with the standard. Polychlorinated dibenzo-p-dioxins/furans
(PCDD/Fs) were quantified in the initial testing but could not be quantified in the final studies
due to an ineffective quality control standard.
PAH emissions were measured and detected in all laminate types. Of the laminates without
components, BFR emitted over three times the amount of PAHs of PFR1 in incineration
conditions; BFRs emitted almost three times more PAHs than PFR1 and almost two times more
PAHs than PFR2 in open burn conditions. BFR emitted over eight times more PAHs than NFR
in open burn conditions, while PFR1 and PFR2 emitted nearly three times and five times the
PAHs of the NFR, respectively. In incineration conditions, BFR1 emitted over three times the
PAHs of PFR1. Of the samples with standard halogen components in open burn conditions, BFR
generated nearly twice the amount of PAHs compared to PFR2 and PFR1; a similar emissions
trend was observed for the samples containing low-halogen components.
Data on smoke, particulate matter, CO and CO2 releases, and heat release were collected for all
laminate types. Smoke release was nearly twice as high for BFRs compared to PFR1 and PFR2
for laminates without components in both combustion scenarios. A similar trend was observed
for smoke release from laminates with standard halogen components. Particulate matter
emissions for PFR1 without components were nearly twice that of NFR in open burn conditions.
Of the samples containing standard halogen components, BFRs emitted over 25 percent more
particulate matter than PFR2; BFRs emitted over 50 percent more particulate matter than PFR2
in samples containing low-halogen components. However, particulate matter trends did not
always align with smoke release emissions. While differences in CO release between samples
were negligible, CO2 emissions varied depending on laminate type. Heat release results showed
flame retardant laminates to have lower peak heat releases compared to the non-flame retardant
laminates in open burn scenarios. In incineration conditions, the BFRs lowered heat release
compared to the NFRs. PFR1 emitted heat at levels about equal or slightly higher than the NFRs;
heat release was not measured for PFR2 in incineration conditions.
Selecting Flame Retardants for PCBs
The partnership recognizes that the human health and environmental impacts are important
factors in selecting a flame-retardant chemical or formulation to provide fire safety in a PCB.
However, the partnership also believes other factors are important, such as flame retardant
effectiveness, electrical and mechanical performance, reliability, cost, and impacts on end-of-life
emissions. These factors are discussed as considerations for selecting flame retardants in Chapter
7. While the report focuses on human health and environmental attributes of each flame-retardant
chemical, it is important to note that many of these flame-retardant chemicals must be used
together in different combinations to meet the performance specifications. It is also important to
note that performance requirements will vary depending on the use of the PCB.
IX
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In parallel with this draft assessment, industry trade groups tested alternative non-halogenated
flame retardants and found that they function equally as well as TBBPA-based circuit boards for
certain products. Performance testing for commercially available halogen-free flame-retardant
materials to determine their key electrical and mechanical properties has been the focus of
several separate but complementary projects conducted by iNEMI. This partnership worked
closely with iNEMI to develop this alternatives assessment, as well as the High Density
Packaging User Group (HDPUG). iNEMI recently conducted performance testing of halogen-
free alternatives to traditional flame-retardant PCB used in the high-reliability market segment
(e.g., servers, telecommunications, military) as well as those used by desktop and laptop
computer manufacturers. The HFR-Free High-Reliability PCB Project found that the eight
halogen-free flame-retardant laminates tested generally outperformed the traditional FR-4
laminate control. The HFR-Free Leadership Program, which assessed the feasibility of a broad
conversion to HFR-free PCB materials used by desktop and laptop computer manufacturers,
found the halogen-free flame-retardant laminates tested have electrical and thermo-mechanical
properties that meet or exceed those of brominated laminates and that laminate suppliers can
meet the demand for halogen-free flame-retardant PCB materials. HDPUG completed a project
in 2011 to build a database of existing information on halogen-free materials, including halogen-
free flame retardants - both commercially available and in research and development.l
http://hdpug.org/content/completed-projects#HalogenFree
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ES-1. Screening Level Hazard Summary for Reactive Flame-Retardant Chemicals & Resins
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion by-
products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the table.
VL = Very Low hazard L = Low hazard = Moderate hazard = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, , H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
* TBBPA has been shown to degrade under anaerobic conditions to form bisphenol A (BPA; CASRN 80-05-7). BPA has hazard designations different than TBBPA, as follows:
MODEPxATE (experimental) for reproductive, skin Sensitization and dermal irritation. § Based on analogy to experimental data for a structurally similar compound. ^The highest hazard
designation of any of the oligomers with MW < 1,000. ¥ Aquatic toxicity : EPA/DfE criteria are based in large part upon water column exposures which may not be adequate for poorly
soluble substances such as many flame retardants that may partition to sediment and particulates.
Chemical
(for full chemical name
and relevant trade
names see the
individual profiles in
Section 4.9)
CASRN
Human Health Effects
Acute Toxicity
Carcinogenicity
Genotoxicity
Reproductive
Developmental
Neurological
Repeated Dose
Skin Sensitization
Respiratory
Sensitization
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Chronic
Environ-
mental
Fate
Persistence
Bioaccumulation
Exposure Considerations
Availability of flame retardants
throughout the life cycle for reactive and
additive flame-retardant chemicals and
resins
Reactive Flame-Retardant Chemicals
Tetrabromobisphenol A
79-94-7
L
L
L*
L
L
L*
L*
VH
H
H
DOPO
35948-25-5
L
M
L
tf
M
M
L
VL
L
M
H
L
Fyrol PMP
63747-58-0
L
L^
L§
M§
M§
M§
M§
L
L
L
fl*
H*
VH
H*
Manufacture
End-of-Life of of FR ~>(
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Safe and ^
Use of ~
Electronics Manufacture
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Jk Manufacture of PCB ,
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Reactive Flame-Retardant Resins
D.E.R. 500 Series*
26265-08-7
L
M
M
M
M
M
M
H
MJ
MJ
L
L
VH
rf
Dow XZ-92547*
Confidential
L
M%
M§
M*
M*
M*
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H
MJ
VL
L
L
H
VH
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Manufacture of
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End-of-Life of ~
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XI
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ES-2. Screening Level Hazard Summary for Additive Flame-Retardant Chemicals
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion by-
products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the table.
VL = Very Low hazard L = Low hazard = Moderate hazard = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, , H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
R Recalcitrant: Substance is comprised of metallic species (or metalloids) that will not degrade, but may change oxidation state or undergo complexation processes under environmental
conditions. § Based on analogy to experimental data for a structurally similar compound. QConcern linked to direct lung effects associated with the inhalation of poorly soluble particles
less than 10 microns in diameter. A Depending on the grade or purity of amorphous silicon dioxide commercial products, the crystalline form of silicon dioxide may be present. The
hazard designations for crystalline silicon dioxide differ from those of amorphous silicon dioxide, as follows: VERY HIGH (experimental) for carcinogenicity; HIGH (experimental)
genotoxicity; MODERATE (experimental) for acute toxicity and eye irritation. ¥ Aquatic toxicity : EPA/DfE criteria are based in large part upon water column exposures which may not
be adequate for poorly soluble substances such as many flame retardants that may partition to sediment and particulates.
Chemical
(for full chemical name
and relevant trade
names see the
individual profiles in
Section 4.9)
CASRN
Human Health Effects
Acute Toxicity
Carcinogenicity
Genotoxicity
Reproductive
Developmental
Neurological
Repeated Dose
Skin Sensitization
Respiratory
Sensitization
Eye Irritation
Dermal Irritation
Aquatic
Toxicity
1
u
<
Chronic
Environ-
mental
Fate
Persistence
Bioaccumulation
Exposure Considerations
Availability of flame retardants throughout
the life cycle for reactive and additive
flame-retardant chemicals and resins
Additive Flame-Retardant Chemicals
Aluminum
Diethylphosphinate*
225789-38-8
L
L§
L
L
M§
M§
M§
L
L
VL
M
M
//*
L
Aluminum Hydroxide*
21645-51-2
L
L§
L
L§
L
M
M§
L
VL
VL
L
L
//*
L
Magnesium
Hydroxide*
1309-42-8
L
L
L
L
L
L
//*
L
Melamine
Polyphosphate1*
15541-60-3
L
M
M
H
M
M
M
L
L
VL
L
L
H
L
Silicon Dioxide
(amorphous)
7631-86-9
L§
HD
L
LA
VL
L
L
//*
L
Mar
ot
Manufacture
ofFR V.
End-of-Life of
Electronics *
Jt (Recycle, Manufa
/ Disposal) Lam
1
Sale and Use
of Electronics /
V Manufacture of PCS and 1
^- Incorporation into ••
Electronics
ufacture
Resin
i
cture of
nate
Hazard designations are based upon the component of the salt with the highest hazard designation, including the corresponding free acid or base.
xn
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Table of Contents
Executive Summary v
1 Introduction 1-1
1.1 Purpose of the Flame Retardant Alternatives Assessment 1-1
1.2 Scope of the Flame Retardant Alternatives Assessment 1-2
1.2.1 Life-Cycle Stages Considered 1-3
1.2.2 Aspects Beyond the Scope of This Assessment 1-4
2 FR-4 Laminates 2-1
2.1 Overview of FR-4 Laminates Market (Prismark, 2006) 2-2
2.2 Halogen-Free Laminate Market 2-4
2.3 Past Research Efforts 2-5
2.4 Process for Manufacturing FR-4 Laminates 2-7
2.4.1 Epoxy Resin Manufacturing 2-7
2.4.2 Laminate Manufacturing 2-9
2.5 Next Generation Research and Development 2-10
2.6 References 2-10
3 Chemical Flame Retardants for FR-4 Laminates 3-1
3.1 General Characteristics of Flame-Retardant Chemicals 3-1
3.1.1 Flame Retardant Classification 3-1
3.1.2 Flame Retardant Modes of Action 3-3
Flaming Combustion 3-3
Smoldering (Non-Flaming) Combustion 3-5
3.2 Flame-Retardant Chemicals Currently Used in FR-4 Laminates 3-5
Reactive Flame-Retardant Chemicals 3-5
Flame-Retardant Fillers 3-7
Other Chemicals 3-9
3.3 Next Generation Research and Development of Flame-Retardant Chemicals 3-9
3.4 References 3-10
4 Hazard Evaluation of Flame Retardants for Printed Circuit Boards 4-1
4.1 Toxicological and Environmental Endpoints 4-1
4.1.1 Definitions of Each Endpoint Evaluated Against Criteria 4-1
4.1.2 Criteria 4-4
4.1.3 Endpoints Characterized but Not Evaluated 4-7
4.2 Data Sources and Assessment Methodology 4-8
4.2.1 Identifying and Reviewing Measured Data 4-8
4.2.2 Hierarchy of Data Adequacy 4-10
4.2.3 Assessment of Polymers and Oligomers 4-11
4.3 Importance of Physical and Chemical Properties, Environmental Transport, and
Biodegradation 4-11
4.4 Evaluating Human Health Endpoints 4-18
4.4.1 Endpoints Characterized and Evaluated Against Criteria Based on Measured Data....
4-18
4.4.2 SAR - Application of SAR and Expert Judgment to Endpoint Criteria 4-20
4.5 Evaluating Environmental Toxicity and Fate Endpoints 4-21
4.5.1 Aquatic Toxicity 4-21
Xlll
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4.5.2 Bioaccumulation 4-23
4.5.3 Environmental Persistence 4-24
4.6 Endocrine Activity 4-26
4.7 References 4-30
4.8 Hazard Summary Table 4-32
4.9 Hazard Profiles 4-34
Tetrabromobisphenol A 4-34
DOPO 4-107
FyrolPMP 4-128
D.E.R. 500 Series 4-156
DowXZ-92547 4-187
Aluminum Diethylphosphinate 4-215
Aluminum Hydroxide 4-235
Magnesium Hydroxide 4-253
Melamine Polyphosphate 4-274
Silicon Dioxide (amorphous) 4-316
Potential Exposure to Flame Retardants and Other Life-Cycle Considerations 5-1
5.1 Potential Exposure Pathways and Routes (General) 5-4
5.2 Potential Occupational Releases and Exposures 5-8
5.2.1 Flame Retardant andEpoxy Resin Manufacturing 5-9
5.2.2 Laminate and Printed Circuit Board Manufacturing 5-12
5.2.3 Best Practices 5-15
5.3 Potential Consumer and General Population Exposures 5-15
5.3.1 Physical and Chemical Properties Affecting Exposures 5-15
5.3.2 Consumer Use and End-of-Life Analysis 5-16
5.4 Methods for Assessing Exposure 5-20
5.5 Chemical Life-Cycle Considerations 5-22
5.5.1 TBBPA 5-22
5.5.2 DOPO 5-25
5.5.3 FyrolPMP 5-27
5.5.4 Aluminum Diethylphosphinate 5-28
5.5.5 Aluminum Hydroxide 5-28
5.5.6 Magnesium Hydroxide 5-29
5.5.7 Melamine Polyphosphate 5-31
5.5.8 Silicon Dioxide 5-31
5.6 References 5-32
Combustion and Pyrolysis Testing of FR-4 Laminates 6-1
6.1 Background and Objectives 6-1
6.2 Phase 1 Methods and Results 6-3
6.3 Phase 2 6-6
6.3.1 Phase 2 Conclusions 6-7
6.3.2 Phase 2 Methods 6-9
6.3.3 Phase 2 Results 6-11
Considerations for Selecting Flame Retardants 7-1
7.1 Preferable Human Health and Environmental Attributes 7-1
7.1.1 Low Human Health Hazard 7-2
xiv
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7.1.2 Low Ecotoxi city 7-2
7.1.3 Readily Degradable: Low Persistence 7-2
7.1.4 Low Bioaccumulation Potential 7-3
7.1.5 Low Exposure Potential 7-4
7.2 Considerations for Poorly or Incompletely Characterized Chemicals 7-5
7.3 Social Considerations 7-6
7.4 Other Considerations 7-7
7.4.1 Flame Retardant Effectiveness and Reliability 7-7
7.4.2 Epoxy/Laminate Properties 7-8
7.4.3 Economic Viability 7-9
7.4.4 Smelting Practices 7-10
7.5 Moving Towards a Substitution Decision 7-11
7.6 Relevant Resources 7-12
7.6.1 Resources for State and Local Government Activities 7-12
7.6.2 Resources for EPA Regulations and Activities 7-12
7.6.3 Resources for Global Regulations 7-13
7.6.4 Resources from Industry Consortia 7-13
7.7 References 7-15
Appendix A Open-burning, Smelting, Incineration, Off-gassing of Printed Circuit Board
Materials Phase I Flow Reactor Experimental Results Final Report
Appendix B Use of Cone Calorimeter to Estimate PCDD/Fs and PBDD/Fs Emissions From
Combustion of Circuit Board Laminates
Appendix C Analysis of Circuit Board Samples by XRF
Appendix D Flame Retardant in Printed Circuit Boards Partnership: Short Summary of
Elemental Analyses
JR 22 - Br and Cl Analysis in Copper Clad Laminates - part II
ICL-IP Analysis of Laminate Boards
Analysis of Chlorine and Bromine
Appendix E Use of Cone Calorimeter to Identify Selected Polyhalogenated Dibenzo-P-
Dioxins/Furans and Polyaromatic Hydrocarbon Emissions from the Combustion
of Circuit Board Laminates
xv
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List of Acronyms and Abbreviations
ACR Acute to chronic ratio
AIM Analog Identification Methodology
ATH Aluminum trihydroxide (a.k.a. Alumina trihydrate)
BAF Bioaccumulation Factor
BAN Basel Action Network
BCF Bioconcentration factor
BFR Brominated flame retardant epoxy laminate
BPA Bisphenol A
BSEF Bromine Science and Environmental Forum
CCL Copper clad laminate
ChV Chronic value
DfE Design for the Environment
Dicy Dicyandiamide
EASE Estimation and Assessment of Substance Exposure
ECOSAR EPA's Ecological Structure Activity Relationships estimation program
EDSP Endocrine Disrupter Screening Program
EETD Economics, Exposure, and Technology Division
EHS Environmental, health, and safety
EMT Environmental Monitoring Technologies, Inc.
EPA U.S Environmental Protection Agency
EPIWIN Estimations Program Interface for Windows
EU European Union
E-waste Electronic waste
FR-4 Flame Resistant 4
GHS Globally Harmonized System of Classification and Labeling of Chemicals
GS-MS Gas chromatography-mass spectrometry
HDPUG High Density Packaging User Group
HPV High Production Volume
HSDB Hazardous Substances Data Bank
HSE Health and Safety Executive
IC2 Interstate Chemicals Clearinghouse
iNEMI International Electronics Manufacturing Initiative
IRIS Integrated Risk Information System
ISO International Organization for Standardization
Koc Sediment/soil adsorption/desorption coefficient
Kow Octanol/water partition coefficient
LER Liquid epoxy resin
LFL Lower limit of flammability
LH Low-halogen components
LOAEL Lowest observed adverse effect level
LOEC Lowest observed effect concentration
MITI Japanese Ministry of International Trade and Industry
MW Molecular weight
NES No effects at saturation
xvi
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NFR Non-flame retardant laminate
NOAEL No observed adverse effect level
NOEC No observed effect concentration
OECD Organisation for Economic Cooperation and Development
OPPT Office of Pollution Prevention and Toxics
ORD Office of Research and Development
P2 Pollution prevention
PAH Polycyclic aromatic hydrocarbon
PBDD/Fs Polybrominated dibenzo-p-dioxins/furans
PCB Printed circuit board
PCDD/Fs Polychlorinated dibenzo-p-dioxins/furans
PEC Predicted environmental concentration
PFR1 Additive phosphorus-based flame retardant epoxy laminate
PFR2 Reactive phosphorus-based flame retardant epoxy laminate
Prepreg Pre-impregnated material
PTFE Polytetrafluoroethylene
QSAR Quantitative structure activity relationship
SAR Structure activity relationship
SF Sustainable Futures
SH Standard halogen components
SMILES Simplified molecular input line entry specification
SVTC Silicon Valley Toxics Coalition
TBBPA Tetrabromobisphenol A
Td Decomposition temperature
Tg Transition temperature
TSCA Toxic Substances Control Act
UDRI University of Dayton Research Institute
UFL Upper limit of flammability
UK United Kingdom
UL Underwriters Laboratories
VECAP Voluntary Emissions Control Action Programme
XRF X-ray fluorescence
xvn
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1 Introduction
The electronics industry engaged in a multi-stakeholder partnership with the U.S. Environmental
Protection Agency (EPA)'s Design for the Environment (DfE) Program to identify and evaluate
commercially available flame retardants and their environmental, human health and safety, and
environmental fate aspects in Flame Resistant 4 (FR-4) printed circuit boards (PCBs). The
majority of PCBs are classified as FR-4, indicating that they meet certain performance criteria, as
well as the VO requirements of the UL (Underwriters Laboratories) 94 flammability testing
standard.2 For more than 90 percent of FR-4 PCBs, the UL 94 VO requirement is met by the use
of epoxy resins in which the reactive flame retardant tetrabromobisphenol A (TBBPA) forms
part of the polymeric backbone of the resin.
As of 2008, alternative flame-retardant materials were used in only 3 to 5 percent of FR-4
boards, but additional alternative flame-retardant materials are under development. Little
information existed at the time the partnership was convened concerning the potential
environmental and human health impacts of the materials that are being developed as alternatives
to the brominated epoxy resins. Environmental and human health impacts can occur throughout
the life cycle of a material, from development and manufacture, through product use, and finally
at the end of life of the material or product. In addition to understanding the potential
environmental and human health hazards associated with the reasonably anticipated use and
disposal of flame-retardant chemicals, stakeholders have expressed a particular interest in
understanding the combustion products that could be formed during certain end-of-life scenarios.
A risk assessment conducted in 2006 by the European Union did not find significant human
health risk associated with reacted TBBPA in PCBs.3 However, the potential environmental and
health impacts of exported electronic waste (e-waste) are not fully understood. A large
percentage of e-waste is sent to landfills or recycled through smelting to recover metals. An
unknown portion of the waste is recycled under unregulated conditions in certain developing
countries, and the health implications of such practices are of concern.
This report aims to increase understanding of the potential environmental and human health
impacts of PCBs throughout their life cycle. Information generated from this partnership will
contribute to more informed decisions concerning the selection and use of flame-retardant
materials and technologies and the disposal and recycling of e-waste.
1.1 Purpose of the Flame Retardant Alternatives Assessment
The partnership committee identified the overall purpose of this assessment as follows:
FR-4 refers to the base material of the printed circuit board; namely, a composite of an epoxy resin reinforced with
a woven fiberglass mat. UL 94 is an Underwriters Laboratories standard for flammability of plastic materials.
Within UL 94, VO classification entails one of the highest requirements.
3 The EU results, while noteworthy, will not form the basis of this assessment, but rather should be viewed in
conjunction with the independent conclusions drawn in this assessment.
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• To identify and evaluate current and alternative flame retardants and their environmental,
human health and safety, and environmental fate aspects in FR-4 PCBs.
• To allow industry and other stakeholders to consider environmental and human health
impacts along with cost and performance of circuit boards as they evaluate alternative
materials and technologies.
1.2 Scope of the Flame Retardant Alternatives Assessment
The partnership will incorporate life-cycle thinking into the project as it explores the potential
hazards associated with flame retardants and potential exposures throughout the life cycle of
flame retardants used in FR-4 PCBs. While the report focuses on flame retardants used in FR-4
PCBs, these flame retardants may also be applicable in a wide range of PCBs constructed of
woven fiberglass reinforced with thermoset resin.
As appropriate, the scope will include aspects of the life cycle where public and occupational
exposures could occur. For example, consideration of exposures from open burning or
incineration at the end of life will be included, as will exposures from manufacturing and use.
The following investigations were considered within the scope of the project:
• An environmental, health, and safety (EHS) assessment of commercially available flame-
retardant chemicals and fillers for FR-4 laminate materials;
• An assessment of environmental and human health endpoints (environmental endpoints
include ecotoxicity, fate, and transport);
• A review of potential life-cycle concerns; and
• Combustion testing to compare the potential by-products of concern from commercially
available FR-4 laminates and PCB materials during thermal end-of-life processes,
including open burning and incineration.
The project's scope will be limited to flame-retardant chemicals used in bare (i.e., unpopulated)
FR-4 PCBs. Other elements of PCBs (such as solder and casings) and chemicals in components
often attached to PCBs to make an electronic assembly (such as cables, capacitors, connectors,
and integrated circuits) will not be assessed.
The report is intended to provide information that will allow industry and other stakeholders to
evaluate alternatives for flame retardants in PCBs. The report is organized as follows:
• Chapter 1 (Introduction): This chapter provides background to the Flame Retardants in
Printed Circuit Boards partnership project including the purpose and scope of the
partnership and of this report.
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• Chapter 2 (FR-4 Laminates): This chapter describes the characteristics, market for, and
manufacturing process of FR-4 laminates and investigates possible next generation
developments.
• Chapter 3 (Chemical Flame Retardants for FR-4 Laminates): This chapter describes
chemical flame retardants generally, as well as those specific flame retardants used in
FR-4 laminates. The next generation of flame-retardant chemicals is also discussed.
• Chapter 4 (Hazard Evaluation of Flame Retardants for Printed Circuit Boards): This
chapter explains the chemical assessment methodology used in this report and
summarizes the assessment of hazards associated with individual chemicals.
• Chapter 5 (Potential Exposure to Flame Retardants and Other Life-cycle
Considerations): This chapter discusses reasonably anticipated exposure concerns and
identifies potential exposure pathways and routes associated with flame-retardant
chemicals during each stage of their life cycle.
• Chapter 6 (Combustion andPyrolysis Testing of FR-4 Laminates): This chapter describes
the rationale and methods for combustion and pyrolysis testing of PCB materials.
• Chapter 7 (Considerations for Selecting Flame Retardants): This chapter addresses
considerations for selecting alternative flame retardants based on environmental,
technical, and economic feasibility.
1.2.1 Life-Cycle Stages Considered
Figure 1-1 shows the life-cycle stages of a PCB and the associated potential exposure pathways
that will be examined in this report. In brief, the flame-retardant chemical is manufactured and
then incorporated, either reactively or additively, into the epoxy resin. The epoxy resin is then
applied to a woven fiberglass mat and hardened. Layers of copper foil are attached to both sides
of the reinforced resin sheet to form a laminate. Next, a PCB is manufactured by combining
several laminate layers that have had conductive pathways (i.e., circuits) etched into the copper
foil. The layers are then laminated together, and holes are drilled to connect circuits between
layers and hold certain electronic components (e.g., connectors or resistors). Once assembled,
PCBs are incorporated into various products by original equipment manufacturers. When the
product is no longer in use, there are several end-of-life pathways that the product may take:
landfilling, regulated incineration, unregulated incineration (or open burning), and recycling. All
of these life-cycle stages will be discussed in further detail in the subsequent chapters of this
report.
1-3
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Figure 1-1. Exposure Pathways Considered During the Life Cycle of a PCB
/A.
FR
building
blocks
Resin
building
blocks
_£//
Potential Routes of Exposure
— • — > Air Emissions
Solid/ Hazardous Waste
•" •" —^ Water Emissions
Combustion
Byproducts
Degradation
Byproducts
Transport occurs between (and sometimes [ rwi ' t /
within) each of these life-cycle processes.
1.2.2 Aspects Beyond the Scope of This Assessment
Although the assessment will explore hazard data associated with potential exposure scenarios,
the partnership does not intend to conduct a full risk assessment, which would require a full
exposure assessment along with the hazard assessment. Likewise, the project will not be a
complete life-cycle analysis, which inventories inputs and outputs from processes throughout the
life cycle and evaluates the environmental impacts associated with those inputs and outputs.
Process chemicals (i.e., etching or washing solutions used in manufacturing PCBs) are not
included in the scope of this assessment. Although PCBs come in many varieties, the scope of
this assessment is limited to FR-4 boards which meet the VO requirements of the UL 94 standard.
Boards of this type are used in consumer products such as computers and cell phones and make
up a large portion of the PCBs used in consumer products. The assessment may be useful beyond
FR-4 boards to the extent that the same flame retardants are used in other laminates constructed
of woven fiberglass reinforced with other thermoset resins such as phenolics.
Finally, this assessment is not a technical evaluation of key electrical and mechanical properties
of halogenated and halogen-free materials. These properties have been explored in parallel
assessments conducted by iNEMI (International Electronics Manufacturing Initiative) that are
described in greater detail in Section 2.3 and Section 7.6.4 of this report. Together, these
resources will provide information on both the performance and environmental properties of the
various materials being evaluated.
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2 FR-4 Laminates
Flame Resistant 4 (FR-4) laminates are flame-retardant systems of woven glass reinforced with
epoxy-like resin, notable for their resistance to heat, mechanical shock, solvents, and chemicals.
Unlike lower grade laminates, a finished FR-4 laminate can obtain a VO rating in the UL
(Underwriters Laboratories) 94 test, a vertical burning test for flammability. The UL 94 VO test
is typically conducted using a 5-inch by 0.5-inch test specimen (thickness may vary) (RTF
Company, 2014). The specimen is fastened vertically with a holding clamp at the top so that the
5-inch side is perpendicular to the ground (Figure 2-1). A cotton indicator is located 12 inches
below the bottom of the specimen to capture any flaming dripped particles from the specimen
(Figure 2-1). A burner flame is applied at a 45° angle to the bottom of the specimen in two
intervals. The burner is first applied for 10 seconds and is removed until all flaming stops (UL,
2014). The burner is then reapplied for an additional 10 seconds (UL, 2014). Two sets of five
specimens are tested (UL, 2014). In order to meet the UL 94 VO flammability standard: (1) the
specimens must not burn with flaming combustion for more than 10 seconds after the burner is
removed; (2) the total flaming combustion time for each set of five specimens must not be
greater than 50 seconds; (3) any flaming or glowing combustion must not burn up to the holding
clamp; (4) flaming dripped particles from the specimens must not ignite the cotton indicator; and
(5) glowing combustion must not exceed 30 seconds after the second burner flame is removed
from the specimen (UL, 2014).
Figure 2-1. UL 94 VO Experimental Setup
Cotton
Source: UL, 2014
FR-4 laminates can be categorized as (1) high glass transition temperature (Tg) FR-4 laminates,4
(2) middle Tg FR-4 laminates,5 and (3) low Tg FR-4 laminates.6 Within each of those
categories, individual FR-4 laminates are differentiated through reference to their physical
properties (e.g., rate of water absorption, flexural strength, dielectric constant, and resistance to
4 High glass transition temperature laminates have a Tg above 170°C.
5 Middle glass transition temperature laminates are usually considered to have a Tg of approximately 150°C.
6 Low glass transition temperature laminates are usually considered to have a Tg of 130°C and below.
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heat). With the introduction of halogen-free FR-4 materials,7 a similar segmentation is emerging
(e.g., high Tg halogen-free, low Tg halogen-free), leading to a multiplication of the number of
FR-4 materials available (Beard et al., 2006; Bergum, 2007). As different formulations (different
flame-retardant systems and different resin chemistries) result in different laminate properties,
there can be different materials within one class (e.g., low Tg) having different performance
(e.g., dielectrics, mechanics), thus addressing the different market needs. Such differences in
performance are not specific to halogen-free materials and may also exist among brominated
grades of the same Tg class.
2.1 Overview of FR-4 Laminates Market (Prismark, 2006)
In 2006, global printed circuit board (PCB) production exceeded $45 billion. PCBs are fabricated
using a variety of laminate materials, including laminate, pre-impregnated material, and resin-
coated copper. In 2006, $7.66 billion of laminate materials were consumed globally. Laminate
materials can be sub-segmented according to their composition, and include paper, composite,
FR-4, high Tg FR-4, and specialty products (polytetrafluoroethylene (PTFE) and high-
performance materials).
• Paper and composite laminates represent 17.1 percent of the global laminate market in
value (Figure 2-2). These materials are used as the basic interconnecting material for
consumer applications. The materials are low in cost, and their material characteristics
are adequate for use in mainly low-end consumer products.
• The workhorse laminate for the PCB industry is FR-4. In terms of value, approximately
70.4 percent of the material used in the industry is FR-4 glass-based laminate (including
high Tg and halogen-free) (Figure 2-2). This material provides a reliable and cost-
effective solution for the vast majority of designs.
• Many laminators offer halogen-free FR-4 laminate materials. These materials are
typically designed to be drop-in replacements for current halogenated materials, but they
carry a price premium. Halogen-free materials have been slowly gaining acceptance on a
regional basis.
• There are special applications that call for laminate materials with characteristics beyond
the capability of FR-4. These materials consist of special integrated circuit packaging
substrates and materials for use in wireless or high-speed digital applications, including
laminate containing bismaleimide-triazine resins, poly(p-phenylene oxide), high-
performance PTFE, and polyimide.
7 In accordance with IEC-61249-2-21, this report defines "halogen-free materials" ~~ materials that are <900ppm by
weight chlorine; <900ppm by weight bromine; and
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Figure 2-2. 2006 Global PCB Laminate Market by Supplier
Other Wngboard
23.8%
11.1%
Chang Chun /
2.0%\ §
Taiwan Union Tech \
2.7%^\^
Sumitomo Bakelite
2.6%
Park Nelco
3.3%
Mitsubishi
4.2% /
\ Nan Ya Plastics
70.8%
Isola
10.5%
/ Matsushita Electric
9.4%
\ Doosan
6.4%
/ Dongguan ShengYi
Hitachi Chemical 5.4%
4.7%
TOTAL: $7.66Bn
Wote: This market includes prepieg and RCC values.
Figure 2-3. 2006 Global PCB Laminate Market by Material Type
Special and Others
72.5%
Composite
4.
Paper
72.2%
FR-4 Halogen-Free
4.0%
FR-4
51.1%
FR-4 High Tg
75.3%
TOTAL:$7.66Bn
Note: Includ es prepreg
Global sales of laminate materials in 2006 were estimated at $7.66 billion. In terms of area
production, it is estimated that more than 420.2 million square meters of laminate was
manufactured to support the PCB industry in 2006. The distribution of laminate sales
geographically and the leading suppliers to each region are shown in Figure 2-4 and Figure 2-5.
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Figure 2-4. 2006 Regional Laminate Sales
America
6.7
Other
7.1%
Europe
6.5%
torea
11.9%
Taiwan
23.4%
TOTAL: $7.66Bn
TOTAL: $5.77Bn
Figure 2-5. 2006 Laminate Sales by Region
Other
27%
Other
31%
Isola, Park Nelco,
Rogers
73%
Isola, Matsushita,
Park Nelco
69%
Total: $0.51 Bn
Total: $0.50Bn
Japan
Asia
Other
18%
Other
36%
Hitachi Chemical,
Matsushita,
Mitsubishi
82%
Doosan, Chang Chun,
Isola, ITEQ, Kingboard,
Matsushita, Mitsubishi
NanYa Plastics, ShengYi
64%
Total: $0.88Bn
Total: $5.77Bn
2.2 Halogen-Free Laminate Market
There has been a continuous increase in the demand for halogen-free material over the past few
years. In 2003, the global halogen-free laminate market was approximately $60 million. In 2004
this market grew to $161 million, in 2005 it reached $239 million, and it is estimated at $307
million for 2006.
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Most laminate suppliers now include halogen-free materials in their portfolio. Pricing for
halogen-free laminate is still higher than conventional material by at least 10 percent, and often
by much more. Tallying the production volumes of such leading laminate manufacturers as
Hitachi Chemical, NanYa, Matsushita, ITEQ, Isola, Park Nelco, and others, Prismark has
constructed a market segmentation, shown in Figure 2-6.
Figure 2-6. 2006 Global Halogen-Free Laminate Market
Others
Doosan 5.1%
5.7%
ITEQ /-
6.4% /\ _ _
\ Matsushita
L 35.0%
/ ^^
/ \\\
Hitachi Chemical
20.7%
NanYa
27.7%
Total Market: 11.5M
2.3 Past Research Efforts
While demand for halogen-free laminates is increasing, there was a lack of information regarding
their performance and environmental impact when this partnership was convened. The
International Electronics Manufacturing Initiative (iNEMI) and the High Density Packaging User
Group (HDPUG) have taken on separate but complementary roles in helping to fill information
gaps.
iNEMI has carried out a series of projects to determine the key performance properties and the
reliability of halogen-free flame-retardant PCB materials. Each project has observed different
outcomes, with the latest findings indicating that the halogen-free flame-retardant laminates
tested have properties that meet or exceed those of traditional brominated laminates. Technology
improvements, especially those that optimize the polymer/fire retardant combinations used in
PCBs, have helped shift the baseline in regards to the performance of halogen-free flame-
retardant laminates.
In 2009, iNEMI completed a project focused on performance testing of commercially available
halogen-free materials to determine their electrical and mechanical properties. In 2008 when this
alternative assessment was first published, the list of laminate materials identified by iNEMI for
further study include nine laminate materials from seven different suppliers:
• NanYa NPG-TL and NPG-170TL
• Hitachi BE-67G(R)
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• TUC TU-742
• Panasonic R1566W
• ITEQIT140GandIT155G
• ShengyiS1155
• Supresta FR Laminate
While not in the final list for further study, the following laminates were also identified as
promising candidates by iNEMI:
• IsolaDE156andIS500
• TUC TU-862
• ITEQIT170G
• Nelco 4000-7EF
The results of the testing and evaluation of these laminate materials were made public in 2009.8
The overall conclusions from the investigation were (1) that the electrical, mechanical, and
reliability attributes of the halogen-free laminate materials tested were not equivalent to FR-4
laminates and (2) that the attributes of the halogen-free laminates tested were not equivalent
among each other (Fu et al., 2009). Due to the differences in performance and material properties
among laminates, iNEMI suggested that decision-makers conduct testing of materials in their
intended applications prior to mass product production (Fu et al., 2009).
iNEMI also conducted two follow-on projects to its HFR-free Program Report: (1) the HFR-Free
High-Reliability PCB Project and (2) the HFR-Free Leadership Program. The focus of the HFR-
Free High-Reliability PCB Project was to identify technology readiness, supply capability, and
reliability characteristics for halogen-free alternatives to traditional flame-retardant PCB
materials based on the requirements of the high-reliability market segment (e.g., servers,
telecommunications, military) (iNEMI, 2014). In general, the eight halogen-free flame-retardant
laminates tested outperformed the traditional FR-4 laminate control (Tisdale, 2013). The other
project, the HFR-Free Leadership Program, assessed the feasibility of a broad conversion to
HFR-free PCB materials by desktop and laptop computer manufacturers (Davignon, 2012). Key
electrical and thermo-mechanical properties were tested for six halogen-free flamed-retardant
laminates and three traditional FR-4 laminates. The results of the testing demonstrated that the
computer industry is ready for a transition to halogen-free flame-retardant laminates. It was
concluded that the halogen-free flame-retardant laminates tested have properties that meet or
exceed those of brominated laminates and that laminate suppliers can meet the demand for
halogen-free flame-retardant PCB materials (Davignon, 2012). A "Test Suite Methodology" was
also developed under this project that can inform flame retardant substitution by enabling
manufacturers to compare the electrical and thermo-mechanical properties of different laminates
based on testing (Davignon, 2012).
In contrast to the iNEMI project, HDPUG collected existing data on halogen-free flame-retardant
materials; no performance testing was conducted. HDPUG created a database of information on
the physical and mechanical properties of halogen-free flame-retardant materials, as well as the
environmental properties of those materials. The HDPUG project, completed in 2011, broadly
8 http://thor.inemi.org/webdownload/newsroom/Presentations/SMTA South China Aug09/HFR-
Free Report Aug09.pdf
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examined flame-retardant materials, both ones that are commercially viable and in research and
development (R&D). For more information about the database and other HDPUG halogen-free
projects, visit: http://hdpug.org/content/completed-projects#HalogenFree.
Even though they are taking on different roles, FIDPUG and iNEMI have been in contact with
each other, as well as this DfE partnership project, to ensure minimal duplication in scope. The
results of their efforts help inform companies that want to select halogen-free laminate materials.
2.4 Process for Manufacturing FR-4 Laminates
This section describes general processes for manufacturing epoxy resins and laminates. Specific
chemicals and process steps can differ between manufacturers and intended use of the product.
2.4.1 Epoxy Resin Manufacturing
The process for making brominated epoxy resins that are used to make FR-4 laminates is shown
below. Two different classes of oligomers (low molecular weight (MW) linear polymers) are in
common use. The simplest are prepared by reacting TBBPA with a "liquid epoxy resin" ("X" is
hydrogen in this case). The products (for example D.E.R. 500 Series) have an Mn (number
average MW) of 800-1,000 g/mole and contain about 20 percent bromine by weight After the
oligomers are prepared, they are dissolved in a variety of solvents such as acetone or methyl
ethyl ketone (2-butanone) to reduce the viscosity. The Mw (average MW) is typically about
2,000 g/mole. An excess of the epoxy resin is used, and therefore essentially all of the TBBPA is
converted.
Br,
X
In cases where it is desired to have an oligomer with a higher concentration of bromine, the
liquid epoxy resin (LER) is replaced with a brominated epoxy resin ("X" = Br in the above
structure). The products (D.E.R.™ 560 is a typical example) have similar MWs, but the content
of bromine is higher (about 50 percent bromine by weight). These "high-brominated" resins are
typically used when other non-brominated materials must be added to the formulation (or
"varnish").
In the past a large majority of laminate varnishes would be prepared by simply combining the 20
weight percent brominated resin with 3 percent weight "dicy" (dicyandiamide) as a curing agent,
along with additional solvent. After the solvent was removed and the laminate pressed, the
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thermoset matrix would contain about 20 percent bromine by weight. This is sufficient bromine
to allow the thermoset matrix to pass the VO performance requirements in the standard UL 94
test. The cure chemistry of dicy is very complex and poorly understood. However, it is known to
be capable of reacting with 4, 5, or even 6 epoxy groups.
"Catalysts" such as 2-methylimidazole are used to increase the cure rate. Imidazoles are not true
catalysts: they initiate polymer chains, and become covalently bound to the matrix.
A simplified representation of the final thermoset is shown below. In a properly cured laminate
all of the resin has become one molecule, meaning every atom is covalently linked into one
three-dimensional structure. This is desirable because it means that there are no teachable (or
volatile) materials that can be released during the various procedures used to make a final PCB.
Br Br polymer ^
polymer | O
OH
Br
.
OH/ \
polymer polymer
With the advent of lead-free solders that melt at higher temperatures, phenolic hardeners (in
place of dicy) are becoming more common. Such formulations typically have higher
decomposition temperatures. A common phenolic hardener is an oligomer prepared from phenol
and formaldehyde that has the structure shown below. These "novolaks" typically have 2.5 to 5.5
phenolic groups per molecule, which translates to Mns of 450 to 780 g/mole. Bisphenol A
novolak is also becoming increasingly common to boost the glass Tg.
OH OH OH
The cross-linked matrix formed in this case is represented below. The use of phenolic hardeners
in the formulation has the effect of reducing the bromine concentration in the final cured resin. In
some cases additional flame retardant is needed to meet the UL 94 VO classification. This is
typically a solid additive such as alumina trihydrate or other fillers. Other methods are to mix in
a fraction of the fully brominated resin that contains 50 percent bromine by weight. Finally,
additional TBBPA and LER can be mixed into the crosslinked matrix to increase the bromine
concentration of the final cured resin, although it is unclear how common this practice is among
epoxy resin manufacturers (Mullins, 2008).
Br
polymer
polymet polyme^
O O
This description does not cover all of the formulations used by laminate producers to meet their
product specifications. Various epoxy novolaks can be added.
The process of making epoxy resins containing alternative flame retardants is similar to the
process used for making brominated epoxy resins. In the case of phosphorus-based flame
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retardants, the epoxy resin is produced by reacting diglycidyl ether of bisphenol A or an epoxy
novolak with a stoichiometric deficiency of phosphorus flame retardant. This produces a new
resin containing both an epoxy group and covalently bound phosphorus. Alternatively, a
phosphorus-containing hardener can be prepared by condensing a phenolic compound with a
phosphorus-containing flame retardant. For example, hydroquinone can condense with
phosphorus-containing flame retardants in the presence of an oxidizing agent to give a
hydroquinone-phosphorus compound. The laminator uses this hardener in conjunction with an
epoxy resin (such as an epoxy novolak) and catalysts. A laminate can also be made halogen-free
by using solid inorganic flame retardants (or fillers) to achieve the VO requirement of the UL 94
fire safety standard. A phosphorus content of about 4 to 5 percent by weight in the laminate is
generally sufficient to achieve the VO requirement of the UL 94 fire safety standard.
2.4.2 Laminate Manufacturing
Most PCBs are composed of 1 to 16 conductive layers separated and supported by layers
(substrates) of insulating material. In a typical four-layer board design, internal layers are used to
provide power and ground connections with all other circuit and component connections made
on the top and bottom layers of the board. The more complex board designs have a large number
of layers necessary for different voltage levels, ground connections, and circuit package formats.
The basic layer of the PCB is a woven fiberglass mat embedded with a flame-resistant epoxy
resin. A layer of copper is often placed over this fiberglass/epoxy layer, using methods such as
silk screen printing, photoengraving, or PCB milling to remove excess copper. Various
conductive copper and insulating dielectric layers are then bonded into a single board structure
under heat and pressure. The layers are connected together through drilled holes called vias,
typically made with laser ablation or with tiny drill bits made of solid tungsten carbide. The
drilled holes can then be plated with copper to provide conductive circuits from one side of the
board to the other (How Products Are Made, 2006).
Next, the outer surfaces of a PCB may be printed with line art and text using silk screening. The
silk screen, or "red print," can indicate component designators, switch setting requirements, test
points, and other features helpful in assembling, testing, and servicing the circuit board. PCBs
intended for extreme environments may also be given a conformal coat made up of dilute
solutions of silicone rubber, polyurethane, acrylic, or epoxy, which is applied by dipping or
spraying after the components have been soldered. This coat will prevent corrosion and leakage
currents or shorting due to condensation.
Once printed, components can be added in one of two ways. In through-hole construction,
component leads are electrically and mechanically fixed to the board with a molten metal solder,
while in surface-mount construction, the components are soldered to pads or lands on the outer
surfaces of the PCB. The parts of the circuit board to which components will be mounted are
typically "masked" with solder in order to protect the board against environmental damage and
solder shorts. The solder itself was traditionally a tin-lead alloy, but new solder compounds are
now used to achieve compliance with the Restriction of Hazardous Substances directive in the
European Union, which restricts the use of lead. These new solder compounds include organic
surface protectant, immersion silver, and electroless nickel with immersion gold coating (Oresjo
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and Jacobsen, 2005). Tin-silver-copper alloys have also been developed, some containing small
amounts of an additional fourth element (IPC, 2005; Lasky, 2005).
After construction, the PCB's circuit connections are verified by sending a small amount of
current through test points throughout the board. The PCB is then ready to be packaged and
shipped for use (Electronic Interconnect, 2007).
2.5 Next Generation Research and Development
Most R&D is oriented around improving the performance of FR-4 laminates. For example,
manufacturers are seeking to improve the glass Tg of FR-4 laminates in order to produce
laminates better able to withstand heat. A higher Tg is generally compatible with the use of lead-
free solder, which often requires a higher soldering temperature (Thomas et al., 2005).
Manufacturers often consider Tg together with the decomposition temperature (Td) when
assembling lead-free assemblies. Td is the temperature at which material weight changes by 5
percent. Due to marketplace concerns over potential environmental impacts of TBBPA, such as
the generation of halogenated dioxins and furans during combustion, as supported by this
project's combustion testing (Chapter 6), the development of non-halogen flame retardants
(discussed in Section 3.2) has also been a priority of manufacturers. However, concerns over the
human health and environmental impact, as well as the expense and performance of laminates
containing these non-halogen flame retardants, are still an issue.
There are many types of FR-4 laminates under development that have a resin design different
from the epoxy-based construction described above. These typically include more thermally
stable inflexible structures (such as biphenyl or naphthalene groups) and/or nitrogen heterocyclic
structures (such as reacted-in triazine, oxazoline, or oxazine rings). Another alternative to epoxy
resin, polyimide resin, can be produced through condensation reactions between aromatic
dianhydrides and aromatic diamines (Morose, 2006). IF Technologies has manufactured an
aliphatic LER system produced from epoxidized plant oils and anhydrides that reduces
emissions, decreases toxicity, and replaces bisphenol A and epichlorohydrin. Other technologies
in development use substances such as keratin, soybean oil, or lignin in the manufacturing
process.
Improvements in the lamination process are also being developed. Technologies may soon
enable the formation and multi-layering at room temperature of ceramic film on resin circuit
boards, allowing for further multi-functionality, miniaturization, and cost reduction of electronic
devices (PhysOrg, 2004). Laser drilling techniques will allow for the production of smaller
microvias, which may allow for the creation of smaller circuit boards (Barclay, 2004). Lasers can
also be used for direct copper ablation, as they can quickly vaporize copper without damaging
the epoxy and glass substrate (Lange, 2005).
2.6 References
Barclay, Brewster. What Designers Should Know about LDI. Printed Circuit Design and
Manufacture [Online] 2004,
http://pcdandf.com/cms/images/stories/mag/0401/0401barclay.pdf (accessed 2007).
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Beard, A.; De Boysere, J. (Clariant). Halogen-Free Laminates: Worldwide Trends,
Driving Forces and Current Status. Circuit World 2006, 32 (2).
Bergum, E. (Isola). FR-4 Proliferation. CircuiTree 2007, (Apr).
Davignon, J. 2012. iNEMI HFR-Free PCB Materials Team Project: An Investigation to Identify
Technology Limitations Involved in Transitioning to HFR-Free PCB Materials.
http://thor.inemi.org/webdownload/Pres/APEX2012/Halogen-Free Forum/HFR-
Free PCB Materials Paper 022912.pdf (accessed July 30, 2014).
Electronic Interconnect. Manufacturer of Printed Circuit Boards (PCB).
http://www.eiconnect.com/eipcbres.aspx?type=howpcb (accessed 2007).
Fu, H.; Tisdale, S.; Pfahl, R. C. 2009. iNEMI HFR-free Program Report.
http://thor.inemi.org/webdownload/newsroom/Presentati ons/SMTA_South_China_AugO
9/HFR-Free Report Aug09.pdf (accessed July 30, 2014).
Fujitsu: World's First Technologies to Form and Multi-layer High Dielectric Constant Ceramic
Film on Resin Circuit Board. PhysOrg [Online] August 6, 2004,
http://www.physorg.com/news717.html (accessed 2007).
How Products Are Made. Printed Circuit Boards. http://www.madehow.com/Volume-2/Printed-
Circuit-Board.html (accessed 2007).
iNEMI. HFR-Free High-Reliability PCB. http://www.inemi.org/project-page/hfr-free-high-
reliability-pcb (accessed July 30, 2014).
IPC. SnAgCu. 2005. http://leadfree.ipc.org/RoHS 3-2-l-3.asp (accessed Feb 14, 2008).
Lange, Bernd. PCB Machining and Repair via Laser. OnBoard Technology 2005, (Feb), 14.
Lasky, Ron. "SAC Alloy for RoHS Compliant Solder Paste: Still on Target." Oct 7, 2005.
http://blogs.indium.com/blog/an-interview-with-the-professor/sac-alloy-for-rohs-
compliant-solder-paste-still-on-target (accessed Feb 14, 2008).
Morose, G. An Investigation of Alternatives to Tetrabromobisphenol A (TBBPA) and
Hexabromocyclododecane (HBCD). Lowell Center for Sustainable Production:
University of Massachusetts Lowell, 2006. Prepared for: The Jennifer Altman
Foundation.
Mullins, Michael. Personal communication by phone with Melanie Vrabel, April 2008.
Oresjo, S.; Jacobsen, C. Pb-Free PCB Finishes for ICT. Circuits Assembly. [Online] 2005,
http://circuitsassembly.com/cms/content/view/2278/95 (accessed 2007).
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Prismark Partners LLC. Halogen-Free PCB Laminate Materials Current Commercial Status and
Short-Term Forecast; Report No. 3371; Abt Associates: Prepared under subcontract
August 2006.
RTF Company. UL94 V-0, V-l, V-2 Flammability Standard.
http://web.rtpcompany.com/info/ul/ul94v012.htm (accessed June 30, 2014).
Tisdale, S. 2013. "BFR-Free High Reliability PCB Project Summary." Presented at the iNEMI
Sustainability Forum, APEX 2013. February 21, 2013. San Diego, CA.
http://thor.inemi.org/webdownload/Pres/APEX2013/Sustainabilitv Forum 022113.pdf
(accessed July 30, 2014).
Thomas, Samuel G. Jr. et al. Tetrabromobisphenol-A Versus Alternatives in PWBs. OnBoard
Technology 2005, (June).
UL. UL 94 Flame Rating, http://www.ides.com/property descriptions/UL94.asp (accessed June
30, 2014).
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3 Chemical Flame Retardants for FR-4 Laminates
This chapter summarizes the general characteristics of flame retardants and associated
mechanisms of flame retardancy. The flame-retardant chemicals currently used in printed circuit
boards (PCBs) are also briefly introduced, with more detailed information about their potential
exposure pathways, toxicity, and life-cycle considerations presented in later chapters.
3.1 General Characteristics of Flame-Retardant Chemicals
Fire occurs in three stages: (a) thermal decomposition, where the solid, or condensed phase,
breaks down into gaseous decomposition products as a result of heat, (b) combustion chain
reactions in the gas phase, where thermal decomposition products react with an oxidant (usually
air) and generate more combustion products, which can then propagate the fire and release heat,
and (c) transfer of the heat generated from the combustion process back to the condensed phase
to continue the thermal decomposition process (Hirschler, 1992; Beyler and Hirschler, 2002).
In general, flame retardants decrease the likelihood of a fire occurring and/or decrease the
undesirable consequences of a fire (Lyons, 1970; Cullis and Hirschler, 1981). The simplest way,
in theory, of preventing polymer combustion is to design the polymer so that it is thermally very
stable. Thermally stable polymers are less likely to thermally degrade, which prevents
combustion from initiating. However, thermally stable polymers are not typically used due to
cost and/or other performance issues such as mechanical and electrical properties incompatible
with end-use needs for the finished part/item. As a result, manufacturers use other methods, such
as using flame-retardant chemicals, to impart flame-retardant properties to polymers.
Flame retardants typically function by decreasing the release rate of heat (Hirschler, 1994), thus
reducing the burning rate or flame spread of a fire, or by reducing smoke generation (Morose,
2006). In the gas phase, flame retardants can interfere with free radical chain reactions, thereby
reducing the tendency of the fire to propagate and spread. Flame retardants can also act in the gas
phase by cooling reactants and thereby decrease the rate of combustion. In the condensed phase,
flame retardants can act by forming a solid char (or a glassy layer), which interferes with the
transfer of heat back from the gas phase to the condensed phase. This inhibits or prevents further
thermal decomposition.
Typically, flame retardants contain one of the following seven elements: chlorine, bromine,
aluminum, boron, nitrogen, phosphorus, or antimony (Lyons, 1970; Cullis and Hirschler, 1981;
Hirschler, 1982). There are, however, a number of replacements and synergists that are also
effective. For example, aluminum (which is most often used as an oxide or hydroxide) can be
replaced with magnesium hydroxide or by a magnesium salt. In addition, some elements, such as
zinc (often used as zinc borate or zinc stannate) and molybdenum (often used as ammonium
molybdates), are effective primarily as smoke suppressants in mixtures of flame retardants.
3.1.1 Flame Retardant Classification
Flame retardants are generally incorporated throughout the polymeric material, although they can
also be coated on the external surface of the polymer to form a suitable protective barrier. Flame
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retardants can be classified, broadly speaking, into two types according to the method of
incorporation:
• Reactive: Reactive flame retardants are incorporated into polymers via chemical
reactions. The production of existing polymers is modified so that one or more
unsubstituted reactant monomers is replaced with a substituted monomer containing
flame-retardant heteroelements. The substituted monomers and their heteroelement
components become an integral part of the resulting polymer structure. Reactive flame
retardants must be incorporated at an early stage of manufacturing, but once introduced
they become a permanent part of the polymer structure. Once they are chemically bound,
reactive flame-retardant chemicals cease to exist as separate chemical entities. Reactive
flame retardants have a greater effect than additive flame retardants on the chemical and
physical properties of the polymer into which they are incorporated.
• Additive: Additive flame retardants are incorporated into the compounds via physical
mixing. Compounds containing flame-retardant elements are mixed with existing
polymers without undergoing any chemical reactions. As a result, the polymer/additive
mixture is less susceptible to combustion than the polymer alone. Since additive flame
retardants can be incorporated into the product up until the final stages of manufacturing,
it is typically simpler for manufacturers to use additive flame retardants than reactive
flame retardants.
Due to the differing physical and chemical properties of flame-retardant chemicals, most are
used exclusively as either reactive or additive flame retardants. Both reactive and additive flame
retardants can significantly change the properties of the polymers into which they are
incorporated. For example, they may change the viscosity, flexibility, density, and electrical
properties, and may also increase the susceptibility of the polymers to photochemical and
thermal degradation.
Flame retardants can also be classified into four main categories according to chemical
composition (TPC, 2003; and Morose, 2006):
• Inorganic: This category includes silicon dioxide, metal hydroxides (e.g., aluminum
hydroxide and magnesium hydroxide), antimony compounds (e.g., antimony trioxide),
boron compounds (e.g., zinc borate), and other metal compounds (molybdenum trioxide).
As a group, these flame retardants represent the largest fraction of total flame retardants
in use.
• Halogenated. These flame retardants are primarily based on chlorine and bromine.
Typical halogenated flame retardants are halogenated paraffins, halogenated alicyclic and
aromatic compounds, and halogenated polymeric materials. Some halogenated flame
retardants also contain other heteroelements, such as phosphorus or nitrogen. When
antimony oxide is used, it is almost invariably used as a synergist for halogenated flame
retardants. The effectiveness of halogenated additives, as discussed below, is due to their
interference with the radical chain mechanism in the combustion process of the gas
phase. Brominated compounds represent approximately 25 percent by volume of the
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global flame retardant production (Morose, 2006). Chemically, they can be further
divided into three classes:
o Aromatic, including tetrabromobisphenol A (TBBPA), polybrominated diphenyl
ethers, and polybrominated biphenyls;
o Aliphatic; and
o Cycloaliphatic, including hexabromocyclododecane.
• Phosphorus-based: When this partnership was convened, the current information
showed that this category represented about 20 percent by volume of the global
production of flame retardants and includes organic and inorganic phosphates,
phosphonates, and phosphinates as well as red phosphorus, thus covering a wide range of
phosphorus compounds with different oxidation states. There are also halogenated
phosphate esters, often used as flame retardants for polyurethane foams or as flame-
retardant plasticizers but not commonly used in electronics applications (Hirschler, 1998;
Green, 2000; Weil, 2004).
• Nitrogen-based: These flame retardants include melamine and melamine derivatives
(e.g., melamine cyanurate, melamine polyphosphate). It is rare for flame retardants to
contain no heteroatom other than nitrogen and to be used on their own. Nitrogen-
containing flame retardants are often used in combination with phosphorus-based flame
retardants, often with both elements in the same molecule.
3.1.2 Flame Retardant Modes of Action
The burning of polymers is a complex process involving a number of interrelated and
interdependent stages. It is possible to decrease the overall rate of polymer combustion by
interfering with one or more of these stages. The basic mechanisms of flame retardancy will vary
depending on the flame retardant and polymer system.
Flaming Combustion
Chemical Inhibitors — Some flame retardants interfere with the first stage of burning, in which
the polymer undergoes thermal decomposition and releases combustible gases. Interference
during this stage alters polymer breakdown in such a way as to change either the nature of
released gases or the rate at which they are released. The resulting gas/oxidant mixture may no
longer be flammable.
Fillers - A completely different mode of action is that exerted by inert solids incorporated into
polymers. Such materials, known as fillers, absorb heat and conduct heat away by virtue of their
heat capacity and thermal conductivity, respectively. As a result, fillers keep polymers cool and
prevent them from thermally decomposing. The temperature is kept down even more effectively
if the fillers decompose endothermically. Since fillers act predominantly via a physical rather
than a chemical process, large levels of fillers are needed.
Protective Barriers - Some flame retardants cover the flammable polymer surface with a non-
flammable protective coating. The coating helps insulate the flammable polymer from the source
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of heat, thus preventing the formation of combustible breakdown products and their escape into
the gas phase. The non-flammable coating may also prevent gaseous oxidants (normally air or
oxygen) from contacting the polymer surface. Intumescent compounds, which swell as a result of
heat exposure, lead to the formation of a protective barrier in which the gaseous products of
polymer decomposition are trapped. Alternatively, a non-flammable layer can be directly applied
to the surface of the polymer to form a non-intumescent barrier coating. Many phosphorus-
containing compounds form such non-intumescent surface chars.
Gaseous Phase Mechanisms - Flame-retardant chemicals can also inhibit combustion of the
gaseous products of polymer decomposition. These reactions are known as the gaseous flame
reactions. As for condensed phase inhibition, there are several rather distinct possible modes of
action.
In some cases, flame retardants lead to the release of reactive gaseous compounds into the
combustion zone, which can replace highly active free radicals with less reactive free radicals.
The less reactive free radicals slow the combustion process and reduce flame speed. In other
cases, flame retardants can cause the evolution of a small particle "mist" during combustion.
These small particles act as "third bodies" that catalyze free-radical recombination and hence
chain termination. This mode of action is typical of halogenated flame retardants, which usually
act by decomposing at high temperature to generate hydrogen chloride or hydrogen bromide.
These compounds react with oxygenated radicals and inhibit gas phase combustion reactions
(Cullis and Hirschler, 1981; Hirschler, 1982; Georlette et al., 2000).
Flame-retardant chemicals can also operate by releasing relatively large quantities of inert gas
during decomposition, which can change the composition and temperature of gaseous polymer
decomposition products. The resulting mixture of gaseous products and surrounding gaseous
oxidants are no longer capable of propagating flame. In some systems, when the polymer burns
the flame-retardant chemical is released chemically unchanged as a heavy vapor, which
effectively "smothers" the flame by interfering with the normal interchange of combustible
gaseous polymer decomposition products and combustion air or oxygen. This mode of action is
typical of metal hydroxides, such as aluminum or magnesium hydroxide (Horn, 2000).
Melting and Dripping - Some flame-retardant chemicals inhibit combustion by interfering with
the transfer of heat from combustion back to the polymer. Certain chemicals may promote
depolymerization, which lowers the molecular weight of the polymer and facilitates melting. As
the burning melt drips away from the bulk of the polymer it carries with it a proportion of the
heat that would otherwise contribute to polymer decomposition and volatilization. By reducing
the release of volatile decomposition products into the gas phase, these flame retardants reduce
the amount of gaseous decomposition products available to feed the flame. While enhanced
melting should decrease flammability in theory, in practice droplets of burning molten polymer
may help spread a fire to other combustible materials.
Ablation — Combustion can also be retarded by coating or constructing the polymer in such a
way that, when it burns, incandescent sections disintegrate from the original polymer and remove
with them heat from the combustion zone. This mechanism of action, known as ablation, is in a
sense the solid phase parallel of liquid phase melting and dripping. A surface char layer is
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frequently formed, which isolates the bulk of the polymer material from the high temperature
environment. This charry layer remains attached to the substrate for at least a short period while
a degradation zone is formed underneath it. In this zone, the organic polymer undergoes melting,
vaporization, oxidation, or pyrolysis. The ablative performance of polymeric materials is
influenced by polymeric composition and structure, as well as environmental factors, such as
atmospheric oxygen content. Higher hydrogen, nitrogen, and oxygen content of the polymer
increases the char oxidation rate; higher carbon content decreases the char oxidation rate
(Levchik and Wilkie, 2000).
Smoldering (Non-Flaming) Combustion
Smoldering (non-flaming) combustion and the closely related phenomenon of glowing
combustion occur primarily with high-surface area polymeric materials that break down during
combustion to form a residual carbonaceous char (typically cellulosic materials). In general, it is
possible to inhibit non-flaming combustion either by retarding or preventing the initial
breakdown of the polymer to form a char, or by interfering with the further combustion of this
char. Boric acid and phosphates are the primary flame retardants used for preventing non-
flaming combustion of organic polymers.
3.2 Flame-Retardant Chemicals Currently Used in FR-4 Laminates
Over the last several years, the electronics industry has been increasingly focused on researching
and developing halogen-free alternatives to TBBPA, due in large part to environmental concerns
and the anticipation of possible regulatory actions in the European Union. Several flame-
retardant chemicals are commercially available to meet fire safety standards for Flame Resistant
4 (FR-4) laminates. As of 2008, the halogenated flame retardant TBBPA is used in
approximately 90 percent of FR-4 PCBs. The majority of halogen-free alternatives to TBBPA
are based on phosphorus compounds that are directly reacted into the epoxy resin or combined
with aluminum trioxide or other fillers (De Boysere and Dietz, 2005). This section briefly
discusses TBBPA, dihydrooxaphosphaphenanthrene (DOPO), Fyrol PMP, and four commonly
used halogen-free fillers: aluminum hydroxide, melamine polyphosphate, metal phosphinate,
and silica. In this report, these four fillers are also referred to as additive flame retardants.
Reactive Flame-Retardant Chemicals
TBBPA
Br\ /-, >< /-\ /Br
HO y y OH
Br Br
TBBPA is a crystalline solid with the chemical formula CisH^B^C^. TBBPA increases the
glass transition temperature (Tg) of the epoxy resins and enables the resin to achieve a UL
(Underwriters Laboratories) 94 VO flammability rating. TBBPA is most commonly reacted into
the epoxy resin through "chain extension," meaning TBBPA is reacted with a molar excess of
diglycidyl ether of bisphenol A, or other similar epoxy. Once the TBBPA is chemically bound,
5-5
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the finished epoxy resin typically contains about 18 to 21 percent bromine (Weil and Levchik,
2004).
TBBPA is produced by several flame retardant manufacturers. According to High Density
Packaging User Group International (2004) and Morose (2006), TBBPA's market dominance is
due primarily to its moisture resistance, thermal stability, cost-effectiveness, compatibility with
the other components of PCBs, and ability to preserve the board's physical properties. Aside
from PCBs, another primary application of TBBPA is its use as an additive flame retardant in the
acrylonitrile-butadiene-styrene resins found in electronic enclosures of televisions and other
products.
DOPO
DOPO is a hydrogenphosphinate made from o-phenyphenol and phosphorus trichloride. Similar
to TBBPA, it can be chemically reacted to become part of the epoxy resin backbone. DOPO was
originally developed as a flame retardant for polyester textile fibers and also has applications as
an antioxidant-type stabilizer (Weil and Levchik, 2004). Due to DOPO's higher cost (nearly four
times as much as TBBPA at the time this partnership was convened), its use has been limited by
laminate manufacturers. To decrease the cost of their formulations, some laminate manufacturers
are using DOPO in combination with less expensive materials such as alumina trihydrate (ATH)
and/or silica (Thomas et al., 2005) or along with more cost-effective compounds like metal
phosphinates (De Boysere and Dietz, 2005).
FyrolPMP
Fyrol PMP is an aromatic phosphonate oligomer with high phosphorus content (17 to 18
percent). Similar to TBBPA and DOPO, Fyrol PMP can be chemically reacted to become part of
the epoxy resin backbone. When reacted into a phenol-formaldehyde novolak epoxy, Fyrol PMP
provides good flame retardancy at loadings as low as 20 percent (Weil, 2004).
-------
Flame-Retardant Fillers
Aluminum Hydroxide
HCL JDH
/M
OH
While the use of aluminum hydroxide (A1(OH)3) in FR-4 PCBs was relatively low several years
ago, it was the largest volume flame retardant used worldwide, with an estimated 42 percent
volume market share in 2006 (BCC, 2006). Aluminum hydroxide is commonly referred to as
ATH and has been used to impart flame retardancy and smoke suppression in carpet backing,
rubber products, fiberglass-reinforced polyesters, cables, and other products. It is also used in the
manufacture of a variety of items - antiperspirants, toothpaste, detergents, paper, and printing
inks - and is used as an antacid.
ATH is difficult to use alone to achieve the FR-4 rating of laminates, and as a result, high
loadings relative to the epoxy resin, typically up to 60 to 70 percent by weight, are needed
(Morose, 2006). ATH is most commonly used in FR-4 PCBs as a flame-retardant filler, in
combination with DOPO or other phosphorus-based compounds. When heated to 200-220°C,
ATH begins to undergo an endothermic decomposition to 66 percent alumina and 34 percent
water (Morose, 2006). It retards the combustion of polymers by acting as a "heat sink" - i.e., by
absorbing a large portion of the heat of combustion (HDPUG, 2004).
Melamine Polyphosphate
O O
l^P^ J^P^
HO^L 0-ft| OH
O OH
H
NH2
Melamine polyphosphate, an additive-type flame retardant based on a combination of
phosphorus and nitrogen chemistries, is typically used as crystalline powder and in combination
with phosphorus-based compounds. Its volume market share in 2006 was slightly more than 1
percent (BCC, 2006) but is expected to increase as the demand for halogen-free alternatives
increases. Similar to ATH, melamine polyphosphate undergoes endothermic decomposition but
at a higher temperature (350°C). It retards combustion when the released phosphoric acid coats
and therefore forms a char around the polymer, thus reducing the amount of oxygen present at
the combustion source (Special Chem, 2007). Melamine polyphosphate does not negatively
impact the performance characteristics of standard epoxy laminates, and functions best when
blended with other non-halogen flame retardants (Kaprinidis, 2008). Melamine polyphosphate
dissociates in water to form melamine cations and phosphate anions.
5-7
-------
Metal Phosphinates
R1-
•O"
Mn4
R2'
R jn
Flame retardants based on phosphinate chemistry were a relatively new class of halogen-free
flame retardants on the market at the time this partnership was convened. One such phosphinate-
based flame retardant - aluminum diethylphosphinate - is a fine-grained powder with high
phosphorus content (23 to 24 percent) used as a filler in FR-4 laminates (De Boysere and Dietz,
2005). It is designed primarily for use in FR-4 laminate materials with Tg greater than 150°C
(mid-range and high Tg applications). Like most phosphorus-based compounds, metal
phosphinates achieve flame retardancy by forming a char barrier upon heating, thereby cutting
off access to the oxygen needed for the combustion process. Due to its low density and high
surface area, aluminum diethylphosphinate cannot be used alone. It is typically used as a
powerful synergist in combination with modified resins and sometimes other filler-type flame
retardants.
Silica
o-
0-
:sf
Also known as silicon dioxide (SiC^), silica is characterized by its abrasion resistance, electrical
insulation, and high thermal stability. Silica is not a flame retardant in the traditional sense. It
dilutes the mass of combustible components, thus reducing the amount of flame retardant
necessary to pass the flammability test. Silica is most commonly used in combination with
novolak-type epoxy resins. For example, silica clusters can be reacted with phenolic novolak
resins (the resin bonds to hydroxyl groups on the silica cluster) to form a silica-novolak hybrid
resin (Patent Storm, 2002). It can be used as an inert, low expansion material in both the epoxy
resin and electronic circuit. One drawback is its abrasiveness, which affects drilling operation
during the PCB manufacturing process.
Magnesium Hydroxide
HO-Mg-OH
Magnesium hydroxide is functionally similar to ATH, in that it endothermically decomposes at
high temperatures to produce an oxide (MgO) and water. The absorption of heat retards the
combustion of polymers, and the release of water may create a barrier that prevents oxygen from
supporting the flame (Huber, 2007). However, whereas ATH undergoes thermal decomposition
at 200-220°C, magnesium hydroxide decomposes at approximately 330°C. This allows
manufacturers to use magnesium hydroxide when processing temperatures are too high for ATH
(Morose, 2006). Similar to ATH, high loadings of magnesium hydroxide are required to achieve
-------
the FR-4 rating. In many polymer systems, in order to reduce loadings, magnesium hydroxide is
sometimes combined with more effective flame retardants, such as phosphorus (Morose, 2006).
Other Chemicals
Following is a brief description of other chemicals that can be used as flame retardants in FR-4
PCBs but are not evaluated in this paper.
Ammonium Polyphosphate
Ammonium polyphosphate is an intumescent flame retardant, meaning that it swells when
exposed to heat, and can be used in epoxies. However, it is not commonly used in electronic
applications. At high temperatures (>250°C), ammonium polyphosphate decomposes into
ammonia and polyphosphoric acid. When exposed to water, polyphosphate reacts to form
monoammonium phosphate, a fertilizer (Chemische Fabrik Budenheim, 2007).
Red Phosphorus
Red phosphorus is produced from white phosphorus by heating white phosphorus in its own
vapor to 250°C in an inert atmosphere. It is fairly stable and is used in the manufacture of several
products, such as matches, pesticides, and flame retardants (Lide, 1993; Diskowski and
Hofmann, 2005). Its main use as a flame retardant is in fiberglass-reinforced polyamides.
Although it does function in epoxy resins, it is not recommended for electronic applications,
because red phosphorus can form phosphine (PH3) and acidic oxides under hot and humid
conditions (Clariant, 2002). The oxides can lead to metal corrosion, and hence electric defects
can occur (Clariant, personal communication 2007).
Antimony Oxide
Antimony oxide, typically antimony trioxide (Sb2O3), can be used as a flame retardant in a wide
range of plastics, rubbers, paper, and textiles. Antimony trioxide does not usually act directly as
a flame retardant, but as a synergist for halogenated flame retardants. Antimony trioxide
enhances the activity of halogenated flame retardants by releasing the halogenated radicals in a
stepwise manner. This retards gas phase chain reactions associated with combustion, which
slows fire spread (Hastie and McBee, 1975; Hirschler, 1982; Chemical Land 21, 2007).
Melamine Cyanurate
Melamine cyanurate is relatively cheap and highly available. However, it is a poor flame
retardant and requires high dosage (>40 percent weight) (Albemarle, 2007).
3.3 Next Generation Research and Development of Flame-Retardant Chemicals
Some companies are already offering halogen-free alternatives to TBBPA. In 2008, JJI
Technologies, for example, is developing new activated, non-halogen flame-retardant
formulations for PCBs - both additive and reactive. An activated flame retardant is one that
provides enhanced flame retardancy through the incorporation of an activator, which may consist
of either a char-forming catalyst or phase-transfer catalyst or both. Activated flame retardants
may improve flame-retardant features, including faster generation of char, higher char yield,
5-9
-------
denser char, self-extinguishing performance, thermal insulation, and lower smoke emissions (JJI
Technologies, 2007).
In addition to halogen-free alternatives to TBBPA, flame retardant manufacturers have
beenexploring ways to achieve a VO rating in the UL 94 fire test result through the redesign of
flame-retardant chemicals and epoxy resin systems. One of the largest areas of research and
development involves the use of nanotechnology to impart flame retardancy and increased
functionality to PCBs and other electronics products. However, their technical and commercial
viability is still limited, and their future use in commercial settings remains unknown. So far,
only combinations of nano flame retardants with traditional flame retardants have met
performance requirements. In addition, these new nano-traditional flame-retardant combinations
are only usable in certain polymer systems.
One type of halogen-free nano flame retardant is being developed through the synthesis of
ethylene-vinyl acetate copolymers with nanofillers (or nanocomposites) made of modified
layered silicates (Beyer, 2005). Nanofillers are incorporated into the olefin polymer during the
polymerization process by treating the surface of the nanofiller to induce hydrophobic
tendencies. The hydrophobic nanofiller disperses in the olefin monomers, which then undergo
polymerization and trap the nanofillers (Nanocor, 2007). Nanocomposites can also incorporate
aluminum into their structures, and can be combined with additive flame retardants, such as
ATH, leading to a reduction of the total ATH content and a corresponding improvement in
mechanical properties (Beyer, 2005).
3.4 References
Albemarle. The Future Regulatory Landscape of Flame Retardants from an Industry Perspective.
In Environmentally Friendly Flame Retardants., Proceedings of the Intertech Pira
Conference, Baltimore, MD, July 19, 2007.
BCC Research. Flame Retardancy News 2006,16 (3).
Beyer, Gunter. Flame Retardancy of Nanocomposites - from Research to Technical Products. J.
Fire Sci. 2005, 23 (Jan).
Beyler, C. L.; Hirschler, M. M. Thermal Decomposition of Polymers. In SFPE Handbook of Fire
Protection Engineering, 3rd ed; DiNenno, P.J., Ed.; NFPA: Quincy, MA, 2002, 1/110-
1/131.
Chemical Land 21. Antimony Oxide.
http://www.chemicalland21.com/industrialchem/inorganic/ANTIMONY%20TRIOXIDE.
htm (accessed 2007).
Chemische Fabrik Budenheim. Halogen Free Flame Retardants and their Applications. In
Environmentally Friendly Flame Retardants, Proceedings of the Intertech Pira
Conference, Baltimore, MD, July 19, 2007.
Clariant. Exolit RP for Thermoplastics: Technical Product Information, May 2002.
3-10
-------
Clariant. New Phosphorus Flame Retardants to Meet Industry Needs. In Environmentally
Friendly Flame Retardants, Proceedings of the Intertech Pira Conference, Baltimore,
MD, July 20, 2007.
Clariant. Personal communication by email between Kathleen Yokes and Adrian Beard,
December 2007.
Cullis, C. F.; Hirschler, M. M. The Combustion of Organic Polymers; Oxford University Press:
Oxford, 1981.
De Boysere, J.; Dietz, M. Clariant. Halogen-Free Flame Retardants For Electronic Applications.
OnBoard Technology. [Online] 2005, February, http://www.onboard-
technology.com/pdf febbraio2005/020505.pdf (accessed 2007).
Diskowski H, Hofmann T (2005): Phosphorus. Wiley-VCH, Weinheim, 10.1002/14356007.al9
505. Ullmann's Encyclopedia of Industrial Chemistry, pp. 1-22.
Georlette, P.; Simons, J.; Costa, L. Chapter 8: Halogen-containing fire retardant compounds. In
Fire Retardancy of Polymeric Materials; Grand, A.F., Wilkie, C.A., Eds.; Marcel
Dekker: New York, 2000, p 245.
Green, J. Chapter 5: Phosphorus-containing flame retardants. In Fire Retardancy of Polymeric
Materials; Grand, A.F., Wilkie, C.A., Eds.; Marcel Dekker: New York, 2000, p 147.
Hastie, J. W.; McBee, C. L. In Halogenated Fire Suppressants, Proceedings of the ACS
Symposium Series 16; Gann, R.G., Ed; American Chemical Society: Washington, DC,
1975, p 118.
High Density Packaging User Group International, Inc. (HDPUG). Environmental Assessment of
Halogen-free Printed Circuit Boards. DfE Phase II; Revised Final: January 15, 2004.
Hirschler, M. M. Recent developments in flame-retardant mechanisms. In Developments in
Polymer Stabilisation; Scott, G., Ed.; Applied Science Publ: London, 1982, 5, 107-152.
Hirschler, M. M., Ed.; Fire hazard and fire risk assessment; ASTM STP 1150; Amer. Soc.
Testing and Materials: Philadelphia, PA, 1992.
Hirschler, M. M. Fire Retardance, Smoke Toxicity and Fire Hazard. Proceedings of Flame
Retardants '94, London, UK, Jan. 26-27, 1994; British Plastics Federation, Ed.;
Interscience Communications: London, UK, 1994, 225-237.
Hirschler, M. M. Fire Performance of Poly(Vinyl Chloride) - Update and Recent Developments.
Proceedings of Flame Retardants '98, London, UK, February 3-4, 1998; Interscience
Communications: London, UK, 1998, 103-123.
3-11
-------
Horn Jr., W. E. Chapter 9: Inorganic hydroxides and hydroxycarbonates: their function and use
as flame-retardant additives. In Fire Retardancy of Polymeric Materials; Grand, A.F.,
Wilkie, C.A., Eds.; Marcel Dekker: New York, 2000, p 285.
Huber Engineered Materials (2007). Magnesium hydroxide functions in the same manner as
alumina trihydrate. http://www.hubermaterials.com/magnesiumHydroxide.htm (accessed
July 2008).
JJI Technologies. Personal communication by email between Kathleen Yokes, EPA and Jose
Reyes, JJI Technologies, Nov. 28, 2007.
IPC. IPC White Paper and Technical Report on Halogen-Free Materials Used for Printed
Circuit Boards and Assemblies; IPC-WP/TR-584, April, 2003.
Kaprinidis, N.; Fuchs S. Halogen-Free Flame Retardant Systems For PCBs. OnBoard
Technology 2008, (July).
Levchik, S.; Wilkie, C. A. Chapter 6: Char formation. In Fire Retardancy of Polymeric
Materials; Grand, A.F., Wilkie, C.A., Eds.; Marcel Dekker: New York, 2000, p 171.
Lide, D. R., ed. CRC Handbook of Chemistry and Physics, 74th edition, 1993/94; CRC Press:
Boca Raton.
Lyons, J.W. The Chemistry and Use of Fire Retardants; Wiley, New York, 1970.
Morose, G. An Investigation of Alternatives to Tetrabromobisphenol A (TBBPA) and
Hexabromocyclododecane (HBCD). Lowell Center for Sustainable Production:
University of Massachusetts Lowell, March 2006. Prepared for: The Jennifer Altman
Foundation.
Nanocor. Nanomer nanoclay as flame retardation additives. In Environmentally Friendly Flame
Retardants., Proceedings of the Intertech Pira Conference, Baltimore, MD July 20, 2007.
Special Chem. Flame Retardants Center: Melamine Compounds.
http://www.specialchem4polymers.com/tc/Melamine-Flame-
Retardants/index.aspx?id=4004 (accessed 2007).
Thomas, S. G., Jr.; Hardy, M. L.; Maxwell, K. A.; Ranken, P. F. Tetrabromobisphenol-A Versus
Alternatives in PWBs. OnBoard Technology 2005, (June).
Weil, E. D. In Flame Retardancy of Polymeric Materials; Kuryla, W.C., Papa, A.J., Eds.; Marcel
Dekker: New York, 1975, 3, 185.
Weil, E. D. Chapter 4: Synergists, adjuvants and antagonists in flame-retardant systems. In Fire
Retardancy of Polymeric Materials; Grand, A.F., Wilkie, C.A., Eds.; Marcel Dekker:
New York, 2000, 115.
3-12
-------
Weil, E. D. Flame Retardants - Phosphorus Compounds. In Kirk-Othmer Encyclopedia of
Chemical Technology; John Wiley & Sons, Inc.: NY, 1994; 2004 Revision.
Weil, E. D. and Levchik, S. A Review of Current Flame Retardant Systems for Epoxy Resins. J.
Fire Sci. 2004, 22 (Jan).
3-13
-------
4 Hazard Evaluation of Flame Retardants for Printed Circuit
Boards
This chapter summarizes the toxicological and environmental hazards of each flame-retardant
chemical that was identified for potential functional use in printed circuit boards (PCBs)
laminates. Evaluations of chemical formulations may also include associated substances (e.g.,
starting materials, by-products, and impurities) if their presence is specifically required to allow
that alternative to fully function in the assigned role. Otherwise, pure substances were analyzed
in this assessment. Users of the alternative assessments should be aware of the purity of the
trade product they purchase, as the presence of impurities may alter the hazard of the
alternative.
Toxicological and environmental endpoints included in the hazard profiles are discussed in
Section 4.1 along with the criteria used to evaluate each hazard endpoint. Data sources and the
review methodology are described in Section 4.2. The report then offers a detailed description of
the utility of physical-chemical properties in understanding hazard in Section 4.3 and the process
of evaluating human health and environmental endpoints in Section 4.4 and Section 4.5,
respectively. A discussion of the evaluation of endocrine activity is included in Section 4.6. The
characteristics of each chemical included in the alternatives assessment are summarized in the
comparative hazard summary table in Section 4.8. Lastly, the collected data and hazard profile of
each chemical are presented in Section 4.9.
4.1 Toxicological and Environmental Endpoints
The assessment of endpoints with the intent to create hazard profiles for a Design for the
Environment (DfE) alternatives assessment follows the guidance of the DfE Program
Alternatives Assessment Criteria for Hazard Evaluation (U.S. EPA, 2011b). The definitions for
each endpoint evaluated following these criteria are outlined in Section 4.1.1 and the criteria by
which these endpoints are evaluated are outlined in Section 4.1.2. Lastly, there are endpoints
which DfE characterizes but does not assign criteria to and these are summarized in Section
4.1.3.
4.1.1 Definitions of Each Endpoint Evaluated Against Criteria
Hazard designations for each chemical discussed in this report were made by direct comparison
of the experimental or estimated data to the DfE Program Alternatives Assessment Criteria for
Hazard Evaluation (U.S. EPA, 20 lib). Table 4-1 provides brief definitions of human health
toxicity, environmental toxicity and environmental fate endpoints.
Table 4-1. Definitions of Toxicological and Environmental Endpoints for Hazard Assessment
Endpoint
Category
Endpoint
Definition
Human Health
Effects
Acute Mammalian Toxicity
Adverse effects occurring following oral or dermal
administration of a single dose of a substance, or multiple
doses given within 24 hours, or an inhalation exposure of
4 hours.
4-1
-------
Endpoint
Category
Endpoint
Definition
Carcinogenicity
Mutagenicity/Genotoxicity
Reproductive Toxicity
Developmental Toxicity
Neurotoxicity
Capability of a substance to increase the incidence of
malignant neoplasms, reduce their latency, or increase
their severity or multiplicity.
Mutagenicity - The ability of an agent to induce
permanent, transmissible changes in the amount, chemical
properties or structure of the genetic material. These
changes may involve a single gene or gene segment, a
block of genes, parts of chromosomes, or whole
chromosomes. Mutagenicity differs from genotoxicity in
that the change in the former case is transmissible to
subsequent cell generations.
Genotoxicity - The ability of an agent or process to alter
the structure, information content, or segregation of DNA,
including those which cause DNA damage by interfering
with normal replication process, or which in a non-
physiological manner (temporarily) alter its replication.
The occurrence of biologically adverse effects on the
reproductive systems of females or males that may result
from exposure to environmental agents. The toxicity may
be expressed as alterations to the female or male
reproductive organs, the related endocrine system, or
pregnancy outcomes. The manifestation of such toxicity
may include, but is not limited to: adverse effects on onset
of puberty, gamete production and transport, reproductive
cycle normality, sexual behavior, fertility, gestation,
parturition, lactation, developmental toxicity, premature
reproductive senescence or modifications in other
functions that were dependent on the integrity of the
reproductive systems.
Adverse effects in the developing organism that may
result from exposure prior to conception (either parent),
during prenatal development, or postnatally to the time of
sexual maturation. Adverse developmental effects may be
detected at any point in the lifespan of the organism. The
major manifestations of developmental toxicity include:
(1) death of the developing organism, (2) structural
abnormality, (3) altered growth, and (4) functional
deficiency.
An adverse change in the structure or function of the
central and/or peripheral nervous system following
exposure to a chemical, physical or biological agent.
4-2
-------
Endpoint
Category
Environmental
Toxicity
Environmental
Fate
Endpoint
Repeated Dose Toxicity
Respiratory Sensitization
Skin Sensitization
Eye Irritation/Corrosivity
Skin Irritation/Corrosion
Definition
Adverse effects (immediate or delayed) that impair
normal physiological function (reversible and irreversible)
of specific target organs or biological systems following
repeated exposure to a chemical substance by any route
relevant to humans. Adverse effects include biologically
significant changes in body and organ weights, changes
that affect the function or morphology of tissues and
organs (gross and microscopic), mortality, and changes in
biochemistry, urinalysis, and hematology parameters that
are relevant for human health; may also include
immunological and neurological effects.
Hypersensitivity of the airways following inhalation of a
substance.
A cell-mediated or antibody -mediated allergic response
characterized by the presence of inflammation that may
result in cell death, following an initial induction exposure
to the same chemical substance, i.e., skin allergy.
Irritation or corrosion to the eye following the application
of a test substance.
Skin irritation- reversible damage to the skin following the
application of a test substance for up to 4 hours. Skin
corrosion- irreversible damage to the skin namely, visible
necrosis through the epidermis and into the dermis
following the application of a test substance for up to 4
hours.
Environmental toxicity refers to adverse effects observed in living organisms that typically
inhabit the wild; the assessment is focused on effects in three groups of surrogate aquatic
organisms (freshwater fish, invertebrates, and algae).
Aquatic Toxicity (Acute)
Aquatic Toxicity (Chronic)
Environmental Persistence
Bioaccumulation
The property of a substance to be injurious to an organism
in a short-term, aquatic exposure to that substance.
The property of a substance to cause adverse effects to
aquatic organisms during aquatic exposures which were
determined in relation to the life-cycle of the organism.
The length of time the chemical exists in the environment,
expressed as a half-life, before it is destroyed (i.e.,
transformed) by natural or chemical processes. For
alternative assessments, the amount of time for complete
assimilation (ultimate removal) is preferred over the initial
step in the transformation (primary removal).
The process in which a chemical substance is absorbed in
an organism by all routes of exposure as occurs in the
natural environment, e.g., dietary and ambient
environment sources. Bioaccumulation is the net result of
competing processes of chemical uptake into the organism
at the respiratory surface and from the diet and chemical
elimination from the organism including respiratory
exchange, fecal egestion, metabolic biotransformation of
the parent compound and growth dilution.
4-3
-------
The hazard profile for each chemical contains endpoint specific summary statements (see Section
4.9). For each of the endpoints listed in Table 4-1, these summary statements provide the hazard
designation, the type of data (experimental or estimated) and the rationale. The endpoint
summaries may also include explanatory comments, a discussion of confounding factors or an
indication of the confidence in the data to help put the results in perspective.
4.1.2 Criteria
Table 4-2 summarizes the criteria that were used by the U.S. Environmental Protection Agency
(EPA) DfE Program to interpret the data presented in the hazard evaluations. The DfE Program
Alternatives Assessment Criteria for Hazard Evaluation underwent internal and public comment,
and were finalized in 2011 (U.S. EPA, 201 Ib). A hazard designation for each human health
endpoint was not given for each route of exposure but rather was based on the exposure route
with the highest hazard designation. Data may have been available for some or all relevant routes
of exposure.
The details as to how each endpoint was evaluated are described below and in the DfE full
criteria document, DfE Program Alternatives Assessment Criteria for Hazard Evaluation,
available at: http://www.epa.gov/dfe/alternatives assessment criteria for hazard eval.pdf
Table 4-2. Criteria Used to Assign Hazard Designations
Endpoint
Very High
High
Very Low
Human Health Effects
Acute mammalian toxicity
Oral median lethal dose
(LD5o) (mg/kg)
Dermal LD50 (mg/kg)
Inhalation median lethal
concentration (LC50) -
vapor/gas
(mg/L)
Inhalation LC50 - dust/mist/
fume (mg/L)
<50
<200
<2
<0.5
>50-300
>200-1000
>2-10
>0.5-1.0
>300-2000
>1000-2000
>10-20
>l-5
>2000
>2000
>20
>5
—
-
—
—
Carcinogenicity
Carcinogenicity
Known or
presumed
human
carcinogen
(equivalent to
Globally
Harmonized
System of
Classification
and Labeling of
Chemicals
(GHS)
Categories 1A
and IB)
Suspected
human
carcinogen
(equivalent to
GHS Category
2)
Limited or
marginal
evidence of
Carcinogenicity
(And inadequate
evidence in
humans)
Negative studies
or robust
mechanism-
based Structure
Relationship
(SAR)
(As described
above)
4-4
-------
Endpoint
Very High
High
Moderate
Very Low
Mutagenicity/Genotoxicity
Germ cell mutagenicity
Mutagenicity and
genotoxicity in somatic
cells
GHS Category
lAorlB:
Substances
known to
induce heritable
mutations or to
be regarded as
if they induce
heritable
mutations in the
germ cells of
humans
GHS Category
2: Substances
which cause
concern for
humans owing
to the
possibility that
they may
induce heritable
mutations in the
germ cells of
humans
OR
Evidence of
mutagenicity
supported by
positive results
in in vitro AND
in vivo somatic
cells and/or
germ cells of
humans or
animals
Evidence of
mutagenicity
supported by
positive results
in in vitro OR in
vivo somatic
cells of humans
or animals
Negative for
chromosomal
aberrations and
gene mutations,
or no structural
alerts.
-
Reproductive toxicity
Oral (mg/kg/day)
Dermal (mg/kg/day)
Inhalation - vapor, gas
(mg/L/day)
Inhalation - dust/mist/fume
(mg/L/day)
-
-
-
-
<50
<100
<1
<0.1
50-250
100-500
1-2.5
0.1-0.5
>250-1000
>500-2000
>2.5-20
>0.5-5
>1000
>2000
>20
>5
Developmental toxicity
Oral (mg/kg/day)
Dermal (mg/kg/day)
Inhalation - vapor, gas
(mg/L/day)
Inhalation - dust/mist/fume
(mg/L/day)
-
-
-
-
<50
<100
<1
<0.1
50-250
100-500
1-2.5
0.1-0.5
>250-1000
>500-2000
>2.5-20
>0.5-5
>1000
>2000
>20
>5
Neurotoxicity
Oral (mg/kg/day)
Dermal (mg/kg/day)
Inhalation - vapor, gas
(mg/L/day)
Inhalation - dust/mist/fume
(mg/L/day)
-
-
-
-
<10
<20
<0.2
0.02
10-100
20-200
0.2-1.0
0.02-0.2
>100
>200
>1.0
>0.2
-
-
-
-
Repeated-dose toxicity
Oral (mg/kg/day)
-
<10
10-100
>100
-
4-5
-------
Endpoint
Dermal (mg/kg/day)
Inhalation - vapor, gas
(mg/L/day)
Inhalation - dust/mist/fume
(mg/L/day)
Very High
-
-
-
High
<20
O.2
O.02
20-200
0.2-1.0
0.02-0.2
>200
>1.0
>0.2
Very Low
-
-
-
Sensitization
Skin sensitization
Respiratory sensitization
High frequency
of sensitization
in humans
and/or high
potency in
animals (GHS
Category 1A)
Occurrence in
humans or
evidence of
sensitization in
humans based
on animal or
other tests
(equivalent to
GHS Category
1A and IB)
Low to moderate
frequency of
sensitization in
human and/or
low to moderate
potency in
animals (GHS
Category IB)
Limited
evidence
including the
presence of
structural alerts
Adequate data
available and not
GHS Category
lAorlB
Adequate data
available
indicating lack
of respiratory
sensitization
Irritation/corrosivity
Eye irritation/corrosivity
Skin irritation/corrosivity
Irritation
persists for
>21 days or
corrosive
Corrosive
Clearing in 8-
21 days,
severely
irritating
Severe
irritation at
72 hours
Clearing in
<7 days,
moderately
irritating
Moderate
irritation at
72 hours
Clearing in
<24 hours,
mildly irritating
Mild or slight
irritation at
72 hours
Not irritating
Not irritating
Endocrine activity
Endocrine Activity
For this endpoint, High/Moderate/Low etc. characterizations will not apply. A
qualitative assessment of available data will be prepared.
Environmental Toxicity and Fate
Aquatic toxicity
Acute aquatic toxicity -
LC50 or half maximal
effective concentration
(EC50) (mg/L)
Chronic aquatic toxicity -
lowest observed effect
concentration (LOEC) or
chronic value (ChV)
(mg/L)
<1.0
0.1
1-10
0.1-1
>10-100
>1-10
>100orNo
Effects at
Saturation
(NES)
>10orNES
Environmental persistence
4-6
-------
Endpoint
Persistence in water, soil,
or sediment
Persistence in air (half -life
days)
Very High
Half-life
>180 days or
recalcitrant
High
Moderate
Half-life of 60-
180 days
Half-life <60
but>16 days
Low
Half-life
<16 days OR
passes Ready
Biodegradability
test not
including the
10-day window.
No degradation
products of
concern.
Very Low
Passes Ready
Biodegradability
test with 10-day
window. No
degradation
products of
concern.
For this endpoint, High/Moderate/Low etc. characterizations will not apply. A
qualitative assessment of available data will be prepared.
Bioaccumulation
Bioconcentration Factor
(BCF)/Bioaccumulation
Factor (BAF)
Log BCF/BAF
>5000
>3.7
5000-1000
3.7-3
<1000-100
<3-2
<100
<2
"
-
Very High or Very Low designations (if an option for a given endpoint in Table 4-2) were assigned only when there were experimental data
located for the chemical under evaluation. In addition, the experimental data must have been collected from a well conducted study specifically
designed to evaluate the endpoint under review. If the endpoint was estimated using experimental data from a close structural analog, by
professional judgment, or from a computerized model, then the next-level designation was assigned (e.g., use of data from a structural analog
that would yield a designation of Very High would result in a designation of high for the chemical in review). One exception is for the estimated
persistence of polymers with an average molecular weight (MW) > 1,000 daltons, which may result in a Very High designation.
4.1.3 Endpoints Characterized but Not Evaluated
Several additional endpoints were characterized, but not evaluated against hazard criteria. This is
because the endpoints lacked a clear consensus concerning the evaluation criteria (endocrine
activity), data and expert judgment were limited for industrial chemicals (persistence in air,
terrestrial ecotoxicology), or the information was valuable for the interpretation of other toxicity
and fate endpoints (including toxicokinetics and transport in the environment).
Table 4-3. Definitions of Endpoints and Information Characterized but Not Evaluated Against Hazard
Criteria
Toxicological Endpoint
Toxicokinetics
Biomonitoring
Information
Environmental Transport
Persistence in Air
Definition
The determination and quantification of the time course of absorption, distribution,
biotransformation, and excretion of chemicals (sometimes referred to as
pharmacokinetics).
The measured concentration of a chemical in biological tissues where the analysis
samples were obtained from a natural or non-experimental setting.
The potential movement of a chemical, after it is released to the environment, within
and between each of the environmental compartments, air, water, soil, and sediment.
Presented as a qualitative summary in the alternative assessment based on physical-
chemical properties, environmental fate parameters, and simple volatilization models.
Also includes distribution in the environment as estimated from a fugacity model1 .
The half -life for destructive removal of a chemical substance in the atmosphere. The
primary chemical reactions considered for atmospheric persistence include hydrolysis,
direct photolysis, and the gas phase reaction with hydroxyl radicals, ozone, or nitrate
radicals. Results are used as input into the environmental transport models.
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Toxicological Endpoint
Immunotoxicology
Terrestrial Ecotoxicology
Endocrine Activity
Definition
Adverse effects on the normal structure or function of the immune system caused by
chemical substances (e.g., gross and microscopic changes to immune system organs,
suppression of immunological response, autoimmunity, hypersensitivity,
inflammation, and disruption of immunological mechanistic pathways).
Reported experimental values from guideline and nonguideline studies on adverse
effects on the terrestrial environment. Studies on soil, plants, birds, mammals,
invertebrates were also included.
A change in endocrine homeostasis caused by a chemical or other stressor from
human activities (e.g., application of pesticides, the discharge of industrial chemicals
to air, land, or water, or the use of synthetic chemicals in consumer products.)
1A fugacity model predicts partitioning of chemicals among air, soil, sediment, and water under steady state
conditions for a default model "environment" (U.S. EPA, 201 le).
4.2 Data Sources and Assessment Methodology
This section explains how data were collected (Section 4.2.1), prioritized and reviewed (Section
4.2.2) for use in the development of hazard profiles. High-quality experimental studies lead to a
thorough understanding of behavior and effects of the chemical in the environment and in living
organisms. Analog approaches and SAR-based estimation methods are also useful tools and are
discussed throughout this section. Information on how polymers differ from discrete chemicals
in terms of how they are evaluated is presented in Section 4.2.3.
4.2.1 Identifying and Reviewing Measured Data
For each chemical assessed, data were collected in a manner consistent with the High Production
Volume (HPV) Chemical Challenge Program Guidance (U.S. EPA, 1999b) on searching for
existing chemical information. This process resulted in a comprehensive search of the literature
for available experimental data. For chemicals well characterized by experimental studies, this
usually resulted in the collection of recent high-quality reviews or peer-reviewed risk
assessments. These were supplemented by primary searches of scientific literature published
after these secondary sources were released; this is explained in greater detail below. For
chemicals that are not as well characterized, that is, where these secondary sources were not
available or lacked relevant or adequate data, a comprehensive search of the primary scientific
literature was done. Subsequently, these searches led to the collection and review of articles from
the scientific literature, industrial submissions, encyclopedic sources, and government reports. In
addition, data presented in U.S. Environmental Protection Agency (EPA) public databases (e.g.,
integrated risk information system (IRIS); the High Production Volume Information System) and
confidential databases were obtained for this project. Generally, foreign language (non-English)
reports were not used unless they provided information that was not available from other
sources.
Chemical assessments were performed by first searching for experimental data for all endpoints
in Table 4-2. For most alternatives assessed, high-quality secondary sources were not available;
therefore a comprehensive search of the literature was performed to identify experimental data.
In some cases, confidential studies submitted to EPA by chemical manufacturers were also
available to support hazard designations. For those chemicals that were expected to form stable
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metabolites, searches were performed to identify relevant fate and toxicity information for the
metabolite or degradation product.
Well-Studied Chemicals - Literature Search Strategy
As mentioned above, for chemicals that have been well characterized, the literature review
focused primarily on the use of secondary sources, such as Agency for Toxic Substances and
Disease Registry Toxicological Profiles or IRIS assessments. Using high-quality secondary
sources maximized available resources and eliminated potential duplication of effort. However,
more than one secondary source was typically used to verify reported values, which also reduced
the potential for presenting a value that was transcribed incorrectly from the scientific literature.
Although other sources might also contain the same experimental value for an endpoint, effort
was not focused on building a comprehensive list of these references, as it would not have
enhanced the ability to reach a conclusion in the assessment. When data for a selected endpoint
could not be located in a secondary source for an otherwise well-studied chemical, the primary
literature was searched by endpoint and experimental studies were assessed for relevant
information.
Making Predictions in the Absence of Measured Data
In the absence of primary or secondary data, hazard designations were based on (1) Quantitative
Structure Activity Relationship (QSAR)-based estimations from the EPA New Chemical
Program's predictive methods; (2) analog data; (3) class-based assignments from the EPA
Chemical Categories document and (4) expert judgment by EPA subject matter experts.
For chemicals that lacked experimental information, QSAR assessments were made using either
EPA's Estimation Program Interface (EPISuite™) for physical-chemical property and
environmental fate endpoints or EPA's Ecological Structure Activity Relationships
(ECOSAR™) QSARs for ecotoxicity. For the cancer endpoint, estimates were also obtained
from EPA's OncoLogic expert system. These estimation methods have been automated, and are
available for free (U.S. EPA, 2012c). Often analog data were used to support predictions from
models. These approaches were described in the EPA Pollution Prevention (P2) Framework and
Sustainable Futures (SF) program (U.S. EPA, 2005; U.S. EPA, 201 le).
For some physical-chemical properties that could not be estimated using EPISuite™, such as
acid/base dissociation constants, other available methods (e.g., the ACE acidity and basicity
calculator website for dissociation constants) were used (ACE Organic 2013). All estimation
methods employed were limited to those freely available in the public domain.
The methodology and procedures used to assess polymers are described in Section 4.2.3. In
addition, the endpoints for impurities or oligomers with a MW > 1,000 daltons were estimated
using professional judgment and the results assessed for inclusion in the overall hazard
designation. This process is described, as appropriate, under the corresponding endpoints
appearing in Section 4.3.
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When QSAR models were not available, professional judgment was used to identify hazards for
similar chemicals using the guidance from EPA's New Chemicals Categories (U.S. EPA, 2010c).
The categories identify substances that share chemical and toxicological properties and possess
potential health or environmental concerns (U.S. EPA, 2010a). In the absence of an identified
category, analogs for which experimental data are available were identified using EPA's Analog
Identification Methodology (AIM) or by substructure searches of confidential EPA databases
(U.S. EPA, 2012a). If a hazard designation was still not available, the expert judgment of
scientists from EPA's New Chemical Program would provide an assessment of the physical-
chemical properties, environmental fate, aquatic toxicity and human health endpoints to fill
remaining data gaps.
4.2.2 Hierarchy of Data Adequacy
Once the studies were obtained, they were evaluated to establish whether the hazard data were of
sufficient quality to meet the requirements of the assessment process. The adequacy and quality
of the studies identified in the literature review are described in the Data Quality field of the
chemical assessments presented in Section 4.9. The tiered approach described below represents a
general preferred data hierarchy, but the evaluation of toxicological data also requires flexibility
based on expert judgment.
1. One or more studies conducted in a manner consistent with established testing
guidelines
2. Experimentally valid but nonguideline studies (i.e., do not follow established testing
guidelines)
3. Reported data without supporting experimental details
4. Estimated data using SAR methods or professional judgment based on an analog
approach
5. Expert judgment based on mechanistic and structural considerations
In general, data were considered adequate to characterize an endpoint if they were obtained using
the techniques identified in the HPV data adequacy guidelines (U.S. EPA, 1999b). Studies
performed according to Harmonized EPA or Organisation for Economic Cooperation and
Development (OECD) guidelines were reviewed to confirm that the studies followed all required
steps.
Experimental studies published in the open literature were reviewed for their scientific rigor and
were also compared and contrasted to guideline studies to identify potential problems arising
from differences in the experimental design. Data from adequate, well-performed, experimental
studies were used to assign hazard designations in preference to those lacking in sufficient
experimental detail. When multiple adequate studies were available for a given endpoint, any
discrepancies that were identified within the set of data were examined further and addressed
using a weight-of-evidence approach that was described in the data entry to characterize the
endpoint whenever possible.
When available, experimental data from guideline or well-performed experimental studies were
preferred (Items 1 and 2 in the hierarchy list). Information from secondary sources such as
Material Safety Data Sheets, or online databases (such as the National Library of Medicine's
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Hazardous Substances Data Bank, Item 3 in the hierarchy list) was considered appropriate for
some endpoints when it included numerical values for effect levels that could be compared to the
evaluation criteria.
4.2.3 Assessment of Polymers and Oligomers
The methodology and procedures used to assess polymers were slightly different than those used
for oligomers, discrete compounds and simple mixtures. Although experimental data for
polymers were identified using the literature search techniques discussed above in Section 4.2.1,
in the absence of experimental data, estimates were performed using professional judgment as
presented in the literature (U.S. EPA, 201 Ob). The polymers are a mixture of molecules with a
distribution of components (e.g., different chain lengths) that depend on the monomers used,
their molar ratios, the total number of monomeric units in the polymer chain, and the
manufacturing conditions. To account for this variation, the average MW profile (also referred to
as the number average molecular weight MWn) was used in their assessment as the individual
chains rarely have the same degree of polymerization and weight yet their physical, chemical,
and environmental properties are essentially identical for the purposes of this assessment. The
polymers evaluated as alternatives typically have average MWs ranging from > 1,000 to
<100,000 daltons.
For polymers with relatively low average MWs (i.e., those with average MWs generally less than
2,000), the alternative assessment also determined the amount of oligomers and unchanged
monomers (starting materials) in the MW profile with MWs < 1,000 daltons. Special attention
was paid to materials that have a MW <1,000 daltons as these materials often have the highest
hazard (potentially bioavailable substances) in the mixture. This type of assessment was similar
to the evaluation of the hazards of impurities present in discrete chemical products.
Methodological differences between the evaluation of discrete products and polymers are
discussed in Section 4.3.
For the Alternatives Assessment, there were chemicals that are mixtures of low MW oligomers
comprised of 2 or 3 repeating units. The hazard assessment evaluated all oligomers present.
From all the oligomers, the higher concern material was used to assign the hazard designation.
This process is essentially identical to the evaluation of the hazards associated with impurities or
by-products present in discrete chemical products. As a result, the alternatives assessment
process determined the amount of oligomers and unchanged monomers (starting materials)
present and considered their potential hazards in the alternatives designation.
4.3 Importance of Physical and Chemical Properties, Environmental Transport, and
Biodegradation
Physical-chemical properties provide basic information on the characteristics of a chemical
substance and were used throughout the alternatives assessment process. These endpoints
provide information required to assess potential environmental release, exposure, and
partitioning as well as insight into the potential for adverse toxicological effects. The physical-
chemical properties are provided in the individual chemical hazard profiles presented in Section
4.9. For information on how key physical-chemical properties of alternatives can be used to
address the potential for human and environmental exposure, please refer to Table 5-2.
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Descriptions of relevant physical-chemical properties and how they contribute to the hazard
assessments are presented below.
Molecular Weight (MW)
MW informs how a chemical behaves in a physical or biological system including bioavailability
and environmental fate. In general, but not strictly, larger compounds tend to be less mobile in
biological and environmental systems. Their large size restricts their transport through biological
membranes and lowers their vapor pressure. Polymers and oligomers evaluated in this
alternatives assessment were mixtures that contain a distribution of components and they may
not have a unique MW (see also Section 4.2.3). To account for variation in these mixtures, the
average MW or MWn, determined experimentally (typically using high pressure liquid
chromatography, viscosity, or light-scattering), was used in the assessment of polymers. The
assessment of polymers also includes oligomers and unchanged monomers (starting materials)
that have MW of <1,000 daltons as these were often the highest concern materials (bioavailable
substances) in the mixture.
Melting Point and Boiling Point
These two properties provide an indication of the physical state of the material at ambient
temperature. Chemicals with a melting point more than 25°C were assessed as a solid. Those
with a melting point less than 25°C and a boiling point more than 25°C were assessed as a liquid
and those with a boiling point less than 25°C were assessed as a gas. The physical state was used
throughout the assessment, such as in the determination of potential routes of human and
environmental exposure, as described in Chapter 5. The melting and boiling points were also
useful in determining the potential environmental fate, ecotoxicity, and human health hazards of
a chemical. For example, organic compounds with high melting points generally have low water
solubility and low rates of dissolution. These properties influence a material's bioavailability and
were therefore taken into account in both the assessment process and the evaluation of
experimental studies. Similarly, chemicals with a low melting point also have a higher potential
to be absorbed through the skin, gastrointestinal tract, and lungs.
In the absence of experimental data, the melting point value was not reported and no estimations
were performed. If a chemical decomposes before it melts, this information was included in the
assessment. For boiling point, the maximum value reported in the assessment was 300°C for
high boiling materials including polymers (U.S. EPA, 1999b). Melting points for polymers
and/or oligomers were not reported as these materials typically reach a softening point and do
not undergo the phase change associated with melting (i.e., solid to liquid).
Vapor Pressure
Vapor pressure is useful in determining the potential for a chemical substance to volatilize to the
atmosphere from dry surfaces, from storage containers, or during mixing, transfer, or
loading/unloading operations (see Section 5.2). In the assessment process, chemicals with a
vapor pressure less than 1 x 10"6 mm Hg have a low potential for inhalation exposure resulting
from gases or vapors. Vapor pressure is also useful for determining the potential environmental
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fate of a substance. Substances with a vapor pressure more than 1 x 10"4 mm Hg generally exist
in the gas phase in the atmosphere. Substances with a vapor pressure between 1 x 10"4 and 1 x
10"8 mm Hg exist as a gas/particulate mixture. Substances with a vapor pressure less than 1 x 10"8
mm Hg exist as a particulate. The potential atmospheric degradation processes described below
in the reactivity section generally occur when a chemical exists in the gas phase. Gases in the
atmosphere also have the potential to travel long distances from their original point of release.
Materials in the liquid or solid (particulate) phases in the atmosphere generally undergo
deposition onto Earth's surface.
A maximum vapor pressure of 1 x 10"8 mm Hg was assigned for chemicals without experimental
data or for those substances that were anticipated by professional judgment to be nonvolatile
(U.S. EPA, 201 le). The maximum vapor pressure of 1 x 10"8 mm Hg was also the default value
reported for the vapor pressure of and other materials polymers with a MW >1,000 daltons (U.S.
EPA, 201 Ob).
Water Solubility
The water solubility of a chemical provides an indication of its distribution between
environmental media, potential for environmental exposure through release to aquatic
compartments, and potential for human exposure through ingestion of drinking water. Water
solubility was also used extensively to determine potential human health and ecotoxicity hazards.
In general, chemicals with water solubility less than 1 x 10"5 g/L indicate a lower concern for
both the expression of adverse effects, and potential aquatic and general population exposure due
to their low bioavailability. However, chemicals with a low bioavailability also tend to be more
environmentally persistent. Low bioavailability is different than no bioavailability, and the two
should not be used interchangeably.
Within the context of this alternatives assessment, the following descriptors were used according
to ranges of water solubility values: more than 10,000 mg/L was considered very soluble; 1,000-
10,000 mg/L represents soluble; 100-1,000 mg/L represents moderately soluble, 1-100 mg/L
represents slightly soluble, and less than 1 mg/L represents insoluble, noting that these guidelines
might not match what is used elsewhere within the scientific literature for other disciplines.
Chemicals with higher water solubility were more likely to be transported into groundwater with
runoff during storm events, be absorbed through the gastrointestinal tract or lungs, partition to
aquatic compartments, undergo atmospheric removal by rain washout, and possess a greater
potential for human exposure through the ingestion of contaminated drinking water. Chemicals
with lower water solubility are generally more persistent and have a greater potential to
bioconcentrate.
The water solubility of a substance was also used to evaluate the quality of experimental aquatic
toxicity and oral exposure human health studies as well as the reliability of aquatic toxicity
estimates. If the water solubility of a substance was lower than the reported exposure level in
these experiments, then the study was likely to be regarded as inadequate due to potentially
confounding factors arising from the presence of un-dissolved material. For aquatic toxicity
estimates obtained using SARs, when the estimated toxicity was higher than a chemical's water
solubility (i.e., the estimated concentration in water at which adverse effects appear cannot be
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reached because it was above the material's water solubility), the chemical was described as
having NES. An NES designation is equivalent to a low aquatic toxicity hazard designation for
that endpoint.
While assessing the water solubility of a chemical substance, its potential to disperse in an
aqueous solution was also considered. Ideally, a chemicals potential to disperse would be
obtained from the scientific literature. In the absence of experimental data, the potential for
dispersion can be determined from chemical structure and/or comparison to closely related
analogs. There are two general structural characteristics that lead to the formation of dispersions
in water: (1) chemicals that have both a hydrophilic (polar) head and a hydrophobic (nonpolar)
tail (e.g., surfactants), and (2) molecules that have a large number of repeating polar functional
groups (e.g., polyethylene oxide).
The potential for a chemical to disperse influences potential exposure, environmental fate, and
toxicity. Dispersible chemicals have greater potential for human and environmental exposure,
teachability, and aquatic toxicity than what might be anticipated based on the material's water
solubility alone.
Chemicals without experimental data or chemicals that were anticipated by professional
judgment to be sufficiently insoluble and thus were not bioavailable were assigned a water
solubility maximum value of 1 x 10"3 mg/L (U.S. EPA, 201 le). A water solubility of 1 x 10"3
mg/L is the default value used for discrete organics as well as non-ionic polymers with a MW
>1,000 daltons according to information contained in the literature concerning polymer
assessment (U.S. EPA, 2010b). This assignment is consistent with an analysis of the chemicals
used in the development of the water solubility estimation program in EPA's EPISuite™
software. The training set for this model included 1,450 chemicals with a MW range 27-628
daltons and experimental water solubility values ranging from miscible to 4 x 10"7 mg/L
(Meylan, Howard et al., 1996; U.S. EPA, 201 li). Given that water solubility decreases with MW,
a default value of 1 x 10"3 mg/L is consistent with the limited bioavailability expected for
materials with a MW >1,000 daltons.
Octanol/Water Partition Coefficient (Kow)
The octanol/water partition coefficient, commonly expressed as its log value (i.e., log Kow) is
one of the most useful properties for performing a hazard assessment. The log Kow indicates the
partitioning of a chemical between octanol and water, where octanol is used to mimic fat and
other hydrophobic components of biological systems. Chemicals with a log Kow less than 1 are
highly soluble in water (hydrophilic), while those with a log Kow more than 4 are not very
soluble in water (hydrophobic). A log Kow more than 8 indicates that the chemical is not readily
bioavailable and is essentially insoluble in water. In addition, a log Kow greater than
approximately 8 may be difficult to obtain experimentally.
The log Kow can be used as a surrogate for the water solubility in a hazard assessment and is
frequently used to estimate the water solubility if an experimental value is not available. It can
also be used to estimate other properties important to the assessment, including bioconcentration
and soil adsorption, and is a required input for SAR models used to estimate ecotoxicity values.
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For chemicals without data, that are not within the domain of EPISuite™ or that were expected
to be insoluble in water (WS <1 x 10"3 mg/L), a minimum value of 10 was assigned for the log
Kow (U.S. EPA, 201 le). Insoluble chemicals that could be run through EPISuite™ software may
use a log Kow >10 if the result appeared to be valid based on expert review. This assignment is
consistent with an analysis of the chemicals ("training set") used in the development of the
octanol/water partition coefficient estimation program in the EPISuite™ software. The training
set for this model included 10,946 chemicals with a MW range 18-720 daltons and experimental
log Kow values ranging from -3.89 to 8.70 (Meylan and Howard, 1995; U.S. EPA, 201 Ih). Given
that log Kow increases with MW, a default value of 10 is consistent with the limited
bioavailability expected for materials with a MW > 1,000 daltons. A maximum log Kow of-2 was
used for water soluble materials. For most polymers and other materials that are anticipated to be
insoluble in both water and octanol, the log Kow cannot be measured and was therefore not listed.
Flammability (Flash Point)
The flash point of a substance is defined as the minimum temperature at which the substance
emits sufficient vapor to form an ignitable mixture with air. Flash point can be used to identify
hazards associated with the handling of volatile chemicals. Substances with a flash point above
37.8°C (100°F) were commonly referred to as non-flammable, as this is the flammability
definition used in the shipping industry. There are exceptions to this definition such as chemicals
that may form explosive mixtures in the presence of air.
Explosivity
Explosivity refers to the potential for a chemical to form explosive mixtures in air and can be
defined using the limits of flammability. The lower limit of flammability (LFL) is defined as the
minimum concentration of a combustible substance that is capable of propagating a flame
through a homogenous mixture in the presence of an ignition source. The upper limit of
flammability (UFL) is similarly defined as the highest concentration that can propagate a flame.
LFLs and UFLs are commonly reported as the volume percent or volume fraction of the
flammable component in air at 25°C. If the ambient air concentration of the gas (or vapor) is
between the upper and lower explosion limit, then the material has the potential to explode if it
comes in contact with an ignition source. Knowledge regarding the explosivity of a given
material in air is also useful in identifying potential hazards associated with the manufacture and
use of that material.
pH
The pH scale measures how acidic or basic a substance is on a range from 0 to 14. A pH of 7 is
neutral. A pH less than 7 is acidic, and a pH greater than 7 is basic. This scale is used primarily
to identify potential hazards associated with skin or eye contact with a chemical or its aqueous
solutions. The corrosive nature of chemicals that form either strongly basic (high pH) or strongly
acidic (low pH) solutions are generally likely to result in harm to skin and other biological
membranes. For corrosive chemicals, some experimental studies, such as biodegradation tests,
require additional analysis to determine if the tests were performed at concentrations that cause
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harm to microbes in the test (and, therefore, may result in incorrectly identifying a chemical as
persistent in the environment). For chemicals that form moderately basic or acidic solutions in
water, the pH of the resulting solution can be used in lieu of a measured dissociation constant.
Dissociation Constant in Water (pKa)
The dissociation constant determines if a chemical will ionize under environmental conditions.
The dissociation constant in water provides the amount of the dissociated and undissociated
forms of an acid, base, or organic salt in water. Knowledge of the dissociation constant is
required to assess the importance of the other physical-chemical properties used in the hazard
assessment. As the percentage of ionization increases, the water solubility increases while the
vapor pressure, Henry's Law constant, and octanol/water partition coefficient decrease. For acids
and bases, the dissociation constant is expressed as the pKA and pKB, respectively.
Henry's Law Constant
Henry's Law constant is the ratio of a chemical's concentration in the gas phase to that in the
liquid phase (at equilibrium). In environmental assessments, the Henry's Law constant is
typically measured in water at 25°C. The Henry's Law constant provides an indication of a
chemical's volatility from water, which can be used to derive partitioning within environmental
compartments and the amount of material removed by stripping in a sewage treatment plant.
Henry's Law constant values less than 1 x 10"7 atm-m3/mole indicate slow volatilization from
water to air (the Henry's Law constant for the volatilization of water from water is 1 x 10"7 atm-
m3/mole) and values more than 1 x 10"3 atm-m3/mole indicate rapid volatilization from water to
air. To aid in determining the importance of volatilization, the assessment uses two models based
on the Henry's Law constant. These models determine the half-life for volatilization from a
model river and a model lake. A maximum value of 1 x 10"8 atm-m3/mole for the Henry's Law
constant was assigned for chemicals without experimental data or for those that were anticipated
by professional judgment to be nonvolatile.
Sediment/Soil Adsorption/Desorption Coefficient (Koc)
The soil adsorption coefficient provides a measure of a chemical's ability to adsorb to the
organic portion of soil and sediment. This provides an indication of the potential for the chemical
to leach through soil and be introduced into groundwater, which may lead to environmental
exposures to wildlife or humans through the ingestion of drinking water drawn from
underground sources. Chemicals with high soil adsorption coefficients are expected to be
strongly adsorbed to soil and are unlikely to leach into ground water. The soil adsorption
coefficient also describes the potential for a chemical to partition from environmental waters to
suspended solids and sediment. The higher the Koc, the more strongly a chemical is adsorbed to
soil. Strong adsorption may impact other fate processes, such as the rate of biodegradation, by
making the chemical less bioavailable.
The soil adsorption coefficient, Koc, is normalized with respect to the organic carbon content of
the soil to account for geographic differences. The assignments for the degree that a chemical is
adsorbed to soil within the context of the assessment were described qualitatively as very strong
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(above 30,000), strong (above 3,000), moderate (above 300), low (above 30), and negligible
(above 3). When determining the potential for a chemical to adsorb to soil and suspended organic
matter, the potential for a chemical to form chemical bonds with humic acids and attach to soil
also needs to be considered, although this process is generally limited to a small number of
chemical classes.
A maximum value of 30,000 for the Koc was assigned for chemicals without experimental data
or for those that were anticipated by professional judgment to be strongly absorbed to soil (U.S.
EPA, 201 le). A default Koc of 30,000 was used for polymers and other materials with a MW
> 1,000 daltons.
Reactivity
The potential for a substance to undergo irreversible chemical reactions in the environment can
be used in the assessment of persistence. The primary chemical reactions considered in an
environmental fate assessment are: hydrolysis, photolysis, and the gas phase reaction with
hydroxyl radicals, ozone or nitrate radicals. The most important reaction considered in the hazard
assessment of organic compounds is hydrolysis, or the reaction of a chemical substance with
water. Because the rate of hydrolysis reactions can change substantially as a function of pH,
studies performed in the pH range typically found in the environment (pH 5-9) were considered.
The second reaction considered in the assessment is photolysis, the reaction of a chemical with
sunlight. Both hydrolysis and photolysis occur in air, water, and soil, while only hydrolysis was
considered in sediment. The half-lives for reactive processes, if faster than removal via
biodegradation, were used to assign the hazard designation by direct comparison to the DfE
persistence criteria.
For the atmospheric compartment, persistence also includes the evaluation of oxidative gas-
phase processes. These processes include the reaction with ozone, hydroxyl radicals, and nitrate
radicals. Since the average concentration of these oxidative species in the atmosphere has been
measured, the experimental or estimated rate constants were converted to, and reported as, a
half-life in the assessment using standard pseudo first-order kinetics (U.S. EPA, 201 If; U.S.
EPA, 20lid).
For inorganic compounds, an additional chemical process was considered, the potential to be
reduced or oxidized (undergo a redox reaction) under environmental conditions. Redox reactions
change the oxidation state of the species through the transfer of electrons to form another
compound (such as the reduction of Cr(VI) to Cr(III)). A change in the oxidation state of a metal
or inorganic species can result in significant changes in the material's hazard designation. In this
example, going from Cr(VI) to Cr(III) makes the compound less toxic.
Environmental Transport
The persistence of a chemical substance is based on determining the importance of removal
processes that may occur once a chemical enters the environment. As noted in Section 4.3,
chemicals with a half-life of less than 60 days are expected to be at most a Moderate hazard
designation for persistence. Persistence does not directly address the pathways in which a
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chemical substance might enter the environment (e.g., volatilization or disposal in a landfill) and
focuses instead on the removal processes that are expected to occur once it is released into air,
water, soil, or sediment. Similarly, the persistence assessment does not address what might
happen to a chemical substance throughout its life cycle, such as disposal during incineration of
consumer or commercial products. Understanding the environmental transport of a chemical
substance can help identify processes relevant to environmental assessment. For example, if a
chemical is toxic to benthic organisms and partitions primarily to sediment, its potential release
to water should be carefully considered in the selection of alternatives.
Biodegradation
In the absence of rapid hydrolysis or other chemical reactions, biodegradation is typically the
primary environmental degradation process for organic compounds. Determining the importance
of biodegradation is, therefore, an important component of the assessment. Biodegradation
processes are divided into two types. The first is primary biodegradation, in which a chemical
substance is converted to another substance. The second is ultimate biodegradation, in which a
chemical is completely mineralized to small building-block components (e.g., CC>2 and water).
DfE persistence criteria use data that are reported as percent of theoretical ultimate degradation
in the guideline Ready Biodegradability test or as a half-life in other experimental studies; both
of these measurements can be compared directly to the DfE criteria in Section 4.1.2. When
considering primary degradation, the assessment process includes an evaluation of the potential
for the formation of metabolites that were more persistent than the parent materials. Chemical
substances that undergo rapid primary degradation but only slow ultimate biodegradation were
considered to have stable metabolites. In the absence of measured data on the substance of
interest, DfE evaluated the potential for biodegradation for chemicals with a MW <1,000 daltons
using the EPA EPISuite™ models. EPISuite™ estimates the probability for ready biodegradation
as well as the potential for primary and ultimate removal, as described in Section 4.3. A default
Very High persistence hazard designation was assigned for polymers and other materials with a
MW >1,000 daltons according to information contained in the literature concerning polymer
assessment (U.S. EPA, 2010b).
4.4 Evaluating Human Health Endpoints
After data collection and analysis of the physical-chemical properties for the chemicals being
assessed the comparison of the data against the hazard criteria can begin. Section 4.4.1 discusses
how measured data are used to make hazard designations for human health endpoints and
Section 4.4.2 presents the approach for filling in data gaps to make these hazard designations.
4.4.1 Endpoints Characterized and Evaluated Against Criteria Based on Measured Data
This section provides a short description of how measured data were used to designate the level
of hazard for each endpoint. As a reminder, the criteria for the hazard designations are in Table
4-2.
For acute mammalian toxicity the median lethal doses or concentrations were used to assign the
hazard designation. Four levels of hazard designation have been defined ranging from Low to
Very High.
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For cancer the hazard designation was contingent on the level of evidence for increased
incidence of cancer, and not potency. The definitions applied in DfE criteria are based on
International Agency for Research on Cancer levels of evidence (International Agency for
Research on Cancer, 2006). For example, a designation of Very High concern requires that the
substance be characterized as a "known or presumed human carcinogen", whereas a designation
of Low concern requires either negative studies or robust SAR conclusions. A designation of
Moderate was applied as a default value when there was an absence of data suggesting High
carcinogenicity, and an absence of data supporting Low carcinogenicity (i.e., a lack of negative
studies or weak SAR conclusions).
Similarly, the hazard designation for mutagenicity/genotoxicity was also based on the level of
evidence rather than potency. Complete data requirements for this endpoint were both gene
mutation and chromosomal aberration assays. For instances of incomplete or inadequate
mutagenicity/genotoxicity data, a Low hazard designation cannot be given.
For chronic endpoints, such as reproductive, developmental, neurological and repeated dose
toxicity, the hazard designation was based on potency. The evaluation considers both lowest
observed adverse effect levels (LOAELs) and identification of no observed adverse effect levels
(NOAELs) when available. The LOAEL and the NOAEL are experimental dose levels, and their
reliability is dictated by the study design. In studies for which the lowest dose tested resulted in
an adverse effect (and therefore a NOAEL was not established), and in studies for which the
highest dose tested was a NOAEL, a conservative approach using professional judgment was
used to address uncertainty regarding the lowest dose or exposure level that might be expected to
cause a particular adverse effect. For example, in the absence of an established a NOAEL, an
identified LOAEL might fall within the range of a Moderate hazard; however, it is uncertain if a
lower dose, such as one that falls within the range of High hazard exists because no lower doses
were tested. In such cases, professional judgment was applied to assign a hazard designation
when possible. Some degree of uncertainty was evident in results from studies in which a
NOAEL may fall within one hazard range (e.g., Moderate hazard) and the identified LOAEL
falls within a different hazard range (e.g., Low hazard) because the true LOAEL may fall in
either category, but there were not enough experimental data points to determine the true
LOAEL. Professional judgment was also applied to these cases to assign a hazard descriptor
when possible and the rationale used was described in the assessment. Developmental
neurotoxicity was considered and was evaluated using the developmental toxicity criteria, which
are more stringent than the criteria for neurotoxicity, and thus designed to be more protective
(U.S. EPA, 201 Ib).
The criteria for skin and respiratory sensitization, which are immune-based responses, consider
the frequency and potency of the reactions. For skin sensitization, categories were based on the
weight of evidence9 from traditional animal bioassays, but in vitro alternative studies were also
considered. At this time, there are no standard test methods for respiratory sensitization; as a
result there was often no designation for this endpoint.
9 Generally, weight of evidence is defined as the process for characterizing the extent to which the available data
support a hypothesis that an agent causes a particular effect (U.S. EPA, 1999a).
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The evaluation of skin and eye irritation and corrosivity were based on the time to recovery.
4.4.2 SAR - Application of SAR and Expert Judgment to Endpoint Criteria
If measured data pertaining to human health criteria were not available, potential adverse effects
were estimated with SAR analysis. To make these estimates, DfE relied on the expertise of
scientists in EPA's New Chemicals Program who have reviewed thousands of chemicals and
associated data using these methods. SAR uses the molecular structure of a chemical to infer a
physicochemical property that can be related to specific effects on human health. These
correlations may be qualitative ("simple SAR") or quantitative (QSAR). Information on EPA's
use of SAR analysis has been published by U.S. EPA (1994). Public access to free validated
quantitative SAR models for human health endpoints is far more limited than physical-chemical
properties, environmental fate parameters, or ecotoxicology. Carcinogenicity was assessed using
the OncoLogic expert system that provides a qualitative result directly applicable to the DfE
criteria. For other endpoints that required SAR approaches, an analog approach using expert
judgment was used as discussed in Section 4.2. All estimates obtained in this project were
reviewed by EPA scientists having subject matter expertise. Estimates for the other human health
endpoints were based on expert judgment using an analog approach and not through the use of
computerized SAR methodologies.
Carcinogenicity
The potential for a chemical to cause cancer in humans was estimated using OncoLogic expert
system. This program uses a decision tree based on the known Carcinogenicity of chemicals with
similar chemical structures, information on mechanisms of action, short-term predictive tests,
epidemiological studies, and expert judgment.
Polymer Assessment
Estimates for polymers were obtained using information contained in the literature concerning
polymer assessment based on the MW profile (U.S. EPA, 201 Ob). Those polymers with MW
>1,000 were assessed using an appropriate representative structure that has a MW less than or
equal to the average MW. For polymers with an average MW > 1,000 daltons and a significant
amount of low MW material <1,000 daltons, the low MW components were also assessed for
their environmental fate and potential toxicity in order to identify any possible hazards for the
most bioavailable fraction. Similarly, the presence of unreacted monomers requires that the
assessment consider these components for polymers of any MW range. The properties for
polymers with an average MW > 1,000 with no low MW components were generally evaluated as
a single high MW material for each of the properties described below. In general, polymers with
an average MW > 1,000 were not amenable to the available SAR estimation methods and based
on the literature are assumed to have low to no bioavailability. Polymers with MW >1,000 that
were not degradable or reactive are also typically not bioavailable. Polymers with an average
MW >10,000 have potential for adverse effects due to lung overloading when respirable particles
are present (less than ten microns). The potential for fibrosis or cancer are not assumed with high
MW compounds. There may be exceptions to the rules of thumb outlined above and as such this
guidance should not be held as absolute thresholds.
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Polymers and oligomers with MWs < 1,000 were assessed using a representative structure for all
the MW species anticipated to be present in the mixture. The procedures were essentially
identical to those employed for the evaluation of impurities or by-products in discrete chemicals,
although in this case the oligomer with the highest concern was used to drive the hazard
designation. Unreacted monomers, if present, were also assessed and considered in the hazard
evaluation.
4.5 Evaluating Environmental Toxicity and Fate Endpoints
As with endpoints previously mentioned, the preferred method for the evaluation of
environmental endpoints is the use of experimental data. In their absence, the alternatives
assessment uses computerized QSAR models developed by EPA for the evaluation of
environmental endpoints that can be directly compared to the DfE criteria. When measured data
were not available, the aquatic toxicity was estimated using EPA's ECOSAR™ software and the
persistence designation was estimated using models in EPA's EPISuite™ software. The hazard
designation was determined by applying the criteria to these estimates. As a direct result of the
design of these models and their direct application to DfE criteria, the evaluation of
environmental endpoints using experimental or estimated data was discussed together in the
following subsections.
4.5.1 Aquatic Toxicity
For ecological toxicity, the alternatives assessment focused on the hazard designations for acute
and chronic studies on freshwater species of algae, invertebrates, and fish, (often referred to as
the "three surrogate species"). Aquatic toxicity values were reported in the assessment as
follows:
• Acute (estimated or experimental) - LCso in mg/L
• Chronic (experimental) - No observed effect concentration (NOEC) in mg/L
• Chronic (estimated) - ChV, or the geometric mean between the NOEC and the LOEC, in
mg/L
Experimental data reported in the alternatives assessment also included information on the
species tested. Test data on other organisms (e.g., worms) were included in the assessment if data
were readily available. These data would be evaluated using professional judgment to support
hazard designations assigned using the three surrogate species; however, they were not used by
themselves to assign a hazard designation as DfE criteria are not available. Poorly soluble
substances where the water column exposures may not be adequate to describe sediment and
particulate exposures will be identified by a footnote.
If an experimental or estimated effect level exceeded the known water solubility of a chemical
substance, or if the log Kow exceeded the estimated ECOSAR™ cut-off values for acute and
chronic endpoints (which are class specific), NES were predicted for the aquatic toxicity
endpoints. NES indicates that at the highest concentration achievable, the limit of a chemical's
water solubility, no adverse effects were observed (or would be expected). In these cases, a Low
hazard designation was assigned. In the cases where both an estimated water solubility and
ECOSAR™ estimate were used, then an additional factor often was applied to the water
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solubility before a NES designation was assigned to account for the combined uncertainty in the
model estimates.
In the case where an experimental aquatic toxicity value was significantly higher than the
chemical's water solubility, it was likely the result of a poorly conducted study. In this
circumstance, which is generally more frequent for formulated products or mixtures, additional
details were provided in the data quality section to describe why the reported values could not be
used to assign a hazard designation.
EPA's ECOSAR™ estimation program uses chemical structure to estimate toxicity of a chemical
substance using class-specific QSARs. ECOSAR™ automatically determines all of the classes
that a chemical substance may belong to and, therefore, may provide a number of different
ecotoxicity estimates for some or all of the species and durations estimated. Modeled results are
dependent on the functional groups present on the molecule as well as the diversity of chemicals
with experimental data that were used to build the models (their training set). The hazard profiles
report every estimated value returned from ECOSAR™. Narcosis classes (neutral organics) are
only provided for comparative purposes if class-specific QSARs are available; the latter will be
used preferentially. If multiple class-specific QSARs are available, the hazard designation was
based on the most conservative ECOSAR™ estimate, unless expert judgment suggested that an
individual substance was better represented by a specific class based on analysis of the operative
mode of action. However, if the chemical substance is not anticipated to lie within the domain of
the class-specific estimates provided by ECOSAR or to undergo the same mode of action of the
chemicals that appear in their training sets, then the narcosis (baseline toxicity) associated with
the neutral organic class will be used. Experimental log Kow values were used preferentially as
input into ECOSAR™. In their absence, estimated log Kow values from EPISuite™ were used.
ECOSAR™ is maintained and developed as a stand-alone program but is also accessible through
the EPA EPISuite™ program after it is installed; therefore the Estimations Program Interface
(EPI) program was cited for the ECOSAR™ values in this report.
The QSARs for ECOSAR™ were built using experimental data for several chemical classes. For
a chemical class to be defined within ECOSAR™, sufficient acute experimental data were
required to build a QSAR for all three species included in the model. The equations in ECOSAR
are derived from surrogate species offish, zooplankton, and phytoplankton. While these
surrogate species can comprise several genera as well as families, the equations are not intended
to be species specific, but rather estimates of toxicity to the general trophic levels they represent
(fish, aquatic invertebrates, and aquatic plants). There were instances, however, where sufficient
experimental data are not available to build a chronic QSAR for some of the three surrogate
species. When ECOSAR™ did not provide chronic estimates, the acute value (experimental or
estimated) was divided by an acute to chronic ratio (ACR) to arrive at the ChV. ACRs of 10
were used for fish and daphnid and an ACR of 4 was used for algae (Mayo-Bean, Nabholz et al.,
2011).
An estimate of NES is the default value used for organics, oligomers, or non-ionic polymers with
a MW >1,000 daltons in the assignment of aquatic toxicity hazard. In EPA's New Chemical
program, aquatic toxicity is not predicted for chemicals with a MW > 1,000 daltons as uptake has
been found to decrease exponentially with MWs >600 daltons (Nabholz, Clements et al., 1993)
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due to a decrease in passive absorption through respiratory membranes (Mayo-Bean, Nabholz et
al., 2011).
4.5.2 Bioaccumulation
Bioaccumulation is a process in which a chemical substance is absorbed in an organism by all
routes of exposure as occurs in the natural environment, e.g., from dietary and ambient
environment sources. Bioaccumulation is the net result of the competing processes; this includes
uptake, metabolism and elimination of a chemical in an organism. Bioaccumulation can be
evaluated using the BAF, the steady state ratio of a chemical in an organism relative to its
concentration in the ambient environment, where the organism is exposed through ingestion and
direct contact. Experimental BAFs have not been widely available in the scientific literature and,
as a result, experimental BCFs are more commonly used to evaluate the bioaccumulation hazard.
BCFs are defined as the ratio of the concentration of a chemical in an organism to the
concentration of the chemical in the organism's surroundings; BCFs are typically measured for
fish (in water) using guideline studies.
Experimental BAF or BCF values can be compared directly to the DfE criteria for this endpoint
to assign a hazard designation. The BCF/BAF designations range from <100 for a Low
designation to >5,000 for a Very High designation (see 4.1.2). If experimental values were
available for both of these endpoints, and the BCF and BAF were >100 (i.e., above the Low
designation), the largest factor was used to assign hazard designation. If experimental BCFs
<100 were available, the estimated upper trophic BAF from EPISuite™ was used preferentially
if its use resulted in a more conservative hazard designation and if the potential for metabolism
was accurately accounted for within the model estimates.
In the absence of experimental data, evaluation of bioaccumulation potential can be done using
the log Kow and the log octanol/air partition coefficient Koa as estimated by EPISuite™.
However, analysis using Koa requires the use of metabolism data for higher trophic, air breathing
organisms, which can be difficult to obtain from the scientific literature and cannot be readily
estimated. BAFs and BCFs from EPISuite™ were, therefore, typically used for the
bioaccumulation hazard designation when experimental data were lacking. These values can be
compared directly to DfE criteria and the most conservative result was used for the hazard
designation. For chemicals that had estimated bioaccumulation data, available experimental
monitoring data were used to provide insight into the reliability of the model results. For
example, an estimated Low bioaccumulation potential may be increased to a Moderate
designation if a chemical was routinely identified in samples from higher trophic levels, or a
High designation if the chemical was routinely measured in animals at the top of the food chain.
An estimate of Low is the default value used for discrete organics with a MW >1,000 daltons in
the assignment of bioaccumulation hazard. This assignment is consistent with an analysis of the
chemicals used in the development of the bioconcentration and bioaccumulation estimation
programs in the EPISuite™ software (U.S. EPA, 201 Ig). The training sets for these models
included 527 and 421 chemicals, respectively, with a MW range 68-992 daltons (959 daltons for
BAF). Given that BCF and BAF reach a maximum and then decrease with increasing log Kow, a
default value of Low is, in general, consistent with the limited bioavailability expected for
materials with a MW >1,000 daltons. DfE will use all available well-conducted studies when
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evaluating bioaccumulation potential for materials with a MW > 1,000, including environmental
biomonitoring data on higher trophic levels.
In general, for polymers and other materials with a MW > 1,000 daltons, the default
bioaccumulation designation of Low was assigned, arising from their predicted limited
bioavailability (U.S. EPA, 2010b). A more detailed analysis was performed for compounds at or
near this bright line cutoff as well as for polymers with components where residuals <1,000 had
the potential to be present.
4.5.3 Environmental Persistence
A chemical's persistence in the environment is evaluated by determining the type and rate of
potential removal processes. These removal processes were generally divided into two
categories: chemical and biological. Of the chemical degradation processes, an evaluation of
environmental persistence includes the reaction of a chemical with water, also known as
hydrolysis, because water is ubiquitous in the environment. Hydrolysis rate constants can be
obtained from the literature or estimated, and the resulting half-lives can be compared directly to
DfE criteria. For commercial chemicals, hydrolysis tends to be a slower environmental removal
process than biodegradation. Direct and indirect photolysis also represents other potential
chemical degradation processes that are considered in the alternative assessment, and they are
discussed later in this section.
Biodegradation, the most prevalent biological removal process, was divided into two types. The
first is primary biodegradation, in which a chemical substance is converted to another substance
through a single transformation. The second is ultimate biodegradation, in which a chemical is
completely degraded to CC>2, water, and mineral oxides (such as phosphates for chemicals
containing phosphorus). DfE criteria utilize ultimate biodegradation preferentially for the
persistence hazard designation, although primary removal rates were informative in assigning
hazard designations particularly for materials that were transformed slowly, and to a lesser extent
for those that are transformed rapidly.
If ultimate biodegradation data were not available, primary removal data were used in some
cases. For primary removal processes, the potential for the formation of degradation products
that are more persistent than the parent compounds must be considered in the hazard designation.
When present, the persistent degradation products should be evaluated for fate and toxicity. Half-
life data on the persistent degradation products, if available, were used to determine the
assignment for the persistence designation. In the absence of persistent degradation products,
primary biodegradation half-life data were compared directly to the DfE criteria to assign a
hazard designation.
Biodegradation processes can be classified as either aerobic or anaerobic. Aerobic
biodegradation is an oxidative process that occurs in the presence of oxygen. Anaerobic
biodegradation is a reductive process that occurs only in the absence of oxygen. Aerobic
biodegradation is typically assessed for soil and water, while anaerobic biodegradation is
generally assessed in sediment. For determining the persistence hazard, the importance of both
aerobic and anaerobic biodegradation as well as partitioning and transport in the environment
were considered to determine what removal processes were most likely to occur. Anaerobic
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degradation may use any of several electron acceptors depending on their availability in a given
environment and the prevailing redox potential (Eh). The biodegradative populations that are
dominant in a given environment vary with the conditions and so do their biodegradative
capabilities.
One aspect of the assessment is to determine the potential for removal of a chemical substance,
and especially removal attributable to biodegradation within a sewage treatment plant and other
environments. In this assessment, the term "ready biodegradability" refers to a chemical's
potential to undergo ultimate degradation in guideline laboratory studies. A positive result in a
test for ready biodegradability can be considered as indicative of rapid and ultimate degradation
in most environments including biological sewage treatment plants. Ready tests typically include
a 10-day window, beginning when the biodegradation parameter (e.g., disappearance of
dissolved organic carbon from test substance, or theoretical oxygen demand) reaches 10 percent.
The 10-day window must occur within the 28-day length of the test. If the pass level of the test
(60 percent for oxygen demand and CC>2 production; 70 percent for dissolved organic carbon
disappearance) is met in the 10-day window, the chemical received a Very Low hazard
designation. Those that did not pass the 10-day window criterion but met the pass level in 28
days received a Low hazard designation. If ready biodegradability test data were available but
the chemical did not meet the pass level, the chemical was evaluated based on measured data
using the DfE half-life criteria (Table 4-1). These half-life criteria were also used to assign a
hazard designation for nonguideline ultimate biodegradation studies reported in the scientific
literature.
In the absence of a reported half-life, experimental data were also used to approximate half-life
as appropriate. For example, a chemical that undergoes <5 percent removal in 30 days would be
expected to have a half-life >60 days and would be assigned a High persistence concern.
When experimental data on the biodegradation of a chemical substance were not available, the
potential of that substance to undergo this removal process was assessed from the results of the
EPISuite™ models. These models fall into one of four classes: Rapid biodegradation models
based on linear and non-linear regressions that estimate the probability that a chemical substance
will degrade fast; expert survey models that estimated the rate of ultimate and primary
biodegradation using semi-quantitative methods; probability of ready biodegradability in the
OECD 301C test; and probability of rapid biodegradation under methanogenic anaerobic
conditions. Each of these is discussed in the following paragraphs.
The first models (Biowin 5 and 6) used in the screening assessment estimated ready
biodegradability in the OECD 301C test and are also known as Japanese Ministry of
International Trade and Industry (MITI) models. These models provided the probability that a
material passes this standardized test. Those chemicals that were estimated to pass the ready
biodegradability test received a Low persistence designation. If a chemical was not estimated to
pass the MITI test, the results of the other EPISuite™ biodegradation models were used.
The rapid biodegradation potential models within EPISuite™ (Biowin 1 and 2) were useful for
determining if a chemical substance was expected to biodegrade quickly in the environment. If a
chemical was likely to biodegrade quickly, it was generally assigned a Low hazard designation
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for persistence. The results of the estimates from these models may be used in concert with the
semi-quantitative output from a second set of models, which include ultimate and primary
biodegradation survey models (Biowin 3 and 4) for evaluating persistence. These models
provided a numeric result, ranging from 1 to 5, which relates to the amount of time required for
complete ultimate degradation (Biowin 3) and removal of the parent substance by primary
degradation (Biowin 4) of the test compound. The numeric result from Biowin 3 was converted
to an estimated half-life for removal that can be compared directly to DfE criteria. If results from
different models (other than the MITI models) led to a different hazard designation, then the
ultimate biodegradation model results were used preferentially. If the transport properties
indicate the potential for the material to partition to sediment, an anoxic compartment, then the
results of the anaerobic probability model (Biowin 7) will also be evaluated.
Half-lives for hydrolysis from experimental studies or EPISuite™ estimates were used in
preference to biodegradation data when they suggested that hydrolysis is a more rapid removal
process. Hydrolysis half-lives were compared directly to DfE criteria to assign the persistence
designation. Similar to primary biodegradation, breakdown products resulting from hydrolysis
were evaluated for fate and toxicity when they were expected to be more persistent than the
parent compound.
Photolysis may also be an important environmental removal process. In general, environmental
removal rates from photolysis do not compete with biodegradation or hydrolysis although there
are exceptions such as iodides. Photolysis may be an important removal process for chemicals
that were not bioavailable because of their limited water solubility. Estimation methods for
photolysis rates were not available using computerized SAR tools. If experimental or suitable
analog data were available, the rate of photolysis was evaluated relative to other removal
processes.
When evaluating the environmental persistence designation, it should be noted that chemicals
with a High or Very High designation can degrade over time, although this process may occur at
a very slow rate. As a result, a Very High designation may have been assigned if persistent
degradates were expected to be produced, even at a very slow rate, in the absence of
experimental biodegradation data for the parent substance.
Chemicals that contain a metal were assigned a High persistence designation in the assessment,
as these inorganic moieties are recalcitrant. In this instance, an 'R' footnote was added to the
hazard summary table to indicate that the persistence potential was based on the presence of a
recalcitrant inorganic moiety. The assessment process also included the evaluation of the
potential chemical reactions of metal-containing and inorganic moieties to determine if they were
potentially transformed to more or less hazardous forms.
Polymers with a MW >1,000 generally received a Very High persistence designation due to their
lack of bioavailability.
4.6 Endocrine Activity
Chemicals included in DfE alternatives assessments were screened for potential endocrine
activity, consistent with the DfE Program Alternatives Assessment Criteria for Hazard
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Evaluation. Endocrine activity refers to a change in endocrine homeostasis caused by a
chemical or other stressor. An endocrine disrupter is an external agent that interferes in some
way with the role of natural hormones in the body, in a manner causing adverse effects. Relevant
data are summarized in the hazard assessments for each chemical, located in Section 4.9. Data on
endocrine activity were available for two of the alternatives included in this report. For
chemicals without available data on endocrine activity, this was acknowledged with a "no data
located" statement. When endocrine activity data were available, the data are summarized as a
narrative. A unique hazard designation of Low, Moderate or High is not provided for this
endpoint in Table 4-2, for reasons discussed below.
The document Special Report on Environmental Endocrine Disruption: An Effects Assessment
and Analysis describes EPA's activities regarding the evaluation of endocrine disruption (U.S.
EPA, 1997). This report was requested by the Science Policy Council and prepared by EPA's
Risk Assessment Forum. This report states that "Based on the current state of the science, the
Agency does not consider endocrine disruption to be an adverse endpoint per se, but rather to be
a mode or mechanism of action potentially leading to other outcomes, for example, carcinogenic,
reproductive or developmental effects, routinely considered in reaching regulatory decisions"
(U.S. EPA, 1997). The report also states that "Evidence of endocrine disruption alone can
influence priority setting for further testing and the assessment of results of this testing could
lead to regulatory action if adverse effects are shown to occur" (U.S. EPA, 1997).
The 1996 Food Quality Protection Act directed EPA to develop a scientifically validated
screening program to determine whether certain substances may cause hormonal effects in
humans. In response, EPA established the Endocrine Disrupter Screening Program (EDSP) (U.S.
EPA, 2012b). The EDSP is developing requirements for the screening and testing of thousands
of chemicals for their potential to affect the endocrine system. When complete, EPA will use
these screening and testing approaches to set priorities and conduct further testing when
warranted. The science related to measuring and demonstrating endocrine disruption is relatively
new, and validated testing methods at EPA are still being developed.
The EDSP proposes a two-tiered approach that includes initial screening followed by more in-
depth testing when warranted (U.S. EPA, 201 la). The Tier 1 screening battery is intended to
identify chemicals with the potential to interact with the estrogen, androgen, or thyroid hormone
systems through any of several recognized modes of action. Positive findings for Tier 1 tests
identify the potential for an interaction with endocrine systems, but do not fully characterize the
nature of possible effects in whole animals. Tier 2 testing is intended to confirm, characterize,
and quantify the effects for chemicals that interact with estrogen, androgen, and thyroid hormone
systems. These test methods must undergo a four-stage validation process (protocol
development, optimization/prevalidation, validation, and peer-review) prior to regulatory
acceptance and implementation. Validation is ongoing for Tier 1 and Tier 2 methods10. Once
validated test methods have been established for screening and testing of potential endocrine
disrupters, guidance must be developed for interpretation of these test results using an overall
weight-of-evidence characterization.
10 Information on the status of assay development and validation efforts for each assay in EPA's EDSP can be found
at: http://www.epa.gov/oscpmont/oscpendo/pubs/assavvalidation/status.htm.
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To assess the data on endocrine activity, DfE applies the weight-of-evidence approach developed
by the EDSP (U.S. EPA, 201 Ic). This process integrates and evaluates data, and always relies on
professional judgment (U.S. EPA, 201 Ic). To evaluate endocrine activity with this weight-of-
evidence approach, DfE examined multiple lines of evidence (when available) and considered
the nature of the effects within and across studies, including number, type, and
severity/magnitude of effects, conditions under which effects occurred (e.g., dose, route,
duration), consistency, pattern, range, and interrelationships of effects observed within and
among studies, species, strains, and sexes, strengths and limitations of the in vitro and in vivo
information, and biological plausibility of the potential for an interaction with the endocrine,
androgen, or thyroid hormonal pathways.
Most test data for chemicals in this report consist of in vitro assays, but results of in vitro assays
alone were not generally expected to provide a sufficient basis to support a hazard designation
for endocrine disruption. EPA expects that in vivo evidence would typically be given greater
overall influence in the weight-of-evidence evaluation than in vitro findings because of the
inherent limitations of such assays. Although in vitro assays can provide insight into the mode of
action, they have limited ability to account for normal metabolic activation and clearance of the
compound, as well as normal intact physiological conditions (e.g., the ability of an animal to
compensate for endocrine alterations).
As described in the DfE Program Alternatives Assessment Criteria for Hazard Evaluation,
endocrine activity was summarized in a narrative, rather than by High, Moderate or Low hazard
designation. The endocrine activity summaries can be found in the hazard profiles. This is an
appropriate approach because there is no consensus on what constitutes high, moderate or low
concern for this endpoint. The summary of endocrine activity largely relies on representative
studies and expert review summaries.
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Chemical Alternatives and the Toxic Substances Control Act
EPA's DfE program is administered by the Office of Pollution Prevention and Toxics (OPPT), which is charged
with the implementation of the Toxic Substances Control Act (TSCA) and the Pollution Prevention Act (PPA).
Central to the administration of TSCA is the management of the TSCA Inventory. Section 8 (b) of TSCA requires
EPA to compile, keep current, and publish a list of each chemical substance that is manufactured or processed in
the U. S. Companies are required to verify the TSCA status of any substance they wish to manufacture or import
for a TSCA-related purpose. For more information, please refer to the TSCA Chemical Substance Inventory
website: http://www.epa.gov/opptintr/existingchemicals/pubs/tscainventorv/basic.html.
TSCA and DfE Alternatives Assessments
Substances selected for evaluation in a DfE Alternatives Assessment generally fall under the TSCA regulations
and therefore must be listed on the TSCA inventory, or be exempt or excluded from reporting before being
manufactured in or imported to, or otherwise introduced in commerce in, the U.S. For more information see
http://www.epa.gov/oppt/newchems/pubs/whofiles.htm.
To be as inclusive as possible, DfE Alternatives Assessments may consider substances that may not have
been reviewed under TSCA, and therefore may not be listed on the TSCA inventory. DfE has worked with
stakeholders to identify and include chemicals that are of interest and likely to be functional alternatives,
regardless of their TSCA status. Chemical identities are gathered from the scientific literature and from
stakeholders and, for non-confidential substances, appropriate TSCA identities are provided.
Persons are advised that substances, including DfE-identified functional alternatives, may not be introduced into
U.S. commerce unless they are in compliance with TSCA. Introducing such substances without adhering to the
TSCA provisions may be a violation of applicable law. Those who are considering using a substance discussed in
this report should check with the manufacturer or importer about the substance's TSCA status. If you have
questions about reportability of substances under TSCA, please contact the OPPT Industrial Chemistry Branch at
202-564-8740.
4-29
-------
4.7 References
ACE Organic. (2013). "ACE Acidity and Basicity Calculator." Retrieved December 13, 2013,
from http://aceorganic.pearsoncmg.com/epoch-plugin/public/pKa.jsp.
International Agency for Research on Cancer. (2006). "Preamble to the IARC Monographs."
Retrieved April 17, 2012, from
http://monographs.iarc.fr/ENG/Preamble/currentb6evalrationale0706.php.
Mayo-Bean, K., K. V. Nabholz, et al. (2011). Methodology Document for the Ecological
Structure-Activity Relationship Model (ECOSAR) Class Program. Office of Pollution
Prevention and Toxics. Washington, DC.
Meylan, W. M. and P. H. Howard (1995). "Atom/fragment contribution method for estimating
octanol-water partition coefficients." J Pharm Sci 84(1): 83-92.
Meylan, W. M., P. H. Howard, et al. (1996). "Improved method for estimating water solubility
from octanol/water partition coefficient." Environ Toxicol Chem 15(2): 100-106.
Nabholz, J. V., R. G. Clements, et al. (1993). Validation of Structure Activity Relationships
Used by the USEPA's Office of Pollution Prevention and Toxics for the Environmental
Hazard Assessment of Industrial Chemcials. Environmental Toxicology and Risk
Assessment. J. W. Gorsuch, F. J. Dwyer, C. G. Ingersoll and T. W. La Point.
Philadelphia, American Society for Testing and Materials. 2: 571-590.
U.S. EPA. (1994). "Joint Project on the Evaluation of (Quantitative) Structure Activity
Relationships." Retrieved November 18, 2013, from
http://www.epa.gov/oppt/newchems/pubs/ene4147.pdf.
U.S. EPA. (1997). "Special Report on Environmental Endocrine Disruption: An Effects
Assessment and Analysis." Retrieved November 18, 2013, from
http://www.epa. gov/raf/publications/pdfs/ENDOCRINE.PDF.
U.S. EPA. (1999a). "Guidelines for Carcinogen Risk Assessment, Review Draft." Retrieved
November 18, 2013, from
http://www.epa.gov/raf/publications/pdfs/CANCER GLS.PDF.
U.S. EPA. (1999b). "High Production Volume (HPV) Challenge: Determining the Adequacy of
Existing Data." Retrieved November 18, 2013, from
http://www.epa.gov/hpv/pubs/general/datadfm.htm.
U.S. EPA. (2005). "Pollution Prevention (P2) Framework." Retrieved November 18, 2013,
from http ://www.epa.gov/oppt/sf/pubs/p2frame-juneOSa2.pdf.
U.S. EPA. (2010a). "Chemical Categories Report." Retrieved April 17, 2012, from
http://www.epa.gov/opptintr/newchems/pubs/chemcat.htm.
4-30
-------
U.S. EPA. (201 Ob). "Interpretive Assistance Document for Assessment of Polymers. Sustainable
Futures Summary Assessment." Retrieved November 18, 2013, from
http://www.epa.gov/oppt/sf/pubs/iad_polymers_092011 .pdf
U.S. EPA. (2010c). "TSCA New Chemicals Program (NCP) Chemical Categories." Retrieved
November 18, 2013, from
http://www.epa.gov/oppt/newchems/pubs/npcchemicalcategories.pdf.
U.S. EPA. (201 la). "Assay Development." Retrieved April 17, 2012, from
http://www.epa.gov/oscpmont/oscpendo/pubs/assayvalidation/index.htm.
U.S. EPA. (201 Ib). "Design for the Environment Program Alternatives Assessment Criteria for
Hazard Evaluation (version 2.0)." Retrieved November 18, 2013, from
http://www.epa.gov/dfe/alternatives_assessment_criteria_for_hazard_eval.pdf.
U.S. EPA. (201 Ic). "Endocrine Disrupter Screening Program. Weight of the Evidence:
Evaluating Results of EDSP Tier 1 Screening to Identify the Need for Tier 2 Testing."
Retrieved November 18, 2013, from
http://www.regulations.gov/#!documentDetail:D=EPA-HQ-OPPT-2010-0877-0021.
U.S. EPA. (201 Id). "Estimation Program Interface (EPI) Suite." Retrieved April 18, 2012, from
http://www.epa.gov/oppt/exposure/pub s/epi suite, htm.
U.S. EPA. (201 le). "Interpretive Assistance Document for Assessment of Discrete Organic
Chemicals. Sustainable Futures Summary Assessment." Retrieved November 18, 2013,
from http://www.epa.gov/oppt/sf/pubs/iad discretes 092011 .pdf
U.S. EPA. (201 If). "On-line AOPWIN™ User's Guide." Retrieved November 18, 2013, from
http://www.epa.gov/oppt/exposure/pub s/epi suite, htm.
U.S. EPA. (201 Ig). "On-line BCFBAF™ User's Guide." Retrieved November 18, 2013, from
http://www.epa.gov/oppt/exposure/pub s/epi suite, htm.
U.S. EPA. (201 Ih). "On-line KOWWIN™ User's Guide." from
http://www.epa.gov/oppt/exposure/pub s/epi suite, htm.
U.S. EPA. (201 li). "On-line WSKOWWIN™ User's Guide." from
http://www.epa.gov/oppt/exposure/pub s/epi suite, htm.
U.S. EPA. (2012a). "Analog Identification Methodology (AIM)." Retrieved April 17, 2012,
from http ://www.epa.gov/oppt/sf/tools/aim.htm.
U.S. EPA. (2012b). "Endocrine Disrupter Screening Program (EDSP)." Retrieved April 17,
2012, from http://www.epa.gov/scipoly/oscpendo/index.htm.
U.S. EPA. (2012c). "Models & Methods." Retrieved April 17, 2012, from
http ://www. epa. gov/oppt/sf/tool s/methods .htm.
4-31
-------
4.8 Hazard Summary Table
Table 4-4. Screening Level Hazard Summary for Reactive-Flame Retardant Chemicals & Resins
VL = Very Low hazard L = Low hazard = Moderate hazard = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion by-
products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the table.
* TBBPA has been shown to degrade under anaerobic conditions to form bisphenol A (BPA; CASRN 80-05-7). BPA has hazard designations different than TBBPA, as follows:
MODERATE (experimental) for reproductive, skin Sensitization and dermal irritation. § Based on analogy to experimental data for a structurally similar compound. ^The highest hazard
designation of any of the oligomers with MW < 1,000. ¥ Aquatic toxicity: EPA/DfE criteria are based in large part upon water column exposures which may not be adequate for poorly
soluble substances such as many flame retardants that may partition to sediment and particulates.
Chemical
(for full chemical name
and relevant trade
names see the
individual profiles in
Section 4.9)
CASRN
Human Health Effects
Acute Toxicity
Carcinogenicity
Genotoxicity
Reproductive
Developmental
Neurological
Repeated Dose
Skin Sensitization
Respiratory
Sensitization
Eye Irritation
Dermal Irritation
Aquatic
Toxicity
•S*
u
Chronic
Environ-
mental
Fate
o
Bioaccumulation
Exposure Considerations
Availability of flame retardants
throughout the life cycle for reactive and
additive flame-retardant chemicals and
resins
Reactive Flame-Retardant Chemicals
Tetrabromobisphenol A
79-94-7
L
L
L*
L
L
L*
L*
VH
H
H
M
DOPO
35948-25-5
L
M
L
tf
M
M
L
VL
L
M
H
L
Fyrol PMP
63747-58-0
L
L^
L*
AfS
AfS
AfS
AfS
L
L
L
H*
rf
VH
rf
Manufacture
End-of-Life of of FR """^
» Electronics Manufacture
/ (Recycle, Disposal) of FR Resin
Sate and Use ^
of Electronics Manufacture of
k. Manufacture of PCB Laminate
^«-— and Incorporation into ^ "*
Electronics
Reactive Flame-Retardant Resins
D.E.R. 500 Series*
26265-08-7
L
M
M
M
M
M
M
H
M%
M%
L
L
VH
rf
Dow XZ-92547*
Confidential
L
M*
M*
M1
M1
M*
M*
H
M1
VL
L
L
H
VH
rf
Manufacture of
FR *"^M
End-of-Life of ^
jp Electronics Manufacture
f (Recycle, Disposal) of FR Resin
Sate and Use i
of Electronics •
V Manufacture
Manufacture of PCB of Laminate
and Incorporation ^ "^
4-32
-------
Table 4-5. Screening Level Hazard Summary for Additive Flame-Retardant Chemicals
VL = Very Low hazard L = Low hazard = Moderate hazard = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, , H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion by-
products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the table.
R Recalcitrant: Substance is comprised of metallic species (or metalloids) that will not degrade, but may change oxidation state or undergo complexation processes under environmental
conditions. § Based on analogy to experimental data for a structurally similar compound. °Concern linked to direct lung effects associated with the inhalation of poorly soluble particles
less than 10 microns in diameter. A Depending on the grade or purity of amorphous silicon dioxide commercial products, the crystalline form of silicon dioxide may be present. The
hazard designations for crystalline silicon dioxide differ from those of amorphous silicon dioxide, as follows: VERY HIGH (experimental) for carcinogenicity; HIGH (experimental)
genotoxicity; MODERATE (experimental) for acute toxicity and eye irritation. ¥ Aquatic toxicity: EPA/DfE criteria are based in large part upon water column exposures which may not
be adequate for poorly soluble substances such as many flame retardants that may partition to sediment and particulates.
Chemical
(for full chemical name
and relevant trade
names see the
individual profiles in
Section 4.9)
CASRN
Human Health Effects
Acute Toxicity
Carcinogenicity
Genotoxicity
Reproductive
Developmental
Neurological
Repeated Dose
Skin Sensitization
Respiratory
Sensitization
Eye Irritation
Dermal Irritation
Aquatic
Toxicity
3
u
•<
Chronic
Environ-
mental
Fate
Persistence
Bioaccumulation
Exposure Considerations
Availability of flame retardants throughout
the life cycle for reactive and additive
flame-retardant chemicals and resins
Additive Flame-Retardant Chemicals
Aluminum
Diethylphosphinate*
225789-38-8
L
L§
L
L
M^
M§
M§
L
L
VL
M
M
HR
L
Aluminum Hydroxide*
21645-51-2
L
L§
L
L§
L
M§
L
VL
VL
L
L
//*
L
Magnesium
Hydroxide*
1309-42-8
L
L
L
L
L
L
//*
L
Melamine
Polyphosphate1*
15541-60-3
L
M
M
H
M
M
M
L
L
VL
L
L
H
L
Silicon Dioxide
(amorphous)
7631-86-9
A
A
A
L§
Hn
L
LA
VL
L
L
//*
L
Manufacture of Manufacture of
FR ~"N. Resin
End-of-Life of \ /
^^ Electronics \l
^"^ (Recycle, ip
Sale and Disposal) Manufacture of
Use of Laminate
Electronics 1
^v^ Manufacture of PCS ^/
^— and Incorporation 4f
into Electronics
1 Hazard designations are based upon the component of the salt with the highest hazard designation, including the corresponding free acid or base.
4-33
-------
4.9 Hazard Profiles
Tetrabromobisphenol A
VL = Very Low hazard L = Low hazard = Moderate hazard H = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion
by-products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the
table.
» TBBPA has been shown to degrade under anaerobic conditions to form bisphenol A (BPA; CASRN 80-05-7). BPA has hazard designations different than TBBPA, as follows:
MODERATE (experimental) for reproductive, skin sensitization and dermal irritation.
Chemical
CASRN
Human Health Effects
cute Toxicity
<
>>
arcinogenicit
U
enotoxicity
0
eproductive
C£
evelopmental
Q
eurological
Z
%
o
P
•a
%
0)
g"
C£
=
o
kin Sensitizat
C/5
espiratory
msitization
C4 vi
ye Irritation
W
0
ermal Irritat
P
Aquatic
Toxicity
1
u
<
_u
1
JS
U
Environmental
Fate
srsistence
a.
a
o
loaccumulati
CO
Tetrabromobisphenol A
79-94-7
L* VH
H
4-34
-------
Tetrabromobisphenol A
CASRN: 79-94-7
MW: 543.*
MF: C,,H12Br4O2
Physical Forms: Solid
Neat: Solid
Use: Flame retardant
SMILES: Oc(c(cc(cl)C(c(cc(c(O)c2Br)Br)c2)(C)C)Br)clBr
Synonyms: Tetrabromobisphenol A; TBBPA; TBBP-A; 4,4'-Isopropylidenebis(2,6-dibromophenol); 2,2-bis(3,5-dibromo-4-hydroxyphenyl) propane; 3,3',5,5'-
tetrabromobisphenol-A; phenol, 4,4'-isopropylidinebis, (dibromo-); 4,4'-(l-methylethylidene)bis(2,6-dibromophenol); 2,2',6,6'-Tetrabromobisphenol A; 2,2-Bis(3,5-
dibromo-4-hydroxyphenyl)propane; 2,2-Bis(4-hydroxy-3,5-dibromophenyl)propane
Trade names:BA-59P; F-2016; F-2400; F-2400E; FR-1524; Fire Guard FG2000; Firemaster BP 4A; Saytex RB-100; Saytex RB 100PC; Tetrabrom; Tetrabromodian;
Bromdian
Chemical Considerations: This is a discrete organic chemical with a MW below 1,000. EPI v 4.11 was used to estimate physical/chemical and environmental fate
values in the absence of experimental data. Measured values from experimental studies were incorporated into the estimations. TBBPA is produced by bromination of
bisphenol A (BPA). (HSDB, 2013).
Polymeric: No
Oligomeric: Not applicable
Metabolites, Degradates and Transformation Products: TBBPA-glucuronic acid conjugates (mono, di and a mixed glucuronide-sulfate conjugate); TBBPA-sulfate
ester conjugates; tribromobisphenol A and glucuronide of tribromobisphenol A were identified as metabolites in experimental studies.
4-isopropyl-2,6-dibromophenol, 4-isopropylene-2,6-dibromophenol and 4-(2-hydroxyisopropyl)-2,6-dibromophenol were identified as major degradation products by
UV light photolysis; other reported products include di- and tribromobisphenol A, dibromophenol, 2,6-dibromo-4-(bromoisopropylene)phenol, 2,6-dibromo-4-
(dibromoisopropylene)phenol and 2,6-dibromo-l,4-hydroxybenzene. Polybrominated dibenzofurans (PBDF) and dibenzodioxins (PBDD) were identified by pyrolytic
degradation. Debromination of TBBPA to tribrominated-BPA, dibrominated-BPA and BPA has been demonstrated in experimental anaerobic biodegradation studies.
(Eriksson and Jakobsson, 1998; Eriksson et al., 2004; Ravit et al, 2005; EU, 2006; ACC, 2006b; Roper et al., 2007; Environment Canada, 2013; NTP, 2013)
Analog: None Analog Structure: Not applicable
Structural Alerts: Phenols, neurotoxicity (EPA, 2010).
Risk Phrases: 50/53 - Very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment (ESIS, 2012).
Hazard and Risk Assessments: Risk assessments were completed for TBBPA by the European Union in 2006 and Canada in 2013. (EU, 2006; Environment Canada,
2013).
4-35
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
179 (Measured)
181
Reported as a range 181-182°C
(Measured)
178 (Measured)
181 (Measured)
178.35
Reported as 45 1 .5 ± 0.5 K using
differential scanning calorimeter
(Measured)
316
Decomposes (Measured)
>300
(Estimated)
4.7xlO-8at25°C
Reported as 6.24xlO~6 Pa (Measured)
<8.9xl(r8at200C
Organisation for Economic Co-operation
and Development (OECD) Guideline 104
"Vapor Pressure Curve" Spinning rotor
gauge method; reported as < 1.1 9x1 0"5 Pa
(Measured)
3.54x10-"
Reported as 4.72xlO'9 Pa at 298K using
Knudsen effusion method (Measured)
<1
Ashford, 1994; HSDB, 2013
EU, 2006
EU, 2006
WHO, 1995; ACC, 2006b
Kuramochi et al., 2008
Stenger, 1978; WHO, 1995
EPIv4.11;EPA, 1999
BRE, 2009
Lezotte and Nixon, 200 1 (as
cited in EU, 2006; ACC, 2006b)
Kuramochi et al., 2008
WHO, 1995; Hardy and Smith,
Reported in a secondary source.
Study details and test conditions
were not stated.
Reported in a secondary source.
Details and test method were not
stated.
The measurement was performed on
a commercial product which was
not 100% pure.
Adequate study details provided.
Consistent with other reported
values.
TBBPA will decompose before
boiling based on measurements on a
commercial product, which may not
have been 100% pure.
Cutoff value for high boiling
materials according to HPV
assessment guidance.
Valid study with limited details
reported.
Value reported is based on the limit
of quantification of the method. The
vapor pressure was below the limit
of quantification of the method.
Adequate study details provided.
Sufficient study details were not
4-36
-------
Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Water Solubility (mg/L)
Log Kow
DATA
(Measured)
4.16
(Measured)
0.171 ±0.004 at pH 3.05
4. 15 ±0.36 at pH 7.56
30.5 ±1.8 at pH 7.99
228 ±6 at pH 8. 48
1,5 10 ±60 at pH 8.91
27,900 ±400 at pH 9.50 (Measured)
0.72atl5°C
4.16at25°C
1.77 at 35°C (Measured)
0.082
at pH 7.6-8.1 (Measured)
0.148atpH5
1.26atpH7
2.34 at pH 9 (Measured)
4.54
(Measured)
Generator column method used to
evaluate Dow:
pH 3.05 = 6.53 ±0.12
(considered non-ionic form)
pH 7.53 =4.75 ±0.07
REFERENCE
1999
Danish EPA, 1999
Kuramochi et al., 2008
WHO, 1995
Submitted confidential study (as
cited in NOTOX, 2000)
Submitted confidential study (as
cited in MacGregor and Nixon,
2002; EU, 2006)
EU, 2006
Kuramochi et al., 2008
DATA QUALITY
available to assess the quality of this
study.
Limited study details provided.
Reported in a primary source;
demonstrates the relationship
between the pH conditions and the
water solubility of TBBPA as an
ionized and non-ionized compound.
Study details and test conditions
were not available. The original
study was in an unpublished report
submitted to the WHO.
The measured water solubility was
dependent on the flow rates through
the column. The cause of the flow
rate dependency is unknown. The
flow rate dependency is not caused
by a failure to reach equilibrium,
since higher flow rates gave higher
solubility. The samples were
centrifuged to remove dispersed
TBBPA.
Submitted confidential study. The
samples were not assessed for the
presence of colloidal material before
analysis.
Reported in a secondary source.
Reported in a primary source;
demonstrates the relationship
between the pH conditions and the
octanol-water partition coefficient
(log Kow) of TBBPA as an ionized
4-37
-------
Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Flammability (Flash Point)
Explosivity
DATA
pH 8. 12 = 3.00 ±0.03
pH 9. 18 = 1.25 ±0.01
pH 10.19 = -0.293 ±0.020
pH 10.95 = -0.769 ±0.023
pHl 1.83 = -1.22 ±0.00
(Measured)
4.5
(Measured)
<4
(Measured)
6.4
HPLC method (Measured)
3.25
(Measured)
5.903
Reported as 5.90 ± 0.034; method based
on USEPA Product Properties Test
Guideline OPPTS 830.7560. (Measured)
5.3
Reported as a range: 4.5-5.3 (Measured)
Not flammable (Measured)
Dust Explosivity: Maximum Explosion
Pressure (Pmax) = 7.7 bar;
Maximum Rate of Pressure Rise
(dP/dt)max = 379 bar/s;
Kst value = 103 bar.m/s (weak explosion)
(Measured)
REFERENCE
Danish EPA, 1999
EU, 2006
EU, 2006
EU, 2006
MacGregor and Nixon, 200 1 (as
cited in EU, 2006)
WHO, 1995
ICL,2013
Churchwell and Ellis, 2007
DATA QUALITY
and non-ionized compound.
Valid study reported in a secondary
source.
Reported in a secondary source.
Study details and test conditions
were not available.
Reported in a secondary source.
Limited study details available.
Reported in a secondary source.
Reported in secondary source.
Study details and test conditions
were not available.
Reported in safety datasheet and
based on its use as a flame retardant.
Adequate supporting information
provided.
4-38
-------
Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Pyrolysis
pH
pKa
Particle Size
DATA
Under certain high temperature pyrolysis
conditions, TBBPA can form and release
brominated dibenzofurans (PBDF) and
dibenzo-p-dioxins (PBDD). (Measured)
Purified TBBPA was pyrolyzed in open
quartz tubes for 10 minutes resulting
mainly in mono-, di-, tri- and tetra-PBDD
and PBDF.
The formation of PBDD and PBDF
occurred at 0.02, 0.16, and 0.1% for 700,
800, and 900°C. (Measured)
9.4
Method based on OECD Guideline 112.
(Measured)
pKal = 7.5
pKa2 = 8.5 (Measured)
REFERENCE
EU, 2006
WHO, 1995
Lezotte and Nixon, 2002; EU,
2006; ACC, 2006b
WHO, 1995; EU, 2006
DATA QUALITY
Adequate.
Adequate.
^o data located.
Adequate guideline study.
Study details and test conditions
were not available. Reported in a
secondary source.
^o data located.
4-39
-------
Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
HUMAN HEALTH EFFECTS
Toxicokinetics
A laboratory study using human skin indicates TBBPA is not well absorbed dermally. The results
indicated 0.73% of the applied dose penetrated through the skin. Oral administration to rats showed that
TBBPA is rapidly metabolized and eliminated in the feces (>80%). TBBPA and metabolites were detected
in plasma and traces of TBBPA and metabolites were detected in urine (glucuronic acid and sulfate ester
conjugates). The estimated bioavailability following oral dosing is 1.6%. Human volunteers had no
detectable TBBPA in plasma following ingestion of low doses; however, TBBPA metabolites (TBBPA-
glucuronide, TBBPA-sulfate) were detected. TBBPA-glucuronide (25% of the administered dose) was the
only metabolite detected in the urine. TBBPA has been detected in breast milk; although a study in
pregnant rats indicates that there is no significant transfer of TBBPA or its metabolites to the fetus (total
amount of radioactivity in the fetus was approximately 0.34% of the administered dose).
Dermal Absorption in vitro
Human split-thickness skin: Absorbed
dose = 0.73% applied dose (14.06
(ig/cm2); Dermal delivery = 1.60%
applied dose (32.05 (ig/cm2)
Roper, 2005; Roper et al., 2007
Sufficient study details reported in
primary source.
Absorption,
Distribution,
Metabolism &
Excretion
Oral, Dermal or Inhaled
Distribution of TBBPA and its conjugates
was observed in pregnant rats fed 0, 100,
1,000 or 10,000 ppm from gestational day
(GD) 0-16. Free-TBBPA detected in
blood, liver and kidney of dams and
amniotic fluid on GD10 and in the
placenta and amniotic fluid in fetuses on
GDI6. Free-TBBPA was also found in the
stomach of suckling pups from dams in
the high dose group. Conjugated TBBPA
was detected in the liver and kidney and
suckling pups.
Fujitani et al., 2007
Insufficient study details; study is in
Japanese with English abstract.
Male rats exposed to TBBPA via i.v.
injection (20 mg/kg), single oral bolus (2,
20 or 200 mg/kg) or repeated daily oral
doses (20 mg/kg for 5-10 days). TBBPA
is absorbed from the intestinal tract, but is
extracted and metabolized by the liver to
glucuronides that are exported into the
bile.
Solyom et al., 2006
Sufficient study details reported in
primary source.
4-40
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Intravenous injection: half-life in blood
was 82 minutes at a clearance rate of 2.44
mL/min. Major route of elimination was
the bile/feces; 82% eliminated within 36
hours; 0.5% eliminated in the urine.
Single oral bolus: 90-106% eliminated in
feces within 72 hours; 2% in urine.
Repeated dose: 85-98% eliminated in
feces
In an intraperitoneal injection study in
rats, peak concentrations of 14C-TBBPA
were found in all tissues within an hour;
highest concentrations found in fat
followed by the liver, sciatic nerve,
muscles, and adrenals. A small amount of
the administered dose was retained after
72 hours in fatty tissue and muscle (3-6%
and 11-14%, respectively). It has also
been observed that unmetabolized
TBBPA is rapidly excreted in feces (51-
95% of the administered dose) following
single exposure (route not specified).
Birnbaum and Staskal, 2004
Adequate study details reported in a
secondary source.
The half-life of TBBPA was estimated to
be 2 days in Swedish workers engaged in
the recycling process.
Sjodin et al., 2003
Adequate study details reported in a
secondary source.
TBBPA was poorly absorbed in the
gastrointestinal tract in rats following
single oral administration. Approximately
95% of the administered dose was
eliminated in feces and <1% was
eliminated in urine within 72 hours.
Levels in tissues were highest in the liver
and gonads. The maximum half-life in
WHO, 1995
Summary information from an
unpublished study.
4-41
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
any tissue was <3 days.
Placental transfer of hydroxylated BFRs
was observed in rats orally dosed with test
compounds (including TBBPA) on
gestation days (GDs) 10-16. There were
no associated developmental effects at the
dose used in the study (25 mg/kg).
Buitenhuis et al, 2004
Sufficient study details reported in
primary source.
TBBPA has been detected in breast milk,
although a study in pregnant rats indicates
that there is no significant transfer of
TBBPA or its metabolites to the fetus
(total amount of radioactivity in the fetus
was approximately 0.34% of the
administered dose).
EU, 2006
Summary of various studies in a
secondary source.
Only an extremely small percentage of
TBBPA particles are expected to be small
enough (1-2 (im) to be deposited into the
rat lung following inhalation. Particles
that do not reach the alveolar region are
expected to be exhaled. The remainder
will deposit in the respiratory tract, will be
swallowed and absorbed by the
gastrointestinal tract (70% absorbed by
gastrointestinal tract, <4% absorbed
through the lungs).
EU, 2006
General information summarized in
a secondary source.
Recovery of TBBPA (measured as
radioactivity) following single oral
administration to rats:
Feces: 90-95%
Urine: <1%
Tissues: 0.4% (Measured)
Recovery of TBBPA (measured as
radioactivity) following repeated oral
administration to rats (1, 5 or 10 days):
Feces: 82-98%
4-42
ACC, 2006b; Kuester et al.,
2007
Sufficient study details reported in
primary source.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Urine: <0.5%
Tissues: <1%
Unexcreted intestinal contents: 1-10%.
The rats were sacrificed 24 hours after the
last dose. (Measured)
Following oral administration of 14C-
TBBPA to rats, 47% and 51% of the dose
was excreted in the bile within 2 hours,
primarily as 2 metabolites: TBBPA-
glucuronide and TBBPA-diglucuronide.
Estimated systemic bioavailability after
oral dosing: 1.6%
In a single dose study in rats, TBBPA was
rapidly metabolized following oral
administration of 300 mg/kg. Primary
metabolites were TBBPA-glucuronide
and TBBPA-sulfate. Diglucuronide of
TBBPA (a mixed glucuronide-sulfate
conjugate of TBBPA), tribromobisphenol
A, and the glucuronide of
tribromobisphenol A were also present in
low concentrations. A peak plasma
concentration of 103 (imol/L was
achieved within 3 hours with an
elimination half-life of 13 hours. Fecal
excretion of unchanged TBBPA was the
major excretory pathway with (>80%).
Schauer et al, 2006 (as cited in
ACC, 2006b)
Sufficient study details reported in
primary source.
In a single dose study in humans (3 males,
2 females), TBBPA was rapidly
metabolized following oral administration
via gel capsule of 0.1 mg/kg. Primary
metabolites were TBBPA-glucuronide
and TBBPA-sulfate. Only TBBPA-
glucuronide was detected in the urine;
approximately 25% of the administered
Schauer et al., 2006 (as cited in
ACC, 2006b)
Sufficient study details reported in
primary source.
4-43
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Other
DATA
dose was eliminated in urine.
In a single oral dose and bile-cannulated
rat study, TBBPA was readily absorbed,
metabolized and eliminated within 72
hours after dosing of male Sprague-
Dawley rats.
Excretion in oral dosing study: 91.7% in
feces, 0.3% in urine. Residue in tissue was
2% of dose (Primarily large and small
intestines).
Excretion in bile-duct cannulated rat:
26.7% in feces, 71.3% in bile, <1%
residue in tissues. Primary metabolites:
Glucuronic acid and sulfate ester
conjugates. Over 95% of extractable fecal
14C was parent TBBPA.
Rapid clearance of [14C]-labeled TBBPA
from the blood of male F344 or female
Wistar Han rats; single oral or intravenous
administration. Tmax of 14C in blood was
observed at 32 ± 19 minutes in male rats
(200 mg/kg fasted) and 1 14 ± 42 minutes
in females (250 mg/kg nonfasted).
Terminal half-lives were > 5 hours and
systemic bioavailability was < 5%.
No accumulation of TBBPA in tissues of
male Sprague-Dawley rats receiving
1,000 mg/kg for 14 consecutic ve days.
TBBPA was present in breast milk, and
both maternal and fetal serum samples in
two studies, indicating a possible risk of
overexposure of newborns through
breastfeeding.
In bile-cannulated rats, 71% of
administered TBBPA was excreted in the
REFERENCE
Hakk et al., 2000 (as cited in
ACC, 2006b; EU, 2006; NTP,
2013)
Knudsen et al., 2013 Kuester et
al., 2007 (as cited in NTP, 2013)
Kang et al., 2009 (as cited in
NTP, 2013)
Antignac et al., 2008; Cariou et
al., 2008
Birnbaum and Staskal, 2004
DATA QUALITY
Sufficient study details reported in
primary source.
Sufficient study details reported in
NTP technical report.
Sufficient study details reported in
NTP technical report.
Sufficient information in primary
sources.
Sufficient information in review.
4-44
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Acute Mammalian Toxicity
Acute Lethality
Oral
Dermal
DATA
bile. Metabolites found in bile were a
diglucuronide, a monoglucuronide, and a
glucuronide-sulfate ester.
REFERENCE
DATA QUALITY
LOW: Experimental studies indicate TBBPA, administered orally to rats and mice at levels up to 50,000
and 10,000 mg/kg, respectively, and TBBPA administered dermally to rabbits at levels up to 10,000 mg/kg
does not produce substantial mortality. Data from located inhalation studies are not sufficient to consider
for the hazard designation.
Rat oral LD50 >50 mg/kg
(range finding study in rats (2 rats/group)
administered 0.5-50 mg/kg)
Rat oral LD50 >2,000 mg/kg - >50,000
mg/kg
Mouse oral LD50 3,200 mg/kg - > 10,000
mg/kg
Rat oral LD50 >5,000 mg/kg
Mouse oral LD50 >7,000 mg/kg
Mouse oral LD50 > 10,000 mg/kg
Rabbit dermal LD50 >2,000 mg/kg
Guinea pig dermal LD50 >1,000 mg/kg
Rabbit dermal LD50 >2 g/kg (2,000
mg/kg)
Sterner, 1967c
Doyle and Elsea, 1966; WHO,
1995; EU, 2006
Dean et al, 1978b (as cited in
WHO, 1995; EU, 2006)
Mallory et al., 1981b (as cited in
EU, 2006; ECHA, 2013)
ECHA, 2013
ECHA, 2013
WHO, 1995
WHO, 1995
ECHA, 2013
Limited study details reported in an
unpublished study.
Sufficient study details reported.
Limited information in secondary
sources. Sufficient information in
unpublished study.
Sufficient data in unpublished study
conducted in accordance with good
laboratory practices (GLP).
Pre-dates standard guidelines and
GLP; no analytical verification of
test material; unequal amounts of
vehicle administered; no vehicle
control.
Pre-dates standard guidelines and
GLP; no analytical verification of
test material; unequal amounts of
vehicle administered; no vehicle
control.
Limited study details reported in a
secondary source.
Limited study details reported in a
secondary source.
Sufficient information in an
unpublished study conducted in
4-45
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Inhalation
accordance with GLP.
Rabbit dermal LD50 > 10,000 mg/kg
Doyle and Elsea, 1966 (as cited
inEU, 2006; ECHA, 2013)
Sufficient study details reported in
unpublished studies.
Rat, mouse, guinea pigs 8-hour aerosol
inhalation LC50 > 0.5 mg/L (whole-body,
aerosol)
Sterner, 1967b (as cited in EC,
2000; EU, 2006)
Inadequate unpublished study, due
to short observation period (2 days)
and because the particle size of the
aerosol was not measured.
Rat 1 hour inhalation LC50 >57 mg/L
(whole body, vapor)
ECHA, 2013
No GLP data; methodology predates
or was not conducted according to
standardized guidelines; no
analytical verification of test
compound concentrations.
Rat 1-hour inhalation LC50 >1,267 ppm
(whole-body)
Doyle and Elsea, 1966 (as cited
in EU, 2006)
Inadequate, methodological
deficiencies (lack of analysis of the
test atmosphere and stability of the
test compound) raise uncertainties
as to the reliability of this study.
Carcinogenicity
MODERATE: There is evidence of increased incidences of tumors of the uterus in female rats and
interstitial cell adenoma of the testes in male rats orally exposed to TBBPA for up to 105 weeks. There
were also increased incidences of tumors in male mice (hepatoblastoma and combined incidence of
hepatocellular carcinoma or hepatoblastoma of the large intestine and hemangiosarcoma in all organs);
however, there was no evidence of carcinogenicity reported in female mice. In addition, a marginal
concern was estimated based on structure-activity relationships and functional properties. The mechanism
of action of TBBPA carcinogenicity is not clearly understood. While there was some evidence of
carcinogenicity in animals (in male and female rats and male mice, but not in female mice), there is
inadequate evidence of carcinogenicity in humans.
OncoLogic Results
Marginal; likely to have equivocal
carcinogenic activity.
Carcinogenicity (Rat and
Mouse)
2-year oral gavage carcinogenicity study;
B6C3F1/N mice (50/sex/dose) were
administered 0, 250, 500, or 1,000 mg/kg-
day 5 days/week for up to 105 weeks.
Survival was decreased at 1000 mg/kg-
day, and therefore, effects are not reported
4-46
OncoLogic, 2008
NTP, 2011; NTP, 2012; NTP,
2013
Estimated by OncoLogic based on
structure-activity relationships and
functional properties.
Sufficient study details reported.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
for this dose. There was an increase in
incidence of multiple hepatocellular
adenomas in male mice in the 500 mg/kg-
day dose group. Increased incidence of
hepatoblastoma and combined incidence
of hepatocellular carcinoma or
hepatoblastoma were reported in male
mice in the 250 mg/kg-day dose group
when compared to controls. Also, a
significant increased positive trend in the
incidence of adenoma or carcinoma
(combined) was seen in the large intestine
in males. In addition, there was a
significant trend for increased incidence
of hemangiosarcoma in all organs in male
mice.
There was no evidence of carcinogenicity
in female mice.
2-year oral gavage carcinogenicity study;
Wistar Han rats (50 or 60/sex/dose) were
administered 0, 250, 500, or 1,000 mg/kg-
day 5 days/week for up to 105 weeks.
There was a slight increase in incidence of
interstitial cell adenoma of the testis in
male rats (1/50 at 500 mg/kg-day; 3/50 at
1,000 mg/kg-day) as compared to controls
(0/50). There was a significant increase in
the incidences of adenomas and
carcinomas of the uterus in female rats at
500 and 1,000 mg/kg-day compared to
controls. There was also an increased
combined incidence of adenoma,
adenocarcinoma, and malignant mixed
Mullerian tumor of the uterus at these
dose groups (3/50, 7/50, 11/50, 13/50 in
the 0, 250, 500, and 1,000 mg/kg-day
NTP, 2013
Sufficient study details reported.
4-47
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Combined Chronic
Toxicity/Carcinogenicity
Other
Genotoxicity
Gene Mutation in vitro
Gene Mutation in vivo
Chromosomal Aberrations in
vitro
DATA
groups, respectively).
Negative in a tumor promotion study in
male F344 rats exposed in utero and
directly via drinking water for 2 weeks
after weaning.
REFERENCE
CCRIS, 2013
DATA QUALITY
No data located.
Limited study details reported in a
secondary source.
LOW: Experimental studies indicate that TBBPA is not genotoxic to bacterial, mammalian, or yeast cells
in vitro. TBBPA was negative in a micronucleus test in mice in vivo.
Negative, Salmonella typhimurium strains
TA98, TA100, TA1535, or TA1537, orE.
coli strain WP2 zwA/pKMlOl, with or
without metabolic activation.
Negative, several Ames assays in
Salmonella typhimurium strains TA92,
TA98, TA100, TA1535, TA1537 and
TA1538 with and without metabolic
activation. Positive controls responded as
expected.
Negative, several gene mutation assays in
yeast (Saccharomyces cerevisiae D3 and
D4) with and without metabolic
activation. Positive controls responded as
expected.
Negative, induction of intragenic
recombination in two in vitro mammalian
cell assays. No information was provided
regarding positive controls.
Negative, chromosomal aberration in
human lymphocytes. Positive controls
responded as expected.
NTP, 2013
Brusick and Weir, 1976;
Jagannath and Brusick, 1977;
Simon et al., 1979; Curren et al.,
1981; WHO, 1995; EC, 2000;
Darnerud, 2003; EU, 2006
Brusick and Weir, 1976;
Jagannath and Brusick, 1977;
Simon etal., 1979; WHO, 1995
Simonsen et al., 2000; Darnerud,
2003
Gudi and Brown, 2001 (as cited
in EU, 2006)
Sufficient study details reported in
NTP technical report.
Sufficient information in secondary
sources and unpublished reports.
Sufficient information in secondary
sources and unpublished reports.
Limited data in secondary sources.
No data located.
Sufficient information in primary
source.
4-48
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Chromosomal Aberrations in
vivo
No increases in micronucleated
normochromatic erythrocytes in
B6C3F1/N mice administered TBBPA via
oral gavage for 3 months.
NTP, 2013; NTP, 2012
Sufficient study details reported in
NTP technical report.
DNA Damage and Repair
No data located.
Other
No data located.
Reproductive Effects
LOW: Experimental studies indicate TBBPA, administered orally to rats, produces no adverse effects on
reproductive performance or outcomes at levels up to 3,000 mg/kg-day. In some studies there were
changes in testis weights at low doses; the significance of these changes on testicular function is unclear
given the limitations of the studies.
Reproduction/Developmental
Toxicity Screen
In a dietary study, pregnant rats (8/group)
were fed 0, 100, 1,000, or 10,000 ppm
(-17, 149, and 1,472 mg/kg-day) TBBPA
( >98% pure) on GD 10 until day 20 after
delivery. There was no evidence of
maternal toxicity during the study.
Treatment with TBBPA did not affect the
number of implantation sites. No other
reproductive endpoint was assessed.
NOAEL: 10,000 ppm (-1,472 mg/kg-day,
highest dose tested)
LOAEL: Not established
In a dietary study, rats (8-13 males and 6-
10 females/group) were fed 0, 3, 10, 30,
100, 300, 1,000 and 3,000 mg/kg-day
TBBPA (98% pure) for 11 weeks (males)
or 2 weeks during premating and
throughout pregnancy and lactation
(females). Dosing continued in FI
offspring after weaning until necropsy at
approximately 6 weeks of age. Decreased
body weight in dams at highest dose. No
adverse effect on number of litters,
number of implantation sites or number of
Saegusaetal., 2009
Van der Yen etal., 2008
Sufficient study details reported in
primary source, but limited
reproductive data. Doses are TWA
for mean intakes of TBBPA during
GD 10-20, PND 1-9, and post natal
days [PND 10-20) estimated by the
investigators.
Sufficient details provided in the
primary source. Doses were
estimated by the investigators. As
stated in the study, dose-response
analysis of effects based on external
dosing (mg/kg-day) was done using
a nested family of purely descriptive
(exponential) models with the
PROAST software. The method
enables integrated evaluation of the
complete data set. From the best
fitted curve, indicated by
4-49
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
pups per litter.
Increased testicular and pituitary gland
weights in FI males (with BMDL values
of 0.5 and 0.6 mg/kg-day). No other effect
on FI gonads wes seen.
Other reproductive-related effects in
offspring were seen only at high doses
(e.g., decrease in anogenital distance in
females seen at day 7 only but not at day 4
or day 21; number of days until vaginal
opening). BMDLs for these effects are
2736 and 2745 mgkg-day, respectively.
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Reproduction and Fertility
Effects
20-Week, 2-generation reproductive
assay, rats (30/sex/group), administered
TBBPA via oral gavage at 0, 10, 100 or
1,000 mg/kg-day. No effects on
reproductive performance or outcomes.
NOAEL: 1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
ACC, 2002
2-generation drinking water study in mice
administered TBBPA dissolved in water
at a concentration of 200 (ig/L. This
provided a dose of 0.035 mg TBBPA/kg-
day (reagent grade) based on body weight
and daily water consumption (estimated
by the investigators). In the parental
generation, only females were exposed
during gestation; In the FI generation,
4-50
Zatecka et al., 2013
significance at the 5% level, a
critical effect dose (CED) was
alculated most often using a critical
ffect size of 10%; there has been
some criticism of the modeling and
methodology used for this study
along (Banasik et al. 2009).
No data located.
Sufficient details provided in
primary source.
Study is inadequate because only
one dose level was tested. Unknown
toxicological significance of
alterations reported; therefore, study
was not used for hazard
lassification.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Other
pups were exposed to TBBPA during
gestation, lactation, pre-pubertal and
pubertal period, and up to adulthood. No
adverse effect on progeny or sex ratio in
either generation. Significantly reduced
testicular weight, increased prostate and
seminal vesicle weight. No visible
abnormalities or pathological changes in
the morphology of seminiferous tubules.
Significantly increased number of
apoptotic cells in the testes and increased
expression pattern of genes encoding
proteins important during
spermatogenesis (F] generation).
Male rats were administered 0, 10, 100
and 1,000 (ig/kg (0, 0.01, 0.1, 1 mg/kg)
TBBPA via subcutaneous injection on
postnatal day (PND) 1-10. Increased
preputial gland weight; decreased
averages of preleptotene spermatocyte,
pachytene spermatocyte and round
spermatid; decreased cauda epididymal
sperm reserves. These effects were not
statistically different from controls.
Tada et al., 2005
Study in Japanese with English
summary.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Developmental Effects
Reproduction/
Developmental Toxicity
Screen
DATA REFERENCE DATA QUALITY
MODERATE: Based on several studies reporting potentially adverse effects in the range of moderate to
high hazard designations with effects on kidney, liver, thyroid and brain endpoints. Some of the studies
with effects in moderate to high hazard range have limitations in experimental design and/or statistical
methods but cannot be completely dismissed. A number of studies indicate no effects up to relatively high
oral or dietary doses of TBBPA. Based on this weight of evidence, a moderate hazard designation is
assigned.
Evidence of potential for moderate or high developmental toxicity:
Nonstandard experimental studies indicate TBBPA, administered orally, produces adverse hepatic effects
(very slight focal hepatocyte necrosis and enlargement of hepatocytes) at 140.5 mg/kg-day (NOAEL = 15.7
mg/kg-day) in mouse pups and kidney effects (polycystic lesions associated with the dilatation of the
tubules) at 200 mg/kg-day (NOAEL = 40 mg/kg-day) in rats postnatally exposed from PND 4-21. Increased
hearing latencies (most likely related to impairment of the development of the upper (apical) part of the
cochlea) were reported in a dietary 1-generation study at a BMDLio of 8 mg/kg-day. There were also
changes in plasma thyroid hormone levels (decreased TT4 at BMDLio of 30-60 mg/kg-day, and increased
TT3 at BMDLio of 5 mg/kg-day) in rat fetuses. Alterations in pup development were observed following
administration of TBBPA in the diet to pregnant rats at a dose of 10,000 ppm (NOAEL = 1,000 ppm).
These effects included increase in interneurons in the dentate hilus-expressing reelin suggestive of
aberration of neuronal migration. Cholinergic effects were observed in neonatal NMRI mice administered
TBBPA at doses up to 11.5 mg/kg body weight (highest dose tested) on postnatal (PND) 10.
Evidence of low developmental toxicity:
Six oral exposure studies with rats and one with mice using standard exposure scenarios showed no effects
in a range of endpoints including body weight, clinical signs, organ weights, alterations in development of
the fetus, neonatal viability and growth, onset of puberty, estrous cycles, organ histology and brain
morphometry at doses ranging from 1,000 to 10,000 mg/kg-day. Two studies with rats using oral exposure
to relatively low doses (<10 mg/kg-day) of TBBPA showed no changes in thyroid and sperm endpoints.
No data located.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
20-Week, 2-generation developmental
neurotoxicity and neuropathology assay,
rats, administered TBBPA via oral gavage
at 0, 10, 100 or 1,000 mg/kg-day.
Treatment with TBBPA did not induce
significant alterations in FI or F2 pups
regarding body weight, clinical signs,
survival to weaning, or organ weight data.
FO rats exhibited a decrease in T3 at 1000
mg/kg. Decreases in T4 were seen in FO
rats and in Fl offspring at 100 and 1000
mg/kg-day.
NOAEL (developmental): 1,000 mg/kg-
day (highest dose tested)
LOAEL: Not established
ACC, 2002
Sufficient study details provided in
primary source.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Prenatal Development
In a nonstandard assay for gestational and
lactational exposure, mice (6/group) were
fed 0, 0.01, 0.1 or 1.0%TBBPA (99.1%
pure) in the diet from GD 0 to postnatal
day (PND) 27. Approximate daily doses
were 15.7, 140.5 or 1,639.7 mg/kg-day for
gestational period (GDO-17) and 42.1,
379.9 or 4,155.9 mg/kg-day for lactational
period (PNDO-21). No standard
developmental effects. Very slight focal
hepatocyte necrosis and enlargement of
hepatocytes (female pups) were seen at
140.5 / 379.9 mg/kg-day and higher.
NOAEL: 15.7 mg/kg-day during gestation
and 42.1 mg/kg-day during lactation
LOAEL: 140.5 mg/kg-day during
gestation and 379.9 mg/kg-day during
lactation based on very slight focal
hepatocyte necrosis and enlarged
hepatocytes
Tada and Fujitani, 2006
In a dietary study, pregnant rats were fed
0, 100, 1,000, or 10,000 ppm (-17, 149,
and 1,472 mg/kg-day) TBBPA on GD 10
until day 20 after delivery. Treatment with
TBBPA did not result in maternal
toxicity. Maternal exposure to TBBPA did
not affect the number of live offspring,
birth weight, anogenital distance (AGD)
on postnatal day (PND) 1, neonatal
viability and growth, or organ histology
on PND 20, onset of puberty (males and
females), estrous cycle, or organ histology
and brain morphometry on post-natal
week 11.
Saegusaetal., 2009
TWA doses can be estimated for the
combined gestational and lactational
periods as 32, 287, and 2,614
mg/kg-day for the 0.01, 0.1, and 1%
dietary groups, respectively. The
TWA developmental LOAEL would
be 287 mg/kg-day. Study limitations
include statistical deficiencies due to
the failure to control for litter
effects. Littermates were utilized as
independent variables for the
experimental and statistical analysis.
The tendency of littermates to
respond more similarly to one
another than non-litter mates was
not taken into account.
Sufficient details provided in
primary source. Doses are TWA for
mean intakes of TBBPA during GD
10-20, PND 1-9, and PND 10-20)
estimated by the investigators.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
NOAEL (developmental): 10,000 ppm
(-1,472 mg/kg-day, highest dose tested)
LOAEL: Not established
Pregnant rats (25/group) were orally
administered 0, 100, 300 and 1,000 mg/kg
TBBPA by gavage on gestation days
(GDs) 0-19; sacrifices were conducted on
GD 20. There were no lexicologically
significant maternal effects and no
adverse developmental effects.
NOAEL (maternal and developmental):
1,000 mg/kg-day (highest dose tested)
LOAEL: Not established
MPI Research 2001 (as cited in
EU, 2006)
Sufficiently detailed summary of
results in secondary source.
Pregnant rats were orally administered 0,
280, 830 and 2,500 mg/kg-day TBBPA by
gavage throughout gestation. No
lexicologically significant maternal
effects were observed. There were no
significant alterations in the development
of fetuses examined on GD 20 or on pups
monitored up to postnatal day (PND) 21.
NOAEL (maternal and developmental):
2,500 mg/kg-day (highest dose tested)
LOAEL: Not established
Noda et al., 1985 (as cited in
EU, 2006)
Sufficiently detailed summary of
results in secondary source.
Pregnant rats (5/group) were orally
administered 0, 30, 100, 300, 1,000, 3,000
and 10,000 mg/kg TBBPA by gavage on
GDs 6-15. Sacrifices were conducted on
GD 20. Maternal deaths occurred with the
highest dose, but there were no adverse
developmental effects.
NOAEL (maternal): 3,000 mg/kg-day
Goldenthal et al., 1978 (as cited
in EC, 2000; Simonsen et al.,
2000)
Sufficiently detailed summary of
results in primary source.
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DATA
REFERENCE
DATA QUALITY
Postnatal Development
LOAEL (maternal): 10,000 mg/kg-day
based on mortality
NOAEL (developmental): 10,000 mg/kg-
day (highest dose tested)
LOAEL (developmental): Not established
Pregnant rats were orally administered
14C-TBBPA (5 mg/kg) on gestation days
(GDs) 10-16 and were sacrificed on GD
20. No effect on plasma total and free T4
levels in dams and fetuses and on
maternal total and T3 levels. Significant
increase (196%) in TSH levels in fetuses'
plasma (but not in dams). TBBPA did not
seem to bind to transthyretin (TTR) in
vivo.
Darnerud, 2003
Limited scope study. Use of a single
dose level precludes drawing firm
conclusions.
In a nonstandard assay for postnatal
exposure, newborn rats (6/sex/group)
were orally administered 0, 40, 200 and
600 mg/kg-day TBBPA (99.5% pure) by
gavage from day 4-21 after birth and were
sacrificed after the last dose. Kidney
effects (polycystic lesions associated with
dilatation of the tubules) evident at > 200
mg/kg-day.
NOAEL: 40 mg/kg-day
LOAEL: 200 mg/kg-day (based on
polycystic lesions, dilation of tubules in
kidneys)
Fukuda et al., 2004
Sufficient details in primary source.
Male rats were administered 0, 10, 100
and 1,000 (ig/kg (0, 0.01, 0.1, 1 mg/kg)
TBBPA via subcutaneous injection on
postnatal days (PNDs) 1-10. Increased
preputial gland weight; decreased
averages of preleptotene spermatocyte,
Tada et al., 2005
Study in Japanese with English
abstract.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Prenatal and Postnatal
Development
Developmental Neurotoxicity
DATA
pachytene spermatocyte and round
spermatid; decreased cauda epididymal
sperm reserves. These effects were not
statistically different from controls.
NOAEL: 1 mg/kg bw-day (highest dose
tested)
LOAEL: Not established
In 5 -week old rats administered 0, 2,000
or 6,000 mg/kg-day TBBPA for 18 days,
no adverse effects were observed.
NOAEL: 6,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
Pregnant Sprague Dawley rats were
exposed to 0, 100, 1,000 or 10,000 ppm
TBBPA in the diet from GD 10 through
day 20 after delivery (weaning).
Alterations in pup brain development on
postnatal day (PND) 20 (increase in
interneurons in the dentate hilus-
expressing reelin suggestive of aberration
of neuronal migration) in pups from the
high dose group.
NOAEL: 1,000 ppm (-80 mg/kg-day)
LOAEL: 10,000 ppm (-800 mg/kg-day)
based on alterations in pup brain
development
Newborn rats (6/sex/group) were
administered 0, 40, 300, or 600 mg/kg-
day TBBPA (99.5% pure) by gavage on
postnatal days (PNDs) 4 through 21. No
REFERENCE
Fukuda et al., 2004
Saegusa et al., 2012 (as cited in
NTP, 2013)
Fukuda et al., 2004
DATA QUALITY
Sufficient study details reported in a
primary study.
^o data located.
Sufficient study details reported in
NTP technical report. Doses were
reported as ppm in the diet but were
converted to mg/kg/day using EPA
1988 reference values for body
weight and food consumption.
Qualitative observations only.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
significant effects on a variety of reflexes
tested on postnatal day 21.
NOAEL: 600 mg/kg-day (highest dose
tested)
LOAEL: Not established
TBBPA administered to male neonatal
NMRI mice at single oral doses of 0, 0.75,
or 11.5 mg/kg body weight on postnatal
(PND) 10; No neurotoxicity, changes in
spontaneous motor behavior, or clinical
signs of dysfunction; however,
cholinergic effects were observed.
NOAEL: 0.75 mg/kg
LOAEL: 11.5 mg/kg (based on
cholinergic effects)
Viberg and Eriksson, 2011 (as
cited in NTP, 2013)
Sufficient study details reported in
NTP technical report. Study
limitations include statistical
deficiencies due to the failure to
control for litter effects.
Sprague-Dawley rats administered
TBBPA at doses of 0, 100, 1,000 or
10,000 ppm in a soy-free diet from GD 10
- postnatal day (PND) 20. Slight decrease
in serum T3 concentrations in pups on
PND 20; however, no evidence for
developmental brain effects.
NOAEL: 10,000 ppm (-1,472 mg/kg-day;
highest dose tested)
LOAEL: Not established
Saegusaetal., 2009
Sufficient study details reported in
primary source.
In a dietary study, rats (8-13 males and 6-
10 females/group) were fed 0, 3, 10, 30,
100, 300, 1,000, or 3,000 mg/kg-day
TBBPA (98% pure) for 11 weeks (males)
or 2 weeks during premating and
throughout pregnancy and lactation for
females (doses estimated by the
investigators). After weaning, dosing of
van der Yen etal., 2008;
Lilienthal et al. (2008)
As stated in the study, dose-
response analysis of effects based
on external dosing (mg/kg-day) was
done using a nested family of purely
descriptive (exponential) models
with the PROAST software. The
method enables integrated
evaluation of the complete data set.
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DATA
REFERENCE
DATA QUALITY
I continued for life. Neurobehavioral
testing was conducted between postnatal
days (PNDs) 50 and 140.
Increase in hearing latencies were seen,
with a BMDL10 calculated to be 8 mg/kg-
day. Other changes in auditory responses
using other types of measures resulted in
higher BMDL values.
Changes in plasma thyroid hormone
levels were seen, with decreased T4 at
BMDL10 of 30.8 mg/kg-day (males) and
16.1 mg/kg-day (females). Increased T3
levels were seen in female offspring, with
a BMDLio of 2.3 mg/kg-day.
Increases in pituitary gland and testis
weights were seen in male F1 offpring
(with BMDLs of 0.6 and 0.5 mg/kg-
bw/day, respectively). Other offspring
effcts (e.g., changes in body weight) were
seen at much higher doses and not
necessarily seen throughout the study.
20-Week, 2-generation developmental
neurotoxicity and neuropathology assay,
rats, administered TBBPA via oral gavage
at 0, 10, 100 or 1,000 mg/kg-day. No
significant neurobehavioral or
neuropathological alterations in F2 pups
identified at various times up to postnatal
day 60.
NOAEL: 1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
ACC, 2002
From the best fitted curve, indicated
by significance at the 5% level, a
critical effect dose (CED, also
referred as Benchmark Dose) was
calculated most often using a critical
effect size of 10%; there has been
some criticism of the modeling and
methodology used for this study
along with noted study limitations
not consistent with recommended
study guidelines (Banasik et al.
2009; Strain et al. 2009; comparison
with OPPTS 870.6855).
Sufficient study details in primary
source.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Other
No data located.
Neurotoxicity
LOW: An experimental study in rats produced no adverse neurotoxic effects in adults at levels up to 1,000
mg/kg-day. In an acute exposure study, TBBPA, administered orally to mice, resulted in neurobehavioral
effects; these effects were not clearly dose-dependent. Although one study with limitations appears to
result in neurobehavioral effects, a well-designed subchronic duration study did not identify any adverse
neurological effects. Based on study quality, a Low hazard designation was assigned.
Neurotoxicity Screening
Battery (Adult)
In a 90-day study, rats (10-15/sex/dose)
were administered daily doses of 0, 100,
300 or 1,000 mg/kg-day TBBPA via in
corn oil. A detailed functional
observational battery (FOB) was
conducted pre-test and at week 12. Motor
activity (MA) was also assessed at week
12. No neurobehavioral effect of
treatment with TBBPA was evident.
NOAEL: 1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
Male mice (14-15/group) were
administered 0, 0.1, 5, or 250 mg/kg-day
TBBPA (99% pure) by gavage 3 hours
before a series of neurobehavioral tests
(open field test, Y-maze test or training of
contextual fear conditioning paradigm).
No gross abnormalities. No significant
differences in the number of rearing and
grooming behaviors. Increased horizontal
movement activities (5 mg/kg-day),
increased freezing behavior in fear
conditioning paradigm (0.1 or 5 mg/kg-
day), increase in spontaneous alternation
behavior in Y-maze test at the low dose,
but no adverse effects occurred at higher
doses. Elevated levels of TBBPA were
detected in the striatum region of the brain
4-60
Nakajimaetal., 2009
MPI Research, 2002 (as cited in
EU, 2006)
Sufficient study details in secondary
source.
Sufficient details in primary source.
Difficult to establish a
NOAEL/LOAEL due to lack of
dose-response relationships; acute
study duration is not a standard
methodology for a neurotoxicity
screening study.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Other
DATA
at lower doses (0.1 or 5 mg/kg-day). At
the highest dose tested (250 mg/kg-day),
there was non-specific accumulation of
TBBPA in the brain.
Potential for neurotoxic effects based on a
structural alert for phenols
(Estimated)
REFERENCE
Professional judgment
DATA QUALITY
Estimated based on a structural alert
and professional judgment.
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DATA
REFERENCE
DATA QUALITY
Repeated Dose Effects
LOW: Based on a weight of evidence indicating that effects occur at doses >100 mg/kg-day. Mice
administered 500 mg/kg-day TBBPA for 3 months were reported to have increased liver weight and
kidney effects in males (NOAEL=100 mg/kg-day). There was decreased serum alanine aminotransferase
and sorbitol dehydrogenase activity at week 14 in male and female rats at 100 mg/kg-day following oral
exposure for 3 months. Increased liver weights and decreased spleen weight were reported in male rats in
the 500 and 1,000 mg/kg-day dose group, though no treatment-related histopathologic lesions were
observed. Experimental studies indicate that TBBPA, administered orally to mice, produced effects on the
liver (inflammatory cell infiltration) at > 350 mg/kg-day (lowest dose tested). In a dietary study in mice,
changes in hematology and clinical chemistry (decreased red blood cells, hemoglobin, hematocrit, serum
triglycerides and total serum proteins) and decreased body weight gain occurred at 2,200 mg/kg-day
(NOAEL: 700 mg/kg-day) while mortality was reported at the highest dose tested (7,100 mg/kg-day). In a
2-year oral gavage carcinogenicity study in mice, renal tubule cytoplasmic alteration and effects on the
forestomach (ulcer, mononuclear cell cellular infiltration, inflammation, and epithelium hyperplasia) were
observed at > 250 mg/kg-day (lowest dose tested). Mean body weight was reduced by at least 10% in this
study at 1,000 mg/kg-day. In a 2-year oral gavage carcinogenicity study in rats, mean body weight was
reduced by at least 10% following exposure to > 500 mg/kg-day and at 1,000 mg/kg-day. Thymus weight
was reduced and liver weight was also increased in this study. Clinical signs of toxicity (excessive salivation
and nasal discharge) were evident in rats following inhalation exposure at levels of 6 mg/L (NOAEC: 2
mg/L). Very slight dermal erythema was present in rabbits following application of 100 mg/kg-day
TBBPA; however, this occurred in the absence of any systemic effects (NOAEL: 2,500 mg/kg-day).
4-62
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Tetrabromobisphenol A CASRN 79-94-7
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DATA
REFERENCE
DATA QUALITY
3 month oral gavage study in F344/Ntac
rats (10/sex/dose); rats were administered
0, 10, 50, 100, 500, or 1,000 mg/kg-day, 5
days/week for 14 weeks.
Dose-related decrease in total thyroxine
concentrations were reported on day 4 at
the final week of the study at 500 and
1,000 mg/kg-day, but not consistently in
the 100 mg/kg-day dose group in males
and female rats. There was a small
decrease in hematocrit levels, hemoglobin
concentrations, and erythrocyte counts in
female rats in the 500 and 1,000 mg/kg-
day dose groups by week 14. There was
also decreased serum alanine
aminotransferase and sorbitol
dehydrogenase activity at week 14 in
males and females of the 100 mg/kg-day.
Increased liver weights and decreased
spleen weight were reported in male rats
in the 500 and 1,000 mg/kg-day dose
group. Although enzyme changes are seen
at lower doses, it is uncertain if this is
linked to any of the observed adverse
endpoints. No treatment-related
histopathologic lesions were observed.
NOAEL: 100 mg/kg-day
LOAEL: 500 mg/kg-day (based on
decreased serum enzyme activity)
NTP, 2013
Sufficient study details reported in
NTP technical report
3 month oral gavage study in B6C3F1/N
mice (10/sex/dose); Mice were
administered 0, 10, 50, 100, 500, or 1,000
mg/kg-day, 5 days/week for 14 weeks.
There was no mortality reported. Final
mean body weight of treated mice in all
NTP, 2013
Sufficient study details reported in
NTP technical report.
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DATA
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DATA QUALITY
dose groups was similar to controls. Liver
weights were significantly greater in male
mice in the 500 and 1,000 mg/kg-day dose
groups as compared to controls. Increased
spleen weights and decreased kidney
weights were reported in the male 1,000
mg/kg-day dose group. Increased
incidence of renal tubule cytoplasmic
alteration in the kidney at 500 and 1,000
mg/kg in male mice (greater severity at
1,000 mg/kg).
NOAEL: 100 mg/kg-day
LOAEL: 500 mg/kg-day (based on
alterations in the kidneys in male mice)
In a 2 8-day dietary study, rats
(25/sex/group) were fed a diet containing
TBBPA at 0, 1, 10, 100 and 1,000 ppm (~
0.07, 0.7, 7.2 and 75 mg/kg-day in males,
and 0.07, 0.77, 7.4 and 72 mg/kg-day in
females). No changes in general
appearance, behavior, body weight or
food consumption. No compound-related
mortality, gross or microscopic lesions in
the liver, kidneys, and thyroid.
NOAEL: 1,000 ppm (75 or 72 mg/kg-day
in males and females, respectively;
highest dose tested)
LOAEL: Not established
Sterner, 1967c (as cited in
Wazeter et al., 1972); Simonsen
et al., 2000; ACC, 2006b; EU,
2006; ECHA, 2013
Study limited by histological
examination of only the liver,
kidneys, and thyroid.
28-day repeated-dose study, rat, diet, no
treatment-related effects.
NOAEL: ~ 98 mg/kg-day (0.1%, highest
dose tested)
LOAEL: Not established
Wazeter et al., 1972
Inadequate, the high dose was
relatively low and failed to elicit
toxicity.
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Tetrabromobisphenol A CASRN 79-94-7
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DATA
REFERENCE
DATA QUALITY
In a 90-day repeated-dose study, rats were
fed 0.3, 3, 30 or 100 mg/kg-day TBBPA
in the diet. No lexicologically significant
effects.
NOAEL: ~ 100 mg/kg-day (highest dose
tested)
LOAEL: Not established
Quastetal., 1975
Sufficient details in a primary
source. However, it was tested at
relatively low doses.
In a 14-day oral study, male mice (7-
8/group) were dosed by gavage with 0,
350, 700 or 1,400 mg/kg-day TBBPA
(99.1% pure) in olive oil. No clinical
signs or mortality. Significant increase in
absolute and relative liver weight in high-
dose mice. Slight enlargement of
hepatocytes at > 700 mg/kg-day,
inflammatory cell infiltration at > 350
mg/kg-day, and focal necrosis of
hepatocytes at 1,400 mg/kg-day. In
treated mice the liver appeared swollen
and the pancreas looked slightly enlarged
and edematous.
NOAEL: Not established
LOAEL: 350 mg/kg-day (lowest dose
tested)
Tada et al., 2007
Sufficient details in primary source.
In a 14-day oral study, male rats (6/group)
were administered 0, 200, 500 or 1,000
mg/kg TBBPA (98% pure) by gavage in
corn oil. No significant adverse effects on
body weight, clinical chemistry
parameters, or enzymes' activities
indicative of lipid peroxidation in the
kidneys.
NOAEL: 1,000 mg/kg-day (highest dose
Kang et al., 2009
Study of limited toxicological
scope. There was no histological
examination of the kidneys.
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DATA
REFERENCE
DATA QUALITY
tested)
LOAEL: Not established
B6C3F1 mice (10/sex/group) were fed
TBBPA in the diet at 0, 71, 700, 2,200 or
7,100 mg/kg-day for 3 months. All
animals receiving 7,100 mg/kg-day died,
but no deaths occurred at lower doses.
Decreased body weight gain at the two
highest doses with no change in food
consumption. Decreased red blood cells,
hemoglobin, hematocrit, serum
triglycerides and total serum proteins at
2,200 mg/kg-day. Increased spleen weight
with blood observed outside the red pulp.
No other organ weight or pathological
changes.
NOAEL: 700 mg/kg-day
LOAEL: 2,200 mg/kg-day
IPCS, 1995; WHO, 1995;
HSDB, 2013; NTP, 2013
Sufficient study details reported in a
secondary source.
In a 90-day repeated-dose study, rats were
administered TBBPA via oral gavage at 0,
100, 300 or 1,000 mg/kg-day. No deaths.
No effect on clinical signs, body/organ
weight, histopathology, urinalysis,
ophthalmology, or serum chemistries.
NOAEL: 1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
MPI Research, 2002 (as cited in
EU, 2006)
Sufficient details in a secondary
source.
10-day developmental study, rats orally
gavaged with 0, 30, 100, 300, 1,000,
3,000 and 10,000 mg/kg TBBPA-day.
Maternal clinical signs, mortality and
reduced body weight gain at the high dose
only (10,000 mg/kg-day). No effects at
3,000 mg/kg-day or less.
Goldenthal et al., 1978
Sufficient details in primary source.
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DATA
REFERENCE
DATA QUALITY
NOAEL: 3,000 mg/kg-day
LOAEL: 10,000 mg/kg-day
In an oral study, 5-week old rats were
administered 0, 2,000 or 6,000 mg/kg-day
TBBPA (99.5% pure) by gavage for 18
days. There were no changes in general
behavior, body weight or kidney weight.
Microscopic examination of the kidneys
showed no abnormalities.
NOAEL: 6,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
Fukuda et al., 2004
Limited scope study; only the
kidneys were examined.
In a 2 8-day dietary study, rats
(10/sex/group) were fed 0, 30, 100 and
300 mg/kg-day TBBPA (98% pure).
Decreased circulating T4 and increased
T3 levels in males (BMDLs = 48 and 124,
respectively). No histopathological
changes in the thyroid or pituitary gland.
Van der Yen etal., 2008
As stated in the study, dose-
response analysis of effects based
on external dosing (mg/kg-day) was
done using a nested family of purely
descriptive (exponential) models
with the PROAST software. The
method enables integrated
evaluation of the complete data set.
From the best fitted curve, indicated
by significance at the 5% level, a
critical effect dose (CED, also
referred as Benchmark Dose) was
calculated at a default critical effect
size of 10%.
2-year oral gavage carcinogenicity study;
Wistar Han rats (50 or 60/sex/dose) were
administered 0, 250, 500, or 1,000 mg/kg-
day 5 days/week for up to 105 weeks.
Survival was similar to controls.
Decreased mean body weight (by at least
10% compared to controls) after week 25
in males in the 500 and 1,000 mg/kg dose
NTP, 2013
Sufficient study details reported in
NTP technical report.
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
groups. At the 3-month interim sacrifice,
there were no treatment-related lesions in
either sex. However, thymus weight was
decreased and liver weight was increased
at 1,000 mg/kg.
NOAEL: 250 mg/kg
LOAEL: 500 mg/kg (based on decreased
mean body weight in males)
2-year oral gavage carcinogenicity study;
B6C3F1/N mice (50/sex/dose) were
administered 0, 250, 500, or 1,000 mg/kg-
day 5 days/week for up to 105 weeks.
Reduced survival in males and females in
the 1,000 mg/kg dose group. Decreased
mean body weight (by at least 10%
compared to controls) after week 25 in
females at 1,000 mg/kg. Increase in the
incidence of renal tubule cytoplasmic
alteration in 250 and 500 mg/kg males.
Significant increase in the incidences of
ulcer, mononuclear cell cellular
infiltration, inflammation, and epithelium
hyperplasia in the forestomach in males at
500 mg/kg and in females at 250 and 500
mg/kg.
NOAEL: Not established
LOAEL: 250 mg/kg (based on effects in
the forestomach in females)
NTP, 2013
Sufficient study details reported in
NTP technical report.
21-day repeated-dose study in rabbits with
dermal application of 0, 100, 500 and
2,500 mg/kg TBBPA to the intact or
abraded back 6 hours/day, 5 days/week.
Very slight erythema (> 100 mg/kg-day).
No compound-related changes in body
Sterner, 1967c (as cited in
Goldenthal et al., 1979;
Simonsen et al., 2000; EU,
2006; ECHA, 2013)
Sufficient details in secondary
source.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Skin Sensitization
Skin Sensitization
DATA
weights, hematologic and biochemical
parameters and urinalysis. No compound
induced gross or microscopic lesions in
any of the tissues examined. No
compound-related organ weight variations
occurred.
NOAEL: 2,500 mg/kg-day (highest dose
tested)
LOAEL: Not established
In a 14 -day inhalation study, rats
(4/sex/group) were exposed whole-body
to 0, 2, 6 or 18 mg/L TBBPA as dust 4
hours/day, 5 days/week. No significant
effects on body weight gain, food
consumption, hematology and clinical
chemistry parameters or urinalysis. No
deaths and no gross or microscopic
lesions. Excessive salivation at 2 mg/L;
excessive salivation, nasal discharge and
lacrimation at > 6 mg/L.
NOAEC: 2 mg/L
LOAEC: 6 mg/L
REFERENCE
Sterner, 1967c (as cited in
Wazeter et al., 1975; Simonsen
et al., 2000; EC, 2000; ECHA,
2013)
DATA QUALITY
No information regarding how the
exposure atmosphere was generated
or regarding analytical
measurements of exposure
concentrations.
LOW: TBBPA is not a skin sensitizer in humans or guinea pigs.
Non-sensitizing, human volunteers
In a modified Draize Multiple Insult test.
Non-sensitizing, guinea pigs
No irritation was elicited at either
induction or challenge in the group
exposed to TBBPA.
Not sensitizing, guinea pigs
Three treated animals showed a mild skin
reaction at the induction site, no treated
Sterner, 1967c; Dean et al.,
1978a; WHO, 1995; EC, 2000;
EU, 2006; ECHA, 2013
Mallory et al., 1981c (as cited in
EU, 2006)
Dean et al., 1978c (as cited in
EU, 2006)
Sufficient study details in secondary
sources.
Sufficient study details in a primary
source.
Sufficient study details in a primary
source.
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Respiratory Sensitization
Respiratory Sensitization
*.«-.
Eye Irritation
Dermal Irritation
Dermal Irritation
DATA
animal showed a skin reaction at the
challenge site.
REFERENCE
DATA QUALITY
No data located
|No data located.
MODERATE: Slight pain, conjunctivitis and corneal damage lasting for three days were reported in
rabbits administered TBBPA in a 10% solution. In addition, moderate conjunctival erythema, clearing
within 72 hours, was also reported following application of TBBPA to the eyes of rabbits.
Application of the test material to the eye
of rabbits produced no irritation in one
rabbit, mild conjunctival erythema in
eight rabbits, and moderate conjunctival
erythema in the remaining three rabbits.
Effects diminished in intensity or
subsided completely during subsequent 72
hours.
Irritating, range-finding study in rabbits.
Undiluted test material caused very slight
immediate conjunctivitis (disappearing
within 48 hours). TBBPA administered as
10% solution in water caused slight pain,
conjunctivitis and corneal damage (lasting
for 3 days and then returning to normal
within a week).
Non-irritating, rabbits
Doyle and Elsea, 1966 (as cited
in EU, 2006)
EU, 2006
Sterner, 1967a (as cited in
Mallory et al., 198 la; WHO,
1995; EU, 2006)
Sufficient details in primary source.
Sufficient details in secondary
source.
Sufficient study details in secondary
sources.
LOW: Slightly irritating to rabbits in a 21-day dermal repeated dose study.
Irritating, rabbits
21 -day repeated dermal toxicity assay
with very slight dermal erythema
persisting for 1-3 days.
Non-irritating, rabbits
Undiluted test material was applied to
intact and abraded skin.
Sterner, 1967c; Goldenthal et al.,
1979; EU, 2006
Doyle and Elsea, 1966; Sterner,
1967c; Mallory etal., 198 Id;
EC, 2000; EU, 2006
Sufficient details in primary
sources.
Sufficient details in primary
sources.
4-70
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Non-irritating, human volunteers
In a modified Draize Multiple Insult test.
Sterner, 1967c; Dean et al.,
1978a; EC, 2000; EU, 2006
Sufficient details in primary source.
Endocrine Activity
Both whole animal and in vitro studies indicate that TBBPA may exhibit thyroid endocrine activity. In a
one-generation reproduction study in rats, TBBPA decreased circulating thyroxine (T4) and increased
circulating T3 levels in males. TBBPA was negative for agonistic and antagonistic estrogenic responses
following oral exposure and subcutaneous injection at doses up to 1,000 mg/kg-day in an uterotrophic
assay with adult female ovariectomized mice. TBBPA has a high potency in competing with thyroxine (T4)
for binding to transport protein transthyretin (TTR) in in vitro animal studies. In addition, TBBPA
exhibited significant thyroid hormonal activity towards rat pituitary cell line GH3, which releases growth
hormone in a thyroid hormone-dependent manner. TBBPA produced only mild effects during long-term
treatment on larval development using the amphibian Xenopus laevis; however, short-term exposure
revealed indirect evidence that TBBPA can function as a TH antagonist. There were no adverse effects on
tail resorption in tadpoles that were microinjected with TBBPA during development. TBBPA did not
induce Vitellogenin in immature rainbow trout after intraperitoneal injection.
TBBPA did not exhibit thyroid hormonal
activity in a thyroid hormone-responsive
reporter assay using a Chinese hamster
ovary cell line (CHO-K1) transfected with
thyroid hormone receptor alpha 1 or betal.
TBBPA showed significant anti-thyroid
hormone effects on the activity of T3 in
the concentration range of 3x10"6 to 5x10~5
M. In addition, TBBPA (in the
concentration range of IxlO"8 to IxlO"6 M
showed suppressive action on T3
enhancement of tadpole tail shortening.
One-generation reproduction study in
Wistar rats fed TBBPA at doses of 0, 3,
10, 30, 100, 300, 1,000 and 3,000 mg/kg-
day. Decreased circulating thyroxine (T4)
and increased circulating T3 levels in
males.
BMDL: 31 (male) and 16 (female) mg/kg-
day
Kitamura et al., 2005a
Van der Yen etal., 2008
Sufficient study details reported in a
primary source.
Sufficient study details summarized
in a primary source.
4-71
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
There were no adverse effects on tail
resorption in tadpoles microinjected with
TBBPA at doses up to 60 (ig at
developmental stage 58 (hind limbs
emerged; forelimbs formed, but not
emerged).
HSDB, 2013
Sufficient study details summarized
in a secondary source.
TBBPA inhibited the binding of
triiodothyronine (T3; IxlO"10 M) to
thyroid hormone receptor in the
concentration range of IxlO"6 M to IxlO"4
M. The thyroid hormonal activity of
TBBPA was also examined using rat
pituitary cell line GH3 cells. TBBPA
enhanced the proliferation of GH3 cells
and stimulated their production of growth
hormone (GH) in the concentration range
of IxlO'6 M to IxlO'4 M. TBBPA did not
show antagonistic action (did not inhibit
the hormonal activity of T3 to induce
growth and GH production of GH3 cells).
TBBPA enhanced the proliferation of
MtT/E-2 cells (growth is estrogen-
dependent).
Kitamura et al., 2002
Sufficient study details in a primary
source.
TBBPA gave a positive response in an in
vivo uterotrophic assay using
ovariectomized mice but was inactive for
effects on the androgenic activity of
Salpha-dihydrotestosterone in mouse
fibroblast cell line NIH3T3. TBBPA
exhibited significant thyroid hormonal
activity towards rat pituitary cell line
GH3, which releases growth hormone in a
thyroid hormone-dependent manner.
Kitamura et al., 2005b
Sufficient study details in a primary
source.
In a uterotrophic assay with adult female
ovariectomized mice, TBBPA was
administered by oral gavage and
Ohtaetal., 2012 cited in
Environment Canada, 2013
Sufficient study details in a
secondary source.
4-72
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
subcutaneous injection daily for 7 days.
TBBPA was negative for agonistic and
antagonistic estrogenic responses by both
routes of exposure at concentrations up to
1,000 mg/kg-day.
Positive for thyroid hormone agonist
activity in a yeast two-hybrid assay
incorporating human thyroid hormone
with and without metabolic activation.
Metabolic activation by rat liver S9
significantly increased the
agonist/antagonist potential.
HSDB, 2013
Sufficient study details summarized
in a secondary source.
Negative for estrogenic activity in yeast
two-hybrid assay. REC10(M) >lxlO"5
compared to 3xlO"10 for E2.
Nishiharaetal., 2000
Sufficient study details reported in a
primary source.
In vitro competition binding assays of T4
to TTR using human plasma samples; the
competing potency of TBBPA was 5
times greater than T4.
Bergman et al., 1997
Sufficient study details reported in a
primary source.
The human adrenocortical carcinoma cell
line (H295R cell line) was used to assess
possible effects of TBBPA on the activity
of adreno cortical enzyme CYP17. A
maximum of 2-fold induction of CYP17
activity occurred after 24 hours of
incubation. TBBPA was a potent inducer
of CYP17 activity, causing 50% induction
at the lowest concentration tested
(O.OljiM).
Canton et al., 2004
Sufficient study details reported in a
primary source.
In a 14-day oral study, male mice (7-
8/group) were dosed by gavage with 0,
350, 700 or 1,400 mg/kg-day TBBPA
(99.1% pure) in olive oil. No clinical
signs or mortality. In treated mice the
liver appeared swollen and the pancreas
Tada et al., 2007
Sufficient details in primary source.
4-73
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
looked slightly enlarged and edematous.
NOAEL: Not established
LOAEL: 350 mg/kg-day (lowest dose
tested)
Negative, thyroid hormone receptor (TR)-
binding activity of TBBPA using a yeast
two-hybrid assay; REC10(M) >3.0xlO'4
compared to 2. IxlO"8 for T3.
Kitagawa et al., 2003
Sufficient study details reported in a
primary source.
Hormonal effects of TBBPA were
investigated in vitro on recombinant
yeasts and in vivo on mosquitofish
(Gambusia affinis). TBBPA had a weak
androgenic activity with recombinant
yeast systems carrying human androgen
receptor (hAR). Following 60-days of
exposure in mosquitofish, significant up-
regulation of vitellogenin (Vtg), and
estrogen receptor (ER-alpha and ER-beta)
mRNAs was observed in the liver (500
nM of TBBPA). The lowest concentration
(50 nM) markedly induced Vtg, ER-beta
and AR-beta mRNA expression in the
testes and significantly inhibited AR-
alpha expression. TBBPA did not produce
histopathological alterations in the liver or
testis.
Huang etal., 2013
Sufficient study details reported in a
primary source.
TBBPA did not have anti-androgenic
activity in a recombinant cell-based in
vitro bioassay using the Chinese hamster
ovarian cell line (CHO Kl).
Roy et al., 2004
Sufficient study details reported in a
primary source.
In a transcriptional activation assay,
TBBPA suppressed the thyroid
replacement element (TRE) mediated
transcriptional activity of T3 on the
human HeLaTRDR4-luc cell line.
4-74
Sakai et al., 2003
Sufficient study details reported in a
primary source.
-------
Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
ER-, DR-CALUX® and T4-TTR
competitive binding assays; TBBPA did
not show estrogenic/antiestrogenic or
dioxin-like/anti-dioxin activity. TBBPA
was more potent than to thyroxine (T4) in
binding to transport protein transthyretin
(TTR).
Legler et al, 2002
Sufficient study details reported in a
primary source.
Vitellogenin induction in immature
rainbow trout after intraperitoneal
injection of TBBPA was studied.
Exposure to TBBPA did not induce
vitellogenin synthesis.
Christiansen et al., 2000
Sufficient study details reported in a
primary source.
The estrogen-dependent human breast
cancer cell line MCF-7 was used to
characterize estrogen-like profiles of high
volume chemicals.
The EC50 for the displacement of
radiolabeled 17 (3-estradiol from the
estrogen receptor = 2.5 (+/- 1.29) x 10"5;
Relative binding affinity (RBA) = 0.013.
Olsen et al., 2003
Sufficient study details reported in a
primary source.
Tadpoles were exposed to TBBPA at
concentrations ranging from 2.5 to 500
(ig/L for 21 days. Larval development was
inhibited only at the highest concentration
level. The TH receptor beta-mRNA was
not affected. Conversely, short-term
exposures to TBBPA slightly increased
the expression of TH receptor beta- and
basic region leucin zipper transcription
factor b/Zip-mRNA but inhibited their
T3-induced elevation in a dose-dependent
manner indicating that TBBPA can
function as a TH antagonist.
Jagnytsch et al., 2006
Sufficient study details reported in a
primary source.
Short (24 h) exposures of TBBPA
modulated the expression of a number of
TH target genes implicated in neural stem
4-75
Finietal., 2012
Sufficient study details reported in a
primary source.
-------
Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
cell function and neural differentiation.
TBBPA also reduced cell proliferation in
the brain ofXenopus laevis (African
clawed frog).
Thyroid hormone (TH) disrupting activity
of TBBPA was investigated in the rat
pituitary cell line GH3. The effect of a
strong antiestrogen, ICI (10~9 M), was also
analyzed on E2 and TBBPA.
TBBPA stimulated GH3 cell growth but
could not counteract the inhibiting growth
effect of 10"9 M ICI at the tested
concentrations. These data indicate that
the effect of TBBPA is TH-like and ER-
mediated.
Ghisari and Bonefeld-Jorgensen,
2005
Sufficient study details reported in a
primary source.
In vitro bioassay with phenobarbital-
induced rat liver microsomes. TBBPA and
TBBPA-DBPE significantly increased
TTR-binding potencies and E2SULT-
inhibiting potencies after
biotransformation. TBBPA-DBPE
became a more potent AR-antagonist after
biotransformation. TBBPA and TBBPA-
DBPE enhanced GH3 cell proliferation in
the T-Screen test.
Hamers et al., 2008
Sufficient study details reported in a
primary source.
TBBPA binded to crystal structures of the
hormone-metabolizing enzyme, estrogen
sulfotransferase (SULT1E1), and has the
potential to cause endocrine disruption.
Gosavi et al., 2013
Sufficient study details reported in a
primary source.
4-76
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Immunotoxicity
The data located had limited experimental details. TBBPA inhibits expression of CD25, which is essential
for proliferation of activated T lymphocyte cells, at concentrations > 3 uM. In a disease challenge study,
TBBPA administered to mice (1% in diet for 28 days; approximately 1,800 mg/kg-day) produced irregular
changes in cytokine production and immune cell populations, which were suggested to cause exacerbation
of pneumonia in respiratory syncytial virus-infected mice. Determination of significance of the response to
RSV infection is limited by the study design having only one, particularly high, dose of TBBPA. In an in
vitro study, TBBPA decreased the level of cell surface proteins, possibly interfering with NK cell function.
Immune System Effects
TBBPA is immunotoxic in culture;
inhibits expression of CD25 at
concentrations at > 3 (JVI; CD25 is
essential for proliferation of activated T
cells and is commonly used as a marker
for T-cell activation.
In a 90-day oral study in mice, there were
no adverse effects at doses up to 700
mg/kg-day; however, 2,200 mg/kg-day
produced increased spleen weight and
reduced concentrations of red blood cells,
serum proteins and serum triglycerides.
NOAEL: 700 mg/kg-bw
LOAEL: 2,200 mg/kg-bw
In vitro study in natural killer (NK) cells;
TBBPA (5 (iM) decreased the level of cell
surface proteins, possibly interfering with
NK cell function.
TBBPA administered to mice as 1% in
diet for 28 days. Irregular changes in
cytokine production and immune cell
populations were suggested to cause
exacerbation of pneumonia in respiratory
syncytial virus-infected mice.
Birnbaum and Staskal, 2004
Tobeetal., 1986; WHO, 1995;
Simonsen et al., 2000; Darnerud,
2003
Hurd and Whalen, 2011 (as cited
inNTP, 2013)
Watanabe et al., 2010 (as cited
inNTP, 2013)
Limited information in a secondary
source.
Limited details in secondary
sources.
Sufficient study details reported in
NTP technical report.
Sufficient study details reported in
NTP technical report.
4-77
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
ECOTOXICITY
ECOSAR Class
Acute Aquatic Toxicity
Fish LC50
Phenols, Poly
VERY HIGH: Based on measured LC50 values <1 mg/L in fish, daphnia and algae.
Freshwater fish (Salmo gairdneri) 96-hour
LC50 = 0.40 mg/L
(Experimental)
Freshwater fish (Lepomis macrochirus)
96-hour LC50 = 0.51 mg/L
(Experimental)
Freshwater fish (Pimephales promelas)
96-hour LC50 = 0.54 mg/L:
144-hour LC50 = 0.49 mg/L;
144-hour NOEC = 0.26 mg/L;
Flow-through test conditions; test
concentrations: 0.63, 0.45, 0.32, 0.26, and
0.19 mg active substance/L
(Experimental)
Freshwater fish (Cyprinus carpio) 96-hour
LC50 = 0.71 mg/L
48-hour LC50 = 0.80 mg/L
Static conditions; test concentrations:
0.42, 0.65, and 1.0 mg/L (nominal)
(Experimental)
Freshwater fish (Pimephales promelas}
96-hour LC50 = 710 (ig/L (0.71 mg/L)
(Experimental)
Freshwater fish (Pimephales promelas)
96-hour LC50 = 1,040 (ig/L (1.04 mg/L)
(Experimental)
Freshwater fish (Oncorhynchus mykiss)
96-hour LC50 = 1.1 mg/L
96-hour NOEC < 1.1 mg/L;
flow-through conditions; test
concentrations: 1.1 and 1.7 mg/L
Calmbacher, 1978 (as cited in
Simonsen et al., 2000)
EC, 2000
Suprenant, 1988 (as cited in EC,
2000; ECHA, 2013)
ECHA, 2013
ECOTOX, 2012
ECOTOX, 2012
Blankenship et al., 2003a;
ECHA, 2013
Insufficient information in primary
source.
Insufficient information in
secondary source.
Sufficient study details in primary
source.
Sufficient study details in a
secondary source; GLP study
following standard guidelines;
however, no analytical verification
of test compound concentrations.
Sufficient study summary reported
in a secondary source.
Sufficient study summary reported
in a secondary source.
Sufficient information in primary
source.
4-78
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
(measured); 1.2 and 1.8 mg/L (nominal)
(Experimental)
Freshwater fish (Danio rerio) 96-hour
EC50 = 1.1 mg/L
(Danio rerio) larvae 96-hour LC50 = 5.27
mg/L
(Experimental)
Freshwater fish (Danio rerio) LCioo = 1.5
mg/L
Exposure concentrations were 0, 0.002,
0.01, 0.05, 0.25, 0.75, and 1.5 mg/L;
nearly 100% of animals survived at
concentrations <1.5 mg/L, but some
embryos were malformed at 0.75 mg/L
(Experimental)
Freshwater fish (Lepomis macrochirus)
96-hour NOEC = 0.1 mg/L
(Experimental)
Freshwater fish (Salmo gairdneri} 96-hour
NOEC = 0.18mg/L
(Experimental)
Freshwater fish (Danio rerio) 96-hour
LC50 = 1.5 jig/L (0.0015 mg/L)
(Experimental)
Freshwater fish (Pimephales promelas}
96-hour LC50 = 60 (ig/L (0.06 mg/L)
(Experimental)
Freshwater fish (Pimephales promelas)
96-hour NOEC = 0.26 mg/L
(Experimental)
Freshwater fish (Oryzias latipes) 48-hour
LC50 = 8.2 mg/L
(Experimental)
Freshwater fish 96-hour LC50= 0.89 mg/L
REFERENCE
Chow etal., 2013
Hu et al., 2009
Simonsen et al., 2000
Simonsen et al., 2000
ECOTOX, 2012
ECOTOX, 2012
Simonsen et al., 2000
MITI, 1992 (as cited in EC,
2000)
ECOSARvl.ll
DATA QUALITY
Insufficient study details reported in
a primary source. EC50 is based on
hatching of zebrafish embryos.
Inconsistent with most other LC50
values reported for this compound.
Sufficient information in primary
source.
No study details in secondary
source.
No study details in secondary
source.
Insufficient study summary reported
in a secondary source.
Insufficient study summary reported
in a secondary source.
No study details in secondary
source.
No study details in secondary
source.
4-79
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Daphnid LC50
DATA
(Estimated)
ECOSAR: Phenols, Poly
Freshwater fish 96-hour LC50 = 2.3 mg/L
(Estimated)
ECOSAR: Neutral organics
Daphnia magna 48-hour EC50 = 0.60
mg/L
(Experimental)
Daphnia magna 48-hour LC50 = 0.96
mg/L; NOEC <0.32 mg/L
(Experimental)
Daphnia magna 48-hour LC50 >0.9 - <1.2
jig/L (>0.0009 - <0.0012 mg/L)
(Experimental)
Daphnia magna 24 and 4 8 -hour LC50
>1.8mg/L
48-hour NOEC =1.8 mg/L
flow-through test conditions
Test concentrations: 1.2 and 1.8 mg a.i./L
(nominal); average measured
concentration: 1.2 and 1.8 mg a.i./L
(Experimental)
Daphnia magna 48-hour LC50 = 7,900
Hg/L (7.9 mg/L)
(Experimental)
Daphnia magna 4 8 -hour LC50= 2.6 mg/L
(Estimated)
ECOSAR: Phenols, Poly
Daphnia magna 4 8 -hour LC50 = 1.7 mg/L
REFERENCE
ECOSAR v 1.11
Waaijers et al., 2013
Morrissey et al., 1978; Simonsen
et al., 2000; EC, 2000;
Anonymous, 2003
ECOTOX, 2012
Blankenship et al., 2003b;
ECHA, 2013
ECOTOX, 2012
ECOSAR v 1.11
ECOSAR v 1.11
DATA QUALITY
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Sufficient study details reported in a
primary source.
Sufficient information in primary
source.
Sufficient details reported in a
secondary source.
Sufficient information in primary
source. GLP study, following
standard guidelines, with analytical
verification of test compound
concentrations.
Sufficient details reported in a
secondary source.
Narcosis classes (neutral organics)
4-80
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
(Estimated)
ECOSAR: Neutral organics
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Other Invertebrate LC50
Saltwater Mysid shrimp 96-hour LC50 =
0.86-1.2 mg/L (in 1, 5 or 10 day old
shrimp, respectively)
(Experimental)
Goodman et al., 1988 (as cited
in EC, 2000)
Sufficient information in primary
source.
Green Algae EC s
Green Algae (Skeletonema costatum ) 72-
hour EC50 = 0.09 - 0.89 mg/L
(Experimental)
Walsh etal., 1987; EC, 2000;
Simonsen et al., 2000; ACC,
2006b
Limited details in secondary
sources.
Green Algae (Skeletonema costatum ) 72-
hour EC50 = 0.09 - 1.14 mg/L
(Experimental)
Walsh et al., 1987; ACC, 2006b
Sufficient details in primary source.
Green Algae (Thalassiosira pseudonana )
72-hour EC50 = 0.13-1.0 mg/L
(Experimental)
Walsh et al., 1987 (as cited in
ACC, 2006b)
Sufficient details in primary source.
Green algae 96-hour EC50 = 1.6 mg/L
(Estimated)
ECOSAR: Phenols, poly
ECOSAR v 1.11
Green algae 96-hour EC50 = 3.3 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSAR v 1.11
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
4-81
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Chronic Aquatic Toxicity
HIGH: Based on experimental LOECs and/or NOECs <1.0 mg/L in fish and daphnia.
Fish ChV
Freshwater fish (Pimephales promelas) 35
dayNOEC = 0.16mg/L;
LOEC = 0.31 mg/L;
MATC = 0.22 mg/L
Flow-through test conditions
Test concentrations: 0.025, 0.05, 0.1, 0.2,
and 0.4 mg a.i./L (nominal); 0.024, 0.04,
0.084, 0.16, and 0.31 mg a.i./L.
(measured)
(Experimental)
Surprenant, 1989; EC, 2000;
ACC, 2006b;ECHA, 2013;
Weltjeetal.,2013
Freshwater fish (Platichthys flesus) 105
day NOEC >0.8 \M (435 ng/mL or
0.000435 mg/L)
Test concentrations: 0; 0.001; 0.01; 0.1;
0.2; 0.4 and 0.8 jiM (0, 0.54, 5.4, 54.4,
109, 218, 435 ng/mL)
No adverse effect on behavior, survival,
growth rate, relative liver and gonad
weight. Increased levels of thyroid
hormone thyroxin (T4) with no signs of
altered thyroid gland activity.
(Experimental)
Zebra fish (Danio rerio) 2 8-day LCioo
(embryonic exposure) = 0.8 mg/L
Edema and hemorrhage, decreased heart
rate, edema of the trunk, tail malformation
Test concentrations: 0.27, 0.4, 0.54, 0.8,
1.6 mg/L
(Experimental)
Freshwater fish (Danio rerio) 30-day
partial life cycle test; LC^o = 1.5 (iM
(0.816 mg/L)
Exposure to 0, 0.023, 0.094, 0.375 and 1.5
. Reduced egg production (all
Kuiper et al., 2007a
McCormicketal., 2010
Kuiper etal., 2007b
Sufficient information in secondary
sources.
Sufficient details in primary source.
Sufficient details in primary source.
Sufficient study details reported in a
primary source.
4-82
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
exposure groups) and hatching ratios (all
groups other than 0.375 (iM). All larvae
died in the high dose group (1.5 (iM) and
mortality was preceded by retardation of
development.
(Experimental)
Freshwater fish ChV = 0.33 mg/L
(Estimated)
ECOSAR: Phenols, poly
ECOSARvl.ll
Freshwater fish ChV = 0.30 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSARvl.ll
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Daphnid ChV
Daphnia magnet 21 day EC50 >0.96 mg/L
21-day NOEC = 0.38 mg/L
21-day MATC >0.3 <0.98 mg/L
Flow-through test conditions.
Test concentrations: 0.13, 0.25, 0.5, 1.0,
2.0 mg/L (nominal); 0.037 - 0.078, 0.068 •
0.13, 0.14 - 0.26, 0.19 - 0.29, 0.65 - 1.3
mg/L (measured)
(Experimental)
ECHA, 2013
Sufficient study details in a
secondary source. GLP study with
analytical verification of test
compound concentrations;
methodology employed is well
described and designed specifically
to meet US EPA requirements.
Daphnia magna 21 day EC50 >0.98 mg/L
MATC = 0.54 mg/L
Flow-through test conditions.
Test concentrations: 0, 0.13, 0.25, 0.5, 1.0
and 2.0 (nominal)
(Experimental)
Suprenant, 1989 (as cited in EC,
2000; ACC, 2006b)
Sufficient study details
Daphnia magna ChV = 0.82 mg/L
(Estimated)
ECOSAR: Phenols, poly
ECOSARvl.ll
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Green Algae ChV
DATA
Daphnia magna ChV = 0.31 mg/L
(Estimated)
ECOSAR: Neutral organics
Green algae ChV: 0.31 mg/L
(Estimated)
ECOSAR: Phenols, poly
Green algae ChV = 5.6 mg/L
(Experimental)
Green algae ChV =1.5 mg/L
(Estimated)
ECOSAR: Neutral organics
Green Algae (Pseudokirchneriella
subcapitatd) 96-hour EC50 >5.6 mg/L
96-hour NOEC = 5.6 mg/L;
Static test conditions; Test concentrations:
0.60, 1.2, 2.4, 4.8, and 9.6 mg/L
(nominal); Mean measured concentration:
0.34, 0.76, 1.5, 3.0, and 5.6 mg/L.
(Experimental)
REFERENCE
ECOSAR v 1.11
ECOSAR v 1.11
Giddings, 1988
ECOSAR v 1.11
Giddings, 1988; Anonymous,
2003; ACC, 2006b; ECHA,
2013
DATA QUALITY
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
The effect level is greater than the
water solubility of 4. 16 mg/L; no
effects at saturation (NES) are
predicted.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Sufficient study details in secondary
sources. The effect levels are greater
than the water solubility of 4. 16
mg/L; no effects at saturation (NES)
are predicted.
ENVIRONMENTAL FATE
4-84
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Transport
Level III fugacity models incorporating available physical and chemical property data indicate that at
steady state, TBBPA is expected to be found primarily in soil and to a lesser extent, sediment. TBBPA is
expected to have low mobility in soil based on its calculated Koc. Therefore, leaching of TBBPA through
soil to groundwater is not expected to be an important transport mechanism. Estimated volatilization half-
lives for a model river and lake indicate that it will have low potential to volatilize from surface water. In
the atmosphere, TBBPA is expected to exist primarily in the particulate phase. Particulate phase TBBPA
will be removed from air by wet or dry deposition.
Henry's Law Constant (atm-
m3/mole)
1.47xl(Tu at 298K (Measured)
<1(T (Estimated)
Sediment/Soil
Adsorption/Desorption - Koc
l.lxlO5 at 6.8% organic carbon;
2.0xl05at 2.7% organic carbon;
2.3xl06 at 0.25% organic carbon
(Measured)
TBBPA is shown to adsorb to soil based
on laboratory soil mobility tests. TBBPA
was not eluted from the soil column after
11 pore volumes were displaced. No
quantitative values for the rate of soil
migration were measured. (Measured)
>3 0,000 (Estimated)
Level III Fugacity Model
Air = 0%
Water =1.4%
Soil = 64%
Sediment = 35% (Estimated)
Kuramochi et al., 2008
EPIv4.11;EPA, 2012
Breteler et al., 1989
Larsen et al., 2001 (as cited in
ACC, 2006a; ACC, 2006b)
Nonguideline study reported in a
secondary sources.
EPIv4.11;EPA, 2004
EPIv4.11
Based on the measured enthalpy of
fusion and melting point used to
calculate the sub-cooled liquid
vapor pressure and infinite dilution
activity coefficient.
Cutoff value for nonvolatile
compounds.
The Koc values were calculated
from the reported Kd values and the
percent organic carbon for each
sediment sample.
Estimated value is greater than
>3 0,000 using the Kow method from
KOCWIN v2.00; the high estimated
soil adsorption coefficient is
consistent with nonmobile
compounds.
EPI v 4.11 was used to estimate
environmental fate values in the
absence of experimental data.
Measured values (log Kow) from
experimental studies, were
4-85
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
incorporated into the estimations.
Persistence
HIGH: Experimental aerobic and anaerobic biodegradation studies in soil and sediment indicate that the
aerobic primary biodegradation half-life is less than 180 days, but not less than 60 days. Mineralization
under both aerobic and anaerobic conditions in soil and sediment is low, indicating that persistent
degradation products are formed. An experimental photolysis half-life of 24 minutes at pH 7.4 in water
indicates that TBBPA may photolyze rapidly to 4-isopropyl-2,6-dibromophenol, 4-isopropylene-2,6-
dibromophenol and 4-(2-hydroxyisopropyl)-2,6-dibromophenol; however, it is not anticipated to partition
significantly to water. Although adequate experimental data are not available, degradation of TBBPA by
hydrolysis is not expected to be significant as the functional groups present on this molecule do not tend to
undergo hydrolysis. The atmospheric half-life for the gas phase reactions of TBBPA is estimated at 3.6
days, though it is expected to exist primarily as a particulate in air.
Water
Aerobic Biodegradation
Passes Ready Test: No
Test method: OECD TG 301C: Modified
MITI Test (I)
No biodegradation was observed
according to a Japanese MITI test using
TBBPA (100 mg/L) in activated sludge
(30 mg/L) for 2 weeks. (Measured)
Volatilization Half-life for
Model River
>1 year (Estimated)
Volatilization Half-life for
Model Lake
>1 year (Estimated)
MITI, 1992; ACC, 2006a; ACC,
2006b; CERIJ, 2007
EPIv4.11
EPIv4.11
Guideline study reported in a
secondary source.
EPI v 4.11 was used to estimate
environmental fate values in the
absence of experimental data.
Measured values (log Kow) from
experimental studies, were
incorporated into the estimations.
EPI v 4.11 was used to estimate
environmental fate values in the
absence of experimental data.
Measured values (log Kow) from
experimental studies, were
incorporated into the estimations.
4-86
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Soil
Aerobic Biodegradation
Study results: 50%/65-93 days
Test method: Other
Half-life values reported for two aerobic
series using activated or digested sludge.
An aerobic soil half-life of 65 days was
calculated for TBBPA in the experiment
with activated sludge and 93 days in the
experiment with digested sludge.
(Measured)
Nyholmetal.,2010
Adequate guideline study.
Aerobic biodegradation of TBBPA was
measured in three soil types. After 64
days, the amount of TBBPA in the soil
ranged from 43.7 to 90.6%. 0.5 to 2.5% of
the applied radioactivity was recovered as
CO2, suggesting only partial
biodegradation. (Measured)
Fackler et al., 1989b (as cited in
ACC, 2006a)
Nonguideline study reported in a
secondary source.
Study results: 17.5%/6 months
Test method: Other
A transformation study in soil calculated
an aerobic DT50 of 5.3-7.7 days for the
soil extracts. The disappearance appears
to be predominantly due to binding to soil
and not due to biodegradation. Insufficient
material was extracted to identify the
transformation products. After 6 months,
17.5-21.6% of the dose was mineralized
in the aerobic soils. (Measured)
Schaefer and Stenzel, 2006c (as
cited in Environment Canada,
2013)
DT50 values were calculated for the
soil extracts; however, the majority
of the material remained bound to
soil and was not extracted. The non-
extractable (bound) radioactivity or
residues in the soil were not
characterized as called for in the
OECD guidelines. The abiotic
degradation rate under sterile
conditions was not estimated as
called for in the OECD guidelines.
Anaerobic Biodegradation
12-18% complete mineralization of
TBBPA in different soil types observed
after 4 months and 3-9% complete
mineralization observed after six months
in two separate series of anaerobic
biodegradation experiments.
Schaefer and Stenzel, 2006c (as
cited in Environment Canada,
2013)
Nonguideline studies reported in a
secondary source. Full anaerobic
conditions were not used throughout
the duration of the study in soil.
Study results: 50%/430 days
Test method: Other
Using a testing method similar to OECD
4-87
Nyholmetal.,2010
Adequate guideline study.
-------
Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Soil Biodegradation with
Product Identification
Sediment/Water
Biodegradation
DATA
Test Guideline 307. (Measured)
Study results: >43.7%/64 days
Test method: CO2 Evolution
Anaerobic biodegradation of TBBPA was
measured in three soil types. After 64
days, the amount of TBBPA remaining in
the soils ranged from 43.7 to 90.6%. Less
than 0.5% applied radioactivity was
recovered as CO2, suggesting only partial
biodegradation. (Measured)
Study results: 100%/45 days
Test method: Other
Under anaerobic conditions the results
initially reported TBBPA was mostly
dehalogenated within 10 days, and
complete dehalogenation to BPA was
achieved after 45 days. The resulting BPA
was not degraded anaerobically after 3
months. Di- and tribromobisphenol A
were observed as intermediates. Under
aerobic conditions, BPA was degraded to
4-hydroxybenzoic acid and 4-
hydroxyacetophenone. (Measured)
50%/84 days
Half-lives of 48 to 84 days were
determined in anaerobic natural river
sediment/water test system using 14C-
TBBPA. Less than 8% applied
radioactivity was recovered as CO2,
suggesting only partial biodegradation.
(Measured)
TBBPA was reductively dehalogenated to
BPA with tribromobisphenol A and
REFERENCE
Fackler et al., 1989b
Ronen and Abeliovich, 2000 (as
cited in ACC, 2006a; ACC,
2006b)
Fackler et al., 1989a (as cited in
ACC, 2006a; ACC, 2006b)
Ravit et al., 2005 (as cited in
Environment Canada, 2013)
DATA QUALITY
Adequate guideline study.
Nonguideline study reported in a
secondary report.
No data located.
Adequate guideline study reported
in a secondary source.
Adequate, nonguideline study.
4-88
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
dibromobisphenol A formed as
intermediates in sediment samples
through two species of salt marsh
macrophyte. (Measured)
An anaerobic mineralization and
transformation study in freshwater aquatic
sediment systems calculated an anaerobic
DT50 of 24-28 days for the whole system.
Very little mineralization was observed.
The transformation products included
BPA and 3 (Measured)
Schaefer and Stenzel, 2006a;
ACC, 2006b
Adequate nonguideline study.
An anaerobic mineralization and
transformation study in digester sludge
calculated an anaerobic DT50 of 19 days.
Very little mineralization was observed.
The transformation products included
BPA and 3 unidentified materials.
(Measured)
Schaefer and Stenzel, 2006b
Adequate nonguideline study.
Estuarine sediment; under methanogenic
conditions half-life was estimated to be
about 28 days. Under sulfate-reducing
conditions half-life was estimated to be 40
days. (Measured)
Voordeckers et al., 2002 (as
cited in ACC, 2006b)
Nonguideline study reported in a
secondary source.
Air
Atmospheric Half-life
3.6 days assuming 12-hr day/sunlight
(Estimated)
EPIv4.11
EPI v 4.11 was used to estimate
environmental fate values in the
absence of experimental data.
Measured values (log Kow) from
experimental studies, were
incorporated into the estimations.
Reactivity
Photolysis
50%/24 minutes
Photolysis half-lives in water of 16, 24,
and 350 minutes at pH values 10, 7.4, and
5.5, respectively, were measured under
fluorescent UV radiation representing
environmental wavelengths. Major
Eriksson et al., 2004 (as cited in
ACC, 2006a; ACC, 2006b; NTP.
2013)
Adequate nonguideline study.
4-89
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Hydrolysis
degradation products were 4-isopropyl-
2,6-dibromophenol, 4-isopropylene-2,6-
dibromophenol and 4-(2-
hydroxyisopropyl)-2,6-dibromophenol.
Other products include di- and
tribromobisphenol A, dibromophenol, 2,6-
dibromo-4-(bromoisopropylene)phenol,
2,6-dibromo-4-
(dibromoisopropylene)phenol and 2,6-
dibromo-1,4-hydroxybenzene. (Measured)
50%/33 hour
Photolysis of TBBPA in the presence of
UV light and hydroxyl radicals has also
been reported; TBBPA was no longer
detected after 5-6 days with an estimated
33 hour half-life. TBBPA decomposition
produced 2,4,6-tribromophenol and other
bromine containing compounds that were
not fully identified. (Estimated)
Eriksson and Jakobsson, 1998
(as cited in ACC, 2006a; ACC,
2006b)
Reported in a secondary source.
A study of TBBPA on silica gel was
reported. The wavelength studied was too
short to derive any environmental
conclusions. (Measured)
WHO, 1995 (as cited in ACC,
2006a)
Study details and test conditions
were not available. Reported in a
secondary source.
Reported half-lives in water of 6.6, 10.2,
25.9, and 80.7 days during summer,
spring, fall and winter, respectively.
(Measured)
WHO, 1995 (as cited in ACC,
2006a;NTP, 2013)
Study details and test conditions
were not available. Reported in a
secondary source.
Not a significant fate process (Estimated)
Wolfe and Jeffers, 2000;
Professional judgment
The substance does not contain
functional groups that would be
expected to hydrolyze readily under
environmental conditions.
Environmental Half-life
360 days (Estimated)
PBT Profiler vl.301: EPIv4.11
Half-life estimated for the
predominant compartment (soil), as
determined by EPI methodology.
Measured values from experimental
4-90
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
studies, were incorporated into the
estimations.
Bioaccumulation
MODERATE: The measured fish BCF and estimated BAF values are greater than 100 but less than 1,000.
Fish BCF
485 Cyprinus carpio
BCF ranges of 30 to 341 and 52 to 485
were measured in carp during an 8-week
study at concentrations of 80 (ig/L and 8
(ig/L, respectively. (Measured)
300 Pimephales promelas
A BCF of 1,200 was measured based on
total 14C radioactivity; however,
extraction and thin layer chromatograph
of the residue in the body of the fish
determined that only 24.9% of the 14C
radioactivity was due to TBBPA, with the
remainder due to metabolites, giving a
BCF of 300 for TBBPA. Elimination half-
life <24 hours for total 14C radioactivity.
(Measured)
170 Lepomis macrochirus
Bluegill sunfish were exposed to 14C-
TBBPA for 28 days to 0.0098 mg/L
(flow-through) followed by a 14-day
withdrawal period. The bioconcentration
factor (BCF) in edible tissue was 20 and
170 in visceral tissue. These BCF values
were based on 14C-residues and therefore
represent the sum total of parent
compound, any retained metabolites and
assimilated carbon. (Measured)
1,200 in Fathead minnows (Pimephales
promelas}
Reported for the BCF wet weight; BCF
value for lipid weight = 24,000; 24 days
MITI, 1992 (as cited in HSDB,
2013)
Dionne et al., 1989; ACC, 2006b
ACC, 2006b
Geyeretal., 2000
Adequate guideline study reported
in secondary source.
Adequate nonguideline study
reported in secondary source.
Adequate nonguideline study
reported in secondary source.
The BCF value includes all the
metabolites of the test substance, as
well as the test substance, 14C-
labeled chemical was used.
4-91
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
Other BCF
BAF
Metabolism in Fish
DATA
uptake (Measured)
960 in Zebrafish; reported as BCF wet
weight
BCF value for lipid weight = 28,300;
kinetic approach in outdoor experiment at
pH7.5. (Measured)
<3,190 in Chironomus tentans
BCF values of 243-51 1 (6.8% organic
carbon sediment); 487-1,140 (2.7%
organic carbon sediment) and 646-3,190
(0.25% organic carbon sediment).
(Measured)
148 in Eastern oyster (Measured)
130 (Estimated)
REFERENCE
Geyeretal., 2000
ACC, 2006b
ACC, 2006b
EPIv4.11
DATA QUALITY
Adequate nonguideline study
reported in secondary source.
Reported in a secondary source.
This is nonguideline study using a
non-standard test species and is not
able to be evaluated with the
assessment criteria.
Adequate nonguideline study
reported in secondary source with
limited study details.
EPI v 4. 1 1 was used to estimate
environmental fate values in the
absence of experimental data.
Measured values (log Kow of 4.54)
from experimental studies, were
incorporated into the estimations.
No data located.
4-92
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Tetrabromobisphenol A CASRN 79-94-7
PROPERTY/ENDPOINT
DATA
ENVIRONMENTAL MONITORING AND
Environmental Monitoring
Ecological Biomonitoring
Human Biomonitoring
REFERENCE DATA QUALITY
BIOMONITORING
TBBPA has been detected in the air of electronic recycling plants, although its presence in the air of this facility
likely arises from products where it was used as an additive flame retardant. Studies on the release of TBBPA
from PCBs after disposal in landfills were not available but would likely be low due to the low levels of
unreacted TBBPA. TBBPA was reported in air and marine sediment samples collected from several locations in
the Arctic. TBBPA was reported in indoor dust and air, soil, and food in Europe and the United States. It has
been reported in surface water in Japan, Germany, France, and the United Kingdom (Sellstrom and Jansson,
1995; Sjodin et al., 2001; Sjodin et al., 2003; PBS Corporation, 2006; Environment Canada, 2013).
TBBPA was reported in eel, salmon, perch, pike, cod, whiting, starfish, whelk, hermit crab, bottlenose dolphin,
bull shark, sharpnose shark, cormorant, harbour porpoise blubber, predatory birds, tern eggs and moss samples
from Norway. (Environment Canada, 2013)
TBBPA was detected in human umbilical cord, blood/serum, adipose, milk and hair samples (DeCarlo, 1979;
Thomsen et al., 2002; Peters, 2005; NTP, 2013).
4-93
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ACC (2002) An oral two generation reproductive, fertility, and developmental neurobehavioral study of tetrabromobisphenol A in rats. American
Chemistry Council. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8E.
ACC (2006a) HPV data summary and test plan for phenol, 4,4'-isopropylidenbis[2,6-dibromo- (tetrabromobisphenol A, TBBPA). Test plan
revision/updates, revised test plan. Robust summaries & test plans: Phenol, 4,4'-isopropylidenebis[2,6-dibromo-. American Chemistry Council
(ACC) Brominated Flame Retardant Industry Panel (BFRIP). Submitted under the HPV Challenge Program.
http://www.epa.gov/chemrtk/pubs/summaries/phenolis/cl3460rt3.pdf
ACC (2006b) Test plan revision/updates, revised summaries. Robust summaries & test plans: Phenol, 4,4'-isopropylidenebis[2,6-dibromo-.
American Chemistry Council Brominated Flame Retardant Industry Panel (BFRIP). Submitted under the HPV Challenge Program.
http://www.epa.gov/chemrtk/pubs/summaries/phenolis/cl3460rr3.pdf.
Anonymous (2003) Tetrabromobisphenol A. Beratergremium fuer umweltrelevante Altstoffe 239:122.
Antignac JP, Cariou R, Maume D, et al. (2008) Exposure assessment of fetus and newborn to brominated flame retardants in France: preliminary
data. Mol Nutr Food Res 52(2):258-265.
Arbeli Z and Ronen Z (2003) Enrichment of a microbial culture capable of reductive debromination of the flame retardant tetrabromobisphenol A,
and identification of the intermediate metabolites produced in the process. Biodegradation 14(6):385-395.
Ashford RD, ed (1994) Ashford's dictionary of industrial chemicals: properties, production, uses. London: Wavelength.
BRE (2009) Brominated flame retardants - Risks to UK drinking water sources. UK Department for Environment, Food, and Rural Affairs
(Defra).
Banasik, M. et al., (2009). Letter to the Editor. Tetrabromobisphenol A and model-derived risks for reproductive toxicity. Toxicology 260:150-
152.
Bergman A, Brouwer A, Ghosh M, et al. (1997) Risk of endocrine contaminants (RENCO). Aims and a summary of initial results. Organohalogen
Compounds 34:396-401.
Birnbaum LS and Staskal DF (2004) Brominated flame retardants: Cause for concern? Environ Health Perspect 112(1):9-17.
Blankenship A, van Hoven R, Krueger H (2003a) Tetrabromobisphenol A: A 96-hour flow-through acute toxicity test with the rainbow trout
(Oncorhynchus mykiss). Easton, MD: Wildlife International, Ltd.
http://yosemite.epa.gov/oppts/epatscat8.nsf/ALLIDS/3BC88861228D94E185256F32006B60FC/$FILE/84040000010.pdf?OpenElement.
4-94
-------
Blankenship A, van Hoven R, Krueger H (2003b) Tetrabromobisphenol A: A 48-hour flow-through acute toxicity test with the cladoceran
(Daphnia magnet). Easton, MD: Wildlife International, Ltd.
Breteler RJ, Hoberg JR, Garvey N, et al. (1989) The subchronic toxicity of sediment-sorbed tetrabromobisphenol A to Chironomus tentans under
flow-through conditions. Prepared by Springborn Laboratories, Inc. for Great Lakes Chemical Corporation. Submitted to the U.S. Environmental
Protection Agency under TSCA Section 4.
Brusick D and Weir RJ (1976) Mutagenicity evaluation of compound 279-117-2. Prepared by Litton Bionetics, Inc. for Great Lakes Chemical
Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
Buitenhuis C, Cenijn PC, van Velzen M, et al. (2004) Effects of prenatal exposure to hydroxylated PCB metabolites and some brominated flame
retardants on the development of rats. Organohalogen Compounds 66:3586—3592.
CCRIS (2013) 3,3',5,5'-Tetrabromibisphenyl A CASRN: 79-94-7. Chemical Carcinogenesis Research Information System. National Library of
Medicine. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen7CCRIS.
CERIJ (2007) [79-94-7]. Chemicals Evaluation and Research Institute, Japan. http://qsar.cerij.or.jp/cgi-bin/QSAR/e_r_text_query.cgi.
Calmbacher CW, Vilkas AG, Hutchinson C (1978) The acute toxicity of FMBP4A (tetrabromobisphenol A) to the rainbow trout, Salmo gairdneri
Richardson. Prepared by Union Carbide Corporation for Velsicol Chemical Corporation. Great Lakes Chemical Corporation. Submitted to the
U.S. Environmental Protection Agency under TSCA Section 8D.
Canton RF, Sanderson T, Nijmeijer S, et al. (2004) In vitro effects of selected brominated flame retardants on the adreno cortical enzyme
(CYP17): A novel endocrine mechanism of action? Organohalogen Compounds 66:3065-3069.
Cariou R, Antignac JP, Zalko D, et al. (2008) Exposure assessment of French women and their newborns to tetrabromobisphenol-A: occurrence
measurements in maternal adipose tissue, serum, breast milk and cord serum. Chemosphere 73(7):1036-1041.
Chow WS, Chan WK, Chan KM (2013) Toxicity assessment and vitellogenin expression in zebrafish (Danio rerio) embryos and larvae acutely
exposed to bisphenol A, endosulfan, heptachlor, methoxychlor and tetrabromobisphenol A. J Appl Toxicol 33(7):670-678.
Christiansen LB, Pedersen KL, Pedersen SN, et al. (2000) In vivo comparison of xenoestrogens using rainbow trout vitellogenin induction as a
screening system. Environ Toxicol Chem 19(7): 1867-1874.
Churchwell DB and Ellis A (2007) Process safety test results and interpretation. Plainsboro, NJ: Chilworth Technology.
Curren RD, Kmetz J, Schechtman LM (1981) Activity of T1685 in the Salmonella/microsomal assay for bacterial mutagenicity final report.
Prepared by Microbiological Associates for Ethyl Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
4-95
-------
Danish EPA (1999) Appendix 3. Physical-chemical properties of brominated flame retardants. Brominated flame retardants: Substance flow
analysis and assessment of alternatives. Danish Environmental Protection Agency.
http://www2.mst.dk/common/Udgivramme/Frame.asp?http://www2.mst.dk/udgiv/publications/1999/87-7909-416-3/html/bil03_eng .htm.
Darnerud PO (2003) Toxic effects of brominated flame retardants in man and in wildlife. Environ Int 29(6):841-853.
DeCarlo VJ (1979) Studies on brominated chemicals in the environment. Ann N Y Acad Sci 320:678-681.
Dean WP, Jessup DC, Epstein WL, et al. (1978a) Modified Draize multiple insult test in humans. Prepared by International Research and
Development Corporation for Velsicol Chemical Corporation. Great Lakes Chemical Corporation. Submitted to the U.S. Environmental Protection
Agency under TSCA Section 8D.
Dean WP, Jessup DC, Thompson G, et al. (1978b) Acute oral toxicity (LD50) study in mice. Prepared by International Research and Development
Corporation for Velsicol Chemical Corporation. Great Lakes Chemical Corporation. Submitted to the U.S. Environmental Protection Agency
under TSCA Section 8D.
Dean WP, Jessup DC, Thompson G, et al. (1978c) Dermal sensitization study in the albino guinea pig. Prepared by International Research and
Development Corporation for Velsicol Corporation. Great Lakes Chemical Corporation. Submitted to the U.S. Environmental Protection Agency
under TSCA Section 8D.
Dionne E, Fackler PH, Grandy KA (1989) Bioconcentration and elimination of C-residues by fathead minnow (Pimephales promelas) exposed to
tetrabromobisphenol A (final report) with cover letter dated 031789. Prepared by Springborn Laboratories, Inc. for Great Lakes Chemical
Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA, Section 4.
Doyle RL and Elsea JR (1966) Acute toxicity and irritation studies on tetrabromobisphenol-A. Prepared for Hill Top Research, Inc. for Michigan
Chemical Corporation. Great Lakes Chemical Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
EC (2000) [2,2',6,6'-tetrabromo-4,4'-isopropylidenediphenol CasNo. 79-94-7]. IUCLID dataset. European Commission. European Chemicals
Bureau.
ECHA (2013) 2,2',6,6'-Tetrabromo-4,4'-isopropylidenediphenol. Registered substances. European Chemicals Agency.
http://apps.echa.europa.eu/registered/data/dossiers/DISS-9d928727-4180-409d-e044-00144f67d249/DISS-9d928727-4180-409d-e044-
00144f67d249_DISS-9d928727-4180-409d-e044-00144f67d249.html.
ECOSAR Ecological Structure Activity Relationship (ECOSAR). Estimation Programs Interface (EPI) Suite for Windows, Version 1.11.
Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency, http://www.epa.gov/oppt/newchems/tools/21ecosar.htm.
ECOTOX (2012) ECOTOX database. U.S. Environmental Protection Agency, http://cfpub.epa.gov/ecotox/.
4-96
-------
EPA (1999) Determining the adequacy of existing data. High Production Volume (HPV) Challenge. Washington, DC: U.S. Environmental
Protection Agency, http://www.epa.gov/hpv/pubs/general/datadeqm.pdf.
EPA (2004) Pollution prevention (P2) framework. Washington, DC: U.S. Environmental Protection Agency, Office of Pollution Prevention and
Toxics, http://www.epa.gov/oppt/sf/pubs/p2frame-june05a2.pdf
EPA (2010) TSCA new chemicals program (NCP) chemical categories. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/newchems/pubs/npcchemicalcategories.pdf
EPA (2012) Interpretive assistance document for assessment of discrete organic chemicals sustainable futures summary assessment. Washington
DC: U.S. Environmental Protection Agency. http://www.epa.gov/oppt/sf/pubs/iad_discretes_docjune2012.pdf
EPI Estimation Programs Interface (EPI) Suite, Version 4.11. Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency.
http://www.epa.gov/opptintr/exposure/pubs/episuitedl.htm.
ESIS (2012) European chemical Substances Information System. European Commission, http://esis.jrc.ec.europa.eu/.
EU (2006) European Union risk assessment report: 2,2',6,6'-Tetrabromo-4,4'-isopropylidenediphenol (tetrabromobisphenol-A or TBBP-A) Part II
- Human Health CAS No: 79-94-7 EINECS No: 201-236-9. Luxembourg: European Union. Office for Official Publications of the European
Communities. http://esis.jrc.ec.europa.eu/doc/risk_assessment/REPORT/tbbpaHHreport402.pdf
Environment Canada (2013) Screening assessment report. Phenol, 4,4'-(l-methylethylidene) bis[2,6-dibromo-. Chemical Abstracts Service
Registry Number 79-94-7. Ethanol, 2,2'-[(l-methylethylidene)bis[(2,6-dibromo-4,l-phenylene)oxy]]bis. Chemical Abstracts Service Registry
Number 4162-45-2. Benzene, l,l'-(l-methylethylidene)bis[3,5-dibromo-4-(2-propenyloxy)-. Chemical Abstracts Service Registry Number 25327-
89-3. Environment Canada. Health Canada. http://www.ec.gc.ca/ese-ees/BEE093E4-8387-4790-A9CD-C753B3E5BFAD/FSAR_TBBPA_EN.pdf
Eriksson J and Jakobsson E (1998) Decomposition of tetrabromobisphenol A in the presence of UV-light and hydroxyl radicals. Organohalogen
Compounds 35:419-422.
Eriksson J, Rahm S, Green N, et al. (2004) Photochemical transformations of tetrabromobisphenol A and related phenols in water. Chemosphere
54:117-126.
Eriksson P, Jakobsson E, Fredriksson A (2001) Brominated flame retardants: A novel class of developmental neurotoxicants in our environment?
Environ Health Perspect 109:903-908.
Eriksson P, Jakobsson E, Fredriksson A (1998) Developmental neurotoxicity of brominated flame retardants, polybrominated diphenyl ethers, and
tetrabromo-bis-phenol A. Organohalogen Compounds 35:375-377.
4-97
-------
Fackler PH, Hartley DA, Shepherd SP, et al. (1989a) Determination of the biodegradability in a sediment/soil microbial system on
tetrabromobisphenol A (Draft) with cover letter dated 082389. Prepared by Springborn Laboratories, Inc. for Great Lakes Chemical Corporation.
Submitted to the US EPA under TSCA Section 4.
Fackler PH, Van de Ruit R, Conroy WJ (1989b) Determination of the biodegradability of tetrabromobisphenol A in soil under anaerobic
conditions (final report) with attachments and cover letter dated 013189. Prepared by Springborn Life Sciences, Inc. for Great Lakes Chemical
Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 4.
Fini JB, Le Mevel S, Palmier K, et al. (2012) Thyroid hormone signaling in the Xenopus laevis embryo is functional and susceptible to endocrine
disruption. Endocrinology 153(10):5068-5081.
Fujitani T, Tada Y, Takahashi H, et al. (2007) Distribution of tetrabromobisphenol A and its conjugates in mice. Tokyo-to Kenko Anzen Kenkyu
Senta Kenkyu Nenpo 57:367-370.
FukudaN, Ito Y, Yamaguchi M, et al. (2004) Unexpected nephrotoxicity induced by tetrabromobisphenol A in newborn rats. Toxicol Lett
150:145-155.
Gerecke AC, Giger W, Hartmann PC, et al. (2006) Anaerobic degradation of brominated flame retardants in sewage sludge. Chemosphere
64(2):311-317.
Geyer HJ, Rimkus GG, Scheunert I, et al. (2000) Bioaccumulation and occurrence of endocrine-disrupting chemicals (EDCS), persistent organic
pollutants (POPS), and other organisms including humans. In: Beek B, eds. Handbook of environmental chemistry, Vol. 2, Part J
Bioaccumulation. Berlin, Germany: Springer-Verlag.: 1-166.
Ghisari M and Bonefeld-Jorgensen EC (2005) Impact of environmental chemicals on the thyroid hormone function in pituitary rat GH3 cells. Mol
Cell Endocrinol 244(1-2):31-41.
Giddings J (1988) Toxicity of tetrabromobisphenol A to the freshwater green alga Selenastrum capricornutum. Wareham, MA: Springborn Life
Sciences, Inc.
Goldenthal El, Jessup DC, Geil RG, et al. (1979) Three-week dermal toxicity study in rabbits. Prepared by International Research and
Development Corporation for Velsicol Chemical Company. Great Lakes Chemical Company. Submitted to the U.S. Environmental Protection
Agency under TSCA Section 8D.
Goldenthal El, Jessup DC, Rodwell DE (1978) Pilot teratogenicity study in rats. International Research and Development Corporation for Velsicol
Chemical Corporation. Great Lakes Chemical Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
Goodman L, Cripe G, Moody P, et al. (1988) Acute toxicity of malathion, tetrabromobisphenol A and tributyltin chloride to mysids (Mysidopsis
bahid) of three ages. Bull Environ Contam Toxicol 41:746-753.
4-98
-------
Gudi R and Brown CM (2001) In vitro mammalian chromosome aberration test. In: Initial submission: Ltr from ACC to USEPA submitting health
effects & physical chemistry studies of tetrabromobisphenol A, with attachments & dated 121101. Prepared by BioReliance for American
Chemistry Council. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8E.
HSDB (2013) 2,2',6,6'-Tetrabromobisphenol A CASRN: 79-94-7. Hazardous Substances Data Bank. National Library of Medicine.
http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen7HSDB.
Hakk H, Larsen G, Bergman A, et al. (2000) Metabolism excretion and distribution of the flame retardant tetrabromobisphenol-A in conventional
and bile-duct cannulated rats. Xenobiotica 30(9):881-890.
Hardy ML and Smith RL (1999) The potential of certain brominated flame retardants for persistence, bioaccumulation, or long range transport.
Prepr Ext Abst Div Environ Chem Am Chem Soc 39:191-194.
Hu J, Liang Y, Chen M, et al. (2009) Assessing the toxicity of TBBPA and HBCD by zebrafish embryo toxicity assay and biomarker analysis.
Environ Toxicol 24(4):334-342.
Huang GY, Ying GG, Liang YQ, et al. (2013) Hormonal effects of tetrabromobisphenol A using a combination of in vitro and in vivo assays.
Comp Biochem Physiol C Toxicol Pharmacol 157(4):344-351.
Kurd T and Whalen MM (2011) Tetrabromobisphenol A decreases cell-surface proteins involved in human natural killer (NK) cell-dependent
target cell lysis. 8:219-227.
ICL (2013) Safety data sheet: product name-FR-1524 [TBBA]. ICL Industrial Products.
Jagannath DR and Brusick DJ (1977) Mutagenicity evaluation of tetrabromobisphenol A (BP4-A) final report. Prepared by Litton Bionetics, Inc.
for Velsicol Chemical Company. Great Lakes Chemical Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA
Section 8D.
Jagnytsch O, Opitz R, Lutz I, et al. (2006) Effects of tetrabromobisphenol A on larval development and thyroid hormone-regulated biomarkers of
the amphibian Xenopus laevis. Environ Res 101(3):340-348.
Kang MJ, Kim JH, Shin S, et al. (2009) Nephrotoxic potential and toxicokinetics of tetrabromobisphenol A in rat for risk assessment. J Toxicol
Environ Health A 72(21-22): 1439-1445.
Kitagawa Y, Takatori S, Oda S, et al. (2003) Detection of thyroid hormone receptor-binding activities of chemicals using a yeast two-hybrid assay.
J Health Sci 49(2): 99-104.
4-99
-------
Kitamura S, Jinno N, Ohta S, et al. (2002) Thyroid hormonal activity of the flame retardants tetrabromobisphenol A and tetrachlorobisphenol A.
Biochem Biophys Res Commun 293(l):554-559.
Kitamura S, Kato T, lida M, et al. (2005a) Anti-thyroid hormonal activity of tetrabromobisphenol A, a flame retardant, and related compounds:
Affinity to the mammalian thyroid hormone receptor, and effect on tadpole metamorphosis. Life Sci 76(14): 1589-1601.
Kitamura S, Suzuki T, Sanoh S, et al. (2005b) Comparative study of the endocrine-disrupting activity of bisphenol A and 19 related compounds.
Toxicol Sci 84:249-259.
Knudsen GA, Kuester RK, Rodriguez VP, et al. (2006) Disposition and excretion of tetrabromobisphenol A bis[2,3-dibromopropyl ether]
(TBBPA-DBPE) in male Fischer-344 rats. Toxicol Sci 90(1-S):122.
Knudsen GA, Sanders JM, Sadik AM, et al. (2013) Disposition and kinetics of tetrabromobisphenol A (TBBPA) in female Wistar Han rats.
Toxicology.
Kuester RK, Solyom AM, Rodriguez VP, et al. (2007) The effects of dose, route, and repeated dosing on the disposition and kinetics of
tetrabromobisphenol A in male F-344 rats. Toxicol Sci 96:237-245.
Kuiper RV, Canton RF, Leonards PE, et al. (2007a) Long-term exposure of European flounder (Platichthys flesus) to the flame-retardants
tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCD). Ecotoxicol Environ Saf 67(3):349-360.
Kuiper RV, van den Brandhof EJ, Leonards PE, et al. (2007b) Toxicity of tetrabromobisphenol A (TBBPA) in zebrafish (Danio rerio) in a partial
life-cycle test. Arch Toxicol 81(1): 1-9.
Kuramochi H, Kawamoto K, Miyazaki K, et al. (2008) Determination of physicochemical properties of tetrabromobisphenol A. 27:2413-2418.
Larsen G, Casey F, Bergman A, et al. (2001) Mobility, sorption, and fate of tetrabromobisphenol A (TBBPA) in loam soil and sand. Abstracts of
the 2nd International Workshop on Brominated Flame Retardants, Stockholm, Sweden.:213-216.
http://info.ngwa.org/GWOL/pdf/pdf/012572667.pdf.
Legler J, Cenijn P, Malmberg T, et al. (2002) Determination of the endocrine disrupting potency of hydroxylated PCBS and flame retardants with
in vitro bioassays. Organohalogen Compounds 56:53-56.
Lezotte F and Nixon W (2001) Determination of the vapor pressure of tetrabromobisphenol A using the spinning rotor gauge method. Easton, MD:
Wildlife International, Ltd.
Lezotte F and Nixon W (2002) Determination of the dissociation constant of tetrabromobisphenol A. Easton, MD: Wildlife International, Ltd.
4-100
-------
Lilienthal H, Verwer CM, van der Ven LT, et al. (2008) Exposure to tetrabromobisphenol A (TBBPA) in Wistar rats: neurobehavioral effects in
offspring from a one-generation reproduction study. Toxicology 246(l):45-54.
Lilienthal H, van der Ven L, Hack A, et al. (2009) Neurobehavioral Effects in Relation to Endocrine Alterations Caused by Exposure to
Brominated Flame Retardants in Rats-Comparison to Fob/chlorinated Biphenyls. Hum Ecol Risk Assess 15(l):76-86.
MITI (1992) 2,2-Bis(4'-hydroxy-3',5'-dibromophenyl)propane. Biodegradation and bioaccumulation data of existing chemicals based on the CSCL
Japan. Tokyo: Chemicals Inspection &Testing Institute, Japan. Ministry of International Trade & Industry. Japan Chemical Industry Ecology-
Toxicology & Information Center.:4-14.
MPI Research (2002) A 90-day oral toxicity study of tetrabromobisphenol A in rats with a recovery group.
MacGregor J and Nixon W (2001) Determination of the n-octanol/water partition coefficient of tetrabromobisphenol A. Easton, MD: Wildlife
International, Ltd.
MacGregor J and Nixon W (2002) Determination of water solubility of tetrabromobisphenol A. Easton, MD: Wildlife International, Ltd.
Mallory VT, Naismith RW, Matthews RJ (1981a) Acute eye irritation test in rabbits PH 421-ET-001-81 tetrabromo bisphenol-A Lot #R6/FD2.
Prepared by Pharmakon Laboratories for Ethyl Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
Mallory VT, Naismith RW, Matthews RJ (1981b) Acute oral toxicity study in rats (14 day) PH402-ET-001-81 Tetrabromo bisphenol-A Lot
#R6/FD2. Prepared by Pharmakon Laboratories for Ethyl Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA
Section 8D.
Mallory VT, Naismith RW, Matthews RJ (1981c) Delayed contact hypersensitivity in guinea pigs PH424-ET-001-81 tetrabromo bisphenol-A Lot
# R6/FD2. Prepared by Pharmakon Laboratories for Ethyl Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA
Section 8D.
Mallory VT, Naismith RW, Matthews RJ (1981d) Primary dermal irritation study in rabbits (IRIG/FIFRA)420-ET-001-81 tetrabromo bisphenol-A
Lot #R6/FD2. Prepared by Pharmakon Laboratories for Ethyl Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA
Section 8D.
McCormick JM, Paiva MS, Haggblom MM, et al. (2010) Embryonic exposure to tetrabromobisphenol A and its metabolites, bisphenol A and
tetrabromobisphenol A dimethyl ether disrupts normal zebrafish (Danio rerio) development and matrix metalloproteinase expression. Aquat
Toxicol 100(3):255-262.
Morrissey AE, Vilkas AG, Hutchinson C (1978) Acute toxicity of FMBP4A (tetrabromobisphenol A) to the water flea Daphnia magna Straus.
Prepared by Union Carbide Corporation for Velsicol Chemical Corporation. Great Lakes Chemical Corporation. Submitted to the U.S.
Environmental Protection Agency under TSCA Section 8D.
4-101
-------
MPI. (2001) An oral prenatal developmental toxicity study with tetrabromobisphenol A in rats. Initial submission: Ltr from ACC to USEPA
Submitting health effects & physical chemistry studies of tetrabromobisphenol A, with attachments & dated 121101. Prepared by MPI Research
for American Chemistry Council. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8E.
Noda T, Morita S, Ohgaki S, et al. (1985) Safety evaluation of chemicals for use in household products (VII) teratological studies on
tetrabromobisphenol-A in rats. Annual report of the Osaka Institute of Public Health and Environmental Sciences 48, 106-112.NOTOX (2000)
Determination of the water solubility of tetrabromobisphenol A. Hertogenbosch: NOTOX B. V.
NTP (2011) Search Result for Search Term '21850-44-2' [tetrabromobisphenol A-bis(2,3-dibromopropyl ether)]. http://ntp-
apps.niehs.nih.gov/ntp_tox/index.cfm?searchterm=21850-44-2&fuseaction=ntpsearch.searchresults.
NTP (2012) Tetrabromobisphenol A. Testing status of agents at NTP. National Toxicology Program, Department of Health and Human Services.
http://ntp.niehs.nih.gov/?objectid=BD5EA5A9-123F-7908-7B9B7C4D3356ClCF.
NTP (2013) NTP technical report on the toxicology studies of tetrabromobisphenol A (CAS No. 79-94-7) in F344/NTac rats and B6C3F1/N mice
and toxicology and carcinogenesis studies of tetrabromobisphenol A in Wistar Han [Crl:WI(Han)] rats and B6C3F1 mice (gavage studies).
National Toxicology Program, National Institutes of Health. http://ntp.niehs.nih.gov/NTP/About_NTP/TRPanel/2013/October/DRAFT_TR-
587.pdf.
Nakajima A, Saigusa D, Tetsu N, et al. (2009) Neurobehavioral effects of tetrabromobisphenol A, a brominated flame retardant, in mice. Toxicol
Lett 189(l):78-83.
Nishihara T, Nishikawa J, Kanayama T, et al. (2000) Estrogenic activities of 517 chemicals by yeast two-hybrid assay. J Health Sci 46(4):282-298.
Nyholm JR, Lundberg C, Andersson PL (2010) Biodegradation kinetics of selected brominated flame retardants in aerobic and anaerobic soil.
Environ Pollut 158(6):2235-2240.
Olsen CM, Meussen-Elholm ET, Samuelsen M, et al. (2003) Effects of the environmental oestrogens bisphenol A, tetrachlorobisphenol A,
tetrabromobisphenol A, 4-hydroxybiphenyl and 4,4'-dihydroxybiphenyl on oestrogen receptor binding, cell proliferation and regulation of
oestrogen sensitive proteins in the human breast cancer cell line MCF-7. Pharmacol Toxicol 92(4): 180-188.
OncoLogic (2008) Version 7.0. U.S. Environmental Protection Agency and LogiChem, Inc.
PBS Corporation (2006) Unpublished results of testing done to detect free TBBPA from extraction of prepreg sample Nelco N4000-6. Singapore:
PBT Profiler Persistent (P), Bioaccumulative (B), and Toxic (T) Chemical (PBT) Profiler, Version 1.301. Washington, DC: U.S. Environmental
Protection Agency, www.pbtprofiler.net.
4-102
-------
Peters RJB (2005) Man-made chemicals in maternal and cord blood. Apeldoorn, The Netherlands: TNO Built Environment and Geosciences.
http://www.greenpeace.Org/international/Global/international/planet-2/report/2005/9/man-made-chemicals-in-maternal.pdf.
Quast JF, Humiston CG, Schwetz BA (1975) Results of a 90-day toxicological study in rats given tetrabromobisphenol A in the diet. The Dow
Chemical Company. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D by Dow Chemical Company.
Ravit B, Ehrenfeld JG, Haggblom MM (2005) Salt marsh rhizosphere affects microbial biotransformation of the widespread halogenated
contaminant tetrabromobisphenol-A (TBBPA). Soil Biol Biochem 37:1049-1057.
Ronen Z and Abeliovich A (2000) Anaerobic-aerobic process for microbial degradation of tetrabromobisphenol A. Appl Environ Microbiol
66:2372-2377.
Roper CS (2005) The in vitro percutaneous absorption of radiolabelled tetrabromobisphenol A (TBBPA) through human skin. Tranent, Scotland:
Inveresk.
Roper CS, Madden S, Biesemeier JA, et al. (2007) The in vitro percutaneous absorption of radiolabelled tetrabromobisphenol A (TBBPA) through
human skin. Organohalogen Compounds 69:580/581-580/582.
Roy P, Salminen H, Koskimies P, et al. (2004) Screening of some anti-androgenic endocrine disrupters using a recombinant cell-based in vitro
bioassay. J Steroid Biochem Mol Biol 88(2): 157-166.
Saegusa Y, Fujimoto H, Woo GH, et al. (2009) Developmental toxicity of brominated flame retardants, tetrabromobisphenol A and 1,2,5,6,9,10-
hexabromocyclododecane, in rat offspring after maternal exposure from mid-gestation through lactation. Reprod Toxicol 28:456-467.
Saegusa Y, Fujimoto H, Woo GH, et al. (2012) Transient aberration of neuronal development in the hippocampal dentate gyrus after
developmental exposure to brominated flame retardants in rats. Arch Toxicol 86(9): 1431-1442.
Sakai H, Yamada-Okabe T, Kashima Y, et al. (2003) Effects of brominated flame retardants on transcriptional activation mediated by thyroid
hormone receptor. Organohalogen Compounds 61:215-218.
Schaefer E and Stenzel J (2006a) Anaerobic transformation of radiolabeled (14C) tetrabromobisphenol A in freshwater aquatic sediment systems.
Easton, MD: Wildlife International, Ltd.
Schaefer E and Stenzel J (2006b) Mineralization and transformation of radiolabeled (14C)tetrabromobisphenol A in anaerobic digester sludge.
Easton, MD: Wildlife International, Ltd.
Schaefer E and Stenzel J (2006c) Tetrabromobisphenol A: Aerobic and anaerobic transformation in soil. Easton, MD: Wildlife International, Ltd.
4-103
-------
Schauer UMD, Volkel W, Dekant W (2006) Toxicokinetics of tetrabromobisphenol A in humans and rats after oral administration. Toxicol Sci
91:49-58.
Sellstrom U and Jansson B (1995) Analysis of tetrabromobisphenol A in a product and environmental samples. Chemosphere 31(4):3085-3092.
Simon VF, Poole DC, Newell GW, et al. (1979) In vitro microbiological mutagenicity studies of Dow Chemical Company compounds. The Dow
Chemical Company. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
Simonsen FA, Stavnsbjerg M, Moller LM, et al. (2000) Brominated flame retardants; toxicity and ecotoxicity. Centre for Integrated Environment
and Toxicology.
Sjodin A, Carlsson H, Thuresson K, et al. (2001) Flame retardants in indoor air at an electronics recycling plant and at other work environments.
Environ Sci Technol 35(3):448-454.
Sjodin A, Patterson D, Bergman A (2003) A review on human exposure to brominated flame retardants - particularly polybrominated diphenyl
ethers. Environ Int 29:829-839.
Solyom AM, Kuester RK, Rodriguez VP, et al. (2006) Disposition Of Tetrabromobisphenol A (TBBPA) In Male Fischer-344 Rats. Toxicol Sci
90(1-S):122.
Stenger VA (1978) Bromine compounds. Kirk-Othmer encyclopedia of chemical technology. 3rd ed. New York, NY: Wiley-Interscience.:243-
263.
Sterner W (1967a) Acute eye irritation study on rabbits of tetrabromobisphenol A. Prepared by International Bio-Research, Inc. for Great Lakes
Chemical Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
Sterner W (1967b) Acute inhalation toxicity study of tetrabromobisphenol A. Prepared by International Bio-Research, Inc. for Great Lakes
Chemical Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
Sterner W (1967c) Acute oral toxicity of tetrabromobisphenol A to rats. Prepared by International Bio-Research, Inc. for Great Lakes Chemical
Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
Strain GM, Banasik M, Hardy M, et al. (2009) Tetrabromobisphenol A (TBBPA) and model-derived risks for neurobehavioral effects in offspring
from a one-generation reproduction study. Toxicology 260(1-3): 155-157; author reply 158-161.
Suprenant DC (1988) Acute toxicity of tetrabromobisphenol A to fathead minnow (Pimephales promelas) under flow-through conditions with
attachments and cover letter dated 111788. Wareham, MA: Prepared by Springborn Laboratories, Inc. for Great Lakes Chemical Corporation.
Submitted to the U.S. Environmental Protection Agency under TSCA Section 4.
4-104
-------
Suprenant DC (1989) The chronic toxicity of tetrabromobisphenol A (TBBPA) to Daphnia magna under flow-through conditions (Final report)
with cover letter dated 081989. Prepared by Springborn Laboratories, Inc. for Great Lakes Chemical Corporation. Submitted to the U.S.
Environmental Protection Agency under TSCA Section 4.
Surprenant D (1989) The toxicity of tetrabromobisphenol A (TBBPA) to fathead minnow (Pimephales promelas) embryos and larvae. Wareham,
MA: Springborn Life Sciences, Inc.
Tada Y and Fujitani T (2006) Effects of tetrabromobisphenol A, a brominated flame retardant, in ICR mice after prenatal and postnatal exposure.
Food Chem Toxicol 44(8): 1408-1413.
Tada Y, Fujitani T, Ogata A, et al. (2007) Flame retardant tetrabromobisphenol A induced hepatic changes in ICR male mice. Environ Toxicol
Pharmacol 23(2): 174-178.
Tada Y, Sakamoto Y, Yano N, et al. (2005) Effects of neonatal exposure of tetrabromobisphenol A, a flame retardant, in the reproductive organ of
SD male rats. Tokyo-to Kenko Anzen Kenkyu Senta Kenkyu Nenpo 55:331-334.
Thomsen C, Lundanes E, Becher G (2002) Brominated flame retardants in archived serum samples from Norway: A study on temporal trends and
the role of age. Environ Sci Technol 36:1414-1418.
Tobe M, Kurokawa Y, Nakaji Y, et al. (1986) Subchronic toxicity study of tetrabromobisphenol-A: Report to the Ministry of Health and Welfare.
Van der Ven LT, Van de Kuil T, Verhoef A, et al. (2008) Endocrine effects of tetrabromobisphenol-A (TBBPA) in Wistar rats as tested in a one-
generation reproduction study and a subacute toxicity study. Toxicology 245(l-2):76-89.
Viberg H and Eriksson P (2011) Differences in neonatal neurotoxicity of brominated flame retardants, PBDE 99 and TBBPA, in mice. Toxicology
289(l):59-65.
Voordeckers JW, Fennell DE, Jones K, et al. (2002) Anaerobic biotransformation of tetrabromobisphenol A, tetrachlorobisphenol A, and
bisphenol A in estuarine sediments. Environ Sci Technol 36(4):696-701.
WHO (1995) Environmental Health Criteria 172. Tetrabromobisphenol A and derivatives. International Programme on Chemical Safety, World
Health Organization. http://www.inchem.org/documents/ehc/ehc/ehc 172 .htm.
Waaijers SL, Hartmann J, Soeter AM, et al. (2013) Toxicity of new generation flame retardants to Daphnia magna. Sci Total Environ 463-
464:1042-1048.
Walsh GE, Yoder MJ, McLaughlin LL, et al. (1987) Responses of marine unicellular algae to brominated organic compounds in six growth media.
Ecotoxicol Environ Saf 14:215-222.
4-105
-------
Watanabe W, Shimizu T, Sawamura R, et al. (2010) Effects of tetrabromobisphenol A, a brominated flame retardant, on the immune response to
respiratory syncytial virus infection in mice. 10:393-397.
Wazeter FX, Goldenthal ET, Geil RG, et al. (1975) Tetrabromobisphenol A: Fourteen day inhalation toxicity study in rats. Prepared by
International Research and Development Corporation. Great Lakes Chemical Corporation. Submitted to the U.S. Environmental Protection
Agency under Section 8D.
Wazeter RX, Goldenthal El, Geil RG (1972) Twenty-eight day toxicity study in rats. Prepared by International Research and Development
Corporation for Great Lakes Chemical Corporation. Submitted to the U.S. Environmental Protection Agency under TSCA Section 8D.
Weltje L, Simpson P, Gross M, et al. (2013) Comparative acute and chronic sensitivity offish and amphibians: a critical review of data. Environ
Toxicol Chem 32(5):984-994.
Williams AL and DeSesso JM (2010) The potential of selected brominated flame retardants to affect neurological development. 13:411-448.
Wolfe N and Jeffers P (2000) Hydrolysis. In: Boethling RS, Mackay D, eds. Handbook of property estimation methods for chemicals
Environmental and Health Sciences. Boca Raton, FL: Lewis Publishers.:311-333.
Zatecka E, Ded L, Elzeinova F, et al. (2013) Effect of tetrabromobisphenol A on induction of apoptosis in the testes and changes in expression of
selected testicular genes in CD1 mice. Reprod Toxicol 35:32-39.
van der Ven L, Lilienthal H, Piersma A, et al. (2005) Endocrine disrupting and neurobehavioural effects of the brominated flame retardant TBBPA
in a reproduction study in rats. Reprod Toxicol 20(3):486-487.
4-106
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DOPO
VL = Very Low hazard L = Low hazard = Moderate hazard = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, , H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion by-
products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the table.
§ Based on analogy to experimental data for a structurally similar compound.
Chemical
CASRN
Human Health Effects
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ft
u
g
_u
'H
-*^
o
-------
DOPO
f
0
^,^^^
SMILES: O=Plc2ccccc2c3ccccc3Ol
CASRN: 35948-25-5
MW: 216.18
MF: C12H9O2P
Physical Forms:
Neat: Solid
Use: Flame retardant
Synonyms: DOP; DOPPO; 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide; 6H-dibenz[c,e][l,2]oxaphosphorin 6-oxide
Chemical Considerations: This is a discrete organic chemical with a MW below 1,000. EPI v 4. 1 1 was used to estimate physical/chemical and environmental fate
values in the absence of experimental data. Measured values from experimental studies were incorporated into the estimations. As described in the DfE Program
Alternatives Assessment Criteria for Hazard Evaluation, stable degradation products of the alternatives are evaluated. Therefore the hydrolysis product of DOPO was
evaluated in this assessment for endpoints typically obtained in the presence of water; based on a submitted guideline water solubility study reporting that 2-(2'-
hydroxyphenyl)phenyl phosphonic acid is readily formed by deesterification of DOPO in water. Although there were no separate experimental studies available for
the hydrolysis product, it was considered in the evaluation of the human health designations using structural alerts and professional judgment (ECHA, 2013).
Polymeric: No
Oligomeric: Not applicable
Metabolites, Degradates and Transformation Products: [2-(2'-Hydroxyphenyl)phenyl]phosphonic acid by hydrolytic deesterification (ECHA, 2013)
Analog: [2-(2'-Hydroxyphenyl)phenyl]phosphonic acid (the hydrolysis product of Analog Structure:
DOPO)
Endpoint(s) using analog values: Endpoints typically obtained in the presence f^"^
of water for [2-(2'-Hydroxyphenyl)phenyl]phosphonic acid, the hydrolysis L^
product of DOPO HO V
^iX
]
V°H
r°
Structural Alerts: Phosphinate esters - environmental toxicity (aquatic toxicity); Organophosphorus compounds - neurotoxicity; Phenols (for the hydrolysis product)
- neurotoxicity (EPA, 2010; EPA, 2012).
Risk Phrases: R43 - May cause sensitization by skin contact (ECHA, 2013).
Hazard and Risk Assessments: None located.
4-108
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
122
According to Organisation for Economic
Co-operation and Development (OECD)
102 (Measured)
117 (Measured)
359
(Extrapolated)
200 at 760 mmHg
pressure reported as 5 Torr (Measured)
>300 at 5 mmHg
(Estimated)
0.000022 at 25°C
(Extrapolated)
5 at 200°C
(Measured)
0.000012
(Estimated)
l.lxlO'8
for [2-(2'-hydroxyphenyl)phenyl]
phosphonic acid (Estimated)
Chang et al., 1998 (as cited in
ECHA, 2013)
Chernyshev et al., 1972
McEntee, 1987
International Resources, 2001
EPIv4.11;EPA, 1999
McEntee, 1987
International Resources, 2001
EPIv4.11
EPIv4.11
Adequate guideline study.
Consistent with other measured
values.
The boiling point at 760 mmHg was
extrapolated from the measured
boiling point at reduced pressure
using a computerized nomograph.
Value was obtained at a reduced
pressure, no further study details
reported.
Estimated value is greater than the
cutoff value, >300°C, according to
HPV assessment guidance.
The vapor pressure was extrapolated
from the measured boiling point at
reduced pressure using a
computerized nomograph.
Value reported at an elevated
temperature.
This value is applicable to the
hydrolysis product of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
4-109
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
Water Solubility (mg/L)
Log Kow
Flammability (Flash Point)
Explosivity
Pyrolysis
pH
DATA
3,574
at 25°C according to OECD 105 study.
DOPO is readily converted to [2-(2'-
hydroxyphenyl)phenyl] phosphonic acid
by deesterification in water; however, the
rate of hydrolysis and pH conditions were
not reported. (Measured)
460
(Estimated)
1.87
(Estimated)
1.33
for [2-(2'-hydroxyphenyl)phenyl]
phosphonic acid (Estimated)
Not readily combustible solid
EU Method A. 10 Flammability (Solids).
Fine powder sample melted to a clear
liquid and no ignition was observed.
(Measured)
Flash point: 222°C Cleveland open tester
(Measured)
Lower explosive limit: 980 g/m3
Considered non explosive. Vertical tube
test. (Measured)
Not applicable (Estimated)
REFERENCE
ECHA, 2013
EPIv4.11
EPIv4.11
EPIv4.11
ECHA, 2013
ECHA, 2013
ECHA, 2013
Professional judgment
DATA QUALITY
The reported water solubility is
measured for the hydrolysis product
of DOPO, in this guideline water
solubility study.
This compound hydrolyzes in
aqueous conditions.
This value is applicable to the
hydrolysis product of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
Guideline study reported in a
secondary source.
Nonguideline study reported in a
secondary source.
Nonguideline study reported in a
secondary source.
No data located.
The substance does not contain
functional groups that would be
expected to ionize; although this
compound hydrolyzes in aqueous
conditions.
4-110
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
pKa
Particle Size
DATA
Not applicable (Estimated)
REFERENCE
Professional judgment
DATA QUALITY
The substance does not contain
functional groups that would be
expected to ionize. Although this is
compound hydrolyzes in aqueous
conditions.
No data located.
HUMAN HEALTH EFFECTS
Toxicokinetics
Dermal Absorption in vitro
Absorption,
Distribution,
Metabolism &
Excretion
Oral, Dermal or Inhaled
Other
Acute Mammalian Toxicity
Acute Lethality
Oral
Dermal
Absorption of neat solid is expected to be negligible through skin. Absorption in solution is expected to be
moderate through skin, and moderate through lungs and gastrointestinal tract.
Absorption of neat solid negligible
through skin. Absorption in solution
moderate through skin. Absorption
moderate through lungs and GI tract.
(Estimated)
Professional judgment
No data located.
Estimated based on
physical/chemical properties
LOW: Based on experimental oral and dermal LD50 data in rats. No inhalation data were located.
Mouse (male) oral LD50 = 6,490 mg/kg,
Mouse (female) oral LD50 = 7,580 mg/kg
Rat oral LD50 > 2,000 mg/kg;
Observation period was 14 days. No
deaths occurred.
Rat dermal LD50 > 2,000 mg/kg
(semi-occlusive). Observation period was
14 days. No deaths occurred.
International Resources, 2001
ECHA, 2013
ECHA, 2013
Study details and test conditions
were not available.
Sufficient information in secondary
source. Study conducted in
accordance with OECD Guideline
40 1 and good laboratory practices
(GLP). Test substance was CASRN
35948-25-5 named Ukanol OOP 95
in study report. Primary reference
not identified; purity of test
substance not provided.
Sufficient information in secondary
source. Study conducted in
accordance with OECD guideline
402 and GLP. Test substance was
CASRN 35948-25-5 named HCA in
study report. Primary reference not
4-111
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
Inhalation
Carcinogenic!*
OncoLogic Results
Carcinogenicity (Rat and
Mouse)
Combined Chronic
Toxicity/Carcinogenicity
Other
Genotoxicity
Gene Mutation in vitro
Gene Mutation in vivo
DATA
REFERENCE
DATA QUALITY
identified. Neat test substance
(99.5% pure).
No data located.
MODERATE: OncoLogic estimates a low concern for carcinogenicity for the organophosphates chemical
class; However, there is uncertainty based on the lack of data and carcinogenic effects cannot be ruled out.
Low; although the structure of DOPO is
not fully represented by the phosphate and
phosphinate skeletons provided in the
program.
(Estimated)
OncoLogic, 2008
Estimated for the aryl phosphinate-
type compound.
No data located.
No data located.
No data located.
LOW: Experimental studies indicate that DOPO was not mutagenic to bacteria or mammalian cells and
did not cause chromosomal aberrations in vitro.
Negative in Ames assay; in Salmonella
typhimurium strains TA1535, TA97a,
TA98, TA100, and TA102 with and
without metabolic activation. Tested up to
5,024 (ig/plate (purity >99%). Positive
controls responded as expected.
Negative in Ames assay in Salmonella
typhimurium strains TA97, TA98, TA100,
and TA102 and Escherichia coli WP2 uvr
A pKM 101 with and without metabolic
activation. Tested up to 5,000 (ig/plate
(purity, industrial grade). Positive controls
responded as expected.
ECHA, 2013
Hachiya, 1987 (as cited in
ECHA, 2013)
Sufficient study details reported in a
secondary source. Study conducted
in accordance with OECD guideline
471 and GLP. Test substance was
CASRN 35948-25-5 named Ukanol
GK-F in study report. Primary
reference not identified.
Sufficient study details reported in a
secondary source. Not GLP study,
but adequate as supporting data.
No data located.
4-112
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
Chromosomal Aberrations in
vitro
Chromosomal Aberrations in
vivo
DNA Damage and Repair
Other
Reproductive Effects
Reproduction/Developmental
Toxicity Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Reproduction and Fertility
Effects
Other
Developmental Effects
Reproduction/
Developmental Toxicity
Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
DATA
Negative in Chinese hamster lung cells
with and without activation. Tested up to
216 (ig/mL (purity not provided). Positive
controls responded as expected.
REFERENCE
Ryu et al., 1994 (as cited in
ECHA, 2013)
DATA QUALITY
Sufficient study details reported in a
secondary source. Study equivalent
to OECD Guideline 473; not GLP
study.
No data located.
No data located.
No data located.
LOW: Based on closely related analogs with similar structures, functional groups, and physical/chemical
properties, as well as professional judgment.
Low potential for reproductive effects.
(Estimated by analogy)
Professional judgment
No data located.
No data located.
No data located.
Estimated based on analogy to a
structurally similar compound and
professional judgment.
MODERATE: There is uncertain concern for developmental neurotoxicity based on the potential for
cholinesterase (ChE) inhibition in dams that may result in alterations of fetal neurodevelopment. There is
an estimated Low potential for developmental effects based on closely related analogs with similar
structures, functional groups, and physical/chemical properties, as well as professional judgment.
There were no experimental data for the developmental or neurodevelopmental endpoints.
No data located.
No data located.
4-113
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
Prenatal Development
Postnatal Development
Prenatal and Postnatal
Development
Developmental Neurotoxicity
Other
Neurotoxicity
Neurotoxicity Screening
Battery (Adult)
Other
DATA
Uncertain concern for developmental
neurotoxicity based on the potential for
cholinesterase (ChE) inhibition in dams
that may result in alterations of fetal
neurodevelopment. (Estimated)
Low potential for developmental effects.
(Estimated by analogy)
REFERENCE
Professional judgment
Professional judgment
DATA QUALITY
No data located.
No data located.
No data located.
Estimated based on a structural alert
for organophosphates for the
neurotoxicity endpoint.
Estimated based on analogy to a
structurally similar compound and
professional judgment.
MODERATE: There is uncertain potential for neurotoxic effects based on a structural alert for
organophosphates. There is also uncertain potential for neurotoxic effects for the hydrolysis product of
DOPO [2-(2'-hydroxyphenyl)phenyl] phosphonic acid based on the phenols structural alert and
professional judgment.
Potential for neurotoxic effects based on a
structural alert for organophosphates.
(Estimated by analogy)
Potential for neurotoxic effects based on a
structural alert for phenols.
Estimated for the hydrolysis product of
DOPO, [2-(2'-hydroxyphenyl)phenyl]
phosphonic acid. (Estimated by analogy)
Professional judgment
Professional judgment
No data located.
Estimated based on a structural alert
for organophosphates and
professional judgment.
Estimated based on a structural alert
for phenols and professional
judgment for the hydrolysis product
of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
4-114
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
Repeated Dose Effects
Skin Sensitization
Skin Sensitization
DATA
REFERENCE
DATA QUALITY
LOW: Based on no significant effects on multiple endpoints in a 16-week dietary study in rats at doses up
to 1,094 mg/kg-day.
Male and female Wistar rats (20/sex/dose)
were fed diets containing 0, 0.24, 0.6, or
1.5%HCA ( 0, 159, 399, or 1,023 mg
HCA/kg-day to males; 0, 177, 445, or
1,094 mg HCA/kg-day to females) for 16
weeks (purity of test substance not
provided).
There were no significant effects on body
weight, food consumption, hematology,
limited clinical chemistry, urinalysis,
organ weight, and gross and microscopic
examination of major organs.
NOAEL= 1,023 mg/kg-day (males), 1,094
mg/kg-day (females); highest dose tested
LOAEL= Not established
ECHA, 2013
Sufficient information in secondary
source; data lacking regarding
detailed clinical observations and
neurobehavioral examination. Study
equivalent to OECD guideline 408.
Study pre-dates GLP. Test substance
identified as HCA in study report.
Primary reference not identified.
MODERATE: Limited data were available to categorize this compound; however, because an SI of 4.2 was
seen at a 5% concentration, this compound is considered to have a Moderate concern for skin Sensitization.
Because the test concentrations started a 5%, there is uncertainty as to if there would be skin Sensitization
at a concentration < 2% resulting in an SI of 3 which would warrant a High hazard designation.
Local lymph node assay conducted in
female CBA/J Rj mice. HCA tested at 5,
10, and 25% (w/v); four mice/treatment
group. Test substance >98% pure.
Significant lymphoproliferative response
was noted for HCA at concentrations of
10% (SI 4.4) and 5% (SI 4.2). SI for
positive control was 16.6. HCA was a
sensitizer under the conditions of the
study.
Risk phrase: R43: May cause Sensitization
by skin contact
ECHA, 2013
ECHA, 2013
Sufficient information in secondary
source. Study conducted in
accordance with OECD guideline
429 and GLP. Test substance was
CASRN 35948-25-5 named HCA in
study report. Primary reference not
identified.
Reported in a secondary source.
4-115
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
Respiratory Sensitization
[Respiratory Sensitization
Eye Irritation
Eye Irritation
Dermal Irritation
Dermal Irritation
Endocrine Activity
Immunotoxicity
Immune System Effects
DATA
REFERENCE
DATA QUALITY
No data located.
No data located.
MODERATE: Based on moderate signs of eye irritation in rabbits that cleared in 7 days.
Neat test material (0. 1 mL) was instilled
in left eye of 3 female albino rabbits. Eyes
were monitored for up to 7 days.
Moderate signs of eye irritation that
cleared in 7 days were observed among
the rabbits.
ECHA, 2013
Sufficient information in secondary
source. Study conducted in
accordance with OECD guideline
405 and GLP. Test substance was
CASRN 35948-25-5 named Ukanol
DOP in study report. Primary
reference not identified.
VERY LOW: Based on no skin reactions in semi-occlusive test in rabbits.
Not irritating. Neat test material (0.5 mL)
was applied in gauze patches to a clipped
skin area of 3 female albino rabbits;
patches were secured for 4 hours. Skin
was examined from 1 to 72 hours after
patch removal and skin washing. No skin
reactions were noted at any time point.
ECHA, 2013
Sufficient information in secondary
source. Study conducted in
accordance with OECD guideline
404 and GLP. Test substance was
CASRN 35948-25-5 named Ukanol
DOP in study report. Primary
reference not identified.
No data located.
No data located.
Estimated by professional judgment to have low potential for immunotoxic effects based on closely related
analogs with similar structures, functional groups, and physical/chemical properties.
Low potential for immunotoxic effects.
(Estimated by analogy)
Professional judgment
Estimated by analogy to a
structurally similar compound and
professional judgment.
4-116
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
ECOTOXICITY
ECOSAR Class
Phenols class; only the hydrolysis product [2-(2'-hydroxyphenyl)phenyl]phosphonic acid was assessed in
ECOSAR because DOPO hydrolyzes in water based on data from a water solubility study
Acute Aquatic Toxicity
LOW: Based on experimental acute aquatic toxicity values > 100 mg/L in fish, daphnia, and algae. DOPO
will hydrolyze in water; therefore only the hydrolysis product, [2-(2'-hydroxyphenyl)phenyl]phosphonic
acid, was assessed in ECOSAR, which is represented by the phenols class.
Fish LC50
Freshwater fish (Danio rerio) 96-hour
LC50 >100 mg/L;
96-hour NOEC = 100 mg/L;
The study was conducted under static
conditions.
(Experimental)
Oryzias latipes 48-hour LC50 = 370 mg/L
(95% CI, 280-500 mg/L)
Limit test conducted under static
conditions.
(Experimental)
96-hour LC50 = >100 mg/L
(Estimated)
ECOSAR: Phenols
Fish 96-hour LC50 = >100 mg/L
(Estimated)
ECOSAR: Neutral organics
ECHA, 2013
ECHA, 2013
ECOSAR v 1.11
ECOSAR v 1.11
4-117
Sufficient study details reported in a
secondary source. Study was
conducted in accordance with
OECD guideline 203. GLP
deviations were not considered
critical. Primary reference not
identified; test substance purity
>99%; Test substance
concentrations were kept within
20% of initial concentrations.
Test substance purity not reported;
sufficient study details reported in a
secondary source. The study follows
the methodology presented in the
Japanese Industrial Standard JIS K
0102-1986 No 71. Primary reference
not identified.
Estimation is for the hydrolysis
product; this compound hydrolyzes
in aqueous conditions.
Estimation is for the hydrolysis
product; this compound hydrolyzes
in aqueous conditions.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Daphnid LC50
Daphnia magna 48-hour EC50 >100
mg/L; 48-hour NOEC = 100 mg/L Limit
test conducted under static conditions.
Concentrations of test substance were
stable during study. Test substance purity
>99%.
(Experimental)
ECHA, 2013
Daphnia magna 48-hour EC50 = 240 mg/L Waaijers et al., 2013
(unbuffered);
no effect up to 289 mg/L when buffered to
pH7.5
Test conducted under static conditions.
Test substance purity =98%.
Concentrations of the test substance were
measured at the beginning and end of the
test.
(Experimental)
48-hour LC50 = 29 mg/L
(Estimated)
ECOSAR: Phenols
ECOSAR v 1.11
48-hour LC50 = >100 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSAR v 1.11
Sufficient study details reported in a
secondary source. Study was
conducted in accordance with
OECD guideline 202. GLP
deviations were not considered
critical. Primary reference not
identified.
Sufficient study details reported in a
primary source, Study was
conducted in accordance with
OECD Guideline 202 and GLP.
Estimation is for the hydrolysis
product; this compound hydrolyzes
in aqueous conditions.
Estimation is for the hydrolysis
product; this compound hydrolyzes
in aqueous conditions.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
4-118
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
Green Algae EC50
Chronic Aquatic Toxicity
Fish ChV
DATA
Green algae (Desmodesmus subspicatus)
72-hour ErC50 = 1 10 mg/L;
72-hour EbC50 = 100 mg/L;
EyC50 = 98 mg/L;
all nominal concentrations; concentrations
of test substance were stable during
study). EyC50 = biomass at the end of
exposure period minus biomass at the start
of the exposure period. Test substance
purity >99%.
(Experimental)
96-hour EC50 = >100 mg/L
(Estimated)
ECOSAR: Phenols
96-hour EC50 = >100 mg/L
(Estimated)
ECOSAR: Neutral organics
REFERENCE
ECHA, 2013
ECOSAR v 1.11
ECOSAR v 1.11
DATA QUALITY
Sufficient study details reported in a
secondary source. Study was
conducted in accordance with
OECD guideline 201 and GLP.
Primary reference not identified.
Estimation is for the hydrolysis
product; this compound hydrolyze s
in aqueous conditions.
Estimation is for the hydrolysis
product; this compound hydrolyze s
in aqueous conditions.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
MODERATE: Based on estimated chronic aquatic toxicity values for the primary degradation product [2-
(2'-hydroxyphenyl)phenyl]phosphonic acid of 5.6 mg/L for daphnid. DOPO will hydrolyze in water;
therefore only the hydrolysis product was assessed in ECOSAR, which is represented by the phenols class.
Fish ChV = 12 mg/L
(Estimated)
ECOSAR: Phenols
Fish ChV = 70 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSAR v 1.11
ECOSAR v 1.11
Estimation is for the hydrolysis
product; this compound hydrolyze s
in aqueous conditions.
Estimation is for the hydrolysis
product; This compound hydrolyzes
in aqueous conditions.
4-119
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Daphnid ChV
Daphnid ChV = 5.6 mg/L
(Estimated)
ECOSAR: Phenols
ECOSAR v 1.11
Daphnid ChV = 34 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSAR v 1.11
Estimation is for the hydrolysis
product; this compound hydrolyzes
in aqueous conditions.
Estimation is for the hydrolysis
product; this compound hydrolyzes
in aqueous conditions.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Green Algae ChV
Green algae ChV = 68 mg/L
(Estimated)
ECOSAR: Phenols
ECOSAR v 1.11
Green algae ChV = 54 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSAR v 1.11
4-120
Estimation is for the hydrolysis
product; this compound hydrolyzes
in aqueous conditions.
Estimation is for the hydrolysis
product; this compound hydrolyzes
in aqueous conditions.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
ENVIRONMENTAL FATE
Transport
Henry's Law Constant (atm-
m3/mole)
Sediment/Soil
Adsorption/Desorption - Koc
Under aqueous conditions, DOPO is expected to hydrolyze to [2-(2'-hydroxyphenyl)phenyl] phosphonic
acid based on data from a water solubility study. Therefore, the transport and mobility of DOPO and the
hydrolysis product of DOPO are evaluated. Level III fugacity models incorporating available physical and
chemical property data indicate that at steady state DOPO and [2-(2'-hydroxyphenyl)phenyl] phosphonic
acid are expected to be found primarily in soil and to a lesser extent, water. DOPO and [2-(2'-
hydroxyphenyl)phenyl] phosphonic acid are expected to be highly mobile in soil based on an experimental
KOC value; these compounds have the potential to migrate from soil into groundwater. The estimated
Henry's Law constant indicates that the hydrolysis product, [2-(2'-hydroxyphenyl)phenyl] phosphonic
acid will not significantly volatilize from water to the atmosphere. Volatilization from dry surfaces is also
not expected. In the atmosphere, DOPO is expected to exist in both the vapor and particulate phase, based
on its vapor pressure and [2-(2'-hydroxyphenyl)phenyl] phosphonic acid is expected to exist primarily in
the particulate phase. Vapor-phase DOPO is expected to have limited potential for photodegradation.
Particulates will be removed from air by wet or dry deposition.
<10'8 for [2-(2'-hydroxyphenyl)phenyl]
phosphonic acid (Estimated)
5.4 xlO'8
(Estimated)
36
According to OECD 121 (Measured)
120 (Estimated)
EPIv4.11
EPIv4.11
ECHA, 2013
EPIv4.11
This compound hydrolyzes in
aqueous conditions. This value is
applicable to the hydrolysis product
of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
Estimated by the HENRYWIN
Bond SAR model.
Adequate guideline study reported
in a secondary source. This study
was performed in acetonitrile and
water; it is unclear if this value is for
DOPO or the hydrolysis product
since DOPO is expected to
hydrolyze in water based on data
from a water solubility study.
This compound hydrolyzes in
aqueous conditions. This value is
4-121
-------
DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
applicable to the hydrolysis product
of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
Level III Fugacity Model
Air = 0.3%
Water =18.9%
Soil = 80.6%
Sediment = 0.1% (Estimated)
EPIv4.11
Air = 0%
Water =16%
Soil = 84%
Sediment = 0.2% (Estimated)
for [2-(2'-hydroxyphenyl)phenyl]
phosphonic acid
EPIv4.11
This compound hydrolyzes in
aqueous conditions. These values
are applicable to the hydrolysis
product of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
Persistence
HIGH: The persistence designation of DOPO is High considering ultimate degradation based on an
estimated environmental half-life of 75 days in soil. An intermediate, [2-(2'-hydroxyphenyl)phenyl]
phosphonic acid, is formed by hydrolysis of DOPO in aqueous environments. This primary degradation
product is expected to resist further environmental degradation based on an estimated half-life of 75 days
in soil. The rate of hydrolysis is expected to be dependent on pH, with increasing alkalinity resulting in
increasing rates of hydrolysis. A guideline OECD 301B Ready Biodegradability study indicated that
DOPO is not biodegradable under test conditions with activated sludge; however data from this protocol
are insufficient to determine a persistence designation. QSARs of aerobic and anaerobic biodegradation
estimate primary aerobic biodegradation in days-weeks and ultimate aerobic degradation in weeks-months
for both DOPO and the hydrolysis product. DOPO is not expected to undergo direct photolysis by sunlight
as it does not contain chromophores that absorb at wavelengths >290 nm. The atmospheric half-life for the
gas phase reactions of DOPO is estimated at 1.8 days, though it is not anticipated to partition significantly
to air.
Water
Aerobic Biodegradation
Passes Ready Test: No
Test method: OECD TG 30IB: CO2
Evolution Test
0% degradation after 28 days using an
activated sludge inoculum. (Measured)
Days-weeks (Primary Survey Model)
ECHA, 2013
EPIv4.11
Adequate guideline study reported
in a secondary source; this value is
expected to apply to both DOPO and
the hydrolysis product since DOPO
is expected to hydrolyze in water
based on data from a water
solubility study.
This compound hydrolyzes in
4-122
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DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
Soil
Air
Reactivity
Volatilization Half-life for
Model River
Volatilization Half-life for
Model Lake
Aerobic Biodegradation
Anaerobic Biodegradation
Soil Biodegradation with
Product Identification
Sediment/Water
Biodegradation
Atmospheric Half-life
Photolysis
Hydrolysis
DATA
Weeks-months (Ultimate Survey Model)
(Estimated)
>1 year (Estimated)
>1 year (Estimated)
Not probable (Anaerobic-methanogenic
biodegradation probability model)
1.8 days (Estimated)
Not a significant fate process (Estimated)
DOPO is readily converted to [2-(2'-
hydroxyphenyl)phenyl]phosphonic acid
by deesterification in water; however, the
rate of hydrolysis and pH conditions were
REFERENCE
EPIv4.11
EPIv4.11
EPIv4.11
EPIv4.11
Professional judgment; Mill,
2000
ECHA, 2013
DATA QUALITY
aqueous conditions. These values
are applicable to DOPO and for the
hydrolysis product of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
This compound hydrolyzes in
aqueous conditions. These values
are applicable to DOPO and for the
hydrolysis product of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
This compound hydrolyzes in
aqueous conditions. These values
are applicable to DOPO and for the
hydrolysis product of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
No data located.
No data located.
No data located.
The substance does not contain
functional groups that would be
expected to absorb light at
environmentally significant
wavelengths.
Summary statement reported in a
modified OECD 105 guideline water
solubility study; however, the rate of
hydrolysis and pH conditions was
4-123
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DOPO CASRN 35948-25-5
PROPERTY/ENDPOINT
Environmental Half-life
Bioaccumulation
Fish BCF
Other BCF
BAF
Metabolism in Fish
DATA
not reported. (Measured)
Phosphinate esters hydrolyze in water and
their rate of hydrolysis is correlated to pH;
increasing alkalinity results in increasing
rates of hydrolysis. (Estimated)
75 days (Estimated)
REFERENCE
EPA, 2010
PBT Profiler vl.301
DATA QUALITY
not reported.
Adequate summary statement from
guidance document.
Half-life estimated for the
predominant compartment (soil), as
determined by EPI methodology.
This value is applicable to DOPO
and for the hydrolysis product of
DOPO, for [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
LOW: The bioaccumulation hazard designation is based on the estimated BCF and BAF values that are
<100 for DOPO and the hydrolysis product of DOPO, [2-(2'-hydroxyphenyl)phenyl]phosphonic acid.
7.9 (Estimated)
3.5for[2-(2'-
hydroxyphenyl)phenyl]phosphonic acid
(Estimated)
7.7 (Estimated)
2.9 for [2-(2'-
hydroxyphenyl)phenyl]phosphonic acid
(Estimated)
EPIv4.11
EPIv4.11
EPIv4.11
EPIv4.11
This compound hydrolyzes in
aqueous conditions.
This value is applicable to the
hydrolysis product of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
No data located.
This compound hydrolyzes in
aqueous conditions.
This value is applicable to the
hydrolysis product of DOPO, [2-(2'-
hydroxyphenyl)phenyl] phosphonic
acid.
No data located.
ENVIRONMENTAL MONITORING AND BIOMONITORING
Environmental Monitoring
Ecological Biomonitoring
Human Biomonitoring
No data located.
No data located.
This chemical was not included in the NHANES biomonitoring report. (CDC, 2013).
4-124
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4-125
-------
CDC (2013) Fourth national report on human exposure to environmental chemicals, updated tables, March 2013.
http://www.cdc.gov/exposurereport/pdf/FourthReport_UpdatedTables_Mar2013.pdf.
Chang TC, Wu KH, Wu TR, et al. (1998) Thermogravimetric analysis study of a cyclic organo-phosphorus compound. Phosphorus Sulfur Silicon
139:45-56.
Chernyshev EA and et al. (1972) J Gen Chem USSR 42:88-91.
ECHA (2013) 6H-dibenz[c,e][l,2]oxaphosphorin 6-oxide. Registered substances. European Chemicals Agency.
http://apps.echa.europa.eu/registered/data/dossiers/DISS-db99cfP9-92de-Odla-e044-00144f67d031/DISS-db99cff9-92de-Odla-e044-
00144f67d031_DISS-db99cff9-92de-Odla-e044-00144f67d031.html.
ECOSAR Ecological Structure Activity Relationship (ECOSAR). Estimation Programs Interface (EPI) Suite for Windows, Version 1.11.
Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency, http://www.epa.gov/oppt/newchems/tools/21ecosar.htm.
EPA (1999) Determining the adequacy of existing data. High Production Volume (HPV) Challenge. Washington, DC: U.S. Environmental
Protection Agency, http://www.epa.gov/hpv/pubs/general/datadeqfn.pdf
EPA (2010) TSCA new chemicals program (NCP) chemical categories. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/newchems/pubs/npcchemicalcategories.pdf
EPA (2012) Using noncancer screening within the SF initiative. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/sf/pubs/noncan-screen.htm.
EPI Estimation Programs Interface (EPI) Suite, Version 4.11. Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency.
http://www.epa.gov/opptintr/exposure/pubs/episuitedl.htm.
HachiyaN (1987) Evaluation of chemical genotoxicity by a series of short term tests. Akita Igaku 14(2):269-292.
International Resources (2001) OPC/OPC super clean grade. MSDS: Material safety data sheet, http://www.iri-us.com/msds/clean.html.
McEntee TE (1987) PC-Nomograph — Programs to enhance PC-GEMS estimates of physical properties for organic chemicals. Version 2.0 -
EGA/CGA. MSDOS: 12/4/87. The Mitre Corporation.
Mill T (2000) Photoreactions in surface waters. In: Boethling R, Mackay D, eds. Handbook of Property Estimation Methods for Chemicals,
Environmental Health Sciences. Boca Raton: Lewis Publishers.:355-381.
OncoLogic (2008) Version 7.0. U.S. Environmental Protection Agency and LogiChem, Inc.
4-126
-------
PBT Profiler Persistent (P), Bioaccumulative (B), and Toxic (T) Chemical (PBT) Profiler, Version 1.301. Washington, DC: U.S. Environmental
Protection Agency, www.pbtprofiler.net.
Ryu JC, Lee S, Kim KR, et al. (1994) Evaluation of the genetic toxicity of synthetic chemicals (I). Chromosomal aberration test on Chinese
hamster lung cells in vitro. Environ Mutagens Carcinogens 14(2): 138-144.
Waaijers SL, Hartmann J, Soeter AM, et al. (2013) Toxicity of new generation flame retardants to Daphnia magna. Sci Total Environ 463-
464:1042-1048.
4-127
-------
Fyrol PMP
VL = Very Low hazard L = Low hazard = Moderate hazard H = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion
by-products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the
table.
Based on analogy to experimental data for a structurally similar compound.; The highest hazard designation of any of the oligomers with MW <1,000.
Chemical
CASRN
Human Health Effects
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4-128
-------
Fyrol PMP
Representative Structure
CASRN: 63747-58-0
MW: > 1,000; with a significant
percentage of components
having MW<1,000
MF: (C13H1303P C6H602)X
Physical Forms: Solid
Neat: Solid
Use: Flame retardant
SMILES: cl(OP(C)(=O)Oc2cc(O)ccc2)cc(OP(C)(=O)Oc2ccccc2)cccl (n=l);
c 1 (OP(C)(=O)Oc4cc(OP(C)(=O)Oc3cc(O)ccc3)ccc4)cc(OP(C)(=O)Oc2ccccc2)ccc 1 (n=2);
c 1 (OP(C)(=O)Oc5cc(OP(C)(=O)Oc3cc(OP(C)(=O)Oc4cc(O)ccc4)ccc3)ccc5)cc(OP(C)(=O)Oc2ccccc2)ccc 1 (n=3);
c 1 (OP(C)(=O)Oc6cc(OP(C)(=O)Oc3cc(OP(C)(=O)Oc4cc(OP(C)(=O)Oc5cc(O)ccc5)ccc4)ccc3)ccc6)cc(OP(C)(=O)Oc2ccccc2)ccc 1 (n=4)
Synonyms: Phosphonic acid, P-methyl-, diphenyl ester, polymer with 1,3-benzenediol; Phosphonic acid, methyl-, diphenyl ester, polymer with 1,3-benzenediol; 1,3-
Benzenediol, polymer with diphenyl methylphosphonate; Diphenyl methylphosphonate-resorcinol copolymer; Aryl alkylphosphonate; Poly(m-phenylene
methylphosphonate)
Trade Name: Fyrolflex PMP
CASRN 124933-95-5 was identified by literature searches based on name as a related alternative. CASRN 124933-95-5 has a slightly different structure, and no other
applicable data were found for this CASRN.
Chemical Considerations: This alternative is a polymer consisting of oligomers with MWs above and below 1,000 daltons according to commercial product
datasheets.
The oligomers with a MW > 1,000, where n>5, are assessed using the available polymer assessment literature.
The components with a MW < 1,000 are evaluated with four representative structures, where n=l, 2, 3 and 4, as indicated in the SMILES entry. The low MW
components are assessed with EPI v4.11 and ECOSARvl.ll estimates due to an absence of publicly available experimental physical/chemical, environmental fate
and aquatic toxicity values. A typical phosphorus content of 17.5% was reported from the commercial product literature. (Hsu, 2013; ICL, 2013).
Polymeric: Yes
Oligomeric: This polymer is terminated with either resorcinol and/or phenyl groups based on the starting materials. The repeating units of this polymer are m-
phenylene methylphosphonate. A representative structure for n=l is identified in the SMILES section above.
Metabolites, Degradates and Transformation Products: None identified. Environmental degradation of Fyrol PMP has not been demonstrated in experimental
studies. Degradation of Fyrol PMP by sequential dephosphorylation could produce phosphinates, phenol (CASRN 108-95-2) or resorcinol (CASRN 108-46-3). The
importance of dephosphorylation relative to possible competing pathways has not been demonstrated in a published study. (Professional judgment)
Analog: Resorcinol bis-diphenylphosphate (RDP; CASRN 125997-21-9); tricresyl
phosphate (TCP; CASRN 1330-78-5);and confidential analogs
Endpoint(s) using analog values: Carcinogenicity, genotoxicity, reproductive,
Analog Structure:
4-129
-------
developmental, repeated dose
n=l-7
Resorcinol bis-diphenylphosphate (RDP; CASRN 125997-21-9}
\
Phosphoric acid, tris(methylphenyl) ester
(CDP; CASRN 1330-78-5)
Representative structure
Structural Alerts: Phenols - neurotoxicity; Organophosphorus compounds - neurotoxicity. (EPA, 2012).
Risk Phrases: Not classified by Annex VI Regulation (EC) No 1272/2008 (ESIS, 2012).
Hazard and Risk Assessments: None located.
4-130
-------
Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
Water Solubility (mg/L)
52 (Measured)
>300
(Estimated)
<10"8 for n= 1-4 (Estimated)
<10'8 (Estimated)
8.4
forn=l (Estimated)
0.1
for n=2 (Estimated)
0.001
for n=3 (Estimated)
l.SxlO'5
for n=4 (Estimated)
<0.001
for the n>5 oligomers (Estimated)
<0.01% (Measured)
ICL, 2010
EPA, 1999;EPIv4.11
EPA, 1999;EPIv4.11
Boethling and Nabholz, 1997;
Professional judgment
EPIv4.11
EPIv4.11
EPIv4.11
EPIv4.11;EPA, 1999
Boethling and Nabholz, 1997;
Professional judgment
ICL, 2010
Reported in a material safety
datasheet.
Estimate based on four
representative structures with MW
< 1,000. Also estimated for
oligomers with MWs > 1,000. Cutoff
value according to HPV assessment
guidance and cutoff value used for
large, high MW solids.
Estimates based on the
representative structures with MW
< 1,000. Cutoff value for nonvolatile
compounds according to HPV
assessment guidance.
Cutoff value for large, high MW
polymer components.
Estimates based on representative
oligomer where n=l .
Estimates based on representative
oligomer where n=2.
Estimates based on representative
oligomer where n=3 .
Estimates based on representative
oligomer where n=4. Values are less
than the cutoff value, <0.001 mg/L,
for non-soluble compounds
according to HPV assessment
guidance.
Cutoff value for large, high MW
non-ionic polymer components.
Reported in a material safety
datasheet.
4-131
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Log Kow
Flammability (Flash Point)
Explosivity
Pyrolysis
pH
pKa
Particle Size
DATA
3.4
forn=l (Estimated)
4.4
for n=2 (Estimated)
5.3
for n=3 (Estimated)
6.3
for n=4 (Estimated)
Not flammable (Measured)
Not expected to form explosive mixtures
with air. (Estimated)
REFERENCE
EPIv4.11
EPIv4.11
EPIv4.11
EPIv4.11
ICL, 2010
Professional judgment
DATA QUALITY
Estimates based on representative
oligomer where n=l .
Estimates based on representative
oligomer where n=2.
Estimates based on representative
oligomer where n=3 .
Estimates based on representative
oligomer where n=4.
Reported in safety datasheet and
based on its use as a flame retardant.
No experimental data located; based
on its use as a flame retardant.
No data located.
No data located.
No data located.
No data located.
HUMAN HEALTH EFFECTS
Toxicokinetics
Dermal Absorption
Absorption,
Distribution,
Metabolism &
Excretion
in vitro
Oral, Dermal or Inhaled
Other
Acute Mammalian Toxicity
Acute Lethality
Oral
Dermal
No experimental data were located. Based on professional judgment, absorption is expected to be poor by
all routes for the low MW (<1,000) fraction. There is no absorption expected for any route of exposure for
the MW >1,000 components.
Absorption is expected to be negligible by
all routes for the neat material and poor
by all routes for the low MW fraction if in
solution.
Professional judgment
Estimated based on professional
judgment.
No data located.
LOW: Experimental data indicates that the LD50 are >2,000 mg/kg when administered orally and
dermally to rats. Experimental data for the analog, phosphoric trichloride, polymer with 1,3-benzenediol,
phenyl ester (CASRN 125997-21-9) indicates an LC50 > 4.14 mg/L.
Rat LD50 >2,000 mg/kg in a 75% DMSO
solution
Rabbit LD50 >5,000 mg/kg
ICL, 2010
ICL, 2010
Reported in a material safety
datasheet with limited study details.
Reported in a material safety
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Inhalation
Carcinogenicity
OncoLogic Results
Carcinogenicity (Rat and
Mouse)
Combined Chronic
Toxicity/Carcinogenicity
DATA
Rat inhalation LC50 > 4.14 mg/L
REFERENCE
EPA, 2010
DATA QUALITY
datasheet with limited study details.
Estimated by analogy to Phosphoric
trichloride, polymer with 1,3-
benzenediol, phenyl ester (CASRN
125997-21-9)
LOW: Estimated based on analogy to tricresyl phosphate (TCP). There was no evidence of Carcinogenicity
in rats or mice following dietary exposure to a commercial mixture of TCP for 2 years. There were no
experimental data located for this substance.
2-Year dietary study in Fischer 344/N rats
(95/sex/concentration)
Test substance concentrations: 0, 75, 150,
300 ppm (approximately 0, 3, 6, and 13
mg/kg bw-day for males and 0, 4, 7, and
15 mg/kg bw-day for females)
Chronic toxicity: NOAEL =13 mg/kg
bw-day (males); 4 mg/kg bw-day for
females
LOAEL = 26 mg/kg bw-day (males) and
7 mg/kg bw-day (females) for
cytoplasmic vacuolization of adrenal
cortex
No evidence of carcinogenic activity
(Estimated by analogy)
2-Year dietary study in B6C3F1 mice
(95/sex/concentration)
Test substance concentrations: 0, 60, 125,
250 ppm (approximately 0, 7, 13, and 27
mg/kg bw-day for males and 0, 8, 18, and
37 mg/kg bw-day for females)
NTP, 1994
NTP, 1994
This polymer is not amenable to
available estimation methods.
No data located.
Estimated based on analogy to
tricresyl phosphate (TCP); study
details reported in a reliable primary
source; test substance: Tricresyl
phosphate (CASRN 1330-78-5) as a
commercial product comprised of
18% dicresyl phosphate esters
(unconfirmed isomeric composition)
and 79% tricresyl phosphate esters
(21% confirmed as tri-m-cresyl
phosphate, 4% as tri-p-cresyl
phosphate, and no detectable tri-o-
cresyl phosphate [<0.1%]).
Estimated based on analogy to
tricresyl phosphate (TCP); study
details reported in a reliable primary
source; test substance: Tricresyl
phosphate (CASRN 1330-78-5) as a
commercial product comprised of
4-133
-------
Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Other
Genotoxicity
Gene Mutation in vitro
Gene Mutation in vivo
DATA
chronic toxicity NOAEL =18 mg/kg bw-
day for females, not established for males
LOAEL: 7 mg/kg bw-day (males) and 37
mg/kg bw-day (females) for ceroid
pigmentation of adrenal cortex
No evidence of carcinogenic activity
(Estimated by analogy)
REFERENCE
DATA QUALITY
18% dicresyl phosphate esters
(unconfirmed isomeric composition)
and 79% tricresyl phosphate esters
(21% confirmed as tri-m-cresyl
phosphate, 4% as tri-p-cresyl
phosphate, and no detectable tri-o-
cresyl phosphate [<0.1%]).
No data located.
LOW: Based on results from an Ames assay, analogy to RDP (CASRN 125997-21-9) and professional
judgment. The test substance was reported to be negative for gene mutations in an Ames assay; however,
there were no experimental chromosomal aberrations data for the test substance. The analog RDP did not
cause gene mutations or chromosomal aberrations in vitro and did not produce an increase in micronuclei
in mice in vivo.
Negative, Ames assay
Negative in Salmonella typhimurium
(strains not indicated) with and without
metabolic activation at concentrations up
to 5,000 (ig/plate.
No cytotoxicity was evident.
(Estimated by analogy)
Negative in Escherichia coll (strains not
indicated) with and without metabolic
activation at concentrations up to 5,000
(ig/plate.
No cytotoxicity was evident.
(Estimated by analogy)
ICL, 2010
EPA, 2010; Pakalin et al., 2007
EPA, 2010; Pakalin et al., 2007
Reported in a material safety
datasheet with limited study details.
Estimated based on analogy.
Guideline study. Data are for a
commercial polymeric mixture of
the analog RDP (CASRN 125997-
21-9).
Estimated based on analogy.
Guideline study. Data are for a
commercial polymeric mixture of
the analog RDP (CASRN 125997-
21-9).
No data located.
4-134
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Chromosomal Aberrations in
vitro
Chromosomal Aberrations in
vivo
DNA Damage and Repair
Other
Reproductive Effects
Reproduction/Developmental
Toxicity Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
DATA
Negative in chromosomal aberration test
(cultured human lymphocytes) with and
without metabolic activation at
concentrations up to 625 (ig/mL.
Cytotoxicity data not indicated.
(Estimated by analogy)
Negative in mammalian erythrocyte
micronucleus test (Swiss mice) following
a single oral dose of 5,000 mg/kg-bw.
(Estimated by analogy)
Negative in mammalian erythrocyte
micronucleus test (mice) following single
oral dose of 500 mg/kg-bw.
(Estimated by analogy)
Limited bioavailability expected for the
high MW (>1,000) components.
(Estimated for n >5 oligomers)
REFERENCE
EPA, 2010; Pakalin et al., 2007
EPA, 2010; Pakalin et al., 2007
Submitted confidential study
Boethling and Nabholz, 1997;
Professional judgment
DATA QUALITY
Estimated based on analogy.
Guideline study. Data are for a
commercial polymeric mixture of
the analog RDP (CASRN 125997-
21-9).
Estimated based on analogy.
Guideline study. Data are for a
commercial polymeric mixture of
the analog RDP (CASRN 125997-
21-9).
Estimated based on analogy.
Reported in a submitted confidential
study for the analog RDP (CASRN
125997-21-9) conducted in
accordance with GLP and OECD
Guideline 474.
No data located.
Based on polymer assessment
literature.
MODERATE: Based on data for a confidential analog and professional judgment. There were no
experimental data located for the substance Fyrol PMP. There is potential for reproductive toxicity based
on data for a confidential analog reporting reduced litter size and weight at 250 mg/kg-day (NOAEL: 50
mg/kg-day ) a An experimental study for the analog RDP indicated no adverse effects on reproductive
performance or fertility parameters at doses up to 1,000 mg/kg-day (highest dose tested) in a two
generation dietary study in parental rats. Developmental changes effecting the reproductive system were
also reported in F1 female rats at 250 mg/kg-day. In the absence of experimental data for this substance,
and conflicting results for analogs, a conservative approach was used to assign a Moderate hazard
designation.
Two generation dietary reproduction
study in rats. Sprague-Dawley rats
(30/sex/dose) were fed 0, 50, 500, or
EPA, 2010; Pakalin et al., 2007
No data located.
Estimated based on analogy.
Guideline study. Data are for a
commercial polymeric mixture of
4-135
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Screen
1,000 mg/kg-day to the analog RDP in the
diet for 10 weeks.
There were no reproductive or systemic
effects reported in parental rats at doses
as high as 1,000 mg/kg-day.
Developmental changes affecting the
reproductive system (delayed vaginal
opening and preputial separation) were
reported in FI female rats at 500 and
1,000 mg/kg-day. This effect was
considered by study authors to be
secondary to reduction of body weight in
I generation during week 1 (treated
animals had decreased body weights
compared to controls during week 1,
reportedly due to an initial aversion to
taste of diet)
Parental systemic and reproductive
toxicity:
NOAEL: > 1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
Offspring (developmental) reproductive
toxicity:
NOAEL(Figeneration): 50 mg/kg-day
LOAEL (Figeneration): 500 mg/kg-day
(for vaginal opening and preputial
separation)
(Estimated by analogy)
the analog RDP (CASRN 125997-
21-9).
4-136
-------
Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Reproduction and Fertility
Effects
Other
Developmental Effects
Reproduction/
Developmental Toxicity
Screen
DATA
Potential for reproductive toxicity; no
pregnancies (1,000 mg/kg-day); reduced
litter size and weight (250 mg/kg-day).
NOAEL: 50 mg/kg-day
LOAEL: 250 mg/kg-day
(Estimated by analogy)
Limited bioavailability expected.
(Estimated for n >5 oligomers)
REFERENCE
Professional judgment;
Submitted confidential study
Boethling and Nabholz, 1997;
Professional judgment
DATA QUALITY
Estimated by analogy to confidential
analog.
Based on cutoff value for large, high
MW non-ionic polymers.
MODERATE: Based on analogy to RDP (CASRN 125997-21-9) and professional judgment. There were no
experimental data for the substance Fyrol PMP. An experimental study for the analog RDP reported a
NOAEL of 50 mg/kg-day in a two generation dietary reproduction study in rats. Adverse effects included
delayed vaginal opening and preputial separation at a dose of 500 mg/kg-day. Though the changes are
considered by the study authors to be secondary to reduced body weight in the Ft generation, reported
data were insufficient to determine if this was a secondary effect. No adverse developmental effects were
observed in rabbits following oral administration of the analog RDP at doses up to 1,000 mg/kg-day.
There were no data located for the developmental neurotoxicity endpoint. The analog RDP (CASRN
125997-21-9) has been shown to cause cholinesterase inhibition which may be an indicator of potential
developmental neurotoxicity.
No data located.
4-137
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Two generation dietary reproduction
study in rats. Sprague-Dawley rats
(30/sex/dose) were fed 0, 50, 500, or
1,000 mg/kg-day to the analog RDP in the
diet for 10 weeks.
Vaginal opening and preputial separation
were delayed at 500 and 1,000 mg/kg-
day. This effect was considered by study
authors to be secondary to reduction of
body weight in FI generation during week
1 (treated animals had decreased body
weights compared to controls during
week 1, reportedly due to an initial
aversion to taste of diet).
NOAEL(Figeneration): 50 mg/kg-day
LOAEL (Figeneration): 500 mg/kg-day
(for vaginal opening and preputial
separation)
(Estimated by analogy)
EPA, 2010; Pakalin et al., 2007
Estimated based on analogy.
Guideline study. Data are for a
commercial polymeric mixture of
the analog RDP (CASRN 125997-
21-9); limited study details reported
to determine if the developmental
effect is secondary to reduced body
weight in Fl rats.
4-138
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Prenatal Development
Postnatal Development
Prenatal and Postnatal
Development
Developmental Neurotoxicity
Other
DATA
Pregnant rabbits; oral gavage; gestation
days (GDs) 6-28; 0, 50, 200 or 1,000
mg/kg-day test material containing the
analog RDP
No clinical signs of toxicity. No adverse
effects on maternal food consumption,
body weight gain or organ weights. No
adverse effects on fetal body weights,
viability, or any developmental endpoint
measured.
NOAEL (maternal and developmental
toxicity): >1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
(Estimated by analogy)
There were no data located for the
developmental neurotoxicity endpoint. As
a result, there is uncertain potential for
developmental neurotoxicity for this
substance. The analog RDP (CASRN
125997-21-9) has been shown to cause
cholinesterase inhibition which may be an
indicator of potential developmental
neurotoxicity.
(Estimated)
Limited bioavailability expected.
(Estimated for n>5 oligomers)
REFERENCE
EPA, 2010; Environment
Agency, 2009
Professional judgment
Boethling and Nabholz, 1997;
Professional judgment
DATA QUALITY
Estimated based on analogy.
Guideline study reported in a
secondary source. Data are for a
commercial polymeric mixture of
the analog RDP (CASRN 125997-
21-9).
No data located.
No data located.
Estimated by analogy to RDP
(CASRN 125997-21-9).
Based on cutoff value for large, high
MW non-ionic polymers.
4-139
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Neurotoxicity
MODERATE: Based on data for the analog RDP (CASRN 125997-21-9) and professional judgment. There
were no experimental data for the substance Fyrol PMP. A study for the analog RDP reported a 28-day
inhalation LOAEL of 0.5 mg/L for inhibition of plasma ChE in rats (NOAEL = 0.1 mg/L). The
neurotoxicity criteria values are tripled for 28-day studies to correlate to the criteria values based on 90-
day repeated dose studies; the LOAEL and NOAEL of 0.5 mg/kg-day and 0.1 mg/kg-day, respectively, lie
within the MODERATE hazard range from 0.06 - 0.6 mg/L. There is also potential for neurotoxicity based
on the presence of the phenol and organophosphorus structural alerts.
Neurotoxicity Screening
Battery (Adult)
Other
2 8-day inhalation study in rats with the
analog RDP (CASRN 125997-21-9); 0,
0.1, 0.5 and 2.0 mg/L (aerosol)
Significant inhibition of plasma
cholinesterase (ChE) (0.5 and 2.0 mg/L).
No clinical signs suggestive of neurotoxic
effect. ChE was not affected after study
termination.
NOAEL: 0.1 mg/L
LOAEL: 0.5 mg/L (plasma ChE
inhibition)
(Estimated by analogy)
28-day oral (gavage) study in mice with
the analog RDP (CASRN 125997-21-9);
0, 500, 1,500, 5,000 mg/kg-day.
Dose-related decrease in plasma ChE
compared to controls, which was no
longer apparent after the 60 day recovery
period.
No NOAEL/LOAEL determined.
(Estimated by analogy)
Limited bioavailability expected.
(Estimated for n>5 oligomers)
Potential for neurotoxic effects based on a
Environment Agency, 2009
Environment Agency, 2009
Boethling and Nabholz, 1997;
Professional judgment
EPA, 2012; Professional
Estimated based on analogy to RDP
(CASRN 125997-21-9). Study
details reported in a secondary
source; study was not designed to
assess all neurological parameters;
criteria values are tripled for
chemicals evaluated in 28-day
studies; the LOAEL of 0.5 mg/kg-
day falls within the Moderate hazard
criteria (0.06-0.6 mg/L).
Estimated based on analogy. Study
details reported in a secondary
source; study was not designed to
assess all neurological parameters;
cannot rule out all neurotoxicity.
Based on cutoff value for large, high
MW non-ionic polymers.
Estimated based on a structural alert
4-140
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
structural alert for phenol and
organophosphorus compounds.
judgment
for phenols and organophosphorus
compounds and professional
judgment.
Repeated Dose Effects
MODERATE: Based on analogy to RDP (CASRN 125997-21-9), a confidential analog and professional
judgment. There were no experimental data for the test substance Fyrol PMP. A 4-week inhalation
exposure study in rats to 0.5 mg/L of the analog RDP as an aerosol resulted in alveolar histiocytosis
(NOAEC = 0.1 mg/L- day). No other exposure-related gross or microscopic pathology was identified in any
organ in this study. The repeated dose criteria values are tripled for 28-day studies to correlate to the
criteria values based on 90-day repeated dose studies; this study lies in the MODERATE hazard range
from 0.06 - 0.6 mg/L. There is also potential for liver toxicity based on a confidential analog (NOEL = 300
mg/kg-day).
4-141
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Immune System Effects
DATA
In a 4-week inhalation study Sprague-
Dawley rats (10/sex/group) were exposed
(aerosol, nose only) to 0, 100, 500 or
2,000 mg/m3 (0, 0.1, 0.5, or 2 mg/L) of
the analog RDP.
No deaths or clinical signs of toxicity.
Decreased body weight and food
consumption in males. Significant
inhibition of plasma cholinesterase in
females at 500 and 2,000 mg/m3 and in
males at 2,000 mg/m3. White foci in the
lungs at 2,000 mg/m3 and alveolar
histiocytosis at 500 and 2,000 mg/m3.
Although lung changes are relevant, they
were not considered to be a reflection of a
specific toxic response to the analog
RDP; these changes are characteristic of
exposure to non-cytotoxic water-insoluble
materials.
No other gross or microscopic pathology
in any organ.
NOAEC: 100 mg/m3 (0.1 mg/L)
LOAEC: 500 mg/m3 (0.5 mg/L; based on
alveolar histiocytosis)
(Estimated based on analogy)
28-day oral study, rats
Potential for liver toxicity.
NOEL: 300 mg/kg-day
(Estimated based on analogy)
Limited bioavailability expected for the
high MW (>1,000) components.
(Estimated for n >5 oligomers)
Negative, oral gavage study in mice.
REFERENCE
EPA, 2010; Environment
Agency, 2009
Submitted confidential study;
Professional judgment
Boethling and Nabholz, 1997;
Professional judgment
EPA, 2010
DATA QUALITY
Estimated based on analogy.
Guideline study reported in a
secondary source. Data are for a
commercial polymeric mixture of
the analog RDP (CASRN 125997-
21-9).
Estimated based on analogy to
confidential analog.
Based on polymer assessment
literature.
Estimated based on analogy.
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Skin Sensitization
Skin Sensitization
Respiratory Sensitization
[Respiratory Sensitization
Eye Irritation
Eye Irritation
DATA
Female B6C3F1 mice (50/group) were
exposed via oral gavage to 0, 500, 1,500,
or 5,000 mg/kg-day of the analog RDP
for 28 days.
No deaths, clinical signs of toxicity, or
effects on body or organ weights. No
adverse histopathological changes or
necropsy findings. No treatment-related
changes in peritoneal cell numbers or cell
types, peritoneal macrophage phagocytic
activity or host susceptibility to infection.
No adverse effect on splenic natural killer
cell activity, lymphocyte blastogenesis, or
antibody-forming cell function. There
were significant decreases in erythrocyte
cholinesterase activity and plasma
pseudocholinesterase activity in all dose
groups, but both enzyme activities
returned to control levels at the end of the
60 day recovery period.
REFERENCE
DATA QUALITY
Guideline study reported in a
secondary source. Data are for a
commercial polymeric mixture of
the analog RDP (CASRN 125997-
21-9).
LOW: Negative for skin Sensitization in guinea pigs.
Non-sensitizing, guinea pigs
Not a sensitizer, Modified Buehler
Method
Submitted confidential study
ICL, 2010
Adequate confidential study
Reported in a material safety
datasheet with limited study details.
No data located.
No data located.
LOW: Fyrol PMP was mildly irritating to rabbit eyes.
Mild, rabbits
Negative, rabbits
ICL, 2010
Submitted confidential study
Reported in a material safety
datasheet with limited study details.
Study details and test conditions
were not available.
4-143
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Dermal Irritation
Dermal Irritation
Endocrine Activity
DATA
REFERENCE
DATA QUALITY
LOW: Fyrol PMP was mildly irritating to rabbit skin.
Mild irritant, rabbit
ICL, 2010
Reported in a material safety
datasheet with limited study details.
No experimental data were located to evaluate and determine if Fyrol PMP affects endocrine activity.
However, resorcinol, a metabolite of the analog RDP (CASRN 125997-21-9) and a starting material in
Fyrol PMP synthesis, is listed as a suspected endocrine disruptor by the EU.
Resorcinol (CASRN 108-46-3) is listed as
a potential endocrine disruptor on the EU
Priority List of Suspected Endocrine
Disrupters.
(Estimated by analogy)
European Commission, 2012
Estimated by analogy. "Potential for
endocrine disruption. In vitro data
indicating potential for endocrine
disruption in intact organisms. Also
included effects in-vivo that may, or
may not, be endocrine disruption-
mediated. May include structural
analyses and metabolic
considerations".
4-144
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Immunotoxicity
Immune System Effects
DATA
REFERENCE
DATA QUALITY
The analog, RDP (CASRN 125997-21-9), had no effect on immunological parameters at doses up to 5,000
mg/kg-day (highest dose tested) in an oral gavage study in mice. The higher MW components of this
polymer (MW >1,000) are expected to have limited bioavailability and have low potential for
immunotoxicity.
Negative, oral gavage study in mice.
Female B6C3F1 mice (50/group) were
exposed via oral gavage to 0, 500, 1,500,
or 5,000 mg/kg-day for the analog RDP
for 28 days.
No deaths, clinical signs of toxicity, or
effects on body or organ weights. No
adverse histopathological changes or
necropsy findings. No treatment-related
changes in peritoneal cell numbers or cell
types, peritoneal macrophage phagocytic
activity or host susceptibility to infection.
No adverse effect on splenic natural killer
cell activity, lymphocyte blastogenesis, or
antibody-forming cell function. There
were significant decreases in erythrocyte
cholinesterase activity and plasma
pseudocholinesterase activity in all dose
groups, but both enzyme activities
returned to control levels at the end of the
60 day recovery period.
Limited bioavailability expected for the
high MW (>1,000) components.
(Estimated for n >5 oligomers)
EPA, 2010
Boethling and Nabholz, 1997;
Professional judgment
Estimated based on analogy.
Guideline study reported in a
secondary source. Data are for the
analog, a commercial polymeric
mixture of RDP (CASRN 125997-
21-9).
Based on polymer assessment
literature.
4-145
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
ECOTOXICITY
ECOSAR Class
Phenols
Acute Aquatic Toxicity
HIGH: Based on estimated acute aquatic toxicity values for fish, daphnia, and green algae using the
phenols SAR for a representative structure, where n=l, with a MW <1,000. The high MW components,
with a MW>1,000 have low water solubility and are expected to have no effects at saturation (NES).
Fish LC50
Freshwater fish 96-hour LC50:
6.2 mg/L (ECOSAR class: Phenols)
Freshwater fish 96-hour LC50:
n=2: 1.6 mg/L
n=3: 0.39 mg/L
n=4: 0.09 mg/L
(ECOSAR class: Phenols)
(Estimated)
NES
(Estimated)
ECOSAR v 1.11
ECOSAR v 1.11
Professional judgment
Estimate based on representative
oligomer n=l.
Estimates based on representative
oligomers n=2 through n=4. The
corresponding estimated effects
exceed the water solubilities (0.1
mg/L for n=2, 0.001 mg/L for n=3,
and 0.00001 mg/L for n=4) by more
than lOx. NES are predicted for
these endpoints.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Daphnid LC50
Daphnia magna 48-hour LC50:
3.5 mg/L (ECOSAR class: Phenols)
ECOSAR v 1.11
Daphnia magna 48-hour LC50:
n=2: 1.4 mg/L
n=3: 0.52 mg/L
n=4: 0.18 mg/L
(ECOSAR class: Phenols)
(Estimated)
ECOSAR v 1.11
Estimate based on representative
oligomer n=l.
Estimates based on representative
oligomers n=2 through n=4. The
corresponding estimated effects
exceed the water solubilities (0.1
mg/L for n=2, 0.001 mg/L for n=3,
and 0.00001 mg/L for n=4) by more
than lOx. NES are predicted for
4-146
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
NES
(Estimated)
Professional judgment
these endpoints.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Green Algae EC50
Green algae 96-hour EC50:
14 mg/L (ECOSAR class: Phenols)
ECOSARvl.ll
Green algae 96-hour EC50:
n=2: 5.1 mg/L
n=3: 1.7 mg/L
n=4: 0.55 mg/L
(ECOSAR class: Phenols)
(Estimated)
ECOSARvl.ll
NES
(Estimated)
Professional judgment
Estimate based on representative
oligomer n=l.
Estimates based on representative
oligomers n=2 through n=4. The
corresponding estimated effects
exceed the water solubilities (0.1
mg/L for n=2, 0.001 mg/L for n=3,
and 0.00001 mg/L for n=4) by more
than lOx. NES are predicted for
these endpoints.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Chronic Aquatic Toxicity
HIGH: Based on estimated chronic aquatic toxicity values for fish, daphnia, and green algae using the
phenols SAR for representative structure, where n=l, with a MW <1,000. The high MW components, with
a MW>1,000 have low water solubility and are expected to have no effects at saturation (NES).
Fish ChV
Freshwater fish ChV:
0.77 mg/L (ECOSAR class: Phenols)
ECOSARvl.ll
Estimate based on representative
oligomer n=l.
4-147
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
ECOSARvl.ll
Freshwater fish ChV:
n=2: 0.23 mg/L
n=3: 0.06 mg/L
n=4: 0.02 mg/L
(ECOSAR class: Phenols)
(Estimated)
NES
(Estimated)
Professional judgment
Estimates based on representative
oligomers n=2 through n=4. The
estimated effect for n=2 exceeds the
water solubility of 0.1 mg/L, but not
by lOx as required to be considered
NES by ECOSAR. The chemical
may not be soluble enough to
measure the predicted effect. The
corresponding estimated effects for
n=3 and n=4 exceed the water
solubilities (0.001 mg/L and
0.00001 mg/L, respectively) by
more than lOx. NES are predicted
for these oligomers.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Daphnid ChV
Daphnia magna ChV:
0.67 mg/L (ECOSAR class: Phenols);
ECOSARvl.ll
Daphnia magna ChV:
n=2: 0.27 mg/L
n=3: 0.1 mg/L
n=4: 0.03 mg/L
(ECOSAR class: Phenols)
(Estimated)
ECOSARvl.ll
Estimate based on representative
oligomer n=l.
Estimates based on representative
oligomers n=2 through n=4. The
estimated effect for n=2 exceeds the
water solubility of 0.1 mg/L, but not
by lOx as required to be considered
NES by ECOSAR. The chemical
may not be soluble enough to
measure the predicted effect. The
corresponding estimated effects for
n=3 and n=4 exceed the water
solubilities (0.001 mg/L and
0.00001 mg/L, respectively) by
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Green Algae ChV
DATA
NES
(Estimated)
Green algae ChV:
6.5 mg/L (ECOSAR class: Phenols)
Green algae ChV:
n=2: 2.4 mg/L
n=3: 0.78 mg/L
n=4: 0.25 mg/L
(ECOSAR class: Phenols)
(Estimated)
NES
(Estimated)
REFERENCE
Professional judgment
ECOSAR v 1.11
ECOSAR v 1.11
Professional judgment
DATA QUALITY
more than lOx. NES are predicted
for these oligomers.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Estimate based on representative
oligomer n=l.
Estimates based on representative
oligomers n=2 through n=4. The
corresponding estimated effects
exceed the water solubilities (0.1
mg/L for n=2, 0.001 mg/L for n=3,
and 0.00001 mg/L for n=4) by more
than lOx. NES are predicted for
these endpoints.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
ENVIRONMENTAL FATE
4-149
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Transport
Henry's Law Constant (atm-
m3/mole)
Sediment/Soil
Adsorption/Desorption - Koc
Level III Fugacity Model
Persistence
Water
Aerobic Biodegradation
DATA
REFERENCE
DATA QUALITY
The estimated negligible water solubility and estimated negligible vapor pressure indicate that this
polymer is anticipated to partition predominantly to soil and sediment. The estimated Henry's Law
Constant of <10~8 atm-m3/mole indicates that it is not expected to volatilize from water to the atmosphere.
The estimated Koc of >30,000 indicates that it is not anticipated to migrate from soil into groundwater and
also has the potential to adsorb to sediment.
<10~8 for the n>5 oligomers (Estimated)
<10"8 for n= 1-4 (Estimated)
>3 0,000 for n= 1-4 (Estimated)
>3 0,000 for the n>5 oligomers
(Estimated)
Air = 0%
Water = 4.8%
Soil = 57%
Sediment = 39% (Estimated)
for n=l
Boethling and Nabholz, 1997;
Professional judgment
EPIv4.11
EPI v4. 1 1 ; Professional
judgment
Boethling and Nabholz, 1997;
Professional judgment
EPIv4.11
High MW polymers are expected to
have low vapor pressure and are not
expected to undergo volatilization.
Estimated value based on
representative structures with MW
< 1,000. Cutoff value for nonvolatile
compounds.
Estimated for the n>5 oligomers;
cutoff value used for large, high
MW polymers. High MW polymers
are expected to adsorb strongly to
soil and sediment.
Estimates based on a representative
structure where n=l. No data located
for the high MW component of the
polymers.
VERY HIGH: Although experimental data are not available, the high MW components of this polymer
(n>5; MW>1,000) are expected to be recalcitrant to biodegradation. Estimated half-lives for ultimate
aerobic biodegradation are >180 days for the n=l oligomer, representing MW <1,000 components of the
polymer. Degradation of this polymer by hydrolysis or direct photolysis is not expected to be significant as
the functional groups present do not tend to undergo these reactions under environmental conditions. The
atmospheric half-life is estimated to be <1 day; however, the polymer is not anticipated to partition
significantly to air.
Days-weeks (Primary Survey Model)
Weeks-months (Ultimate Survey Model)
(Estimated)
Recalcitrant
EPIv4.11
Boethling and Nabholz, 1997;
Estimates based on representative
oligomer where n=l .
High MW polymers are expected to
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Soil
Air
Reactivity
Volatilization Half-life for
Model River
Volatilization Half-life for
Model Lake
Aerobic Biodegradation
Anaerobic Biodegradation
Soil Biodegradation with
Product Identification
Sediment/Water
Biodegradation
Atmospheric Half-life
Photolysis
Hydrolysis
DATA
for n>5 oligomers (Estimated)
>1 year (Estimated)
>1 year (Estimated)
Not probable (Anaerobic-methanogenic
biodegradation probability model) for
n=l-4
Recalcitrant
for n>5 oligomers (Estimated)
<0.15 days (Estimated)
Not a significant fate process (Estimated)
>1 year (Estimated)
REFERENCE
Professional judgment
EPIv4. 11; Professional
judgment
EPI v4. 1 1 ; Professional
judgment
EPIv4.11
Boethling and Nabholz, 1997;
Professional judgment
EPIv4.11
Mill, 2000; Professional
judgment
Professional judgment
DATA QUALITY
be non-biodegradable.
Estimated value based on
representative structures with MW
< 1,000. Also, the high MW polymer
components are anticipated to be
nonvolatile.
Estimated value based on
representative structures with MW
< 1,000. Also, the high MW polymer
components are anticipated to be
nonvolatile.
No data located.
Estimates based on representative
oligomer where n=l-4.
High MW polymers are expected to
be resistant to removal under anoxic
conditions due to their limited
bioavailability.
No data located.
No data located.
Estimated value based on four
confidential representative structures
withMW
-------
Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Environmental Half-life
Bioaccumulation
Fish BCF
Other BCF
BAF
DATA
>1 year at pH 6
68 days at pH 7
6.8 days at pH 8
16 hours atpH9
(Estimated for n=l)
>75 days Half-life estimated for
representative structure where n=l; in the
predominant compartment, soil, as
determined by EPI and the PBT Profiler
methodology (Estimated)
REFERENCE
EPIv4.11
PBT Profiler vl.301; EPI v4. 1 1
DATA QUALITY
to an appreciable extent.
Hydrolysis rates are expected to be
pH-dependent and may be limited
by the low water solubility of this
compound. Under basic conditions,
sequential dephosphorylation
reactions may occur.
Half-life estimated for the
predominant compartment, soil, as
determined by EPI and the PBT
Profiler methodology.
HIGH: The estimated BCF and BAF for the low MW components (n=l-4; MW<1,000) result in a High
bioaccumulation designation. The higher MW oligomers that may be found in the polymeric mixture (n>5;
MW>1,000) are expected to have Low potential for bioaccumulation based on their large size and low
water solubility according to the polymer assessment literature and professional judgment.
6,600 for n=4 (Estimated)
1,500 forn=3 (Estimated)
360 forn=2 (Estimated)
85 forn=l (Estimated)
< 100 (Estimated)
2.1xl06 for n=4 (Estimated)
3.2xl04 for n=3 (Estimated)
EPIv4.11
EPIv4.11
EPIv4.11
EPIv4.11
Boethling and Nabholz, 1997;
Professional judgment
EPIv4.11
EPIv4.11
Estimates based on representative
structure where n=4.
Estimates based on representative
structure where n=3 .
Estimates based on representative
structure where n=2.
Estimates based on representative
structure where n=l.
Estimated for the oligomers with a
MW >1,000. Cutoff value for large,
high MW, insoluble polymers
according to polymer assessment
literature.
No data located.
Estimates based on representative
structure where n=4.
Estimates based on representative
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Fyrol PMP CASRN 63747-58-0
PROPERTY/ENDPOINT
Metabolism in Fish
DATA
1,200 forn=2 (Estimated)
170forn=l (Estimated)
REFERENCE
EPIv4.11
EPIv4.11
DATA QUALITY
structure where n=3 .
Estimates based on representative
structure where n=2.
Estimates based on representative
structure where n=l.
No data located.
ENVIRONMENTAL MONITORING AND BIOMONITORING
Environmental Monitoring
Ecological Biomonitoring
Human Biomonitoring
No data located.
No data located.
No data located.
4-153
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Boethling RS and Nabholz JV (1997) Environmental assessment of polymers under the U.S. Toxic Substances Control Act. Washington, DC: U.S.
Environmental Protection Agency.
ECOSAR Ecological Structure Activity Relationship (ECOSAR). Estimation Programs Interface (EPI) Suite for Windows, Version 1.11.
Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency, http://www.epa.gov/oppt/newchems/tools/21ecosar.htm.
EPA (1999) Determining the adequacy of existing data. High Production Volume (HPV) Challenge. Washington, DC: U.S. Environmental
Protection Agency, http://www.epa.gov/hpv/pubs/general/datadeqfn.pdf
EPA (2010) Screening level hazard characterization phosphoryl chloride, polymer with resorcinol phenyl ester.
http://www.epa.gov/chemrtk/hpvis/hazchar/125997219_Phosphoryl%20chloride,%20polymer%20with%20resorcinor/o20phenyr/o20ester_%20Ju
ne%202010.pdf.
EPA (2012) Using noncancer screening within the SF initiative. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/sf/pubs/noncan-screen.htm.
EPI Estimation Programs Interface (EPI) Suite, Version 4.11. Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency.
http://www.epa.gov/opptintr/exposure/pubs/episuitedl.htm.
ESIS (2012) European chemical Substances Information System. European Commission, http://esis.jrc.ec.europa.eu/.
Environment Agency (2009) Environmental risk evaluation report: Tetraphenyl resorcinol diphosphate (CAS no. 57586-54-7). Environment
Agency, http://cdn.environment-agency.gov.uk/scho0809bqul-e-e.pdf
European Commission (2012) EU priority list of suspected endocrine disrupters.
http://ec.europa.eu/environment/endocrine/strategy/substances_en.htm#priority_list.
Hsu HH (2013) Halogen-free flame-retardant epoxy resin composition, and prepreg and printed circuit board using the same. Owner name:
Taiwan Union Technology Corporation, Taiwan. United States Patent and Trademark Office. IFI CLAIMS Patent Services.
http://www.google.com/patents/US8581107.
ICL (2010) Material safety data sheet: Fyrol PMP. ICL Industrial Products, http://daatsolutions.info/brom2/wp-
content/uploads/2012/03/7042_enFyrol_PMP.pdf
ICL (2013) Brochure on flame retardants. ICL Industrial Products, www.iclfr.com.
Mill T (2000) Photoreactions in surface waters. In: Boethling R, Mackay D, eds. Handbook of Property Estimation Methods for Chemicals,
Environmental Health Sciences. Boca Raton: Lewis Publishers.:355-381.
4-154
-------
NTP (1994) NTP technical report on the toxicology and carcinogenesis studies of tricresyl phosphate in F344/N rats and B6C3F1 mice (Gavage
and feed studies).
PBT Profiler Persistent (P), Bioaccumulative (B), and Toxic (T) Chemical (PBT) Profiler, Version 1.301. Washington, DC: U.S. Environmental
Protection Agency, www.pbtprofiler.net.
Pakalin S, Cole T, Steinkeliner J, et al. (2007) Review on production processes of decabromodiphenyl ether (DECABDE) used in polymeric
applications in electrical and electronic equipment, and assessment of the availability of potential alternatives to DECABDE. European Chemicals
Bureau, European Commission, http://publications.jrc.ec.europa.eu/repository/bitstream/l 1111111 l/5259/l/EUR%2022693.pdf.
4-155
-------
D.E.R. 500 Series
VL = Very Low hazard L = Low hazard = Moderate hazard H = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion
by-products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the
table.
* The highest hazard designation of any of the oligomers with MW < 1,000. ¥ Aquatic toxicity: EPA/DfE criteria are based in large part upon water column exposures which may not
be adequate for poorly soluble substances such as many flame retardants that may partition to sediment and particulates.
Chemical
CASRN
Human Health Effects
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D.E.R. 500 Series*
26265-08-7 \L\M\M\M\M\M\M\
VH
4-156
-------
D.E.R. 500 Series
OH
Br
CASRN: 26265-08-7
MW: Average MW 900 (Measured)
MF: CsgH
MW=940
? as shown with n=l;
Physical Forms: Solid
Neat:
Use: Flame retardant
SMILES: OlCClCOc2ccc(cc2)C(C)(C)c3ccc(cc3)OCC(O)COc4c(Br)cc(cc4Br)C(C)(C)c5cc(Br)c(c(Br)c5)OCC6CO6 as shown with n = 1
Synonyms: Phenol, 4,4'(l-methylethylidene)bis[2,6-dibromo-, polymer with (chloromethyl)oxirane and 4,4'-(l-methylethylidene)bis[phenol] (The reaction product
of TBBPA), bisphenol A, epichlorohydrin and tetrabromobisphenol A polymer; Brominated epoxy resin; Epichlorohydrin, tetrabromobisphenol A polymer
Trade names: D.E.R.® 500 series epoxy resin; D.E.R. 538; Epikote 1145-B-70; EPON Resin 1123 (polymer of tetrabromobisphenol A epoxy resin, bisphenol A
diglycidyl ether, and epichlorohydrin)
The D.ER. 500 series epoxy resin product literature also lists CASRN 40039-93-8, Phenol, 4,4'-(l-methylethylidene)bis[2,6-dibromo-, polymer with 2-
(chloromethyl)oxirane; or Bisphenol A diglycidyl ether, brominated. This compound is a very close structural analog to Phenol, 4,4'(l-methylethylidene)bis[2,6-
dibromo-, polymer with (chloromethyl)oxirane and 4,4'-(l-methylethylidene)bis[phenol] (CASRN 26265-08-7).
Chemical Considerations: The D.E.R. 500 Series of polymers consist of components with MWs above and below 1,000 daltons.
The low MW components (MW <1,000) are expected to be present at levels requiring their assessment. The MW <1,000 components are assessed with EPI v4.11 and
ECOSAR vl. 11 estimates due to an absence of publicly available experimental physical/chemical, environmental fate and aquatic toxicity values. These include the
n=l component as shown in the SMILES entry and the n=0 component, as represented by the discrete organic 2,2',6,6'-tetrabromobisphenol A diglycidyl ether
(CASRN 3072-84-2).
The n>2 oligomers have a MW >1,000 and are assessed using the available polymer assessment literature.
Polymeric: Yes
Oligomeric: This is a tetrabromobisphenol A (TBBPA)-based epoxy resin; the oligomers are produced by reacting epichlorohydrin with bisphenol A (BPA) and
TBBPA (Dow, 2009).
Metabolites, Degradates and Transformation Products: None identified (Professional judgment)
Analog: None
Endpoint(s) using analog values: Not applicable
Analog Structure: Not applicable
4-157
-------
Structural Alerts: Polyhalogenated aromatic hydrocarbons: immunotoxicity; epoxy groups/epoxides: dermal sensitization, cancer, reproductive effects,
developmental toxicity (EPA, 2012; EPA, 2010).
Risk Phrases: Not classified by Annex VI Regulation (EC) No 1272/2008 (ESIS, 2012).
Hazard and Risk Assessments: None identified.
4-158
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
Water Solubility (mg/L)
>300
(Estimated)
<10"8 for MW <1,000 components
(Estimated)
<10"8 for the n>2 oligomers (Estimated)
3.3xlO~5 for a component (Estimated)
1.7xlO"9forn=l (Estimated)
<0.001
EPIv4.11;EPA, 1999
EPIv4.11;EPA, 1999
Boethling and Nabholz, 1997;
Professional judgment
EPIv4.11
EPIv4.11;EPA, 1999
Boethling and Nabholz, 1997;
No data located.
Estimates based on a representative
oligomer where n=l and for
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2), a component of the polymeric
mixture with a MW <1,000. Also
estimated for oligomers where n>2
with MWs >1,000. Cutoff value
according to HPV assessment
guidance and cutoff value used for
large, high MW solids.
Estimates based on representative
oligomer where n=l and for
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2), a component of the polymeric
mixture. Cutoff value for nonvolatile
compounds according to HPV
assessment guidance.
Cutoff value for large, high MW
polymers.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture.
Estimates based on representative
oligomer where n=l. Values are less
than the cutoff value, <0.001 mg/L,
for non-soluble compounds
according to HPV assessment
guidance.
Cutoff value for large, high MW
4-159
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Log Kow
Flammability (Flash Point)
Explosivity
Pyrolysis
pH
pKa
Particle Size
DATA
for the n>2 oligomers (Estimated)
7.4
for a component (Estimated)
11
forn=l (Estimated)
No data located;
for n>2 oligomers (Estimated)
Not flammable (Estimated)
Not expected to form explosive mixtures
with air (Estimated)
Not applicable (Estimated)
Not applicable (Estimated)
REFERENCE
Professional judgment
EPIv4.11
EPIv4.11;EPA, 1999
Professional judgment
Professional judgment
Professional judgment
Professional judgment
DATA QUALITY
non-ionic polymers.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture.
Estimates based on representative
oligomer where n=l. Estimated
value is greater than the cutoff
value, >10, according to
methodology based on HPV
assessment guidance.
Polymers with a MW > 1,000 are
outside the domain of the available
estimation methods.
No experimental data located; based
on its use as a flame retardant.
No experimental data located; based
on its use as a flame retardant.
No data located.
Does not contain functional groups
that are expected to ionize under
environmental conditions.
Does not contain functional groups
that are expected to ionize under
environmental conditions.
No data located.
4-160
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
HUMAN HEALTH EFFECTS
Toxicokinetics
Dermal Absorption in vitro
Absorption,
Distribution,
Metabolism &
Excretion
Oral, Dermal or Inhaled
Other
Acute Mammalian Toxicity
Acute Lethality
Oral
Dermal
No experimental data were located. Based on professional judgment, absorption is expected to be poor by
all routes for the low MW (<1,000) fraction. There is no absorption expected for any route of exposure for
the large MW >1,000 components.
Absorption is expected to be poor by all
routes for the low molecular weight
fraction. There is no absorption expected
for any route of exposure for the large,
high molecular weight (> 1,000) fraction.
(Estimated)
Professional judgment
Estimated based on professional
judgment.
No data located.
LOW: Estimated based on experimental data for a component of D.E.R., professional judgment and by
analogy to structurally similar polymers. The large MW components, with a MW >1,000, are expected to
have limited bioavailability and therefore have low potential for acute mammalian toxicity. There was no
data located regarding the inhalation route of exposure.
Rat oral LD50 > 2,000 mg/kg
Rat oral LD50 = 7,160 mg/kg
Rat oral LD50 >3,663 mg/kg
(Estimated by analogy)
Rat LD50 >2,000 mg/kg
(Estimated by analogy)
ECHA, 2014
Ash and Ash, 2009
Submitted confidential study;
Professional judgment
ECHA, 2014
Study details reported in a secondary
source; test substance identified as
F-2200HM (CASRN 3072-84-2) a
component of the polymeric
mixture; purity: 100%; conducted
according to OECD 423.
Limited study details reported in a
secondary source; data are for
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2), a component of the polymeric
mixture.
Based on closely related confidential
analogs with similar structures,
functional groups, and
physical/chemical properties.
Estimated based on analogy; Study
details reported in a secondary
4-161
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Inhalation
Carcinogenicity
OncoLogic Results
Carcinogenicity (Rat and
Mouse)
Combined Chronic
Toxicity/Carcinogenicity
Other
DATA
Rabbit LD50 >2,000 mg/kg
(Estimated by analogy)
REFERENCE
Submitted confidential study;
Professional judgment
DATA QUALITY
source for the test substance
bisphenol A diglycidyl ether,
brominated (CASRN 40039-93-8), a
very close structural analog.
Based on closely related confidential
analogs with similar structures,
functional groups, and
physical/chemical properties.
No data located.
MODERATE: There is uncertainty due to lack of data for this substance. In addition, there is potential for
Carcinogenicity based on a structural alert for epoxy groups/epoxides though this concern may be
mitigated by the high molecular weight; carcinogenic effects cannot be completely ruled out.
There is potential for Carcinogenicity
based on a structural alert for epoxy
groups/epoxides; however, the concern
may be mediated by the high molecular
weight.
(Estimated)
Professional judgment; EPA,
2010
Not amenable for OncoLogic
modeling.
No data located.
No data located.
Estimated based on a structural alert
for epoxy groups/epoxides and
professional judgment.
4-162
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D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Genotoxicity
MODERATE: There is uncertainty regarding the potential for genotoxicity due to the lack of sufficient
data for this substance. Conflicting results were reported for gene mutations; the test substance was
reported to be negative for gene mutations in one study, while there were positive results for gene
mutations in Ames and mouse lymphoma assays. There were also mixed results for sister chromatid
exchanges for analogs. There was no experimental chromosomal aberrations data for the test substance
located. Genotoxic effects cannot be completely ruled out; an estimated Moderate hazard designation was
assigned.
Gene Mutation in vitro
Negative, Salmonella typhimurium strains
TA98, TA100, TA1535, TA1537 and
TA1538 and E. coli strain WP2 uvrA
pKMlOl with and without metabolic
activation.
Negative, Salmonella typhimurium strains
TA98, TA100, TA1535, TA1537 andE.
coli strain WP2 uvrA pKMlOl with and
without metabolic activation.
(Estimated by analogy)
Positive, Ames assay
(Estimated by analogy)
Positive, mouse lymphoma test
(Estimated by analogy)
Gene Mutation in vivo
Chromosomal Aberrations in
vitro
Negative, chromosomal aberration test in
human lymphocytes with and without
metabolic activation
(Estimated by analogy)
4-163
Willett, 1991
ECHA, 2014
Submitted confidential study
Submitted confidential study
ECHA, 2014
Study details reported in the primary
source. Test substances reported as
Epikote 1145-B-70.
Estimated based on analogy; study
details reported in a secondary
source for the test substance
bisphenol A diglycidyl ether,
brominated (CASRN 40039-93-8), a
very close structural analog;
conducted according to OECD 471.
Limited study details reported in a
confidential study submitted to EPA.
Estimated based on a confidential
analog.
Limited study details reported in a
confidential study submitted to EPA.
Estimated based on a confidential
analog.
No data located.
Estimated based on analogy; study
details reported in a secondary
source for the test substance
bisphenol A diglycidyl ether,
brominated (CASRN 40039-93-8), a
very close structural analog;
conducted according to OECD 473.
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Chromosomal Aberrations in
vivo
DNA Damage and Repair
Other
Reproductive Effects
Reproduction/Developmental
Toxicity Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Reproduction and Fertility
Effects
Other
Developmental Effects
Reproduction/
Developmental Toxicity
Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
DATA
Positive, chromosomal aberration test in
human lymphocytes
(Estimated by analogy)
REFERENCE
Submitted confidential study
DATA QUALITY
Limited study details reported in a
confidential study submitted to EPA.
Estimated based on a confidential
analog.
No data located.
No data located.
No data located.
MODERATE: There is potential for reproductive toxicity for the low MW oligomers of the polymer
(<1,000) based on a structural alert for epoxy groups/epoxides.
There is potential for reproductive
toxicity based on a structural alert for
epoxy groups/epoxides.
(Estimated)
Professional judgment; EPA,
2010
No data located.
No data located.
No data located.
Estimated based on a structural alert
for epoxy groups/epoxides and
professional judgment.
MODERATE: There is potential for developmental toxicity for the low MW oligomers of the polymer
(<1,000) based on a structural alert for epoxides.
There were no data located for the developmental neurotoxicity endpoint.
No data located.
No data located.
4-164
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Prenatal Development
Postnatal Development
Prenatal and Postnatal
Development
Developmental Neurotoxicity
Other
Neurotoxicity
Neurotoxicity Screening
Battery (Adult)
Other
Repeated Dose Effects
DATA
No data was located for the
developmental neurotoxicity endpoint.
There is potential for developmental
toxicity based on a structural alert for
epoxy groups/epoxides
(Estimated)
REFERENCE
Professional judgment; EPA,
2010
DATA QUALITY
No data located.
No data located.
No data located.
No data located.
Estimated based on a structural alert
for epoxy groups/epoxides and
professional judgment.
MODERATE: There is potential for neurotoxicity for the lower MW components based on professional
judgment.
Potential for neurotoxicity
(Estimated)
Professional judgment
No data located.
Estimated based on the lower MW
components and professional
judgment.
MODERATE: Estimated to have potential for immunotoxicity based on a structural alert for
polyhalogenated aromatic hydrocarbons and liver effects for the lower MW components. A 28-day oral
study in rats for a very close structural analog, bisphenol A diglycidyl ether, brominated (CASRN 40039-
93-8) indicated effects in males (reduced body weight gain) at a dose of 1,000 mg/kg bw-day (NOAEL =
300 mg/kg bw-day).
Potential for liver effects
(Estimated)
Potential for immunotoxicity based on
structural alert for polyhalogenated
aromatic hydrocarbons.
(Estimated)
28-day oral (gavage) study in male and
female Wistar rats; 30, 300 and 1,000
mg/kg bw-day
Reduced body weight gain in males at
Professional judgment
Professional judgment; EPA,
2012
ECHA, 2014
Estimated based on the lower MW
components and professional
judgment.
Estimated based on structural alert
for polyhalogenated aromatic
hydrocarbons and professional
judgment.
Study details reported in a secondary
source for the test substance
bisphenol A diglycidyl ether,
brominated (CASRN 40039-93-8), a
4-165
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Skin Sensitization
Skin Sensitization
Respiratory Sensitization
[Respiratory Sensitization
DATA
1,000 mg/kg bw-day. Microscopic liver
changes (centrilobular hypertrophy) and
metabolic blood chemical changes
(increases in alanine aminotransferase,
aspartate aminotransferase or bile acids)
in males at 300 and 1,000 mg/kg bw-day
were not considered to be adverse health
effects.
NOAEL = 300 mg/kg bw-day (males)
LOAEL = 1,000 mg/kg bw-day (males,
based on reduction in body weight gain)
REFERENCE
DATA QUALITY
very close structural analog.
Conducted according to GLP and
OECD guideline 407.
HIGH: Positive for skin Sensitization in guinea pigs. In addition, there is an estimated potential for skin
Sensitization based on a structural alert for epoxy groups/epoxides.
Strong sensitizer, guinea pigs,
maximization test.
19/20 test animals showed positive
responses 24 hours after removal of
challenge patches and 16 continued to
have positive response at 48 hours.
Not sensitizing, mouse local lymph node
assay (LLNA)
There is potential for skin Sensitization
based on a structural alert for epoxy
groups/epoxide s .
(Estimated)
Willett, 1990
ECHA, 2014
Professional judgment
Adequate primary source; Test
substance reported as Epikote 1 120-
B-80.
Estimated based on analogy; Study
details reported in a secondary
source for the test substance
bisphenol A diglycidyl ether,
brominated (CASRN 40039-93-8), a
very close structural analog.
Estimated based on a structural alert
for epoxy groups/epoxides and
professional judgment.
No data located.
[No data located.
4-166
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Eye Irritation
Eye Irritation
Dermal Irritation
Dermal Irritation
Endocrine Activity
DATA
REFERENCE
DATA QUALITY
MODERATE: Estimated based on mixed results for studies using the component F-2200HM (2,2',6,6'-
tetrabromobisphenol A diglycidyl ether (CASRN 3072-84-2)). The structural analog, bisphenol A
diglycidyl ether, brominated (CASRN 40039-93-8), was not an eye irritant in rabbits.
Mildly irritating in rabbit eyes; reported
eye irritation was resolved within 72
hours.
Eye irritant
ECHA, 2014
Ash and Ash, 2009
Study details reported in a secondary
source; test substance identified as
the component F-2200HM
(2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2)); purity: 100%; conducted
according to OECD 404.
Reported in a secondary source with
limited details for the component
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2).
MODERATE: Estimated based on mixed results for studies using the component F-2200HM (2,2',6,6'-
tetrabromobisphenol A diglycidyl ether (CASRN 3072-84-2)).
Not a skin irritant in rabbits
Skin irritant
ECHA, 2014
Ash and Ash, 2009
Study details reported in a secondary
source; test substance identified as
the component F-2200HM
(2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2)); purity: 100%; conducted
according to OECD 404.
Limited study details reported in a
secondary source for the component
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2).
No data located.
[No data located.
4-167
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Immunotoxicity
Immune System Effects
DATA
REFERENCE
DATA QUALITY
Estimated to have potential for immunotoxicity based on a structural alert for polyhalogenated aromatic
hydrocarbons.
Potential for immunotoxicity based on
structural alert for polyhalogenated
aromatic hydrocarbons.
(Estimated)
Professional judgment; EPA,
2012
Estimated based on structural alert
for polyhalogenated aromatic
hydrocarbons and professional
judgment.
ECOTOXICITY
ECOSAR Class
Acute Aquatic Toxicity
Fish LC50
Epoxides, Poly
LOW: Non-ionic polymers with a MW >1,000 and negligible water solubility are estimated to display no
effects at saturation (NES). These polymers display NES because the amount dissolved in water is not
anticipated to reach a concentration at which adverse effects may be expressed. Guidance for the
assessment of aquatic toxicity hazard leads to a low potential for those materials that display NES. The
estimated acute toxicity values for fish, daphnid, and algae for the low MW components of the polymer
(<1,000) also suggest no effects at saturation (NES).
NES
(Estimated)
Freshwater fish 14-day LC50= 0.008
mg/L
(Estimated)
ECOSAR: Epoxides, Poly
Freshwater fish 96-hour LC50 = IxlO"5
mg/L
(Estimated)
ECOSAR: Neutral organics
Professional judgment
ECOSAR v 1.11
ECOSAR v 1.11
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Estimate based on representative
oligomer n=l. NES: The log Kow of
1 1 for this chemical exceeds the
SAR limitation for the log Kow of
5.0. In addition, the estimated effect
exceeds the water solubility of
1.68xlO"9mg/L by more than lOx.
NES are predicted for these
endpoints.
Estimate based on representative
oligomer n=l. NES: The log Kow of
1 1 for this chemical exceeds the
SAR limitation for the log Kow of
5.0. In addition, the estimated effect
exceeds the water solubility of
1.68xlO"9mg/L by more than lOx.
4-168
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Freshwater fish 14-day LC50 = 0.08 mg/L
(Estimated)
ECOSAR: Epoxides, poly
ECOSARvl.ll
Freshwater fish 96-hour LC50 = 0.008
mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSARvl.ll
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture. NES: The log Kow of 7.4
for this chemical exceeds the SAR
limitation for the log Kow of 5.0. In
addition, the estimated effect
exceeds the water solubility of
3.26xlO"5mg/L by more than lOx.
NES are predicted for these
endpoints.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2). NES:
The log Kow of 7.4 for this chemical
exceeds the SAR limitation for the
log Kow of 5.0. In addition, the
estimated effect exceeds the water
solubility of 3.26xlO"5mg/L by more
than lOx. NES are predicted for
these endpoints.
Narcosis classes (neutral organics)
are provided for comparative
4-169
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Daphnid LC50
NES
(Estimated)
Professional judgment
Daphnia magnet 48-hour LC50= 0.00065
mg/L
(Estimated)
ECOSAR: Epoxides, poly
ECOSAR v 1.11
Daphnia magna 48-hour LC50=1.28xlO"5
mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSAR v 1.11
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Estimate based on representative
oligomer n=l. NES: The log Kow of
11 for this chemical exceeds the
SAR limitation for the log Kow of
5.0. In addition, the estimated effect
exceeds the water solubility of
1.68xlO"9 mg/L by more than lOx.
NES are predicted for these
endpoints.
Estimate based on representative
oligomer n=l. NES: The log Kow of
11 for this chemical exceeds the
SAR limitation for the log Kow of
5.0. In addition, the estimated effect
exceeds the water solubility of
1.68xlO'9 mg/L by more than lOx.
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
4-170
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Daphnia magnet 48-hour LC50 = 0.036
mg/L
(Estimated)
ECOSAR: Epoxides, poly
ECOSARvl.ll
Daphnia magna 48-hour LC50 = 0.007
mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSARvl.ll
narcosis.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture. NES: The log Kow of 7.4
for this chemical exceeds the SAR
limitation for the log Kow of 5.0. In
addition, the estimated effect
exceeds the water solubility of
3.26xlO"5 mg/L by more than lOx.
NES are predicted for these
endpoints.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2). NES:
The log Kow of 7.4 for this chemical
exceeds the SAR limitation for the
log Kow of 5.0. In addition, the
estimated effect exceeds the water
solubility of 3.26x10"5 mg/L by
more than lOx. NES are predicted
for these endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Green Algae EC s
NES
(Estimated)
Professional judgment
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
4-171
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Green algae 96-hour EC50 = 0.00027
mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSARvl.ll
Green algae 96-hour EC50 = 0.041 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSARvl.ll
Estimate based on representative
oligomer n=l. NES: The log Kow of
11 for this chemical exceeds the
SAR limitation for the log Kow of
6.4. In addition, the estimated effect
exceeds the water solubility of
1.68xlO"9 mg/L by more than lOx.
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture. NES: The log Kow of 7.4
for this chemical exceeds the SAR
limitation for the log Kow of 6.4. In
addition, the estimated effect
exceeds the water solubility of
3.26xlO"5 mg/L by more than lOx.
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
4-172
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Chronic Aquatic Toxicity
Fish ChV
DATA
REFERENCE
DATA QUALITY
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
LOW: Non-ionic polymers with a MW >1,000 and negligible water solubility are estimated to display NES.
These polymers display NES because the amount dissolved in water is not anticipated to reach a
concentration at which adverse effects may be expressed. Guidance for the assessment of aquatic toxicity
hazard leads to a low potential for those materials that display NES. The estimated chronic toxicity values
for fish, daphnid, and algae for the low MW components of the polymer (<1,000) also suggest no effects at
saturation (NES).
NES
(Estimated)
Freshwater fish ChV = 2.7x1 0"5 mg/L
(Estimated)
ECOSAR: Epoxides, poly
Freshwater fish ChV =2.5xlO'6 mg/L
(Estimated)
ECOSAR: Neutral organics
Professional judgment
ECOSAR v 1.11
ECOSAR v 1.11
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Estimate based on representative
oligomer n=l. NES: The log Kow of
1 1 for this chemical exceeds the
SAR limitation for the log Kow of
8.0. In addition, the estimated effect
exceeds the water solubility of
1.68xlO~9 mg/L by more than lOx.
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimate based on representative
oligomer n=l. NES: The log Kow of
1 1 for this chemical exceeds the
SAR limitation for the log Kow of
4-173
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Freshwater fish ChV = 0.0008 mg/L
(Estimated)
ECOSAR: Epoxides, poly
ECOSARvl.ll
Freshwater fish ChV = 0.0013 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSARvl.ll
8.0. In addition, the estimated effect
exceeds the water solubility of
1.68xlO"9 mg/L by more than lOx.
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture. The estimated effect
exceeds the water solubility of
3.26xlO'5 mg/L by lOx. NES are
predicted for these endpoints.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2). The
estimated effect exceeds the water
solubility of 3.26x10"5 mg/L by
more than lOx. NES are predicted
for these endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
4-174
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
specific mode of action relative to
narcosis.
Daphnid ChV
NES
(Estimated)
Professional judgment
Daphnia magna ChV: = 3.2xlO~5 mg/L
(Estimated)
ECOSAR: Epoxides, poly
ECOSARvl.ll
Daphnia magna ChV = 1.2xlO~5 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSARvl.ll
Daphnia magna ChV = 0.002 mg/L
(Estimated)
ECOSAR: Epoxides, poly
4-175
ECOSARvl.ll
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Estimate based on representative
oligomer n=l. NES: The log Kow of
11 for this chemical exceeds the
SAR limitation for the log Kow of
8.0. In addition, the estimated effect
exceeds the water solubility of
1.68xlO"9 mg/L by more than lOx.
NES are predicted for these
endpoints.
Estimate based on representative
oligomer n=l. NES: The log Kow of
11 for this chemical exceeds the
SAR limitation for the log Kow of
8.0. In addition, the estimated effect
exceeds the water solubility of
1.68xlO"9 mg/L by more than lOx.
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2). The
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Green Algae ChV
DATA
Daphnia magna ChV = 0.003 mg/L
(Estimated)
ECOSAR: Neutral organics
21-dayEC50>23(ig/L
Considered effects on Daphnia magna
immobility and reproduction
Static conditions; 1.9, 3.8, 7.5, 15, 30
(ig/L (nominal concentration).
(Estimated by analogy)
NES
(Estimated)
Green algae ChV: 0.00044 mg/L
REFERENCE
ECOSAR v 1.11
ECHA, 2014
Professional judgment
ECOSAR v 1.11
DATA QUALITY
estimated effect exceeds the water
solubility of 3. 26x1 0"5 mg/L by
more than lOx. NES are predicted
for these endpoints.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture. The estimated effect
exceeds the water solubility of
3.26xlO"5 mg/L by more than lOx.
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Reported for bisphenol A diglycidyl
ether, brominated (CASRN 40039-
93-8), a close structural analog.
Study was conducted in accordance
with OECD Guideline 211; Daphnia
magna Reproduction Test and GLP.
The estimated effect exceeds the
water solubility by lOx. NES are
predicted for these endpoints.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES
for the MW >1,000 components.
Estimate based on representative
4-176
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
(Estimated)
ECOSAR: Neutral Organic SAR
Green algae ChV = 0.033 mg/L
(Estimated)
ECOSAR: Neutral organics
ECOSAR v 1.11
72-hour EC50>30(ig/L
ECHA, 2014
oligomer n=l. NES: The log Kow of
11 for this chemical exceeds the
SAR limitation for the log Kow of
8.0. In addition, the estimated effect
exceeds the water solubility of
1.68xlO"9 mg/L by more than lOx.
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture. The estimated effect
exceeds the water solubility of
3.26xlO"5 mg/L by more than lOx.
NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Reported for bisphenol A diglycidyl
4-177
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
Considered effects on area under the
growth curve, yield and growth rate
relative to the negative control group in
Pseudokirchneriella subcapitata
Static conditions; 1.8, 3.9, 7.6, 15, 24, 30
(ig/L (nominal concentration).
(Estimated by analogy)
REFERENCE
DATA QUALITY
ether, brominated (CASRN 40039-
93-8) a close structural analog.
Study was conducted in accordance
with OECD Guideline 201 (Alga,
Growth Inhibition Test) and GLP.
The estimated effect exceeds the
water solubility by lOx. NES are
predicted for these endpoints.
ENVIRONMENTAL FATE
Transport
Henry's Law Constant (atm-
m3/mole)
Sediment/Soil
Adsorption/Desorption - Koc
The estimated negligible water solubility, the estimated negligible vapor pressure and the estimated K0c of
>30,000 indicate the components of this polymer are anticipated to partition predominantly to soil and
sediment and these components are not anticipated to migrate from soil into groundwater. The estimated
Henry's Law constant values of <10"8 atm-m3/mole indicate that the polymer components are not expected
to volatilize from water to the atmosphere.
2 oligomers (Estimated)
>3 0,000 for MW < 1,000 components
(Estimated)
>30,000 forn>2 (Estimated)
EPIv4. 11; Professional
judgment
Boethling and Nabholz, 1997;
Professional judgment
EPIv4. 11; Professional
judgment
Boethling and Nabholz, 1997;
Professional judgment
Estimates based on representative
oligomer where n=l and for
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2), a component of the polymeric
mixture. Cutoff value for nonvolatile
compounds.
High MW polymers are expected to
have low vapor pressure and are not
expected to undergo volatilization.
Estimates based on representative
oligomer where n=l and for
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2), a component of the polymeric
mixture. Cutoff value fornonmobile
compounds.
Estimated for the n=2 oligomers;
cutoff value used for large, high
MW polymers. High MW polymers
are expected to adsorb strongly to
4-178
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Level III Fugacity Model
DATA
2 15, 000 for n=l
>430,000forn=2and3
Reported for components of the mixture.
According to OECD Guideline 121;
Estimation of the Adsorption Coefficient
on Soil and on Sewage Sludge using High
Performance Liquid Chromatography
(HPLC). (Estimated by analogy)
Air = 0%
Water = 3. 3%
Soil = 88%
Sediment = 8.4% (Estimated)
Air = 0%
Water =3%
Soil = 60%
Sediment = 37% (Estimated)
REFERENCE
ECHA, 2014
EPIv4.11
EPIv4.11
DATA QUALITY
soil and sediment.
Adequate guideline study reported
for bisphenol A diglycidyl ether,
brominated (CASRN 40039-93-8).
The three components in this study
are close structural analogs to the
components of D.E.R. 500 Series
(CASRN 26265-08-7).
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture.
Estimates based on representative
oligomer where n=l .
4-179
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Persistence
VERY HIGH: Experimental data are not available. Estimated half-lives for ultimate aerobic
biodegradation are >180 days for the n=l oligomer and 2,2',6,6'-tetrabromobisphenol A diglycidyl ether
(CASRN 3072-84-2), representing MW <1,000 components of the polymeric mixture. Polymeric
components with a MW >1,000 are expected to have negligible water solubility and poor bioavailability to
microorganisms indicating that neither biodegradation nor hydrolysis are expected to be important
removal processes in the environment. Although debromination by photodegradation of polybrominated
benzenes has been observed, this process is not anticipated to lead to ultimate removal of the polymer. The
estimated degradation half-life by hydrolysis is also expected to be >1 year. Degradation of this polymer by
direct photolysis is not expected to be significant as the functional groups present do not tend to undergo
these reactions under environmental conditions. The atmospheric half-life is estimated to be <2 days;
however, the polymer is not anticipated to partition significantly to air.
Water
Aerobic Biodegradation
Passes Ready Test: No
Test method: OECD TG 301B: CO2
Evolution Test
-2.4% degradation after 28 days in
activated sludge. (Estimated by analogy)
Months (Primary Survey Model)
Recalcitrant (Ultimate Survey Model)
(Estimated)
Recalcitrant for the n=2 oligomers
(Estimated)
Microbial toxicity/inhibition: Water-
leachates of the polymer inhibited
bacterial growth by 8%. (Measured)
ECHA, 2014
EPIv4.11
Boethling and Nabholz, 1997
Willett, 1990
Adequate guideline study reported
for bisphenol A diglycidyl ether,
brominated (CASRN 40039-93-8), a
very close structural analog.
Estimates based on representative
oligomer where n=l and 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture.
Estimated for the n>2 oligomers;
high MW polymers are expected to
have low vapor pressure and are not
expected to undergo volatilization.
The study was performed on water-
leachates of the polymer, and not on
the polymer itself. Given the low
water solubility of the polymer, it is
not anticipated to be present in the
leachate.
4-180
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Soil
Air
Volatilization Half-life for
Model River
Volatilization Half-life for
Model Lake
Aerobic Biodegradation
Anaerobic Biodegradation
Soil Biodegradation with
Product Identification
Sediment/Water
Biodegradation
Atmospheric Half-life
DATA
>1 year (Estimated)
>1 year (Estimated)
Not probable (Estimated)
1 .4 hours (Estimated)
0.6 days (Estimated)
REFERENCE
EPIv4.11
EPIv4.11
Holliger et al, 2004
EPIv4.11
EPIv4.11
DATA QUALITY
Estimates based on representative
oligomer where n=l and for
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2), a component of the polymeric
mixture.
Estimates based on representative
oligomer where n=l and for
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2), a component of the polymeric
mixture.
No data located.
The estimated value addresses the
potential for ultimate
biodegradation. However, there is
potential for primary anaerobic
biodegradation of the lower MW
(<1,000) haloaromatic compounds
by reductive dehalogenation.
No data located.
No data located.
Estimates based on representative
oligomer where n=l. This
compound is anticipated to exist as a
solid particulate in the atmosphere,
degradation by gas-phase reactions
are not expected to be important
removal processes.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
4-181
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
mixture. This compound is
anticipated to exist as a solid
particulate in the atmosphere,
degradation by gas-phase reactions
are not expected to be important
removal processes.
Reactivity
Photolysis
Not a significant fate process (Estimated)
Professional judgment
Hydrolysis
50%/>1 year at pH 7 (Estimated)
EPIv4.11
Bromine substituents may be
susceptible to photolysis in the
environment; however, this is
expected to be a relatively slow
process for a high MW brominated
epoxy polymer and is not anticipated
to result in the ultimate degradation
of this substance.
Estimates based on representative
oligomer where n=l and for
2,2',6,6'-tetrabromobisphenol A
diglycidyl ether (CASRN 3072-84-
2), a component of the polymeric
mixture. The estimated hydrolysis
rate is for the epoxide functional
group; hydrolysis is not expected to
be an important fate process for
other parts of the polymer.
Environmental Half-life
>180 days for the n>2 oligomers
(Estimated)
Professional judgment
>1 year in soil; for the n=l oligomer
(Estimated)
4-182
PBT Profiler v 1.301
Estimated for the n>2 oligomers; the
substance is a high MW polymer
and is not anticipated to be
assimilated by microorganisms.
Therefore, biodegradation is not
expected to be an important removal
process. It is also not expected to
undergo removal by other
degradative processes under
environmental conditions.
Half-life estimated for the n=l
oligomer for the predominant
-------
D.E.R. 500 Series CASRN 26265-08-7
PROPERTY/ENDPOINT
Bioaccumulation
Fish BCF
Other BCF
BAF
Metabolism in Fish
DATA
REFERENCE
DATA QUALITY
compartment, soil, as determined by
EPI and the PBT Profiler
methodology.
HIGH: The estimated BCF and BAF for 2,2',6,6'-tetrabromobisphenol A diglycidyl ether (CASRN 3072-
84-2), a component of the polymeric mixture and BAF for the n=l component are >1,000 resulting in a
High bioaccumulation designation. The higher MW oligomers that may be found in this mixture (n>2) are
expected to have Low potential for bioaccumulation based on their large size and low water solubility
according to the polymer assessment literature and professional judgment.
8,400 for a component (Estimated)
100forn=l (Estimated)
<100 for the n>2 oligomers (Estimated)
9.7xl06 for a component (Estimated)
69,000 forn=l (Estimated)
EPIv4.11
EPIv4.11
Boethling and Nabholz, 1997;
Professional judgment
EPIv4.11
EPIv4.11
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture.
Estimates based on representative
oligomer where n=l .
Estimated for the n>2 oligomers.
Cutoff value for large, high MW,
insoluble polymers according to
polymer assessment literature.
No data located.
Estimated for 2,2',6,6'-
tetrabromobisphenol A diglycidyl
ether (CASRN 3072-84-2), a
component of the polymeric
mixture.
Estimates based on representative
oligomer where n=l .
No data located.
ENVIRONMENTAL MONITORING AND BIOMONITORING
Environmental Monitoring
Ecological Biomonitoring
Human Biomonitoring
No data located.
No data located.
This chemical was not included in the NHANES biomonitoring report. (CDC, 2013).
4-183
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4-184
-------
Ash M and Ash I (2009) Specialty chemicals source book. 4th ed. Endicott, NY: Synapse Information Resources, Inc.: 1844.
Boethling RS and Nabholz JV (1997) Environmental assessment of polymers under the U.S. Toxic Substances Control Act. Washington, DC: U.S.
Environmental Protection Agency.
CDC (2013) Fourth national report on human exposure to environmental chemicals, updated tables, March 2013.
http://www.cdc.gov/exposurereport/pdf/FourthReport_UpdatedTables_Mar2013.pdf
Dow (2009) Product safety assessment Brominated epoxy resins.
ECHA (2014) [2,2',6,6'-Tetrabromo-4,4'-isopropylidenediphenol, oligomeric reaction products with l-chloro-2,3-epoxypropane]. Registered
substances. European Chemicals Agency. http://apps.echa.europa.eu/registered/data/dossiers/DISS-dffb4072-e4c5-47ae-e044-
00144f67d031/AGGR-5c653501-06d9-4709-b33b-d53dcd845elO_DISS-dffb4072-e4c5-47ae-e044-00144f67d031.html#section_l.l.
ECOSAR Ecological Structure Activity Relationship (ECOSAR). Estimation Programs Interface (EPI) Suite for Windows, Version 1.11.
Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency, http://www.epa.gov/oppt/newchems/tools/21ecosar.htm.
EPA (1999) Determining the adequacy of existing data. High Production Volume (HPV) Challenge. Washington, DC: U.S. Environmental
Protection Agency, http://www.epa.gov/hpv/pubs/general/datadeqfn.pdf
EPA (2010) TSCA new chemicals program (NCP) chemical categories. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/newchems/pubs/npcchemicalcategories.pdf
EPA (2012) Using noncancer screening within the SF initiative. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/sf/pubs/noncan-screen.htm.
EPI Estimation Programs Interface (EPI) Suite, Version 4.11. Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency.
http://www.epa.gov/opptintr/exposure/pubs/episuitedl.htm.
ESIS (2012) European chemical Substances Information System. European Commission, http://esis.jrc.ec.europa.eu/.
Holliger C, Regeard C, Diekert G (2004) Dehalogenation by anaerobic bacteria. In: Haggblom MM, Bossert ID, eds. Dehalogenation: Microbial
processes and environmental applications. Kluwer Academic Publishers.: 115-157.
PBT Profiler Persistent (P), Bioaccumulative (B), and Toxic (T) Chemical (PBT) Profiler, Version 1.301. Washington, DC: U.S. Environmental
Protection Agency, www.pbtprofiler.net.
4-185
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Willett JC (1990) Toxicity of resins: The skin sensitizing potential of "Epikote" 1120-B-80. Shell Oil Company Submitted to the US EPA under
TSCA Section 8D.
Willett JC (1991) Bacterial mutagenicity studies with Epikote 1145-8-70 with cover sheets and letter dated 010891. Prepared by Shell Research
for Shell Oil Company Submitted to the US EPA under TSCA Section 8D.
4-186
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VL = Very Low hazard L = Low hazard = Moderate hazard H = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion
by-products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the
table.
§ Based on analogy to experimental data for a structurally similar compound. * The highest hazard designation of any of the oligomers with MW <1,000. ¥ Aquatic toxicity: EPA/DfE
criteria are based in large part upon water column exposures which may not be adequate for poorly soluble substances such as many flame retardants that may partition to sediment
and particulates.
Chemical
CASRN
Human Health Effects
ute Toxicity
u
•<
rcinogenicit
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U
notoxicity
u
O
productive
O
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0)
0
urological
0)
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o
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isitization
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o
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0
Aquatic
Toxicity
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Environmental
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Confidential
M%
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H
VH
4-187
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Dow XZ-92547
SMILES: Confidential SMILES notations for representative structures of the MW < 1,000 components
CASRN: Confidential CASRN
MW: > 1,000; with a significant
percentage of components
having MW<1,000
MF: Confidential MF
Physical Forms: Solid
Neat:
Use: Flame retardant
Synonyms: Reaction product of an epoxy phenyl novolak with DOPO
Chemical Considerations: This alternative is a polymer consisting of components with MWs above and below 1,000 daltons. Lower MW components are expected
to be present at a level requiring their assessment. The components with a MW <1,000 are evaluated as four proprietary representative structures. In general, the
representative structures are different combinations of epoxy phenyl novolak and DOPO. These are assessed with EPI v4.11 andECOSARvl.il estimates due to an
absence of publicly available experimental physical/chemical, environmental fate and aquatic toxicity values. The oligomers with a MW >1,000 and are assessed
using the available polymer assessment literature.
Polymeric: Yes
Oligomeric: This polymer contains oligomers that are formed by the reaction of an epoxy phenyl novolak with DOPO.
Metabolites, Degradates and Transformation Products: None
Analog: None Analog Structure: Not applicabl
Endpoint(s) using analog values: Not applicable
Structural Alerts: Phosphinate esters - environmental toxicity; Epoxy groups/epoxides - dermal sensitization, cancer,
Organophosphorus compounds - neurotoxicity. (EPA, 2010; EPA, 2012).
e
reproductive effects, developmental toxicity;
Risk Phrases: Not classified by Annex VI Regulation (EC) No 1272/2008 (ESIS, 2012).
Hazard and Risk Assessments: None located.
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
Water Solubility (mg/L)
89 (Measured)
>300
(Estimated)
<10"8 (Estimated)
<10'8 (Estimated)
0.62
(Estimated)
0.0023
(Estimated)
7.7X10'6 (Estimated)
0.0082 (Estimated)
<0.001
(Estimated)
Submitted confidential study
EPIv4.11;EPA, 1999
EPA, 1999;EPIv4.11
Boethling and Nabholz, 1997;
Professional judgment
EPIv4.11
EPIv4.11
EPIv4.11;EPA, 1999
EPIv4.11;EPA, 1999
Boethling and Nabholz, 1997;
Professional judgment
Adequate, measured value from
submitted study.
Estimate based on four
representative structures with MW
< 1,000. Also estimated for
oligomers with MWs > 1,000. Cutoff
value according to HPV assessment
guidance and cutoff value used for
large, high MW solids.
Estimates based on four confidential
representative structures with MW
< 1,000. Cutoff value for nonvolatile
compounds according to HPV
assessment guidance.
Cutoff value for large, high MW
polymer components.
Estimates based on confidential
representative structure 1 with MW
<1,000.
Estimates based on confidential
representative structure 2 with MW
<1,000.
Estimates based on confidential
representative structure 3 with MW
< 1,000. Estimated value is less than
the cutoff value, <0.001 mg/L, for
non-soluble compounds according to
HPV assessment guidance.
Estimates based on confidential
representative structure 4 with MW
<1,000.
Cutoff value for large, high MW
non-ionic polymer components.
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PROPERTY/ENDPOINT
Log Kow
Flammability (Flash Point)
Explosivity
Pyrolysis
pH
pKa
Particle Size
DATA
3.7
(Estimated)
5.3
(Estimated)
7
(Estimated)
4.8
(Estimated)
Not flammable (Estimated)
Not expected to form explosive mixtures
with air (Estimated)
Not applicable (Estimated)
Not applicable (Estimated)
REFERENCE
EPIv4.11
EPIv4.11
EPIv4.11
EPIv4.11
Professional judgment
Professional judgment
Professional judgment
Professional judgment
DATA QUALITY
Estimates based on confidential
representative structure 1 with a
MW<1,000.
Estimates based on confidential
representative structure 2 with a
MW<1,000.
Estimates based on confidential
representative structure 3 with a
MW<1,000.
Estimates based on confidential
representative structure 4 with a
MW<1,000.
Mo experimental data located; based
on its use as a flame retardant.
No experimental data located; based
on its use as a flame retardant.
""Jo data located.
Does not contain functional groups
that are expected to ionize under
environmental conditions.
Does not contain functional groups
that are expected to ionize under
environmental conditions.
""Jo data located.
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
HUMAN HEALTH EFFECTS
Toxicokinetics
Dermal Absorption in vitro
Absorption,
Distribution,
Metabolism &
Excretion
Oral, Dermal or Inhaled
Other
Acute Mammalian Toxicity
Acute Lethality
Oral
Dermal
Inhalation
Based on the physical/chemical properties of this polymer, the higher MW fraction (>1,000) is estimated to
have limited bioavailability. Based on the physical/chemical properties, absorption is expected to be
negligible by all routes for the neat material and poor by all routes for the low molecular weight fraction if
in solution.
Absorption is expected to be negligible
by all routes for the neat material and
poor by all routes for the low MW
fraction if in solution.
(Estimated)
Professional judgment
Estimated based on professional
judgment.
No data located.
LOW: Based on experimental data that reported LD50 >2,000 mg/kg when administered orally and
dermally to rats. There were no data located for the inhalation route of exposure. The higher MW
components of this polymer (MW >1,000) are expected to have limited bioavailability and have low
potential for acute toxicity.
Estimated to have a low potential for
acute toxicity for the high MW
component. Limited bioavailability
expected.
(Estimated)
Rat, oral LD50 >2,000 mg/kg.
Rat, dermal LD50 >2,000 mg/kg.
Rat, dermal LD50 >2,000 mg/kg.
Boethling and Nabholz, 1997;
Professional judgment
Submitted confidential study
Submitted confidential study
Submitted confidential study
Estimated for the high MW
component (MW >1,000) based on
cutoff value for large, high MW
non-ionic polymer components.
Limited study details reported in a
confidential study.
Study details reported in a
confidential study.
Limited study details reported in a
confidential study.
^o data located.
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PROPERTY/ENDPOINT
Carcinogenicity
OncoLogic Results
Carcinogenicity (Rat and
Mouse)
Combined Chronic
Toxicity/Carcinogenicity
Other
DATA
REFERENCE
DATA QUALITY
MODERATE: There were no experimental data located for this substance. Carcinogenic effects cannot be
ruled out; therefore, uncertainty due to lack of data for this substance results in a Moderate designation.
In addition, there is an estimated potential for Carcinogenicity based on a structural alert for epoxy
groups/epoxides and for the low MW components (MW < 1,000). The higher MW components of this
polymer (MW >1,000) are expected to have limited bioavailability and have low potential for
Carcinogenicity.
Potential for Carcinogenicity based on a
structural alert for epoxy
groups/epoxides.
(Estimated)
Potential for Carcinogenicity for the low
MW components.
(Estimated)
Estimated to have a low potential for
Carcinogenicity for the high MW
component. Limited bioavailability
expected.
(Estimated)
Professional judgment; EPA,
2010
Professional judgment
Boethling and Nabholz, 1997;
Professional judgment
No data located.
No data located.
No data located.
Estimated based on a structural alert
for epoxy groups/epoxides and
professional judgment.
Estimated for the low MW
components based on professional
ludgment.
Estimated for the high MW
component (MW >1,000) based on
professional judgment and the cutoff
value for large, high MW non-ionic
3olymer components.
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Genotoxicity
MODERATE: Estimated based on positive gene mutation results for a confidential analog of the low MW
components (MW < 1,000) reported in a submitted confidential study. There were no gene mutation or
chromosomal aberrations data located for this substance. Negative results for mutagenicity and
chromosomal aberrations in vitro were reported in experimental data for the analog DOPO (CASRN
35948-25-5). In the absence of data for this substance and conflicting results reported for two analogs, a
conservative approach is used to assign a Moderate designation. The higher MW components of this
polymer (MW >1,000) are expected to have limited bioavailability and have low potential for genotoxicity.
Gene Mutation in vitro
Gene Mutation in vivo
There is potential for mutagenicity for the
low MW components.
Positive in Ames assay.
(Estimated by analogy)
Negative in Ames assay in Salmonella
typhimurium strains TA97, TA98,
TA100, and TA102 and Escherichia coli
WP2 uvr A pKM 101 with and without
metabolic activation. Tested up to 5,000
(ig/plate (purity, industrial grade).
Positive controls responded as expected.
(Estimated by analogy)
Negative in Ames assay; in Salmonella
typhimurium strains TA1535, TA97a,
TA98, TA100, and TA102 with and
without metabolic activation. Tested up to
5,024 (ig/plate (purity >99%). Positive
controls responded as expected.
(Estimated by analogy)
Professional judgment;
Submitted confidential study
ECHA, 2013
ECHA, 2013
Estimated based on experimental
data for a confidential analog for the
low MW components; reported in a
submitted confidential study and
srofessional judgment.
Estimated based on analogy to
DOPO (CASRN 35948-25-5).
Sufficient study details reported in a
secondary source. Non-GLP study,
3ut adequate as supporting data.
Estimated based on analogy to
DOPO (CASRN 35948-25-5).
Sufficient study details reported in a
secondary source. Study conducted
in accordance with OECD guideline
471 and GLP. Test substance was
CASRN 35948-25-5 named Ukanol
GK-F in study report. Primary
reference not identified.
No data located.
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PROPERTY/ENDPOINT
Chromosomal Aberrations in
vitro
Chromosomal Aberrations in
vivo
DNA Damage and Repair
Other
Reproductive Effects
Reproduction/Developmental
Toxicity Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Reproduction and Fertility
Effects
Other
DATA
Negative in Chinese hamster lung cells
with and without activation. Tested up to
216 (ig/mL (purity not provided). Positive
controls responded as expected.
(Estimated by analogy)
Estimated to have a low potential for
genotoxicity for the high MW
component. Limited bioavailability
expected.
(Estimated)
REFERENCE
ECHA, 2013
Boethling and Nabholz, 1997;
Professional judgment
DATA QUALITY
Estimated based on analogy to
DOPO (CASRN 35948-25-5).
Sufficient study details reported in a
secondary source. Study equivalent
to OECD Guideline 473; not a GLP
study.
No data located.
No data located.
Estimated for the high MW
component (MW >1,000) based on
srofessional judgment and the cutoff
value for large, high MW non-ionic
3olymer components.
MODERATE: There is an estimated potential for reproductive toxicity based on a structural alert for
epoxy groups/epoxides and an estimated potential for male reproductive toxicity for the low MW
components (MW < 1,000) based on professional judgment. The higher MW components of this polymer
(MW >1,000) are expected to have limited bioavailability and have low potential for reproductive toxicity.
There is potential for reproductive
toxicity based on a structural alert for
epoxy groups/epoxides.
(Estimated)
There is potential for male reproductive
toxicity for the low MW components.
(Estimated)
Estimated to have a low potential for
Professional judgment; EPA,
2010
Professional judgment
Boethling and Nabholz, 1997;
^o data located.
No data located.
No data located.
Estimated based on a structural alert
for epoxy groups/epoxides and
professional judgment.
Estimated for the low MW
components based on professional
ludgment.
Estimated for the high MW
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PROPERTY/ENDPOINT
Developmental Effects
Reproduction/
Developmental Toxicity
Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Prenatal Development
Postnatal Development
Prenatal and Postnatal
Development
Developmental Neurotoxicity
Other
DATA
reproductive effects for the high MW
component. Limited bioavailability
expected.
(Estimated)
REFERENCE
Professional judgment
DATA QUALITY
component (MW >1,000) based on
professional judgment and the cutoff
value for large, high MW non-ionic
polymer components.
MODERATE: There is an estimated potential for developmental toxicity based on a structural alert for
epoxy groups/epoxides and an estimated potential for developmental toxicity for the low MW components
(MW < 1,000) based on professional judgment. The higher MW components of this polymer (MW >1,000)
are expected to have limited bioavailability and have low potential for developmental toxicity.
There is uncertain concern for developmental neurotoxicity based on the potential for cholinesterase
(ChE) inhibition in dams that may result in alterations of fetal neurodevelopment. No experimental data
were located for this substance.
Uncertain concern for developmental
neurotoxicity based on the potential for
cholinesterase (ChE) inhibition in dams
that may result in alterations of fetal
neurodevelopment.
There is potential for developmental
toxicity based on a structural alert for
epoxy groups/epoxides.
(Estimated)
Estimated to have a low potential for
developmental effects for the high MW
component. Limited bioavailability
Professional judgment
Professional judgment; EPA,
2012
Boethling and Nabholz, 1997;
Professional judgment
^o data located.
No data located.
No data located.
No data located.
No data located.
Estimated based on a structural alert
for organophosphates for the
neurotoxicity endpoint.
Estimated based on a structural alert
for epoxy groups/epoxides and
srofessional judgment.
Estimated for the high MW
component (MW >1,000) based on
srofessional judgment and the cutoff
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
expected.
(Estimated)
value for large, high MW non-ionic
polymer components.
Neurotoxicity
MODERATE: There is an estimated potential for neurotoxicity based on a structural alert for
organophosphorus compounds and professional judgment. The higher MW components of this polymer
(MW >1,000) are expected to have limited bioavailability and have low potential for neurotoxicity. There
were no experimental data located for this substance.
Neurotoxicity Screening
Battery (Adult)
Other
There is potential for neurotoxicity based
on the structural alert of
organophosphorus compounds.
(Estimated)
Estimated to have a low potential for
neurotoxicity for the high MW
component. Limited bioavailability
expected.
(Estimated)
Professional judgment; EPA,
2012
Boethling and Nabholz, 1997;
Professional judgment
data located.
Estimated based on a structural alert
for organophosphorus compounds
and professional judgment.
Estimated for the high MW
Component (MW >1,000) based on
srofessional judgment and the cutoff
value for large, high MW non-ionic
3olymer components.
Repeated Dose Effects
MODERATE: There is an estimated potential for repeated dose effects for the low MW components
(<1,000) for the inhalation and dermal routes of exposure. Experimental data for the analog DOPO
(CASRN 35948-25-5) indicated a Low hazard designation with a reported NOAEL of 1,023 mg/kg-day
(highest dose tested) in a 16-week dietary study in rats. The higher MW components of this polymer (MW
>1,000) are expected to have limited bioavailability and have low potential for repeated dose effects. There
were no experimental data located for this substance.
There is potential for repeated dose
effects for the low MW component for
the inhalation and dermal routes of
exposure.
Male and female Wistar rats
(20/sex/dose) were fed diets containing 0,
0.24, 0.6, or 1.5%HCA (0, 159, 399, or
1,023 mg HCA/kg-day to males; 0, 177,
445, or 1,094 mg HCA/kg-day to
females) of the analog DOPO for 16
weeks (purity of test substance not
Professional judgment
Estimated for the low MW
component based on professional
judgment.
ECHA, 2013; Professional
judgment
Estimated based on analogy to
DOPO (CASRN 35948-25-5).
Sufficient information in secondary
source; data lacking regarding
detailed clinical observations and
neurobehavioral examination. Study
equivalent to OECD guideline 408.
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PROPERTY/ENDPOINT
Skin Sensitization
Skin Sensitization
Respiratory Sensitization
Respiratory Sensitization
DATA
provided).
There were no significant effects on body
weight, food consumption, hematology,
limited clinical chemistry, urinalysis,
organ weight, and gross and microscopic
examination of major organs.
NOAEL: 1,023 mg/kg-day (males), 1,094
mg/kg-day (females); highest dose tested
LOAEL: Not established
(Estimated based on analogy)
Estimated to have a low potential for
repeated dose effects for the high MW
component. Limited bioavailability
expected.
(Estimated)
REFERENCE
Boethling and Nabholz, 1997;
Professional judgment
DATA QUALITY
Study pre-dates GLP. Test substance
identified as HCA in study report.
Primary reference not identified.
Estimated for the high MW
component (MW >1,000) based on
professional judgment and the cutoff
value for large, high MW non-ionic
polymer components.
HIGH: Positive for skin Sensitization in guinea pigs; reported in a submitted confidential study for the low
MW components (MW < 1,000). In addition, there is an estimated potential for skin Sensitization based on
a structural alert for epoxy groups/epoxides.
Sensitizing, guinea pigs
Positive for skin Sensitization for the low
MW component.
There is potential for skin Sensitization
based on a structural alert for epoxy
groups/epoxides.
(Estimated)
Submitted confidential study
Submitted confidential study
Professional judgment; EPA,
2012
Data reported in a submitted
confidential study.
Data reported in a submitted
confidential study for the low MW
component.
Estimated based on a structural alert
for epoxy groups/epoxides and
professional judgment.
MODERATE: There is an estimated potential for respiratory Sensitization for the low MW component
(MW < 1,000) based on professional judgment.
There is potential for respiratory
Sensitization for the low MW component.
(Estimated)
OSHA, 1999; Professional
judgment
Estimated based presence of
epoxides and professional judgment
for the low MW component.
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PROPERTY/ENDPOINT
Eye Irritation
Eye Irritation
Dermal Irritation
Dermal Irritation
Endocrine Activity
Immunotoxicity
Immune System Effects
DATA
REFERENCE
DATA QUALITY
VERY LOW: Based on a submitted confidential study, the polymer did not produce eye irritation in
rabbits.
Negative, rabbits
Submitted confidential study
Limited study details reported in a
confidential study.
LOW: Negative for skin irritation in rabbits reported in a submitted confidential study. One study
reported positive results for skin irritation, but did not contain adequate study details for assessment.
Positive for skin irritation for the low
MW component.
Negative, rabbits
Submitted confidential study
Submitted confidential study
Inadequate study details reported in
a submitted confidential study for
the low MW component.
Data reported in a submitted
confidential study.
No data located.
|No data located.
Estimated to have a low potential for immunotoxic effects based on expert judgment. The higher MW
components of this polymer (MW >1,000) are expected to have limited bioavailability and have low
potential for immunotoxicity.
Low potential for immunotoxic effects
for the low MW component.
(Estimated)
Estimated to have a low potential for
immunotoxic effects for the high MW
component. Limited bioavailability
expected.
Expert judgment
Boethling and Nabholz, 1997;
Professional judgment
Estimated based on expert judgment.
Estimated for the high MW
component (MW >1,000) based on
professional judgment.
ECOTOXICITY
ECOSAR Class
Acute Aquatic Toxicity
Fish LC50
Epoxides, mono; Esters (Phosphinates)
LOW: Based on estimated acute aquatic toxicity values for fish, daphnia, and green algae, which all exceed
the water solubility. No Effects at Saturation (NES) are predicted for these endpoints.
NES
(Estimated)
Freshwater fish 96-hour LC50:
Professional judgment
ECOSAR v 1.11
Estimations for the oligomers with a
high MW; limited bioavailability
and low water solubility suggest
there will be NES.
Estimations for confidential
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
1.7 mg/L (ECOSAR class: Esters,
phosphinate);
10.4 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
Freshwater fish 96-hour LC50:
0.87 mg/L (ECOSAR class: Epoxides,
mono);
0.74 mg/L (ECOSAR class: Esters
phosphinates);
0.49 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
Freshwater fish 14-day LC50:
0.13 mg/L (ECOSAR class: Epoxides,
poly);
Freshwater fish 96-hour LC50: 0.28 mg/L
(ECOSAR class: Esters phosphinates);
ECOSAR v 1.11
representative structure 1. The
estimated values exceed the water
solubility (0.62 mg/L). The chemical
may not be soluble enough to
measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 2. NES: The
log Kow of 5.3 for this chemical
exceeds the SAR limitation for the
log Kow of 5.0; NES are predicted
for these endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 3. NES: The
log Kow of 6.9 for this chemical
exceeds the SAR limitation for the
log Kow of 5.0 or 6.0; NES are
predicted for these endpoints.
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Freshwater fish 96-hour LC50: 0.021
mg/L (ECOSAR class: Neutral organic
SAR)
(Estimated)
Freshwater fish 96-hour LC50:
1.7 mg/L (ECOSAR class: Epoxides,
mono);
1.1 mg/L (ECOSAR class: Esters
phosphinates);
1.5 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 4. The
estimated values exceed the water
solubility (0.0082 mg/L). The
chemical may not be soluble enough
to measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Daphnid LC50
NES
(Estimated)
Professional judgment
Daphnid 48-hour LC50:
1.2 mg/L (ECOSAR class: Esters,
phosphinate);
6.9 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
Estimations for the oligomers with a
high MW; limited bioavailability
and low water solubility suggest
there will be NES.
Estimations for confidential
representative structure 1. The
estimated values exceed the water
solubility (0.62 mg/L). The chemical
may not be soluble enough to
measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Daphnid 48-hour LC50:
0.69 mg/L (ECOSAR class: Epoxides,
mono);
0.56 mg/L (ECOSAR class: Esters
phosphinates);
0.38 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
Daphnid 48-hour LC50:
0.071 mg/L (ECOSAR class: Epoxides,
poly);
0.24 mg/L (ECOSAR class: Esters
phosphinates);
0.019 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 2. The log
Kow of 5.3 for this chemical exceeds
the SAR limitation for the log Kow
of 5.0; NES are predicted for these
endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 3. NES: The
log Kow of 6.9 for this chemical
exceeds the SAR limitation for the
log Kow of 5.0; NES are predicted
for these endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
4-201
-------
Dow XZ-92547
PROPERTY/ENDPOINT
Green Algae EC50
DATA
Daphnid 48-hour LC50:
1.6 mg/L (ECOSAR class: Epoxides,
mono);
0.78 mg/L (ECOSAR class: Esters
phosphinates);
1.1 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
NES
(Estimated)
Green algae 96-hour EC50:
9.6 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
Green algae 96-hour EC50:
0.34 mg/L (ECOSAR class: Epoxides,
REFERENCE
ECOSAR v 1.11
Professional judgment
ECOSAR v 1.11
ECOSAR v 1.11
DATA QUALITY
Estimations for confidential
representative structure 4. The
estimated values exceed the water
solubility (0.0082 mg/L). The
chemical may not be soluble enough
to measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for the oligomers with a
high MW; limited bioavailability
and low water solubility suggest
there will be NES.
Estimations for confidential
representative structure 1 . The
estimated value exceeds the water
solubility (0.62 mg/L). The chemical
may not be soluble enough to
measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 2. The
4-202
-------
Dow XZ-92547
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
mono);
0.99 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
Green algae 96-hour EC50: 0.093 mg/L
(ECOSAR class: Neutral organic SAR)
(Estimated)
ECOSAR v 1.11
Green algae 96-hour EC50:
0.9 mg/L (ECOSAR class: Epoxides,
mono);
2.3 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
estimated values exceed the water
solubility (0.0023 mg/L). The
chemical may not be soluble enough
to measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 3. NES: The
log Kow of 6.9 for this chemical
exceeds the SAR limitation for the
log Kow of 6.4; NES are predicted
for these endpoints.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 4. The
estimated values exceed the water
solubility (0.0082 mg/L). The
chemical may not be soluble enough
to measure the predicted effect.
Narcosis classes (neutral organics)
4-203
-------
Dow XZ-92547
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Chronic Aquatic Toxicity
HIGH: Based on estimated chronic aquatic toxicity values for the confidential representative structures 1
and 4 for fish and daphnia.
Fish ChV
NES
(Estimated)
Freshwater fish ChV:
0.041 mg/L (ECOSAR class: Esters,
phosphinate);
1.2 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
Freshwater fish ChV:
0.003 mg/L (ECOSAR class: Epoxides,
mono);
0.008 mg/L (ECOSAR class: Esters
phosphinates);
0.069 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
Professional judgment
ECOSAR v 1.11
ECOSAR v 1.11
Estimations for the oligomers with a
high MW; limited bioavailability
and low water solubility suggest
there will be NES.
Estimations for confidential
representative structure 1.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 2. The
estimated values exceed the water
solubility (0.0023 mg/L). The
chemical may not be soluble enough
to measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
4-204
-------
Dow XZ-92547
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Freshwater fish ChV:
0.0014 mg/L (ECOSAR class: Epoxides,
poly);
0.0016 mg/L (ECOSAR class: Esters
phosphinates);
0.004 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
Freshwater fish ChV:
0.004 mg/L (ECOSAR class: epoxides,
mono);
0.02 mg/L (ECOSAR class: Esters
phosphinates);
0.20 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 3. The
estimated values exceed the water
solubility (7.7xlO~6). The chemical
may not be soluble enough to
measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 4.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Daphnid ChV
NES
(Estimated)
Professional judgment
Daphnid ChV:
0.042 mg/L (ECOSAR class: Esters,
4-205
ECOSAR v 1.11
Estimations for the oligomers with a
high MW; limited bioavailability
and low water solubility suggest
there will be NES.
Estimations for confidential
representative structure 1.
-------
Dow XZ-92547
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
phosphinate);
1.03 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
Daphnia ChV:
0.064 mg/L (ECOSAR class: Epoxides,
mono);
0.012 mg/L (ECOSAR class: Esters
phosphinates);
0.086 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
Daphnid ChV:
0.005 mg/L (ECOSAR class: Epoxides,
poly);
0.003 mg/L (ECOSAR class: Esters
phosphinates);
0.007 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 2. The
estimated values exceed the water
solubility (0.0023 mg/L). The
chemical may not be soluble enough
to measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 3. The
estimated values exceed the water
solubility (7.7xlO~6). The chemical
may not be soluble enough to
measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
4-206
-------
Dow XZ-92547
PROPERTY/ENDPOINT
Green Algae ChV
DATA
Daphnid ChV:
0.15 mg/L (ECOSAR class: Epoxides,
mono);
0.02 mg/L (ECOSAR class: Esters
phosphinates):
0.22 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
NES
(Estimated)
Green algae ChV: 3.6 mg/L (ECOSAR
class: Neutral organic SAR)
(Estimated)
Green algae ChV:
0.69 mg/L (ECOSAR class: Epoxides,
mono);
REFERENCE
ECOSAR v 1.11
Professional judgment
ECOSAR v 1.11
ECOSAR v 1.11
DATA QUALITY
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 4.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for the oligomers with a
high MW; limited bioavailability
and low water solubility suggest
there will be NES.
Estimations for confidential
representative structure 1 . The
estimated values exceed the water
solubility (0.62 mg/L). The chemical
may not be soluble enough to
measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 2. The
estimated values exceed the water
4-207
-------
Dow XZ-92547
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
0.51 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
Green algae ChV: 0.068 mg/L (ECOSAR
class: Neutral organic SAR)
(Estimated)
ECOSAR v 1.11
Green algae ChV:
1.5 mg/L (ECOSAR class: Epoxides,
mono);
1.0 mg/L (ECOSAR class: Neutral
organic SAR)
(Estimated)
ECOSAR v 1.11
solubility (0.0023 mg/L). The
chemical may not be soluble enough
to measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 3. The
estimated value exceeds the water
solubility (7.7xlO~6). The chemical
may not be soluble enough to
measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
Estimations for confidential
representative structure 4. The
estimated values exceed the water
solubility (0.0082 mg/L). The
chemical may not be soluble enough
to measure the predicted effect.
Narcosis classes (neutral organics)
are provided for comparative
4-208
-------
Dow XZ-92547
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
purposes; DfE assessment
methodology will use the lowest
estimated toxicity value provided by
ECOSAR classes that have a more
specific mode of action relative to
narcosis.
ENVIRONMENTAL FATE
Transport
Henry's Law Constant (atm-
m3/mole)
Sediment/Soil
Adsorption/Desorption - Koc
The estimated negligible water solubility and estimated negligible vapor pressure indicate that this
polymer, including the low MW and high MW components, is anticipated to partition predominantly to
soil. The estimated Henry's Law Constant of <10~8 atm-m3/mole indicates that it is not expected to
volatilize from water to the atmosphere. Although estimates for one confidential representative structure
results in a moderate absorption coefficient of 1,596, the estimated Koc of >30,000 for the high MW
components and 3 other confidential representative substances indicate that the majority of this polymeric
mixture is not anticipated to migrate from soil into groundwater and also has the potential to adsorb to
sediment.
<10"8 Bond SAR Method (Estimated)
<10"8 (Estimated)
1,595 (Estimated)
>3 0,000 (Estimated)
>3 0,000 (Estimated)
EPI v4.1 1; Professional
judgment
Boethling and Nabholz, 1997;
Professional judgment
EPI v4. 11; Professional
judgment
EPI v4. 11; EPA, 1999
Boethling and Nabholz, 1997;
Professional judgment
Estimated value based on four
confidential representative structures
with MW <1,000. Cutoff value for
nonvolatile compounds.
Estimated for the MW > 1,000
oligomers. High MW polymers are
expected to have low vapor pressure
and are not expected to undergo
volatilization.
Estimate based on confidential
representative structure 1 .
Estimated values for confidential
representative structures 2, 3 and 4.
Cutoff value fornonmobile
compounds according to HPV
assessment guidance.
Estimated for the oligomers with
MW > 1,000; cutoff value used for
large, high MW polymers. High
4-209
-------
Dow XZ-92547
PROPERTY/ENDPOINT
Level III Fugacity Model
Persistence
Water
Soil
Aerobic Biodegradation
Volatilization Half-life for
Model River
Volatilization Half-life for
Model Lake
Aerobic Biodegradation
Anaerobic Biodegradation
DATA
Air = 0%
Water = 12%
Soil = 88%
Sediment =1% (Estimated)
REFERENCE
EPIv4.11
DATA QUALITY
MW polymers are expected to
adsorb strongly to soil and sediment.
Estimates based on confidential
representative structure 1 . No data
located for the high MW component
of the polymers.
VERY HIGH: The persistence designation for this polymer is based on its higher MW components (MW
>1,000). The higher MW components are expected to have Very High persistence because of their low
water solubility and poor bioavailability, indicating that neither biodegradation nor hydrolysis are
expected to be important environmental fate processes. The lower MW oligomers (MW <1,000) of this
polymer have higher estimated water solubility and increased bioavailability to microorganisms and
therefore would be expected to have lower persistence. This polymer does not contain functional groups
that would be expected to absorb light at environmentally significant wavelengths. Evaluation of these
degradation values suggest a half-life of >180 days.
Days-weeks (Primary Survey Model)
Weeks-months (Ultimate Survey Model)
(Estimated)
Recalcitrant
for MW >1,000 components (Estimated)
>1 year (Estimated)
>1 year (Estimated)
Recalcitrant
for MW >1,000 components (Estimated)
EPIv4.11
Professional judgment;
Boethling and Nabholz, 1997
EPIv4. 11; Professional
judgment
EPI v4.1 1; Professional
judgment
Professional judgment;
Boethling and Nabholz, 1997
Estimates based on confidential
representative structure 1 .
High MW polymers are expected to
3e non-biodegradable.
Estimated value based on four
confidential representative structures
with MW < 1,000; the high MW
polymer components are anticipated
to be nonvolatile.
Estimated value based on four
confidential representative structures
with MW < 1,000; the high MW
3olymer components are anticipated
to be nonvolatile.
^o data located.
High MW polymers are expected to
3e resistant to removal under anoxic
conditions due to their limited
sioavailability.
4-210
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Dow XZ-92547
PROPERTY/ENDPOINT
Air
Reactivity
Soil Biodegradation with
Product Identification
Sediment/Water
Biodegradation
Atmospheric Half-life
Photolysis
Hydrolysis
Environmental Half-life
DATA
<0. 19 days (Estimated)
Not a significant fate process (Estimated)
50%/>1 month (Estimated)
50%/>1 year (Estimated)
75 days in soil (Estimated)
REFERENCE
EPIv4.11
Professional judgment; Mill,
2000
Professional judgment
EPIv4.11
PBT Profiler vl.301; EPI v4.11
DATA QUALITY
No data located.
^o data located.
Estimated value based on four
confidential representative structures
withMW
-------
Dow XZ-92547
PROPERTY/ENDPOINT
Bioaccumulation
Fish BCF
Other BCF
BAF
DATA
REFERENCE
DATA QUALITY
HIGH: The bioaccumulation designation is based on the estimated BCF and BAF values >1,000; these
values are estimated using confidential representative structures of lower MW components (MW <1,000)
of Dow XZ-92547. The higher MW oligomers that may be found in this mixture are expected to have low
potential for bioaccumulation based on their large size and low solubility according to polymer assessment
literature.
9,900 (Estimated)
610 (Estimated)
820 (Estimated)
68 (Estimated)
<100 (Estimated)
620 (Estimated)
2,300 (Estimated)
600 (Estimated)
180 (Estimated)
EPIv4.11
EPIv4.11
EPIv4.11
EPIv4.11
Professional judgment
EPIv4.11
EPIv4.11
EPIv4.11
EPIv4.11
Estimates based on confidential
representative structure 3 with MW
<1,000.
Estimates based on confidential
representative structure 4 with MW
<1,000.
Estimates based on confidential
representative structure 2 with MW
<1,000.
Estimates based on confidential
representative structure 1 with MW
<1,000.
Estimated for the oligomers with a
MW >1,000. Cutoff value for large,
ligh MW, insoluble polymers.
No data located.
Estimates based on confidential
representative structure 4 with MW
<1,000.
Estimates based on confidential
representative structure 3 with MW
<1,000.
Estimates based on confidential
representative structure 2 with MW
<1,000.
Estimates based on confidential
representative structure 1 with MW
<1,000.
4-212
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Dow XZ-92547
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Metabolism in Fish
No data located.
ENVIRONMENTAL MONITORING AND BIOMONITORING
Environmental Monitoring
No data located.
Ecological Biomonitoring
No data located.
Human Biomonitoring
This chemical was not included in the NHANES biomonitoring report (CDC, 2013).
4-213
-------
Boethling RS and Nabholz JV (1997) Environmental assessment of polymers under the U.S. Toxic Substances Control Act. Washington, DC: U.S.
Environmental Protection Agency.
CDC (2013) Fourth national report on human exposure to environmental chemicals, updated tables, March 2013.
http://www.cdc.gov/exposurereport/pdf/FourthReport_UpdatedTables_Mar2013.pdf.
ECHA (2013) 6H-dibenz[c,e][l,2]oxaphosphorin 6-oxide. Registered substances. European Chemicals Agency.
http://apps.echa.europa.eu/registered/data/dossiers/DISS-db99cff9-92de-Odla-e044-00144f67d031/DISS-db99cff9-92de-Odla-e044-
00144f67d031_DISS-db99cff9-92de-Odla-e044-00144f67d031.html.
ECOSAR Ecological Structure Activity Relationship (ECOSAR). Estimation Programs Interface (EPI) Suite for Windows, Version 1.11.
Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency, http://www.epa.gov/oppt/newchems/tools/21ecosar.htm.
EPA (1999) Determining the adequacy of existing data. High Production Volume (HPV) Challenge. Washington, DC: U.S. Environmental
Protection Agency, http://www.epa.gov/hpv/pubs/general/datadeqfn.pdf
EPA (2010) TSCA new chemicals program (NCP) chemical categories. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/newchems/pubs/npcchemicalcategories.pdf
EPA (2012) Using noncancer screening within the SF initiative. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/sf/pubs/noncan-screen.htm.
EPI Estimation Programs Interface (EPI) Suite, Version 4.11. Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency.
http://www.epa.gov/opptintr/exposure/pubs/episuitedl.htm.
ESIS (2012) European chemical Substances Information System. European Commission, http://esis.jrc.ec.europa.eu/.
Mill T (2000) Photoreactions in surface waters. In: Boethling R, Mackay D, eds. Handbook of Property Estimation Methods for Chemicals,
Environmental Health Sciences. Boca Raton: Lewis Publishers.:355-381.
OSHA (1999) Polymer matrix materials Advanced composites. OSHA Technical Manual (OTM) Section III: Chapter 1.
https://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_l.html.
PBT Profiler Persistent (P), Bioaccumulative (B), and Toxic (T) Chemical (PBT) Profiler, Version 1.301. Washington, DC: U.S. Environmental
Protection Agency, www.pbtprofiler.net.
4-214
-------
Aluminum Diethylphosphinate
VL = Very Low hazard L = Low hazard = Moderate hazard H = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion
by-products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the
table.
§ Based on analogy to experimental data for a structurally similar compound. R Recalcitrant: Substance is comprised of metallic species (or metalloids) that will not degrade, but may
change oxidation state or undergo complexation processes under environmental conditions. ¥ Aquatic toxicity: EPA/DfE criteria are based in large part upon water column exposures
which may not be adequate for poorly soluble substances such as many flame retardants that may partition to sediment and particulates.
Chemical
CASRN
Human Health Effects
Acute Toxicity
Carcinogenicil
Genotoxicity
Reproductive
Developmenta
Neurological
Repeated Dost
.0
Skin Sensitizal
Respiratory
Sensitization
.0
"3
hH
0)
W
a
o
Dermal Irritat
Aquatic
Toxicity
1
Chronic
Environmental
Fate
Persistence
a
O
Bioaccumulati
Aluminum Diethylphosphinate
225789-38-8
VL
HR
4-215
-------
Aluminum Diethylphosphinate
vJ_v
\_p^
Cf
A!3*
A ^o" ox r
-p P-
) (
CASRN: 225789-38-8
MW: 390.27
MF: 3 C4HnPO2 Al
Physical Forms:
Neat: Solid
Use: Flame retardant
SMILES: CCP(=O)(CC)O[A1](OP(=O)(CC)CC)OP(=O)(CC)CC
Synonyms: Exolit OP 930, Aluminium diethylphosphinate, Aluminium tris(diethylphosphinate)
Chemical Considerations: This alternative is an inorganic compound and in the absence of experimental data, professional judgment using chemical class and
structural considerations were used to complete this hazard profile.
Polymeric: No
Oligomeric: Not applicable
Metabolites, Degradates and Transformation Products: Aluminum and diethylphosphinic acid may dissociate (Australia, 2005)
Analog: Confidential aluminum metal salts; aluminum hydroxide; phosphate
esters
Endpoint(s) using analog values: Absorption, distribution, metabolism &
excretion, carcinogenicity, developmental toxicity, immunotoxicity,
neurotoxicity, repeated dose effects
Structural Alerts: Not applicable
Analog Structure: Not applicable
Risk Phrases: Not classified by Annex VI Regulation (EC) No 1272/2008 (ESIS, 201 1).
Hazard and Risk Assessments: Hazard assessment in Design for the Environment Alternatives Assessment for Flame Retardants in Printed Circuit Boards, Review
Draft, November 8, 2008 (EPA, 2008).
4-216
-------
Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
Water Solubility (mg/L)
Decomposes at 315 (Measured)
Decomposes at 300 (Measured)
>400 according to EU Method A. 1 using
differential scanning calorimetry
(Measured)
Decomposes at 330 (Measured)
Decomposes at > 300 (Measured)
>400 (Measured)
Expected to decompose before boiling
(Estimated)
<10"8 (Estimated)
2.5xl03 (Measured)
<1
Submitted confidential study
Submitted confidential study
ECHA, 20 13; Submitted
confidential study
DeBoysere and Dietz, 2005
Clariant, 2007
Australia, 2005
Professional judgment
EPA, 1999; Professional
judgment
Submitted confidential study
ECHA, 20 13; Submitted
Adequate.
Adequate.
Adequate.
Sufficient details were not available
to assess the quality of this study.
Sufficient details were not available
to assess the quality of this study.
Sufficient details were not available
to assess the quality of this study.
Reported for a commercial
formulation.
Based on available data for melting
point.
Cutoff value for nonvolatile
compounds according to HPV
assessment guidance.
Sufficient details were not available
to assess the quality of this study.
Aluminum diethylphosphinate has
low wettability and very slow
dissolution. This gives a kinetically
controlled solubility of <1 mg/L by
guideline 92/69/EEC A.6. If
aluminum diethylphosphinate is
formed by precipitation of a soluble
salt, the remaining equilibrium
solubility of 2.5x 103 mg/L is found.
This can be assumed to be the true
limit of solubility under ideal
conditions.
Guideline study; aluminum
4-217
-------
Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
Log Kow
Flammability (Flash Point)
Explosivity
Pyrolysis
DATA
According to EU Method A. 6 (Measured)
<1
According to EU Method A. 6 (Measured)
-0.44
(Estimated)
No self-ignition below 402°C (Measured)
Not readily combustible according to
guideline 96/69/EEC, test A. 10.
(Measured)
Not expected to form explosive mixtures
with air (Estimated)
Major products are diethylphosphinic
acid, ethylphosphonic acid, phosphoric
acid, and their respective salts
(Measured)
REFERENCE
confidential study
Australia, 2005; Submitted
confidential study
Beard and Marzi, 2005; Stuer-
Lauridsen et al., 2007
ECHA, 20 13; Submitted
confidential study
Submitted confidential study
Professional judgment
Beard and Marzi, 2005
DATA QUALITY
diethylphosphinate has low
wettability and very slow
dissolution. If aluminum
diethylphosphinate is formed by
precipitation of a soluble salt, the
remaining equilibrium solubility of
2.5 x 103 mg/L is found, which can be
assumed to be the true limit of
solubility under ideal conditions.
Reported in a secondary source for a
commercial formulation.
Reported in a secondary source with
limited study details; it is unclear
whether this value reflects the
chemical's low water solubility or its
lipophobicity.
Adequate.
Guideline study.
No data located; based on its use as a
flame retardant.
Study details and test conditions
were not available.
4-218
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
pH
pKa
Particle Size
DATA
pH of an aqueous suspension was 4.0;
aluminum diethylphosphinate completely
dissociated within 24 hours at pH 4.5
during Japanese Ministry of International
Trade and Industry (MITI) test.
(Measured)
DIG = mean ca. 0.4 < 2 (im
D50 = mean ca. 0.4 < 29 (im
According to Laser-Diffraction method.
(Estimated)
REFERENCE
Beard and Marzi, 2005;
Australia, 2005
ECHA, 2013
DATA QUALITY
Inadequate. Although this compound
does not contain acidic protons, the
reference indicates that the acidity
results from equilibria involving the
dissociated species in solution. Study
details and test conditions were not
available. Available data for
commercial formulations suggest
that this compound is likely to
dissociate under environmental
conditions. However, dissociation is
expected to vary as a function of pH
to a degree that will have a
significant influence on its
environmental fate. Available data
are not adequate to assess its
dissociation under typical
environmental conditions.
No data located.
Nonguideline study reported in a
secondary source.
4-219
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
HUMAN HEALTH EFFECTS
Toxicokinetics
Dermal Absorption in vitro
Absorption,
Distribution,
Metabolism &
Excretion
Oral, Dermal or Inhaled
Other
Acute Mammalian Toxicity
Based on estimates of physical and chemical properties, analogs, and professional judgment, aluminum
diethylphosphinate is determined to not be readily absorbed through skin but may be absorbed through
the inhalation of dust and oral exposure. Absorption is estimated to be good through the gastrointestinal
tract based on physical/chemical properties and analogs; however, only a small amount of administered
dose was reported to be absorbed in the gastrointestinal tract in a submitted confidential rat study.
Elimination was reported primarily in the feces in a confidential study, while in contrast, elimination was
reported to occur primarily in the urine within 12 hours of oral administration in another study.
Absorption as neat solid expected to be
negligible through skin. Absorption good
through lungs. Absorption good through
gastrointestinal tract. (Estimated)
Following oral administration, excretion
was almost quantitative via the urine
within 12 hours.
Male rats (2/dose group) administered
(unradiolabeled) test substance via single
oral gavage at 180 and 1,000 mg/kg-day.
Only a small amount of the administered
dose was absorbed by the gastro-
intestinal tract. The major route of
elimination was in the feces (unabsorbed
fraction) and a small amount of free test
substance was detected in the urine. After
36 hours, no test substance was detected.
Professional judgment
Stuer-Lauridsen et al., 2007
Submitted confidential study
Estimates based on
physical/chemical properties and
confidential analogs.
Study details reported in a secondary
source
Study details from an abstract
reported in a confidential
submission; study conducted
according to OECD 417; small
number of animals tested.
No data located.
LOW: Experimental studies indicate that oral and dermal routes to rats do not produce mortality at oral
and dermal doses up to 2,000 mg/kg. No lethality data was located for inhalation exposure.
4-220
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
Acute Lethality
Oral
Dermal
Inhalation
Carcinogenicity
OncoLogic Results
Carcinogenicity (Rat and
Mouse)
Combined Chronic
Toxicity/Carcinogenicity
Other
Genotoxicity
Gene Mutation in vitro
Gene Mutation in vivo
Chromosomal Aberrations in
vitro
DATA
Rat oral LD50 >2,000 mg/kg
Rat dermal LD50 >2,000 mg/kg
REFERENCE
Australia, 2005; Submitted
confidential study
Australia, 2005; Submitted
confidential study
DATA QUALITY
Reported in a secondary source for a
commercial formulation. Test
substance was Exolit OP 930.
Conducted according to OECD TG
401.
Reported in a secondary source for a
commercial formulation. Test
substance was Exolit OP 930.
Conducted according to OECD TG
402.
No data located.
LOW: Aluminum diethylphosphinate is estimated to be of low hazard for Carcinogenicity based on
comparison to analogous metal salts and professional judgment.
Not expected to be carcinogenic.
(Estimated)
Professional judgment
No data located.
Estimated based on analogy to
confidential metal salts.
No data located.
No data located.
LOW: Experimental studies indicate that aluminum diethylphosphinate does not cause gene mutations in
bacteria or chromosomal aberrations in mammalian cells.
Negative, Salmonella typhimurium
strains TA1535, TA1537, TA1538, TA98
and TA100 with and without metabolic
activation
Negative, chromosomal aberrations in
Chinese hamster lung cells with and
without metabolic activation
Australia, 2005; Stuer-Lauridsen
et al., 2007; Submitted
confidential study
Australia, 2005; Submitted
confidential study
Reported in a secondary source for a
commercial formulation. Conducted
according to OECD TG 471.
No data located.
Reported in a secondary source for a
commercial formulation. Conducted
according to OECD TG 473.
4-221
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Chromosomal Aberrations in
vivo
Negative, mammalian erythrocyte
micronucleus test in NMRI mice; oral
(unspecified)
Submitted confidential study
Study reported in a submitted
confidential study; Study conducted
according to OECD Guideline 474
(Mammalian Erythrocyte
Micronucleus Test).
DNA Damage and Repair
No data located.
Other
No data located.
Reproductive Effects
LOW: Changes (characterized as minor) in the number of days of pre-coital interval and a reduction in
copulation plugs were reported in a submitted confidential study at 1,000 mg/kg-day. The study-reported
NOAEL is on the margin of the Low to Very Low hazard designation; therefore a Low hazard designation
was assigned. Aluminum diethylphosphinate is also estimated to be of low hazard for reproductive effects
based on professional judgment and comparison to analogous metal salts.
Reproduction/Developmental
Toxicity Screen
Expected to have low hazard potential for
reproductive effects. (Estimated)
Rats (Sprague Dawley); oral
administration of 250 and 1,000 mg/kg
bw-day; 15 days prior to mating and
throughout gestation and lactation up to
post-partum Day 3.
Parental effects: No clinical signs of
toxicity or change in food consumption.
Slight reduction in body weight and body
weight gain (both sexes, 1,000 mg/kg-
day); Reduced terminal body weight and
absolute and relative kidney weights
(males, 1,000 mg/kg-day).
No adverse effect on oestrus cycle,
implantation, gestation length, corpora
lutea or sex ratios. No effect on sperm
(motility, morphology, concentration).
Increase in the number of days of pre-
coital interval and a reduction in
copulation plugs (1,000 mg/kg-day);
Professional judgment
Submitted confidential study
Estimated based on analogy to
confidential metal salts.
Study reported in a submitted
confidential study; Study conducted
according to OECD Guideline 421
(Reproductive/Developmental
Toxicity Screening Test).
4-222
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
these changes were reported as "minor"
No treatment-related macroscopic
anomalies in pups dying or sacrificed at
term.
NOAEL: 1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
No data located.
Reproduction and Fertility
Effects
No data located.
Other
No data located.
Developmental Effects
MODERATE: There were no developmental effects reported in a reproduction/developmental toxicity
screen in rats at doses up to 1,000 mg/kg-day. There is moderate hazard for aluminum diethylphosphinate
given exposure may result in neurodevelopmental effects based on the presence of a phosphinate; there
were no experimental studies specifically designed to evaluate the neurodevelopmental endpoint located.
The potential for neurodevelopmental effects cannot be ruled out.
Reproduction/
Developmental Toxicity
Screen
Expected to have a moderate hazard
potential for developmental and
neurodevelopmental effects resulting
from the presence of a phosphinate.
(Estimated)
Rats (Sprague Dawley); oral
administration of 250 and 1,000 mg/kg
bw-day; 15 days prior to mating and
throughout gestation and lactation up to
post-partum Day 3.
Parental: No clinical signs of toxicity or
change in food consumption. Slight
reduction in body weight and body
4-223
Professional judgment
Submitted confidential study
Estimated based on analogy to
phosphate esters and associated
cholinesterase inhibition.
Study details reported in a
confidential submission; Study
conducted according to OECD
Guideline 421
(Reproductive/Developmental
Toxicity Screening Test).
-------
Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Prenatal Development
Postnatal Development
Prenatal and Postnatal
Development
Developmental Neurotoxicity
Other
DATA
weight gain; reduced terminal body
weight and absolute and relative kidney
weights (males, 1,000 mg/kg-day). No
adverse effect on estrus cycle,
implantation, gestation length, corpora
lutea or sex ratios. No effect on sperm
(motility, morphology, concentration).
Increase in the number of days of pre-
coital interval and a reduction in
copulation plugs (1,000 mg/kg-day).
No treatment-related macroscopic
anomalies in pups dying or sacrificed at
term.
NOAEL = 1,000 mg/kg-day
REFERENCE
DATA QUALITY
No data located.
No data located.
No data located.
No data located.
No data located.
No data located.
4-224
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Neurotoxicity
MODERATE: Aluminum diethylphosphinate is expected to be of Moderate hazard for based on analogy
to aluminum hydroxide and professional judgment. Exposure to the analog resulted in impaired learning
in a labyrinth maze test in a 90-day oral study in rats at 35 mg Al/kg/day as aluminum hydroxide with
citric acid. Impaired learning in a labyrinth maze test was also reported in rats orally exposed to 300 mg
Al/kg/day (only dose tested) as the analog aluminum hydroxide (without citric acid). There is uncertainty
in the threshold of response; the possibility that effects occur at doses <100 mg/kg/day (In the Moderate -
High hazard designation range) cannot be ruled out.
Neurotoxicity Screening
Battery (Adult)
Expected to have a moderate hazard
potential for neurotoxic effects resulting
from the presence of bioavailable metal
species.
(Estimated)
28-day, Rat, oral gavage, 0, 62.5, 250 or
1,000 mg/kg bw-day.
No treatment-related changes in behavior
or appearance, no changes in body
weight, food consumption, blood
chemistry or organ weight. No alterations
in gross or microscopic tissue
examination. RatNOAEL > 1,000 mg/kg
(highest dose tested).
90-day Rat, oral gavage, impaired
learning in a labyrinth maze test.
NOAEL: Not established
LOAEL: 35 mg Al/kg-day as aluminum
hydroxide with citric acid (only dose
tested)
(Estimated by analogy)
90-day Rat, oral gavage, impaired
learning in a labyrinth maze test.
NOAEL: Not established
Professional judgment
Estimated based on professional
judgment and analogy to aluminum
hydroxide.
Beard and Marzi, 2005; Stuer-
Lauridsen et al., 2007
Bilkei-Gorzo, 1993 (as cited in
ATSDR, 2008)
Bilkei-Gorzo, 1993
Reported in a secondary source;
study details and test conditions were
not available.
Reported in a secondary source; dose
reported as 35 mg/kg-day as
aluminum hydroxide with citric acid;
citric acid was added to increase
absorption; it is not proven that
negative effects only related to
aluminum hydroxide and not based
on citric acid; also, the background
aluminum content of the diet fed to
rats was not reported; only one dose
tested.
The background aluminum content
of the diet fed to rats was not
reported; only one dose tested
4-225
-------
Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
Other
Repeated Dose Effects
Skin Sensitization
Skin Sensitization
DATA
LOAEL: 300 mg Al/kg-day as aluminum
hydroxide (only dose tested)
(Estimated by analogy)
Oral exposure to aluminum is usually not
harmful. Some studies show that people
exposed to high levels of aluminum may
develop Alzheimer's disease, but other
studies have not found this to be true. It is
not known for certain that aluminum
causes Alzheimer's disease.
REFERENCE
ATSDR, 2008
DATA QUALITY
(aluminum hydroxide without citric
acid); study description lacks
sufficient details on individual
results.
Summary statement from a
secondary source.
MODERATE: Estimated to be of moderate hazard for immunotoxicity, due to the presence of a
bioavailable metal species, based on comparison to analogous metal salts and professional judgment.
Experimental studies indicate that oral exposure to rats produces no adverse effects at levels up to 1,000
mg/kg-day.
28-day, Rat, oral gavage, 0, 62.5, 250 or
l,000mg/kgbw-day.
No treatment-related changes in behavior
or appearance, no changes in body
weight, food consumption, blood
chemistry or organ weight. No alterations
in gross or microscopic tissue
examination.
28-day NOAEL > 1,000 mg/kg-day, rats.
Expected to have a moderate hazard
potential for immunotoxicity effects
resulting from the presence of
bioavailable metal species.
(Estimated)
Australia, 2005; Stuer-Lauridsen
et al., 2007; Submitted
confidential study
Professional judgment
Reported in a secondary source for a
commercial formulation. Test
substance was Exolit OP 930.
Estimated based on analogy to
confidential metal salts.
LOW: Negative for skin Sensitization in guinea pigs.
Non-sensitizing, guinea pigs.
Australia, 2005; Submitted
confidential study
Reported in a secondary source for a
commercial formulation. Conducted
according to OECD TG 406.
4-226
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
Respiratory Sensitization
Respiratory Sensitization
Eye Irritation
Eye Irritation
Dermal Irritation
Dermal Irritation
Endocrine Activity
Immunotoxicity
Immune System Effects
DATA
REFERENCE
DATA QUALITY
No data located.
[No data located.
LOW: Aluminum diethylphosphinate is slightly to non-irritating in rabbit eyes.
Slightly irritating, rabbits.
Not irritating, rabbits.
Australia, 2005
Submitted confidential study
Reported in a secondary source for a
commercial formulation. Conducted
according to OECD TG 405.
Study reported in a submitted
confidential study.
VERY LOW: Aluminum diethylphosphinate is not irritating to rabbit skin.
Non-irritating, rabbit.
Australia, 2005; Submitted
confidential study
Reported in a secondary source for a
commercial formulation. Conducted
according to OECD 404.
No data located.
[No data located.
Aluminum diethylphosphinate is estimated to be of moderate hazard for immunotoxicity, due to the
presence of a bioavailable metal species, based on comparison to analogous metal salts and professional
judgment.
Expected to have a moderate hazard
potential for immunotoxicity effects
resulting from the presence of
bioavailable metal species.
(Estimated)
ECOTOXICITY
ECOSAR Class
Acute Aquatic Toxicity
Fish LC50
Professional judgment
Estimated based on analogy to
confidential metal salts.
Not applicable
MODERATE: The measured green algae EC50 is between 50 and > 180 mg/L. For fish and Daphnia, LC50
values could not be determined because there were no effects at the highest concentrations tested.
Danio rerio (Zebra fish) 96-hour LC50
>1 1 mg/L
(Experimental)
Danio rerio (Zebra fish) 96-hour LC50
>9.2 mg/L
Australia, 2005
Submitted confidential study
Reported in a secondary source for a
commercial formulation.
Study reported in a submitted
confidential study.
4-227
-------
Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
Daphnid LC50
Green Algae EC so
Chronic Aquatic Toxicity
Fish ChV
DATA
(Experimental)
Danio rerio (Zebra fish) 96-hour LC50
>100mg/L
(Experimental)
Daphnia magna 48-hour LC50 >33.7
mg/L.
(Experimental)
Daphnia magna 48-hour LC50 >33 mg/L.
(Experimental)
Daphnia magna 48-hour EC50 >100
mg/L
48-hour NOEC = 100 mg/L.
(Experimental)
Scenedesmus subspicatus 72 -hour EbC50
of 60 mg/L;
Scenedesmus subspicatus 72-hour ErC50
of 76 mg/L.
(Experimental)
72-hour EC50 = 50 mg/L.
(Experimental)
Scenedesmus subspicatus 72 -hour EC50
>1 80 mg/L.
(Experimental)
REFERENCE
Submitted confidential study
Australia, 2005
Submitted confidential study
Submitted confidential study
Australia, 2005
Submitted confidential study
Submitted confidential study
DATA QUALITY
Study reported in a submitted
confidential study; Study conducted
according to EU Method C.I (Acute
Toxicity for Fish).
Reported in a secondary source for a
commercial formulation.
Study reported in a submitted
confidential study.
Study reported in a submitted
confidential study; Study conducted
according to OECD Guideline 202
(Daphnia sp. Acute Immobilization
Test).
Reported in a secondary source for a
commercial formulation.
Study reported in a submitted
confidential study.
Study details reported in a
confidential submission; Study
conducted according to EU Method
c.3 (Algal Inhibition Test).
MODERATE: An experimental value for green algae is 1.8 mg/L, while measured toxicity values for fish
and Daphnia are >10 mg/L.
ChV = 48 mg/L. (Estimated)
(Estimated)
Danio rerio (Zebra fish) 2 8 -day NOEC =
100 mg/L; LOEC >100 mg/L.
(Experimental)
Submitted confidential study
Submitted confidential study
Study reported in a submitted
confidential study.
Study reported in a submitted
confidential study; Study conducted
according to OECD Guideline 215
(Fish, Juvenile Growth Test).
4-228
-------
Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
Daphnid ChV
Green Algae ChV
DATA
Daphnia magna 21 -day EC50 =22.3
mg/L for immobility
Daphnia magna 21-day EC50 = 46.2
mg/L for reproduction
Daphnia magna 21 -day LOEC = 32
mg/L for immobility and reproduction
Daphnia magna 21 -day NOEC =10
mg/L for immobility and reproduction
(Experimental)
Green algae ChV = 1.8 mg/L.
(Experimental)
(Experimental)
REFERENCE
Australia, 2005; Submitted
confidential study
Submitted confidential study
DATA QUALITY
Reported in a secondary source for a
commercial formulation.
Study reported in a submitted
confidential study.
ENVIRONMENTAL FATE
Transport
Henry's Law Constant (atm-
m3/mole)
Sediment/Soil
Adsorption/Desorption - Koc
Level III Fugacity Model
Although the behavior of metal salts under environmental conditions is dependent on the characteristics of
the local environment (predominately pH), transport of both the metal species and the organic anion is
anticipated to be dominated by leaching through soil, runoff to aqueous environments, adsorption and/or
precipitation of the metal ion onto soil or sediment, and wet and dry deposition of dust particulates in air
to land or surface water. Volatilization of this ionic compound from either wet or dry surfaces is not
expected to be an important fate process. Nevertheless, the environmental fate of this organic salt will be
dependent on its pH-dependent dissociation, and adequate data are not available.
<10'8 (Estimated)
Approximately 0.38 according to OECD
Guideline 121 (Measured)
Professional judgment
ECHA, 20 13; Submitted
confidential study
Cutoff value for nonvolatile
compounds.
Guideline study.
This substance is not amenable to the
model.
4-229
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
Persistence
Water
Soil
Aerobic Biodegradation
Volatilization Half-life for
Model River
Volatilization Half-life for
Model Lake
Aerobic Biodegradation
Anaerobic Biodegradation
DATA
REFERENCE
DATA QUALITY
HIGH: For the organic counter-ion, estimates indicate that the half-life for ultimate aerobic
biodegradation in water is less than 60 days, which converts to moderate potential for persistence.
However, the metal ion is recalcitrant to biodegradation or other typical environmental removal processes.
Passes Ready Test: No
Test method: OECD TG 30 IF:
Manometric Respirometry Test
(Measured)
Not readily biodegradable (Measured)
Not readily biodegradable (Measured)
Organic counter-ion:
Days-weeks (primary survey model)
Weeks (ultimate survey model)
(Estimated)
Metal ion: Recalcitrant (Estimated)
Study results: Not indicated
Test method: 302C: Inherent - Modified
MITI Test (II)
Not inherently biodegradable (Measured)
Not inherently biodegradable (Measured)
>1 year
Not a significant fate process (Estimated)
>1 year
Not a significant fate process (Estimated)
No degradation according to ISO/DIS
14853
ECHA, 20 13; Submitted
confidential study
Australia, 2005
Stuer-Lauridsen et al., 2007
EPIv4.10
Professional judgment
ECHA, 20 13; Submitted
confidential study
Stuer-Lauridsen et al., 2007
Professional judgment
Professional judgment
Stuer-Lauridsen et al., 2007
Guideline study.
Reported in a secondary source for a
commercial formulation
Sufficient details were not available
to assess the quality of this study.
Metal ions will not degrade in the
environment.
Guideline study.
Sufficient details were not available
to assess the quality of this study.
Based on the magnitude of the
estimated Henry's Law constant.
Based on the magnitude of the
estimated Henry's Law constant.
No data located.
Guideline study reported in a
secondary source.
4-230
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
Air
Reactivity
Soil Biodegradation with
Product Identification
Sediment/Water
Biodegradation
Atmospheric Half-life
Photolysis
Hydrolysis
Environmental Half-life
Bioaccumulation
Fish BCF
Other BCF
BAF
Metabolism in Fish
DATA
Not a significant fate process (Estimated)
Not a significant fate process (Estimated)
Metal salts form a variety of
hydroxylation products as a function of
pH. Hydrolysis of the organic counter-ion
is not expected to be a significant fate
process (Estimated)
Organic counter-ion: <60 days
Metal ion: Recalcitrant (Estimated)
REFERENCE
Professional judgment
Mill, 2000; Professional
judgment
Professional judgment; Wolfe
and Jeffers, 2000
EPI v4.10; Professional
judgment
DATA QUALITY
No data located.
No data located.
This chemical is expected to exist
entirely in particulate form in air.
The substance does not contain
functional groups that would be
expected to absorb light at
environmentally significant
wavelengths.
The organic counter ion does not
contain functional groups that would
be expected to hydrolyze readily
under environmental conditions.
Based on estimated biodegradation
half-lives for the organic counter-ion
and metal ions will not degrade in
the environment.
LOW: Aluminum diethylphosphinate is not expected to have potential for bioaccumulation.
< 100 (Estimated)
Professional judgment
Available data suggests this chemical
will dissociate under environmental
conditions. The estimated log K0w
and limited lipophilicity are
indicative of a lower potential for
bioconcentration.
No data located.
No data located.
No data located.
4-231
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Aluminum Diethylphosphinate CASRN 225789-38-8
PROPERTY/ENDPOINT
DATA REFERENCE
ENVIRONMENTAL MONITORING AND BIOMONITORING
Environmental Monitoring
Ecological Biomonitoring
Human Biomonitoring
DATA QUALITY
No data located.
No data located.
This chemical was not included in the NHANES biomonitoring report (CDC, 201 1).
4-232
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ATSDR (2008) Toxicological profile for aluminum. Atlanta, GA: Agency for Toxic Substances and Disease Registry, U.S. Department of Health
and Human Services, http://www.atsdr.cdc.gov/toxprofiles/tp22.pdf
Australia (2005) Chemical in Exolit OP 1312. Australia. National Industrial Chemicals Notification and Assessment Scheme.
Beard A and Marzi T (2005) New phosphorus based flame retardants for E&E applications: A case study on their environmental profile in view of
European legislation o chemicals and end-of-life (REACH, WEEE, RoHS). http://www.flameretardants-
online.com/images/userdata/pdf/175_EN.pdf
Bilkei-Gorzo A (1993) Neurotoxic effect of enteral aluminum. Food Chem Toxicol 31(5):357-361.
CDC (2011) Fourth national report on human exposure to environmental chemicals, updated tables, February 2011. Centers for Disease Control
and Prevention, Department of Health and Human Services, http://www.cdc.gov/exposurereport/.
Clariant (2007) Product data sheet- flame retardants. Exolit OP 930. Clariant International Ltd.
http://www.additives.clariant.com/bu/additives/PDS_Additives.nsf/www/DS-OSTS-7SHDYA?open.
DeBoysere J and Dietz M (2005) Halogen-free flame retardants for electronic applications. http://www.onboard-
technology.com/pdf_febbraio2005/020505.pdf
ECHA (2013) Confidential submitted study. Registered substances. European Chemicals Agency, http://apps.echa.europa.eu/registered/registered-
sub.aspx.
EPA (1999) Determining the adequacy of existing data. High Production Volume (HPV) Challenge. Washington, DC: U.S. Environmental
Protection Agency, http://www.epa.gov/hpv/pubs/general/datadeqfn.pdf
EPA (2008) Flame retardants in printed circuit boards. Cincinnati, OH: U.S. Environmental Protection Agency, Design for the Environment.
EPI Estimation Programs Interface (EPI) Suite, Version 4.10. Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency.
http://www.epa.gov/opptintr/exposure/pubs/episuitedl.htm.
ESIS (2011) European chemical Substance Information System. European Commission, http://esis.jrc.ec.europa.eu/.
Mill T (2000) Photoreactions in surface waters. In: Boethling R, Mackay D, eds. Handbook of Property Estimation Methods for Chemicals,
Environmental Health Sciences. Boca Raton: Lewis Publishers.:355-381.
4-233
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Stuer-Lauridsen F, Cohr KH, Andersen TT (2007) Health and environmental assessment of alternatives to Deca-BDE in electrical and electronic
equipment. Danish Ministry of the Environment Environmental Protection Agency. http://www2.mst.dk/Udgiv/publications/2007/978-87-7052-
351-6/pdf/978-87-7052-352-3.pdf
Wolfe N and Jeffers P (2000) Hydrolysis. In: Boethling RS, Mackay D, eds. Handbook of property estimation methods for chemicals
Environmental and Health Sciences. Boca Raton, FL: Lewis Publishers.:311-333.
4-234
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Aluminum Hydroxide
VL = Very Low hazard L = Low hazard = Moderate hazard H = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion
by-products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the
table.
§ Based on analogy to experimental data for a structurally similar compound. R Recalcitrant: Substance is comprised of metallic species (or metalloids) that will not degrade, but may
change oxidation state or undergo complexation processes under environmental conditions. ¥ Aquatic toxicity: EPA/DfE criteria are based in large part upon water column exposures
which may not be adequate for poorly soluble substances such as many flame retardants that may partition to sediment and particulates.
Chemical
CASRN
Human Health Effects
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Aluminum Hydroxide
21645-51-2
V
V
VL VL
4-235
-------
Aluminum hydroxide
HO
Xl-OH
HO
SMILES: O[A1](O)O
CASRN: 21645-5 1-2
MW: 78.01
MF: A1H3O3
Physical Forms:
Neat: Solid
Use: Flame retardant
Synonyms: Aluminum hydroxide (A1(OH)3), Gibbsite, Bayersite, Nordstrandite, Aluminum trihydrate
Chemical Considerations: This alternative is an inorganic compound and in the absence of experimental data, professional judgment using chemical class and
structural considerations were used to complete this hazard profile.
Polymeric: No
Oligomeric: Not applicable
Metabolites, Degradates and Transformation Products: None
Analog: Unspecified analogous aluminum compounds were discussed in the Analog Structure: Not app
structural based professional judgment rationale
Endpoint(s) using analog values: Carcinogenicity, reproductive effects,
immunotoxicity
Structural Alerts: Aluminum compounds (EPA, 2010).
Risk Phrases: Not classified by Annex I Directive 67/548/European Economic Community & IUCLID (Pakalin
icable
et al., 2007).
Hazard and Risk Assessments: Risk assessment completed for aluminum hydroxide by the National Research Council Subcommittee on Flame-Retardant Chemicals
(NRC, 2000). Hazard assessment completed for Design for the Environment Alternatives Assessment for Flame Retardants in Printed Circuit Boards, Review Draft,
November 8, 2008. (EPA, 2008; NRC, 2000).
4-236
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
Water Solubility (mg/L)
Decomposes at approximately 200
(Measured)
Decomposes at approximately 150-220 to
A12O3 and H2O (Measured)
Decomposes (loses water) at 300 (Measured)
The substance is expected to decompose
before boiling. (Estimated)
<10'8 (Estimated)
< 0.09 at 20°C, pH 6-7
Organisation for Economic Cooperation and
Development (OECD) Guideline 105 Purity
calculated based on aluminum oxide
(Measured)
0.01 17 to 0.0947 at pH 7.5-8.1 and 21-24°C
Reported as 1 1.7 to 94.7 (ig/L A1(OH)3 and
4.06 to 32.75 jig/LAl
100 mg of A1(OH)3 was dissolved in 100 mL
distilled water or test media prepared
according to OECD 201, 202 or 21 1, filtered,
and then analyzed using Graphite Furnace
Atomic Absorption Spectrometry (GF AAS)
and Inductively coupled plasma atomic
emission spectroscopy (ICP-AES) (Measured)
1.5 at 20°C at pH 7 (Measured)
1.5xlO"2 at 20°C at pH 8-9 (Measured)
European Commission, 2000
European Commission, 2000
Lewis, 2000
Professional judgment
EPA, 1999; Professional
judgment
ECHA, 2013
Submitted confidential study
European Commission, 2000
European Commission, 2000
Adequate.
Adequate.
Adequate.
Based on the values included in the
melting point section of this assessment.
Cutoff value for compounds that are
anticipated to be nonvolatile accorded to
HPV assessment guidance
Guideline study reporting non-specific
value that is in agreement with other
experimental values indicating poor
solubility.
Reported in a nonguideline study done to
prepare for toxicity testing.
Measured values were not consistently
reported, but are sufficient for subsequent
components of the hazard assessment.
Measured values were not consistently
reported, but are sufficient for subsequent
components of the hazard assessment.
4-237
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
Log Kow
Flammability (Flash Point)
Explosivity
Pyrolysis
pH
pKa
Particle Size
DATA
Insoluble in water (Estimated)
Practically insoluble in water (Estimated)
Not flammable (Measured)
Not explosive (Estimated)
Not flammable (Estimated)
pH of a saturated solution in water was 6 to 7
(Measured)
Not applicable (Estimated)
<100 (im; 88% for the fine unground hydrate
and 52-61% for the coarse unground hydrate
< 2 (im; 1.3-2% for the fine unground hydrate
and 1% for the coarse unground hydrate
According to OECD Guideline 110 (Particle
Size Distribution / Fibre Length and Diameter
Distributions)
(Measured)
REFERENCE
Lide, 2006
Lewis, 2000; O'Neil et al.,
2001
ECHA, 2013
European Commission, 2000
European Commission, 2000
ECHA, 2013
Professional judgment
ECHA, 2013
DATA QUALITY
Measured values were not consistently
reported, but are sufficient for subsequent
components of the hazard assessment.
Measured values were not consistently
reported, but are sufficient for subsequent
components of the hazard assessment.
No data located. This inorganic compound
is not amenable to available estimation
methods.
Reported in a secondary source and based
on its use as a flame retardant.
Adequate.
Adequate.
Determined in a water solubility study.
Determination of dissociation constant is
not possible due to the insolubility of the
test substance.
Guideline study reported in a secondary
source.
4-238
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
HUMAN HEALTH EFFECTS
Toxicokinetics
Dermal Absorption in vitro
Absorption,
Distribution,
Metabolism
& Excretion
Oral, Dermal or Inhaled
Toxicokinetic data suggest that aluminum hydroxide is not readily absorbed in humans following oral exposure.
Excretion occurs primarily through feces, and less so in urine. Animal studies indicated that aluminum
accumulated in intestinal cells but was not found in other tissues.
26 Al labeled aluminum hydroxide (in water
suspension) was administered to rats by oral
gavage. The mean fractional uptake
(absorption) into the bloodstream of 26A1 from
aluminum hydroxide was 0.025±0.041%.
Compared to the uptake into the bloodstream
of rats injected with 0. 19 ng 26A1 labeled
aluminum citrate in solution, aluminum
hydroxide as an insoluble compound is less
bioavailable than soluble compounds (mean
fractional uptake of 26 Aluminum citrate: 0.079
±0.0057%; 26Aluminum hydroxide:
0.025±0.041%).
After rats were exposed to aluminum
hydroxide in drinking water for 10 weeks,
aluminum accumulated in intestinal cells but
not in other tissues.
In metabolic studies in humans, 12% of an
oral load of aluminum hydroxide was
retained, but absorption was not calculated.
The absorbed fraction of aluminum hydroxide
in two human males dosed orally was 0.01%.
Adult humans with renal failure who ingested
1.5-3.0 g aluminum hydroxide per day for 20-
32 days absorbed between 100 and 568 mg
aluminum per day (7-19% of the dose).
Adult humans taking aluminum antacids had
a 3 -fold increase of aluminum levels in the
ECHA, 2013
HSDB, 2013
HSDB, 2013
HSDB, 2013
HSDB, 2013
ATSDR, 2008
No data located.
Reported in a secondary source. Adequate,
performed in accordance with OECD
guidelines and Good Laboratory Practices
(GLP); Aluminum hydroxide, was
suspended in water with added 1%
carboxymethylcellulose (to maintain a
suspension).
Reported in a secondary source, study
details and test conditions were not
provided.
Reported in a secondary source, study
details and test conditions were not
provided.
Reported in a secondary source, study
details and test conditions were not
provided.
Reported in a secondary source, study
details and test conditions were not
provided.
Reported in a secondary source, study
details were not provided.
4-239
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
Other
Acute Mammalian Toxicity
Acute
Lethality
Oral
Dermal
Inhalation
Carcinogenicity
Genotoxicity
OncoLogic Results
Carcinogenicity (Rat and
Mouse)
Combined Chronic
Toxicity/Carcinogenicity
Other
Gene Mutation in vitro
Gene Mutation in vivo
Chromosomal Aberrations in
vitro
DATA
urine; minimal aluminum was absorbed and
was mostly excreted in the feces.
Certain complexing agents such as citric acid
and lactic acid can increase the
bioavailability /absorption of aluminum
hydroxide.
REFERENCE
Gomez etal., 1991;Bilkei-
Gorzo, 1993; Colamina et al.,
1994; Professional judgment.
DATA QUALITY
Based on studies using citric acid and
lactic acid in conjunction with aluminum
hydroxide and professional judgment.
LOW: Aluminum hydroxide has low acute toxicity based on oral LD50 > 2,000 mg/kg in rats.
Rat oral LD50 >5,000 mg/kg
Rat oral LD50 >2,000 mg/kg
European Commission, 2000
ECHA, 2013
Reported in a secondary source, study
details and test conditions were not
provided.
Reported in a secondary source.
Performed in accordance with OECD
guidelines and GLP.
No data located.
No data located.
LOW: Aluminum hydroxide is estimated to be of low hazard for Carcinogenicity based on professional judgment
and comparison to analogous aluminum compounds.
Low potential for Carcinogenicity
(Estimated)
Professional judgment
No data located.
Estimated based on professional judgment
and comparison to analogous aluminum
compounds.
No data located.
No data located.
LOW: Aluminum hydroxide did not cause mutations in mammalian cells in vitro and did not result in an
increased incidence of micronuclei in rats in vivo.
Negative in mouse lymphoma cells with and
without metabolic activation
ECHA, 2013
Adequate, performed in accordance with
OECD guidelines and GLP.
No data located.
No data located.
4-240
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
Chromosomal Aberrations in
vivo
DNA Damage and Repair
Other
Reproductive Effects
Reproduction/Developmental
Toxicity Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Reproduction and Fertility
Effects
Other
Developmental Effects
Reproduction/
Developmental Toxicity
Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
DATA
Negative for induction of micronuclei in
polychromatic erythrocytes of bone marrow
in Sprague-Dawley rats
REFERENCE
ECHA, 2013
DATA QUALITY
Adequate, performed in accordance with
OECD guidelines and GLP.
No data located.
No data located.
LOW: Aluminum hydroxide is estimated to be of low hazard for reproductive effects based on professional
judgment and comparison to analogous aluminum compounds.
Low potential for reproductive effects
(Estimated)
Professional judgment
No data located.
No data located.
Estimated based on professional judgment
and comparison to analogous aluminum
compounds.
No data located.
LOW: Aluminum hydroxide does not show developmental toxicity when administered orally to rats or mice at
dose levels up to 266 mg/kg-day. There were no data located regarding developmental neurotoxicity.
No data located.
No data located.
4-241
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Prenatal Development
Rat (Sprague-Dawley), oral (gavage), 384
mg/kg/day A1(OH)3 alone or 384 mg/kg/day
A1(OH)3 concurrent with 62 mg/kg/day citric
acid on GD 6-15.
No significant differences between controls
and Al-treated rats on pre- or
postimplantation loss, number of live fetuses
per litter, or sex ratio. Reduced fetal body
weight and increased incidence of skeletal
variations in groups receiving A1(OH)3 and
citric acid.
Gomez etal., 1991
Study details reported in a primary source.
Citric acid was added to increase
absorption; it is not proven that effects are
solely related to aluminum hydroxide and
not based on citric acid.
Swiss mice, oral (gavage), 166 mg/kg
A1(OH)3 alone or 166 mg/kg A1(OH)3
concurrent with 570 mg/kg lactic acid on GD
6-15.
Maternal toxicity was evident in groups
treated with A1(OH)3 and lactic acid. There
were no embryotoxic effects in any group.
There was a non-statistically significant
increased incidence of skeletal variations in
groups receiving A1(OH)3 and lactic acid.
Colominaetal., 1992
Study details reported in a primary source
Lactic acid was added to increase
absorption; it is not proven that effects are
solely related to aluminum hydroxide and
not based on lactic acid.
Rat (Sprague-Dawley), oral (gavage), 0 or
384 mg/kg-day on GD 6-15
There were no significant changes in pre- or
post-implantation losses, number of live
fetuses per litter, sex ratio, fetal body weight,
incidence of malformations, or skeletal
variations.
NOAEL: 384 mg/kg-day (only dose tested)
LOAEL: Not established
Gomez etal., 1991
Study details reported in a primary source;
only one dose tested.
Mouse, oral, no developmental effects.
NOAEL: 266 mg/kg-day (highest dose tested)
Domingo et al., 1989
Adequate.
Mouse, oral, no developmental effects.
NOAEL: 268 mg/kg-day (highest dose tested)
4-242
Gomez etal., 1989
Abstract only.
-------
Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
Postnatal Development
Prenatal and Postnatal
Development
Developmental Neurotoxicity
Other
DATA
Mouse, oral, no developmental effects.
NOAEL: 300 mg/kg-day (only dose tested)
Rat, oral (gavage), 192, 384, 768 mg/kg-day
on GD 6-15
There were no significant changes in the
number of litters, corpora lutea, total
implants, pre- or post-implantation losses, and
live fetuses per litter. There were also no
significant differences in the sex ratio, fetal
body weight, or fetal malformations.
NOAEL: 768 mg/kg-day (highest dose tested)
LOAEL: Not established
Rat, oral, no developmental effects.
NOAEL: 384 mg/kg-day (only dose tested)
Low potential for developmental
neurotoxicity
(Estimated)
REFERENCE
Colamina et al., 1994
Gomez etal., 1990
Llobetetal., 1990
Professional judgment
DATA QUALITY
Abstract only.
Study details reported in a primary source.
Abstract only.
No data located.
No data located.
Estimated based on analogy to structurally
similar compounds.
No data located.
4-243
-------
Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Neurotoxicity
MODERATE: Aluminum hydroxide is expected to be of moderate hazard for neurotoxicity. Impaired learning
in a labyrinth maze test was reported in a 90-day oral study in rats at 300 mg Al/kg/day as aluminum hydroxide
(only dose tested; a NOAEL was not identified). Impaired learning in a labyrinth maze test was also reported in
rats orally exposed to 100 mg Al/kg/day as aluminum hydroxide in combination with 30 mg/kg-day citric acid
(only dose tested; a NOAEL was not identified). There is uncertainty in the threshold of response for this effect
for exposure to aluminum hydroxide alone and in combination with citric acid. The possibility that effects occur
at doses <100 mg/kg/day (in the Moderate - High hazard designation range) cannot be ruled out; therefore a
Moderate hazard designation was assigned.
Neurotoxicity Screening
Battery (Adult)
30-day Rat, oral diet, no significant effects
noted.
NOAEL: 1,252 mg Al/kg-day (highest dose
tested)
90-day Rat, oral gavage, impaired learning in
a labyrinth maze test
NOAEL: not established
LOAEL: 300 mg/kg-bw (only dose tested)
Low potential for repeated dose effects but
moderate potential for immunotoxicity.
(Estimated)
Thorne et al., 1986; Thorne
etal., 1987; ATSDR, 2008
Bilkei-Gorzo, 1993
Professional judgment
Reported in a secondary source.
The background aluminum content of the
diet fed to rats was not reported; only one
dose tested; study description lacks
sufficient details on individual results.
Exposure to 100 mg /kg-day as aluminum
hydroxide combined with 30 mg/kg-day
citric acid (only dose tested) was also
investigated for which impaired learning
was observed; citric acid was added to
increase absorption; it is not proven that
negative effects only related to aluminum
hydroxide and not based on citric acid.
Estimated based on professional judgment
and comparison to analogous aluminum
compounds.
Other
Oral exposure to aluminum is usually not
harmful. Some studies show that people
exposed to high levels of aluminum may
develop Alzheimer's disease, but other
studies have not found this to be true. It is not
known for certain that aluminum causes
Alzheimer's disease.
ATSDR, 2008
Summary statement from a secondary
source.
4-244
-------
Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
Repeated Dose Effects
Immune System Effects
Skin Sensitization
Skin Sensitization
Respiratory Sensitization
Respiratory Sensitization
Eye Irritation
Eye Irritation
DATA
REFERENCE
DATA QUALITY
MODERATE: Aluminum hydroxide is estimated to have potential for immunotoxicity based on professional
judgment and comparison to analogous aluminum compounds. Aluminum hydroxide is of low hazard for other
repeated dose effects based on an experimental study indicating no adverse effects in rats following oral doses up
to 14,470 ppm (302 mg/kg-day). In addition, a low potential for repeated dose effect is estimated based on
professional judgment and comparison to analogous aluminum compounds.
Low potential for repeated dose effects but
moderate potential for immunotoxicity
(Estimated)
2 8 -day Rat (male), oral diet, no systemic
effects noted. NOAEL: 14,470 ppm/diet (302
mg aluminum/kg-day; highest dose tested).
6-Week human, oral.
LOAEL: 25 mg Al/kg-day (Reduction in
primed cytotoxic T-cells, only dose tested).
Moderate potential for immunotoxicity.
(Estimated)
Professional judgment
Hicks etal., 1987
ATSDR, 2008
Professional judgment
Estimated based on professional judgment
and comparison to analogous aluminum
compounds.
Study details from primary source.
Study details reported in a secondary
source.
Estimated based on professional judgment
and comparison to analogous aluminum
compounds.
LOW: Aluminum hydroxide is not a skin sensitizer.
Low potential for skin Sensitization.
(Estimated)
Not sensitizing to guinea pigs in an in vivo
maximization test
Professional judgment
ECHA, 2013
Estimated based on professional judgment
and comparison to analogous aluminum
compounds.
Reported in a secondary source;
conducted in accordance with OECD
guidelines and GLP.
No data located.
No data located.
VERY LOW: Aluminum hydroxide is not irritating to rabbit eyes.
Not irritating, rabbits.
ECHA, 2013
Reported in a secondary source;
Conducted in accordance with OECD
guidelines and GLP.
4-245
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
Dermal Irritation
Dermal Irritation
Endocrine Activity
Immunotoxicity
Immune System Effects
DATA
REFERENCE
DATA QUALITY
VERY LOW: Aluminum hydroxide is not irritating to skin.
Not irritating, rabbits.
Not irritating, rabbits, mice and pigs
ECHA, 2013
ECHA, 2013
Reported in a secondary source.
Conducted in accordance with OECD
guidelines and GLP.
Reported in a secondary source;
nonguideline studies.
No data located.
No data located.
Aluminum hydroxide is estimated to have potential for immunotoxicity based on professional judgment and
comparison to analogous aluminum compounds.
Moderate potential for immunotoxicity.
(Estimated)
6-Week human, oral.
LOAEL: 25 mg Al/kg-day (Reduction in
primed cytotoxic T-cells, only dose tested).
Professional judgment
ATSDR, 2008
Estimated based on professional judgment
and comparison to analogous aluminum
compounds.
Reported in a secondary source.
ECOTOXICITY
ECOSAR Class
Acute Aquatic Toxicity
Fish LC50
Daphnid LC50
Not applicable
LOW: Effect values from experimental studies for fish, daphnia and algae indicate no effects at the saturation
limit (NES).
Salmo trutta 96-hour NOEC >100 mg/L
(Experimental)
Daphnia magna 48-hour EC50 = NES
static test conditions.
(Experimental)
Daphnia magna 48 -hour NOEC >100 mg/L
(Experimental)
Daphnia magna 48 -hour NOEC > 0.135
European Commission, 2000
Tothova and Simo, 2013a
European Commission, 2000
ECHA, 2013
Reported in a secondary source. The effect
concentration is greater than the measured
water solubility.
Study details reported in an unpublished
study; conducted according to OECD 202;
no effects at test substance saturation limit
(> 0.079 mg/L).
Reported in a secondary source. Study
details and test conditions were not
available and the effect concentration is
greater than the measured water solubility.
Study conducted with aluminum powder.
4-246
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
Green Algae EC50
Chronic Aquatic Toxicity
Fish ChV
Daphnid ChV
Green Algae ChV
DATA
mg/L
(Experimental)
Daphnia magna 48 -hr EC50 = 0.8240 mg/L
(Experimental)
Desmodesmus subspicatus 72-hour EC50 =
NES
(Experimental)
Selenastrum capricornutum 96-hour EC50 =
0.6560 mg/L
(Experimental)
Pseudokirchneriella subcapitata 96-hour
EC50 = 0.46 mg/L
(Experimental)
REFERENCE
TSCATS, 1996
Tothova and Simo, 2013c
TSCATS, 1996
ECHA, 2013
DATA QUALITY
Study incorrectly cited in source; results
are for a different test substance,
vanadium hydroxide oxide.
Study details reported in an unpublished
study; conducted according to OECD 201;
no effects at test substance saturation limit
(> 0.078 mg/L).
Study incorrectly cited in source; results
are for a different test substance,
vanadium hydroxide oxide.
Reported in a secondary source. EC50
range: 0.57 mg/L at pH of 7.6 and 0.46
mg/L at pH of 8.2. The water solubility of
aluminum hydroxide under basic pH
conditions is not available; experimental
details are not sufficient to address the
confidence limits of these data points.
LOW: Experimental data for daphnia and algae indicate NES. Although there were no experimental data for
fish located, the available chronic toxicity data for daphnia and algae suggests low chronic toxicity for fish.
Pimephales promelas 42-day NOEC = 0.102
mg/L, LOEC = 0.209 mg/L
(Experimental)
Daphnia magna 21 -day ChV = NES
semi-static test conditions
(Experimental)
Daphnia magna 21 -day NOEC = 0.091 mg/L,
LOEC = 0.1 97 mg/L
(Experimental)
Selenastrum capricornutum 72-hour NOEC
> 100 mg/L
(Experimental)
TSCATS, 1996
Tothova and Simo, 2013b
TSCATS, 1996
European Commission, 2000
Study incorrectly cited in source; results
are for a different test substance,
vanadium hydroxide oxide.
Study details reported in an unpublished
study; conducted according to OECD 211;
no effects at test substance saturation limit
(> 0.076 mg/L).
Study incorrectly cited in source; results
are for a different test substance,
vanadium hydroxide oxide.
Reported in a secondary source. The effect
concentration is greater than the measured
water solubility.
4-247
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
ENVIRONMENTAL FATE
Transport
Henry's Law Constant (atm-
m3/mole)
Sediment/Soil
Adsorption/Desorption - Koc
Level III Fugacity Model
Persistence
Water
Soil
Aerobic Biodegradation
Volatilization Half-life for
Model River
Volatilization Half-life for
Model Lake
Aerobic Biodegradation
Anaerobic Biodegradation
Soil Biodegradation with
Product Identification
Sediment/Water
Biodegradation
Although the behavior of aluminum salts under environmental conditions is dependent on the characteristics of
the local environment (predominately pH), transport of the aluminum (III) species is anticipated to be dominated
by leaching through soil; runoff to aqueous environments; adsorption and/or precipitation of the metal ion onto
soil or sediment; and wet and dry deposition dust particulates in air to land or surface water. Volatilization of
this ionic compound from either wet or dry surfaces is not expected to be an important fate process. Under acidic
pHs typically encountered in the environment, it may form insoluble polymeric aluminum hydroxide colloids
while under basic conditions; anionic aluminum hydroxide is expected to predominate. Other factors influencing
its behavior include the presence of dissolved organic matter, the extent of absorption on suspended particles,
and the presence of other aluminum species.
<10'8 (Estimated)
>30,000 (Estimated)
Professional judgment
EPA, 2004; Professional
judgment
Cutoff value for nonvolatile compounds.
Cutoff value fornonmobile compounds.
No data located.
HIGH: As an inorganic material, aluminum hydroxide is not expected to biodegrade or oxidize under typical
environmental conditions. Aluminum hydroxide does not absorb light at environmentally relevant wavelengths
and is not expected to photolyze. No degradation processes for aluminum hydroxide under typical environmental
conditions were identified.
Recalcitrant (Estimated)
>1 year (Estimated)
>1 year (Estimated)
Recalcitrant (Estimated)
Recalcitrant
Professional judgment
Professional judgment
Professional judgment
Professional judgment
Professional judgment
Substance is or contains inorganic
elements, such as metal ions or oxides,
that are expected to be found in the
environment >180 days after release.
Based on the magnitude of the estimated
Henry's Law constant.
Based on the magnitude of the estimated
Henry's Law constant.
Substance contains inorganic elements.
Substance contains inorganic elements.
No data located.
No data located.
4-248
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Aluminum Hydroxide CASRN 21645-51-2
PROPERTY/ENDPOINT
Air
Reactivity
Atmospheric Half-life
Photolysis
Hydrolysis
Environmental Half-life
Bioaccumulation
Fish BCF
Other BCF
BAF
Metabolism in Fish
DATA
>1 year (Estimated)
Not a significant fate process (Estimated)
REFERENCE
Professional judgment
Professional judgment
DATA QUALITY
Substance contains inorganic elements.
Aluminum hydroxide does not absorb UV
light at environmentally relevant
wavelengths and is not expected to
undergo photolysis.
Dissociation of aluminum hydroxide in
environmental waters is dependent both
on the pH and the local concentration of
other aluminum species; dissociation will
not occur unless in highly acidic waters,
e.g.,pH3.
No data located. Inorganic compounds are
outside the estimation domain (EPI).
LOW: Aluminum hydroxide is not expected to bioaccumulate.
<100 (Estimated)
<100 (Estimated)
Professional judgment
Professional judgment
Aluminum hydroxide is an inorganic
compound and is not anticipated to
bioaccumulate orbioconcentrate. This
inorganic compound is not amenable to
available quantitative structure activity
relationship (QSAR) models.
No data located.
Aluminum hydroxide is an inorganic
compound and is not anticipated to
bioaccumulate orbioconcentrate. This
inorganic compound is not amenable to
available QSAR models.
No data located.
ENVIRONMENTAL MONITORING AND BIOMONITORING
Environmental Monitoring
Ecological Biomonitoring
Human Biomonitoring
No data located.
No data located.
This chemical was not included in the NHANES biomonitoring report. (CDC, 201 1).
4-249
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ATSDR (2008) Toxicological profile for aluminum. Atlanta, GA: Agency for Toxic Substances and Disease Registry, U.S. Department of Health
and Human Services, http://www.atsdr.cdc.gov/toxprofiles/tp22.pdf
Bilkei-Gorzo A (1993) Neurotoxic effect of enteral aluminum. Food Chem Toxicol 31(5):357-361.
CDC (2011) Fourth national report on human exposure to environmental chemicals, updated tables, February 2011. Centers for Disease Control
and Prevention, Department of Health and Human Services, http://www.cdc.gov/exposurereport/.
Colomina MT, Gomez M, Domingo JL, et al. (1992) Concurrent ingestion of lactate and aluminum can result in developmental toxicity in mice.
77(1):95-106.
Colomina MT, Gomez M, Domingo JL, et al. (1994) Lack of maternal and developmental toxicity in mice given high doses of aluminum
hydroxide and ascorbic acid during gestation. Pharmacol Toxicol 74:236-239.
Domingo JL, Gomez M, Bosque MA, et al. (1989) Lack of teratogenicity of aluminum hydroxide in mice. Life Sci 45:243-247.
EC (2000) Aluminum hydroxide. IUCLID dataset. European Commission. European Chemicals Bureau.
ECHA (2013) Aluminum hydroxide. Registered substances. European Chemicals Agency.
http://apps.echa.europa.eu/registered/data/dossiers/DISS-9e9ede9a-Ofd5-2b35-e044-00144f67d031/DISS-9e9ede9a-Ofd5-2b35-e044-
00144f67d031_DISS-9e9ede9a-Ofd5-2b35-e044-00144f67d031.html.
EPA (1999) Determining the adequacy of existing data. High Production Volume (HPV) Challenge. Washington, DC: U.S. Environmental
Protection Agency, http://www.epa.gov/hpv/pubs/general/datadeqm.pdf
EPA (2004) Pollution prevention (P2) framework. Washington, DC: U.S. Environmental Protection Agency, Office of Pollution Prevention and
Toxics, http://www.epa.gov/oppt/sf/pubs/p2frame-june05a2.pdf
EPA (2008) Flame retardants in printed circuit boards. Cincinnati, OH: U.S. Environmental Protection Agency, Design for the Environment.
EPA (2010) TSCA new chemicals program (NCP) chemical categories. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/newchems/pubs/npcchemicalcategories.pdf
Gomez M, Bosque MA, Domingo JL, et al. (1990) Evaluation of the maternal and developmental toxicity of aluminum from high doses of
aluminum hydroxide in rats. Vet Hum Toxicol 32(6):545-548.
4-250
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Gomez M, Domingo J, Llobet J (1991) Developmental toxicity evaluation of oral aluminum in rats: Influence of citrate. 13:323-328.
Gomez M, Domingo JL, Bosque A, et al. (1989) Teratology study of aluminum hydroxide in mice. Toxicologist 9(1):273.
HSDB (2013) Aluminum hydroxide. Hazardous Substances Data Bank. National Library of Medicine, http://toxnet.nlm.nih.gov/cgi-
bin/sis/htmlgen?HSDB.
Hicks JS, Hackett DS, Sprague GL (1987) Toxicity of aluminum concentration in bone following dietary administration of two sodium aluminum
phosphate formulations in rats. Food Chem Toxicol 25(7):533-538.
Lewis R (2000) Sax's dangerous properties of industrial materials. 10th ed. New York, NY: John Wiley & Sons, Inc.
Lide DR (2006) Handbook of chemistry and physics. Boca Raton, FL: CRC Press.
Llobet JM, Gomez M, Domingo JL, et al. (1990) Teratology studies of oral aluminum hydroxide, aluminum citrate, and aluminum hydroxide
together with citric acid in rats. Teratology 42(227A)
NRC (2000) Subcommittee on flame-retardant chemicals. Toxicological risks of selected flame retardant chemicals. Washington, DC: National
Research Council. National Academy Press.
O'Neil MJ, Budavari S, Smith A, et al. (2001) Merck Index. Whitehouse Station, NJ: Merck & Co.
Pakalin S, Cole T, Steinkeliner J, et al. (2007) Review on production processes of decabromodiphenyl ether (DECABDE) used in polymeric
applications in electrical and electronic equipment, and assessment of the availability of potential alternatives to DECABDE. European Chemicals
Bureau, European Commission, http://publications.jrc.ec.europa.eu/repository/bitstream/l 1111111 l/5259/l/EUR%2022693.pdf
TSCATS (1996) Toxic Substance Control Act Test Submission Database.
Thorne BM, Cook A, Donohoe T, et al. (1987) Aluminum toxicity and behavior in the weanling Long-Evans rat. 25(2): 129-132.
Thorne BM, Donohoe T, Lin K, et al. (1986) Aluminum ingestion and behavior in the Long-Evans rat. Physiol Behav 36:63-67.
Tothova E and Simo K (2013a) Final report of the study no. 13 - 018113: Ecotoxicological testing of product APYRAL 40CD by test OECD 202
Daphnia sp., acute immobilisation test [unpublished]. Slovakia: Sponsor-Nabaltec AG; Test Facility-Ekologicke Laboratoria.
Tothova E and Simo K (2013b) Final report of the study no. 13 - 018115: Ecotoxicological testing of product APYRAL 40CD by test OECD 211
Daphnia magna reproduction test [unpublished]. Slovakia: Sponsor-Nabaltec AG; Test Facility-Ekologicke Laboratoria.
4-251
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Tothova E and Simo K (2013c) Final report of the study no. 13 - 018114: Ecotoxicological testing of product APYRAL 40CD by test OECD 201
Alga, Growth Inhibition Test [unpublished]. Slovakia: Sponsor-Nabaltec AG; Test Facility-Ekologicke Laboratoria.
4-252
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Magnesium Hydroxide
VL = Very Low hazard L = Low hazard = Moderate hazard H = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion
by-products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the
table.
R Recalcitrant: Substance is comprised of metallic species (or metalloids) that will not degrade, but may change oxidation state or undergo complexation processes under
environmental conditions. ¥ Aquatic toxicity: EPA/DfE criteria are based in large part upon water column exposures which may not be adequate for poorly soluble substances such
as many flame retardants that may partition to sediment and particulates.
Chemical
CASRN
Human Health Effects
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Magnesium Hydroxide
1309-42-8
4-253
-------
Magnesium Hydroxide
OH
H0.Mg
CASRN: 1309-42-8
MW: 58.32
MF: MgH2O2
Physical Forms:
Neat: Solid
Use: Flame retardant
SMILES: O[Mg]O
Synonyms: Magnesium hydroxide (Mg(OH)2); Brucite, Milk of Magnesia; AlcanexNHC 25, Asahi Glass 200-06, Baschem 12, Combustrol 500, Duhor, DuhorN,
Ebson RF, FloMag H, FloMag HUS, Hydro-mag MA, Hydrofy G 1.5, Hydrofy G 2.5, Hydrofy N, Kisuma 4AF, Kisuma 5, Kisuma 5A, Kisuma 5B, Kisuma 5B-N,
Kisuma 5BG, Kisuma 5E, Kisuma 78, Kisuma S 4, Kyowamag F, Lycal 96 HSE, Mag Chem MH 10, Magnesia hydrate, MagneClear 58, Magnesia magma,
Magnesiamaito, Magnesium dihydroxide, Magnesium hydroxide gel, Magnesium(II) hydroxide, Magnifin H 10, Magox, Marinco H, Marinco H 1241, Martinal VPF
8812, Milmag, Mint-O-Mag, Nemalite, Oxaine M, Phillips Magnesia Tablets, Phillips Milk of Magnesia Liquid, Reachim, Star 200, Versamag
Chemical Considerations: This alternative is an inorganic compound. In the absence of experimental data, professional judgment using chemical class and structural
considerations were used to complete this hazard profile.
Polymeric: No
Oligomeric: Not applicable
Metabolites, Degradates and Transformation Products: Not applicable
Analog: No analogs; Mg + ions are expected to form when Mg(OH)2 and other
magnesium containing compounds dissociate in aqueous conditions. Studies
included in this assessment include other sources of Mg2+ like MgCl2.
Endpoint(s) using analog values: Not applicable
Analog Structure: Not applicable
Structural Alerts: None
Risk Phrases: Not classified by Annex VI Regulation (EC) No 1272/2008 (ESIS, 2011).
Hazard and Risk Assessments: Risk assessment completed for magnesium hydroxide by the National Academy of Sciences in 2000 (NAS, 2000).
4-254
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
Water Solubility (mg/L)
Decomposes at 350 (Measured)
Decomposes at 380 (Measured)
350 (Measured)
Will decompose before boiling
(Measured)
<10"8 (Estimated)
1.78 at 20°C, pH 8.3 According to
Organisation for Economic Cooperation
and Development (OECD 105) Column
elution method. (Measured)
9 at 18°C (Measured)
1 at 20°C (Measured)
6 at 20°C (Measured)
<8 at 20°C (Measured)
Hodgman, 1959; Lewis, 1997;
Lewis, 2000
IUCLID, 2000
Lide, 2000; Aldrich Chemical
Company, 2006
IUCLID, 2000
EPA, 1999; Professional
judgment
ECHA, 2013
Hodgman, 1959; IUCLID, 2000
IUCLID, 2000
IUCLID, 2000
IUCLID, 2000
MgO and H2O are decomposition
products.
MgO and H2O are decomposition
products.
MgO and H2O are decomposition
products.
Decomposition occurs upon melting
as described in additional sources
above.
Cutoff value for nonvolatile
compounds according to HPV
assessment guidance. This inorganic
compound is not amenable to
available estimation methods.
Guideline study; results are in
agreement with other experimental
values.
Measured values, which span a
relatively narrow range, are
consistently reported in numerous
sources.
Measured values, which span a
relatively narrow range, are
consistently reported in numerous
sources.
Measured values, which span a
relatively narrow range, are
consistently reported in numerous
sources.
Measured values, which span a
relatively narrow range, are
consistently reported in numerous
4-255
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Log Kow
Flammability (Flash Point)
Explosivity
Pyrolysis
pH
pKa
Particle Size
DATA
40 at 100°C (Measured)
Not flammable (Measured)
Not explosive (Estimated)
Not applicable (Estimated)
pH of a saturated solution in water was
8.3 (Measured)
9.5-10.5 (Measured)
DIG = mean 2. 013 (im
D50 = mean 13.915 (im
D90 = mean 154.107 (im
According to OECD Guideline 1 10
(Particle Size Distribution / Fibre Length
and Diameter Distributions). (Estimated)
REFERENCE
Hodgman, 1959
IUCLID, 2000
IUCLID, 2000
Professional judgment
ECHA, 2013
O'Neiletal., 2011
ECHA, 2013
DATA QUALITY
sources.
Value obtained at an elevated
temperature.
No data located; inorganic
compounds are outside the
estimation domain of EPI.
Reported in a secondary source and
based on its use as a flame retardant.
Adequate.
Inorganic compounds do not
undergo pyrolysis.
Reported in a secondary source,
determined from a water solubility
study.
Reported in a secondary source,
limited study details provided.
No data located.
Guideline study reported in a
secondary source.
4-256
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
HUMAN HEALTH EFFECTS
Toxicokinetics
Dermal Absorption in vitro
Absorption,
Distribution,
Metabolism &
Excretion
Oral, Dermal or Inhaled
Other
Acute Mammalian Toxicity
Acute Lethality
Oral
Dermal
Inhalation
Carcinogenicity
OncoLogic Results
Carcinogenicity (Rat and
Mouse)
Some magnesium hydroxide is absorbed following ingestion and is excreted primarily in urine.
The magnesium ion is poorly absorbed;
when taken orally, only 5-15% of the
magnesium from a dose of magnesium
hydroxide is absorbed and this
magnesium is readily excreted in the
urine, if kidney function is normal.
IUCLID, 2000
Reported in a secondary source,
limited study details provided.
No data located.
LOW: Acute lethality values suggest that magnesium hydroxide is of low concern for acute toxicity for
oral exposure. There were no data located regarding acute dermal exposure.
Rat oral LD50 = 8,500 mg/kg
Mouse oral LD50 = 8,500 mg/kg.
Human infant oral TDLo (behavioral) =
2,747 mg/kg.
Probable human oral lethal dose = 5-15
g/kg.
Rat inhalation 4-hour LC50 >2. 1 mg/L
(whole-body inhalation to aerosol)
Lewis, 2000
Lewis, 2000
Lewis, 2000
HSDB, 2003
ECHA, 2013
Reported in a secondary source,
limited study details provided.
Reported in a secondary source,
limited study details provided.
Reported in a secondary source,
limited study details provided.
Reported in a secondary source,
limited study details provided.
No data located.
Reported in a secondary source.
There was no mortality at the
highest dose tested (2.1 mg/L);
conducted according to OECD 403.
LOW: Experimental studies indicate low concern for Carcinogenicity based on results from studies on
magnesium hydroxide and the related magnesium chloride.
5 -week, repeated-dose/carcinogenicity
study, oral (diet), rat; Decreased number
of carcinogen-induced DNA synthesis in
BIBRA, 1993
Structure could not be evaluated by
OncoLogic.
Reported in a secondary source,
limited study details provided; study
duration insufficient as a cancer
4-257
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
the large bowel epithelial cells.
NOAEL: 2,000 ppm (approximately 100
mg/kg-day, highest dose tested)
Combined Chronic
Toxicity/Carcinogenicity
Other
96-week chronic toxicity/carcinogenicity
study on MgCl2, oral, mouse;
no significant differences in tumor
incidence between treated and control
animals except for dose-related decrease
in the incidence of hepatocellular
carcinomas in males.
Kurataetal., 1989
227-day, chronic toxicity/ carcinogenicity
study, oral (diet), rat; decreased number
of colon tumors in rats pretreated with a
known colon carcinogen.
NOAEL: 50 mg/kg-day (highest dose
tested).
BIBRA, 1993
16-week carcinogenicity study, oral (diet),
rat; inhibitory effects on colon
carcinogenesis, carcinogen-induced
expression of c-myc proto-oncogene and
cell proliferation.
NOAEL: 0.2% in diet (highest
concentration tested)
Wangetal., 1993
Inhalation exposure of male rats to short
(4.9x0.31 mm) or long (12x0.44 mm)
MgSO4/5Mg(OH)2'3H2O filaments for 6
hour/day, 5 day/week for up to 1 year did
not increase the incidence of any tumor
types in animals sacrificed 1 day or 1 year
after cessation of exposure.
NAS, 2000
study.
Sufficient study details reported in a
primary source; test substance:
magnesium chloride.
Reported in a secondary source,
limited study details provided; study
duration insufficient as a cancer
study.
Sufficient study details reported in a
primary source; study duration
insufficient as a cancer study.
Reported in a secondary source,
limited study details provided; study
duration insufficient as a cancer
study.
No data located.
4-258
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Genotoxicity
Gene Mutation in vitro
Gene Mutation in vivo
Chromosomal Aberrations in
vitro
Chromosomal Aberrations in
vivo
DNA Damage and Repair
Other
Reproductive Effects
Reproduction/Developmental
Toxicity Screen
DATA
REFERENCE
DATA QUALITY
LOW: Experimental studies indicate that magnesium hydroxide is not mutagenic to bacteria or
mammalian cells in vitro and does not cause chromosomal aberrations in human lymphocytes in vitro.
Negative, Ames Assay in Salmonella and
Escherichia coli.
Negative; mouse lymphoma assay,
L5178Y cells; with and without metabolic
activation.
Negative; did not induce chromosomal
aberrations in human lymphocytes; with
and without metabolic activation.
BIBRA, 1993
ECHA, 2013
ECHA, 2013
Reported in a secondary source,
limited study details provided. Only
3 strains of Salmonella were tested;
current regulatory guidelines
suggest that at least 4 strains be used
in Ames tests.
Reported in a secondary source.
No data located.
Reported in a secondary source.
No data located.
No data located.
No data located.
LOW: There were no reproductive effects observed in rats in a repeated dose toxicity study with the
reproduction/developmental toxicity screen at doses of magnesium hydroxide as high as 1,000 mg/kg-day.
No data located.
4-259
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Reproduction and Fertility
Effects
Other
Developmental Effects
Reproduction/
Developmental Toxicity
Screen
DATA
Repeated dose toxicity study with the
reproduction/developmental toxicity
screen; rat, oral (gavage), 0, 110, 330,
1,000 mg/kg-day magnesium hydroxide.
Males exposed for 29 days: 2 weeks prior
to mating, during mating and up to
termination; females exposed for 41-45
days: 2 weeks premating, during mating,
post coitum, and 4 days of lactation.
There were no reproductive effects
observed in any dose group.
NOAEL: 1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
REFERENCE
ECHA, 2013
DATA QUALITY
Reported in a secondary source.
Study conducted according to
OECD 422.
No data located.
No data located.
LOW: Magnesium hydroxide is expected to be of low concern for developmental effects based on a
nonstandard experimental study indicating magnesium chloride produces no adverse effects on
developmental outcomes at levels up to 96 mg/kg/day of Mg2+ ion and an experimental study from a
secondary source showing no effect on human newborns.
No data located.
4-260
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Repeated dose toxicity study with the
reproduction/developmental toxicity
screen; rat, oral (gavage), 0, 110, 330,
1,000 mg/kg-day. Males exposed for 29
days: 2 weeks prior to mating, during
mating and up to termination; females
exposed for 41-45 days: 2 weeks
premating, during mating, post coitum,
and 4 days of lactation.
There were no developmental effects
observed in any dose group.
NOAEL: 1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
ECHA, 2013
Reported in a secondary source.
Study conducted according to
OECD 422.
Repeated-dose/developmental study (fetal
exposure at unspecified dose levels during
3rd trimester), 27 hypertensive women
treated with magnesium hydroxide, no
effect on newborns except slightly
increased body weight and
hypermagnesiumemia. Cord serum Mg
levels reported to be 70-100% of maternal
levels after treatment (potentially causing
neurological depression in neonate,
characterized by respiratory depression,
muscle weakness, decreased reflexes).
Prolonged magnesium treatment during
pregnancy may be associated with
maternal and fetal hypocalcemia and
adverse effects on fetal bone
mineralization.
HSDB, 2003
Reported in a secondary source,
limited study details provided.
Maternal treatment doses not
specified.
4-261
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Prenatal Development
Postnatal Development
Prenatal and Postnatal
Development
Developmental Neurotoxicity
Other
Neurotoxicity
Neurotoxicity Screening
Battery (Adult)
Other
DATA
10-day (GD 6-15)
reproductive/developmental study on
MgCl2, oral, rat; no treatment-related
effects.
NOAEL: 96 mg/kg-day for Mg 2+ ion
(highest dose tested)
LOAEL: Not established
REFERENCE
NAS, 2000
DATA QUALITY
Reported in a secondary source,
limited study details provided.
No data located.
No data located.
No data located.
No data located.
LOW: Magnesium hydroxide is expected to be of low hazard for neurotoxicity based on expert judgment.
Low potential for neurotoxicity.
(Estimated)
Expert judgment
Estimated based on expert
judgment.
No data located.
4-262
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Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Repeated Dose Effects
LOW: Experimental studies indicate magnesium ions produce no adverse systemic effects in rats or mice
at levels > 1,000 mg/kg-day of magnesium hydroxide.
96-week repeated-dose study for MgCl2,
oral (0, 0.5, 2% in the diet), mouse;
decreased body weight gain, increased
food/water consumption and increased
relative brain, heart and kidney weights in
high dose (2%) females, no effects in
males.
Female:
NOAEL: 87 mg/kg-day for Mg
LOAEL: 470 mg/kg-day for Mg2+
2+ ion
ion
Male:
NOAEL: 336 mg/kg-day for Mg2
(highest dose tested)
LOAEL: Not established
ion
90-day repeated-dose study for MgQ2,
oral, mouse (M: 73, 146, 322, 650, 1,368
mg/kg-day for Mg2+ ion; F: 92, 190, 391,
817, 1,660 mg/kg-day for Mg2+ ion);
decreased body weight gain in males and
females at highest dose tested (1,660
mg/kg-day); renal tubular vacuolation in
males administered 650 mg/kg-day for
Mg2+ ion.
Female:
NOAEL: 817 mg/kg-day for Mg2+ ion
LOAEL: 1,660 mg/kg-day for Mg2+ ion
Male:
NOAEL: 322 mg/kg-day for Mg2+ ion
LOAEL: 650 mg/kg-day for Mg2+ ion
90-day repeated-dose study in B6C3F1
mice; MgCl2 administered orally at doses
4-263
Kurataetal., 1989
NAS, 2000
NAS, 2000
Adequate, primary source.
Reported in a secondary source, no
study details provided.
Reported in a secondary source, no
study details provided.
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
DATA
of 0.3, 0.6, 1.25 and 2. 5% in the diet.
Effects included decreased body weight
gain and renal tubular vacuolation in
males in the high-dose group (840 mg/kg-
day).
Female:
NOAEL: 587 mg/kg-day for Mg2+ ion
Male:
NOAEL: 420 mg/kg-day for Mg2+ ion
LOAEL: 840 mg/kg-day for Mg2+ ion
32-week repeated-dose study, diet, rat; no
effects on body weight or liver weight.
NOAEL: 1,000 ppm (approximately 50
mg/kg-day, highest dose tested)
LOAEL: Not established
Repeated dose toxicity study with the
reproduction/developmental toxicity
screen; rat, oral (gavage), 0, 110, 330,
1,000 mg/kg-day MgOH2. Males exposed
for 29 days: 2 weeks prior to mating,
during mating and up to termination;
females exposed for 41-45 days: 2 weeks
premating, during mating, post coitum,
and 4 days of lactation.
There were no lexicologically relevant
changes in any of the parental parameters
examined.
NOAEL: 1,000 mg/kg-day (highest dose
tested)
LOAEL: Not established
4-week repeated-dose study, oral, human;
caused diarrhea, abdominal discomfort,
REFERENCE
BIBRA, 1993
ECHA, 2013
BIBRA, 1993
DATA QUALITY
Reported in a secondary source, no
study details provided.
Reported in a secondary source.
Study conducted according to
OECD 422.
Reported in a secondary source, no
study details provided.
4-264
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
and increased serum magnesium levels.
NOAEL: Not established
LOAEL: 400 mg/kg-day (only dose
reported)
Inhalation exposure of male rats to short
(4.9x0.31 mm) or long (12x0.44 mm)
MgSO4/5Mg(OH)23H2O filaments for 6
hour/day, 5 day/week for up to 1 year
(concentration not specified) exhibited a
slight increase in the incidence of
pulmonary lesions 1 year after cessation
of exposure. Histopathological
examination revealed a slight increase in
segmental calcification of the pulmonary
artery and thickening of the lung pleura in
rats exposed to both short and long
filaments for 4 weeks or 1 year. There
were no effects on survival or body, lung,
liver, kidney and spleen weights of
animals sacrificed 1 day or 1 year
following a 1-year exposure period.
NAS, 2000
Reported in a secondary source, no
study details provided.
Human systemic effects: chlorine level
changes, coma, somnolence in a neonate.
Lewis, 2000
A case study of intoxication after
oral exposure to magnesium in a
neonate. Reported in a secondary
source; no study details provided.
Repeated oral exposure in humans may
cause rectal stones composed of
magnesium carbonate and magnesium
hydroxide (rare occurrence).
IUCLID, 2000
Reported in a secondary source, no
study details provided.
4-265
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Skin Sensitization
Skin Sensitization
Respiratory Sensitization
[Respiratory Sensitization
Eye Irritation
Eye Irritation
DATA
REFERENCE
DATA QUALITY
LOW: A mouse local lymph node assay (LLNA) reported some Sensitization following exposure to
Mg(OH)2 (purity not reported), while negative results for Sensitization were reported in guinea pigs in a
maximization test. Magnesium hydroxide is not expected to cause skin Sensitization based on professional
judgment. Based on the weight-of-evidence (WOE), a hazard designation of Low is appropriate.
Not sensitizing in a modified Magnusson
and Kligman maximization test in Guinea
pigs; phase 1 induction: administered
intra-dermally at a concentration of 5%
v/v in 0.5% methyl cellulose; phase 2
induction: topically administered at a
concentration of 25% in petrolatum;
challenged: topical application of 25% in
petrolatum; no reaction was observed in
any treated animal in the challenge phase.
Sensitizing in a mouse local lymph node
assay (LLNA); application of 10, 25 or
50% w/w MgOH2 in propylene glycol to
the ears. Very slight erythema in all
animals treated with 50% MgOH2,
staining on the ears at 10, 25 and 50%. SI
(stimulation index) at 10, 25 and 50% was
2.0, 3.6 and 5.9, respectively. Dose
response and ECS value >/= 3.
Does not cause skin Sensitization.
(Estimated)
Submitted confidential study
ECHA, 2013
Professional judgment
Test substance identified as
Mg(OH)2; purity not reported;
negative and positive controls were
used.
Well documented secondary source;
GLP study conducted according to
guidelines. MgOH2, purity not
stated
Estimated by professional judgment.
No data located.
No data located.
MODERATE: Based on irritation and damage to the corneal epithelium in rabbits that cleared within 2-3
days.
Moderately irritating to rabbit eyes.
Administration of milk of magnesia twice
a day for 3-4 days caused damage to
corneal epithelium of rabbit eyes;
IUCLID, 2000
HSDB, 2003
Reported in a secondary source,
limited study details provided.
Reported in a secondary source,
limited study details provided. Milk
of magnesia is a mixture containing
4-266
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Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Dermal Irritation
Dermal Irritation
Endocrine Activity
Immunotoxicity
Immune System Effects
DATA
however, effects disappeared within 2-3
days.
REFERENCE
DATA QUALITY
magnesium hydroxide and inactive
ingredients.
LOW: An experimental study indicates that magnesium hydroxide is not an irritant to rabbit skin.
Moderate potential for dermal irritation
based on experimental aqueous pH
values.
(Estimated)
Not corrosive in an in vitro human skin
corrosion test.
Not irritating in an in vitro skin irritation
test.
Not irritating, rabbits.
Expert judgment
ECHA, 2013
ECHA, 2013
Submitted confidential study
Estimated based on expert
judgment.
Reported in a secondary source.
Study conducted according to
OECD guideline 431.
Reported in a secondary source. In
vitro skin irritation: reconstructed
human epidermis model test.
Reported in a submitted confidential
study.
No data located.
No data located.
Magnesium hydroxide is expected to have low potential for immunotoxicity based on expert judgment.
Low potential for immunotoxicity.
(Estimated)
Expert judgment
Estimated based on expert
judgment.
ECOTOXICITY
ECOSAR Class
Acute Aquatic Toxicity
Fish LC50
Not applicable
LOW: Estimated LC50 values for all of the standard toxicity test organisms are greater than 100 mg/L.
Experimental LC50 values are much greater than the anticipated water solubility, suggesting no effects at
saturation (NES).
96-hour LC50 =
MgCl2:2,120mg/L
MgSO4: 2,820 mg/L
(Estimated)
Mount etal., 1997
Estimated based on analogy to
MgCl2 and MgSO4; expected to
display NES because this amount of
test substance is not anticipated to
dissolve in water at a concentration
at which adverse effects may be
expressed.
4-267
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Daphnid LC50
Green Algae EC50
Chronic Aquatic Toxicity
Fish ChV
DATA
Pimephalis promelas 96-hour LC50 = 511
mg/L; static conditions.
(Experimental)
Onchorinchus mykiss 96-hour LC50 =
775.8 mg/L; static conditions.
(Experimental)
Daphnia magna 48-hour LC50 =
MgCl2: 1,330 mg/L
MgSO4: 1,820 mg/L
(Estimated)
Daphnia magna 48-hour LC50 = 284.76
mg/L; static conditions.
(Experimental)
Gammarus lacustris LC50 = 64.7 mg/L.
(Experimental)
Scenedesmus subspicatus and
Selenastrum capricornutum 72-hour EC50
>100 mg/L (for growth and biomass).
(Experimental)
REFERENCE
ECHA, 2013
ECHA, 2013
Biesinger and Christensen,
1972; Mount etal., 1997
ECHA, 2013
O'Connell et al., 2004
ECHA, 2013
DATA QUALITY
Reported in a secondary source.
Test material diluted to 61% in
aqueous suspension.
Reported in a secondary source.
Test material diluted to 61% in
aqueous suspension.
Estimated based on analogy to
MgCl2 and MgSO4; expected to
display NES because this amount of
test substance is not anticipated to
dissolve in water at a concentration
at which adverse effects may be
expressed.
Reported in a secondary source.
Test material diluted to 61% in
aqueous suspension.
Reported in a secondary source,
study details and test conditions
were not provided. Not a standard
test species.
Reported in a secondary source.
LOW: Estimated chronic values (ChV) are all >10 mg/L and exceed the anticipated water solubility,
suggesting NES.
Fish ChV: 50-80 mg/L
(Experimental)
Freshwater fish ChV = 403 mg/L.
ECHA, 2013
Professional judgment
An acute to chronic ratio of 10 was
applied to experimental acute data
for Pimephalis promelas and
Onchorinchus mykiss. Reported in a
secondary source. Test material
diluted to 61% in aqueous
suspension.
Estimated using an acute to chronic
4-268
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Daphnid ChV
Green Algae ChV
DATA
(Estimated)
Daphnia ChV = 82 mg/L
(Estimated)
Green algae NOEC: 980 mg/L
LOEC: 1,230 mg/L
(Estimated)
REFERENCE
Suter, 1996
ECOTOX, 2012
DATA QUALITY
ratio of 3:3; expected to display
NES because this amount of test
substance is not anticipated to
dissolve in water at a concentration
at which adverse effects may be
expressed.
Estimated based on analogy to the
measured ChV for Mg2+ ion; based
on tests that were not standard but
were judged to be of good quality;
expected to display NES because
this amount of test substance is not
anticipated to dissolve in water at a
concentration at which adverse
effects may be expressed.
Estimated based on analogy to
MgSO4; expected to display NES
because this amount of test
substance is not anticipated to
dissolve in water at a concentration
at which adverse effects may be
expressed.
ENVIRONMENTAL FATE
Transport
Henry's Law Constant (atm-
m3/mole)
Sediment/Soil
Adsorption/Desorption - Koc
Level III Fugacity Model
The low water solubility, the estimated vapor pressure of 30,000 and
estimated Henry's Law constant of 30,000 (Estimated)
Professional judgment
EPA, 2004; Professional
judgment
Cutoff value for nonvolatile
compounds.
Cutoff value fornonmobile
compounds.
Not all input parameters for this
model were available to run the
estimation software (EPI).
4-269
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Persistence
Water
Soil
Air
Reactivity
Aerobic Biodegradation
Volatilization Half-life for
Model River
Volatilization Half-life for
Model Lake
Aerobic Biodegradation
Anaerobic Biodegradation
Soil Biodegradation with
Product Identification
Sediment/Water
Biodegradation
Atmospheric Half-life
Photolysis
Hydrolysis
DATA
REFERENCE
DATA QUALITY
HIGH: As an inorganic compound, magnesium hydroxide is not expected to biodegrade, oxidize in air, or
undergo hydrolysis under environmental conditions. Magnesium hydroxide does not absorb light at
environmentally relevant wavelengths and is not expected to photolyze. Magnesium hydroxide is
recalcitrant and it is expected to be found in the environment >180 days after release. As a naturally
occurring compound, it may participate in natural cycles and form complexes in environmental waters.
Recalcitrant (Estimated)
>1 year (Estimated)
>1 year (Estimated)
Recalcitrant (Estimated)
Recalcitrant (Estimated)
>1 year (Estimated)
Not a significant fate process (Estimated)
Not a significant fate process (Estimated)
Professional judgment
Professional judgment
Professional judgment
Professional judgment
Professional judgment
Professional judgment
Professional judgment
Professional judgment
Substance is or contains inorganic
elements, such as metal ions or
oxides, that are expected to be found
in the environment >180 days after
release.
Based on the magnitude of the
estimated Henry's Law constant.
Based on the magnitude of the
estimated Henry's Law constant.
This inorganic compound is not
amenable to available estimation
methods.
This inorganic compound is not
amenable to available estimation
methods.
No data located.
No data located.
Substance does not contain
functional groups amenable to
atmospheric degradation processes.
Magnesium hydroxide does not
absorb UV light at environmentally
relevant wavelengths and is not
expected to undergo photolysis.
Substance does not contain
functional groups amenable to
hydrolysis.
4-270
-------
Magnesium Hydroxide CASRN 1309-42-8
PROPERTY/ENDPOINT
Environmental Half-life
Bioaccumulation
Fish BCF
Other BCF
BAF
Metabolism in Fish
DATA
REFERENCE
DATA QUALITY
Not all input parameters for this
model were available to run the
estimation software (EPI).
LOW: Magnesium hydroxide is not expected to bioaccumulate based on professional judgment.
<100 (Estimated)
<100 (Estimated)
Professional judgment
Professional judgment
This inorganic compound is not
amenable to available estimation
methods.
No data located.
This inorganic compound is not
amenable to available estimation
methods.
No data located.
ENVIRONMENTAL MONITORING AND BIOMONITORING
Environmental Monitoring
Ecological Biomonitoring
Human Biomonitoring
Magnesium hydroxide is a mineral that occurs naturally in the environment (HSDB, 2003).
No data located.
This chemical was not included in the NHANES biomonitoring report (CDC, 2013).
4-271
-------
Aldrich Chemical Company (2006) 2007-2008 Handbook of fine chemicals. Milwaukee, WI: Aldrich Chemical Company.
BIBRA (1993) Toxicity profile: Magnesium hydroxide.
Biesinger KE and Christensen GM (1972) Effects of various metals on survival, growth, reproduction, and metabolism ofDaphnia magna. J Fish
Res Board Can 29(12): 1691-1700.
CDC (2013) Fourth national report on human exposure to environmental chemicals, updated tables, March 2013.
http://www.cdc.gov/exposurereport/pdf/FourthReport_UpdatedTables_Mar2013.pdf
ECFiA (2013) Magnesium hydroxide. Registered substances. European Chemicals Agency.
http://apps.echa.europa.eu/registered/data/dossiers/DISS-9ea79197-lfe4-5688-e044-00144f67d031/AGGR-b7f868f3-337e-48ac-8f47-
d5d7445c8973_DISS-9ea79197-lfe4-5688-e044-00144f67d031.html#L-9adf9459-3347-4fcc-blc9-47f4c891001f
ECOTOX (2012) ECOTOX database. U.S. Environmental Protection Agency, http://cfpub.epa.gov/ecotox/.
EPA (1999) Determining the adequacy of existing data. High Production Volume (HPV) Challenge. Washington, DC: U.S. Environmental
Protection Agency, http://www.epa.gov/hpv/pubs/general/datadeqfn.pdf
EPA (2004) Pollution prevention (P2) framework. Washington, DC: U.S. Environmental Protection Agency, Office of Pollution Prevention and
Toxics, http://www.epa.gov/oppt/sf/pubs/p2frame-june05a2.pdf
ESIS (2011) European chemical Substance Information System. European Commission, http://esis.jrc.ec.europa.eu/.
HSDB (2003) Magnesium hydroxide. Hazardous Substances Data Bank. National Library of Medicine, http://toxnet.nlm.nih.gov/cgi-
bin/sis/htmlgen?HSDB.
Hodgman CD (1959) In: Hodgman CD, eds. CRC handbook of chemistry and physics. Cleveland, OH: Chemical Rubber Publishing Company.
IUCLID (2000) Dataset for magnesium hydroxide. International Uniform Chemical Information Database.
Kurata Y, Tamano S, Shibata MA, et al. (1989) Lack of carcinogenicity of magnesium chloride in a long-term feeding study in B6C31 mice. Food
Chem Toxicol 27(9):559-563.
Lewis RJ Sr (1997) Hawley's condensed chemical dictionary. New York, NY: John Wiley & Sons, Inc.:691.
Lewis RL (2000) Sax's dangerous properties of industrial materials. New York, NY: John Wiley & Sons, Inc.
4-272
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Lide DR (2000) 2000-2001 CRC handbook of chemistry and physics. 81st ed. Boca Raton, FL: CRC Press.
Mount DR, Gulley DD, Hockett JR, et al. (1997) Statistical models to predict the toxicity of major ions to Ceriodaphnia Dubia, Daphnia Magna
and Pimephales Promelas (Fathead minnows). Environ Toxicol Chem 16(10):2009-2019.
NAS (2000) Table 7-2 Selected oral animal toxicity data on magnesium hydroxide. National Academies Press.
http://www.nap.edu/openbook.php?record_id=9841&page=139#p2000a45a9960139001 (accessed June 23, 2008).
O'Connell D, Whitley A, Burkitt J, et al. (2004) DfE Phase II Rev 0.6. Scottsdale, AZ: HDP User Group International, Inc.
http://www.dell.com/downloads/global/corporate/environ/HDPUG_DfE_2.pdf
O'Neil M, Heckelman PE, Koch CB, et al. (2011) e-Merck index Basic Search. Whitehouse Station, NJ: Merck & Co.
https://themerckindex.cambridgesoft.com/TheMerckIndex/index.asp.
Suter GW (1996) Toxicological benchmarks for screening contaminants of potential concern for effects on freshwater biota. Environ Toxicol
Chem 15(7): 1232-1241.
Wang A, Yoshimi N, Tanaka T, et al. (1993) Inhibitory effects of magnesium hydroxide on c-myc expression and cell proliferation induced by
methylazoxymethanol acetate in rat colon. Cancer Lett 75:73-78.
4-273
-------
Melamine Polyphosphate
VL = Very Low hazard L = Low hazard = Moderate hazard H = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion
by-products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the
table.
¥ Aquatic toxicity: EPA/DfE criteria are based in large part upon water column exposures which may not be adequate for poorly soluble substances such as many flame retardants
that may partition to sediment and particulates.
Chemical
CASRN
Human Health Effects
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Melamine Polyphosphate
15541-60-3 | L \M\M\H\M\M\M\L\
VL L
Hazard designations are based upon the component of the salt with the highest hazard designation, including the corresponding free acid or base.
4-274
-------
Melamine Polyphosphate
H
H*NYNVNh2 ° °
^ 0" " OH
NH2
CASRN: 15541-60-3
MW: >1,000
MF: C3H6N6 (H3PO4)n
Physical Forms:
Neat: Solid
Use: Flame retardant
SMILES: n(c(nc(nl)N)N)clN(H)(H)OP(=O)(O)OP(=O)(O)O (n =1) SMILES for the representative structure was created using the methodology described in the
EPI help file.
Synonyms: Diphosphoric acid, compound with l,3,5-triazine-2,4,6-triamine; Polyphosphoric acids, compounds with melamine.
The CASRN for the compound melamine pyrophosphate is 15541-60-3. The CASRN 218768-84-4 is associated with the product Melapur 200, not the chemical
melamine polyphosphate.
Chemical Considerations: This alternative contains a polymeric moiety. Although the chain length of the polyphosphoric acid is not specified, the smaller, water-
soluble polyphosphate ions were used in assessment (generally as the diphosphate ion, n=l). Melamine polyphosphate will freely dissociate under environmental
conditions based on professional judgment. Measured values from studies on the dissociated components were used to supplement data gaps as appropriate and EPI v
4.10 was used to estimate physical/chemical and environmental fate values in the absence of experimental data. Measured values from experimental studies were
incorporated into the estimations.
Polymeric: Yes
Oligomeric: Melamine polyphosphate is a complex mixture consisting of melamine and polyphosphate chains of varying length.
Metabolites, Degradates and Transformation Products: Melamine (CASRN 108-78-1)
Analog: Confidential structurally similar polymers; Polyphosphoric acid (CASRN Analog Structure:
8017-16-1) and melamine (CASRN 108-78-1) are the dissociated components of
this salt
Endpoint(s) using analog values: Reproductive effects, neurotoxicity,
immunotoxicity
H N N NH O O
~>^ M^ II II
^f OH " OH
2 Polyphosphoric acid
Melamine (CASRN 8017-16-1)
(CASRN 108-78-1)
4-275
-------
Structural Alerts: Aromatic amine, genetic toxicity (EPA, 2012).
Risk Phrases: Not classified by Annex I Directive 67/548/European Economic Community (EEC) & IUCLID (Pakalin et al., 2007).
Hazard and Risk Assessments: Australian Safety and Compensation Council National Industrial Chemicals Notification and Assessment Scheme (NICNAS),
October 30, 2006 (Australia, 2006).
4-276
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
Water Solubility (mg/L)
Log Kow
Flammability (Flash Point)
Explosivity
Pyrolysis
pH
>400 (Measured)
>400 (Measured)
>300
(Estimated)
225
Decomposes
Reported for activated melamine
pyrophosphate (CASRN 15541-60-3)
(Measured)
<10'8
(Estimated)
20,000 (Measured)
20,000 (Measured)
<-2
(Estimated)
Not highly flammable (Measured)
Not a potential explosive (Measured)
Not a potential explosive (Measured)
May produce carbon monoxide,
ammonia, oxides of nitrogen, and oxides
of phosphorus by thermal decomposition.
Reported for activated melamine
pyrophosphate (CASRN 15541-60-3).
(Estimated)
7 Reported for activated melamine
pyrophosphate (CASRN 15541-60-3)
(Measured)
Submitted confidential study
Australia, 2006
EPI v4.10; Professional
judgment
New Line Safety, 2011
EPIv4.10;Boethlingand
Nabholz, 1997
Submitted confidential study
Australia, 2006
EPIv4.10
Submitted confidential study
Australia, 2006
Submitted confidential study
New Line Safety, 2011
New Line Safety, 2011
Adequate; value for the melamine
polyphosphate salt.
Adequate; value for the melamine
polyphosphate salt.
As an organic salt, it is expected to
decompose before boiling.
No study details reported in an
MSDS.
Cutoff value for nonvolatile
compounds.
Adequate; value for the melamine
polyphosphate salt.
Adequate.
Cutoff value for highly water soluble
substances.
Reported in a secondary source and
based on its use as a flame retardant.
Adequate.
Adequate.
No study details reported in an
MSDS.
No study details reported in an
MSDS.
4-277
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
pKa
Particle Size
DATA
Pyrophosphoric Acid:
pKal = 0.85
pKa2 = 1.96
pKa3 = 6.78
pKa4 = 10.39 (Estimated)
Melamine: pKM= 7.3;
pKb2=11.4
according to OECD 112 (Measured)
Melamine: pKM = 9
There are several amino groups that result
in basic properties. pKH = 9
pKb2 = 14
Kbi= l.lxlO'9
Kb2 = l.OxlO-14 at 25°C (Measured)
Melamine:
pKbl = 9
pKb2 = 14
Kbi= l.lxlO'9
Kb2 = l.OxlO-14 at 25°C (Measured)
Melamine: Considered a weak base
Neutral at pH values of 6 to 13;
Cation formation at the triazine ring
nitrogen at pH values of 1 to 4
(Measured)
Melamine: 5 (Measured)
REFERENCE
ECHA,2014
ECHA,2013
Baynes et al., 2008
Crews et al., 2006
OECD SIDS, 1998
HSDB, 2008; Weber, 1970
DATA QUALITY
Reported for pyrophosphoric acid
(CASRN 2466-09-3); study reported
in a secondary source.
Guideline study reported for
melamine in a secondary source.
Reported from a nonguideline study
for melamine.
For melamine; study details were not
available.
Supporting information provided in
a secondary source for melamine.
Reported in a secondary source for
melamine, value is assumed to be
the pKb .
No data located.
HUMAN HEALTH EFFECTS
4-278
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Toxicokinetics
Dermal Absorption in vitro
Absorption,
Distribution,
Metabolism
& Excretion
Oral, Dermal or Inhaled
DATA
REFERENCE
DATA QUALITY
No toxicokinetic data were located for melamine polyphosphate or polyphosphoric acid; limited data for
melamine indicate that melamine was rapidly absorbed, distributed to body fluids, cleared from plasma
and excreted mainly via urine in monkeys. In rats, melamine was distributed to the stomach, small
intestine, cecum, and large intestine, and found in blood and urine. Following a single oral exposure to
pregnant rats, melamine was detected in the maternal serum, breast milk, whole foetus, amniotic fluid,
neonatal serum and neonatal kidney. There is evidence that Melamine passed through the placenta,
reached the fetus and accumulated in the lactating mammary gland. Excretion occurred through the
placenta of the fetus and the kidneys of neonates and was later excreted into amniotic fluid. Melamine was
transferred quickly to fetal circulation in studies where placentas from mothers following caesarean
section or normal delivery were perfused with melamine. Melamine was readily cleared by the kidney in
pigs administered melamine intravenously; distribution may be limited to the extracellular fluid
compartment. There was no concern for binding in tissues. The half-life was reported as 4.04 hours. In
monkeys, the half-life in plasma was ~4.41 hours. Other data for the melamine indicate an elimination
phase half-life of 2.7 hours from plasma and 3 hours for urine.
Melamine: Distributed to stomach, small
intestine, cecum, and large intestine, and
found in blood, and urine of rats.
Melamine: The elimination phase half-
life calculated from plasma data was 2.7
hours, and the urinary half-life was 3.0
hours. The renal clearance was
determined to be 2.5 mL/minute.
(Measured)
Melamine polyphosphate: Low for all
routes (Estimated)
Rhesus monkeys were orally
administered melamine at a single dose of
1.4 mg/kg bw. Melamine was rapidly
absorbed, distributed to body fluids,
rapidly cleared from plasma and excreted
mainly via urine. The half-life in plasma
was -4.41 hours. There was no
correlation (concentration-time curve in
plasma and urine) between melamine and
ECHA,2011b
Mastetal., 1983
Professional judgment
Liu etal., 2010
Study details reported in a secondary
source.
For melamine; adequate,
nonguideline study.
Estimates based on
physical/chemical properties.
Adequate, primary source
4-279
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
cyanuric acid, suggesting that melamine
may not be metabolized to cyanuric acid
in vivo.
Pregnant Sprague-Dawley rats were
administered a single oral dose of
melamine (-6-1 mg in <2 ml water) on
gestation day 17. Melamine was also
administered to neonates at postnatal day
14 (-0.3-0.6 mg in <0.2 ml in water).
Melamine was detected in the maternal
serum, breast milk, whole foetus,
amniotic fluid, neonatal serum and
neonatal kidney. This is evidence that
Melamine passed through the placenta,
reached the fetus and accumulated in the
lactating mammary gland. Excretion
occurred through the placenta of the fetus
and the kidneys of neonates and was later
excreted into amniotic fluid.
Chuetal., 2010
Adequate primary source
Other
Pigs (5 weanling) were administered
Melamine intravenously at a dose of 6.13
mg/kg.
Melamine is readily cleared by the
kidney; distribution may be limited to the
extracellular fluid compartment. No
concern for binding in tissues.
Half-life: 4.04 hours; clearance: 0.11
L/h/kg; volume distribution: 0.61 L/kg.
Baynes et al., 2008
Adequate primary source
Placentas from mothers following
caesarean section or normal delivery were
perfused with 0 mM or 1 mM melamine,
or 10 mM melamine with 10 nM cyanuric
acid (CYA). Melamine (34-45%) was
transferred quickly to fetal circulation
(0.12-1.34% within 5 minutes, 34%
within 4 hours); addition of CYA had no
Partanen et al., 2012
Adequate, primary study
4-280
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Acute Mammalian Toxicity
Acute
Lethality
Oral
DATA
effect. Functionality of the placental
tissue was not affected. Viability of
BeWo cells was decreased. It is
concluded that melamine may be
fetotoxic.
REFERENCE
DATA QUALITY
LOW: Melamine polyphosphate is expected to be of low hazard for acute toxicity based on experimental
evidence for melamine polyphosphate, phosphoric acids and melamine with LDSOs > 1,000 mg/kg
following oral and dermal exposure. One inhalation study reported an LC50 of 3.25 mg/L; however, the
reported study details were too limited to consider for the hazard designation.
Melamine polyphosphate: Rat (Gavage)
LD50 >2,000 mg/kg
Melamine polyphosphate: Rat LD50
>2,000 mg/kg
Melamine polyphosphate: Rat (Gavage)
LD50 >2,000 mg/kg
Melamine polyphosphate: Rat LD50
>2,000 mg/kg
Polyphosphoric acid: LD50 = 4,000
mg/kg (species unknown)
Melamine: Rat LD50 = 3,161 mg/kg
(male), 3,828 mg/kg (females)
Melamine: Mouse LD50 = 3,296 mg/kg
(male), 7,014 mg/kg (female)
Melamine: Mouse LD50 = 4,550 mg/kg
Melamine: Rat LD50 = 3,160 mg/kg
(male) and 3,850 mg/kg (female)
Melamine: Rat LD50 >6,400 mg/kg
Ciba, 2005 (as cited in Australia,
2006)
NOTOX BV, 1998 (as cited in
Australia, 2006)
Submitted confidential study
Submitted confidential study
ARZNAD, 1957
NTP, 1983b;Melnicketal.,
1984
NTP, 1983b;Melnicketal.,
1984
American Cyanamid Company,
1955; May, 1979; Trochimowicz
etal., 2001
Trochimowicz et al., 2001
BASF, 1969 (as cited in OECD
SIDS, 1999; IUCLID, 2000a)
Sufficient study details reported.
Limited study details reported.
Study details reported in a
confidential study.
Limited study details reported in a
confidential study.
Limited study details reported. The
test substance was identified as
polyphosphates, and was described
as containing 1/3 Kurrol's potassium
salt and 2/3 pyrophosphate.
Sufficient study details reported.
Sufficient study details reported.
Limited study details reported.
Limited study details reported.
Limited study details reported.
4-281
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Dermal
Inhalation
Carcinogenicity
OncoLogic Results
Carcinogenicity (Rat and Mouse)
DATA
Melamine: LD50 ~ 4,800 mg/kg
Melamine: Rabbit LD50 >1,000 mg/L
Melamine: Rat LC50 = 3.25 mg/L
REFERENCE
Hoechst, 1963 (as cited in
IUCLID, 2000a)
Unknown, 1990
Ubaidullajev, 1993 (as cited in
IUCLID, 2000a)
DATA QUALITY
Limited study details reported.
Limited study details reported.
Limited study details reported in a
secondary source.
MODERATE: Estimated based on the dissolution product melamine. There is experimental evidence that
oral melamine exposure to high doses of melamine causes Carcinogenicity in animals. However, there is no
evidence for Carcinogenicity to humans. In addition, Oncologic estimated a marginal concern that is
consistent with a Moderate hazard designation using DfE criteria. Tumor formation in animals appeared
to be due to mechanical irritation by bladder calculi/stones. IARC classifies melamine as Group 3: not
classifiable as to its Carcinogenicity to humans.
Melamine: Marginal (Estimated)
Melamine: Group 3: melamine is not
classifiable as to its Carcinogenicity to
humans; there is inadequate evidence in
humans for the Carcinogenicity of
melamine, and there is sufficient evidence
in experimental animals for the
Carcinogenicity of melamine under
conditions in which it produces bladder
calculi.
Melamine: Significant formation of
transitional cell carcinomas in the urinary
bladder of male rats and significant
chronic inflammation in the kidney of
dosed female rats were observed.
Carcinoma formation was significantly
correlated with the incidence of bladder
stones. A transitional -cell papilloma was
observed in the urinary bladder of a single
high dose male rat, and compound related
lesions were observed in the urinary tract
of dosed animals.
Melamine: Increased incidence of acute
and chronic inflammation and epithelial
OncoLogic, 2008
IARC, 1999
NTP, 1983b; Huff, 1984;
Melnick et al., 1984
NTP, 1983b; Huff, 1984;
Melnick et al., 1984
IARC classification statement.
Sufficient study details reported.
Sufficient study details reported.
4-282
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
hyperplasia of the urinary bladder was
observed in male mice. Bladder stones
and compound-related lesions were
observed in the urinary tract of test
animals. Melamine was not considered
carcinogenic.
Melamine: Melamine-induced
proliferative lesions of the rat urinary
tract were directly due to the irritant
stimulation of calculi, and not to
molecular interactions between melamine
or its metabolites with the bladder
epithelium.
Okumura et al, 1992
Sufficient study details reported.
Melamine: Water intake, used as an
index of urinary output, was increased by
NaCl treatment. Calculus formation
resulting from melamine administration
was suppressed dose-dependently by the
simultaneous NaCl treatment. The main
constituents of calculi were melamine and
uric acid (total contents 61.1- 81.2%).
The results indicate that melamine-
induced proliferative lesions of the
urinary tract of rats were directly due to
the irritation stimulation of calculi, and
not molecular interactions between
melamine itself or its metabolites with the
bladder epithelium.
Ogasawara et al., 1995
Sufficient study details reported.
Melamine: As an initiator, melamine
caused no significant increase in
papillomas per mouse when compared to
controls.
Perrella and Boutwell, 1983
Nonguideline study.
Melamine: Diffuse papillary hyperplasia
of the bladder epithelium and bladder
calculi were observed in all melamine
treated rats. Elevated
4-283
Matsui-Yuasi et al., 1992
Nonguideline study.
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Combined Chronic
Toxicity/Carcinogenicity
Other
Genotoxicity
Gene Mutation in vitro
DATA
spermidine/spermine N 1 -acetyltransferase
activity following melamine treatment
was considered to be an indicator of cell
proliferation.
Melamine: Decreased antitumor activity
was correlated with increasing
demethylation; melamine was considered
inactive as an antitumor drug.
Melamine: In an in vitro cytotoxicity
study in cultured ADJ/PC6 plasmacytoma
ascites tumor cells, the ID50 was 470
(ig/mL after 72 hours of treatment.
Melamine: No effects were observed in
rats fed 1,000 ppm of melamine. 4 of the
10 rats fed 10,000 ppm melamine had
bladder stones associated with the
development of benign papillomas.
Melamine: Increased incidence of
urinary bladder stones (6/20 rats) was
noted in the 10,000 ppm dose group, and
was associated with an increase in benign
papillomata. The NOAEL was
determined to be 1,000 ppm (67 mg/kg-
day).
REFERENCE
Rutty and Connors, 1977
Rutty and Abel, 1980
Anonymous, 1958 (as cited in
Wolkowski Tyl and Reel, 1992)
American Cyanamid Company,
1955
DATA QUALITY
Limited study details reported.
Limited study details reported.
Limited study details reported.
Limited study details reported.
No data located.
MODERATE: Melamine polyphosphate is estimated to be a moderate hazard for genotoxicity based on a
weight of evidence from multiple studies for melamine. For melamine, positive results were observed for in
vivo chromosome aberration and sister chromatid exchange assays conducted by National Toxicology
Program (NTP) in 1988 and 1989. Available in vitro genotoxicity testing was conducted with metabolic
activation systems from the liver. NTP suggests this may not account for potential activation from bladder
epithelial cells, which is the target organ. Proposed genotoxicity testing using a metabolic activation system
from bladder epithelial cells (NTP, 1983) was never conducted (Personal Communication, 2007; 2008).
Melamine: Bacterial forward mutation
assay: Negative with and without liver
activation
Haworth et al., 1983; NTP,
1983a
Sufficient study details reported.
4-284
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Gene Mutation in vivo
Chromosomal Aberrations in vitro
Chromosomal Aberrations in vivo
DATA
Melamine: Bacterial forward mutation
assay: Negative
Melamine: Bacterial reverse mutation
assay: Negative with and without liver
activation
Melamine: Bacterial reverse mutation
assay: Negative with and without
unspecified metabolic activation
Melamine: In vitro mouse lymphoma
test: Negative with and without liver
activation
Melamine: Chinese hamster ovary
(CHO) cells/hypoxanthine-guanine
phosphoribosyl-transferase forward
mutation assay: Negative with and
without liver activation.
Melamine: In vitro chromosomal
aberrations test: Negative in CHO with
and without liver activation.
Melamine: In vitro sister chromatid
exchange assay: Negative in CHO with
and without liver activation.
Melamine: In vitro sister chromatid
exchange assay: Negative in CHO with
and without liver activation.
Melamine: In vivo mouse micronucleus
test: The initial test gave a positive trend
(P = 0.003) for chromosomal damage;
however, both peripheral blood smears
and the repeat bone marrow test were
negative. The overall conclusion was that
melamine does not induce chromosomal
damage.
REFERENCE
Seiler, 1973
Lusbyetal., 1979
Mastetal., 1982b
NTP, 1983a; McGregor et al.,
1988
Mastetal., 1982b
NTP, 1983a; Galloway et al.,
1987
NTP, 1983a; Galloway et al.,
1987
Mastetal., 1982b
NTP, 1983b; Shelby et al., 1993
DATA QUALITY
Limited study details reported.
Limited study details reported.
Limited study details reported.
Sufficient study details reported.
Limited study details reported.
No data located.
Sufficient study details reported.
Sufficient study details reported
Limited study details reported.
Sufficient study details reported.
4-285
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DNA Damage and Repair
Other
DATA
Melamine: In vivo mouse micronucleus
test: Negative
Melamine: In vivo chromosome
aberrations test in mice: Positive
Melamine: In vivo sister chromatid
exchange assay in mice: Positive
Melamine: In vivo and in vitro
unscheduled DNA synthesis (UDS) test:
None of the tested chemicals, including
melamine, were genotoxic
hepatocarcinogens in the in vivo assay,
and melamine was negative for UDS in
the in vitro assay.
Melamine: SOS/umu test: Negative for
its ability to result in DNA damage and
induce the expression of the umu operon.
Melamine: DNA synthesis-inhibition test
in Hela S3 cells: Inhibits DNA synthesis
by 50% at greater than 300 (iM.
Melamine: Sex-linked recessive
lethal/reciprocal translocation: Results
were considered equivocal based on
0.18% and 0.36% total lethal following
oral and injection exposure, respectively,
compared to control total lethal of 0.07%
for oral and 0.09% for injection.
Melamine: Drosophila Muller-5 test:
Negative for mutagenicity
Melamine: Drosophila melanogaster
Sex-linked recessive lethal: No mutagenic
effects were observed
Melamine: In vitro flow cytometric DNA
repair assay: Negative for genotoxic
effects
REFERENCE
Mastetal., 1982c
NTP, 1983a
NTP, 1983a
Mirsalis et al., 1983
Reifferscheid and Heil, 1996
Heil and Reifferscheid, 1992
NTP, 1983a
Rohrborn, 1959
Luers and Rohrborn, 1963
Seldonetal., 1994
DATA QUALITY
Limited study details reported.
Sufficient study details reported.
Sufficient study details reported.
Limited study details reported.
Nonguideline study.
Limited study details reported.
Sufficient study details reported.
Limited study details reported.
Limited study details reported.
Nonguideline study.
4-286
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Melamine: Microscreen assay: Positive
for genetic toxicity in E. coll WP2 cells
Rossman et al., 1991
Nonguideline study.
Melamine: Growth and genotoxic effects
to bacteria {Salmonella typhimurium) and
yeast (Saccharomyces cerevisiae): Non-
mutagenic in S. typhimurium with or
without S-9 mix. The growth of eight out
of nine strains tested was delayed by 10
mM melamine during 24 hour cultivation.
S. cerevisiae strain was tested, and did not
recover its growth following 48 hour
cultivation.
Ishiwata et al., 1991
Limited study details reported.
Proposed genotoxicity testing using a
metabolic activation system from bladder
epithelial cells (NTP, 1983) was never
conducted.
Lehner and Yokes, 2008;
Shigeru, 2007
Supporting information.
Reproductive Effects
HIGH: Estimated based on experimental data for melamine. A NOAEL of 10 mg/kg-day (LOAEL of 50
mg/kg-day) for increased apoptotic index of spermatogenic cells was reported in male mice orally
administered melamine for 5 days. In addition, altered epididymal sperm morphology and damage of
testicular DNA were reported at a dietary dose of 412 mg/kg-day (lowest dose tested). No experimental
data were located for melamine polyphosphate.
Reproduction/Developmental
Toxicity Screen
Rat, oral; potential for reproductive
toxicity
(Estimated by analogy)
Professional judgment
Estimated based on analogy to
confidential analog; LOAEL not
identified; study details not
provided.
Combined Repeated Dose with
Reproduction/ Developmental
Toxicity Screen
No data located.
Reproduction and Fertility Effects
Melamine: In a 5-day study, male mice
(8/group) were orally administered
melamine only at doses of 0, 2, 10 and 50
mg/kg-day or melamine in combination
with cyanuric acid at doses of 0, 1,5 and
25 mg/kg-day.
Sperm abnormalities were evaluated in a
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Yin etal., 2013
Adequate, primary study
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
separate select group of mice (8/group),
which were fed melamine only at doses of
0, 412, 824, and 1,648 mg/kg-day, or
melamine in combination with cyanuric
acid at doses of 0, 206, 412, or 824
mg/kg-day.
No deaths in mice fed 2, 10 and 50
mg/kg-day melamine or 1 and 5 mg/kg-
day melamine and cyanuric acid; 3 deaths
in co-administration group fed 25
mg/kg/day.
Grossly enlarged, pale yellow kidneys in
all mice that survived. Increase in
apoptotic index of spermatogenic cells in
mice fed 50 mg/kg-day melamine-only;
more severe apoptosis in co-administered
mice at 5 and 25 mg/kg-day.
NOAEL: 10 mg/kg-day
LOAEL: 50 mg/kg-day (increased
apoptotic index of spermatogenic cells)
Sperm abnormality group: no deaths in
mice administered melamine-only; all co-
administered mice died before day 6 and
exhibited anorexia, decreased activity and
hunched posture. Altered epididymal
sperm morphology (particularly the head
abnormality) and damage of testicular
DNA in all melamine-only treatment
groups.
NOAEL: Not established
LOAEL: 412 mg/kg-day (altered
epididymal sperm morphology; damage
of testicular DNA)
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Other
Developmental Effects
Reproduction/ Developmental
Toxicity Screen
Combined Repeated Dose with
Reproduction/ Developmental
Toxicity Screen
DATA
Melamine: There were no treatment-
related macroscopic or microscopic
effects on mammary glands, ovaries,
prostate, seminal vesicles, testes and
uterus in rats and mice up to dietary
concentrations of 18,000 ppm in a 13-
week study.
Melamine: Reproductive dysfunction
was observed at 0.5 mg/m3 and included
effects on spermatogenesis (genetic
material, sperm morphology, motility,
and count), effects on the embryo/fetus
(fetal death), pre -implantation mortality
(reduction in the number of implants per
female), and total number of implants per
corpora lutea.
REFERENCE
Melnick et al., 1984 (as cited in
OECD SIDS, 1999)
Ubaidullajev, 1993
DATA QUALITY
Limited study details reported in a
secondary source.
Study details, if present, were not
translated into English.
No data located.
MODERATE: Estimated based on a structural alert for aromatic amines. Limited experimental data for
melamine indicated no developmental effects in rats exposed during gestation to doses up to 1,060 mg/kg-
day. This experimental data is insufficient to determine a hazard designation for this endpoint.
There was no data located for the developmental neurotoxicity endpoint for this substance or its analogs.
No data located.
No data located.
4-289
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Prenatal Development
Postnatal Development
Prenatal and Postnatal
Development
Developmental Neurotoxicity
Other
Neurotoxicity
Neurotoxicity Screening Battery
DATA
Melamine: Signs of maternal toxicity at
136 mg/kg b.w. included decreased body
weight and feed consumption, hematuria
(23/25 rats), indrawn flanks (7/25 rats),
and piloerection (1/25 rats). No adverse
effects on gestational parameters and no
signs of developmental toxicity were
noted.
NOAEL > 1,060 mg/kg-day (highest
concentration tested);
LOAEL: Not established
Melamine: Only minor effects on the
fetuses or litters, including a non-
significant increase in resorptions in the
group treated on the 4th and 5th days of
gestation, were observed.
There was no data located for the
developmental neurotoxicity endpoint.
Potential for developmental toxicity
based on a structural alert for aromatic
amines.
(Estimated)
REFERENCE
Hellwig et al, 1996 (as cited in
OECD SIDS, 1999)
Thiersch, 1957
Professional judgment
DATA QUALITY
Sufficient study details reported.
Sufficient study details were not
available.
No data located.
No data located.
Estimated based on a structural alert
for aromatic amines and professional
judgment.
MODERATE: Estimated based on experimental data for melamine. Several neurological effects were
reported for different endpoints in 28-day studies evaluating mode of action in the brain. Impaired
memory abilities and cognition deficits were mediated by alterations of the pathways affecting the
hippocampus at a dose of 300 mg/kg-day (only dose tested). Design for the Environment (DfE) Alternatives
Assessment criteria values are tripled for chemicals evaluated in 28-day studies; the LOAEL of 300 mg/kg-
day falls on the threshold between Moderate and LOW hazard criteria. A NOAEL was not established and
it is assumed that effects would occur at a dose within the Moderate-High hazard criteria range; due to
this uncertainty, a Moderate hazard designation was assigned.
Melamine: In a 28-day study, male
Anetal. 2011
Sufficient study details reported in
4-290
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
(Adult)
Wistar rats (control group n = 8, treatment
group n = 10) were orally administered
tnelamine only at doses of 0, or 300
mg/kg-day.
A significant deficit of learning and
memory in a Morris water maze test was
•eported in the treated group. In addition
significantly lower field excitatory
postsynaptic potential (fEPSPs) slopes
were determined in a long term
potentiation (LTP) test from Schaffer
Collaterals to CA1 region in the
lippocampus in the treated group
ompared to the control group.
Authors concluded that melamine had a
;oxic effect on hippocampus resulting in
deficits of learning and memory in rats
associated with impairments of synaptic
plasticity.
NOAEL: Not established
GAEL: 300 mg/kg-day
primary source; only one dose tested.
Melamine: In a 28-day study, male
Wistar rats (10/group) were orally
administered melamine only at doses of 0,
or 300 mg/kg-day.
A significant deficit of learning and
memory in a Morris water maze test was
•eported in the treated group. In addition
significantly lower field excitatory
postsynaptic potential (fEPSPs) slopes
were determined in a long term
potentiation (LTP) test in the treated
group compared to the control group.
Decreased frequencies of spontaneous
EPSCs and minitura EPSCs were
observed in a long-time potentiation test,
4-291
Yang etal., 2011
Sufficient study details reported in
primary source; only one dose tested.
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
though there was no change in the
amplitude or kinetics of spontaneous or
initura EPSCs suggesting melamine's
[influence on glutamatergic transmission
ikely occurred presynaptic.
GAEL: Not established
LOAEL: 300 mg/kg-day
Melamine: In a 28-day study, male
Wistar rats (8/group) were orally
administered melamine only at doses of 0,
or 300 mg/kg-day.
A significant deficit of learning and
memory in a Morris water maze test was
reported in the treated group. Increased
evels of superoxide anion radical,
lydroxyl free radical and malonaldehyde
e reported. There was also decreased
superoxide dismutase and glutathione
seroxidase activity in the treated group
compared to the control. Hippocampal
energy metabolism analysis showed
ignificantly decreased adenosine-
riphosphate (ATP) content suggestive of
duced energy synthesis in the
ippocampal neurocytes possibly
associated with oxidative damage.
NOAEL = Not established
LOAEL = 300 mg/kg-day
Anetal, 2012
Sufficient study details reported in
primary source; only one dose tested.
Melamine: In a 28-day study, male
Wistar rats (8/group) were orally
administered melamine only at doses of 0,
or 300 mg/kg-day.
Anetal., 2013
Sufficient study details reported in
primary source; only one dose tested.
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
A significant deficit of learning and
memory in a Morris water maze test was
reported in the treated group. Increased
field excitatory postsynaptic potential
slopes was reported in the treated group.
There was decreased Ach levels and
increased AChE activity suggesting
damage to the function of cholinergic
system.
NOAEL = Not established
LOAEL = 300 mg/kg-day
Melamine: In a 28-day study, male
Wistar rats (8/group) were orally
administered melamine only at doses of 0,
or 300 mg/kg-day.
Impaired memory abilities were reported
in treated rats in the Morris water maze
ests compared to the control group.
Cognition deficits consistent with reduced
ong-term potentiation in the CA1 area of
he hippocampus were induced. Phase
ocking values showed reduced
synchronization between CA3 and CA1 in
theta and LG rhythms. Decreased
unidirectional indices for theta and LG
rhythms were reported in treated rats
suggesting that alterations of neural
information flow on CA3-CA1 pathway in
the hippocampus mediated cognitive
impairment in treated rats.
NOAEL = Not established
LOAEL = 300 mg/kg-day
4-293
Xuetal.,2013
Sufficient study details reported in
primary source; only one dose tested.
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Other
Potential for neurotoxicity is expected to
be low.
(Estimated)
Professional judgment
Estimated based on analogy and
professional judgment.
Repeated Dose Effects
MODERATE: Melamine polyphosphate is expected to be a moderate hazard for repeated dose effects
based on the data for melamine. Stones and diffuse epithelial hyperplasia in the urinary bladders were
observed in male rats at doses as low as 700 ppm (72 mg/kg-day; lowest dose tested). Exposure to
melamine has been associated with toxicity in humans.
Polyphosphoric Acid: Rat Repeated-
Dose Toxicity Study: An oral repeated-
dose toxicity test in rats resulted in a
TDLo of 450 mg/kg. The test substance
was identified as polyphosphates, and
was described as containing 1/3 Kurrol's
potassium salt and 2/3 pyrophosphate.
Toxic effects included changes in liver
weight, changes in tubules (including
acute renal failure, acute tubular
necrosis), and weight loss or decreased
weight gain.
Melamine: Rat 28-day dietary toxicity
study: Clinical signs included a dose-
related increase in pilo-erection, lethargy,
bloody urine spots in the cage and on the
pelage of animals, and
chromodacryorrhea. The incidence of
urinary bladder calculi and urinary
bladder hyperplasia in treated animals
was dose-dependent, with a significant
relationship between the calculi and
hyperplasia. Calculi composition
indicated the presence of an organic
matrix containing melamine, phosphorus,
sulfur, potassium, and chloride. Crystals
of dimelamine monophosphate were
identified in the urine.
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ARZNAD, 1957
RTI, 1983
Sufficient study details were not
available.
Sufficient study details reported.
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
NOAEL: estimated to be 2,000 ppm (240
mg/kg/day), excluding the observed
increase in water consumption and the
incidence of crystalluria.
LOAEL: 4,000 ppm (475 mg/kg/day)
based on the formation of calculi.
Melamine: Rabbit and dog 28-day
dietary toxicity study: No significant rise
in the body temperature of rabbits was
noted. Gross histological examination of
the heart, lung, liver, spleen, thyroid,
pancreas, intestines, kidneys and bladder
did not show pathological changes. A
zone of fat was found in the inner part of
the renal cortex in two dogs, but also in
the kidneys of 3 control dogs.
Lipschitz and Stokey, 1945
Sufficient study details were not
available.
Melamine: Rat 28-day dietary toxicity
study: Incidence and size of bladder
stones were directly related to the amount
of substance administered. The larger
stones were found to be unchanged
melamine in a matrix of protein, uric acid
and phosphate.
Lowest effective dose: 1,500 ppm (-125
mg/kg-day) in males
American Cyanamid Company,
1984
Sufficient study details were not
available.
Melamine: Rat 90-day dietary toxicity
study: one male rat receiving 18,000 ppm
and two males receiving 6,000 ppm died.
Mean body weight gain and feed
consumption were reduced. Stones and
diffuse epithelial hyperplasia in the
urinary bladders were observed in male
rats of all treatment groups. Focal
epithelial hyperplasia was observed in
NTP, 1983b;Melnicketal.
1984: ECHA, 201 la
Sufficient study details reported.
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
only 1 male. A second and third 13-week
repeated dose toxicity study was
conducted in rats at a dose range of 750 to
18,000 ppm; bladder stones were
observed at all dose levels.
LOAEL: 700 ppm (72 mg/kg/day)
Melamine: Mouse 90-day Dietary
Toxicity Study: A single female mouse
died after receiving 9,000 ppm. Mean
body weight gain relative to controls was
depressed. The incidence of mice with
bladder stones was dose-related and was
greater in males than in females. Sixty
percent of mice having bladder ulcers
also had urinary bladder stones. Bladder
ulcers were multifocal or associated with
inflammation (cystitis). Epithelial
hyperplasia and bladder stones were
observed together in 2 mice. Also,
epithelial cell atypia was seen.
NOAEL: 6,000 ppm (600 mg/kg-day)
LOAEL: 9,000 ppm (900 mg/kg-day)
NTP, 1983b;Melnicketal.
1984
Sufficient study details reported.
Melamine: Increased incidence of acute
and chronic inflammation and epithelial
hyperplasia of the urinary bladder was
observed in mice following oral (feed)
exposure for up to 103 weeks. There was
also increased incidence of bladder stones
in male mice.
LOAEL: 2,250 ppm (-380 mg/kg bw-
day; lowest dose tested)
NTP, 1983b;ECHA, 201 Ib
Repeated dose effects described in a
carcinogenicity bioassay study.
Melamine: Dog 1-year dietary toxicity
study: crystalluria started 60 to 90 days
into treatment, and persisted during the
study period. No other effects attributable
to melamine were observed.
American Cyanamid Company,
1955
Sufficient study details were not
available.
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Melamine: Rat 30-month dietary toxicity
study: neither accumulation of calculi nor
any treatment-related urinary bladder
lesions were found.
Mast et al., 1982a (as cited in
Wolkowski Tyl and Reel, 1992)
Sufficient study details were not
available.
Melamine: Rat 24- to 30-month dietary
toxicity study: a dose related trend for
dilated glands in glandular gastric mucosa
and inflammation in non glandular gastric
mucosa was observed. Urinary bladder
calculi formation was not observed.
American Cyanamid Company,
1983 (as cited in OECD SIDS,
1999)
Sufficient study details were not
available.
Melamine: Children affected by
melamine contaminated milk for
approximately 3 to 6 months before the
onset of kidney stones. The highest
content of melamine ranged from 0.090 to
619 mg/kg milk powder. A total of
52,857 children had received treatment
for melamine-tainted milk. 99.2% of the
children were younger than 3 yr. Some
children were asymptomatic; however
irritability, dysuria, difficulty in urination,
renal colic, hematuria, or stone passage,
hypertension, edema, or oliguria were
also reported. Mortality occurred in four
cases.
Hau et al., 2009
Summary of toxic effects from food
contamination.
Melamine: Renal damage is believed to
result from kidney stones formed from
melamine and uric acid or from melamine
and cyanuric acid. Cyanuric acid can be
produced in the gut by microbial
transformation of melamine. The bacteria
Klebsiella terrigena was shown to
convert melamine to cyanuric acid and
rats colonized by K. terrigena showed
exacerbated melamine-induced
nephrotoxicity.
Zheng etal, 2013
Supporting information about the
renal toxicity of melamine.
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Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Skin Sensitization
Skin Sensitization
Respiratory Sensitization
Respiratory Sensitization
Eye Irritation
Eye Irritation
Dermal Irritation
Dermal Irritation
DATA
REFERENCE
DATA QUALITY
LOW: Melamine polyphosphate is not expected to be a skin sensitizer based on the data for melamine.
Melamine: No evidence of primary
dermal irritation or Sensitization in a
human patch test
Melamine: Non-sensitizing to guinea
pigs
American Cyanamid Company,
1955; Trochimowicz et al., 2001
Fasset and Roudabush, 1963 (as
cited in OECD SIDS, 1999;
Trochimowicz et al., 2001)
Limited study details reported.
Limited study details reported.
No data located.
No data located.
LOW: Melamine polyphosphate is slightly irritating to eyes.
Melamine polyphosphate: Slightly
irritating
Melamine polyphosphate: Slightly
irritating
Melamine: Non-irritating to rabbit eyes
Melamine: Non-irritating to rabbit eyes
following 0.5 mL of 10% melamine
Melamine: Mild irritant to rabbit eyes
following exposure to 30 mg of dry
powder
Melamine: Slightly irritating to rabbit
eyes
NOTOX BV, 1998 (as cited in
Australia, 2006)
Submitted confidential study
BASF, 1969 (as cited in OECD
SIDS, 1999; IUCLID, 2000a)
American Cyanamid Company,
1955; Trochimowicz et al., 2001
American Cyanamid Company,
1955; Trochimowicz et al., 2001
Marhold, 1972 (as cited in
IUCLID, 2000a; RTECS, 2009)
Limited study details reported.
Limited study details reported.
Limited study details reported.
Limited study details reported.
Limited study details reported.
Limited study details reported.
VERY LOW: Melamine polyphosphate is not a skin irritant.
Melamine polyphosphate: Not irritating
Melamine polyphosphate: Not irritating
Melamine: Not irritating to rabbit skin
Melamine: Not irritating to rabbit skin
NOTOX BV, 1998 (as cited in
Australia, 2006)
Submitted confidential study
Rijcken, 1995 (as cited in OECD
SIDS, 1999)
BASF, 1969 (as cited in OECD
SIDS, 1999; IUCLID, 2000a)
Limited study details reported.
Limited study details reported.
Organisation for Economic
Cooperation and Development
(OECD) 404 guideline study.
Limited study details reported.
4-298
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Endocrine Activity
Immunotoxicity
Immune System Effects
DATA
Melamine: Not irritating to rabbit skin
Melamine: Not irritating to rabbit skin
REFERENCE
American Cyanamid Company,
1955; Trochimowicz et al., 2001
Fasset and Roudabush, 1963 (as
cited in OECD SIDS, 1999;
Trochimowicz et al., 2001)
DATA QUALITY
Limited study details reported.
Limited study details reported.
There were insufficient data located to describe the effect of melamine polyphosphate on the endocrine
system. In one study, melamine did not exhibit estrogenic activity in vitro in a yeast two-hybrid assay.
Melamine: Showed no estrogenic
activity (no change in B-galactosidase
activity) in an in vitro yeast two-hybrid
assay in Saccharomyces cerevisiae Y 190
ECHA,2011b
Reported in a secondary source.
Nonguideline study.
Potential for immunotoxic effects based on analogy to structurally similar polymers and professional
judgment.
Potential for immunotoxicity
Melamine: Did not inhibit the
mitogenesis of B- and T- lymphocytes in
an in vitro mouse lymphocyte
mitogenesis test.
Professional judgment
ECHA,2011a
Estimated based on confidential
analogs and professional judgment.
Data from a secondary source.
ECOTOXICITY
ECOSAR Class
Acute Aquatic Toxicity
Fish LC50
Melamine s
LOW: Melamine polyphosphate is expected to be of low hazard for acute toxicity to aquatic organisms
based on experimental data for melamine polyphosphate and experimental data for melamine. For
melamine, the weight of evidence suggests that the acute values are >100 mg/L. For melamine
polyphosphate, no effects were observed in algae at the highest concentration tested (3.0 mg/L). Melamine
polyphosphate is not predicted to cause eutrophication based on laboratory testing.
Melamine polyphosphate: Freshwater
fish 96-hour LC50 = 100 mg/L
(Experimental)
Melamine: Leuciscus idus melanotus 48-
hour LC50 >500 mg/L
(Experimental)
Melamine: Oryzias latipes 48-hour LC50
Ciba, 2005 (as cited in Australia,
2006)
OECD SIDS, 1999
OECD SIDS, 1999
Reported in a secondary source,
study details and test conditions
were not reported.
Study details reported in secondary
source.
Study details reported in secondary
4-299
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Daphnid LC50
DATA
= 1,000 mg/L
(Experimental)
Melamine: Poecilia reticulata 96-hour
LC50 >3,000 mg/L
(Experimental)
Melamine: Poecilia reticulata 4,400
mg/L dose lethal to <10%
(Experimental)
Melamine: Fish 96-hour LC50 = >100
mg/L
(Estimated)
ECOSAR: Anilines (amino-meta)
Melamine: Fish 96-hour LC50 = >100
mg/L
(Estimated)
ECOSAR: Melamines
Melamine polyphosphate: Daphnia
magna 48-hour EC50 >100 mg/L
(Experimental)
Melamine: Daphnia magna 48-hour
LC50 >2,000 mg/L
(Experimental)
Melamine: Daphnid 48-hour LC50 = 6.23
mg/L
(Estimated)
ECOSAR: Anilines (amino-meta)
Melamine: Daphnid 48-hour LC50 =
>100 mg/L
ECOSAR: Melamines
(Estimated)
REFERENCE
OECD SIDS, 1999
OECD SIDS, 1999
ECOSAR v 1.11
ECOSAR v 1.11
Ciba, 2005 (as cited in Australia,
2006)
OECD SIDS, 1999
ECOSAR v 1.11
ECOSAR v 1.11
DATA QUALITY
source.
Study details reported in secondary
source.
Study details reported in secondary
source.
ECOSAR provided results for the
Anilines (amino-meta) class;
however, professional judgment
indicates that this compound does
not lie within the domain of the
ECOSAR model.
Reported in a secondary source,
study details and test conditions
were not reported.
Study details reported in secondary
source.
ECOSAR provided results for the
Anilines (amino-meta) class;
however, professional judgment
indicates that this compound does
not lie within the domain of the
ECOSAR model.
4-300
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Green Algae EC50
Chronic Aquatic Toxicity
Fish ChV
DATA
Melamine polyphosphate: In a 96-hour
control growth test (Selenastrum
capricornutum), melamine polyphosphate
causes increased algal growth, but growth
is 95% less than growth in standard
medium with adequate phosphorous. This
indicates that melamine polyphosphate is
not a good source of phosphorous for
algal growth and does not cause
eutrophication.
(Experimental)
Melamine: Scenedesmus pannonicus 4-
day EC50 = 940 mg/L; 4-day NOEC =
320 mg/L
(Experimental)
Melamine: Green algae 96-hour EC50 =
2.79 mg/L
(Estimated)
ECOSAR: Anilines (amino-meta)
Melamine: Green algae 96-hour EC50 =
>100 mg/L
(Estimated)
ECOSAR: Melamines
REFERENCE
Submitted confidential study
OECD SIDS, 1999
ECOSAR v 1.11
ECOSAR v 1.11
DATA QUALITY
Sufficient study details reported in a
confidential study.
Reported in a secondary source,
study details and test conditions
were not provided.
ECOSAR provided results for the
Anilines (amino-meta) class;
however, professional judgment
indicates that this compound does
not lie within the domain of the
ECOSAR model.
LOW: Melamine polyphosphate is expected to be of low hazard for chronic toxicity to aquatic organisms
based on experimental data for melamine. For melamine, the weight of evidence suggests that the chronic
values are >10 mg/L. For melamine polyphosphate, no effects were observed in algae at the highest
concentration tested (3.0 mg/L).
Melamine: Jordanella floridae 35-day
NOEC> 1,000 mg/L
(Experimental)
Melamine: Salmo gairdneri NOEC
(macroscopic) = 500 mg/L; NOEC
(microscopic) <125 mg/L
OECD SIDS, 1999
OECD SIDS, 1999
Reported in a secondary source,
study details and test conditions
were not provided.
Reported in a secondary source,
study details and test conditions
were not provided.
4-301
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Daphnid ChV
Green Algae ChV
DATA
(Experimental)
Melamine: Fish ChV = >100 mg/L
(Estimated)
ECOSAR: Anilines (amino-meta)
Melamine: Fish ChV = >100 mg/L
(Estimated)
ECOSAR: Melamines
Melamine: Daphnia magna 21 -day LC50
= 32-56 mg/L, 21-day LCioo = 56 mg/L,
21-dayNOEC= 18 mg/L
(Experimental)
Melamine: Daphnid ChV = 0.078 mg/L
(Estimated)
ECOSAR: Anilines (amino-meta)
Melamine: Daphnid ChV = 14.85 mg/L
(Estimated)
ECOSAR: Melamines
Melamine polyphosphate: Selenastrum
capricornutum 96-hour EC50 >3.0 mg/L;
96-hour NOEC = 3.0 mg/L
(Experimental)
Melamine polyphosphate: Selenastrum
capricornutum 96-hour EC50 >3.0 mg/L;
96-hour NOEC = 3.0 mg/L
(Experimental)
REFERENCE
ECOSAR v 1.11
ECOSAR v 1.11
OECD SIDS, 1999
ECOSAR v 1.11
ECOSAR v 1.11
Submitted confidential study
Australia, 2006
DATA QUALITY
ECOSAR provided results for the
Anilines (amino-meta) class;
however, professional judgment
indicates that this compound does
not lie within the domain of the
ECOSAR model.
Reported in a secondary source,
study details and test conditions
were not provided.
ECOSAR provided results for the
Anilines (amino-meta) class;
however, professional judgment
indicates that this compound does
not lie within the domain of the
ECOSAR model.
No effects observed at highest
concentration tested.
Reported in a secondary source,
study details and test conditions
were not provided; no effects
observed at highest concentration
tested.
4-302
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
Melamine: Green algae ChV = 0.70
mg/L
(Estimated)
ECOSAR: Anilines (amino-meta)
Melamine: Green algae ChV = 81.26
mg/L
(Estimated)
ECOSAR: Melamines
REFERENCE
ECOSAR v 1.11
ECOSAR v 1.11
DATA QUALITY
ECOSAR provided results for the
Anilines (amino-meta) class;
however, professional judgment
indicates that this compound does
not lie within the domain of the
ECOSAR model.
ENVIRONMENTAL FATE
Transport
Henry's Law Constant (atm-
m3/mole)
Sediment/Soil
Adsorption/Desorption - Koc
Level III Fugacity Model
Melamine polyphosphate has a high measured water solubility of 20 g/L and its Henry's Law constant and
vapor pressure are below cutoff values. It is expected to partition predominately to water and soil. It may
migrate from soil into groundwater. As a salt, volatilization from either wet or dry surfaces is not expected
to be an important fate process.
<10'8 (Estimated)
Melamine polyphosphate: 13
(Estimated)
Air = 0%
Water = 37%
Soil = 63%
Sediment = 0% (Estimated)
for Melamine Polyphosphate
EPIv4. 10; Professional
judgment
EPIv4.10
EPIv4.10
Cutoff value for nonvolatile
compounds.
4-303
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Persistence
HIGH: Melamine polyphosphate is expected to show high persistence in the environment based on the
data for melamine. Melamine polyphosphate is expected to be fully dissociated under environmental
conditions. The weight of evidence suggests that melamine will biodegrade at rates consistent with a High
hazard designation. Although pure culture studies showed evidence of biodegradation by enzymatic
hydrolytic deamination in less than 10 days, an original MITI test detected less than 30% degradation
after 14 days and two separate guideline OECD 302B studies observed no degradation after 28 days and
16% degradation after 20 days. This results in an expected environmental persistence half-life between 60
and 180 days. Degradation of melamine or its cation by hydrolysis or direct photolysis is not expected to be
significant as the functional groups present on this molecule do not tend to undergo these reactions under
environmental conditions. Polyphosphoric acid is expected to have low persistence in the environment. The
weight of evidence suggests that polyphosphoric acid will hydrolyze under environmental conditions. The
phosphates formed are expected to participate in natural cycles and be readily assimilated.
Water
Aerobic Biodegradation
Melamine polyphosphate:
Weeks (Primary survey model)
Months (Ultimate survey model)
(Estimated)
Melamine: 16% removal after 20 days
with activated sludge, 14% removal after
10 days with adapted sludge (Measured)
Melamine: 0% removal after 28 days
with activated sludge (Measured)
Melamine: 0% removal after 14 days
with activated sludge (Measured)
Melamine: <30% removal after 14 days
with activated sludge (Measured)
Melamine: <1% removal after 5 days
with an adapted inoculum (Measured)
4-304
EPIv4.10
OECD SIDS, 1999
OECD SIDS, 1999
OECD SIDS, 1999
OECD SIDS, 1999
IUCLID, 2000a
These values are for the dissociated
component, melamine. Reported in a
secondary source, study details and
test conditions were not provided.
These values are for the dissociated
component, melamine. Reported in a
secondary source, study details and
test conditions were not provided.
These values are for the dissociated
component, melamine. Reported in a
secondary source, study details and
test conditions were not provided.
These values are for the dissociated
component, melamine. Reported in a
secondary source, study details and
test conditions were not provided.
These values are for the dissociated
component, melamine. Reported in a
secondary source, study details and
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Melamine: 0% removal after 14 days
with activated sludge (Measured)
IUCLID, 2000a
Melamine: <30% removal after 14 days
with activated sludge (Measured)
IUCLID, 2000a
Melamine: <20% removal after 20 days,
14% removal after 10 days with adapted
inoculum (Measured)
IUCLID, 2000a
Study results: 100%/<10 days
Test method: Pure culture study
Melamine: Bacterium, Nocardioides sp.
Strain ATD6 rapidly degraded melamine
and accumulated cyanuric acid and
ammonium ion, via the intermediates
ammeline and ammelide. (Measured)
Takagietal., 2012
test conditions were not provided.
These values are for the dissociated
component, melamine. Reported in a
secondary source, study details and
test conditions were not provided.
These values are for the dissociated
component, melamine. Reported in a
secondary source, study details and
test conditions were not provided.
These values are for the dissociated
component, melamine. Reported in a
secondary source, study details and
test conditions were not provided.
Melamine degradation was found to
occur in species specific
biodegradation studies.
Volatilization Half-life for Model
River
>1 year for Melamine polyphosphate
(Estimated)
EPIv4.10
Based on the magnitude of the
estimated Henry's Law constant.
Volatilization Half-life for Model
Lake
>1 year for Melamine polyphosphate
(Estimated)
EPIv4.10
Based on the magnitude of the
estimated Henry's Law constant.
Soil
Aerobic Biodegradation
Study results: 0%/28 days
Test method: 302B: Inherent - Zahn-
Wellens/EMPA Test
Melamine: Not readily biodegradable:
0% biodegradation detected after 2 weeks
with 100 ppm in 30 ppm activated sludge
(OECD TG 301C) (Measured); 0%
degradation after 28 days with 100 mg
DOC/L in activated sludge (Zahn-
Wellens test, OECD 302B) (Measured)
4-305
MITI, 1998; OECD SIDS, 1999
Adequate values from guideline
studies for the dissociated
component, melamine.
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Air
Reactivity
Anaerobic Biodegradation
Soil Biodegradation with Product
Identification
Sediment/Water Biodegradation
Atmospheric Half-life
Photolysis
Hydrolysis
DATA
Study results: 100%/4days
Test method: Pure culture study
Melamine: Bacterium, A. citntlli strain
B-12227 rapidly degraded melamine and
accumulated cyanuric acid, ammeline and
ammelide, via the intermediates
ammeline and ammelide. (Measured)
Melamine: A set of soil bacteria has been
identified whose members rapidly
metabolize melamine as their source of
nitrogen to support growth; these bacteria
contain an enzyme which hydrolytically
deaminates melamine. (Measured)
Study results: <8.9%/28 days
Test method: Other
Melamine: 0-8. 9% nitrification was
observed after 28 days incubation with
bacteria in Webster silty clay loam under
anaerobic conditions. (Measured)
Melamine: Nitrification of melamine
occurs in soil at a low rate (0.7% organic
N found as NO3-N in week 10, and 0 %
in week 28). (Measured)
Melamine polyphosphate: 21 days
(Estimated)
Melamine polyphosphate: Not a
significant fate process (Estimated)
Polyphosphoric acid: The half-life for
the hydrolysis to phosphoric acid is
several days at 25 °C (Measured)
REFERENCE
Shiomi and Ako, 2012
Cook and Hutter, 1981; Cook
andHutter, 1984
IUCLID, 2000a
ECHA, 20 1 Ib; ECHA, 20 1 la
EPIv4.10
Professional judgment; Mill,
2000
Gard, 2005
DATA QUALITY
Melamine degradation was found to
occur in species specific
biodegradation studies.
Melamine degradation was found to
occur in species specific
biodegradation studies.
This value is for the dissociated
component, melamine. Reported in a
secondary source, study details and
test conditions were not provided.
Non guideline studies for the
dissociated component, melamine.
No data located.
The substance does not contain
functional groups that would be
expected to absorb light at
environmentally significant
wavelengths.
This value is for the dissociated
component, polyphosphoric acid.
These studies indicate
polyphosphoric acid would undergo
4-306
-------
Melamine Polyphosphate CASRN 15541-60-3
PROPERTY/ENDPOINT
Environmental Half-life
Bioaccumulation
Fish BCF
Other BCF
BAF
Metabolism in Fish
DATA
Polyphosphoric acid: Hydrolysis occurs
in 2 months at 20°C (Measured)
Melamine polyphosphate: 120 days
(Estimated)
REFERENCE
IUCLID, 2000b
PBT Profiler vl.301
DATA QUALITY
hydrolysis under environmental
conditions to phosphate ions.
Reported in a secondary source,
study details and test conditions
were not provided.
This value is for the dissociated
component, polyphosphoric acid.
Reported in a secondary source,
study details and test conditions
were not provided available.
Half-life estimated for the
predominant compartment, as
determined by EPI and the PBT
Profiler methodology.
LOW: Based on the relatively high water solubility of melamine polyphosphate (20 g/L) and an estimated
BCF of 3.2. In addition, the experimental bioconcentration values for the melamine component are low,
BCF <3.8, and BAF <1.
Melamine polyphosphate: 3.2
(Estimated)
Melamine: <0.38 in carp (Cyprinus
carpio) after 6 weeks at 2.0 ppm
concentration;
<3.8 in carp (Cyprinus carpio) after 6
weeks at 0.2 ppm concentration (OECD
302B) (Measured)
Melamine polyphosphate: 0.9
(Estimated)
Melamine: 0.9 (Estimated)
Melamine: Uptake, bioaccumulation and
elimination study with 14C-melamine in
fathead minnow and rainbow trout: BCFs
<1 (Measured)
EPIv4.10
MITI, 1998
EPIv4.10
EPIv4.10
ECHA, 20 1 Ib; ECHA, 20 1 la
Adequate values from guideline
studies for the dissociated
component, melamine.
No data located.
Non guideline studies that support
the low potential for
bioaccumulation of this substance.
ENVIRONMENTAL MONITORING AND BIOMONITORING
4-307
-------
Melamine Polyphosphate CASRN
PROPERTY/ENDPOINT
Environmental Monitoring
Ecological Biomonitoring
Human Biomonitoring
DATA
No data located.
15541-60-3
REFERENCE
DATA QUALITY
No data located.
This chemical was not included in the NHANES biomonitoring report (CDC, 201 1).
4-308
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ARZNAD (1957) The physiologic action of polyphosphate. Arzneimittel-Forschung Drug Research. Arzneimittelforschung 7:172-175.
American Cyanamid Company (1955) Melamine: Acute and chronic toxicity Report 55-21 Unpublished study.
American Cyanamid Company (1983) 2-Year chronic feeding study of melamine in Fischer 344 rats. Hazelton Raltech Report for American
Cyanamid Company.
American Cyanamid Company (1984) Summary of company study.
Anonymous (1958) AERO Melamine, In-House publication. Wayne, NJ: American Cyanamid Company.
Australia (2006) Melapur 200 and Polymer in Exolit OP 1312. Australia. National Industrial Chemicals Notification and Assessment Scheme.
http://www.nicnas.gov.au/publications/CAR/new/Ltd/LtdFULLR/ltdlOOOFR/ltdl282FR.pdf.
BASF (1969) BASF AG, Department of Toxicology (XIX5), unpublished data (As cited in Melamine OECD SIDS document and melamine
IUCLID document).
Baynes RE, Smith G, Mason SE, et al. (2008) Pharmacokinetics of melamine in pigs following intravenous administration. Food Chem Toxicol
46:1196-1200.
Boethling RS and Nabholz JV (1997) Environmental assessment of polymers under the U.S. Toxic Substances Control Act. Washington, DC: U.S.
Environmental Protection Agency.
CDC (2011) Fourth national report on human exposure to environmental chemicals, updated tables, February 2011. Centers for Disease Control
and Prevention, Department of Health and Human Services, http://www.cdc.gov/exposurereport/.
Chu CY, Chu KO, Chan JY, et al. (2010) Distribution of melamine in rat foetuses and neonates. Toxicol Lett 199(3):398-402.
Ciba (2005) Acute oral toxicity study in rats; Test Report Number A 18685 (unpublished report). Fullinsdorf, Switzerland: Ciba Specialty
Chemicals, Inc.
Cook AM and Hutter R (1984) Deethylsimazine: Bacterial dechlorination, deamination, and complete degradation. J Agric Food Chem 32:581-
585.
Cook Am and Hutter R (1981) s-Triazines as nitrogen sources for bacteria. J Agric Food Chem 29:1135-1143.
Crews GM, Ripperger W, Kersebohm DB, et al. (2006) Melamine and guanamines. Ullmann's encyclopedia of industrial chemistry.22 John Wiley
& Sons, Inc.
4-309
-------
ECHA (201 la) Melamine cyanurate. Registered substances. European Chemicals Agency.
http://apps.echa.europa.eu/registered/data/dossiers/DISS-9eb230bf-9edO-1955-e044-00144f67d031/AGGR-a3a77856-6622-456f-8995-
5483f815f4a4_DISS-9eb230bf-9edO-1955-e044-00144f67d031.html.
ECHA (20lib) Melamine. Registered Substances Database. European Chemicals Agency.
http://apps.echa.europa.eu/registered/data/dossiers/DISS-9c8039ea-8496-674c-e044-00144f67d249/DISS-9c8039ea-8496-674c-e044-
00144f67d249_DISS-9c8039ea-8496-674c-e044-00144f67d249.html.
ECHA (2013) Melamine. Registered substances. European Chemicals Agency. http://apps.echa.europa.eu/registered/data/dossiers/DISS-
9c8039ea-8496-674c-e044-00144f67d249/AGGR-2f9a90f3-6e35-4292-937a-99dOf4cf998a_DISS-9c8039ea-8496-674c-e044-
00144f67d249.html#AGGR-2f9a90f3-6e35-4292-937a-99dOf4cf998a.
ECHA (2014) Polyphosphoric acids. http://apps.echa.europa.eu/registered/data/dossiers/DISS-dffb4072-e49b-47ae-e044-00144f67d031/AGGR-
d3ff4c4f-4322-4d5e-a658-c8162ebf3867_DISS-dffb4072-e49b-47ae-e044-00144f67d031.html#AGGR-d3ff4c4f-4322-4d5e-a658-c8162ebf386.
ECOSAR Ecological Structure Activity Relationship (ECOSAR). Estimation Programs Interface (EPI) Suite for Windows, Version 1.11.
Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency, http://www.epa.gov/oppt/newchems/tools/21ecosar.htm.
EPA (2012) Using noncancer screening within the SF initiative. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/sf/pubs/noncan-screen.htm.
EPI Estimation Programs Interface (EPI) Suite, Version 4.10. Washington, DC: EPIWIN/EPISUITE. U.S. Environmental Protection Agency.
http://www.epa.gov/opptintr/exposure/pubs/episuitedl.htm.
Fasset DW and Roudabush RL (1963) Unpublished data (referenced by melamine OECD SIDS document and Tropchimowicz, 2001). Lab. of Ind.
Med., Eastman Kodak Co.
Galloway SM, Armstrong MJ, Reuben C, et al. (1987) Chromosome Aberrations And Sister Chromatid Exchanges in Chinese Hamster Ovary
Cells: Evaluations of 108 Chemicals. Environ Mol Mutagen 10(Suppl 10): 1-175.
Gard DR (2005) Phosphoric acids and phosphates. Kirk-Othmer encyclopedia of chemical technology. Wiley-Interscience.
http://onlinelibrary.wiley.com/book/10.1002/0471238961.
HSDB (2008) Melamine. Hazardous Substances Data Bank. National Library of Medicine. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen7HSDB.
Hau AK, Kwan TH, Li PK (2009) Melamine toxicity and the kidney. 20(2):245-250.
Haworth S, Lawlor T, Mortelmans K, et al. (1983) Salmonella mutagenicity test results for 250 chemicals. Environ Mutagen 1:3-142.
4-310
-------
Heil J and Reifferscheid G (1992) Detection of mammalian carcinogens with an immunological DNA synthesis-inhibition test. Carcinogenesis
13(12):2389-2394.
Hellwig J, Gembrandt C, Hildebrandt B (1996) Melamine - Prenatal toxicity in Wistar rats after oral administration (diet) Project Number
32R0242/94007.
Hoechst AG (1963) (Cited in melamine IUCLID document). Unveroffentl Unters Bericht 5(7)
Huff JE (1984) Carcinogenesis results on seven amines, two phenols, and one diisocyanate used in plastics and synthetic elastomers. Industrial
hazardous plastics and synthetic elastomers.
IARC (1999) Melamine. IARC Monogr Eval Carcinog Risk Chem Hum 73 International Agency for Research on Cancer World Health
Organization.: 329-33 8.
IUCLID (2000a) Dataset for Melamine. European Commission, European Chemicals Bureau.
IUCLID (2000b) Dataset for Polyphosphoric Acids. European Commission, European Chemicals Bureau.
IshiwataH, SugitaT, Kozaki M, et al. (1991) Inhibitory effects of melamine on the growth and physiological activities of some microorganisms.
32(5):408-413.
Lehner T and Yokes K (2008) Personal Communication by email between Kathleen Yokes and Theo Lehner, January 22, 2008.
Lipschitz WL and Stokey E (1945) The mode of action of three new diuretics: melamine, adenine and formoguanamine. J Pharmacol Exp Ther
83:235-249.
Liu G, Li S, Jia J, et al. (2010) Pharmacokinetic study of melamine in rhesus monkey after a single oral administration of atolerable daily intake
dose. Regul Toxicol Pharmacol 56(2): 193-196.
Luers H and Rohrborn G (1963) The mutagenic activity of ethylenimine derivatives with different numbers of reactive groups. Proceedings of the
llth International Congress. 1:64-65.
Lusby AF, Simmons Z, McGuire PM (1979) Variation in mutagenicity of s-Triazine compounds tested on four salmonella strains. Environ
Mutagen 1:287-290.
MITI (1998) Biodegradation and bioaccumulation data of existing chemicals based on the CSCL Japan. Japan: Ministry of International Trade &
Industry. Chemicals Inspection & Testing Institute. Japan Chemical Industry Ecology-Toxicology & Information Center.
4-311
-------
Marhold JV (1972) [Sbornik vysledku toxixologickeho vysetreni latek apripravku].: 153.
Mast RW, Boyson BG, Giesler PJ (1982a) Evaluation of the chronic toxicity of melamine in a 30-month Fischer 344 rat feeding study.
Toxicologist
Mast RW, Friedman MA, Finch RA (1982b) Mutagenicity testing of melamine. Toxicologist 2:172.
Mast RW, Jeffcoat AR, Sadler BM, et al. (1983) Metabolism, disposition and excretion of [14C]melamine in male Fischer 344 rats. Food Chem
Toxicol21(6):807-810.
Mast RW, Naismith RW, Friedman MA (1982c) Mouse micronucleus assay of melamine. Environ Mutagen 4:340-341.
Matsui-Yuasa I, Otani S, Yano Y, et al. (1992) Spermidine/spermine Nl-acetyltransferase, a new biochemical marker for epithelial proliferation in
rat bladder. Jpn J Cancer Res 83:1037-1040.
May DR (1979) Cyanamids. Kirk-Othmer encyclopedia of chemical technology.7 New York: John Wiley & Sons.:291-306.
McGregor DB, Brown A, Cattanach P, et al. (1988) Responses of the L5178Y tk+/tk- mouse lymphoma cell forward mutation assay: III. 72 coded
chemicals. Environ Mol Mutagen 12:85-154.
Melnick RL, Boorman GA, Haseman JK, et al. (1984) Urolithiasis and bladder carcinogenicity of melamine in rodents. Toxicol Appl Pharmacol
72(2):292-303.
Mill T (2000) Photoreactions in surface waters. In: Boethling R, Mackay D, eds. Handbook of Property Estimation Methods for Chemicals,
Environmental Health Sciences. Boca Raton: Lewis Publishers.:355-381.
Mirsalis J, Tyson K, Beck J, et al. (1983) Induction of unscheduled DNA synthesis (UDS) in hepatocytes following in vitro and in vivo treatment.
Environ Mutagen 5(482):344.
NOTOX B.V. (1998) Screening tests for primary skin and eye irritation in the rabbit and acute oral toxicity in the rat; Test Report Number 221941
and 221952 (unpublished report). Hertogenbosch, The Netherlands: DSM Melapur.
NTP (1983a) Carcinogenesis bioassay of melamine (CAS No. 108-78-1) in F344/N rats and B6C3F1 mice (feed study). National Cancer Institute.
National Toxicology Program. http://ntp.niehs.nih.gov/ntp/htdocs/LT_rpts/tr245.pdf.
NTP (1983b) NTP Carcinogenesis Bioassay of Melamine (CAS No. 108-78-1) in F344/N Rats and B6C3F1 Mice (Feed Study). Natl Toxicol
Program Tech Rep Ser 245:1 -171.
4-312
-------
New Line Safety (2011) Ceasefire AC-2 Material Safety Data Sheet. New Line Safety, LLC.
OECD SIDS (1998) Screening information data set - SIDS - for high production volume chemicals - Volume 7, Parts 1, 2 and 3- Melamine.
356(1) Organisation for Economic Cooperation and Development. Screening Information Data Set.:3.
OECD SIDS (1999) Full SIDS dossier on the HPV phase 2 chemical melamine. Organisation for Economic Cooperation and Development.
Screening Information Data Set. http://www.chem.unep.ch/irptc/sids/OECDSIDS/108781.pdf
Ogasawara H, Imaida K, Ishiwata H, et al. (1995) Urinary bladder carcinogenesis induced by melamine in F344 male rats: correlation between
carcinogenicity and urolith formation. Carcinogenesis 16(11):2773-2777.
Okumura M, Hasegawa R, Shirai T, et al. (1992) Relationship between calculus formation and carcinogenesis in the urinary bladder of rats
administered the non-genotoxic agents, thymine or melamine. Carcinogenesis 13(6): 1043-1045.
OncoLogic (2008) Version 7.0. U.S. Environmental Protection Agency and LogiChem, Inc.
PBT Profiler Persistent (P), Bioaccumulative (B), and Toxic (T) Chemical (PBT) Profiler, Version 1.301. Washington, DC: U.S. Environmental
Protection Agency, www.pbtprofiler.net.
Pakalin S, Cole T, Steinkeliner J, et al. (2007) Review on production processes of decabromodiphenyl ether (DECABDE) used in polymeric
applications in electrical and electronic equipment, and assessment of the availability of potential alternatives to DECABDE. European Chemicals
Bureau, European Commission, http://publications.jrc.ec.europa.eu/repository/bitstream/l 1111111 l/5259/l/EUR%2022693.pdf
Partanen H, Vahakangas K, Woo CS, et al. (2012) Transplacental transfer of melamine. Placenta 33(l):60-66.
Perrella FW and Boutwell RK (1983) Triethylenemelamine: An initiator of two-stage carcinogenesis in mouse skin which lacks the potential of a
complete carcinogen. Cancer Lett 21(1):37-41.
RTECS (2009) Melamine. Registry of Toxic Effects of Chemical Substances.
RTI (1983) Evaluation of Urolithiasis Induction by Melamine (CAS No. 108-78-1) in Male Weanling Fischer 344 Rats. Parts I and II: In-Life
Observations, Necropsy, and Histopathology of Urinary Bladders and Analysis of Plasma, Urine and Calculi. Research Triangle Institute.
Reifferscheid G and Heil J (1996) Validation of the SOS/umu test using test results of 486 chemicals and comparison with the Ames test and
carcinogenicity data. Mutat Res 369:129-145.
Rijcken WRP (1995) Primary skin irritation/corrosion study with melamine in the rabbit Confidential NOTOX project 146205 for DSM melamine.
4-313
-------
Rohrborn G (1959) Mutation tests with melamine and trimethylolmelamine. 33:156.
Rossman TG, Molina M, Meyer L, et al. (1991) Performance of 133 compounds in the lambda prophage induction endpoint of the microscreen
assay and a comparison with S. typhimurium mutagenicity and rodent carcinogenicity assays. Mutat Res 260:349-367.
Rutty CJ and Abel G (1980) In vitro cytotoxicity of the methylmelamines. Chem Biol Interact 29(2):235-246.
Rutty CJ and Connors TA (1977) In vitro studies with hexamethylmelamine. Biochem Pharmacol 26(24):2385-2391.
Seiler JP (1973) A survey on the mutagenicity of various pesticides. Experientia 29:622-623.
Seldon JR, Dolbeare F, Clair JH, et al. (1994) Validation of a flow cytometric in vitro DNA repair (UDS) assay in rat hepatocytes. 315(2): 147-
167.
Shelby MD, Erexson GL, Hook GJ, et al. (1993) Evaluation of a three-exposure mouse bone marrow micronucleus protocol: Results with 49
chemicals. Environ Mol Mutagen 21:160-179.
Shigeru M (2007) Personal Communication. Chemtura. October, 2007.
Shiomi N and Ako M (2012) Biodegradation of melamine and cyanuric acid by a newly-isolated microbacterium strain. 2:303-309.
Takagi K, Fujii K, Yamazaki K, et al. (2012) Biodegradation of melamine and its hydroxyl derivatives by a bacterial consortium containing a
novel Nocardioides species. Appl Microbiol Biotechnol 94:1647-1656.
Thiersch JB (1957) Effect of 2,4,6, Triamino-"S"-Triazine (TR), 2,4,6 "Tris" (Ethyleneimino)-"S"Triazine (TEM) and N, N', N"-
Triethylenephosphoramide (TEPA) on Rat Litter in Utero. Proc Soc Exp Biol Med 94:36-40.
Trochimowicz HJ, Kennedy GL, Krivanek ND (2001) Alkylpyridines and miscellaneous organic nitrogen compounds. Patty's toxicology.
Ubaidullajev RU (1993) (In Russian). Gig Sanit 58:14-16.
Unknown (1990) Acute toxicity data. J Am Coll Toxicol 1:100.
Weber JB (1970) Mechanisms of absorption of s-triazines by clay colloids and factors affecting plant availability. 32:93-130.
Wolkowski Tyl R and Reel JR (1992) Evaluation of urolithiasis induction by melamine [CAS 108-78-1] in male weanling Fischer 344 rats. Part I:
in-life observations, necropsy and histopathology of urinary bladders. Part I: addenda. Part II: analysis of plasma, urine and calculi. Submitted to
the U.S. Environmental Protection Agency under TSCA section 8E.
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Yin RH, Wang XZ, Bai WL, et al. (2013) The reproductive toxicity of melamine in the absence and presence of cyanuric acid in male mice. Res
VetSci94(3):618-627.
Zheng X, Zhao A, et al (2013) Melamine-induced renal toxicity is mediated by the gut microbiota. Sci Transl Med 5(172): 122.
4-315
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Silicon Dioxide (amorphous)
VL = Very Low hazard L = Low hazard = Moderate hazard H = High hazard VH = Very High hazard — Endpoints in colored text (VL, L, M, H, and VH) were
assigned based on empirical data. Endpoints in black italics (VL, L, M, H, and VH) were assigned using values from predictive models and/or professional judgment.
This table contains hazard information for each chemical; evaluation of risk considers both hazard and exposure. Variations in end-of-life processes or degradation and combustion
by-products are discussed in the report but not addressed directly in the hazard profiles. The caveats listed below must be taken into account when interpreting the information in the
table.
§ Based on analogy to experimental data for a structurally similar compound. R Recalcitrant: Substance is comprised of metallic species (or metalloids) that will not degrade, but may
change oxidation state or undergo complexation processes under environmental conditions. °Concern linked to direct lung effects associated with the inhalation of poorly soluble
particles less than 10 microns in diameter.A Depending on the grade or purity of amorphous silicon dioxide commercial products, the crystalline form of silicon dioxide may be
present. The hazard designations for crystalline silicon dioxide differ from those of amorphous silicon dioxide, as follows: VERY HIGH (experimental) for carcinogenicity; HIGH
(experimental) genotoxicity; MODERATE (experimental) for acute toxicity and eye irritation.
Chemical
CASRN
Human Health Effects
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4-316
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Silicon Dioxide (amorphous)
O-
'Si
-
* indicates repeating units with indeterminate structure
CASRN: 7631-86-9
MW: 60.09 (for SiO2)
MF: (Si02)n
Physical Forms:
Neat: Solid
Use: Flame retardant
SMILES: Not applicable
Synonyms: Silica (CASRN 7631-86-9)
Silicon dioxide, amorphous: Silica, amorphous fumed, crystalline-free (CASRN 112945-52-5); Pyrogenic (fumed) amorphous silica (CASRN 112945-52-5); Silica,
vitreous (CASRN 60676-86-0); Amorphous silica gel, crystalline-free (CASRN 112926-00-8); Silica gel, precipitated, crystalline-free (CASRN 112926-00-8); Silica,
amorphous, diatomaceous earth (CASRN 61790-53-2); Silica, amorphous, flux-calcined diatomaceous earth (CASRN 68855-54-9)
Silicon dioxide, crystalline: Silica, crystalline, cristobalite (CASRN 14464-46-1), Silica, crystalline, tripoli (CASRN 1317-95-9); Silica, crystalline, tridymite
(CASRN 15468-32-3); Quartz (CASRN 14808-60-7); Sand
Trade names:
Silicon dioxide, amorphous: Aerosil, Art Sorb, Baykisol, Bindzil, Biogenic silica, Britesorb, Cab-O-Sil, Celatom, Celite, Clarcel, Colloidasilica, Decalite, Diamantgel,
Diatomaceous earth (flux-calcined), Diatomaceous earth (uncalcined), Diatomite, Fina/Optima, FK, Fused silica, Gasil, HDK, Hi-Sil, Hispacil, KC-Trockenperlen,
Ketjensil, Kieselguhr, Lucilite, Ludox, Nalcoag, Neosyl, Nipsil, Nyacol, Opal, Precipitated silica, Quartz glass, Reolosil, Seahostar, Sident, Silcron, Silica fibres
(biogenic), Silica-Perlen, Silica-Pulver, Sipernat, Skamol, Snowtex, Spherosil, Suprasil, Sylobloc, Syloid, Sylopute, Syton, TAFQ, Tixosil, Tripolite, Trisyl, Ultrasil
Silicon dioxide, crystalline: Agate, Chalcedony, Chert, Clathrasil, Coesite, alpha, beta Cristobalite, CSQZ, DQ 12, Flint, Jasper, Keatite, Min-U-Sil, Moganite,
Novaculite, Porosil, alpha-Quartz, alpha, beta Quartz, Quartzite, Sandstone, Sil-Co-Sil, Silica sand, Silica W, Snowit, Stishovite, Sykron F300, Sykron F600, alpha,
betal, beta2 Tridymite, Zeosil
Chemical Considerations: Silicon dioxide (also known as silica) is an inorganic compound that exists in several physical forms. This report assesses silicon dioxide
for flame retardant applications, in which amorphous silicon dioxide is more commonly used. Commercial products may contain crystalline silicon dioxide, depending
on the purity and grade.
Silicon dioxide, amorphous consists of randomly arranged rings of silicon dioxide that form a complex structure of roughly spherical particles. Silicon dioxide,
crystalline; however is a general term that refers to the many distinct crystal structures or polymorphs of silicon dioxide. Crystalline silicon dioxide includes naturally
occurring quartz (CASRN 14808-60-7), cristobalite (CASRN 14464-46-1), and tridymite (CASRN 15468-32-3).
The structural form of silicon dioxide is evaluated in this assessment as it influences the hazards posed to human health. It may be difficult for supply chains to know
the difference between the structural forms. Therefore, the hazard designations in this report are based on the amorphous form and a summary of the hazards
associated with the crystalline form is provided in the hazard summary table as a footnote () for reference, in case the crystalline form is present in the commercial
formulation. Concerns based on the nanoscale material were not included in this assessment; however, the potential health concerns from the inhalation of finely
divided particulates that are generally less than 10 microns in diameter were considered for human health endpoints.
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Although not all literature entries identified which form of silicon dioxide was being discussed, this information was provided whenever available. In the absence of
experimental data, structural considerations associated with this mineral were used to complete this hazard profile (IARC, 1997; HSDB, 2009; Waddell, 2013).
Polymeric: No
Oligomeric: Not applicable
Metabolites, Degradates and Transformation Products: None identified.
Analog: Confidential analogs; a general silicon dioxide CASRN is used to
represent all forms of silicon dioxide (CASRN 7631-86-9). Other CASRN for
specific silicon dioxide forms are listed in the synonyms section and noted in the
data quality column for relevant entries.
Endpoint(s) using analog values: Neurotoxicity
Analog Structure: Not applicable
Structural Alerts: Respirable, poorly soluble particulates - Human health, limited to effects on the lung as a result of inhaling the
particles (EPA, 2010).
Risk Phrases: Not classified by Annex VI Regulation (EC) No 1272/2008 (ESIS, 2012).
Hazard and Risk Assessments: An Organisation for Economic Co-operation and Development (OECD) Screening Information Dataset Initial Assessment Profile
(SIAP) for silicon dioxide was completed in 2004. Silicon dioxide is included in the International Agency for Research on Cancer (IARC) monographs on the
evaluation of carcinogenic risks to humans - summaries and evaluations. (IARC, 1997; OECD SIDS, 2004a).
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
PHYSICAL/CHEMICAL PROPERTIES
Melting Point (°C)
Boiling Point (°C)
Vapor Pressure (mm Hg)
Water Solubility (mg/L)
1,710 (Measured)
Crystalline silicon dioxide: 1,400-2,000
(Measured)
2,230 (Measured)
Amorphous and crystalline silicon
dioxide:
-------
Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
Log Kow
Flammability (Flash Point)
Explosivity
Pyrolysis
pH
pKa
DATA
Practically insoluble (Estimated)
Amorphous silicon dioxide: Used as a
fire-extinguishing agent, not combustible,
stable (Measured)
Amorphous and crystalline silicon
dioxide: Silicon dioxide is a fully
oxidized inorganic material and is not
expected to be explosive. (Estimated)
Amorphous and crystalline silicon
dioxide: Not applicable (Estimated)
3.5-9 for 5% aqueous suspension of wet
process silica. (Measured)
3.6-4.5 for 4% aqueous suspension of
fumed silica. (Measured)
REFERENCE
Merck, 1996
Daubert and Banner, 1989 (as
cited in ECHA, 2013)
Professional judgment
Professional judgment
EC, 2000a
EC, 2000a
DATA QUALITY
Adequate, non-quantitative value
provided. Test substance form not
specified.
No data located.
Reported in a secondary source for
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5) and Silica gel, precipitated,
crystalline-free (CASRN 112926-
00-8).
No experimental data located; based
on its chemical structure and use as
a flame retardant.
Inorganic compounds do not
undergo pyrolysis.
Adequate values reported in a
secondary source. The values of 20
different types of wet process silica,
identified only by trade names, fall
within this range.
Adequate value reported in a
secondary source for fumed silica.
No data located.
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
Particle Size
DATA
Amorphous silicon dioxide:
D10 = <103 (im
D50 = <211 nm
D99 = <610(im
According to ISO 13320-1 (Part 1):
Particle size analysis - Laser diffraction
methods; OECD guideline 110: Particle
size distribution / fibre length and
diameter distributions and EN 481 (1993):
Workplaces atmospheres; size fraction
definitions for measurement of airborne
particles. (Measured)
Amorphous silicon dioxide:
D10 = <230(im
D50 = <615 (im
D99 = 99.8 %
SiO2 with limited study details.
Adequate guideline study reported
for Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5).
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
size distribution / fibre length and
diameter distributions and EN 481 (1993):
Workplaces atmospheres; size fraction
definitions for measurement of airborne
particles. (Measured)
Amorphous silicon dioxide:
ECHA, 2013
D90.6 = 2,000 (im
According to ISO 13320-1 (Part 1):
Particle size analysis - Laser diffraction
methods; OECD guideline 110: Particle
size distribution / fibre length and
diameter distributions and EN 481 (1993):
Workplaces atmospheres; size fraction
definitions for measurement of airborne
particles. (Measured)
Amorphous silicon dioxide:
ECHA, 2013
D50 = <480
According to ISO 13320-1 (Part 1):
Particle size analysis - Laser diffraction
methods; OECD guideline 110: Particle
size distribution / fibre length and
diameter distributions and EN 481 (1993):
Workplaces atmospheres; size fraction
definitions for measurement of airborne
particles. (Measured)
Amorphous silicon dioxide:
D 14.04 = <0.64(im
100 = <10.23(im
Using Anderson 7-stage cascade impactor
(Measured)
ECHA, 2013
Amorphous silicon dioxide:
Typical size ranges of:
ECHA, 2013
4-322
Adequate guideline study reported
for the commercial product HDK
T30: >99.8 % SiO2, Silica,
amorphous, fumed, crystalline-free
(CASRN 112945-52-5).
Reported for Syloid 74, CAS-Name:
Silica gel, crystalline-free; (CASRN
112926-00-8), purity ca. 100 %.
Non guideline study reported for
HDK T30: >99.8 % SiO2; Silica,
amorphous, fumed, crystalline-free;
(CASRN 112945-52-5).
Reported for Silica, amorphous,
fumed, crystalline-free (CASRN
-------
Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
0.1 - 1 (im for aggregates;
1 - 250 (im for Agglomerates
(Measured)
Amorphous silicon dioxide:
Typical size ranges of:
0.1-1 (im for aggregates;
1 - 250 (im for Agglomerates
1-20 (im for silica gel aggregates
(Measured)
REFERENCE
ECHA, 2013
DATA QUALITY
112945-52-5).
Reported for Silica gel and
amorphous silica, precipitated,
crystalline-free (CASRN 112926-
00-8) with limited study details.
HUMAN HEALTH EFFECTS
Toxicokinetics
Dermal Absorption in vitro
Absorption,
Distribution,
Metabolism &
Excretion
Oral, Dermal or Inhaled
Amorphous silicon dioxide (CASRNs 7631-86-9, 112945-52-5, 112926-00-8) is rapidly eliminated from the
lung tissue. Disposition in the mediastinal lymph nodes is substantial during and after prolonged
inhalation exposures in experimental animals; however the involvement of lymphatic elimination is not as
relevant following short exposure periods. Intestinal absorption of amorphous silicon dioxide is limited in
animals and humans, and there is evidence of ready renal elimination of the bioavailable fractions of silica.
In contrast, crystalline silicon dioxide forms tend to accumulate and persist in the lung and lymph nodes.
Amorphous silicon dioxide: After
prolonged exposure of rats to high
concentrations of amorphous silica (40-50
mg/m3), overall elimination was high and
was not found to accumulate in the lung:
only 5-6% of respirable material was
found after 120 exposure days. On the
other hand, following prolonged
exposure, there was substantial transfer to
mediastinal lymph nodes with about 31%
of total deposit = 1.5- 2% of the respirable
material. The involvement of lymphatic
elimination after short exposures is not as
relevant, particularly when there is a
lower body burden of amorphous silica.
Amorphous and crystalline silicon
dioxide: Crystalline forms of silicon
dioxide have a tendency to accumulate
OECD SIDS, 2004b
OECD SIDS, 2004a; OECD
SIDS, 2004b
Sufficient study details reported in a
secondary source. Aerosil 150,
pyrogenic silica (CASRN 112945-
52-5).
Sufficient study details reported in a
secondary source. Data are for
synthetic amorphous silica and
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
and persist in the lung and lymph nodes.
Intestinal absorption of silicon dioxide is
insignificant in animals and humans.
There is evidence of renal elimination of
the bioavailable fractions
Amorphous silicon dioxide: Female
Sprague-Dawley rats exposed via
inhalation to HDK V15 dust at a
concentration of 50 - 55 mg/m3 (nominal,
respirable about 30 mg/m3 with
aerodynamic diameter of <7 (im) for 12
months. No substantial increase in the
SiO2 deposition in the lung and the
mediastinal lymph nodes were observed
between exposure of 18 weeks and of 12
months. About 90 % of the SiO2 was
cleared from the lungs and 50 - 60% from
the mediastinal lymph nodes within 5
months. This corresponds to an
approximate half-life of 7 weeks, based
on first-order elimination kinetics.
ECHA, 2013
Amorphous silicon dioxide: Fischer 344
rats exposed via inhalation to Aerosil 200
dust at a concentration of 50.4 mg/m3 6
hours/day, 5 days/week for 13 weeks.
Lung burdens during treatment were as
follows: 755.9 jig at 6.5 weeks and 88.27
(ig at 13 weeks of exposure. Lung
burdens following treatment were 156.0
(ig at 12 weeks and 92.6 (ig at 32 weeks
post- exposure (during the recovery
phase).
ECHA, 2013
Amorphous silicon dioxide: Wistar rats
exposed via inhalation to Aerosil 200 at
concentrations of 0, 1.3, 5.9 or 31 mg/m3
for 90 days. Half-life was rapid from the
ECHA, 2013
crystalline silica.
Sufficient study details reported in a
secondary source. HDK V15: >99.8
% SiO2, 150 m2/g (BET), CAS-
Name: Silica, amorphous fumed,
crystalline-free (CASRN 112945-
52-5).
Sufficient study details reported in a
secondary source. Aerosil 200:
CAS-Name: Silica, amorphous,
fumed, crystalline-free (CASRN
112945-52-5).
Sufficient study details reported in a
secondary source. Aerosil 200:
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
4-324
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
lungs; No bioaccumulation potential
based on study results.
Amorphous silicon dioxide: Rats
receiving 20 daily oral doses of 100 mg
HDK V15 per animal (about 500 mg/kg
bw) each; tissue values (SiO2) apparently
were very slightly increased in liver and
kidney: in liver 4.2 (ig (control value 1.8
(ig), in the spleen 5.5 (ig (7.2 (ig) and in
the kidneys 14.2 (ig (7.8 (ig).
ECHA, 2013
Amorphous silicon dioxide: Human
subjects (10 males and 2 females per test
article) were given Aerosil or FK 700 as
0.5% suspensions in apple juice. Urinary
excretion for both test substances was
<0.5 % of the dose within 4 days. Overall.
increases in excretion of SiO2 after oral
ingestion were not unequivocally
detectable.
ECHA, 2013
Amorphous silicon dioxide: Silicon
dioxide is slowly absorbed from dusts
deposited in lungs, or from material taken
orally.
HSDB, 2009
52-5).
Sufficient study details reported in a
secondary source. HDK V15: >99.8
% SiO2, 150 m2/g (BET), CAS-
Name: Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5).
Sufficient study details reported in a
secondary source. Aerosil, CAS-
Name: Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5); or FK 700, Silica gel,
precipitated, crystalline-free
(CASRN 112926-00-8).
Limited data reported in a secondary
source for amorphous silica.
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
Other
Acute Mammalian Toxicity
Acute Lethality
Oral
Dermal
DATA
Amorphous silicon dioxide: Amorphous
silica (HDK VI 5), 10 mg subcutaneously
injected in 0.3 mL water in female
Sprague-Dawley rats, was rapidly
removed from the site of injection: mean
recovery 24 h post-treatment 6.90 mg,
after one month 0.65 mg (approx. 10 %
left) and after two months 0.30 mg (less
than 5 % left) Similar results were
obtained in rats after subcutaneous
application of 30, 40, and 50 mg
AEROSIL 150 as suspension in water or
in 0.5% Tween or as dry powder
(operative, subcutaneous): after 6 weeks
95 - 97 % of the substance was
eliminated.
REFERENCE
OECD SIDS, 2004b
DATA QUALITY
Sufficient study details reported in a
secondary source. HDK V15: >99.8
% SiO2, 150 m2/g (BET), CAS-
Name: Silica, amorphous, fumed
(CASRN 112945-52-5).
LOW: Amorphous silicon dioxide is not acutely toxic when administered via oral, dermal, or inhalation
routes. If the crystalline form of silicon dioxide is present, the hazard designation is Moderate based on an
oral LD50 of 500 mg/kg and lung effects following short-term inhalation exposure.
Amorphous silicon dioxide: Mouse oral
LD50>3, 160 mg/kg
Amorphous silicon dioxide: Rat oral
LD50 >3,300 - >20,000 mg/kg
Amorphous silicon dioxide: Rat oral
LD0 >3,300 - >40,000 mg/kg
Crystalline silicon dioxide: Rat oral
LD50 = 500 mg/kg
Amorphous silicon dioxide: Rabbit
ECHA, 2013
EC, 2000a;ECHA, 2013
EC, 2000a
EC, 2000b
EC,2000a;Waddell,2013
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5).
Sufficient study details reported in a
secondary source. Silica,
precipitated, crystalline-free
(CASRN 112926-00-8).
Sufficient study details reported in a
secondary source. Amorphous
(CASRN 7631-86-9) or Silica,
precipitated, crystalline-free
(CASRN 112926-00-8).
Study details reported in a
secondary source; particle size of
quartz was 100-200 (im.
Sufficient study details reported in a
4-326
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Inhalation
dermal LD50 >2,000 - >5,000 mg/kg
secondary source. Silica,
precipitated, crystalline-free
(CASRN 112926-00-8).
Amorphous silicon dioxide: Rat 4-hour
inhalation LC50 >58.8 mg/L (nominal,
nose only, dust);
4-hour LC0 >58.8 mg/L (nominal)
ECHA, 2013
Sufficient study details reported in a
secondary source. Silica,
amorphous, fumed, crystalline-free
(CASRN 112945-52-5), purity ca.
100 %.
Amorphous silicon dioxide: Rat 4-hour
inhalation LC0 >0.139 - >0.69 mg/L
(nose only, dust);
Rat 1-hour inhalation LC0 >0.139;
Rat 7-hour inhalation LC0 >0.139 - >3.1
mg/L
EC, 2000a; ECHA, 2013
Sufficient study details reported in a
secondary source. Silica,
precipitated, crystalline-free
(CASRN 112926-00-8) or Silica,
amorphous, fumed, crystalline-free
(CASRN 112945-52-5).
Amorphous silicon dioxide: Rat 1-hour
inhalation LC50 >2.2 mg/L
ECHA, 2013
Insufficient study; significant
methodological deficiencies. Silica
gel, crystalline-free (CASRN
112926-00-8).
Crystalline silicon dioxide: 3-day
inhalation study in rats exposed to 0, 10,
or 100 mg/m3 of cristobalite (6
hours/day). Increased granulocytes and
other markers of cytotoxicity from the
lung lavage fluid were reported in all
treated animals.
LOAEC: 10 mg/m3 (0.01 mg/L)
OECDSIDS, 2011
Limited study details reported in a
secondary source; test substance
identified as cristobalite; an LC50
was not calculated for this study, but
supports a Moderate hazard
designation for the inhalation route.
Carcinogenicity
LOW: Based on the weight of evidence, amorphous silicon dioxide has a Low potential for carcinogenicity.
Amorphous silicon dioxide was not carcinogenic in rats or mice following dietary administration for 103 or
93 weeks, respectively. Amorphous silicon dioxide is not classifiable as to its carcinogenicity to humans.
Crystalline silicon dioxide was carcinogenic in several inhalation studies in rats and was shown to have an
excess cancer risk following workplace exposure in several epidemiology studies. In addition, estimation
software predicts a high-moderate carcinogenic risk for crystalline silicon dioxide. If the crystalline form
of silicon dioxide is present, a VERY HIGH hazard designation would be assigned based on the weight of
evidence that indicates sufficient evidence of carcinogenicity in humans.
4-327
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
OncoLogic Results
Amorphous silicon dioxide:
OncoLogic, 2008
This compound is not amenable to
available estimation methods.
Crystalline silicon dioxide: High-
moderate; there is clear evidence that
crystalline silica is a human and animal
carcinogen via the inhalation route.
(Estimated)
OncoLogic, 2008
Estimated based on silica,
crystalline (CASRN 14808-60-7).
Carcinogenicity (Rat and
Mouse)
Amorphous silicon dioxide: In a 103
week study, Fischer 344 rats
(40/sex/dose) were fed 0, 0.125, 2.5 and
5% Syloid 244 in the diet daily. The mean
daily intake was 143.46, 279.55 and
581.18 g/rat in males and 107.25,205.02
and 435.33 g/rat in females, respectively.
The tumor response was not statistically
different from controls.
EC, 2000a;ECHA, 2013
Sufficient study details reported in a
secondary source. Syloid 244: Silica
gel, crystalline-free (CASRN
112926-00-8).
Amorphous silicon dioxide: In a 93-
week study, B6C3F1 mice (40/sex/group)
were fed 0, 1.25, 2.5 and 5 % Syloid 244
in the diet daily. The mean cumulative
intake after 93 weeks was 38.45, 79.78
and 160 g/mouse in males and 37.02,
72.46 and 157.59 g/mouse in females,
respectively. No significant difference in
survival rats or behavior was observed.
No dose-related alteration in hematologic
parameters or organ weights. Malignant
lymphoma/leukemia, which occurred in
7/20 females in the 2.5% dose group, was
not statistically different than controls.
Non-neoplastic lesions were considered to
be of no toxicological significance.
EC, 2000a;ECHA, 2013
Sufficient study details reported in a
secondary source. Syloid 244: Silica
gel, crystalline-free (CASRN
112926-00-8).
Amorphous silicon dioxide: Intrapleural
implantation of synthetic amorphous
4-328
IARC, 1997
Reported in a secondary source; test
substance specified as amorphous
-------
Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
silica was negative for tumorigenesis.
silica.
Amorphous silicon dioxide: Oral
administration of food-grade, micronized,
amorphous silica to rats and mice was
negative for tumorigenesis.
IARC, 1997
Reported in a secondary source; test
substance specified as amorphous
silica.
Amorphous silicon dioxide: Slightly
increased incidence of intra-abdominal
lymphosarcomas was reported after
intraperitoneal injection of diatomaceous
earth to mice. Subcutaneous and oral
administration in mice produced no
increase in tumors.
IARC, 1997
Reported in a secondary source; test
substance specified as amorphous
silica.
Crystalline silicon dioxide: Several
epidemiological investigations have
shown an excess cancer risk following
workplace inhalational exposure to dust
containing respirable crystalline silica.
Lung cancer incidence tended to increase
with cumulative exposure; increased
duration of exposure; peak intensity of
exposure; presence of radiographically
defined silicosis; and length of follow-up
time from date of silicosis diagnosis.
IARC, 1997; OECD SIDS, 2011
Reported in a secondary source; test
substance specified as crystalline
silica.
Crystalline silicon dioxide: Study with
Balb/x mice (8 hours/day, 5 days/week in
three groups of 6 to 16 mice at a
concentration of 475 mg/m3 for 150 days,
1,800 mg/m3 for 300 days or 1,950 mg/m3
for 570 days. There was no statistically
significant difference in the number of
pulmonary adenomas reported in the
control or treated groups.
EC, 2000b
Limited study details reported in a
secondary source.
Crystalline silicon dioxide: 2-year study
with F344 rats (50/sex), exposed via
whole body inhalation for 6 hours/day, 5
EC, 2000b; OECD SIDS, 2011
Limited study details reported in a
secondary source.
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
days/week at a concentration of 1 mg/m3.
Inhalation exposure caused primary lung
tumors (majority were adenocarcinomas)
in 18 animals (12 in females, 5 in males).
Mean mass of particles in the lungs at the
end of the exposure period was 0.91
mg/lung.
Crystalline silicon dioxide: Four
experiments in rats by inhalation of quartz
and four experiments in rats by
intratracheal instillation of quartz
produced increased incidences of
adenocarcinomas and squamous-cell
carcinomas of the lungs. Animals that
developed tumors also showed fibrosis.
For the intratracheal instillation studies,
doses ranged from 4 to 57 mg/kg-bw (7,
12 or 20 mg/animal of Min-U-Sil (5)
quartz or 20 mg/animal of novaculite
quartz). Exposure ranged from single
instillation with observation for up to two
years, to weekly instillation for 10 weeks.
There was an increased incidence of
silicotic granulomas after 3 weeks and
lung tumors after 11 months following
single intratracheal administration of a
95% pure quartz particles (<5 (im).
IARC, 1997; OECD SIDS, 2011
Reported in a secondary source; test
substance specified as crystalline
silica.
Crystalline silicon dioxide: Thoracic and
abdominal malignant lymphomas,
primarily of the histiocytic type (MLHT)
were found following intrapleural or
intraperitoneal injections of several types
of quartz to rats.
IARC, 1997
Reported in a secondary source; test
substance specified as crystalline
silica.
Combined Chronic
Toxicity/Carcinogenicity
No data located.
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Other
Amorphous silicon dioxide:
Amorphous silica is not classifiable as to
its carcinogenicity to humans (Group 3:
This category is used most commonly for
agents for which the evidence of
carcinogenicity is inadequate in humans
and inadequate or limited in experimental
animals.
Exceptionally, agents for which the
evidence of carcinogenicity is inadequate
in humans but sufficient in experimental
animals may be placed in this category
when there is strong evidence that the
mechanism of carcinogenicity in
experimental animals does not operate in
humans. Agents that do not fall into any
other group are also placed in this
category.
An evaluation in Group 3 is not a
determination of non-carcinogenicity or
overall safety. It often means that further
research is needed, especially when
exposures are widespread or the cancer
data are consistent with differing
interpretations).
IARC, 1997
Summarized from a secondary
source.
Crystalline silicon dioxide: Crystalline
silica inhaled in the form of quartz or
cristobalite from occupational sources is
carcinogenic to humans (Group 1: This
category is used when there is sufficient
evidence of carcinogenicity in humans.
Exceptionally, an agent may be placed in
this category when evidence of
carcinogenicity in humans is less than
IARC, 1997
Summarized from a secondary
source.
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
sufficient but there is sufficient evidence
of carcinogenicity in experimental
animals and strong evidence in exposed
humans that the agent acts through a
relevant mechanism of carcinogenicity).
Genotoxicity
LOW: Based on the weight of evidence, amorphous silicon dioxide was negative both in vitro and in vivo
gene mutation and chromosome aberration assays.
If crystalline silicon dioxide is present, the hazard designation is assigned a HIGH based on weight of
evidence from multiple studies. Crystalline silicon dioxide induced gene mutations in vivo and
chromosomal aberrations in several in vitro and in vivo studies in experimental animals. In addition,
crystalline silicon dioxide induced cell transformation in mice and hamsters in vitro.
Gene Mutation in vitro
Amorphous silicon dioxide: Negative in
Escherichia coll WP2 with and without
metabolic activation.
Test concentrations: 0.033 - lOmg/plate,
suspended in DMSO.
Amorphous silicon dioxide: Negative in
HGPRT assay in Chinese hamster ovary
(CHO) cells with and without metabolic
activation.
Test concentrations: 10, 50, 100, 150, and
250 (ig/mL (without S9) and 100, 200,
300, 400, and 500 (ig/mL (with S9).
Amorphous silicon dioxide: Negative in
Saccharomyces cerevisiae strains TA98,
TA100, TA1535, TA1537 and TA1538
with and without metabolic activation.
Test concentrations: 667, 1,000, 3,333,
6,667, and 10,000 (ig/plate
Amorphous silicon dioxide: Negative in
Salmonella typhimurium and Escherichia
coli mutagenicity assay.
Crystalline silicon dioxide: Direct
treatment of rat lung epithelial cells with
IARC, 1997; EC, 2000a; ECHA,
2013
EC, 2000a; ECHA, 2013
EC, 2000a; ECHA, 2013
IARC, 1987
IARC, 1987
Sufficient study details reported in a
secondary source. Silcron G-190
(SCM Glidden): Silica gel,
crystalline-free (CASRN 112926-
00-8).
Sufficient study details reported in a
secondary source. Cab-O-Sil EH-5:
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5).
Sufficient study details reported in a
secondary source. Silcron G-190
(SCM Glidden): Silica gel,
crystalline-free (CASRN 112926-
00-8).
Study details reported in a
secondary source; test substance
amorphous silica.
Study details reported in a
secondary source; test substance
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Gene Mutation in vivo
quartz in vitro did not cause HPRT
mutation.
Crystalline silicon dioxide: Negative;
Salmonella typhimurium reverse mutation
assay (with or without metabolic
activation)
EC, 2000b
Amorphous silicon dioxide: Negative;
alveolar type-II cells isolated from rats
exposed via whole body inhalation to 50-
mg/m3 Aerosil 200 showed no increased
mutation frequency. Exposure was for 6
hours/day, 5 days/week for 13 weeks.
Crystalline silica was examined
simultaneously as a positive control.
ECHA, 2013
Amorphous silicon dioxide: Negative,
gene mutations in host mediated assay;
male ICR mice orally gavaged with 1.4,
14, 140, 500 and 5,000 mg/kg suspended
in 0.85 % saline and then injected with
Salmonella typhimurium or
Saccharomyces cerevisiae.
ECHA, 2013
Crystalline silicon dioxide: Epithelial
cells from the lungs of rats intratracheally
exposed to quartz showed HPRT gene
mutations.
IARC, 1997
crystalline silica.
Limited study details reported in a
secondary source.
Sufficient study details reported in a
secondary source. Aerosil 200:
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5).
Sufficient study details reported in a
secondary source. Syloid 244: Silica
gel, crystalline-free (CASRN
112926-00-8).
Study details reported in a
secondary source; test substance
crystalline silica.
Chromosomal Aberrations in
vitro
Amorphous silicon dioxide: Negative
for chromosomal aberrations in human
embryonic lung cells (Wi-38) without
metabolic activation. Test concentrations:
0.1, 1.0, and 10 (ig/mL.
EC, 2000a; ECHA, 2013
Sufficient study details reported in a
secondary source. Syloid 244: Silica
gel, crystalline-free (CASRN
112926-00-8).
Amorphous silicon dioxide: Negative
for chromosomal aberrations in CHO
cells with and without metabolic
activation;
Test concentrations: 38, 75, 150, 300
EC, 2000a; ECHA, 2013
Sufficient study details reported in a
secondary source. Silica,
amorphous, fumed, crystalline-free
(CASRN 112945-52-5).
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
(ig/mL (without S9) and 250, 500, 750,
1,000 (ig/mL (with S9).
Crystalline silicon dioxide: Tridymite
induced sister chromatid exchange in co-
cultures of human lymphocytes and
monocytes.
IARC, 1997
Crystalline silicon dioxide: Induces
micronuclei in Syrian hamster embryo
cells, Chinese hamster lung V79 cells,
and human embryonic lung Hel 299 cells
in vitro, but negative for inducing
chromosomal aberrations.
IARC, 1997
Crystalline silicon dioxide: Induced
micronuclei in Syrian hamster embryo
cells
EC, 2000b
Chromosomal Aberrations in
vivo
Amorphous silicon dioxide: Negative,
chromosomal aberration dominant lethal
assay in rats orally gavaged with 1.4,
14.0, 140, 500 and 5,000 mg/kg
suspended in 0.85 % saline.
ECHA, 2013
Crystalline silicon dioxide: Induced
chromosomal aberrations in human
peripheral blood lymphocytes following
in vivo exposure to dust containing
crystalline silica.
IARC, 1997
Crystalline silicon dioxide: Positive,
induced sister chromatid exchange in
human peripheral blood lymphocytes
following in vivo exposure to dust
containing crystalline silica.
IARC, 1997
Crystalline silicon dioxide: Quartz did
not induce micronuclei in mice in vivo.
IARC, 1997
Study details reported in a
secondary source; test substance
crystalline silica.
Study details reported in a
secondary source; test substance
crystalline silica.
Limited study details reported in a
secondary source; route and
duration of exposure were not
specified.
Sufficient study details reported in a
secondary source. Syloid 244: Silica
gel, crystalline-free (CASRN
112926-00-8).
Study details reported in a
secondary source; test substance
crystalline silica.
Study details reported in a
secondary source; test substance
crystalline silica.
Study details reported in a
secondary source; test substance
crystalline silica.
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DNA Damage and Repair
Other
DATA
Crystalline silicon dioxide: Negative;
did not cause sister chromatid exchange
or aneuploidy in Syrian hamsters exposed
to 2 (ig in vivo.
Crystalline silicon dioxide: Negative;
did not cause sister chromatid exchanges
in Chinese hamsters
Crystalline silicon dioxide: DQ 12
quartz did not induce micronuclei in
polychromatic erythrocytes of bone
marrow of mice at 500 mg/kg bw.
Negative for chromosomal aberrations in
two assays following single and subacute
oral gavage administration to rats.
Crystalline silicon dioxide: Five quartz
samples induced transformation in
BALB/C-3T3 cells in vitro.
Crystalline silicon dioxide: Two quartz
samples induced morphological
transformation in Syrian hamster cells in
vitro.
Negative, unscheduled DNA synthesis
assay in primary rat hepatocytes.
Negative in two dominant lethal assays in
rats following oral gavage administration.
REFERENCE
EC, 2000b
EC, 2000b
EC, 2000b
IARC, 1997
IARC, 1997
IARC, 1997
EC, 2000a
EC, 2000a
DATA QUALITY
Limited study details reported in a
secondary source; route of
administration, exposure duration
was not specified.
Limited study details reported in a
secondary source; route of
administration and exposure
duration were not specified.
Limited study details reported in a
secondary source.
Secondary source, study details and
test conditions were not provided.
The original study was in an
unpublished report. Test substance
unspecified silica.
No data located.
Study details reported in a
secondary source; test substance
crystalline silica.
Study details reported in a
secondary source; test substance
crystalline silica.
Secondary source, study details and
test conditions were not provided.
The original study was in an
unpublished report. Test substance
unspecified silica.
Secondary source, study details and
test conditions were not provided.
The original study was in an
unpublished report. Test substance
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
Reproductive Effects
Reproduction/Developmental
Toxicity Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Reproduction and Fertility
Effects
Other
DATA
REFERENCE
DATA QUALITY
unspecified silica.
LOW: There was no indication of adverse reproductive effects in an unpublished one-generation oral
study in rats administered amorphous silica, fumed.
It is estimated that crystalline silicon dioxide, if present, is not likely to produce reproductive effects based
on analogy to amorphous silicon dioxide and professional judgment.
Amorphous silicon dioxide: In a one-
generation oral dietary study, Wistar rats
(5 females, 1 male/dose) were fed test
substance at doses of 0, 497 mg/kg bw
(males) or 509 mg/kg bw (females) in the
diet daily. In parents: no clinical signs of
toxicity, no mortality, no abnormalities in
body-weight gain and feed consumption,
no hematological findings. In pups: no
behavioral or developmental/structural
abnormalities.
NOAEL (parental and offspring): 497
mg/kg-day (males); 509 mg/kg bw-day
(females) (highest concentrations tested)
LOAEL: Not established
Crystalline silicon dioxide: There is low
potential for reproductive effects based on
analogy to amorphous silicon dioxide.
(Estimated by analogy)
EC, 2000a;ECHA, 2013
Professional judgment
No data located.
No data located.
Significant methodological
deficiencies, acceptable as
screening. Aerosil, not further
specified, hydrophilic: CAS-Name:
Silica, amorphous, fumed,
crystalline free (CASRN 112945-
52-5).
Estimated based on analogy to
amorphous silicon dioxide and
professional judgment; no
experimental data located.
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Developmental Effects
LOW: Amorphous silicon dioxide did not produce adverse developmental effects in rats, mice, rabbits or
hamsters following oral administration at doses up to 1,600 mg/kg bw-day during gestation. It is estimated
that crystalline silicon dioxide, if present, is not likely to produce developmental effects based on analogy
to amorphous silicon dioxide and professional judgment.
There were no data located for the developmental neurotoxicity endpoint.
Reproduction/
Developmental Toxicity
Screen
Combined Repeated Dose
with Reproduction/
Developmental Toxicity
Screen
Prenatal Development
Amorphous silicon dioxide: Pregnant
CD-I mice (21-26 females/group) were
administered Syloid 244 via oral gavage
at doses of 0, 13.4, 62.3, 289 and 1,340
mg/kg bw-day from gestation days 6-15.
The number of abnormalities seen in
either soft or skeletal tissues of the test
groups did not differ from the number
occurring spontaneously in controls.
NOAEL (maternal and fetal): 1,340
mg/kg-day (highest dose tested)
LOAEL: Not established
Amorphous silicon dioxide: Pregnant
Wistar rats (20/25 females/group) were
administered Syloid 244 via oral gavage
at doses of 0, 13.5, 62.7, 292 and 1,350
mg/kg bw-day from gestation days 6-15.
No observable effects on maternal or fetal
survival or development. The number of
abnormalities seen in either soft or
skeletal tissues of the test groups did not
No data located.
No data located.
EC, 2000a:ECHA, 2013
EC, 2000a;ECHA, 2013
Sufficient study details reported in a
secondary source. Syloid 244: Silica
gel, crystalline-free (CASRN
112926-00-8).
Sufficient study details reported in a
secondary source. Syloid 244: Silica
gel, crystalline-free (CASRN
112926-00-8).
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Postnatal Development
Prenatal and Postnatal
Development
differ from the number occurring
spontaneously controls.
NOAEL (maternal and fetal): 1,350
mg/kg-day (highest dose tested)
LOAEL: Not established
Amorphous silicon dioxide: Pregnant
Dutch rabbits (10-14/dose) were
administered Syloid 244 via oral gavage
at doses of 0, 16.0, 74.3, 345 and 1,600
mg/kg bw-day from gestation days 6-18.
No adverse effect on maternal or fetal
survival. The number of abnormalities
seen in either soft or skeletal tissues of the
test groups did not differ from the number
occurring spontaneously in controls.
NOAEL (maternal and fetal): 1,600
mg/kg bw-day (highest dose tested)
LOAEL: Not established
EC, 2000a;ECHA, 2013
Sufficient study details reported in a
secondary source. Syloid 244: Silica
gel, crystalline-free (CASRN
112926-00-8).
Amorphous silicon dioxide: Pregnant
Syrian hamsters (21-22 females/group)
were administered Syloid 244 via oral
gavage at doses of 0, 16.0, 74.3, 345 and
1,600 mg/kg bw-day from gestations days
6-10. The number of abnormalities seen
in either soft or skeletal tissues of the test
groups did not differ from the number
occurring spontaneously in controls.
NOAEL (maternal and fetal): 1,600
mg/kg-day (highest dose tested)
LOAEL: Not established
EC, 2000a:ECHA, 2013
Sufficient study details reported in a
secondary source. Syloid 244: Silica
gel, crystalline-free (CASRN
112926-00-8).
No data located.
No data located.
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
Developmental Neurotoxicity
Other
Neurotoxicity
Neurotoxicity Screening
Battery (Adult)
Other
Repeated Dose Effects
DATA
No data were located for the
developmental neurotoxicity endpoint.
Crystalline silicon dioxide: There is low
potential for developmental effects based
on analogy to amorphous silicon dioxide.
(Estimated by analogy)
REFERENCE
Professional judgment
DATA QUALITY
No data located.
Estimated based on analogy to
amorphous silicon dioxide and
professional judgment; no
experimental data located.
LOW: Both amorphous and crystalline silicon are estimated to have low potential for neurotoxic effects
based on analogy to a similar compound and professional judgment.
Low potential for neurotoxic effects.
(Estimated by analogy)
Professional judgment
No data located.
Estimated for crystalline and
amorphous silica based on analogy
to a structurally similar chemical
compound and professional
judgment.
HIGH: Based on the weight of evidence, the hazard designation for both amorphous and crystalline silicon
dioxide is High. Extended workplace exposure to amorphous and crystalline silica dust induced silicosis in
humans. Effects on the lungs, such as increased weight, focal interstitial fibrosis, pulmonary inflammation
and/or granuloma, macrophage accumulation, lesions in the bronchi, and hypertrophy/hyperplasia of the
bronchiolar epithelium were observed following inhalation exposures to amorphous and crystalline silica
dust or aerosol at concentrations as low as 0.001 mg/L in rats.
Amorphous and crystalline silicon
dioxide: Silicosis in humans following
extended workplace exposure.
Amorphous silicon dioxide: 27-Month
inhalation study, rabbit. Dyspnea,
cyanosis, shortness of breath,
emphysema, vascular stenosis, alveolar
cell infiltration, sclerosis, granulomatous,
lesions in the liver, spleen, and kidney.
LOAEL: 28 mg/m3 (0.028 mg/L)
Amorphous silicon dioxide: 1-Year
inhalation study, rabbits. Progressive
NIOSH, 1978a;NIOSH, 1978b
EC, 2000a
EC, 2000a
Test substance amorphous silica and
crystalline silica.
Secondary source, test substance
amorphous silica, study details, test
concentrations, exposure protocol,
and test conditions were not
provided. The original study was in
an unpublished report.
Secondary source, test substance
amorphous silica, study details and
4-339
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
functional incapacitation, emphysema,
pulmonary vascular obstruction, blood
pressure changes, mural cellular
infiltration, peribronchiolar cellular
catarrh, perivascular cellular nodules,
ductal stenosis.
LOAEL: <53 mg/m3 (0.053 mg/L)
Amorphous silicon dioxide: 13-Week
inhalation study, rats.
LOAEC: 1 mg/m3 (0.001 mg/L),
increased lung weight, focal interstitial
fibrosis, pulmonary inflammation, and
pulmonary granulomas.
Reuzeletal., 1991
Amorphous silicon dioxide: In a 13-
week inhalation study, Wistar rats
(70/sex/dose) were exposed whole-body
to SiO2 at concentrations of 0, 1.3, 5.9 or
31 mg/m3 6 hours/day, 5 days/week.
Swollen and spotted lungs and enlarged
mediastinal lymph nodes. Increased
collagen content in the lungs (5.9 and 31
mg/m3). Accumulation of alveolar
macrophages and granular material,
cellular debris, polymorphonuclear
leucocytes, increased septal cellularity.
Accumulation of macrophages was seen
in the mediastinal lymph nodes.
Treatment-related microscopic changes in
the nasal region.
NOAEC: 1.3 mg/m3 (0.0013 mg/L)
LOAEC: 5.9 mg/m3 (0.0059 mg/L)
ECHA, 2013
Amorphous silicon dioxide: In a 13-
week inhalation study, Wistar rats
ECHA, 2013
test conditions were not provided.
The original study was in an
unpublished report.
Test substance amorphous silica;
test concentrations and exposure
protocol are unspecified.
Sufficient study details reported in a
secondary source. Comparative
study including Aerosil 200, Aerosil
R 974 (pyrogenic, hydrophobic),
Sipernat 22 S (precipitated,
hydrophilic) as well as quartz
(crystalline silica at a concentration
of 58 mg/m3) as a positive control).
Sufficient study details reported in a
secondary source. Comparative
4-340
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
(70/sex/dose) were exposed whole-body
to SiO2 at concentrations of 0 or 35
mg/m3 6 hours/day, 5 days/ week. Slight
mean increase in relative lung weight.
Swollen and spotted lungs and enlarged
mediastinal lymph nodes. Accumulation
of alveolar macrophages, intra-alveolar
polymorphonuclear leukocytes, and
increased septal cellularity. Treatment-
related microscopic changes in the nasal
region. Slightly increased collagen
content in the lungs at the end of the
exposure period. Changes were nearly all
reversed during the recovery period.
NOAEC: Not established
LOAEC: 35 mg/m3 (0.035 mg/L; only
dose tested)
Amorphous silicon dioxide: In a 13-
week inhalation study, male Fischer 344
rats were exposed whole body to Aerosil
200 dust at a concentration of 0 or 50
mg/m3 for 6 hours/day, 5 days/week.
Quartz (crystalline silica) was used as
positive control. Invasion of neutrophils
and macrophages into alveoli after both
amorphous and crystalline silica
exposure; more pronounced with the
amorphous type after 6.5 weeks but
decreased during post-exposure period.
Fibrosis was present in the alveolar
septae, but subsided during recovery.
NOAEC: Not established
LOAEC: 50 mg/m3 (0.05 mg/L; only
concentration tested)
ECHA, 2013
study including Aerosil 200, Aerosil
R 974 (pyrogenic, hydrophobic),
Sipernat 22 S (precipitated,
hydrophilic) as well as quartz
(crystalline silica at a concentration
of 58 mg/m3) as a positive control.
Sufficient study details reported in a
secondary source. Aerosil 200:
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5).
4-341
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Amorphous silicon dioxide: In 13 and
18 month inhalation studies, male
monkeys (10/group) were exposed whole
body to 15 mg/m3 (total dust, pyrogenic
and precipitated; 15.9 mg/m3 total dust
silica gel; 6.9 - 9.9 mg/m3 (respirable
fraction) for 6 hours/day, 5 days/week.
Histopathological examination of the lung
revealed Incipient fibrosis, inflammatory
response: aggregation of great amounts of
macrophages, physiological impairment
of lung function.
NOAEC: Not established
LOAEC: « 15 mg/m3 (0.015 mg/L)
(nominal; only dose tested) LOAEC
(related to respirable fraction) > 6 < 9
mg/m3 air (analytical)
ECHA, 2013
Sufficient study details reported in a
secondary source. Three silica
subclasses: Cab-O-Sil type
(pyrogenic), named "fume" silica
(Silica F), (CASRN 112945-52-5):
commercial quality; Hi-Sil
(precipitated): silica P (CASRN
112926-00-8) commercial quality;
silica gel: silica G (CASRN 112926-
00-8) commercial quality.
Amorphous silicon dioxide: In a 14-day
inhalation study, Wistar rats
(40/sex/group) were exposed to Aerosil
200 at concentrations of 0, 17, 44 or 164
mg/m3 for 6 hours/day, 5 days/week.
Respiratory distress, increased lung
weight, decreased kidney and liver
weights, dose-dependent changes in lung
characteristics (pale, spotted, spongy,
alveolar interstitial pneumonia, early
granulomata).
NOAEL: Not established
LOAEL: <17 mg/m3 (<0.017 mg/L,
lowest concentration tested)
EC, 2000a; ECHA, 2013
Secondary source, test substance
identified as Aerosil 200: >99.8 %
(SiO2): CAS-Name: Silica,
amorphous, fumed, crystalline-free;
CASRN: 112945-52-5; limited
study details and test conditions
provided. The original study was in
an unpublished report.
Amorphous silicon dioxide: In a 14-day
inhalation study, Wistar rats were
exposed whole body to Sipernat 22S at
EC, 2000a; ECHA, 2013
Sufficient study details reported in a
secondary source. SIPERNAT 22S
>98 %(SiO2): CAS-Name: Silica,
4-342
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
concentrations of 46, 180 or 668 mg/m .
Respiratory distress, increased lung
weight, decreased liver weights, dose-
dependent changes in lung characteristics
(pale, spotted, spongy, alveolar interstitial
pneumonia, early granulomata),
accumulation of alveolar macrophages
and particulate material in lungs.
NOAEC: Not established
LOAEC: <46 mg/m3 (<0.046 mg/L,
lowest concentration tested)
Amorphous silicon dioxide: In a 5-day
inhalation study, male Wistar rats
(10/dose) were exposed whole body to
Syloid 74 at concentrations of 0, 1,5, and
25 mg/m3 for 6 hours/day. Quartz
(crystalline silica) was examined as a
positive control. Significant mean
increase in lung weight, very slight
hypertrophy of the bronchiolar
epithelium, accumulation of alveolar
macrophages accompanied by a few
granulocytes/neutrophils at high dose.
NOAEC: 5.13 mg/m3 (0.00513 mg/L)
LOAEC: 25.1 mg/m3 (0.0251 mg/L)
ECHA, 2013
Amorphous silicon dioxide: In a 5-day
inhalation study, Wistar rats
(10/sex/group) were exposed nose-only to
Zeosil 45 aerosol at concentrations of 0,
1, 5, 25 mg/m3 for 6 hours/day. Slight
increases in lung weights of the high-dose
group, increase in relative weights of
tracheobronchial lymph nodes in females.
Increased absolute numbers of
ECHA, 2013
precipitated, crystalline-free
(CASRN 112926-00-8).
Sufficient study details reported in a
secondary source. Syloid 74, CAS-
Name: Silica gel, crystalline-free
(CASRN 112926-00-8), purity ca.
100%.
Sufficient study details reported in a
secondary source. ZEOSIL 45: CAS
name, Silica, precipitated,
crystalline-free (CASRN 112926-
00-8); impurities: Na (1.9 %), S (0.8
%), Al (0.045 %), Fe (0.02 %), Ca
0.06 %.
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
neutrophils, hypertrophy and hyperplasia
of the bronchiolar epithelium at high
dose.
NOAEC: 5.39 mg/m3 (0.00539 mg/L)
LOAEC: 25.2 mg/m3 (0.0252 mg/L)
Amorphous silicon dioxide: In a 5-day
inhalation study, male Wistar rats
(10/group) were exposed nose-only to
CAB-O-SIL M5 at concentrations of 0,
1.39, 5.41 and 25 mg/m3 for 6 hours/day.
Significant mean increases in relative and
absolute lung weights of the mid- and
high-dose groups. Very slight
hypertrophy of the bronchiolar epithelium
(mid and high dose) and slight
hypertrophy (high dose). Accumulation of
alveolar macrophages accompanied by a
few granulocytes/neutrophils (mid and
high dose). Accumulation of macrophages
accompanied by infiltration of
polymorphonuclear leukocytes (high
dose). Very slight macrophage
accumulation still present following 3
months of recovery (high dose).
NOEC: 1.39 mg/m3 (0.00139 mg/L)
LOAEC: 5.41 mg/m3 (0.00541 mg/L)
ECHA, 2013
Sufficient study details reported in a
secondary source. CAB-O-SIL M5:
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5), purity ca. 100%.
Amorphous silicon dioxide: In a 103
week study, Fischer 344 rats
(40/sex/group) were fed Syloid 44
continuously in the diet at concentrations
of 1.25, 2.5 and 5%. Interim sacrifice of
10/sex after 6 and 12 months. Reduced
liver weight in females after 12 and 24
months is not considered to be treatment-
ECHA, 2013
Sufficient study details reported in a
secondary source. Syloid 244:
Silica, precipitated, crystalline-free
(CASRN 112926-00-8).
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DATA QUALITY
related. There were no other treatment-
related effects.
NOAEL: 5% (~ 2,000 mg/kg bw-day for
average of male and female; highest dose
tested)
LOAEL: Not established
Amorphous silicon dioxide: In a 93
week study, B6C3F1 mice (40/sex/dose)
were fed Syloid 244 continuously in the
diet at concentrations of 0, 1.25, 2.5 or
5%. Interim sacrifice of 10/sex after 6 and
12 months. Transient retardation in body
weight gain was not biologically relevant.
No other adverse treatment-related
effects.
NOAEL: 5% (4,500 or 5,800 mg/kg bw-
day for average of male/female,
respectively; highest dose tested)
LOAEL: Not established
ECHA, 2013
Sufficient study details reported in a
secondary source. Syloid 244:
Silica, precipitated, crystalline-free
(CASRN 112926-00-8).
Amorphous silicon dioxide: In a 6-
month study, Charles River rats
(12/sex/group) were fed Syloid 244 in the
diet daily at doses of 0, 2,170 and 7,950
mg/kg bw-day (males) or 0, 2,420 and
8,980 mg/kg bw-day (females). There
were no treatment-related effects. Isolated
pathological findings were not related to
test substance.
NOAEL: 7,950 mg/kg bw-day (males) or
8,980 mg/kg bw-day (females) (highest
doses tested)
LOAEL: Not established
ECHA, 2013
Sufficient study details reported in a
secondary source. Syloid 244:
Silica, precipitated, crystalline-free
(CASRN 112926-00-8).
Amorphous silicon dioxide: In a 13- ECHA, 2013
Silica, amorphous, fumed,
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
week study, Charles River rats were fed
Cab-O-Sil(fluffy) (>99 % SiO2)
continuously in the diet at concentrations
of 1, 3, and 5% (mean estimated dose:
700, 2,100, and 3,500 mg/kg bw-day). No
clinical signs of toxicity. No gross
pathological or histopathological
treatment-related changes.
NOAEL: 5% (~ 3,500 mg/kg bw-day;
highest dose tested)
LOAEL: Not established
crystalline-free (CASRN 112945-
52-5).
Amorphous silicon dioxide: In a 13-
week dietary study, Wistar rats
(10/sex/dose) were fed SiO2 continuously
in the diet at concentrations of
approximately 0, 0.05, 2 and 6.7% (mean
estimated doses: 300-330, 1,200-1,400,
4,000-4,500 mg/kg-day). Slightly
increased mean food intake at high dose,
with no corresponding body weight gain.
No clinical signs of toxicity or other
findings (hematological, blood-chemical
and urinary parameters). Gross and
microscopic examination did not reveal
any treatment-related changes.
NOAEL: 6.7% (4,000-45,000 mg/kg bw-
day (nominal, highest dose tested)
LOAEL: Not established
ECHA, 2013
Sufficient study details reported in a
secondary source. Silica,
precipitated, crystalline-free
(CASRN 112926-00-8).
Amorphous silicon dioxide: Biogenic
silica fibers induced ornithine
decarboxylase activity of epidermal cells
in mice following topical application.
IARC, 1997
Test substance amorphous silica.
Crystalline silicon dioxide: 2-Year
inhalation (whole body) study, rats
Rice, 2000; OECD SIDS, 2011
Test substance identified as
crystalline silica (DQ-12 quartz,
4-346
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
(50/sex) exposed to air or 1 mg/m3 6
hours/day, 5 days/week). Subpleural and
peribronchial fibrosis, focal
lipoproteinosis cholesterol clefts, enlarged
lymph nodes, granulomatous lesions in
the walls of large bronchi.
LOAEL: 1 mg/m3 (0.001 mg/L; only dose
tested)
containing 74% respirable quartz.
Crystalline silicon dioxide: Silicotic
nodules with reticulin fibrosis was
reported by day 220 and dense, rounded
collagenous nodules were reported on day
300 in rats following inhalation exposure
(18 hours/day, 5 days/week) of 30,000
particles/mL (40% < 0.5 microns) for up
to 420 days.
EC, 2000b
Limited study details reported in a
secondary source.
Crystalline silicon dioxide: 6-Month
inhalation study, rats. Increased collagen
and elastin content in the lungs, induced
type II cell hyperplasia in alveolar
compartment and intralymphatic
microgranulomas around bronchioles.
NOAEL: Not established
LOAEL: 2 mg/m3 (0.002 mg/L)
Rice, 2000
Test substance identified as
crystalline silica (quartz); test
concentrations not specified.
Crystalline silicon dioxide: 13-week
inhalation study in male rats exposed to 0
or 3 mg/m3 (6 hours/day, 5 days/week).
Treated rats presented with pulmonary
inflammation and fibrosis.
NOAEL: Not established
LOAEL: 3 mg/m3 (0.003 mg/L; only dose
tested)
OECDSIDS, 2011
Study details reported in a
secondary source; test substance
identified at cristobalite.
Crystalline silicon dioxide: 4-week
4-347
OECDSIDS, 2011
Study details reported in a
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
inhalation study in female rats exposed to
0, 0.1, 1, or 10 mg/m3 (6 hours/day, 5
days/week). Evaluation of
bronchoalveolar lavage fluid occurred on
weeks 1, 8, and 24 following exposure.
Significantly increased levels of
granulocytes and increased levels of
lactate dehydrogenase and beta-
glucuronidase were reported at 24 weeks
post exposure at a concentration of 1
mg/m3.
NOAEL: 0.1 mg/m3 (0.0001 mg/L)
LOAEL: 1 mg/m3 (0.001 mg/L)
secondary source; test substance
identified at quartz.
Crystalline silicon dioxide: 9-day
inhalation study in mice
Minimal interstitial thickening,
accumulation of mononuclear cells, and
slight lymphoid hypertrophy in the lungs
were reported.
NOAEL: Not established
LOAEL: 10 mg/m3 (0.01 mg/L)
OECDSIDS, 2011
Limited study details reported in a
secondary source; test
concentrations were not specified.
Crystalline silicon dioxide: 3-day
inhalation study in rats exposed to 0, 10,
or 100 mg/m3 of cristobalite (6
hours/day).
Increased granulocytes and other markers
of cytotoxicity from the lung lavage fluid
were reported in all treated animals.
NOAEL: Not established
LOAEL: 10 mg/m3 (0.01 mg/L; lowest
dose tested)
OECDSIDS, 2011
Limited study details reported in a
secondary source; test substance
identified as cristobalite.
14-Day oral dietary study, rats. No
clinical signs or other findings.
EC, 2000a
Secondary source, test substance
unspecified silica, study details and
4-348
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
NOAEL: 24,200 mg/kg-day (highest dose
tested)
LOAEL: Not established
6-Month oral dietary study, rats. No
clinical signs or other findings.
NOAEL: 497 mg/kg-day (highest dose
tested)
LOAEL: Not established
13 -Week oral dietary study, rats. No
clinical signs or other findings.
NOAEL: 8% diet (highest dose tested)
LOAEL: Not established
Up to 1 year inhalation study, rats.
Enlarged and discolored lymph nodes,
perivascular and peribronchiolar dust cell
granuloma, necrotic cells.
NOAEL: Not established
LOAEL: <0.045 mg/L (lowest
concentration tested)
4-Week oral dietary study, dog. No
clinical signs or other findings.
NOAEL 800 mg/kg-day (highest dose
tested)
LOAEL: Not established
In a 3-week dermal study, SiO2 was
applied to the intact and abraded skin of
rabbits (2/sex/group) at doses of 0, 5,000,
10,000 mg/kg bw-day (nominal) for 18
hours/day, 5 days/week. No evidence of
systemic toxicity or of gross or
REFERENCE
EC, 2000a
EC, 2000a
EC, 2000a
EC, 2000a
ECHA, 2013
DATA QUALITY
test conditions were not provided.
The original study was in an
unpublished report.
Secondary source, test substance
unspecified silica, study details and
test conditions were not provided.
The original study was in an
unpublished report.
Secondary source, test substance
unspecified silica, study details and
test conditions were not provided.
The original study was in an
unpublished report.
Secondary source, test substance
unspecified silica, study details and
test conditions were not provided.
The original study was in an
unpublished report.
Secondary source, test substance
unspecified silica, study details and
test conditions were not provided.
The original study was in an
unpublished report.
Unassignable. 21 -Day dermal
exposure study using a prolonged
daily exposure regimen (18 h/d, 5
d/wk) instead of 6 h/d. Test
substance form not specified.
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PROPERTY/ENDPOINT
DATA
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microscopic pathology.
NOAEL: > 10,000 mg/kg bw-day
(highest dose tested)
LOAEL: Not established
Immune System Effects
Amorphous silicon dioxide: In a 12-
month study, male Hartley Guinea pigs
(20/dose) were exposed whole body to
concentrations of 15 mg/m3 (total dust,
pyrogenic and precipitated); 15.9 mg/m3
(total dust silica gel) and 6.9-9.9 mg/m3
(respirable <4.7 (im) for 5.5 - 6 hours/day,
5 days/week. A few macrophages
containing particles of amorphous silica
were observed in the lungs and lymph
nodes.
NOAEC: > 6 < 9 mg/m3 (> 0.006 < 0.009
mg/L)
LOAEC: Not established
ECHA, 2013
Crystalline silicon dioxide: 15- or 27-
week inhalation study in mice exposed to
0 or 5 mg/m3 (6 hours/day, 5 days/week).
Increased spleen weight and formation of
plaque in the spleen was reported.
NOAEL: Not established
LOAEL: 5 mg/m3 (0.005 mg/L; only dose
tested)
OECDSIDS, 2011
Sufficient study details reported in a
secondary source. Three silica
subclasses: Cab-O-Sil type
(pyrogenic), named "fume" silica
(Silica F), (CASRN 112945-52-5):
commercial quality; Hi-Sil
(precipitated): silica P (CASRN
112926-00-8) commercial quality;
silica gel: silica G (CASRN 112926-
00-8) commercial quality.
Study details reported in a
secondary source; test substance
identified as quartz.
4-350
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
Skin Sensitization
Skin Sensitization
Respiratory Sensitization
[Respiratory Sensitization
Eye Irritation
Eye Irritation
DATA
REFERENCE
DATA QUALITY
LOW: Amorphous silicon dioxide was not a dermal sensitizer in guinea pigs or humans.
No experimental data were located for crystalline silicon dioxide. It is estimated that crystalline silicon
dioxide, if present, is not likely to be a skin sensitizer based on analogy to amorphous silicon dioxide and
professional judgment.
Amorphous silicon dioxide: Not
sensitizing in a guinea pig maximization
test.
Amorphous silicon dioxide: Not
sensitizing, humans (occupational
surveys)
Crystalline silicon dioxide: There is low
potential for skin Sensitization based on
analogy to amorphous silicon dioxide.
(Estimated by analogy)
EC, 2000a
ECHA, 2013
Professional judgment
Secondary source, study details and
test conditions were not provided.
The original study was in an
unpublished report.
Not assignable (no further details).
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5) or Silica gel, precipitated,
crystalline-free. (CASRN 112926-
00-8).
Estimated based on analogy to
amorphous silicon dioxide and
professional judgment; no
experimental data located.
No data located.
No data located.
LOW: Amorphous silicon dioxide was not irritating to slightly irritating in rabbits and slightly irritating
in humans. If present, crystalline silicon dioxide would be assigned a Moderate hazard designation based
on a study reporting fibrotic nodules in rabbit eyes.
Amorphous silicon dioxide: Slightly
irritating, rabbits
Amorphous silicon dioxide: Slightly
irritating, humans
Amorphous silicon dioxide: Not
irritating, rabbits (several studies)
EC, 2000a
EC, 2000a
EC, 2000a; ECHA, 2013
Secondary source, study details and
test conditions were not provided.
The original study was in an
unpublished report.
Secondary source, study details and
test conditions were not provided.
The original study was in an
unpublished report.
Sufficient study details reported in a
secondary source. Silica,
precipitated, crystalline-free
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PROPERTY/ENDPOINT
Dermal Irritation
Dermal Irritation
Endocrine Activity
DATA
Crystalline silicon dioxide: Quartz was
reported to cause fibrotic nodules in
rabbit eyes.
REFERENCE
EC, 2000b
DATA QUALITY
(CASRN 112926-00-8) or Silica,
amorphous, fumed, crystalline-free
(CASRN 112945-52-5).
Limited study details reported in a
secondary source; the severity and
duration of the irritation was not
specified. Irritation may be a result
of mechanical mechanisms and
scratching of the eye.
VERY LOW: Amorphous silicon dioxide was not irritating to the skin of rabbits or humans.
No experimental data was located for crystalline silicon dioxide for this endpoint. It is estimated that
crystalline silicon dioxide, if present, is not likely to be a skin irritant based on analogy to amorphous
silicon dioxide and professional judgment.
Amorphous silicon dioxide: Not
irritating, rabbits (several studies)
Amorphous silicon dioxide: Not
irritating, humans
Crystalline silicon dioxide: There is low
potential for skin irritation based on
analogy to amorphous silicon dioxide.
(Estimated by analogy)
EC, 2000a;ECHA, 2013
EC, 2000a
Professional judgment
Sufficient study details reported in a
secondary source. Silica,
precipitated, crystalline-free (CAS-
No. 112926-00-8) or Silica,
amorphous, fumed, crystalline-free
(CAS-No. 112945-52-5).
Secondary source, study details and
test conditions were not provided.
The original study was in an
unpublished report.
Estimated based on analogy to
amorphous silicon dioxide and
professional judgment; no
experimental data located.
No data located.
No data located.
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Immunotoxicity
Subjects that develop silicosis following exposure to crystalline silica have increased numbers of
macrophages in the lungs. Effects on the lungs, such as inflammatory response, accumulation of alveolar
macrophages, and infiltration of polymorphonuclear leukocytes were observed following inhalation
exposures to amorphous and crystalline silica dust or aerosols in experimental animals.
Immune System Effects
Amorphous silicon dioxide: In a 5-day
inhalation study, male Wistar rats
(10/group) were exposed nose-only to
CAB-O-SIL M5 at concentrations of 0,
1.39, 5.41 and 25 mg/m3 for 6 hours/day.
Accumulation of alveolar macrophages
accompanied by a few
granulocytes/neutrophils (mid and high
dose). Accumulation of macrophages
accompanied by infiltration of
polymorphonuclear leukocytes (high
dose). Very slight macrophage
accumulation still present following 3
months of recovery (high dose).
NOAEC: 1.39 mg/m3 (0.00139 mg/L)
LOAEC: 5.41 mg/m3 (0.00541 mg/L)
Amorphous silicon dioxide: In a 13-
week inhalation study, male Fischer 344
rats were exposed whole body to Aerosil
200 dust at a concentration of 0 or 50
mg/m3 for 6 hours/day, 5 days/week.
Quartz (crystalline silica) was used as
positive control. Invasion of neutrophils
and macrophages into alveoli after both
amorphous and crystalline silica
exposure; it was more pronounced with
the amorphous type after 6.5 weeks but
decreased during post-exposure period.
Fibrosis was present in the alveolar
septae, but subsided during recovery.
ECHA, 2013
ECHA, 2013
Sufficient study details reported in a
secondary source. CAB-O-SIL M5:
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5), purity ca. 100%.
Sufficient study details reported in a
secondary source. Aerosil 200:
Silica, amorphous, fumed,
crystalline-free (CASRN 112945-
52-5).
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PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
NOAEC: Not established
LOAEC: 50 mg/m3 (0.05 mg/L; lowest
concentration tested)
Amorphous silicon dioxide: In a 13-
week inhalation study, Wistar rats
(70/sex/dose) were exposed whole-body
to SiO2 at concentrations of 0, 1.3, 5.9 or
31 mg/m3 6 hours/day, 5 days/week.
Swollen and spotted lungs and enlarged
mediastinal lymph nodes. Accumulation
of alveolar macrophages and granular
material, cellular debris,
polymorphonuclear leucocytes, increased
septal cellularity. Accumulation of
macrophages was seen in the mediastinal
lymph nodes. Treatment-related
microscopic changes in the nasal region.
NOAEC: 1.3 mg/m3 (0.0013 mg/L)
LOAEC: 5.9 mg/m3 (0.0059 mg/L)
ECHA, 2013
Amorphous silicon dioxide: In a 13-
week inhalation study, Wistar rats
(70/sex/dose) were exposed whole-body
to SiO2 at concentrations of 0 or 35
mg/m3 6 hours/day, 5 days/ week.
Swollen and spotted lungs and enlarged
mediastinal lymph nodes. Accumulation
of alveolar macrophages, intra-alveolar
polymorphonuclear leukocytes, and
increased septal cellularity.
NOAEC: Not established
LOAEC: 35 mg/m3 (0.035 mg/L; lowest
concentration tested)
ECHA, 2013
Sufficient study details reported in a
secondary source. Comparative
study including Aerosil 200, Aerosil
R 974 (pyrogenic, hydrophobic),
Sipernat 22 S (precipitated,
hydrophilic) as well as quartz
(crystalline silica at a concentration
f ^ & / ^ was used as a positive control).
Sufficient study details reported in a
secondary source. Comparative
study including Aerosil 200, Aerosil
R 974 (pyrogenic, hydrophobic),
Sipernat 22 S (precipitated,
hydrophilic) as well as quartz
(crystalline silica at a concentration
of 58 mg/m3 was used as a positive
control).
Amorphous silicon dioxide: In a 14-Day
inhalation study, Wistar rats were
EC, 2000a; ECHA, 2013
Sufficient study details reported in a
secondary source. SIPERNAT 22S
4-354
-------
Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
exposed whole body to Sipernat 22S at
concentrations of 46, 180 or 668 mg/m3.
Dose-dependent changes in lung
characteristics (pale, spotted, spongy,
alveolar interstitial pneumonia, early
granulomata), accumulation of alveolar
macrophages and particulate material in
lungs.
NOAEC: Not established
LOAEC: <46 mg/m3 (<0.046 mg/L;
lowest concentration tested)
Amorphous silicon dioxide: In a 12-
month study, male Hartley Guinea pigs
(20/dose) were exposed whole body to
concentrations of 15 mg/m3 (total dust,
pyrogenic and precipitated); 15.9 mg/m3
(total dust silica gel) and 6.9-9.9 mg/m3
(respirable <4.7 (im) for 5.5 - 6 hours/day,
5 days/week. A few macrophages
containing particles of amorphous silica
were observed in the lungs and lymph
nodes.
NOAEC: > 6 < 9 mg/m3 (> 0.006 < 0.009
mg/L)
LOAEC: Not established
ECHA, 2013
Amorphous silicon dioxide: In 13 and
18 month inhalation studies, male
monkeys (10/group) were exposed whole
body to 15 mg/m3 (total dust, pyrogenic
and precipitated); 15.9 mg/m3 (total dust
silica gel); and 6.9 - 9.9 mg/m3 (respirable
<4.7 (im) for 6 hours/day, 5 days/week.
Inflammatory response: aggregation of
great amounts of macrophages,
ECHA, 2013
>98 %(SiO2): CAS-Name: Silica,
precipitated, crystalline-free
(CASRN 112926-00-8).
Sufficient study details reported in a
secondary source. Three silica
subclasses: Cab-O-Sil type
(pyrogenic), named "fume" silica
(Silica F), (CASRN 112945-52-5):
commercial quality; Hi-Sil
(precipitated): silica P (CASRN
112926-00-8) commercial quality;
silica gel: silica G (CASRN 112926-
00-8) commercial quality.
Sufficient study details reported in a
secondary source. Three silica
subclasses: Cab-O-Sil type
(pyrogenic), named "fume" silica
(Silica F), (CASRN 112945-52-5):
commercial quality; Hi-Sil
(precipitated): silica P (CASRN
112926-00-8) commercial quality;
silica gel: silica G (CASRN 112926-
4-355
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
physiological impairment of lung
function.
NOAEC: Not established
LOAEC: ca. 15 mg/m3 (0.015 mg/L)
(nominal, lowest concentration tested)
00-8) commercial quality.
Crystalline silicon dioxide: Human
subjects with silicosis have increased
macrophages and lymphocytes in the
lungs, but minimal increases in
neutrophils.
IARC, 1997
Test substance crystalline silica.
Crystalline silicon dioxide: Exposure of
rats to high concentrations of quartz leads
to recruitment of neutrophils, marked
persistent inflammation, and proliferative
responses of the epithelium.
IARC, 1997
Test substance crystalline silica.
Crystalline silicon dioxide: In vitro
studies show that crystalline silica can
stimulate the release of cytokines and
growth factors from macrophages and
epithelial cells; some evidence exists that
these effects occur in vivo (species not
specified).
IARC, 1997
Test substance crystalline silica.
Crystalline silicon dioxide: Crystalline
silica results in inflammatory cell
recruitment in a dose-dependent manner
(species not specified).
IARC, 1997
Test substance crystalline silica.
Crystalline silicon dioxide: Crystalline
silica deposited in the lungs causes
macrophage injury and activation (species
not stated).
IARC, 1997
Test substance crystalline silica.
Crystalline silicon dioxide: 15- or 27-
week inhalation study in mice exposed to
0 or 5 mg/m3 (6 hours/day, 5 days/week).
Increased spleen weight and formation of
OECDSIDS, 2011
Study details reported in a
secondary source; test substance
identified as quartz.
4-356
-------
Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
plaque in the spleen was reported.
NOAEL: Not established
LOAEL: 5 mg/m3 (0.005 mg/L; only dose
tested)
REFERENCE
DATA QUALITY
ECOTOXICITY
ECOSAR Class
Acute Aquatic Toxicity
Fish LC50
Not applicable
LOW: Amorphous silicon dioxide experimental LC50 and EC50 values for fish, daphnia and green algae
are all >100 mg/L. The large MW, limited bioavailability and low water solubility suggest there will be no
effects at saturation (NES). It is estimated by professional judgment that crystalline forms of silicon
dioxide will also have low acute aquatic toxicity based on analogy to amorphous silicon dioxide. For some
organisms in marine habitats, silica and silicates are used as nutrients; they are used for building some cell
walls, skeletal structures or shells.
Amorphous silicon dioxide: Freshwater
fish Brachydanio rerio 96-hour LC50 =
5,000 mg/L
(Experimental)
Amorphous silicon dioxide: Freshwater
fish Brachydanio rerio 96-hour LC50
> 10,000 mg/L;
static test conditions; nominal
concentrations: 1,000 and 10,000 mg/L
(Experimental)
Amorphous and crystalline silicon
dioxide: Freshwater fish LC50 >100 mg/L
(Estimated)
EC, 2000a
ECHA, 2013
Professional judgment
Secondary source; test substance
form, study details and test
conditions were not provided.
Sufficient study details reported in a
secondary source. GLP guideline
study. Data are for amorphous silica.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES.
For some organisms in marine
habitats, silica and silicates are used
as nutrients; they are used for
building some cell walls, skeletal
structures or shells.
4-357
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Daphnid LC50
Amorphous silicon dioxide: Daphnia
magna 24-hour effect level based on
mobility EL50 > 10,000 mg/L
(Experimental)
ECHA, 2013
Amorphous silicon dioxide:
Ceriodaphnia dubia EC50 ~ 7,600 mg/L
(Experimental)
EC, 2000a
Amorphous and crystalline silicon
dioxide: Daphnia magna LC50 >100
mg/L
(Estimated)
Professional judgment
Sufficient study details reported in a
secondary source. Guideline study
with acceptable restrictions (24 h
instead of 48 h). Data are for Silica,
amorphous.
Secondary source; test substance
form, study details and test
conditions were not provided. The
original study was in an unpublished
report.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES.
For some organisms in marine
habitats, silica and silicates are used
as nutrients; they are used for
building some cell walls, skeletal
structures or shells.
Green Algae EC s
Amorphous silicon dioxide: Green algae
Selenastrum capricornutum EC50 = 440
mg/L
(Experimental)
EC, 2000a
Amorphous and crystalline silicon
dioxide: Green algae EC50 >100 mg/L
(Estimated)
Professional judgment
Secondary source; test substance
form, study details and test
conditions were not provided. The
original study was in an unpublished
report.
The large MW, limited
bioavailability and low water
solubility suggest there will be NES.
For some organisms in marine
habitats, silica and silicates are used
as nutrients; they are used for
building some cell walls, skeletal
structures or shells.
4-358
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
Chronic Aquatic Toxicity
LOW: No experimental chronic data were located. The large MW, limited bioavailability and low water
solubility suggest there will be no effects at saturation (NES). It is estimated by professional judgment that
crystalline forms of silicon dioxide will also have low chronic aquatic toxicity based on large MW, limited
bioavailability and low water solubility suggesting there will be no effects at saturation (NES). For some
organisms in marine habitats, silica and silicates are used as nutrients; they are used for building some cell
walls, skeletal structures or shells.
Fish ChV
Amorphous and crystalline silicon
dioxide: Freshwater fish ChV >10 mg/L
(Estimated)
Professional judgment
The large MW, limited
bioavailability and low water
solubility suggest there will be NES.
For some organisms in marine
habitats, silica and silicates are used
as nutrients; they are used for
building some cell walls, skeletal
structures or shells.
Daphnid ChV
Amorphous and crystalline silicon
dioxide: Daphnia magna ChV >10 mg/L
(Estimated)
Professional judgment
The large MW, limited
bioavailability and low water
solubility suggest there will be NES.
For some organisms in marine
habitats, silica and silicates are used
as nutrients; they are used for
building some cell walls, skeletal
structures or shells.
Green Algae ChV
Amorphous and crystalline silicon
dioxide: Green algae ChV >10 mg/L
(Estimated)
Professional judgment
The large MW, limited
bioavailability and low water
solubility suggest there will be NES.
For some organisms in marine
habitats, silica and silicates are used
as nutrients; they are used for
building some cell walls, skeletal
structures or shells.
ENVIRONMENTAL FATE
4-359
-------
Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
Transport
Henry's Law Constant (atm-
m3/mole)
Sediment/Soil
Adsorption/Desorption - Koc
Level III Fugacity Model
Persistence
Water
Soil
Aerobic Biodegradation
Volatilization Half-life for
Model River
Volatilization Half-life for
Model Lake
Aerobic Biodegradation
Anaerobic Biodegradation
DATA
REFERENCE
DATA QUALITY
Silicon dioxide is a component of sand, soil, and sediment. Silicon dioxide has low water solubility and as a
solid, it is expected to have a negligible estimated vapor pressure; these two factors correspond to an
expected low Henry's Law constant. Amorphous forms of silicon dioxide will be relatively immobile in the
environment with the exception of silicon dioxide dust in the atmosphere. Crystalline forms of silicon
dioxide are expected to behave similarly in the environment and be relatively immobile with the exception
of dust particulates.
Amorphous and crystalline silicon
dioxide: <10~8 (Estimated)
Amorphous and crystalline silicon
dioxide: Not applicable (Estimated)
Professional judgment
Professional judgment
Cutoff value for nonvolatile
compounds based on professional
judgment. This substance contains
inorganic compounds that are
outside the estimation domain of
EPI.
As a component of sand, soil, and
sediment, the soil-water partition
coefficient is not applicable for
silicon dioxide.
No data located.
HIGH: Amorphous silicon dioxide is expected to have high persistence in the environment because silicon
dioxide is a recalcitrant, fully oxidized, inorganic substance and therefore will not biodegrade, oxidize in
air, or undergo hydrolysis under environmental conditions. Silicon dioxide does not absorb light at
environmentally relevant wavelengths and is not expected to photolyze. No degradation processes for
silicon dioxide, under typical environmental conditions, were identified. It is also estimated that in the
environment crystalline forms of silicon dioxide will behave similarly and have high persistence based on
professional judgment.
Amorphous and crystalline silicon
dioxide: Recalcitrant (Estimated)
>1 year for both amorphous and
crystalline silicon dioxide (Estimated)
>1 year for both amorphous and
crystalline silicon dioxide (Estimated)
Amorphous and crystalline silicon
dioxide: Recalcitrant (Estimated)
Professional judgment; OECD
SIDS, 2004a
Professional judgment
Professional judgment
Professional judgment
No data located.
4-360
-------
Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
Air
Reactivity
Soil Biodegradation with
Product Identification
Sediment/Water
Biodegradation
Atmospheric Half-life
Photolysis
Hydrolysis
Environmental Half-life
Bioaccumulation
Fish BCF
Other BCF
DATA
Amorphous and crystalline silicon
dioxide: >1 year (Estimated)
Amorphous and crystalline silicon
dioxide: Not a significant fate process
(Estimated)
Amorphous and crystalline silicon
dioxide: >1 year (Estimated)
REFERENCE
Professional judgment
Professional judgment
Professional judgment
DATA QUALITY
No data located.
No data located.
Silicon dioxide does not absorb UV
light at environmentally relevant
wavelengths and is not expected to
undergo photolysis.
Silicon dioxide is a fully oxidized,
insoluble, inorganic material and is
not expected to undergo hydrolysis.
Not all input parameters for this
model were available to run the
estimation software (EPI). This
substance contains inorganic
compounds that are outside the
estimation domain of EPI.
LOW: Amorphous silicon dioxide is not expected to bioaccumulate based on professional judgment. Also
based on professional judgment crystalline forms of silicon dioxide are not expected to bioaccumulate.
Although for some organisms in marine habitats, silica and silicates are used as nutrients. They are used
for building some cell walls, skeletal structures or shells.
Amorphous and crystalline silicon
dioxide: <100 (Estimated)
For some organisms in marine habitats,
silica and silicates are used as nutrients;
they are used for building skeletal
structures or shells. For example, diatoms
absorb soluble silica from water and
metabolize it for an external skeleton.
Professional judgment
EC, 2000b; OECD SIDS, 2004a;
HSDB, 2009
This inorganic compound is not
amenable to available estimation
methods.
Supporting information about the
bioaccumulation of this compound
in marine environments. Some
organisms in marine habitats use
silica and silicates as nutrients; they
are used for building some cell
walls, skeletal structures or shells.
4-361
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Silicon dioxide (amorphous) CASRN 7631-86-9
PROPERTY/ENDPOINT
DATA
REFERENCE
DATA QUALITY
BAF
Amorphous and crystalline silicon
dioxide: <100 (Estimated)
Professional judgment
This inorganic compound is not
amenable to available estimation
methods.
Metabolism in Fish
No data located.
ENVIRONMENTAL MONITORING AND BIOMONITORING
Environmental Monitoring
Silicon dioxide is a ubiquitous mineral that occurs naturally in the environment as sand and quartz (HSDB,
2009).
Ecological Biomonitoring
No data located.
Human Biomonitoring
No data located.
4-362
-------
Alexander GB, Heston WM, Her RK (1954) J Phys Chem 58:453-455.
Daubert TE and Banner RP (1989) Physical and thermodynamic properties of pure chemicals data compilation. Washington, DC: Taylor and
Francis.
EC (2000a) Dataset for silicon dioxide, chemically prepared. European Commission, European Chemicals Bureau.
EC (2000b) [Quartz (SiO2)]. IUCLID Dataset. European Commission. European Chemicals Bureau.
http://esis.jrc.ec.europa.eu/doc/IUCLID/data_sheets/14808607.pdf
ECHA (2013) Silicon dioxide. Registered substances. http://apps.echa.europa.eu/registered/data/dossiers/DISS-76fd35eO-69c4-29a3-e044-
00144f26965e/DISS-76fd35eO-69c4-29a3 -e044-00144f26965e_DISS-76fd35eO-69c4-29a3-e044-00144f26965e.html.
EPA (2010) TSCA new chemicals program (NCP) chemical categories. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/oppt/newchems/pubs/npcchemicalcategories.pdf.
ESIS (2012) European chemical Substances Information System. European Commission, http://esis.jrc.ec.europa.eu/.
Florke OW, Graetsch H, Brunk F, et al. (2000) Silica. Ullmann's Encyclopedia of Industrial Chemistry.
HSDB (2009) Amorphous silica. Hazardous Substances Data Bank. http://toxnet.nlm.gOv/cgi-bin/sis/search/f7.temp/~qZ735z:l:FULL.
IARC (1987) Silica. IARC Monogr Eval Carcinog Risk Chem Hum 42 International Agency for Research on Cancer.:39-143.
IARC (1997) SILICA: Crystalline silica - inhaled in the form of quartz or cristobalite from occupational sources (Group 1): Amorphous silica
(Group 3). IARC monographs on the evaluation of carcinogenic risks to humans summaries and evaluations.68 International Agency for Research
on Cancer, World Health Organization, http://www.inchem.org/documents/iarc/vol68/silica.html.
KEMI (2006) Silicon dioxide. Information on substances. KEMI Swedish Chemicals Agency.
http://apps.kemi.se/flodessok/floden/kemamne_eng/kiseldioxid_eng .htm.
Lewis RJ (1999) Sax's dangerous properties of industrial materials. 10th ed. New York, NY: John Wiley & Sons, Inc.
Lide DR (2000) 2000-2001 CRC handbook of chemistry and physics. 81st ed. Boca Raton, FL: CRC Press.
Merck (1996) Merck index. 12th ed. Whitehouse Station, NJ: Merck & Co. Inc.
NIOSH (1978a) Occupational health guideline for amorphous silica.
4-363
-------
NIOSH (1978b) Occupational health guideline for crystalline silica. National Institute of Occupational Safety and Health.
OECD SIDS (2004a) SIDS initial assessment profile silicon dioxide. Organisation for Economic Cooperation and Development. Screening
Information Data Set.
OECD SIDS (2004b) SIDS initial assessment profile synthetic amorphous silica and silicates. Organisation for Economic Cooperation and
Development. Screening Information Data Set.
OECD SIDS (2011) [Quartz and cristobalite]. Initial targeted assessment profile (human health). Organisation for Economic Cooperation and
Development Screening Information Data Set. http://webnet.oecd.org/Hpv/UI/handler.axd?id=b68bb357-e6dd-4db9-b05c-8148223fcOff.
OncoLogic (2008) Version 7.0. U.S. Environmental Protection Agency and LogiChem, Inc.
Reuzel PGJ, Bruijntjes JP, Feron VJ, et al. (1991) Subchronic inhalation toxicity of amorphous silicas and quartz dust in rats. Food Chem Toxicol
29(5):34-354.
Rice F (2000) Concise International Chemical Assessment Document (CICAD) - Crystalline Silica, Quartz. No. 24. United Nations Environment
Programme; International Labour Organization; World Health Organization, http://www.who.int/ipcs/publications/cicad/en/cicad24.pdf.
Waddell W (2013) Silica, amorphous. Kirk-Othmer encyclopedia of chemical technology. John Wiley & Sons.
4-364
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5 Potential Exposure to Flame Retardants and Other Life-
Cycle Considerations
Many factors must be considered to evaluate the risk to human health and the environment posed
by any flame-retardant chemical. Risk is a function of two parameters, hazard and exposure. The
hazard associated with a particular substance or chemical is its potential to impair human health,
safety, or ecological health. While some degree of hazard can be assigned to most substances, the
toxicity and harmful effects of other substances are not fully understood. The exposure potential
of a given substance is a function of the exposure route (inhalation, ingestion, and dermal), the
concentration of the substance in the contact media, and the frequency and duration of the
exposure.
The purpose of this chapter is to identify the highest priority routes of exposure to flame-
retardant chemicals used in printed circuit boards (PCBs). Section 5.1 through Section 5.4
provide general background regarding potential exposure pathways that can occur during
different life-cycle stages, discuss factors that affect exposure potential in an industrial setting,
provide process descriptions for the industrial operations involved in the PCB manufacturing
supply chain (identifying the potential primary release points and exposure pathways), and
discuss potential consumer and environmental exposures. Following this general discussion,
Section 5.5 highlights life-cycle considerations for the ten flame retardants evaluated by this
partnership. The chapter is intended to help the reader identify and characterize the exposure
potential of flame-retardant chemicals based on factors including physical and chemical
properties and reactive versus additive incorporation into the epoxy resin. The information
presented in this chapter should be considered with the chemical-specific hazard assesment
presented in Chapter 4.
Exposure can occur at many points in the life cycle of a flame-retardant chemical. There is a
potential for occupational exposures during industrial operations; exposure to consumers while
the flame-retardant product is being used; and exposure to the general population and
environment when releases occur from product disposal or end-of-life recycling. Figure 5-1
presents a simplified life cycle for a flame-retardant chemical used in a PCB, and Table 5-1
summarizes the potential exposure routes that can occur during each of these life-cycle stages.
The remaining sections of Chapter 5 discuss the information summarized in Figure 5-1 and Table
5-1 in more detail.
5-1
-------
Figure 5-1. Life Cycle of Flame-Retardant Chemicals in PCBs (example with Tetrabromobisphenol A
(TBBPA) as reactive FR)
TBBPA, Bisphenol-A,
Epichlorohydrin, and
Other Chemicals
Laminate Producer
Use of Electronics
Disposal of Electronics to:
Recycling
Incinerator Facility with
Controls
Recycling
Facility without
Controls
Shipping of
Laminate
Electronics Store
Landfi" Disassembly
and Smelting.
Shipping of Electronics
Original Equipment
Manufacturer
Printed Circuit Board (PCS)
Manufacturer
Shipping of PCB
5-2
-------
Table 5-1. Potential Exposure to Flame-Retardant Chemicals throughout Their Life Cycle in PCBs
Life Cycle Stage Potential Exposure
Reactive Flame Retardants
Manufacture: Chemical
manufacture, resin
formulation
Pre-impregnated
material (prepreg) and
laminate production
PCB manufacturing and
assembly
Use
End of Life
Manufacture emissions will vary based on manufacturing practices and physical/chemical
properties; direct exposure is possible because the neat chemical is handled.
Cutting of material can release minor amounts of dust that contains epoxy resin. Reactive flame
retardants are part of the polymer (chemically bound), and only trace amounts of unreacted flame
retardant are anticipated to remain in the polymer matrix. Trace quantities are currently
unknown* and/or will vary based on manufacturing methods and processes.
Remaining, unreacted flame retardant may offgas; PCB manufacturing processes, such as drilling,
edging, and routing, cut into the base material. In electronic assembly, some soldering processes
could induce thermal stress on resins, which could yield degradation products. Testing is needed
to determine the potential for formation of these products.
Only residual unreacted flame retardant is available to offgas during use. In order for exposure to
occur, offgassing from residual unreacted flame retardant would have to escape product casing.
Testing is needed to determine exposure potential.
Disassembly/Recycling: Disassembling electronics and shredding PCBs can release dust that
contains epoxy resin. Reactive flame retardants are chemically bound to the polymer; however,
levels of exposure and any subsequent effects of exposure to the reacted flame retardant products
during the disposal phase of the life cycle, in which flame retardants may become mobilized
through direct intervention processes, such as shredding, are unknown.
Landfill: Testing needs to be conducted to determine exposure potential from leaching from PCBs.
Incineration: Combustion by-products need to be considered (see combustion experiments).
Open Burning: Combustion by-products need to be considered (see combustion experiments).
Smelting: Combustion by-products need to be considered.
Additive Flame Retardants
Manufacture: Chemical
manufacture, resin
formulation
Prepreg and laminate
production
PCB manufacturing and
assembly
Use
End of Life
Manufacture emissions will vary based on manufacturing practices and physical/chemical
properties; direct exposure is possible because the neat chemical is handled.
Cutting of material can release minor amounts of dust that contains epoxy resin. Additive flame
retardants are not chemically bound to the polymer, and their potential to offgas or leach out of
the product is not known. Physical/chemical properties, such as vapor pressure and water
solubility, may contribute to the potential for exposure to these chemicals.
Additive flame retardant may offgas; PCB processes, such as drilling, edging, and routing, cut into
the base material. In electronic assembly, reflow or wave soldering processes could induce
thermal stress on resins, which could yield offgas products. Physical/chemical properties, such as
vapor pressure and water solubility, may contribute to the potential for exposure to these
chemicals.
Although flame retardants are embedded in the polymer matrix, testing needs to be conducted to
better understand the offgassing potential of additive flame retardants. Dermal exposure is not
anticipated since the flame retardants are embedded in the polymer matrix.
Disassembly/Recycling: Disassembling electronics and shredding PCBs can release dust that
contains epoxy resin. Additive flame retardants are not chemically bound to the polymer and can
be released through the dust. Physical/chemical properties, such as vapor pressure, may contribute
to the potential for exposure to these chemicals.
Landfill: Testing needs to be conducted to determine exposure potential from leaching from PCBs.
Incineration: Combustion by-products need to be considered (see combustion experiments).
Open Burning: Combustion by-products need to be considered (see combustion experiments).
Smelting: Combustion by-products need to be considered.
*For TBBPA, Sellstrom and Jansen (1995) found about 0.7 micrograms of residual (or "free") TBBPA per
gram of PCB.
5-3
-------
5.1 Potential Exposure Pathways and Routes (General)
The risk associated with a given chemical or substance is largely dependent on how the exposure
potentially occurs. For example, the toxicological effects associated with inhaling the chemical
are different from those associated with ingesting the chemical through food or water. As a
result, exposure is typically characterized by different pathways and routes.
An exposure pathway is the physical course a chemical takes from the source of release to the
organism that is exposed. The exposure route is how the chemical gets inside the organism. The
three primary routes of exposure are inhalation, dermal absorption, and ingestion. Depending on
the hazard of the chemical, exposure from only one or perhaps all three routes may result in risk.
Expected environmental releases and potential exposure routes of chemicals are dependent upon
their physical and chemical properties. For example, a highly volatile liquid can readily
evaporate from mix tanks, potentially resulting in fugitive air releases and potential exposures to
workers who breathe the vapors, while chemicals manufactured as solids may expose workers to
fugitive dust that may be generated, but are unlikely to generate vapors. Each potential exposure
route, along with appropriate endpoints, should be evaluated independently. Endpoints are the
specific toxicological effect, such as cancer, reproductive harm, or organ/tissue damage. There
are circumstances when a chemical has serious effects for a given endpoint, but due to physical
and chemical properties as well as environmental fate, there is minimal potential for the chemical
to be transported from the release point to the endpoint. This may essentially eliminate the
potential pathway and route of exposure and, therefore, eliminate the associated risk.
Table 5-2 highlights key physical, chemical, and fate properties that affect the likelihood for
exposure to occur: the physical state of the chemical, vapor pressure, water solubility, log Kow,
bioaccumulation potential, and persistence. The relevance of each physical, chemical, and fate
property, as well as its impact on exposure potential, is summarized in Table 5-2. Detailed
descriptions of these properties and how they can be used to assess potential environmental
release, exposure, and partitioning, as well as insight into a chemical's likelihood to cause
adverse toxicological effects, can be found in Chapter 4. More detailed information on physical,
chemical, and fate properties of each flame-retardant chemical can be found in the full chemical
hazard profiles in Section 4.9.
5-4
-------
Table 5-2. Key Physical/Chemical and Fate Properties of Flame-Retardant Chemicals
Physical State of Chemical (ambient conditions)
Relevance to exposure: Indicates if a chemical substance is a solid, liquid, or gas under ambient conditions. This is determined from the melting and boiling points. Chemicals
with a melting point more than 25°C are considered solid. Those with a melting point less than 25°C and a boiling point more than 25°C are considered liquid and those with a
boiling point less than 25°C are considered a gas. Physical state influences potential for dermal and inhalation exposure. For chemicals that exist as a gas, there is generally a
potential for direct inhalation but not dermal exposure. For solids, there is potential for the inhalation and ingestion of dust particles and dermal contact. For liquids, there is
potential for direct dermal contact but not for direct inhalation of the liquid (except in operations that produce aerosols).
TBBPA
Solid
D.E.R. 500
Series
Solid
DOPO
Solid
DowXZ-
92547
Solid
Fyrol PMP
Solid
Aluminum
Hydroxide
Solid
Aluminum
Diethylphos-
phinate
Solid
Melamine
Polyphosphate
Solid
Silicon
Dioxide
(amorphous)
Solid
Magnesium
Hydroxide
Solid
Vapor Pressure (mm Hg) at 25°C
Relevance to exposure: Indicates the potential for a chemical to volatilize into the atmosphere. If a chemical has a vapor pressure leading to volatilization at room temperature or
typical environmental conditions, then the chemical may evaporate and present the potential for inhalation of the gas or vapor. For a Design for the Environment (DIE) chemical
alternatives assessment, inhalation exposure is assumed to occur if the vapor pressure is greater than 1 x 10"8 mmHg. A default value of <10"8 was assigned for chemicals without
data that are anticipated to be nonvolatile this is based on EPA HPV assessment guidance (U.S. EPA 1999).
TBBPA
4.7xlO'8
D.E.R. 500
Series
<10-8b,c
DOPO
2.2xlO-5a
DowXZ-
92547
<10-8b,c
Fyrol PMP
<10-8b,c
Aluminum
Hydroxide
<10'8c
Aluminum
Diethylphos-
phinate
<10'8c
Melamine
Polyphosphate
<1Q-8d
Silicon
Dioxide
(amorphous)
<1Q-8d
Magnesium
Hydroxide
<10'8c
' Extrapolated. Estimated based on polymer assessment literature (Boethling and Nabholz, 1997). ° Estimated based on HPV guidance for nonvolatile compounds. Estimated.
Water Solubility (mg/L)
Relevance to exposure: Indicates the potential of a chemical to dissolve in water and form an aqueous solution. Water soluble chemicals present a higher potential for human
exposure through the ingestion of contaminated drinking water (including well water). In general, absorption after oral ingestion of a chemical with a water solubility less than
10"3 mg/L is not expected. Water soluble chemicals are more likely to be transported into groundwater, absorbed through the gastrointestinal tract or lungs, partition to aquatic
compartments, and undergo atmospheric removal by rain washout. A water solubility of 10"3 mg/L is used for large, high molecular weight (MW) non-ionic polymers according
to the literature concerning polymer assessment (Boethling and Nabholz, 1997). A substance with water solubility at or below 10"3 mg/L is considered insoluble.
TBBPA
4.16
D.E.R. 500
Series
<0.001a'b'c
DOPO
3,574e
DowXZ-
92547
<0.62d
0.001°
Fyrol PMP
8.4 (n=l)b
0.1 (n=2)b
0.001 (n>3)a'b'c
Aluminum
Hydroxide
0.09 at 20 °C,
pH6-7
Aluminum
Diethylphos-
phinate
2.5xl03
Melamine
Polyphosphate
2.0xl04
Silicon
Dioxide
(amorphous)
120
Magnesium
Hydroxide
1.78at20°C,
pH8.3
a Estimated based on EPA High Production Volume assessment guidance. Estimated. ° Estimated based on polymer assessment literature (Boethling and Nabholz, 1997).
Estimated based on proprietary components with MW < 1,000.e Measured value for the hydrolysis product of DOPO.
5-5
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Table 5-2. Key Physical/Chemical and Fate Properties of Flame-Retardant Chemicals (Continued)
Log Kow
Relevance to exposure: Indicates a chemical's tendency to partition between water and lipids in biological organisms. A high log Kow value indicates that the chemical is more
soluble in octanol (lipophilic) than in water, while a low log Kow value means that the chemical is more soluble in water than in octanol. Log Kow can be used to evaluate
absorption and distribution in biological organisms, potential aquatic exposure, and potential general population exposure via ingestion. Generally, chemicals with a log Kow <4
are water soluble and bioavailable, chemicals with a log Kow >4 tend to bioaccumulate. Chemicals with a high log Kow also tend to bind strongly to soil and sediment. Log Kow
cannot be measured for inorganic substances, polymers, and other materials that are not soluble in either water or octanol. This is indicated in the table with "No data".
TBBPA
4.54
D.E.R. 500
Series
7.4 (n=0)a
ll(n=l)a
No data (n>2)
DOPO
1.87a
DowXZ-
92547
3.7-7b
Fyrol PMP
3.4 (n=l)a
4.4 (n=2)a
5.3 (n=3)a
6.3 (n=4)a
Aluminum
Hydroxide
No data
Aluminum
Diethylphos-
phinate
-0.44a
Melamine
Polyphosphate
<-2a
Silicon
Dioxide
(amorphous)
No data
Magnesium
Hydroxide
No data
a Estimated. b Estimated based on proprietary components with MW <1,000.
Bioaccumulation Potential
Relevance to exposure: Indicates the degree to which a chemical substance may increase in concentration within a trophic level. Bioconcentration describes the increase in
tissue concentration relative to the water concentrations (environmental sources); bioaccumulation generally includes dietary and environmental sources. As chemicals
bioconcentrate or bioaccumulate, there is a higher potential for them to reach a level where a toxic effect may be expressed. Estimated and/or measured bioconcentration and
bioaccumulation values are presented as ranges based on relevant DIE hazard categories for each chemical. The DIE Alternatives Assessment criteria for bioaccumulation
potential considers both the bioaccumulation factor (BAF) and bioconcentration factor (BCF) values, as follows: Very High (VH) if BAF (log BAF) or BCF (log BCF) is
>5,000 (>3.7); High (H) if BAF or BCF is between 5,000 (3.7-3) and 1,000; Moderate (M) if BAF or BCF is between < 1,000 and 100 (<3-2); and Low (L) if BAF or BCF is
<100 (<2) (see DfE Program Alternatives Assessment Criteria for Hazard Evaluation).
TBBPA
Moderate
(100-<1,000)
D.E.R. 500
Series
High
(l,000-5,000)b
DOPO
Low
(<100)b
DowXZ-
92547
High
(l,000-5,000)b
Fyrol PMP
High
(l,000-5,000)b
Aluminum
Hydroxide
Low
(<100)a
Aluminum
Diethylphos-
phinate
Low
(<100)a
Melamine
Polyphosphate
Low
(<100)b
Silicon
Dioxide
(amorphous)
Low
(<100)a
Magnesium
Hydroxide
Low
(<100)a
a Based on professional judgment. b Based on estimated data.
5-6
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Table 5-2. Key Physical/Chemical and Fate Properties of Flame-Retardant Chemicals (Continued)
Persistence
Relevance to exposure: Indicates the length of time required for a chemical substance to be completely converted to small building blocks including water, carbon dioxide, and
ammonia ("ultimate degradation"). Persistence is typically expressed as a "half-life", which is the time for the amount of the substance to be reduced by one half. For a DfE
chemical alternatives assessment, persistent chemicals include those that have metabolic or degradation products that have long half-lives. The longer a chemical or its
degradation/metabolism products exist in the environment, the higher the likelihood for human or environmental exposure. "Compartments" refer to those environmental media
to which chemicals may partition and include soil, sediment, water and air as standard compartments for fate assessment. Persistence is considered Very High (VH) if the half-
life is >180 days or recalcitrant; High (H) if the half-life is 60-180 days; Moderate (M) if the half-life is <60 days but >16 days; Low (L) if half-life is <16 days OR readily
passes biodegradability test not including the 10-day window; and Very Low (VL) if passes biodegradability test with 10-day window (see DfE Program Alternatives
Assessment Criteria for Hazard Evaluation).
TBBPA
High
(60-180 days)
D.E.R. 500
Series
Very High
(>180 days)c
DOPO
High
(60-180 days)3
DowXZ-
92547
Very High
(>180 days)c
Fyrol PMP
Very High
(>180 days)c
Aluminum
Hydroxide
High
(60-180 days)b
Aluminum
Diethylphos-
phinate
High
(60-180 days)b
Melamine
Polyphosphate
High
(60-180 days)b
Silicon
Dioxide
(amorphous)
High
(60-180 days)b
Magnesium
Hydroxide
High
(60-180 days)b
' Based on results from biodegradation estimation model. b Based on professional judgment. ° Estimated based on polymer assessment literature (Boethling and Nabholz, 1997).
5-7
-------
5.2 Potential Occupational Releases and Exposures
The unit operations associated with each part of the PCB manufacturing supply chain result in a
unique set of potential release points and occupational exposures to flame-retardant chemicals.
This section provides a general overview of occupational pathways and routes of exposure, and
then identifies the specific processes and corresponding potential release and exposure points for
the unit operations associated with the manufacturing of flame retardants, epoxy resins,
laminates, and PCBs. It should be noted that many of the potential occupational exposures
identified here have been reduced or eliminated by the use of engineering controls and personal
protective equipment. Also, the level of exposure will vary considerably between workers and
the general population. Some releases will only result in exposure for workers, while other
releases result in exposures for the environment and the general population.
Inhalation Exposures
The physical state of the chemical during chemical manufacturing and downstream processing
significantly affects the potential for inhalation exposure of workers. In particular, the physical
state can result in three types of inhalation exposures that should be evaluated.
Dust: Chemicals that are manufactured, processed, and used as solids have the potential to result
in occupational exposure to fugitive dusts. The potential for fugitive dust formation depends on
whether the solid chemical is handled in the crystalline form, as an amorphous solid, or as a fine
powder, as well as the particle size distribution and solids handling techniques. If there is
exposure to dust, the level of exposure is directly proportional to the concentration of chemical in
the particulate form. Therefore, a flame retardant that is used at a lower concentration results in a
decreased exposure from this pathway and route (assuming that an equivalent amount of dust is
inhaled).
When assessing occupational exposures to flame-retardant chemicals, it is important to note the
physical state of the chemical at the potential point of release and contact. The pure chemical
may be manufactured as a solid powder, indicating a potential exposure to dust. However, it may
be formulated into solution before any workers come in contact with it, thereby eliminating
inhalation exposure to dust as a potential route. It is also important to note that the size of the
dust particles may have a profound influence on the potential hazards associated with inhalation
exposures for those materials that are not anticipated to be absorbed in the lungs. For these
materials, the potential hazards are typically associated with smaller, respirable particles
(generally those less than 10 microns in diameter).
Vapor: Exposure to vapors can occur when liquid chemicals volatilize during manufacturing,
processing, and use. Most chemical manufacturing operations occur in closed systems that
contain vapors. However, fugitive emissions are expected during open mixing operations,
transfer operations, and loading/unloading of raw materials. More volatile chemicals volatilize
more quickly and result in greater fugitive releases and higher occupational exposures than less
volatile chemicals. Therefore, vapor pressure is a key indicator of potential occupational
exposures to vapors.
5-S
-------
Mist: Both volatile and nonvolatile liquids can result in inhalation exposure if manufacturing or
use operations result in the formation of mist. It is unlikely that flame-retardant chemicals used
in PCBs will be applied as a mist.
Dermal Exposures
Occupational dermal exposure is also affected by the physical state of the chemical at the point
of release and contact. For example, the likelihood of liquids being splashed or spilled during
sampling and drumming operations is different than for similar operations involving polymerized
solids, powders, or pellets. Dermal exposure is also generally assumed to be proportional to the
concentration of chemical in the formulation. For example, the dermal exposure from contacting
a pure chemical is greater than the exposure from contacting a solution that contains only 10
percent of the chemical. Screening-level evaluations of occupational dermal exposure can be
based on the worker activities involving the chemical. For example, there may be significant
exposure when workers handle bags of solid materials during loading and transfer operations.
Maintenance and cleanup activities during shutdown procedures, connecting transfer lines, and
sampling activities also result in potential dermal exposures.
Ingestion Exposures
Occupational exposures via ingestion typically occur unintentionally when workers eat food or
drink water that has become contaminated with chemicals. Several pathways should be
considered. Often the primary pathway is poor worker hygiene (eating, drinking, or smoking
with unwashed hands). First, dust particles may spread throughout the facility and settle (or
deposit) on tables, lunchroom surfaces, or even on food itself. Vapors may similarly spread
throughout the facility and may adsorb into food and drinking water. Another potential pathway
for ingestion occurs from dust particles that are too large to be absorbed through the lungs. These
"non-respirable particles" are often swallowed, resulting in exposures from this route. While
ingestion is considered to be a realistic route of exposure to workers, it is often considered less
significant when compared to inhalation and dermal exposures, based on the relative exposure
quantities. On the other hand, ingestion during consumer use and to the general population is
often as significant as or more important than the inhalation and dermal routes. If persistent and
bioaccumulative compounds get into the environment and build up in the food chain, they can
become a significant exposure concern.
5.2.1 Flame Retardant and Epoxy Resin Manufacturing
The specific unit operations, operating conditions, transfer procedures, and packaging operations
vary with the manufacture of different flame-retardant and resin chemicals. Potential releases
and occupational exposures will depend on each of these parameters. While it is outside the
scope of this report to identify and quantify the releases and exposures associated with individual
chemicals, this section presents a general description of typical chemical manufacturing
processes and identifies potential releases.
Figure 5-2 presents a generic process flow diagram for epoxy resin manufacturing. Production
volumes and batch sizes associated with flame-retardant and epoxy resin chemicals typically
require the raw materials to be stored in large tanks or drums until use. The first step in most
5-9
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epoxy resin manufacturing processes for standard Flame Resistant 4 materials is to load the raw
materials into some type of reactor or mix tanks - as shown in Figure 5-2, the tanks labeled as
liquid epoxy resin and reactive flame retardant (e.g. TBBPA) hopper. Next, large-quantity
liquids are typically pumped into the reactor, and small-quantity raw materials may be manually
introduced or carefully metered via automated systems. Releases may occur from these
operations, but occupational exposure potential is typically small due to the number of safety
procedures and engineering controls in place.
Throughout the resin manufacturing process, there are several release points that may pose an
exposure risk to workers: packaging operations, leaks from pumps and tanks, fugitive emissions
from equipment, cleaning of process equipment, and product sampling activities. Additionally,
crude or finished products are often stored on-site in drums, day-tanks, or more permanent
storage vessels until the flame-retardant epoxy resin is packaged and shipped to the laminator.
The transfer and packaging operations, as well as any routine and unplanned maintenance
activities, may result in releases of and exposures to hazardous chemicals.
5-10
-------
Figure 5-2. Epoxy Resin Manufacturing Process (example with TBBPA as reactive FR)
-P
8isphenol-A
Ctiustk Carbonate
epiehlortiydrin
ci r.
.....
Sioroge
^^^,^^^
S'c-ngc
hi
___^^
Storage
Delivery to Limintfor
5-11
-------
5.2.2 Laminate and Printed Circuit Board Manufacturing
The laminate and PCB manufacturing processes, summarized in Figure 5-3 and Figure 5-4, can
result in occupational exposures to process chemicals if protective measures are not put in place.
The potential release of flame-retardant chemicals from laminates is not known, but is probably
very low, if there is any at all. As shown in Figure 5-3, the laminator combines the flame-
retardant epoxy resin with a curing agent (or hardener) and a catalyst in a mix tank as a first step
of the laminate manufacturing process. From there, woven fiberglass mats are embedded with
the epoxy resin, resulting in prepreg sheets. A copper clad laminate (CCL) is then assembled by
layering the prepreg sheets with copper sheets and stainless steel caul plates, as shown in Figure
5-3. The finished CCL is then shipped to the PCB manufacturing facility.
As summarized in Figure 5-4, PCB manufacturing involves numerous chemical and
electrochemical processes to cut, drill, clean, plate, and etch conductive pathways. Almost all of
these processes involve immersion of equipment or work pieces into a series of process baths,
with each bath followed by a rinsing step. For example, the process of drilling holes in the PCB
involves a series of individual steps, including cleaning (or desmearing) the holes with chemicals
or gas plasma and plating the holes with copper, and each step requires at least one process bath
and rinsing.
Many PCB manufacturers have implemented relatively simple techniques to reduce the amount
of chemicals that enter wastewater, such as withdrawing equipment from tanks slowly to allow
maximum drainage back into the process tank (CA EPA, 2005). Most manufacturing facilities
prevent worker exposure through use of engineering controls, personal protective equipment, and
safe work practices.
5-12
-------
Figure 5-3. Laminate Manufacturing Process
StairJess Stic!
Caul Pkries
Lamination
Quality Assurance
Packaging
Shipp -s
5-13
-------
Figure 5-4. Printed Circuit Board Manufacturing Process
1. Etch conductive pathways on inner layers
Laminate cares
Photoresist, developing cher^cals
etching salljtion, res*st stripp|.rg
soluticr, clecring and oxidairg
chemicals
2. Combine layers
I
t
5. Etch conductive
pathways on outer layers
4. Plate tin or tin-Iced etch
resist
Etching solution, resist stripping
solutoar.and cleaning chemicals
aoQ&ao
00004X1
Photcrcsiist and de
chemicals for plating etch resist
3. Drill clean (i
ond plate holes
0
a
QOaOOO
a
o
a
t
f "\
/ Chemicals or gas plasma fop \
desmeoi-irxj, chemicals and metal |
\ tons for ccppcr platir^ /
U LJ
V
6. Apply surface ftni:h(ei)
Chemicals for plating metals or
7. 5tencil legend, clean
circuit board (optional)
Irk. water, and/or civcr solvents
8. Attach electronic
component: to circuit board
(may be done at electronics
manufacturing facility)
5-14
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5.2.3 Best Practices
Incorporating best practices into the manufacturing process can reduce the potential for
exposure. The Bromine Science and Environmental Forum (BSEF) set up the Voluntary
Emissions Control Action Programme (VECAP) "to manage, monitor and minimize industrial
emissions of brominated flame retardants into the environment through partnership with Small
and Medium-sized Enterprises." The program started with decabromodiphenyl ether in Europe.
VECAP members follow six central steps to continually improve their processes and reduce
emissions: (1) commitment to the VECAP code of good practices; (2) self-audit; (3) mass
balance; (4) baseline emissions survey; (5) emissions improvement plan; and (6) implementation
and continuous improvement (BSEF, 2007).
ISO, the International Organization for Standardization, has also developed a series of
environmental management standards under the 14000 label. ISO 14000 standards establish a
"holistic, strategic approach" for continually reducing negative environmental impacts. They are
intended to cover a wide range of operations, and thus are not specific to brominated flame
retardants (ISO, 2007).
5.3 Potential Consumer and General Population Exposures
Exposures to consumers and the environment are different from exposures to workers and should
be evaluated separately for a number of reasons. Occupational exposures typically result from
direct contact with chemicals at relatively high concentrations while workers are conducting
specific tasks. Conversely, consumers may be exposed over a much longer period, but to a much
smaller level because the chemical is incorporated into the product. Also, the general population
and the environment will be exposed via different pathways and routes from workers and
consumers. For example, a person who does not own a product containing a flame-retardant PCB
may still be exposed if the chemical leaches from the disposed product into the drinking water
supply. Once in the water supply, groundwater, or surface water, it can be ingested by people or
consumed by fish and other animals. Similarly, if the chemical is released to the atmosphere
during manufacture, use, or disposal, it may settle out on food crops and be ingested directly by
people, or by cattle or other livestock. If the chemical is bioaccumulative, it may concentrate in
the animal and reach people through the food chain. For these reasons, exposure to the
environment and the general population should be assessed independently from occupational
exposure.
A quantitative exposure assessment is outside the scope of this report. However, the primary
pathways and routes from environmental, general population, and consumer exposures are
discussed in the following sections. Important chemical-specific factors that may help the reader
compare potential exposure between various flame-retardant alternatives are also discussed.
5.3.1 Physical and Chemical Properties Affecting Exposures
As previously discussed, the physical and chemical properties of a chemical often determine the
pathways and routes of exposure. In addition, the physical and chemical properties will affect
how the chemical becomes distributed in the environment once it is released, which will, in turn,
influence the potential for the chemical to be transported from the release point to the receptor.
5-15
-------
Information about persistence, bioaccumulation, and physical and chemical properties affecting
transport in the environment is presented in Section 4.3 of this report as well as Table 5-2.
As discussed in Chapter 3, flame-retardant chemicals can be classified as either additive or
reactive and this distinction may affect exposure. Additive flame retardants are added to a
manufactured product without bonding or reacting with the product, whereas reactive flame
retardants are chemically reacted into the raw materials that are used to make the final product.
As of 2008, most PCBs use reactive TBBPA, which loses the identity of the starting monomer
material during polymerization. Because they are chemically bound to PCBs, reactive flame
retardants are much less likely to pose occupational, consumer, or environmental exposure
concerns than additive flame retardants. Moreover, the polymerization processes are typically
conducted in totally enclosed systems, thus minimizing the potential for occupational exposure.
It should be noted, however, that reactive chemicals or close analogs could be released from the
finished product if a portion of the chemicals is not completely reacted during the polymerization
process. According to a 1995 study, a trace amount of starting TBBPA material is unreacted after
polymerization (4 micrograms per gram) (Sellstrom and Jansson, 1995).
5.3.2 Consumer Use and End-of-Life Analysis
Consumer Use
The nature of exposure to PCBs during use will vary with the composition of the product and the
manner in which the product is used. However, little information existed in the literature in 2008
about the emissions potential of alternative flame retardants from the use of electronic products.
Similarly, little to no research has addressed whether the type of flame retardants used in PCBs
potentially affects these emissions.
Several studies have examined the potential of brominated flame retardants to volatilize or offgas
from electronic devices. A study conducted by the German laboratory ERGO, which investigated
offgassing potential of TBBPA from computers under both real-world conditions and chamber
conditions, found that all emissions of TBBPA were associated with the housing material
(additive application of TBBPA), none with the printed circuit boards (reactive application of
TBBPA) (HDPUG, 2004). The German Federal Institute of Materials Testing also conducted
chamber emission testing of flame retardants from electronic articles and construction products.
They found very low emissions, even at the elevated operating temperatures of computers
(Kemmlein et al., 2003). Beard and Marzi (2006) investigated the offgassing potential of
thermoplastic polymers containing phosphorus-based and brominated flame retardants by
simulating extreme indoor car heat conditions as a worst case scenario; the study found very low
levels of volatilization (0 to 6 mg/kg).
Without further information on the exposure potential associated with printed circuit board use,
the differences between flame-retardant alternatives cannot be estimated. Additive flame
retardants, which are not commonly used in PCBs, are more likely to generate emissions than
reactive flame retardants. However, for additive flame retardants the potential for offgassing is
directly related to the volatility of the chemical (vapor pressure), which again is related to
molecule size and weight.
5-16
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End-of-Life Pathways
The amount of electronic waste (e-waste) generated annually in the U.S. is growing rapidly.
According to an EPA study, the amount of electronic products either recycled or disposed of
annually increased from an estimated 1.1 million tons in 1999 to 2.2 million tons in 2005 (OSW
1, 2007). While electronics represent less than 2 percent of the total municipal solid waste
stream, electronics contain many toxic substances that can adversely affect the environment and
human health (OSW 1, 2007).
In the U.S., used electronic goods are typically purchased by equipment handlers, such as
brokers and liquidation or auction services, or by equipment processors, such as refurbishers and
recyclers. Most used electronic goods then undergo a series of tests to determine their condition.
If a device is in good condition, it is reused either in part or in whole. Devices not in satisfactory
condition become e-waste, and are sent to demanufacturing and destruction facilities where raw
materials are either disposed of or recycled.
The manner in which electronic waste is disposed of or recycled determines the potential
environmental and human health impacts.11 An EPA study indicates that 15 to 20 percent of e-
waste is recycled, and 80 to 85 percent is disposed of (includes landfill and incineration) (OSW
1, 2007). Of the e-waste that is recycled, a portion is shipped overseas. For example, 61 percent,
or 107,500 tons of cathode ray tubes were shipped overseas in 2005 for remanufacture or
refurbishment (OSW 2, 2007). Of the e-waste shipped overseas, an unknown portion is
disassembled and recycled under largely unregulated conditions. The following sections describe
disassembly and recycling practices typical of unregulated overseas conditions and summarize
the nature of their potential impact.
Recycling
As Figure 5-5 shows, the PCB recycling process can involve both thermal processing, such as
smelting to recover precious metals, and nonthermal processing, such as disassembly, shredding,
separation, and chemical treatment. The potential level of exposure to workers and the general
population that results from these processes will vary depending on the type of operation
employed. Many recycling operations employ these methods in safe conditions that minimize the
potential for exposure, and recover valuable metals that are part of finished boards.
1: According to a 2005 UN report, up to 50 million metric tons of e-waste is generated annually. In the U. S., the
amount of e-waste is increasing at three times the rate of general waste, http://www.rrcap.unep.org/policy2/13-
Annex%204a-e-wastes%20SEPD2.pdf
5-17
-------
Figure 5-5. Sketch of the PCB Recycling Process (Li et al., 2004)
PCB
I
Composition Analysis
Hydrometallurgical
Processing
I
Disassembly
Reusable Units
Toxic Units
Shredding/Separation
Pyrolysis
Mechanical
Processing
Smelting
The thermal process of smelting separates valuable metals, such as gold, silver, platinum,
palladium, selenium, and copper, from impurities in PCBs (Figure 5-6). The process operates by
heating PCBs in a furnace to about 1,200 to 1,250°C in the presence of a reducing agent, which
is usually carbon from fuel oil or the organic portion of PCBs. Silicate, such as silicon dioxide, is
also added to help control reaction temperatures, and excess process gases are burned and
purified to remove contaminants (Kindesjo, 2002). Therefore, silicon dioxide-based flame
retardants are beneficial to the smelting process (Lehner, 2008).
PCBs
Figure 5-6. Smelting Process (Kindesjo, 2002)
Fuel
Oil Silicate
1 1
s * Smelting
1
Process
Furnace
1
Slag
Metals
^ continue
recovery
process
gasses
The smelting process generates two layers inside the furnace, a top layer of slag and a bottom
layer of "black copper." The bottom black copper layer can be directly sent to a copper recovery
unit, such as a copper converter or leaching and electrowinning facility (Umicore, 2007). The top
layer of slag is further processed to separate metals from impurities. After slag processing is
complete, leftover slag is deposited in impoundment areas (Kindesjo, 2002).
5-18
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In the absence of proper control equipment, the smelting process may pose risks to workers and
the public through exposure to toxic chemicals. Halogenated flame retardants, for example, can
lead to the formation of dioxins during the smelting process if proper safety measures are not
installed (Tohka, 2002). However, the three primary smelters in the world as of 2008 - Boliden,
Umicore, and Noranda - have learned how to operate with high loads of halogenated electronic
scrap and effectively control emissions of dioxins and furans, mercury, antimony, and other toxic
substances. In addition to the potential emission of toxic chemicals, high operating temperatures
may create occupational hazards. High loads of bromine or chlorine may induce corrosion of
gas-cleaning equipment. In sensitive areas, a process step for halogenide recovery may need to
be added (Lehner, 2008).
In contrast to the recycling practices described above, a large portion of the e-waste shipped
overseas to China, India, Pakistan, and other developing countries is subjected to unregulated
recycling practices that may pose significant exposure concerns. Much of the PCB waste in
unregulated operations is subject to open burning and acid leaching to recover precious metals.
The Basel Action Network (BAN), which has visited open burning sites in Asia, reports that the
general approach to recycling a circuit board first involves a de-soldering process. The PCBs are
placed on shallow wok-like grills that are heated underneath by a can filled with ignited coal. In
the wok-grill is a pool of molten lead-tin solder. The PCBs are placed in the pooled solder and
heated until the chips are removable, and then the chips are plucked out with pliers and placed in
buckets. The loosened chips are then sorted between those valuable for re-sale and those to be
sent to the acid chemical strippers for gold recovery. After the de-soldering process, the stripped
circuit boards go to another laborer who removes small capacitors and other less valuable
components for separation with wire clippers. After most of the board is picked over, it then goes
to large scale burning or acid recovery operations. It is this final burning process that potentially
emits substantial quantities of harmful heavy metals, dioxins, beryllium, and poly cyclic aromatic
hydrocarbons (PAHs) (BAN and SVTC, 2002). The chemicals released through these processes
can be inhaled by workers or could leach into the soil and water surrounding the area. In 2005,
Greenpeace collected industrial wastes, indoor dusts, soils, river sediments, and groundwater
samples from more than 70 industrial units and dump sites in Guiyu, China, and New Delhi,
India, and found elevated levels of lead, tin, copper, cadmium, antimony, polybrominated
diphenyl ethers, and polychlorinated biphenyls (Greenpeace, 2005).
In terms of the size of the population potentially at risk from open burning practices, the local
government website of Guiyu reported that the city processes 1.5 million tons of e-waste every
year, resulting in $75 million in revenue (Johnson, 2006). The People's Daily, the state-run
newspaper, reported in 2007 that Guiyu's more than 5,500 e-waste businesses employed more
than 30,000 people, and state media estimated that almost 9 out of 10 people in Guiyu suffered
from problems with their skin, nervous, respiratory, or digestive systems, which may be linked to
these practices (Chisholm and Bu, 2007).
In order to better understand the effects of combustion processes, the relationship between
specific combustion scenarios and the release of specific quantities of harmful substances has
been further analyzed as part of this project. The results of these tests are presented in Chapter 6.
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Landfills
E-waste sent to a landfill can lead to the creation of leachate (i.e., the mixture of rainwater and
liquids within the waste). This leachate has the potential to seep into the ground or drain into
nearby surface water, where it could affect the environment and have a negative impact on food
and water supplies.
Most teachability studies as of 2008 in the literature have focused on the potential for discarded
electronic devices to leach lead and other heavy metals. A relatively small number of these
studies have investigated teachability potential of brominated flame retardants, and in general,
have found either no or very small concentrations of brominated compounds in the leachate.
When brominated flame retardants are added versus reacted into the resin system, the potential
for the brominated flame retardants to leach from PCBs is much greater (KemI, 1995).
A study conducted by Beard and Marzi (2006) investigated the teachability potential of
phosphorus-based and brominated flame retardants from thermoplastic polymers and found that
small amounts of phosphorus and bromine respectively leached from the polymer. Another study
(Yoneda et al., 2002) reported that a small amount of phosphate ions leached from a Fujitsu-
developed dielectric material consisting of a bisphenol A epoxy with an additive type organic
phosphate in hot water and aqueous alkaline solutions. When Fujitsu developed and tested a
dielectric material consisting of a naphthalene-based epoxy with reactive-type organic
phosphate, no phosphate ions leached from the material.
Aside from the studies referenced above, little information exists in the literature about the
teachability potential of alternative flame retardants in landfill environments. Similarly, little to
no research has addressed whether the type of flame retardants used in PCBs potentially affects
the teachability of heavy metals.
5.4 Methods for Assessing Exposure
The European Union (EU)'s risk assessment of TBBPA offers insight into how personal and
environmental exposure can be evaluated for flame-retardant chemicals. The EU risk assessment
consists of two parts: the human health assessment, which was finalized in 2006, and the
environmental assessment, which remains in draft form. As part of the human health and
environmental risk assessments, exposure assessments have been conducted to estimate the
levels of TBBPA released in occupational settings and in the general environment. In both, the
EU differentiated between reactive and additive TBBPA and considered different stages of the
life cycle when estimating releases. While the results of the EU risk assessment are not being
used as part of this partnership project, Table 5-3 and Table 5-4 highlight some of the key
methods and assumptions used to estimate emissions of TBBPA used as a reactive flame
retardant in epoxy and other resins.
In the human health exposure assessment, the term exposure is used to denote personal exposure
without the use of any personal protective equipment. The EU used both measured and predicted
exposure data. Given the lack of TBBPA exposure data, the United Kingdom (UK) Health and
Safety Executive (HSE) commissioned sampling studies within the UK at four sites: two sites
involved in the production of polymers where TBBPA is incorporated into the finished product
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(one of which manufactures resin laminates), and two sites where polymer products are recycled.
The EU supplemented the measured exposure data with predicted data from the EASE
(Estimation and Assessment of Substance Exposure) model, which is widely used across the EU
for occupational exposure assessment of new and existing chemicals.
Table 5-3. Human Health Exposure Assessment (EU Risk Assessment, 2006)
Life-Cycle
Stage
Key Methods/Assumptions
Source of Data
Production
of laminates
Inhalation exposure;
HSE visited a manufacturing facility of copper/resin laminates used for PCBs in 2002
to measure personal inhalation exposure. Used one personal sampler during the
bromination step and multiple personal and static samplers during other steps of the
laminate process. Due to uncertainty surrounding the measured estimates, EU used
EASE model to estimate "typical" and "worst-case" inhalation values for bromination
and other laminate production steps.
Dermal exposure:
EASE model used to estimate "typical" and "worst-case" dermal values for
bromination and other laminate production steps.
Sampling results
from 2002 study at
UK laminate
manufacturing
facility; EASE model
Computer
recycling
Inhalation exposure;
HSE visited recycling facility where PCBs are shredded and exported for recovery of
precious metals in 2002. Used personal and static samplers during shift. EU used
EASE model to estimate "typical" and "worst-case" inhalation exposures.
Dermal exposure:
EASE model used to estimate dermal exposure values. Predicted to be very low;
consequently, dermal exposure values not used by EU in exposure assessment.
Sampling results
from 2002 study at
UK recycling facility;
EASE model
PCB
Assembly
Inhalation exposure;
Results of Sjodin et al., 2001 study, which measured levels of TBBPA in a factory that
assembles PCBs, used to establish "typical" and "worst-case" inhalation values.
Dermal exposure:
Dermal exposure assumed to be negligible given the low levels of free TBBPA in
PCBs.
Sjodin etal., 2001;
professional
judgment of risk
assessors
Office
environment
Inhalation exposure;
Results of Sjodin et al., 2001 study, which measured levels of TBBPA in a factory that
assembles PCBs, used to establish "typical" and "worst-case" inhalation values.
Dermal exposure:
Dermal exposure assumed to be negligible given the low levels of free TBBPA in
PCBs.
Sjodin etal., 2001;
professional
judgment of risk
assessors
Plastic
recycling
Inhalation exposure;
EASE model used to predict "typical" and "worst-case" inhalation values.
Dermal exposure:
EASE model predicted dermal exposure to be very low; consequently, dermal
exposure values not used by EU in exposure assessment.
EASE model
Consumer
exposure
EU concluded that consumer exposure to TBBPA is likely to be insignificant, and that
any attempt to quantify it would result in significant errors due to the small exposure
levels anticipated.
Professional
judgment of risk
assessors
Indirect
exposure via
environment
BUSES 2.0 model used to estimate the concentrations of TBBPA in food, air, and
drinking water.
BUSES 2.0 model
In the environmental exposure assessment, the EU estimated environmental releases using
industry-specific information, supplemented by defaults for life-cycle stages where sufficient
industry-specific information was unavailable. These are used together with fate and behavior
data to derive predicted environmental concentrations (PECs) in different media. The specific
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methods used in the PEC calculations are described in the EU's Technical Guidance Document
on Risk Assessment, last revised in 2003 (EU Technical Guidance Document, 2003).
Table 5-4. Environment Exposure Assessment (EU Risk Assessment, 2007 draft)
Life-Cycle
Stage
Production
Use/
Processing
Lifetime of
Products
Recycling
and Disposal
Key Methods/Assumptions
Emissions associated with production not considered in the risk assessment since no
TBBPA is currently produced in the EU.
Total amount of TBBPA used in the EU estimated at 6,500 tonnes per year, of which
90% (or 5,850 tonnes per year) assumed to be reactive flame retardant in epoxy and
other resins.
Default emissions factor of 0.001% to air and 0.001% to water used due to a lack of
specific release information for EU sites.
Levels of residual TBBPA present in finished epoxy resins assumed to be <0.02% by
weight of the resin, or <0.06% of the amount of TBBPA used to make the resin.
Releases associated with finished products based on estimated volume of TBBPA used
as a reactive flame retardant in finished products, as well as estimate that 0.06% of the
amount of TBBPA used to make epoxy resin is present, or free, for release.
Amount leached from products over their lifetime is assumed to be very low for
purposes of this risk assessment.
A yearly emission factor of S.OxlO"5 % (of the residual amount of TBBPA in polymers)
due to volatilization used. Assumed that reactive flame retardants volatilize at same
release factor as additive flame retardants.
No loss of residual TBBPA through wear and weathering is assumed over the lifespan
of products where TBBPA is used as a reactive flame retardant
Emissions of TBBPA from the collection, separation, and regrinding of PCBs (or other
plastics where TBBPA is used as a reactive flame retardant) assumed to be limited.
EU Data Source
—
2003 consumption
data from EFRA and
EBFRIP
Technical Guidance
Document 2003
Information reported
by Industry as part of
survey; no references
provided
Information reported
by Industry as part of
survey; no references
provided
Professional
judgment of EU risk
assessors
Emissions data from
ERGO 2002
Professional
judgment of EU risk
assessors
Professional
judgment of EU risk
assessors
5.5 Chemical Life-Cycle Considerations
This section discusses the environmental and human health impacts for each of the ten flame
retardants that can occur throughout the life cycle: from raw material extraction and
manufacture, through product use, and finally at end of life of the material or product. For each
stage of the chemical's life cycle, this section addresses potential exposure concerns for workers,
the general population, and the environment. It should be noted that a greater level of
information exists for TBBPA as compared to the more recently developed flame-retardant
alternatives.
5.5.1 TBBPA
TBBPA is used as both an additive and reactive flame retardant in a wide variety of electronic
equipment. As discussed in Section 3.2, TBBPA is most commonly used as a reactive flame
retardant in PCBs and is incorporated through chemical reactions with the epoxy resin.
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Raw Material Extraction
Bromine is produced from salt brines in the United Stated and China, from the Dead Sea in Israel
and Jordan, and from ocean water in Wales and Japan (BSEF, 2007). Bromine is typically
isolated via a series of redox reactions involving chlorine, sulfur dioxide and acid (MIT, 2003;
York, 2007). During these reactions the seawater is acidified and then chlorinated to oxidize
bromide to elemental bromine. At this stage, the bromine is not concentrated enough to
practically collect and liquefy, so sulfur dioxide is added to reduce the bromine to hydrobromic
acid. Chlorine is then added to re-oxidize hydrobromic acid to elemental bromine. At this point,
bromine gas is collected and condensed (Grebe et al., 1942). While caustic substances are
involved in these processes, they are typically contained in an enclosed tower, which mitigates
worker exposure and environmental release.
Manufacture of Flame Retardant, Laminate, and PCB
TBBPA is produced by brominating bisphenol A (BPA) in the presence of solvent. This reaction
is highly exothermic, and no catalyst is required. Co-products will depend on the solvent used
and the process conditions. The use of some solvents results in co-products, while the use of
other solvents does not result in co-products. Co-products are typically either sold as products or
disposed of as wastes.
Methanol and n-propanol are two examples of solvents that lead to the formation of co-products.
Use of methanol produces methyl bromide, and use of n-propanol produces n-propyl bromide
(Noonan, 2000). These co-products are typically removed through purification processes that can
include the use of caustic neutralizers.
In 2008, TBBPA was commercially produced by Albemarle Corporation (Magnolia, AR) and
Chemtura (El Dorado, AR). At that time, both corporations used proprietary processes that did
not yield methyl bromide (Haneke, 2002).
While commercially employed bromination processes are proprietary, most involve bromination
of BPA. Figure 5-7 gives a general overview of the main chemicals and reactions involved in
TBBPA production. Please note that Figure 5-7 is a general outline of processes involved, and is
not a complete list of chemicals or process steps.
Figure 5-7. Common Reactants and Processes Involved in TBBPA
Process 1 Process 2 Process 3 ^^^ .
Benzene -^* *• Phenol —-^—*• Bisphenol A -^*—"TBBPA
Propylene Acetone Bromine'
Process (1): Cumene hydroperoxide rearrangement involving benzene and propylene to form phenol - this is the
most common industrial process for producing phenol, accounting for approximately 97 percent of phenol
production. Acetone is also formed as a coproduct (Plotkin, 2006). Process (2): Condensation reaction between
phenol and acetone to produce bisphenol A. Process (3): Bromination of bisphenol A to produce TBBPA. In the
absence of an oxidant, HBr would be produced as a coproduct. Hydrogen peroxide can be used to convert HBr back
to Br2, forming water and avoiding this problem.
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While Figure 5-7 presents an overview of common reactants and processes involved in TBBPA
production, there are also other processes that can be involved in producing TBBPA. To analyze
the hazards associated with the production of any given TBBPA product, one would have to
trace the line of production and identify which methods were used and what chemicals were
involved, including catalysts, solvents, and other reagents.
Potential exposure to or release of TBBPA particulates may occur during manufacture or
subsequent loading/unloading, transfer, or mixing operations (those that occur before its
incorporation into the epoxy resin). When TBBPA is used as a reactive flame retardant, there
may be unreacted (or free) TBBPA left over in the resin, leading to the presence of free TBBPA
in the laminate and subsequently produced PCBs. The amount of free TBBPA is anticipated to
be relatively low when it is used as a reactive flame retardant, although quantitative data on the
amount of free TBBPA present in PCBs was limited at the time of report publication. Sellstrom
and Jansson (1995) found approximately 0.7 micrograms per gram in a basic extraction of PCB
filings from an off-the-shelf product purchased in Sweden (approximately 4 micrograms per
gram TBBPA used). Studies have been conducted by Nelco to investigate the amount of residual
TBBPA, but the results have not yet been published (PSB Corporation, 2006). One complication
is that it is possible to add TBBPA to the varnish rather than pre-reacting it with an epoxy (as is
done to make D.E.R. 500 Series). Even though all of the TBBPA should react, there is more
potential to have unreacted TBBPA present when it is added to the varnish. It is not known how
common this practice is.
D.E.R. 500 Series, the reaction product of TBBPA with an epoxy resin, may be released to the
environment from its use in PCBs through dust-forming operations during its manufacture or
subsequent loading/unloading, transfer, or mixing operations (those that occur before its
incorporation into the laminate or PCB). Increased health hazards for this reaction product arise
from the epoxy functional groups present on the polymer molecules. There may be unreacted
D.E.R. 500 Series present in the laminate and, subsequently, the PCBs produced. The amount of
free D.E.R. 500 Series is generally anticipated to be low given that it is incorporated as a reactive
flame retardant, although quantitative data on the amount of free material that may be present are
currently not available.
BPA, the unbrominated precursor to TBBPA, may also pose potential hazards to human health
and the environment. The EU's risk assessment of BPA in 2003 concluded that for occupational
exposures, "there is a need for limiting the risk" to workers based on eye and respiratory tract
irritation, effects on the liver, and reproductive toxicity (effects on fertility and on development)
during the manufacture of BPA and epoxy resins, as well as concerns for skin sensitization in all
occupational exposure scenarios where there is a potential for skin contact (EU, 2003). For
workers, consumers, and the general public, the EU concluded that further information and/or
testing is needed in relation to developmental toxicity at low doses. The EU also assessed
environmental hazards, concluding that further information is needed on the risk of BPA
production to aquatic and terrestrial organisms, as well as the risk of epoxy resin production on
aquatic organisms (EU, 2003). Steps have also been taken in the U.S. in recent years to identify
the hazards associated with BPA. For uses under the Toxic Substances Control Act, U.S. EPA
issued the BPA Action Plan12 in March 2010, which summarized hazard, exposure, and use
12 http://www.epa.gov/oppt/existingchemicals/pubs/actionplans/bpa action_plan.pdf
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information, and identified actions to address BPA in the environment based on concerns for
potential effects on aquatic species.13 The Action Plan states that dermal exposure to BPA may
occur in workers producing flame retardants during the loading/unloading of BPA from
containers, and that occupational exposure via inhalation is not expected (U.S. EPA, 2010). As
part of the Action Plan, U.S. EPA tasked its Design for the Environmental Program with
conducting an alternatives assessment for BPA in thermal paper. BPA and 19 potential chemical
alternatives in thermal paper were evaluated on their human health effects, ecotoxicty, and
environmental fate. A final version of this alternatives assessment was released in January
2014.14 The report also contains information on general exposure and lifecycle information on
BPA, and can be used to inform decision-making and to guide the development of new
alternatives. More information about the Agency's current efforts to address BPA can be found
at: http://www.epa.gov/oppt/existingchemicals/pubs/actionplans/bpa.html.
Use and End of Life
Since TBBPA is reacted with an epoxy resin to form D.E.R. 500 Series, which is then reacted
with a hardener to form a crosslinked polymer, low levels of unreacted TBBPA and D.E.R. 500
Series may remain in trace concentrations in PCBs; release of these low levels could
theoretically occur during the use and disposal of PCBs. Because TBBPA is difunctional15, there
is less potential for release compared to DOPO, which is monofunctional, and more potential for
release compared to Fyrol PMP, which is tetrafunctional. TBBPA has been detected in the air of
electronic recycling plants (Sjodin et al., 2001, 2003), although these facilities also recycled
products where TBBPA is used as an additive flame retardant. Although its water solubility is
low under neutral conditions, free TBBPA could also be released from PCBs in landfills that
come in contact with basic leachate. However, unlike other brominated flame retardants, TBBPA
is not very stable in air under basic conditions. In addition, there is potential for emissions of
brominated dioxins and furans or other by-products when products containing TBBPA are
combusted during end-of-life processes. Levels of exposure and any subsequent effects of
exposure to the reacted flame retardant products during the disposal phase of the life cycle, in
which flame retardants may become mobilized through direct intervention processes, such as
shredding, are unknown.
5.5.2 DOPO
Raw Material Extraction
Phosphorus is usually obtained from phosphate rock, which contains the mineral apatite, an
impure tri-calcium phosphate. Large deposits of phosphate rock are found in Russia, Morocco,
Florida, Tennessee, Utah, Idaho, and elsewhere (Lide, 1993). By one process, tri-calcium
phosphate, the essential ingredient of phosphate rock, is heated in the presence of carbon and
silica in an electric furnace or fuel-fired furnace. Elementary phosphorus is liberated as vapor
13 The U.S. Food and Drag Administration (FDA) is expected to take the lead on assessing potential human health
impacts associated with exposure to BPA. See
http://www.fda.gov/NewsEvents/PublicHealthFocus/ucm064437.htm.
14 http://www.epa.gov/dfe/pubs/projects/bpa/about.htm
15 A molecule with two reactive sites.
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and may be collected under water (Lide, 1993). While elementary phosphorus can form a
diatomic molecule with a triple bond, it more readily forms a tetrahedral ?4 molecule. ?4, also
called white or yellow phosphorus, exists in the gas phase and also as a waxy solid and viscous
liquid. The degree of purity determines the "whiteness" of the phosphorus. At room temperature,
phosphorus can exist in an amorphous or semi-crystalline state, called red phosphorus, which is
produced from white phosphorus by extended heating in an inert atmosphere (Calvert, 2004).
Some phosphorus-based flame retardants are based on phosphate esters derived from yellow
phosphorus. Approximately 80 percent of the global phosphorus is mined in China in the form of
phosphate ore (Shigeru, 2007). Yellow phosphorus produced from phosphorus ore co-produces
arsenic, mercury, lead and other heavy metals as impurities that should be well controlled and
treated before disposal of wastewater. If Chinese producers of yellow phosphorus appropriately
treat their wastewater, then there is little concern for environmental and human health effects.
However, improperly treated wastewater can lead to major adverse environmental impacts
(Shigeru, 2007).
Manufacture of Flame Retardant, Laminate, and PCB
Chemistry that can be used to make DOPO is shown below. The by-products of this chemistry
are salts of the Lewis acid (such as aluminum chlorohydrates) and NaCl from the second step.
PCI;
3
AICI3 (or other
Lewis acid)
Further chemistry must be performed to react DOPO into the thermoset backbone. The largest
manufacturer of organophosphorus flame retardants for electrical laminates at the time this
partnership was convened was Tohto-Kasei. The details of their product are not known, but it is
widely thought that their product is "DOPO-HQ", or the adduct of DOPO with hydroquinone as
shown below. This phenolic is then combined with an epoxy novolak and a catalyst in a solvent
to make a varnish suitable for electrical laminates. Fillers are typically added to these
formulations primarily to reduce costs.
OH M l^h OH
H202 /^ H 0-\JJ JL .DOPO
+ H^fj
DOPO OH
DOPO-HQ
Potential human and environmental exposure to DOPO may occur through dust-forming
operations from its manufacture or during loading/unloading, transfer, or mixing operations.
Dow XZ-92547, the reaction product of DOPO with an epoxy phenyl novolak, may be released
from PCBs as a fugitive emission during manufacture of resins and laminates, or during
subsequent loading/unloading, transfer, or mixing operations. The amount of Dow XZ-92547
that may be released from laminates or PCBs during their production and operational stages has
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not been determined quantitatively; however, the low vapor pressure of Dow XZ-92547 indicates
that it is not likely to undergo direct volatilization. Increased health hazards for this reaction
product arise from the epoxy functional groups present on the polymer molecules.
Use and End of Life
As a reactive flame retardant, DOPO is not expected to be released from laminates. Its vapor
pressure suggests that it has at least some potential to volatilize at elevated temperatures.
Potential releases of DOPO particulates from PCBs may arise during the disposal phase of the
life cycle via shredding or other operations where it may become mobilized. DOPO's water
solubility suggests that it may migrate from PCBs deposited in landfills if contact with water
ensues. Release of DOPO during the open burning of PCBs may also lead to environmental
exposures. Because it is monofunctional, there is more potential for release compared to TBBPA,
which is difunctional. DOPO may be released from PCBs during disposal or recycling, and
potentially through dust-forming operations, such as PCB shredding. Leaching of Dow XZ-
92547 from PCBs deposited in landfills is not likely given its low water solubility, high MW and
functionality. Leaching of DOPO is more likely given its relatively low MW and because it is
bound to the polymer by only one covalent bond. DOPO also oxidizes to a species containing a
P-OH group in place of the P-H group. The toxicological properties of this species are unknown.
Levels of exposure and any subsequent effects of exposure to the reacted flame retardant
products during the disposal phase of the life cycle, in which flame retardants may become
mobilized through direct intervention processes, such as shredding, are unknown.
5.5.3 Fyrol PMP
Raw Material Extraction
For a description of phosphorus extraction, please refer to the above entry for DOPO.
Manufacture of Flame Retardant, Laminate, and PCB
No information regarding the manufacture of Fyrol PMP was available at the time of publication
due to the chemical's proprietary nature.
Use and End of Life
As a reactive flame retardant, Fyrol PMP is not expected to be released from laminates, and its
low vapor pressure indicates that it is not likely to undergo direct volatilization. When PCBs are
openly burned, it is possible that high temperatures could break the phosphorous-carbon bonds
that hold Fyrol PMP to the crosslinked resin, which may result in the release of Fyrol PMP to the
environment. Because it is tetrafunctional, Fyrol PMP is less likely to be released than TBBPA
or DOPO, which are, respectively, difunctional and monofunctional. Even so, Fyrol PMP may be
released from PCBs during its disposal or recycling, potentially through dust-forming operations,
such as the shredding of PCBs. However, it is possible that methyl phosphonate may leach out of
PCBs due to hydrolysis of phenol-phosphonate bonds. Exposure to the reacted flame retardant
products during the disposal phase of the life cycle, in which flame retardants may become
mobilized through direct intervention processes, such as shredding, is unknown.
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5.5.4 Aluminum Diethylphosphinate
Raw Material Extraction
For a description of phosphorus extraction, please refer to the above entry for DOPO.
Manufacture of Flame Retardant, Laminate, and PCB
Potential human and environmental exposure to aluminum diethylphosphinate may occur
through dust-forming operations from its manufacture or during loading/unloading, transfer, or
mixing operations. No additional information regarding the manufacture of aluminum
diethylphosphinate was available at the time of publication in 2008 due to the chemical's
proprietary nature.
Use and End of Life
As an additive flame retardant, aluminum diethylphosphinate may also be released from
laminates and PCBs. After incorporation into the resin and/or the laminate, potential releases of
aluminum diethylphosphinate during the useful life cycle of PCBs is not anticipated, except by
an extractive processes upon contact with water. Potential releases of aluminum
diethylphosphinate particulates during the disposal of PCBs may arise during the disposal phase
of the life cycle via shredding or other operations where it may become mobilized. Its water
solubility suggests that it may also migrate from PCBs deposited in landfills upon contact with
water.
5.5.5 Aluminum Hydroxide
Raw Material Extraction
Aluminum is one of the most plentiful elements in Earth's crust, and is usually present as bauxite
ore. Bauxite can contain three different aluminum minerals, including gibbsite (A1(OH)3), and
bohmite and diaspore (different crystalline structures of AIO(OH)). Bauxite ore also typically
contains clay, silt, iron oxides, and iron hydroxides. The majority of bauxite is mined from
surface deposits, but some is excavated from underground deposits (International Aluminium,
2000). Nearly all of the bauxite consumed in the U.S. is imported (EPA, 2007).
Manufacture of Flame Retardant, Laminate, and PCB
Once bauxite is recovered from deposits and broken into manageable pieces, it is shipped to a
processing facility where it goes through the Bayer process. During this process, the bauxite ore
is washed, ground, and dissolved with caustic sodium hydroxide. While the end product of the
Bayer process is alumina (A12O3), aluminum hydroxide (A1(OH)3) can be isolated following the
precipitation step (see process steps below) (International Aluminium, 2000). In the past, more
than 90 percent of domestic bauxite conversion to alumina occured at refineries in Louisiana and
Texas (EPA, 2007).
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Bayer process steps:
1) Digestion—bauxite ore treated with heated sodium hydroxide solution to form sodium
aluminate:
Gibbsite: A1(OH)3 + NaOH -> Na+ A1(OH)4'
and
Bohmite and Diaspore: AIO(OH) + NaOH + H2O -> Na+ A1(OH)4"
2) Clarification—insoluble impurities (red mud) are separated from the suspension.
3) Precipitation—aluminum hydroxide crystals are added to the solution to seed the
precipitation of aluminum hydroxide crystals:
Na+ A1(OH)4" -> A1(OH)3 + NaOH
4) Calcification—the agglomerates of aluminum hydroxide are calcinated to produce pure
alumina. (Note that while this step is included in the Bayer process, it is not relevant to
the production of aluminum hydroxide; however, this is the reaction that occurs when
aluminum hydroxide acts as a flame retardant.)
2A1(OH)3 -> A12O3 + 3H2O
During clarification, clay, silt, iron oxides, iron hydroxides, and other non-aluminum
components are removed from the bauxite ore. These components are disposed of as "red mud,"
which is highly alkaline (pH ~ 13), and can be hazardous to human health and the environment.
Red mud is viewed as a corrosive and hazardous substance requiring careful handling (Liu et al.,
2007). While there are methods to reduce the hazard of red mud, its disposal can still be
problematic.
Use and End of Life
Once aluminum hydroxide is produced, it can be released into the environment as a fugitive
emission during loading/unloading, transfer, or mixing operations. After incorporation into a
PCB resin and/or the laminate, potential exposure to finely divided aluminum hydroxide
particulates is not expected during the remainder of the operational stages of the PCB life cycle.
Aluminum hydroxide parti culates may also be released during the disposal phase of the life cycle
where they can become mobilized through direct intervention processes (such as shredding
operations). The impact of aluminum hydroxide in smelting operations needs to be investigated
further due to concerns about impacts on slags. Aluminum hydroxide thermally degrades to
alumina in the smelting process. Alumina has a limited solubility in smelter slags. If large
concentrations are added, this may lead to either increased slag volumes or higher operational
temperatures, which lead to increased energy consumption (Lehner, 2008).
5.5.6 Magnesium Hydroxide
Raw Material Extraction
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There are several million tons of mineral magnesium hydroxide, called brucite, in Earth's crust
around the world (USGS, 2008; Amethyst, 2008). However, magnesium hydroxide is typically
recovered from seawater and magnesia-bearing brines, which constitutes an even greater and
more readily available resource than brucite. In 2007, magnesium oxide and other magnesia
compounds (including magnesium hydroxide) were recovered from seawater by three companies
in California, Delaware, and Florida; from well brines by two companies in Michigan; and from
lake brines by two companies in Utah (USGS, 2008).
Manufacture of Flame Retardant, Laminate, and PCB
Recovering magnesium hydroxide from brine and seawater typically involves the addition of
lime calcined dolime (CaO-MgO), which is obtained from a mineral source such as dolomitic
limestone (CaMg(CC>3)2). Magnesium-bearing brine and seawater contain varying
concentrations of calcium chloride (CaQ2) and magnesium chloride (MgQ2), which are mixed
with appropriate concentrations of calcined dolime and water (if necessary) to facilitate the
following reaction (Martin, 2008):
CaCl2 + MgCl2 + (CaO-MgO) + 2H2O -» 2Mg(OH)2 + 2CaCl2 + H2O
The resulting magnesium hydroxide exists as solid particles suspended in an aqueous phase
containing dissolved calcium chloride. The magnesium hydroxide particles settle to the bottom
of the aqueous suspension, where they are separated, filtered, and washed to remove chlorides
(Martin, 2008).
Hydrated lime (Ca(OH)2) can also be used to precipitate magnesium hydroxide via the following
reaction (NIEHS, 2001):
Ca(OH)2 + MgCl2 -» Mg(OH>+ CaCh
Potential human and environmental exposure to magnesium hydroxide may occur through dust-
forming operations from its manufacture, or during loading/unloading, transfer, or mixing
operations. As an additive flame retardant, it may also be released from laminates and PCBs.
Use and End of Life
After incorporation into the resin and/or the laminate, potential exposure to finely divided
magnesium hydroxide particulates is not expected during the remainder of the operational stages
of the PCB life cycle. Magnesium hydroxide parti culates may also be released during the
disposal phase of the life cycle where they can become mobilized through direct intervention
processes, such as shredding operations. The impact of magnesium hydroxide in smelting
operations needs to be investigated further due to concerns about impacts on slags. Magnesium
hydroxide thermally degrades to magnesium oxide in the smelting process. However,
magnesium oxide has a limited solubility in smelter slags. If large concentrations are added, this
may lead to either increased slag volumes or higher operational temperatures, which lead to
increased energy consumption (Lehner, 2008).
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5.5.7 Melamine Polyphosphate
Raw Material Extraction
For a description of phosphorus extraction, please refer to the above entry for DOPO.
Manufacture of Flame Retardant, Laminate, and PCB
A two-step process is typically used to prepare melamine polyphosphate (Patent Storm, 2002). In
the first step, melamine, urea, and an aqueous orthophosphoric acid solution (containing at least
40 wt percent orthophosphoric acid) are combined, mixed, and dehydrated to produce a powdery
product. In the second step, this powdery product is heated to between 240 and 340°C for 0.1 to
30 hours to obtain melamine polyphosphate (Patent Storm, 2002)
Potential human and environmental exposure to melamine polyphosphate may occur through
dust-forming operations from its manufacture or during loading/unloading, transfer, or mixing
operations. As an additive flame retardant, it may also be released from laminates and PCBs.
Use and End of Life
After incorporation into the resin and/or the laminate, potential releases of melamine
polyphosphate during the useful life cycle of PCBs is not anticipated, except by an extractive
process upon contact with water. Potential releases of melamine polyphosphate particulates
during the disposal of PCBs may arise during the disposal phase of the life cycle via shredding or
other operations where it may become mobilized. Its water solubility suggests that it may also
migrate from PCBs deposited in landfills upon contact with water.
5.5.8 Silicon Dioxide
Raw Material Extraction and Manufacture
Silicon dioxide, or silica (sand), is a naturally occurring compound. It is usually mined with open
pit or dredging mining methods, which have limited environmental impact (USGS, 2007).
Silicon dioxide can also be made synthetically in autoclaves under pressures ranging from 1,500
to 20,000 pounds per square inch and at temperatures of 250°C to 450°C (Lujan, n.d.). In some
cases, silicon dioxide is synthesized by adding an acid to a wet alkali silicate solution to
precipitate amorphous silicate, which is then filtered, washed, and dried (Degussa, 2007). The
conditions in which silicon dioxide is formed, such as temperature and pressure, determine its
structural properties, such as whether it is amorphous or crystalline. The structure of silicon
dioxide, in turn, affects its potential to cause harm to the environmental and human health.
Potential health concerns arise from the inhalation of finely divided parti culates that are
generally less than 10 microns in diameter. The potential health concerns for silicon dioxide, a
poorly soluble respirable particulate, arise from effects on the lungs as well as other effects that
may be linked to an adverse effect on the lungs. Assessment of the life cycle for the use of this
compound in PCBs suggests that inhalation exposure to finely divided silicon dioxide
5-31
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particulates may potentially occur through dust-forming operations from its manufacture or
during loading/unloading, transfer, or mixing operations.
Use and End of Life
After incorporation into the resin and/or the laminate, potential inhalation exposure to finely
divided silicon dioxide particulates is not anticipated during the remainder of the operational
stages of the PCB life cycle. Finely divided silicon dioxide particulates that are less than 10
microns may also be released to the air during the disposal phase of the life cycle, where they
can become mobilized through direct intervention processes (such as shredding operations). In
the smelting process, silicon dioxide-based flame retardants are preferred since silicon dioxide is
used as a flux in the process (Lehner, 2008).
5.6 References
Amethyst Galleries, Inc. The Mineral Brucite.
http://mineral.galleries.com/Minerals/OXIDES/brucite/brucite.htm (accessed 2008).
Basel Action Network (BAN) and Silicon Valley Toxics Coalition (SVTC). Exporting Harm:
The High-Tech Trashing of Asia. [Online] 2002. http://www.ban.org/E-
waste/technotrashfmalcomp.pdf (accessed 2007).
Beard, A.; Marzi, T. Sustainable phosphorus based flame retardants: a case study on the
environmental profile in view of European legislation on chemicals and end-of-life
(REACH, WEEE, ROHS). Proceedings of Going Green CARE Innovation 2006
Conference, Vienna, Austria, 2006.
Boethling, R.S.; Nabholz, J.V. Environmental assessment of polymers under the U.S. Toxic
Substances Control Act. Washington, DC: U.S. Environmental Protection Agency. 1997.
BSEF (Bromine Science and Environmental Forum). About Bromine.
http://www.bsef.com/bromine/what is bromine/index.php (accessed October 2007).
BSEF (Bromine Science and Environmental Forum). VECAP.
http://www.bsef.com/product_stew/vecap/ (accessed 2007).
California Environmental Protection Agency (CA EPA). CalGold: Business Permits Made
Simple. http://www.calgold.ca.gov/P2/3672.htm (accessed 2007).
Calvert, J. Phosphorus; 2004. http://mvsite.du.edu/~icalvert/phys/phosphor.htm (accessed 2007).
Chisholm, M.; Bu, K. China's e-waste capital chokes on old computers. Reuters [Online] July 11,
2007.
http://www.reuters.com/article/environmentNews/idUSPEK14823020070612?sp=true
(accessed 2007).
5-32
-------
Energy Trends in Selected Manufacturing Sectors: Opportunities and Challenges for
Environmentally Preferable Energy Outcomes. [Online] EPA: March, 2007.
http://www.epa.gov/sectors/pdf/energy/ch3-l .pdf (accessed 2007).
European Union (EU) Risk Assessment Report. 4,4'-isopropylidenediphenol (bisphenol-A).
[Online] European Chemicals Bureau: 2003. http://ecb.irc.it/DOCUMENTS/Existing-
Chemicals/RISK ASSESSMENT/REPORT/bisphenolareport325.pdf
European Union (EU) Risk Assessment Report. 2,2',6,6 '-tetrabromo-4,4 '-
isopropylidenediphenol. Part II Human Health. European Chemicals Bureau: 2006;
Vol. 63.
European Union (EU) Risk Assessment Report. 2,2',6,6 '-tetrabromo-4,4 '-
isopropylidenediphenol. Final Environmental Draft: June 2007.
Degussa. Specialty Silicates: Production Process, http://www.degussa-
fp.com/fp/en/gesch/specialtysilicas/herstellung/ (accessed 2007).
Florida Department of Environmental Protection (FL DEP). Surface Finishing / Electroplating
Issue. P2 Links [Online] 1999, 2, (3) http://www.p2pays.org/ref/19/18271.pdf (accessed
2007).
Grebe, J. J.;Bauman, W. C.; Robinson, H. A. Bromine Extraction [Online]. U.S. Patent 445,706,
1942. http://www.google.com/patents?id=bt5oAAAAEBAJ&dq=bromine+extraction.
(accessed 2007).
Greenpeace International. Recycling of Electronic Waste in China and India: Workplace and
Environmental Contamination. [Online] August 2005.
http://www.greenpeace.org/international/PageFiles/25134/recycling-of-electronic-
waste.pdf (accessed 2007).
Hageliiken, C. Improving metal returns and eco-efficiency in electronics recycling. Proceedings
of the 2006 IEEE International Symposium on Electronics & the Environment, San
Francisco, CA, May 8-11, 2006; pp 218-233. [Online]
http://www.preciousmetals.umicore.com/publications/ (accessed 2007).
Haneke, K. E. TetrabromobisphenolA [79-94-7]: Review of ToxicologicalLiterature. Integrated
Laboratory Systems: 2002.
High Density Packaging User Group International, Inc. (HDPUG). Environmental Assessment of
Halogen-free Printed Circuit Boards. DfE Phase //; Revised Final: January 15, 2004.
International Aluminium Institute. Aluminium Production, http://www.world-
aluminum.org/producti on/index.html (accessed 2007).
5-33
-------
International Organization for Standardization (ISO). Management Standards.
http://www.iso.org/iso/iso catalogue/management standards/iso 9000 iso 14000/iso 14
000_essentials.htm (accessed 2007).
Johnson, T. E-waste dump of the world. [Online]; The Seattle Times: April 9, 2006.
http://seattletimes.nwsource.com/html/nationworld/2002920133 ewaste09.html
(accessed 2007).
Keml. The Flame Retardants Project - A collection of reports on some flame- retardants and an
updated ecotoxicological summary for tetrabromobisphenol A. PMnr 10/95.
Kemikalieinspektionen, The Swedish Chemicals Inspectorate: Solna, Sweden 1995.
Kemmlein, S.; Hahn, O.; Jann, O. (2003): Emission of Flame Retardants from Consumer
Products and Building Materials. [Online]; Federal Institute for Materials Research and
Testing (BAM): Umweltbundesamt, Berlin, Germany, 2003; pp. 188.
http://www.umweltbundesamt.de/publikationen/emission-of-flame-retardants-from-
consumer-products (accessed 2007).
Kemp, P. Christ Water Technology Group. Printed Circuit Board Wastewater Recovery: Staying
in Compliance, Saving Money, and Improving Overall Product Quality.
http: //www. chri stwater-
americas.com/Merchant2/merchant.mv?Screen=PROD&Store Code=tenergycom&Prod
uct_Code=PC_Board_Wastewater (accessed 2007).
Kindesjo, U. Phasing out lead in solders: An assessment of possible impacts of material
substitution in electronic solders on the recycling of printed circuit boards. M.S. Thesis,
Lund, Sweden, October, 2002.
Lehner. Personal Communication by email between Kathleen Yokes and Theo Lehner, January
22, 2008.
Liu, Y.; Lin, C. Characterization of red mud derived from a combined Bayer Process and bauxite
calcination method. J. Hazard. Mater. 2007,146 (1-2), 255-261.
Lide, D. R., ed. CRC Handbook of Chemistry and Physics, 74th ed.; 1993/94, pp 4-21.
Lujan, M., Jr., Secretary. Crystalline Silica Primer. U.S. Department of the Interior.
Martin Marietta Magnesia Specialties, LLC (2008). Basic Facts about Magnesium Oxide and
Magnesium Hydroxide, http://www.magspecialties.com/students.htm (accessed July
2008).
MIT. Inventor of the Week: Henry Dow Bromine Extraction Process.
http://web.mit.edu/invent/iow/dow.html (accessed 2007).
5-34
-------
National Institutes of Health Haz-Map (NIH Haz-Map). Haz-Map: Occupational Exposure to
Hazardous Agents, http://hazmap.nlm.nih.gov (accessed 2007).
NIEHS (2001). Summary of Data for Chemical Selection: Magnesium Oxide. http://ntp-
server.niehs.nih.gov/ntp/htdocs/Chem_Background/ExSumPdf/Magnesiumoxide_508.pdf
(accessed July 2008).
Noonan, A. P.; Scherrer, S. C. Process for the manufacture of tetrabromobisphenol-A with co-
production of n-propyl bromide. [Online] U.S. Patent 6049014, April 11, 2000.
http://www.patentstorm.us/patents/6049014-description.html (accessed 2007).
OSW 1 (Office of Solid Waste). Electronics Waste Management in the United States: Approach
1. [Online] EPA: April 2007.
http://www.epa.gov/osw/conserve/materials/ecycling/docs/app-l.pdf (accessed 2007).
OSW 2 (Office of Solid Waste). Electronics Waste Management in the United States: Approach
2. [Online] EPA: April 2007.
http://www.epa.gov/osw/conserve/materials/ecycling/docs/app-2.pdf (accessed 2007).
Patent Storm, 2002. Polyphosphate salt of a 1, 3, 5-triazine compound with a high degree of
condensation, a process for its preparation and use as flame retardant in polymer
compositions. [Online], U.S. Patent Number 6369137, 2002.
http://www.patentstorm.us/patents/6369137-description.html (accessed 2007).
Plotkin, J. S. Direct Routes to Phenol. Chemistry.org: the Web site of the American Chemical
Society; 2006.
http://www.chemistry.org/portal/a/c/s/l/feature_pro.html?id=c373e908e6e847ac8f6al72
45d830100 (accessed 2007).
PSB Corporation 2006. 1 Science Park Drive, Singapore 118221. Unpublished results of testing
done to detect free TBBPA from extraction of prepreg sample Nelco N4000-6.
Sellstrom, U.; Jansson, B. Analysis of tetrabromobisphenol A in a product and environmental
samples. Chemosphere 1995, 31 (4), 3085-3092.
Shigeru, M. (Chemtura). Personal Communication. October, 2007.
Sjodin, A.; Patterson, D.; Bergman, A. A review on human exposure to brominated flame
retardants - particularly polybrominated diphenyl ethers. Environ. Intnatl. 2003, 29, 829-
839.
Tohka, Antti; Zevenhoven, Ron. Processing Wastes and Waste-derived Fuels Containing
Brominated Flame Retardants. Helsinki University of Technology Department of
Mechanical Engineering. April 2002.
5-35
-------
Umicore. Exploring Umicore Precious Metals Refining.
http://www.preciousmetals.umicore.com/publications/ (accessed 2007).
U.N. report. http://www.rrcap.unep.org/policy2/13-Annex%204a-e- wastes%20SEPD2.pdf:
http://news.yahoo.eom/s/nm/2007061 l/lf_nm/china_ewaste_dc (accessed 2007).
U.S. EPA (1999). Determining the adequacy of existing data. High Production Volume (HPV)
Challenge. Washington, DC: U.S. Environmental Protection Agency.
http://www.epa.gov/hpv/pubs/general/datadeqfn.pdf
U.S. EPA. Solders in Electronics: A Life-Cycle Assessment; EPA 744-R-05-001; August 2005.
U.S. EPA (2010). Bisphenol A Action Plan.
http://www.epa.gov/oppt/existingchemical s/pubs/actionplans/bpa_acti on_plan.pdf
(accessed September 2014).
USGS (2007). Silica Statistics and Information.
http://minerals.usgs.gov/minerals/pubs/commodity/silica (accessed October 2007).
USGS (2008). Mineral Commodity Summaries: Magnesium Compounds.
http://minerals.usgs.gov/minerals/pubs/commoditv/magnesium/mcs-2008-mgcom.pdf
(accessed July 2008).
Yoneda, Y.; Mizutani, D.; Cooray, N. A Highly Reliable Halogen-Free Dielectric for Build-up
Printed Circuit Boards. FUJITSUSci. Tech. J. 2002, 38 (1), 88-95.
York, The University of. Extraction of Bromine from Seawater.
http://www.vork. ac.uk/org/seg/test/ES/EXTRACTIONOFBROMINEFROMSEAWATE
R.ppt (accessed October 2007).
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6 Combustion and Pyrolysis Testing of FR-4 Laminates
6.1 Background and Objectives
End-of-life pathways for electronic waste (e-waste) include recycling via thermal or non-thermal
processing as well as landfilling. There has been increased demand to recycle e-waste for the
recovery of precious metals used in electronic products. Incineration is one popular and cost-
effective e-waste recycling technique. This type of thermal processing burns off the polymeric
components of the e-waste and leaves behind inorganic ash that can be further smelted and
refined to isolate reusable precious metals. When incineration is not conducted properly, the
combustion of polymeric components creates toxic by-products that can be released into the
environment. Unregulated incineration of electronics in developing countries has led to concerns
about exposure to such toxic by-products. This issue may be attributable to the exportation of
used electronics to developing countries that lack the capacity to manage them safely.
Little information exists about the combustion and pyrolysis products that could be formed
during thermal end-of-life scenarios of printed circuit boards (PCBs). The presence of flame
retardants in PCBs influences the emissions of the e-waste when burned. Flame retardants are
added to PCBs by manufacturers to help products to meet flammability standards. They protect
flammable polymers used in electronic products from potential ignition and help minimize fire
risk. The primary fire risk that flame retardants protect against in PCBs is that of an electrical
fault or short circuit ignition that can cause the polymers to ignite. An ignition site has the
potential to lead to flame spread across the PCB and can cause its electronic casing to also ignite,
and potentially propagate the flame into the electronic product's surrounding environment such
as a home, vehicle, or mass transport structure.
The stakeholders of this partnership decided that testing of Flame Resistant 4 (FR-4) laminates
and PCB components was warranted to learn more about potential by-products during thermal
end-of-life processes (e.g., open burning and incineration). While it would also be informative to
assess FR-4 laminates for teachability and offgassing during product use, these tests were not
possible with available resources. This chapter gives an overview of the rationale and methods
for combustion and pyrolysis testing of FR-4 laminates and PCB components. This section
provides background information and a rationale for why the combustion testing was conducted.
Section 6.2 offers an overview of Phase 1 of the combustion testing and information on how
Phase 1 informed Phase 2 of the testing. The section also describes the process of selecting
materials for Phase 2 and Section 6.3 summarizes Phase 2 conclusions, methods, and results.
The University of Dayton Research Institute (UDRI) led the combustion testing. UDRI has been
involved in studying thermal processes for the last three decades and has experience with the
flame retardants used in PCB manufacturing. The U.S. Environmental Protection Agency
(EPA)'s Office of Research and Development (ORD) supplemented UDRI's testing with sample
extraction and halogenated dioxins and furan analysis. The testing was completed in 2012.
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The following stakeholders funded the combustion testing and provided materials:
• Albemarle
• Boliden • IBM
• BSEF (Bromine Science and • ICL-IP America, Inc.
Environmental Forum) • Intel
• Chemtura • Isola
• Clariant • ITEQ
• Ciba Specialty Chemicals • Nabaltec
• Dell • Panasonic
• Environmental Monitoring • Seagate
Technologies, Inc. (EMT) • Sony
• Fujitsu-Siemens • Supresta
• Hewlett-Packard
The overall goal of this combustion testing project was to compare the combustion by-products
from FR-4 laminates and PCB components during potential thermal end-of-life processes,
including open burning and incineration. The results from this testing will help advance decision
making on the selection of flame-retardant materials and environmentally acceptable end-of-life
thermal disposal processes.
This study was conducted in two phases. Phase 1 testing was a pilot study designed to evaluate
the ability of proposed test methods to predict thermal degradation products of laminates. Phase
1 was also intended to help establish experimental methods and conditions for Phase 2 testing.
The goal of the Phase 2 testing was to understand the potential emissions of halogenated dioxins,
halogenated furans, and polyaromatic hydrocarbons (PAHs) of a standard tetrabromobisphenol A
(TBBPA) laminate compared to different halogen-free laminates in precious metal recovery
scenarios with and without typical circuit board components. A secondary goal of the Phase 2
testing was to expand cone calorimeter testing to other candidate laminates.
The laminates for testing in Phases 1 and 2 were selected to ensure a broad range of
compositions. In Phase 1, three laminates were tested: a standard TBBPA laminate (BFR), a
non-flame-retardant control laminate (NFR), and a halogen-free flame-retardant laminate
(PFR1). PFR1, which was provided by ISOLA, contains an additive blend of flame retardants
assessed in Chapter 4 of this report. At least one component of this blend contains phosphorus.
After Phase 1 was completed, UDRI reviewed the results with the partnership to determine the
best way to proceed with Phase 2. The three laminates from Phase 1 were selected for Phase 2
testing as well as one additional halogen-free flame-retardant laminate (PFR2) for a total of four
(see Table 6-2). PFR2, which was provided by Panasonic, contains a reactive phosphorus-based
flame retardant that is also assessed in Chapter 4 of this report. In Phase 2, PCBs were simulated
by combining the four laminates with homogeneous powders of components designed for
conventional boards. These component mixtures were provided by Seagate. Further details about
Phase 2 methods are located in Section 6.3.2 of this report. The suppliers of the phosphorus-
based flame retardant laminates preferred not to disclose the exact chemical identity of the flame
retardants in their laminates.
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6.2 Phase 1 Methods and Results
The methodology for the two phases of the combustion testing was developed through ongoing
collaboration among EPA, UDRI, and the stakeholders of this partnership. Phase 1 evaluated the
ability of proposed test methods to predict thermal decomposition products of a small number of
laminates (with TBBPA, an additive phosphorus flame retardant, or no flame retardant) and
established experimental methods and conditions. The laminates in Phase 1 were tested under a
number of different temperature and atmospheric conditions to predict combustion and pyrolysis
products that could occur across various end-of-life scenarios.
A more detailed description of the Phase 1 methods is available in the following documents
attached as appendices to this report:
• Appendix A - Yamada, Takahiro; Striebich, Richard. Open-burning, Smelting,
Incineration, Off-gassing of Printed Circuit Board Materials Phase I Flow Reactor
Experimental Results Final Report. Environmental Engineering Group, UDRI. August
11,2008.
This report summarizes flow reactor combustion tests conducted by UDRI. A
quartz reactor was used to conduct controlled pyrolysis and oxidation experiments
for the three different laminates at four different temperature/atmospheric
conditions. The results were analyzed using gas chromatography-mass
spectrometry (GC-MS). Aromatic hydrocarbons, specifically benzene, toluene,
naphthalene, and xylene, were the principal combustion by-products for all three
types of laminates. Bromophenol and dibromophenol were the brominated
organic products unique to the brominated flame-retardant laminates. No
phosphorus-containing organic compounds were observed for any of the
laminates. The primary by-products of the phosphorus-containing flame-retardant
laminates were various PAHs. The by-products of the phosphorus-containing
flame-retardants were very similar to the by-products of the non-flame-retardant
laminates.
• Appendix B - Sidhu, Sukh; Morgan, Alexander; Kahandawala, Moshan; Chauvin, Anne;
Gullett, Brian; Tabor, Dennis. Use of Cone Calorimeter to Estimate PCDD/Fs and
PBDD/Fs Emissions From Combustion of Circuit Board Laminates. US EPA and UDRI.
March 23, 2009.
This report by UDRI summarizes methods and emissions results from the
combustion of PCB laminates using cone calorimetry. The compounds examined
were polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and
polybrominated dibenzo-p-dioxins and furans (PBDD/Fs). The emissions samples
were analyzed using GC-MS. No chlorinated dioxin/furan congeners were
detected in the combustion exhaust of any of the three types of laminates.
Brominated dioxin/furan congeners were found in the brominated flame-retardant
laminates, informing the researchers of what compounds to look for in Phase 2 of
the combustion testing. The report also includes data on heat release and fire
behavior for each type of laminate.
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Laminates from the following companies were considered for testing under Phase 2.
• NanYa • ITEQ
• Hitachi • Nelco
• Isola • Shengyi
• TUC • Supresta
• Panasonic
A non-flame-retardant laminate provided by Isola was tested in both phases to serve as a control.
Data on the elemental composition of laminates used in Phase 1 from NanYa, Isola, Panasonic,
and ITEQ are reported in Appendix C and Appendix D.
Before the combustion and pyrolysis testing began in Phase 2, EPA ORD conducted X-ray
fluorescence (XRF) analysis of each laminate to determine its elemental composition. To
account for concerns among the partnership over the limitations of XRF analyses, follow-up
analyses were done by Dow and ICL Industrial Products (ICL-IP). Dow tested for bromine and
chlorine using neutron activation. ICL-IP tested for aluminum, calcium, magnesium, and
phosphorus using inductively coupled plasma-optical emission spectroscopy (ICP-OES),
bromine using titration, and chlorine using ion chromatography. Results from these analyses are
summarized in:
• Appendix C - U.S. EPA. Analysis of Circuit Board Samples by XRF. Original Report -
July 28, 2008. Revised Report - March 23, 2009. Prepared by Arcadis.
This report summarizes the elemental analysis of circuit board samples by U.S.
EPA ORD. XRF spectrometry was used to investigate the elemental makeup of
two sets of circuit board samples. In Phase 1 of the experiment, a non-flame-
retardant laminate, a bromine flame-retardant laminate, and a phosphorus flame-
retardant laminate were cored from a circuit board at random locations and
analyzed using XRF. The data from Phase 1 were of low quality so a second test
phase was conducted in an effort to achieve more reliable results. In Phase 2 of
the experiment, four halogen-free laminates were homogenized, powdered, and
pelletized prior to XRF analysis. The results of the XRF elemental analysis can be
found in Appendix D.
• Appendix D - U.S. EPA. Flame Retardant in Printed Circuit Boards Partnership: Short
Summary of Elemental Analyses. DRAFT. December 9, 2009.
This report summarizes the elemental analysis of circuit board samples by ICL-IP
and Dow. ICL-IP used ion chromatography to test for chlorine, titration to test for
bromine, and ICP-OES to test for aluminum, calcium, magnesium, and
phosphorus. Dow used neutron activation to test for bromine and chlorine. ICL-
IP's results suggest that the source of the aluminum, calcium, and magnesium
detected in the samples was from glass fiber or glass treatment and not from a
flame-retardant filler. Phosphorus was found in the largest quantities in the
phosphorus flame-retardant laminates. Bromine quantities were highest in the
6-4
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brominated flame-retardant laminate and existed in trace levels in the halogen-
free laminates. Chlorine values differed greatly from the XRF results. Similar
chlorine levels were detected in all laminates in small amounts along the order of
17100th to 1/10th of a percent by weight. This summary presents information on
the elemental analyses from the following memos:
ICL Industrial. JR 22 - Br and Cl Analysis in Copper Clad Laminates - part II.
February 12, 2009.
ICL-IP Analysis of Laminate Boards. Memo from Stephen Salmon. November
16, 2009.
Dow. Analysis of Chlorine and Bromine. November 2, 2009.
Table 6-1 summarizes the methodology for Phase 1 and Phase 2 of the combustion and pyrolysis
testing. This table can be used to compare the experiments conducted in both phases and
illustrates how the Phase 1 experiments influenced Phase 2.
Table 6-1. Summary of Combustion Testing Methodology
Phase 1
Phase 2
Goal:
To evaluate the suitability of test
methods to produce and measure
thermal degradation products of
laminates, and to establish experimental
methods/conditions for Phase 2 testing.
To understand the combustion by-
products and fire characteristics of a
standard TBBPA laminate compared
to different laminates containing
halogen-free flame retardants.
To evaluate the effects of circuit
board components in various
precious metal recovery scenarios.
To expand cone calorimeter testing
to other candidate laminates.
Test Methods:
Thermogravimetric analysis to
determine pyrolysis temperatures for
establishing experimental methods for
Phase 2
(performed by UDRI)
Pyrolysis/quartz tube reactor system and
cone calorimeter to evaluate the
suitability of test methods to produce
and measure thermal degradation
products
(performed by UDRI)
XRF to determine elemental
composition for establishing
experimental methods for Phase 2
(performed by EPA ORD)
Neutron activation to determine
Cone calorimeter
6-5
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Phase 1
elemental composition for establishing
experimental methods for Phase 2
(performed by Dow)
ICP-OES, titration, and ion
chromatography to determine elemental
composition for establishing
experimental methods for Phase 2
(performed by ICL-IP)
Phase 2
Test Materials:
TBBPA laminate (BFR)
Non-flame-retardant laminate (NFR)
Phosphorus-based flame-retardant
laminate (PFR1)
(Several different laminates of each type
were analyzed to inform the selection of
Phase 2 laminates)
TBBPA laminate (BFR)
Non-flame-retardant laminate (NFR)
Phosphorus-based flame-retardant
laminate (PFR1)
Phosphorus-based flame-retardant
laminate (PFR2)
Plus 6 combinations of components
and laminates
Size of Sample
Material:
For quartz tube: 1.5-2 mm x 10 mm
For cone calorimeter: -100 cm2 square
pieces up to 50 mm thick
For cone calorimeter: -100 cm
square pieces approximately 50 mm
thick
Test Conditions:
For quartz tube: 7 different
temperature/atmosphere conditions
300°C & 0% O2
300°C&21%O2
700°C & 0% O2
700°C & 10% O2
700°C&21%O2
900°C & 0% O2
900°C&21%O2
For cone calorimeter: Moderately high
power (50 kW/m2) and air atmosphere
Moderately high power (50 kW/m2)
and air atmosphere; and highest
possible power (100 kW/m2) and air
atmosphere
Analytical
Method:
GC-MS analysis for dioxins/furans
(performed by EPA ORD)
GC-MS analysis for PAHs
(performed by UDRI)
Cone calorimetry data on CO, CO2, PM,
smoke, and heat release
GC-MS analysis for dioxins/furans
(performed by EPA ORD)
GC-MS analysis for PAHs and
organophosphorus compounds
(performed by UDRI)
Cone calorimetry data on CO, CO2,
PM, smoke, and heat release
6.3 Phase 2
Phase 2 identified the by-products of four laminates alone and with PCB components added
through use of cone calorimetry and GC-MS analysis. Phase 1 results informed the methodology
6-6
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and experimental conditions used in Phase 2 of the combustion testing. The research conducted
in Phase 2 was also influenced by available funding, stakeholder input, and difficulties
associated with novel equipment design. This section will summarize the conclusions, methods,
and results of the Phase 2 testing. The full Phase 2 report is available in:
• Appendix E - University of Dayton Research Institute. Use of Cone Calorimeter to
Identify Selected Polyhalogenated Dibenzo-P-Dioxins/Furans and Polyaromatic
Hydrocarbon Emissions from the Combustion of Circuit Board Laminates. October 22,
2013.
The sample abbreviations used and order of the data presented in the figures in Section 6.3 of
this report differ from those in Appendix E (full Phase 2 report). These minor changes are
intended to increase the clarity of the Phase 2 findings for readers.
6.3.1 Phase 2 Conclusions
This section summarizes the main conclusions from Phase 2 testing. The methods used in the
Phase 2 combustion testing are described in Section 6.3.2 followed by detailed results in Section
6.3.3.
Table 6-2 presents the sample combinations of laminates and components burned during Phase 2
testing, as well as the combustion scenarios (open burn and incineration) and the combustion
emissions tested. A summary of the Phase 2 results is provided in Table 6-3 and Table 6-4 at the
end of this section.
Table 6-2. Overview of Phase 2 Testing Methodology and Associated Abbreviations
Laminates Burned
Laminate/Component
Combinations Burned
Scenarios (Heat Flux)
Analytes Tested
TBBPA laminate (BFR)
Non-flame-retardant laminate (NFR)
Phosphorus-based flame-retardant laminate (PFR1)
Phosphorus-based flame-retardant laminate (PFR2)
BFR + standard halogen components (BFR + SH)
BFR + low-halogen components (BFR + LH)
PFR1 + standard halogen components (PFR1 + SH)
PFR1 + low-halogen components (PFR1 + LH)
PFR2 + standard halogen components (PFR2 + SH)
PFR2 + low-halogen components (PFR2 + LH)
Open Burn (50 kW/m2) (Laminate abbreviation-50)
Incineration (100 kW/m2) (Laminate abbreviation-00)
Polybrominated dibenzo-p-dioxins/furans (PBDD/Fs)
Polyaromatic hydrocarbons (PAHs)
Screening for organophosphorus degradation products
As presented in Table 6-3, PBDD/F analysis was only done for the laminate containing TBBPA
because results from the Phase 1 elemental analyses revealed that PFR1 and PFR2 contained low
levels of bromine (<0.04 percent by weight) and therefore would not generate detectable levels
of PBDD/Fs. In comparison, the elemental analyses of BFR revealed levels of bromine between
6-7
-------
6.1 and 8.1 percent by weight. Detectable levels of PBDD/Fs were emitted for all BFR laminates
combusted. For the BFR laminate without components, higher levels of PBDD/Fs were
generated in open burn conditions (3.04 ng/g) compared to incineration conditions (2.20 ng/g).
PBDD/Fs were detected in the BFR laminates containing low-halogen components (1.88 ng/g)
but could not be quantitated in the samples containing standard halogen components due to
significant interference with the standard.
Although there was an attempt to measure chlorinated dioxins and furan emissions for the BFR
laminates, the inability to detect the pre-sampling surrogate for some of the samples did not
allow for effective quantification of the PCDD/Fs. It should be noted that detectable levels of
PCDD/Fs were not found in any of the laminates when these compounds were quantified in
Phase 1.
As shown in Table 6-4, PAHs were emitted by all materials. Of the laminates without
components, BFRs emitted the highest levels of PAHs in both open burn (5.22 g/kg) and
incineration (5.08 g/kg) conditions. The NFR in open burn conditions had the lowest levels of
PAH emissions of the laminates without components (0.624 g/kg). PFR1 without components
had the lowest levels among laminates in incineration conditions (1.51 g/kg). Of the samples
with standard halogen components in open burn conditions, BFR generated the greatest amount
of PAHs (3.93 g/kg), followed by PFR2 (2.24 g/kg), and PFR1 (2.04 g/kg); a similar emissions
trend was observed for the samples containing low-halogen components.
In addition to the PBDD/F and PAH analyses, data on smoke, particulate matter, CO and CO2
releases, and heat release were also collected during Phase 2. Smoke release was greatest for
BFRs both with and without components. Particulate matter values for laminates without
components were highest for PFR1 in open burn conditions. With the exception of the NFR
laminate, samples without components emitted lower levels of particulate matter when
combusted in incineration conditions compared to open burn conditions. The NFR laminates
without components generated the lowest amount of particulate matter in both combustion
scenarios compared to the other samples. Of the samples containing standard halogen
components, BFR laminates emitted the greatest levels of particulate matter and PFR2 laminates
generated the least; this particulate matter emissions trend was also observed in samples
containing low-halogen components. However, particulate matter trends did not always align
with smoke release emissions. While differences in CO release between samples were negligible,
CO2 emissions varied depending on laminate type.
Table 6-3. Summary of Phase 2 PBDD/Fs Results
Sample
BFR- 100
BFR-50
BFR + SH-50
BFR + LH -50
PBDD/Fs
Present
Present
Not quantified
Present
Quantity of PBDD/Fs detected (ng/g)
2.20
3.04
N/A
1.88
Sample size: n=2. PBDD/Fs were only tested for the brominated laminates.
6-8
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Table 6-4. Summary of Phase 2 PAH Results
Sample
Quantity of PAHs detected (g/kg)
Incineration (100 kW/m2)
BFR-100
PFR1-100
NFR-100
5.08
1.51
1.95
Open burn (50 kW/m2)
BFR-50
PFR1-50*
PFR2-50
NFR-50*
5.22
1.74
2.93
0.624
Open burn (50 kW/m ) with standard halogen components
BFR + SH-50
PFR1 + SH-50
PFR2 + SH-50
3.93
2.04
2.24
Open burn (50 kW/m ) with low-halogen components
BFR + LH-50
PFR1 + LH-50
PFR2 + LH-50
3.69
1.75
2.11
Sample size: n=2 except for samples with asterisk for which n=l.
6.3.2 Phase 2 Methods
The combustion testing for Phase 2 was possible through the collaboration of many entities
(Figure 6-1). Isola prepared the copper clad laminates in accordance with the laminate
preparation procedures established in Phase 1 of the testing. A copper surface area of-33
percent was pressed on each laminate to simulate real-world conditions of PCBs.
Figure 6-1. Overview of Workflow for Combustion Testing and Analysis
Panasonic & Isola
Laminate
contribution
Seagate
Component mixture
preparation
Isola
Laminate
preparation
EMT
Component mixture
grinding
UDRI
Combustion
testing
UDRI
Phosphorus and
PAH analysis
RTF
• Byproduct
extraction
• Dioxin/furan
analysis
Seagate prepared the circuit board components. The component mixture simulated materials
found in standard disk drive boards and included integrated circuits, resistors, capacitors,
connectors (main source of plastic housing), shock sensors, and accelerometers. Both a low-
halogen component mixture and a standard halogen component mixture were prepared by
6-9
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Seagate. The partnership agreed to grind up the components prior to combustion testing to
provide a more inclusive sample, have a more uniform sample preparation, and have more
reliable results. EMT ground up the components and sent them to UDRI for combustion testing.
UDRI led the Phase 2 combustion testing. The laminate samples were tested under conditions
mimicking open burning and incineration operations. Gases from combustion were collected in
filters and polyurethane foam (PUF) cartridges contained in the cone calorimeter exhaust duct.
The PUFs were cleaned and prepared with a pre-sampling spike of PBDD/F and PCDD/F quality
controls to confirm that gases were being retained in the collection system and not lost through
handling and extraction processes. A modified cone calorimeter was used to measure the
emissions of particulate matter, CO, CC>2, and smoke from the samples and collect the
combustion gases because it could mimic burning conditions of interest while providing
quantitative emission information from complex circuit board samples. Heat release information
and total mass burned were also measured; heat release information can reveal a material's
flammability performance, while the total mass of each sample burned is used to determine
emission factors.
The original experimental plan included a third combustion scenario for low-oxygen combustion
to mimic smelting conditions. When UDRI initially burned samples under the simulated smelting
conditions, combustion gases escaped from the top of the cone calorimeter apparatus. The
outflow of these gases could have led to more complete combustion when exposed to more
oxygen, which would have yielded inaccurate results. As a result, UDRI and the partnership
collectively decided to exclude the low-oxygen combustion test condition from the study due to
time and budget needed to modify the cone calorimeter system.
After the laminates were burned by UDRI, the PUFs and filters were shipped to EPA ORD for
extraction, cleanup, and fractionation. Prior to extraction, the samples were spiked with internal
standard mixtures for quality control purposes. The internal standards allow quantification of the
native targets in the sample as well as help determine the overall method efficiency or
"recovery" of the target. The dioxin and furan analysis carried out in Phase 2 focused on 2,3,7,8-
substituted congeners of PCDD/Fs and their brominated counterparts. The target analytes
included 17 PCDD/F congeners and only 13 PBDD/Fs congeners due to limited availability of
commercial standards. Quality control for the dioxin and furan analysis was monitored using
labeled pre-sampling (surrogate standards), pre-extraction (internal standards), and pre-injection
(recovery standards) spiking solutions.
The PUFs and filters were extracted for PBDD/Fs using sequential Soxhlet extraction. The
sequential Soxhlet extraction of the PUFs and filters required a 16-hour extraction with
methylene chloride followed by another 16-hour extraction using toluene. The sampling train
was also rinsed first with methanol, then methylene chloride, and lastly toluene after each run to
collect any by-products that were not collected in the PUFs and filters. Once it was discovered
that less than ten percent of the PBDD/Fs were found in the sample rinses, extraction for
PBDD/Fs was only done for the PUFs and filters and the sampling train rinses were kept at
UDRI for PAH analysis.
6-10
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One portion of the Soxhlet-extracted samples was cleaned and fractionated for PBDD/F analysis
at EPA. Clean-up of the extracts was required and done by washing the samples through a
sequence of acidic and multilayer silica, carbon, and alumina columns. This multi-column liquid
chromatography clean-up system was performed to ensure that combustion-related matrices
would not interfere with the results of the analysis of the target compounds. EPA then analyzed
the extracts using GC-MS for target PCDD/Fs and PBDD/Fs.
Another portion of the Soxhlet-extracted samples was sent back to UDRI for analysis of PAHs
and organophosphorus compounds. (The extracts for PAH analysis did not undergo the same
cleanup procedure as the extracts for dioxin and furan analysis.) The sampling train rinses were
also used in the measurement of PAHs by UDRI. Liquid-liquid extraction using the methylene
chloride rinse on the methanol rinse was performed. The four sample media tested for the
presence of PAHs were: the methylene chloride from the methanol and methylene chloride
rinses, the toluene rinse, the methylene chloride Soxhlet extraction of the PUF and filter, and the
toluene Soxhlet extraction of the PUF and filter. UDRI used GC-MS to analyze the extracts for
target PAHs and organophosphorus compounds. The PAHs targeted in the analysis were the 16
EPA priority PAHs. The organophosphorus analysis was conducted by doing a library scan of
the chromatograms from the PAH analysis. Organophosphorus compounds were not quantified
because the internal calibration standards necessary to conduct the analysis have not yet been
commercially established.
Detailed information about the methods used for Phase 2 combustion testing can be found in
Appendix E of this report.
6.3.3 Phase 2 Results
Halogenated Dioxin and Furan Analysis
Halogenated dioxins and furans were only analyzed for the samples containing BFRs. These
samples were tested without components at incineration conditions, and both with and without
components at open burn conditions. Although UDRI's combustion testing generated 42 samples
for analysis, only a subset of samples were selected for halogenated dioxin and furan testing.
Nine samples were selected for PCDD/Fs analysis, and 14 samples selected for PBDD/Fs
analysis. As explained in Section 6.3.1, lack of detection of the pre-sampling quality control
spike prevented the analysis of PCDD/F emissions.
Of the 14 samples chosen for PBDD/F analysis, testing was not carried out for the two samples
intended to be burned under simulated smelting conditions (low oxygen). As explained in
Section 6.3.2, all low-oxygen tests were excluded from this experiment due to the inability to
yield reliable results. Of the 12 samples left to be analyzed after excluding the low-oxygen tests,
six blanks were added for a total of 18 samples to be analyzed for PBDD/Fs. PBDD/F emissions
could not be quantified for the six BFR-SH samples due to significant interference that caused
the internal standards to be unusable. After excluding the six BFR-SH samples, PBDD/Fs were
able to be quantified in 12 samples: 2 BFR-50, 2 BFR + LH, 2 BFR-100, and 6 blanks. Figure
6-2 presents the order of the blanks and brominated laminates combusted in the cone calorimeter
that were tested for PBDD/Fs, but does not include samples not tested for PBDD/Fs that may
6-11
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have been combusted within this sequence of 12 samples; other samples not analyzed for
PBDD/Fs may have been combusted within this scheme.
Figure 6-2. Combustion sequence for samples tested for PBDD/Fs
Blank 2 —>- Blank 3 • »• BFR-100 —* BFR-100 ^* Blank 4 n-BFR+LH-50:—»-BFR+LH-50r~>- Blanks i-» Blank 6
PBDD/Fs were detected and quantified in all six BFR samples (Figure 6-3); five of the six blanks
had significantly lower levels of PBDD/Fs compared to the laminate samples. For example, the
detection of 1,2,3,4,6,7,8 - HpBDF ranged from 4 to 9 ng/train for the six BFR laminate samples
compared to not detected to 0.3 ng/train in all but the first combustion blank.
PBDD/Fs were detected in the first blank at levels as high as 11.7 ng/train. The subsequent
samples are still considered valid because the congener pattern detected in the first blank differed
greatly from the congener patterns detected in the subsequent samples and blanks. The first blank
had large amounts of HpBDF and OBDF compared to the other samples and blanks analyzed for
PBDD/Fs. The levels of HpBDF and OBDF detected from the combustion of the two laminate
samples following the first blank (Figure 6-2) were about half of that detected in the first blank.
The levels of tetra- through hexaBDF detected in the two laminate samples following the first
blank were much higher than the levels detected in the first blank. Therefore, it is unlikely that
laminate samples tested after the first blank and before the second blank were impacted by the
tetra- through hexaBDF levels in the first blank. A conservative interpretation of the PBDD/F
data for the first three tests would be to dismiss only the HpBDF and OBDF values for the first
two laminates tested. The second blank tested had very low levels of HpBDF and OBDF
detected. Therefore, no concerns about the levels of PBDD/Fs detected were raised by the
investigators for the samples following the second blank. Although the ductwork and sampling
train were cleaned, the detection of low concentrations of PBDD/Fs in the combustion blanks
may be due to cross-contamination in the cone calorimeter duct. This cross-contamination is
likely an outcome of the complexity of the cone calorimeter system and the reuse of many parts
to create it. The difference in the amount of PBDD/Fs detected between the combustion blank
samples and the BFR samples was as large as a factor of 100.
Higher chlorine levels were detected in the standard halogen components compared to the low-
halogen components based on elemental analyses of the component mixtures (Appendix E). The
difference in the levels of certain elements and molecules in the component mixtures may impact
some endpoints including the production of chlorinated dioxins and furans, which could not be
quantified in this study.
Figure 6-3 presents the sum of the target PBDD/F analytes emitted from the cone calorimeter
experiments.
6-12
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Figure 6-3. PBDD/Fs Emission Factors Plot
PBDD/Fs Emission Factors
3.50E+00
3.00E+00
5.00E-01
O.OOE+00
1,2,3,4,6,7,8,9-OBDF
1,2,3,4,6,7,8 - HpBDF
1,2,3,4,7,8 - HxBDF
2,3,4,7,8 - PeBDF
1,2,3,7,8 - PeBDF
2,3,7,8-TBDF
1,2,3,4,6,7,8,9-OBDD
1,2,3,4,6,7,8-HpBDD
1,2,3,7,8,9-HxBDD
1,2,3,4,7,8 + 1,2,3,6,7,8 - HxBDD
1,2,3,7,8-PeBDD
2,3,7,8-TBDD
Sample Description
The BFR + SHs could not be quantitated due to significant interference with the standard.
Data are an average of results from two tests.
Polyaromatic Hydrocarbon Analysis
PAHs were detected and quantified in all samples. EPA's 16 priority PAHs were the target
compounds for this analysis. It should be noted that PAH analysis from the PUF sampling was
not expected to capture the light PAHs (i.e., PAHs containing <4 fused benzene rings).
Therefore, the levels of light PAHs could be under reported. Figure 6-4 presents the PAH
emission factors for samples without components. Of these samples, the BFRs combusted at both
heat fluxes had the highest total PAH emissions - about twice the emissions of the non-
brominated laminates. The NFR in open burn conditions had the lowest PAH emissions of all
sample types. PFR2 was only tested in open burn conditions.
Figure 6-5 presents the PAH emission factors for samples with components. BFR laminates
emitted the highest levels of PAHs among the different flame-retardant laminates with
components. PAH emissions were similar between standard halogen and low-halogen
components when compared within the same flame retardant laminate.
The flame retardant chemistry of each laminate type helps to characterize the PAH emission
factor trends. TBBPA is a flame retardant that inhibits combustion in the vapor phase, which
therefore yields more incomplete combustion products. On the other hand, the flame retardant
systems used by PFR1 and PFR2 are phosphorus-based, which uses a condensed phase
mechanism to form a char on the sample's surface. The char formation binds up potential PAH
structures, resulting in fewer incomplete combustion products compared to the mechanism
employed by TBBPA. Effects of flame retardant mechanisms on PAH emissions are generally
reflected in Figure 6-4 and Figure 6-5.
6-13
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Figure 6-4. PAH Emission Factors Plotted for Naphthalene and Higher Molecular Weight (MW) PAHs
Detected from the EPA List of 16* Priority PAHs in Samples without Components
6.00E+00
5.00E+00
4.00E+00
3.00E+00
2.00E+00
l.OOE+00
O.OOE+00
PAH Emission Factors
Sample Description
Benzo[g,h,i]perylene
Dibenz[a,h]anthracene
lndeno[l,2,3-cd]pyrene
Benzo[a]pyrene
Benzo[b+k]fluoranthene
Chrysene
I Benz[a]anthracene
Pyrene
I Fluoranthene
I Anthracene
Phenanthrene
I Fluorene
I Acenaphthene
Acenaphthylene
I Naphthalene
*Benzo[b]fluoranthene and benzo[k]fluoranthene are reported together
*Based on a single test; data without asterisks are an average of results from two tests.
Figure 6-5. PAH Emission Factors Plotted for Naphthalene and Higher MW PAHs Detected from the EPA
List of 16t Priority PAHs in Samples with Components
6.00E+00
5.00E+00
4.00E+00
f 3.00E+00
1
2.00E+00
l.OOE+00
O.OOE+00
PAH Emission Factors
Sample Description
Benzotg^ijperylene
Dibenz[a,h]anthracene
lndeno[l,2,3-cd]pyrene
Benzo[a]pyrene
Benzo[b+k]fluoranthene
Chrysene
Benz[a]anthracene
Pyrene
Fluoranthene
Anthracene
Phenanthrene
Fluorene
Acenaphthene
Acenaphthylene
Naphthalene
*Benzo[b]fluoranthene and benzo[k]fluoranthene are reported together
6-14
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Data are an average of results from two tests.
Figure 6-6 presents the total emissions for the known carcinogenic PAHs for the samples without
components and Figure 6-7 presents the total emissions for the known carcinogenic PAHs for
samples with components. The emissions trends for the known carcinogenic PAHs for samples
without components in Figure 6-6 follow similar emissions trends to the 16 priority PAHs
without components presented in Figure 6-4; parallel trends are also observed between the
samples with components presented in Figure 6-7 and Figure 6-5. Carcinogenic PAH emissions
for samples without components were greatest for the BFR laminates in both combustion
scenarios, with emissions being slightly higher in open burn conditions than in incineration
conditions. Of the halogen-free flame-retardant laminates without components, PFR1 had lower
carcinogenic PAH emissions compared to PFR2. For all flame-retardant laminates (BFR, PFR1,
PFR2) without components, carcinogenic PAH emissions were greater in open burn conditions
compared to incineration conditions. The NFR laminates without components had the lowest
carcinogenic PAH emissions of all samples. Of the samples with components, BFR laminates
with standard and low-halogen components had the highest carcinogenic PAH emissions -
about twice the emissions of the PFRs. Samples with standard halogen components emitted only
slightly higher levels of carcinogenic PAHs for all laminate types (BFR, PFR1, PFR2) compared
to low-halogen components.
Figure 6-6. Emission Factors of Carcinogenic PAHs from the EPA List of 16* Priority PAHs in Samples
without Components
Carcinogenic PAH Emission Factors
8.00E-01
7.00E-01
Benzo[g,h,i]perylene
Dibenz[a,h]anthracene
lndeno[l,2,3-cd]pyrene
Benzo[a]pyrene
Benzo[b+k]fluoranthene
Chrysene
Benz[a]anthracene
O.OOE+00
Sample Description
*Benzo[b]fluoranthene and benzo[k]fruoranthene are reported together
*Based on a single test; data without asterisks are an average of results from two tests.
6-15
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Figure 6-7. Emission Factors of Carcinogenic PAHs from the EPA List of 16t Priority PAHs in Samples with
Components
Carcinogenic PAH Emission Factors
8.00E-01
7.00E-01
6.00E-01
„,- 5.00E-01
I
." 4.00E-01
c
01
M
C 3.00E-01
2.00E-01
l.OOE-01
O.OOE+00
Benzo[g,hj]perylene
Dibenz[a,h]anthracene
lndeno[l,2,3-cd]pyrene
Benzo[a]pyrene
Benzo[b+k]fluoranthene
Chrysene
• Benz[a]anthracene
Sample Description
*Benzo[b]fluoranthene and benzo[k]fluoranthene are reported together
Data are an average of results from two tests.
Because PCDD/Fs were unable to be quantified, attempts were made to determine the presence
of other chlorinated benzenes and phenols known to be PCDD/F precursors. No chlorinated
benzenes or phenols were detected at the concentrations analyzed in the PAH analysis. Although
the absence of PCDD/F precursors in the PAH analysis may indicate that PCDD/Fs would not
have been created under the combustion conditions tested in this study, this is merely a
hypothesis.
Organophosphorus Analysis
Because PFR1 and PFR2 were phosphorus-based, UDRI conducted a spectral library scan for
Organophosphorus compounds in the laminate emissions. The human health and environmental
impacts of exposure to these compounds were not assessed and are outside the scope of this
report. It was assumed that the detection of Organophosphorus compounds would indicate the
presence of a vapor phase flame retardant, while the detection of no Organophosphorus emissions
would indicate the presence of a condensed phase flame retardant. Organophosphorus compound
levels were unable to be quantified because the internal calibration standards vital to the quality
control of the analysis have not yet been commercially developed. For this reason, the
Organophosphorus analysis in this report is limited strictly to a spectral library match.
Organophosphorus compounds were detected in all samples (Table 6-5). However, different
compounds were detected from the repeat burn of the same laminate type. Some of the
compounds detected are likely to be products of the flame retardant mechanism while others may
6-16
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be post-combustion reaction products or products of reactions between either PFR1 or PFR2 and
the circuit board components. Compounds containing silicon, for example, were likely the result
of reactions between e-glass in the component mixture and the flame retardant. Compounds
containing phosphonic or phosphinic acids are likely the decomposition products of phosphorus
flame retardants.
Table 6-5. Organophosphorus Compounds Detected
Laminate
Description
BFR -100
BFR -100
BFR -50
BFR -50
BFR + SH -50
BFR + SH -50
PFR1 +SH-50
PFR2 + SH -50
BFR + LH-50
BFR + LH-50
PFR1 + LH-50
PFR1 + LH-50
PFR2 + LH-50
Organophosphorus Compounds Detected
Ethylphosphonic acid, bis(tert-butyldimethylsilyl) ester
Methylenebis(phosphonic acid), tetrakis(3-hexenyl) ester
1 -Ethyl- 1 -hydridotetrachlorocyclotriphosphazene
Silanol, trimethyl-, pyrophosphate
Phosphonic acid, methylenebis-, tetrakis(trimethylsilyl) ester
O,O'-(2,2'-Biphenylylene)thiophosphoric acid
Bis(4-methoxyphenyl)phosphinic acid
Phosphonic acid, phenyl-, diethyl ester
Phosphorane, 1 lH-benzo[a]fluoren-l-ylidenetriphenyl-
l-Phosphacyclopent-2-ene, 1-methyl -5-methylene-2,3-diphenyl-
Silanol, trimethyl-, pyrophosphate(4:l)
l-Phosphacyclopent-2-ene, 1-methyl -5-methylene-2,3-diphenyl-
4-Phosphaspiro[2.4]hept-5-ene, 4-methyl-5,6-diphenyl-
Bis(4-methoxyphenyl)phosphinic acid
l-Phosphacyclopent-2-ene, 1-methyl -5-methylene-2,3-diphenyl-
(2-Bromo-3 -methylphenyl) diphenylphosphine
Phosphine imide, P,P,P-triphenyl-
Phosphine imide, P,P,P-triphenyl-
Area %
8.33
0.29
0.04
0.51
0.17
0.38
0.10
0.25
0.43
0.53
0.08
0.61
0.15
0.15
0.23
0.34
0.30
0.21
Smoke Release Analysis
Total smoke release for samples without components is presented in Figure 6-8. BFRs had the
highest total smoke release among all samples without components, with releases being slightly
greater in open burn conditions than in incineration conditions. The higher smoke release for the
brominated flame-retardant laminate is likely due to its flame retardant mechanism that works by
inhibiting vapor phase combustion, which creates more smoke. Total smoke release for the BFRs
was less in incineration conditions compared to open burn conditions. PFR1 and PFR2 had lower
total smoke release than the BFRs but only slightly higher total smoke release than the NFRs. It
is likely that less smoke was emitted from PFR1 and PFR2 than the BFRs due to differences in
the way each type of flame retardant works. PFR1 and PFR2 use a condensed phase char
formation mechanism, which creates less smoke than a vapor phase mechanism. The char
formation mechanism may also give insight into why an increase in PFRl's smoke release was
observed when the heat flux was increased. The PAHs in the char of PFR1 and PFR2 may have
become pyrolyzed when the heat flux rose, causing soot and condensed phase soot precursors to
form. However, interpretations should consider the fact that the increase in smoke release is
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within the percent error of the smoke measurement device (±10 percent). The NFRs had the
lowest total smoke release overall, but was within the percent error of PFR1 and PFR2.
Total smoke release for samples with components is presented in Figure 6-9. BFRs had the
highest total smoke release among all samples with components, with releases being greater in
the presence of standard halogen components compared to low-halogen components. In fact,
higher smoke releases were observed for all laminate types (BFR, PFR1, PFR2) in the presence
of standard halogen components compared to low-halogen components. While smoke data are
important for determining incomplete combustion, smoke release is measured by light
obscuration. For this reason, smoke release measurements cannot be directly correlated to the
other emissions of concern investigated in this combustion testing project.
Figure 6-8. Total Smoke Release Plot for Samples without Components
Total Smoke Release
800.00
700.00
100.00
0.00
~Jo0
•Sn
Sample Description
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Figure 6-9. Total Smoke Release Plot for Samples with Components
Total Smoke Release
800.00
100.00
0.00
'-So
"-So
Sample Description
*V,
Particulate Matter Release Analysis
The particulate matter results do not directly correlate with smoke release. For example, total
smoke release was greatest for the samples containing the BFRs, while particulate matter was not
always highest for the samples containing the BFRs. Differences between smoke release and
particulate matter may be explained by smoke's chemical complexity; it is a substance that is
composed of solid particles, liquid vapors, and gases. It is possible that the organic vapors
released from the combustion of the BFRs were not captured by the filters measuring particulate
matter but successfully obscured the light in the smoke release measurements.
Particulate matter emissions for samples without components are presented in Figure 6-10.
Particulate matter emissions were higher in open burn conditions for all laminate types except
the NFR. PFR1 in open burn conditions had the greatest particulate matter releases of all
laminate types without components and were higher than the BFRs combusted in the same
atmospheric conditions. The char phase flame retardancy mechanism can account for the higher
particulate matter release; higher levels of particulate matter emissions may be the result of the
pyrolyzation of the charred and cross-linked polymer components. Figure 6-11 presents
particulate matter emissions for samples with components. Differences between BFR and PFR
for particulate matter emissions appear negligible for the three laminate types with components.
Particulate matter emissions were greater in the presence of standard halogen components than
low-halogen components for all laminate types.
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Figure 6-10. Participate Matter Emission Factors for Samples without Components
Particulate Matter Emission Factors
40.00
35.00
30.00
25.00
S
"SB
S
Q.
20.00
15.00
10.00
5.00
0.00
"3?..
Sample Description
Figure 6-11. Particulate Matter Emission Factors for Samples with Components
Particulate Matter Emission Factors
40.00
35.00
5.00
0.00
Sample Description
CO/COi Release Analysis
Figure 6-12 presents CO/CO2 emissions for samples without components. In both combustion
scenarios, BFRs without components had the lowest CC>2 emissions of all laminate types. CC>2
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emissions were also lowest for BFRs of the samples with components presented in Figure 6-13.
The comparatively lower CO2 emissions for the BFR laminates is likely due to the inhibition of
total combustion by bromine, which prevents carbon from converting to CO2. However, a
decrease in CO2 emissions is not always accompanied by an increase in CO release as evidenced
by the emissions trends for samples with (Figure 6-13) and without (Figure 6-12) components.
PFR1 and PFR2 have CO emissions similar to the BFRs but higher CO2 emissions. More CO2
may be emitted when phosphorus-based flame retardants form char because less carbon is
combusted. Halogenated flame retardants, in contrast, interfere with combustion in the vapor
phase, leading to incomplete combustion and lower CO2 yields. CO2 yields were highest for the
NFRs but their CO emissions were similar to or higher than the other laminate types in open
burn conditions. While potential carbon in flame-retardant laminate systems is present as PAHs
and soot, it is partly oxidized in the non-flame-retardant systems. CO and CO2 emissions are best
explained by combustion chemistry, flame retardant type and the presence of components.
Figure 6-12. CO/CO2 Emission Factors Plot for Samples without Components
Post Ignition CO/CO, Emission Factors
J00
J0O -u
Sample Description
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Figure 6-13. CO/CO2 Emission Factors Plot for Samples with Components
Post Ignition CO/CO, Emission Factors
Sample Description
Heat Release Results
Although flammability and fire safety were not the main focus of Phase 2 combustion testing,
heat release information for each sample was captured using the cone calorimeter. Detailed
information on heat release results can be found in Appendix E of this report. The heat release
information gathered in this combustion testing study should not be used to infer the fire safety
of the product, as each fire test used for regulating flame retardant materials is tailored for a
specific fire risk scenario. Therefore, the cone calorimeter data in this study are best used to
understand how much heat an object gives off when burned in a situation where it is well
ventilated and a robust heat source is present.
In open burn scenarios, the flame-retardant laminates had lower peak heat releases compared to
the laminates that did not contain flame retardants. Components generally increased total heat
release, but had differing effects on peak heat release. In incineration conditions, the BFRs
lowered heat release compared to the NFRs. PFR1 emitted heat at levels about equal or slightly
higher than the NFRs; heat release was not measured for PFR2 in incineration conditions.
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7 Considerations for Selecting Flame Retardants
Selecting an alternative chemical flame retardant involves considering a range of factors. Design
for the Environment (DfE) chemical alternatives assessments provide extensive information on
chemical hazards and provide a more general discussion of other factors relevant to substitution
decisions, such as: use information and exposure and life-cycle considerations. Decision-makers
will likely supplement the human health and environmental information provided in this report
with information on cost and performance that may vary depending on the supplier, the materials
involved, and the intended application. Alternative flame retardants must not only have a
favorable environmental profile, but also must provide satisfactory (or superior) fire safety, have
an acceptable cost, and attain the appropriate balance of properties (e.g., mechanical, thermal,
aesthetic) in the final product. Users of information in this report may wish to contact the
manufacturers of alternative flame retardants for engineering assistance in designing their
products with the alternatives.
This chapter outlines attributes that are appropriate for a decision maker to consider in choosing
an alternative to tetrabromobisphenol A (TBBPA). The chapter begins by describing five general
attributes evaluated in this assessment that can inform decision-making about chemical hazards:
(1) human health, (2) ecotoxicity, (3) persistence, (4) bioaccumulation potential, and (5)
exposure potential. The chapter gives special attention to discussion of data gaps in the full
characterization of chemicals included in this assessment. The chapter also includes information
on the social, performance, and economic considerations that may affect substitution and the
chapter concludes by providing additional resources related to state, federal, and international
regulations.
The scope of this assessment was focused on the human health and environmental hazards of
potential flame retardant substitutes. The report does not include a review or analysis of any
additional life-cycle impacts, such as energy and water consumption or global warming potential,
associated with any of the baseline or alternative chemicals, or the materials in which they are
used. If selection of an alternative flame retardant requires significant material or process
changes, relevant life-cycle analyses can be applied to the potentially viable alternatives
identified through this hazard-based alternatives assessment, and to the materials in which they
are used. Manufacturers may also wish to analyze the life-cycle impacts of materials that do not
require the use of a flame retardant, in order to select materials that pose the fewest life-cycle
impacts.
7.1 Preferable Human Health and Environmental Attributes
This section identifies a set of positive attributes for consideration when formulating or selecting
a flame retardant that will meet flammability standards. In general, a safer chemical has lower
human health hazard, lower ecotoxicity, better degradability, lower potential for bioaccumulation
and lower exposure potential. As described in Chapter 4, the toxicity information available for
each of the alternatives varies. Some hazard characterizations are based on measured data,
ranging from one study to many detailed studies examining multiple endpoints, doses and routes
of exposures. For other chemicals, there is no chemical-specific toxicity information available,
and in these cases either structure activity relationship (SAR) or professional judgment must be
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used. In Table 4-4 and Table 4-5, the hazard designations based on SAR or professional
judgment are listed in black italics, while those with hazard designations based on measured test
data are listed in color. Readers are encouraged to review the detailed hazard assessments
available for each chemical in Chapter 4.
Residual starting materials should be considered and ideally disclosed by the manufacturer in a
hazard assessment. If residual monomers were identified as more than 0.1 percent of the product
they were considered in the hazard assessment. It is possible DfE was not aware of/did not
predict residuals for some products. The user/purchaser of the flame retardants can ask the
manufacturer for detailed product certification to answer questions about residuals, oligomer
content or synthesis by-products.
7.1.1 Low Human Health Hazard
The DfE Program Alternatives Assessment Criteria for Hazard Evaluation addresses a consistent
and comprehensive list of human health hazard endpoints. Chemical hazards to human health
assessed in this report are: acute toxicity, carcinogenicity, genotoxicity, reproductive and
developmental toxicity, neurotoxicity, repeated dose toxicity, skin sensitization, respiratory
sensitization, eye irritation and dermal irritation. The DfE criteria describe thresholds to define
Low, Moderate, and High hazard. As described in Chapter 4, where data for certain endpoints
were not available or were inadequate, hazard values were assigned using data for structural
analogs, SAR modeling and professional judgment. In some cases (e.g., respiratory sensitization)
it was not possible to assign hazard values due to a lack of data, models, or structural analogs.
7.1.2 Low Ecotoxicity
Ecotoxicity includes adverse effects observed in wildlife. An aquatic organism's exposure to a
substance in the water column has historically been the focus of environmental toxicity
considerations by industry and government during industrial chemical review. Surrogate species
offish, aquatic invertebrates and algae are traditionally assessed to consider multiple levels of
the aquatic food chain. Aquatic organisms are a focus also because the majority of industrial
chemicals are released to water. Both acute and chronic aquatic toxicity should be considered in
choosing a chemical flame retardant. It is common to have limited data on industrial chemicals
for terrestrial wildlife. Some human health data (i.e., toxicity studies which use rodents) can be
relevant to non-human vertebrates in ecotoxicity evaluations. When evaluating potential
concerns for higher trophic level organisms (including humans), bioaccumulation potential
(discussed in Section 7.1.4) is an important consideration in conjunction with toxicity for
choosing a safer alternative.
7.1.3 Readily Degradable: Low Persistence
Persistence describes the tendency of a chemical to resist degradation and removal from
environmental media, such as air, water, soil and sediment. Chemical flame retardants must be
stable by design in order to maintain their flame retardant properties throughout the lifetime of
the product. Therefore, it is not surprising that all ten of the chemicals assessed in this report had
a persistence value of High or Very High.
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The half-life for a given removal process is used to assign a persistence designation. The half-life
measured or estimated to quantify persistence of organic chemicals is not a fixed quantity as is it
for a linear decay process such as for the half-life of a radioisotope. Chemicals with half-lives
that suggest low or no persistence can still present environmental problems. "Pseudo
persistence" can occur when the rate of input (i.e., the emission rate) of a substance exceeds the
rate of degradation in, or movement out of, a given area. With the current criteria, DfE did not
address pseudo persistence in the assessment which should include analysis of volumes of
production and release.
Environmental monitoring could bolster hazard assessments by confirming that environmental
fate is as predicted. The lack of such information should not be taken as evidence that
environmental releases are not occurring. Environmental detection is not equivalent to
environmental persistence; detection in remote areas (e.g., the Arctic) where a chemical is not
manufactured is considered to be a sign of persistence and transport from the original point of
release. An ideal safer chemical would be stable in the material to which it is added and have low
toxicity, but also be degradable at end of life of that material, i.e., persistent in use but not after
use. This quality is difficult to achieve for flame retardants.
In addition to the rate of degradation or measured half-life, it is important to be aware of the by-
products formed through the degradation process. In some cases, degradation products might be
more toxic, bioaccumulative or persistent than the parent compound. Some of these degradation
products are discussed in the hazard profiles, but a complete analysis of this issue is beyond the
scope of this assessment. The report did not consider toxicity from this potential degradation
route.
DfE cannot determine the likelihood of release of degradates. DfE includes this information in
the hazard profiles of relevant chemicals. Only degradants that were known or predicted to be
likely were included in the hazard assessments in this report. Stakeholders are encouraged to
conduct additional analyses of the degradation products of preferable alternatives using the
assessment methods described in Chapter 4.
In general, metal-containing chemicals are persistent. This is because the metal moiety remains
in the environment. Metal-containing compounds can be transformed in chemical reactions that
could change their oxidation state, physical/chemical properties, or toxicity. A metal-containing
compound may enter into the environment in a toxic (i.e., bioavailable) form, but degrade over
time into its inert form. The converse may also occur. The chemistry of the compounds and the
environmental conditions it encounters will determine its biotransformation over time. For
metals, information relevant to environmental behavior is provided in each chemical assessment
in Chapter 4 and should be considered when choosing an alternative.
7.1.4 Low Bioaccumulation Potential
The ability of a chemical to accumulate in living organisms is described by the bioconcentration,
bioaccumulation, biomagnification, and/or trophic magnification factors. Some of the
alternatives assessed in this report have a high level of potential for bioaccumulation, including
Fyrol PMP and the two reactive flame retardant resins. Based on SAR, the potential for a
molecule to be absorbed by an organism tends to be lower when the molecule is larger than
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1,000 daltons. The inorganic flame retardants assessed in this report have low potential to
bioaccumulate. Note that care should be taken not to consider the 1,000 daltons size to be an
absolute threshold for absorption - biological systems are dynamic and even relatively large
chemicals might be absorbed under certain conditions. Furthermore the initial 1,000 dalton
threshold was established based on the consideration of bioconcentration factors (BCFs).
Corresponding thresholds for hazard assessments based on bioaccumulation factor have not yet
been rigorously established.
The test guidelines available to predict potential for bioaccumulation have some limitations. For
example, they do not require the measurement for the BCFs of different components of a
mixture, even if they are known to be present in the test material and sufficiently precise
analytical methods are available. This situation often arises for lower molecular weight (MW)
oligomers or materials that have varying degree of substitution. Bioconcentration tests tend to be
limited for chemicals that have low water solubility (hydrophobic), and many flame retardants
have low water solubility. Even if performed properly, a bioconcentration test may not
adequately measure bioaccumulation potential if dietary exposure dominates over respiratory
exposure (i.e., uptake by fish via food versus via their gills). The Organisation for Economic
Cooperation and Development program recently updated the fish bioconcentration test, in which
dietary uptake is included for the first time (OECD, 2012). Dietary uptake is of critical
importance and may be a more significant route of exposure for hydrophobic chemicals.
7.1.5 Low Exposure Potential
For humans, chemical exposure may occur at different points throughout the chemical and
product life cycle; by dermal contact, by inhalation, and/or by ingestion; and is affected by
multiple physicochemical factors that are discussed in Chapter 5. The DfE alternatives
assessment assumes exposure scenarios to chemicals and their alternatives within a 'functional-
use' class to be roughly equivalent. The assessment also recognizes that in some instances
chemical properties, manufacturing processes, chemical behavior in particular applications, or
use patterns may affect exposure scenarios. For example, some flame retardant alternatives may
require different loadings to achieve the same flammability protection. Stakeholders should
evaluate carefully whether and to what extent manufacturing changes, life-cycle considerations,
and physicochemical properties will result in markedly different patterns of exposure as a result
of informed chemical substitution. For example, one chemical may leach out, or "bloom" out of
the polymer it is flame retarding faster than another, thus increasing its relative exposure during
use or disposal. The combination of high persistence and high potential for bioaccumulation
makes an alternative less desirable. Even if human toxicity and ecotoxicity hazards are measured
or estimated to be low, dynamic biological systems don't always behave as laboratory
experiments might predict. High persistence, high bioaccumulation chemicals, or their
degradation products, have high potential for exposure and unpredictable hazards following
chronic exposures that may not be captured in the hazard screening process.
Even if a chemical has negative human health and environmental attributes, concerns may be
mitigated if the chemical is permanently incorporated into a commercial product. In this case, the
potential for direct exposure to the chemical is greatly decreased or eliminated. Reactive flame
retardants are incorporated into the PCB laminate during the early stages of manufacturing. In
the case of TBBPA, it is reacted into the epoxy resin to form a brominated epoxy before the
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laminate production process begins. This brominated epoxy is the actual flame retardant that
provides the fire safety to the PCBs. Studies have shown that levels of free, unreacted TBBPA in
the brominated epoxy are extremely low. As referenced earlier in the report, one study by
Sellstrom and Jansson extracted and analyzed filings from a PCB containing a brominated epoxy
based on TBBPA. The study found that only 4 micrograms of TBBPA were unreacted for each
gram of TBBPA used to make the PCB (Sellstrom and Jansson, 1995).
7.2 Considerations for Poorly or Incompletely Characterized Chemicals
Experimental data for hazard characterization of industrial chemicals are limited. As described in
Chapter 4, for chemicals in this report without full data sets, analogs, SAR modeling, and
professional judgment were used to estimate values for those endpoints lacking empirical data.
No alternative chemical had empirical data for all of the hazard categories. Three of the 10
chemicals assessed lacked empirical data on at least 10 of the hazard endpoints. Several
chemicals included in this assessment appear to have more preferable profiles, with low human
health and ecotoxicity endpoints, although they are highly persistent, a frequent property for
flame retardants (see Table 4-4, and Table 4-5). There is less confidence in the results of some
seemingly preferable chemicals in which the majority of hazard profile designations are based on
estimated effect levels compared to chemicals with full experimental data sets. Empirical data
would allow for a more robust assessment that would confirm or refute professional judgments
and then support a more informed choice among alternatives for a specific use. Estimated values
in the report can, therefore, also be used to prioritize testing needs.
In the absence of measured data, DfE encourages users of this alternatives assessment to be
cautious in the interpretation of hazard profiles. Chemicals used at high volumes, or likely to be
in the future, should be given priority for further testing. Decision-makers are advised to read the
full hazard assessments for each chemical, available in Chapter 4, which may inform whether
additional assessment or testing is needed. Contact DfE with any questions on the criteria
included in hazard assessments or the thresholds, data, and prediction techniques used to arrive at
hazard values (www.epa.gov/dfe).
Where hazard characterizations are based on measured data, there are often cases where the
amount of test data supporting the hazard rating varies considerably between alternative
chemicals. In Table 4-4 and Table 4-5, the hazard characterizations based on SAR or
professional judgment are listed in black italics, while those with hazard characterizations based
on measured test data are listed in color. The amount of test data behind these hazard
characterizations shown in color can vary from only one study of one outcome or exposure, to
many studies in many species and different routes of exposure and exposure duration. In some
instances, testing may go well beyond basic guideline studies, and it can be difficult to compare
data for such chemicals against those with only a single guideline study, even though hazard
designations for both chemicals would be considered "based on empirical data" and thus come
with a higher level of confidence. Cases where one chemical has only one study but a second
chemical has many studies are complex and merit careful consideration. For hazard screening
assessments, such as the DfE approach, a single adequate study can be sufficient to make a
hazard rating. Therefore, some designations that are based on empirical data reflect assessment
based on one study while others reflect assessment based on multiple studies of different design.
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The hazard rating does not convey these differences - the full hazard profile should be consulted
to understand the range of the available data.
7.3 Social Considerations
Decision-makers should be mindful of social considerations when choosing alternative
chemicals. This section highlights occupational, consumer, and environmental justice
considerations. Stakeholders may identify additional social considerations for application to their
own decision-making processes.
Occupational considerations: Workers might be exposed to flame retardant chemicals from
direct contact with chemicals at relatively high concentrations while they are conducting specific
tasks related to manufacturing, processing, and application of chemicals (see Section 5.2). Many
facilities have established risk management practices which are required to be clearly
communicated to all employees. The National Institute for Occupational Safety and Health
(NIOSH) has established a hierarchy of exposure control practices16. From best to worst, the
practices are: elimination, substitution, engineering controls, administrative controls and personal
protection. Switching from high hazard chemicals to inherently lower hazard chemicals can
benefit workers by decreasing workplace risks through the best exposure control practices:
elimination and substitution of hazardous chemicals. While occupational exposures are different
to consumer exposures, workers are also consumers and as such workers are relevant to both
exposure groups.
Consumer considerations: Consumers are potentially exposed to flame retardant chemicals
through multiple pathways described in Chapter 5. Exposure research documents that people
carry body burdens of flame retardants. These findings have created pressure throughout the
value-chain for substitution, which impacts product manufacturers. DfE alternatives assessments
can assist companies in navigating these substitution pressures.
In recent years there has been a greater emphasis on 'green' products. In addition to substituting
in alternative chemicals, some organizations advocate for moving away from certain classes of
chemicals entirely (e.g., halogenated flame retardants), with product re-design, to avoid future
substitutions altogether. Product manufacturers should be mindful of the role of these
organizations in creating market pressure for alternative flame retardant chemicals and strategies,
and should choose replacement chemicals - or re-designs - that meet the demands of their
customers.
Environmental justice considerations: At EPA, environmental justice concerns refer to the
disproportionate impacts on people based on race, color, national origin, or income that exist
prior to or that may be created by the proposed action. These disproportionate impacts arise
because these population groups may experience higher exposures, are more susceptible in
response to exposure, or experience both conditions. Factors that are likely to influence
resilience/ability to withstand harm from a toxic insult can vary with sociodemographics (e.g.,
co-morbidities, diet, metabolic enzyme polymorphisms) and are therefore important
considerations. Adverse outcomes associated with exposure to chemicals may be
16 http ://www .cdc. gov/niosh/topics/engcontrols/
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disproportionately borne by people of a certain race, national origin or income bracket. Insights
into EPA's environmental justice policy can be accessed at:
www.epa.gov/compliance/ej/resources/policy/considering-ej-in-rulemaking-guide-07-2010.pdf.
Some populations have higher exposures to certain chemicals in comparison to the average
member of the general population. Low-income populations are over-represented in the
manufacturing sector, increasing their occupational exposure to chemicals. Higher exposures to
environmental chemicals may also be attributable to atypical product use patterns and exposure
pathways. This may be due to a myriad of factors such as cultural practices, language and
communication barriers, and economic conditions. The higher exposures may also be a result of
the proximity of these populations to sources that emit the environmental chemical (e.g.,
manufacturing industries, industries that use the chemical as production input, hazardous waste
sites, etc.), access to and use of consumer products that may result in additional exposures to the
chemical, or higher employment of these groups in occupations associated with exposure to the
chemical.
Considering environmental justice in the assessment of an alternative chemical may include
exploring product use patterns, pathways and other sources of exposure to the substitute,
recognizing how upstream factors such as socio-economic position, linguistic and
communication barriers, may alter typical exposure considerations. One tool available to these
populations is the Toxics Release Inventory (TRI), which was established under the Emergency
Planning and Community Right-to-Know Act to provide information about the presence,
releases, and waste management of toxic chemicals. Communities can use information reported
to TRI to learn about facilities in their area that release toxic chemicals and to enter into
constructive dialogue with those facilities. This information can empower impacted populations
by providing an understanding about chemical releases and the associated environmental impacts
in their community. Biomonitoring data for the alternative chemical, if available, can also signal
the potential for disproportionate exposure among populations with EJ issues.
7.4 Other Considerations
This section identifies performance and economic attributes that companies should consider
when formulating or selecting a flame retardant for use in PCBs. These attributes are critical to
the overall function and marketability of flame retardants and PCBs and should be considered
jointly with the human health and environmental attributes described above.
7.4.1 Flame Retardant Effectiveness and Reliability
The DfE approach allows companies to examine hazard profiles of potential replacement
chemicals so they can consider the human health and environmental attributes of a chemical in
addition to cost and performance considerations. This is intended to allow companies to develop
marketable products that meet performance requirements while reducing hazard. This section
identifies some of the performance attributes that companies should consider when formulating
or selecting a flame retardant, in addition to health and environmental consideration.
Performance attributes are critical to the overall function and marketability of flame retardants
and should be considered along with other factors.
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The ability of a product to meet required flammability standards is an essential performance
consideration for all flame retardant chemicals. The primary purpose of all flame retardants is to
prevent and control fire. According to the National Fire Protection Association, there
were 1,602,000 fires reported in the U.S. in 2005, causing 3,675 civilian deaths, 17,925 civilian
injuries, 87 firefighter deaths, and $10.7 billion in property damage (NFPA, 2007). Effective
flame retardants are needed to further reduce fire incidents and associated injuries, deaths, and
property damage. The fire safety requirements (e.g., a classification like UL (Underwriters
Laboratories) 94 VO) determine the necessary level of flame retardant that needs to be added to a
resin. Formulations are optimized for cost and performance, so that in some instances it may be
equally viable to use a small quantity of an expensive, highly efficient flame retardant or a larger
quantity of a less expensive, less efficient chemical.
In addition to flame retardancy properties, the flame-retarded product must meet all required
specifications and product standards (e.g., rigidity, compression strength, weight). The
polymer/fire retardant combination used in laminates which contain TBBPA may be complex
chemical formulations. In some instances, replacements exist which could allow for relatively
easy substitution of the flame retardant. However, a true "drop-in" exchange of flame retardants
is rare; some adjustment of the overall formulation, product re-design, or use of inherently flame
retardant materials is usually required. An alternative with similar physical and chemical
properties such that existing storage and transfer equipment as well as flame retardant
manufacturing technologies could be used without significant modifications. Unfortunately,
chemicals that are closer to being "drop-in" substitutes generally have similar physical and
chemical properties, and therefore are likely to have similar hazard and exposure profiles. Those
seeking alternatives to TBBPA should work with flame retardant manufacturers and/or chemical
engineers to develop the appropriate flame retardant formulation for their products.
Reliability is another aspect to consider in choosing a flame retardant. PCBs are used for many
purposes, including telecommunications, business, consumer, and space applications. The
environmental stresses associated with each application may be different, and so an ideal flame
retardant should be reliable in a variety of situations. Resistance to hydrolysis and photolysis, for
example, can influence the long-term reliability of a chemical flame retardant. For some
applications, it may be necessary for the flame retardant to be resistant against acidic, alkali, and
oxidative substances. These chemically demanding requirements have a direct effect on the
persistence of flame retardants (see Section 7.1).
7.4.2 Epoxy/Laminate Properties
Small changes in a flame-retardant formulation can significantly affect the manufacturability and
performance of PCB epoxies and laminates. In choosing a flame retardant for use in a PCB, it is
important to consider how the flame retardant will affect key properties of the PCB epoxy and
laminate, including glass transition temperature (Tg), mechanics (e.g., warpage, fracture
toughness, flexural modulus), electrics, ion migration, water uptake (moisture diffusivity), resin-
glass or resin-copper interface, color, and odor.
The glass Tg, for example, is particularly important for manufacturing lead-free PCBs. Due to
the higher soldering temperatures required for lead-free PCBs, epoxy and laminate glass Tgs
-------
must be high enough to prevent delamination of the PCB. Mechanical properties can also alter
the manufacturing process by impacting the ability to drill through the laminate.
Changes in a flame-retardant formulation can also affect overall epoxy and laminate
performance. Increased moisture diffusivity, for example, can reduce both the laminate and
overall PCB reliability. Changes to moisture diffusivity, as well as any other parameter that may
affect the electrical properties of the PCB should be considered. If the PCB cannot operate
properly, any benefits associated with less hazardous flame retardants are irrelevant. As
referenced in Section2.3, iNEMI (International Electronics Manufacturing Initiative) has
conducted a series of performance testing of commercially available halogen-free materials to
determine their electrical and mechanical properties.
7.4.3 Economic Viability
This section identifies economic attributes that companies often consider when formulating or
selecting a flame retardant. Economic factors are best addressed by decision-makers within the
context of their organization. Accurate cost estimations must be company-specific; the impact of
substituting chemicals on complex product formulations can only be analyzed in-house; and a
company must determine for itself how changes will impact market share or other business
factors. Cost considerations may be relevant at different points in the chemical and/or product
life cycle. These attributes are critical to the overall function and marketability of flame
retardants and flame-retardant products and should be considered jointly with performance
attributes, social considerations, and human health and environmental attributes.
Substituting chemicals can involve significant costs, as industries must adapt their production
processes, and have products re-tested for all required performance and product standards.
Decision-makers are advised to see informed chemical substitution decisions as long-term
investments, and to replace chemicals with those they anticipate using for many years to come.
This includes attention to potential future regulatory actions motivated by adverse human health
and environmental impacts, as well as market trends. One goal is to choose from among the least
hazardous options to avoid being faced with the requirement to substitute again.
To ensure economic viability, flame retardants must be easy to process and cost-effective in
high-volume manufacturing conditions. Ideally the alternative should be compatible with
existing process equipment at PCB manufacturing facilities. If it is not, the plants will be forced
to modify their processes and potentially to purchase new equipment. The ideal alternative would
be a drop-in replacement that has similar physical and chemical properties such that existing
storage and transfer equipment as well as PCB production equipment can be used without
significant modifications.
The four steps in the Flame Resistant 4 (FR-4) manufacturing process that typically differ
between halogenated and halogen-free materials are pressing, drilling, desmearing, and solder
masking (Bergendahl, 2004). As a result, manufacturing and processing facilities may need to
invest in new equipment in order to shift to alternatives flame retardants. In addition, daily
operation costs may be different for the new process steps required to manufacture PCBs with
alternative flame retardants.
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Flame-retardants that are either more expensive per pound or require more flame retardant per
unit area to meet the fire safety standards will increase the PCB's raw material costs. In this
situation, a PCB manufacturer will attempt to pass the cost on to its customers (e.g., computer
manufacturers), who will subsequently pass the cost on to consumers. However, the price
premium significantly diminishes over the different stages of the value chain. For an alternative
laminate, the price may be up to 20 to 50 percent higher per square meter, but for the final
product (e.g., a personal computer), the price premium can be less than 1 percent.
Handling, disposal, and treatment costs, as well as options for mechanical recycling, may be
important considerations when evaluating alternatives. Inherently high hazard chemicals may
require special engineering controls and worker protections that are not required of less
hazardous alternatives. Disposal costs for high hazard chemicals may also be much higher than
for low hazard alternatives. High hazard chemicals may be more likely to result in unanticipated
and costly clean-up requirements or enforcement actions should risk management protections fail
or unanticipated exposures or spills occur. Also, some chemicals may require specific treatment
technologies prior to discharge through wastewater treatment systems. These costs can be
balanced against potentially higher costs for the purchase of the alternative chemical. Finally,
initial chemical substitution expenses may reduce future costs of mitigating consumer concerns
and perceptions related to hazardous chemicals.
It should be noted that, while some assessed alternative chemicals included in this report are
currently manufactured in high volume, not all are currently available in quantities that would
allow their widespread use immediately. However, prices and availability may change if demand
increases.
7.4.4 Smelting Practices
Changes in flame-retardant formulation may also have implications for smelting processes.
Smelters have had to adapt their practices over time to respond to changing compositions and
types of electronic scrap as well as regulatory requirements (e.g., Waste Electrical and Electronic
Equipment directive). As discussed in Section 5.3.2, smelters process PCB materials through
complex, high-temperature reactions to recover precious and base metals (e.g., gold, silver,
platinum, palladium and selenium, copper, nickel, zinc, lead). Primary smelters in the world
(e.g., Boliden, Umicore, and Noranda) have learned how to operate with high loads of
halogenated electronic scrap and effectively control emissions of dioxins and furans, mercury,
antimony, and other toxic substances.
The consequences associated with the increased use of alternative flame retardants in FR-4 PCBs
from a smelting perspective are largely unknown. For example, the flame-retardant fillers silicon
dioxide and aluminum hydroxide are not expected to pose problems given that smelters routinely
process silicon dioxide and aluminum hydroxide because they are found in other feedstock.
Silicon dioxide is also beneficial in that it is used to flux the slag formed through the smelting
process. Aluminum oxide, derived from either metallic aluminum or from aluminum oxide or
hydroxide, can be tolerated in limited amounts. However, aluminum oxides are less effective
than brominated flame retardants, so a greater load of aluminum oxide is needed to achieve
similar flame retardancy. Whereas brominated flame retardants are typically found at 3 percent
of feedstock weight, aluminum hydroxide flame retardants can account for 15 percent of
7-10
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feedstock weight (Lehner, 2008). Since the slag used in base metals metallurgy have a limited
solubility for A12O3, completely replacing brominated flame retardants with aluminum oxide
flame retardants would challenge the smelters' recovery or energy balance. A substantial
increase in aluminum load would force smelters to use higher temperatures to overcome higher
liquid temperatures, or experience higher slag losses as a result of adding slag for dilution. The
added slag contains small, but measurable, contents of precious and base metals.
Phosphorus-based flame retardants are not expected to significantly change the composition of
the slag product or cause significant problems. However, formation of phosphine (PH3) from
phosphorus-based flame retardants, and acrolein, hydrogen cyanide, and PAH from nitrogen-
based flame retardants, is possible since most smelters operate under highly reducing conditions.
Furthermore, little to no information is available in the literature on the combustion byproducts
of phosphorus-based flame retardants under normal combustion conditions or elevated
temperatures approaching those found in incinerators or smelters. As is standard practice,
smelters will need to continuously evaluate if and how changes in flame-retardant formulation,
as well as the overall composition of PCBs, will affect their operating procedures and health and
safety practices.
7.5 Moving Towards a Substitution Decision
As stakeholders proceed with their substitution decisions for flame retardants in PCBs, the
functionality and technical performance of each product must be maintained, which may include
product performance in extreme environments over a life cycle of many years. Critical
requirements, such as product safety during operation cannot be compromised. When alternative
formulations are developed, the stakeholders should also consider the hazard profiles of the
chemicals used to meet product performance, with a goal to drive towards safer chemistry on a
path of continuous improvement.
When chemical substitution is the necessary approach, the information in this report can help
with selection of safer, functional alternatives. The hazard characterization, performance,
economic, and social considerations are all factors that will impact the substitution decision.
When choosing safer chemicals, alternatives should ideally have a lower human health hazard,
lower ecotoxicity, better degradability, lower potential for bioaccumulation, and lower exposure
potential. Where limited data are available characterizing the hazards of potential alternatives,
further testing may be necessary before a substitution decision can be made.
Switching to an alternative chemical is a complex decision that requires balancing all of the
above factors as they apply to a particular company's cost and performance requirements. This
report provides hazard information about alternatives to TBBPA to support the decision-making
process. Companies seeking a safer alternative should identify the alternatives that may be used
in their product, and then apply the information provided in this report to aid in their decision-
making process.
Alternative chemicals are often associated with trade-offs. For any chemical identified as a
potential alternative, some endpoints may appear preferable while other endpoints indicate
increased concern relative to the original chemical. A chemical may be designated as a lower
concern for human health but a higher concern for aquatic toxicity or persistence. For example,
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in the case of high MW polymers, where health hazards and potential bioaccumulation are
predicted to be low, one trade-off is high persistence. Additionally, there may be limited
information about the polymer's combustion by-products, or how the polymer behaves in the
environment and eventually degrades.
Trade-offs can be difficult to evaluate, and such decisions must be made by stakeholders taking
into account relevant information about the chemical's hazard, expected product use, and life-
cycle considerations. For example, chemicals expected to have high levels of developmental or
reproductive toxicity should be avoided for products intended for use by children or women of
child-bearing age. Chemicals with high aquatic toxicity concerns should be avoided if releases to
water cannot be mitigated. Nonetheless, even when certain endpoints are more relevant to some
uses than others, the full hazard profile must not be ignored.
7.6 Relevant Resources
In addition to the information in this report, a variety of resources provide information on
regulations and activities that include review or action on flame retardants at the state, national
and global levels, some of which are cited in this section.
7.6.1 Resources for State and Local Government Activities
University of Massachusetts at Lowell created a database which "houses more than 700 state and
local legislative and executive branch policies from all 50 states from 1990 to the present. The
online database makes it simple to search for policies that your state has enacted or introduced,
such as those that regulate or ban specific chemicals, provide comprehensive state policy reform,
establish biomonitoring programs, or foster "green" chemistry..." (National Caucus of
Environmental Legislators, 2008).
http://www.chemicalspolicv.org/chemicalspolicy.us.state.database.php
The Interstate Chemicals Clearinghouse (IC2) is an association of state, local, and tribal
governments that promotes a clean environment, healthy communities, and a vital economy
through the development and use of safer chemicals and products. The IC2 also created a wiki
page to allow stakeholders and members of state organizations to share resources for conducting
safer alternatives assessments.
http: //www. ne wmoa. org/preventi on/ic2/
http://www.ic2saferalternatives.org/
7.6.2 Resources for EPA Regulations and Activities
EPA's website has a number of resources regarding regulation development and existing
regulations, along with information to assist companies in staying compliant. Some of these sites
are listed below.
Laws and Regulations
http://www.epa.gov/lawsregs/
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Office of Pollution Prevention and Toxics (OPPT): Information on Polybrominated Diphenyl
Ethers
http://www.epa.gov/oppt/pbde/
EPA - OPPT's Existing Chemicals Program
http://www.epa.gov/oppt/exi stingchemical s/index. html
America's Children and the Environment
http://www.epa.gov/ace/
Integrated Risk Information System (IRIS)
http://www.epa.gov/IRIS/
Design for the Environment Program (DfE)
http://www.epa.gov/dfe
7.6.3 Resources for Global Regulations
The European Union (EU)'s REACH (Registration, Evaluation, Authorisation and Restriction of
Chemical substances) legislation was enacted in 2007 and has an "aim to improve the protection
of human health and the environment through the better and earlier identification of the intrinsic
properties of chemical substances" (European Commission, 201 la). Their website contains
information on legislation, publications and enforcement.
http://ec.europa.eu/environment/chemicals/reach/enforcement_en.htm
Under REACH, applicants for authorization are required to control the use of Substances of Very
High Concern (SVHC). If a SVHC does not have available alternatives, applicants must carry
out their own alternatives assessments. The European Chemicals Agency has published a
guidance document for this application that provides direction for conducting an alternatives
assessment, as well as creating a substitution plan.
http://echa.europa.eu/documents/10162/17229/authorisation application en.pdf
The EU also has issued the Restriction of Hazardous Substances directive which ensures that
new electrical and electronic equipment put on the market does not contain any of the six banned
substances: lead, mercury, cadmium, hexavalent chromium, poly-brominated biphenyls or
PBDEs above specified levels (European Commission, 201 Ib).
http://www.bis.gov.uk/nmo/enforcement/rohs-home
7.6.4 Resources from Industry Consortia
iNEMI is a consortium of electronics manufacturers, suppliers, associations, government
agencies, and academics. iNEMI has carried out a series of projects to determine the key
performance properties and the reliability of halogen-free flame-retardant PCB materials. Each
project has observed different outcomes, with the latest findings indicating that the halogen-free
flame-retardant laminates tested have properties that meet or exceed those of traditional
brominated laminates. Technology improvements, especially those that optimize the polymer/fire
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retardant combinations used in PCBs, have helped shift the baseline in regards to the
performance of halogen-free flame-retardant laminates.
At the time the 2008 draft report was released, iNEMI was conducting performance testing for
commercially available halogen-free flame-retardant materials to determine their key electrical
and mechanical properties under its HFR-free Program Report. The results of the testing and
evaluation of these laminate materials were made public in 2009.
The overall conclusions from the investigation were (1) that the electrical, mechanical, and
reliability attributes of the eleven halogen-free laminate materials tested were not equivalent to
FR-4 laminates and (2) that the attributes of the halogen-free laminates tested were not
equivalent among each other (Fu et al., 2009). Due to the differences in performance and
material properties among laminates, iNEMI suggested that decision-makers conduct testing of
materials in their intended applications prior to mass product production (Fu et al., 2009).
http://thor.inemi.org/webdownload/newsroom/Presentations/SMTA South China Aug09/HFR-
Free_Report_Aug09.pdf
iNEMI also conducted two follow-on projects to its HFR-free Program Report: (1) the HFR-Free
High-Reliability PCB Project and (2) the HFR-Free Leadership Program.
The focus of the HFR-Free High-Reliability PCB Project was to identify technology readiness,
supply capability, and reliability characteristics for halogen-free alternatives to traditional flame-
retardant PCB materials based on the requirements of the high-reliability market segment (e.g.,
servers, telecommunications, military) (iNEMI, 2014). In general, the eight halogen-free flame-
retardant laminates tested outperformed the traditional FR-4 laminate control (Tisdale, 2013).
http ://www.inemi. org/proj ect-page/hfr-free-high-reliability-pcb
The HFR-Free Leadership Program assessed the feasibility of a broad conversion to HFR-free
PCB materials by desktop and laptop computer manufacturers (Davignon, 2012). Key electrical
and thermo-mechanical properties were tested for six halogen-free flamed-retardant laminates
and three traditional FR-4 laminates. The results of the testing demonstrated that the computer
industry is ready for a transition to halogen-free flame-retardant laminates. It was concluded that
the halogen-free flame-retardant laminates tested have properties that meet or exceed those of
brominated laminates and that laminate suppliers can meet the demand for halogen-free flame-
retardant PCB materials (Davignon, 2012). A "Test Suite Methodology" was also developed
under this project that can inform flame retardant substitution by enabling manufacturers to
compare the electrical and thermo-mechanical properties of different laminates based on testing
(Davignon, 2012).
http ://www.inemi. org/proj ect-page/hfr-free-leadership-program
http ://thor.inemi. org/webdownload/Pres/APEX2012/Halogen-Free_Forum/HFR-
Free PCB Materials Paper 022912.pdf
HDPUG is a trade organization for companies involved in the supply chain of producing
products that utilize high-density electronic packages. HDPUG created a database of information
on the physical and mechanical properties of halogen-free flame-retardant materials, as well as
the environmental properties of those materials. The HDPUG project, completed in 2011,
broadly examined flame-retardant materials, both ones that are commercially viable and in
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research and development. For more information about the database and other HDPUG halogen-
free projects, visit: http://hdpug.org/content/completed-projects#HalogenFree.
7.7 References
Davignon, J. 2012. iNEMI HFR-Free PCB Materials Team Project: An Investigation to Identify
Technology Limitations Involved in Transitioning to HFR-Free PCB Materials.
http://thor.inemi.org/webdownload/Pres/APEX2012/Halogen-Free Forum/HFR-
Free PCB Materials Paper 022912.pdf (accessed July 30, 2014).
European Commission. (201 la). "REACH." Retrieved March 30, 2011, from
http://ec.europa.eu/environment/chemicals/reach/reach intro.htm.
European Commission. (201 Ib). "Working with EEE producers to ensure RoHS compliance
through the European Union." Retrieved March 30, 2011, from
http://www.rohs.eu/english/index.html.
Fu, H.; Tisdale, S.; Pfahl, R. C. 2009. iNEMI HFR-free Program Report.
http://thor.inemi.org/webdownload/newsroom/Presentati ons/SMTA_South_China_AugO
9/HFR-Free Report Aug09.pdf (accessed July 30, 2014).
iNEMI. HFR-Free High-Reliability PCB. http://www.inemi.org/project-page/hfr-free-high-
reliability-pcb (accessed July 30, 2014).
National Caucus of Environmental Legislators. (2008). "Lowell Center Releases Searchable
State Chemical Policy Database." Retrieved March 30, 2011, from
http://www.ncel.net/newsmanager/news_article.cgi?news_id=l 93.
OECD. (2012). "Section 3: Degradation and Accumulation." Retrieved April 9, 2012, from
http://www.oecd.Org/document/57/0.3746.en 2649 34377 2348921 1 1 1 l.OO.html.
Sellstrom, U.; Jansson, B. Analysis of tetrabromobisphenol a in a product and environmental
samples. Chemosphere, 1995, 31 (4), 3085-3092.
Tisdale, S. 2013. "BFR-Free High Reliability PCB Project Summary." Presented at the iNEMI
Sustainability Forum, APEX 2013. February 21, 2013. San Diego, CA.
http://thor.inemi.org/webdownload/Pres/APEX2013/Sustainabilitv Forum 022113.pdf
(accessed July 30, 2014).
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&EPA
United States
Environmental Protection
Agency
us. EM
FLAME RETARDANTS IN PRINTED CIRCUIT BOARDS
APPENDICES
August 2015
FINAL REPORT
A-l
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FLAME RETARDANTS IN PRINTED CIRCUIT
BOARDS: APPENDIX A
Yamada, Takahiro; Striebich, Richard. Open-
burning, Smelting, Incineration, Off-gassing of
Printed Circuit Board Materials Phase I Flow
Reactor Experimental Results Final Report.
Environmental Engineering Group, UDRI. August
11,2008
A-2
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Open-burning, Smelting, incineration, off-gassing of printed circuit
board materials, Phase I Flow Reactor Experimental Results
Final Report (August 11,2008)
Takahiro Yamada and Richard Striebich
Environmental Engineering Group
University of Dayton Research Institute
300 College Park KL102
Dayton, OH45469
A-3
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1. Introduction and Background
In this study we investigated the controlled exposure of various printed circuit boards (PCBs)
laminates to high temperature conditions. This work, combined with more realistic combustion
studies (Cone Calorimeter) will allow us to better understand the mechanisms of PCB thermal
destruction. This information will be used to evaluate existing and candidate flame retardants
used in the manufacturing of the PCBs. The combination of better controlled experiments with
actual combustion experiments will allow researchers and manufacturers to determine whether
candidate flame retardant material is better or worse than the existing formulations.
2. Experimental Setup
Figures 1 and 2 show an overview photo and a schematic of the experimental setup designed for
the project. A straight 28.5" long quartz reactor with 9.5x7mm o.d.xi.d. (QSI, Fairport Harbor,
OH) was used for pyrolysis experiments, and same reactor with 3 x 1mm i.d. xo.d. stem attached
to the straight main reactor at 5 Vi" from the reactor inlet end (QSI, Fairport Harbor, OH, custom
order) was used for the oxidation experiments. The narrow tubing was installed to introduce
oxygen for the combustion tests. Figure 3 shows detailed design of the modified reactor. New
reactor was used for each sample for pyrolysis experiments (100% N2). The same reactor was
used for the experiment with 10 and 21% O2 and N2 as bath gas. The samples were gasified
under pyrolytic condition for all experiments as seen in Figure 2. Blank experiments were
performed for each experiment, both pyrolysis and oxidation, to ensure that there was no carry
over from the previous experiments. The reactors were installed into 3-zone temperature
controlled furnace, 3/4" diameter and 24" length, SST-0.75-0-24-3C-D2155-AG S-LINE
(Thermocraft, Winston-Salem, NC.).
A-4
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Figure 1. Overview of experimental Setup
MSD
DB-5 Columr
GC
A(
1
aueo
3
us
3-Zone Furnace
1 ^
Reactor
If
/
>
^ miei
.Pyroprot
1 U 1
-O2 Inlet
Sampling
PtCoil
Quartz Tube
y y y y y y
Pyroprobe
Cirquit Board Sample
Figure 2. Schematic of experimental setup used for this project
3/4"
Figure 3. Detailed schematic of reactor inlet
Figure 4 shows the reactor temperature profiles at 300, 700, and 900°C. Based on the profiles,
effective length was determined to be 18" (from 6" to 24"). The effective length was used to set
gas flow rate to maintain 2 sec. of residence time for each temperature. The transfer line between
the reactor and GC oven was heated above 250°C.
A-5
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300C
700C
900C
Temperature (C)
800
600
400
200
0
- : :
: A
'
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Figure 4. Reactor temperature profiles for 300, 700, and 900°C
As shown in Figure 5, samples were gasified using a pyroprobe, CDS 120 Pyroprobe (CDS
analytical Inc., Oxford, PA). The sample (circuit board laminate) was cut into a small piece, 1.5
- 2 mm wide x 1cm long, and inserted into quartz cartridge, 3x4mm i.d.xo.d. 1" length (CDS
analytical Inc. Oxford, PA) as shown in Figure 6. The cartridge was then inserted into pyroprobe
for the gasification. When the sample was gasified, the pyroprobe temperature was increased
from room temperature to 900°C with a 20°C/ms ramp rate and held for 20 sec. at the final
temperature. The gasification process was repeated 3 times to ensure complete gasification. The
exhaust gas was passed through an impinger containing 20mL HPLC grade ultra-pure water
(Alfa Aesar, Ward Hill, MA) in a 40mL amber vial (WHEATON Industries Inc., Millville, NJ).
A small part of gas (ImL/min. flow rate) was introduced to Gas chromatograph / Mass
Spectrometer (HP 5890/5970 GC/MSD, Hewlett Packard, Pasadena, CA). The GC column used
for the analyte separation was DB-5MS, 30m length, 0.25mm i.d., 0.25um thickness (Agilent
J&W, Foster City, CA).
A-6
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Figure 5. Pyroprobe Pt filament
Figure 6. Pyroprobe cartridge with sample
A-7
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3. Experimental Conditions
Table 1 and 2 show the experimental conditions that were investigated in Phase I of the flow
reactor study. For the sample without copper laminate both pyrolysis and oxidation experiments
were performed. The samples with copper laminate were only subject to pyrolysis. Selected
experiments were repeated for pyrolysis at 700°C and 21% O2 at 900°C. The oxygen
concentrations of 10 and 21% were obtained by mixing nitrogen with 50% oxygen. The tables
describe experiments conducted on a "no Flame Retardant" sample (NFR), a conventional
"Brominated Flame Retardant" sample (BrFR), and candidate phosphorus sample (PFR).
Table 1
Experimental condition for the samples without Cu laminate (Unit: °C)
Sample
NFR
BrFR
PFR
N2
300, 700, 900
300, 700
300, 700
10% O2
700
700
700
21% O2
700, 900
300, 700, 900
300, 700, 900
Table 2 Experimental condition for the samples with Cu laminate (Smelting) (Unit: °C).
Sample
NFR w/Cu
BrFR w/Cu
PFR w/Cu
N2
900
900
900
Table 3 shows N2 and O2 (50%) flow rates for each temperature and oxygen concentration. The
flow rate was set to obtain 2 sec. residence time in the flow reactor, 18" length x 7mm i.d.
Table 3 N2, O2, and total flow rate used for each experimental condition (Unit: mL/min).
Temperature
300
700
900
O2 Cone. (%)
0
21
0
10
21
0
21
N2
274
159
162
130
94
134
78
O2 (50%)
0
115
0
32
68
0
56
Total
274
274
162
162
162
134
134
4. Results
4.1 TGA
Prior to the flow reactor incineration tests, thermogravimetric analysis (TGA) was conducted to
determine final gasification temperatures. TGA for all samples in N2 and air environments are
shown in Tables Al to A6 of Appendix A. Table 4 shows initial and final gasification
temperatures for each sample in N2 and air environments. The gasification initial and final
gasification temperatures vary for each sample. Those temperatures were lower when air was
used for the gasification in general. No weight loss was observed over 900°C for all samples;
therefore, pyroprobe final gasification temperature was set to 900°C.
-------
Table 4 Sample gasification starting and final temperatures, and its weight loss
Sample
Non-flame
Retardant w/Cu
Non-flame
Retardant
Non-flame
Retardant
Bromine Flame
Retardant w/Cu
Bromine Flame
Retardant
Bromine Flame
Retardant
Phosphorous Flame
Retardant w/Cu
Phosphorous Flame
Retardant
Phosphorous Flame
Retardant
Gasification
Environment
N2
N2
Air
N2
N2
Air
N2
N2
Air
Approx. Starting
Temperature (°C)
350
350
300
300
300
250
350
350
350
Approx. Final
Temperature (°C)
900
900
650
800
900
650
900
900
750
Weight Loss (%)
15.0
31.5
45.9
22.5
39.4
48.4
18.6
32.0
47.3
4.2 Major Combustion Byproduct Analysis
The major peaks of the total ion chromatograms (TIC) were identified for the each flame
retardant sample and experimental condition. Samples were introduced into the GC oven at a
flow rate of ImL/min., and cryogenically trapped at -30°C during combustion tests. After the
sample gasification and combustion, helium was introduced into the system for 3 minutes to
sweep the reactor system and pressurize GC column. The oven was, then, heated at 20°C/min
ramp rate up to 300°C and held 10 minutes. The results are shown in Figure Bl to B27 in
Appendix B. Some of the experiments were repeated to examine the consistency of the
experimental device. The repeatability experiments were conducted for the pyrolysis at 700°C,
and combustion with 21% O2 at 900°C for each of three samples. The results from these
experiments are shown in Figure 3B, 8B, 12B, 17B, 22B, and 27B in Appendix B. Most of the
compounds identified were aromatics. The most prevalent compounds from most pyrolysis and
oxidation experiments were benzene, toluene, xylene and its isomers, phenol, methylphenol and
its isomers, dimethyl phenol and its isomers, styrene, benzofuran and its derivatives,
dibenzofuran and its derivatives, xanthene, naphthofuran and its derivative, naphthalene,
biphenyl, biphenylene, fluorine, phenanthrene/anthracene. Major brominated compounds found
from the brominated flame retardant include bromo - and dibromo-phenols and hydrogen
bromide. Five largest peaks for each sample are listed in Table 5 for each temperature and
oxygen concentration. Phenol, methylphenol, toluene, xylene, and benzene were often observed
as major products. Dibromophenol was observed for brominated flame retardant at low
temperature, and Fffir was major brominated compound at the high temperature. Combined with
TIC shown in Appendix B, it is observed that in the pyrolytic environment (100%N2) brominated
flame retardant reduces number of byproducts at all temperatures, especially effective at low
A-9
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temperature (300°C). In the oxidative environment (10 and 21% 02) the brominated flame
retardant also reduces both number of combustion byproducts and their amount at all
temperatures. Phosphorous flame retardant reduces amount of combustion byproducts.
Increased oxygen level reduces number and amount of combustion byproducts. Increased
temperature also reduces number and amount of combustion byproducts, and byproducts are
decomposed to smaller compounds at the high temperature. Number of brominated compounds
were found at the trace level, and the identification of these compounds is described in Section
4.3. No phosphorous containing combustion byproducts were identified from the major peak of
phosphorous flame retardant combustion test. Phosphorus flame retardant combustion tests at
900C with 21% oxygen were repeated after the completion of a series of combustion tests which
produced skeptical results. When experiments were conducted under this condition initially,
only water was observed with very minor combustion byproduct peaks. When experiments were
repeated later, combustion byproducts were observed. TICs shown in Figure B26 and 27 are
results from the repeated experiments. The reason why only water was observed is still
unknown; however, problems with the mass selective detector (MSD) at that time could have
caused poor sensitivity. Byproducts observed in these most recent experiments were more
consistent with similar conditions and reactant feeds. Table 6 summarizes amount of sample
gasified and its weight loss.
Table 5. Major Combustion Byproducts under Different Experimental Conditions
Temp.
(°C)
300
700
Environment
Pyrolysis
Oxidation
(21%)
Pyrolysis
Major Combustion Byproducts (5 largest peaks in this order, top to
bottom) and Remarks
Non-FR
Phenol
Methylphenol
Toluene
Xylene
Xanthene
N.A.
Phenol
Methylphenol
Toluene
Xylene
Benzene
Br-FR
Phenol
Methyl ethylphenol
Methylphenol
Dibromophenol
Toluene
(only mono-ring
aromatics as a major
peaks)
Benzene
Methyl ethylphenol
Bromophenol
Dibromophenol
Tetramethylbenzene
Phenol
Toluene
Benzene
Methylphenol
Methylb enzofuran
(HBr observed)
P-FR
Phenol
Methylphenol
Dimethylpehnol
Toluene
Benzene
Phenol
Methylphenol
Dimethylphenol
Toluene
Xylene
Phenol
Methylphenol
Toluene
Benzene
Xylene
A-10
-------
Table 5. Major Combustion Byproducts under Different Experimental Conditions (Cont'd)
Temp.
(°C)
700
700
900
Environment
Oxidation
(10%)
Oxidation
(21%)
Pyrolysis
Oxidation
(21%)
Major Combustion Byproducts (5 largest peaks with this order, top to
bottom) and Remarks
Non-FR
Phenol
Benzene
Toluene
Methylphenol
Styrene
Benzene
Phenol
Benzofuran
Toluene
Styrene
Benzene
Toluene
Naphthalene
Biphenylene
Benzofuran
Benzene
Naphthalene
Benzofuran
Toluene
Biphenylene
(Benzene and
naphthalene are the
major products,
others are minor)
Br-FR
Benzene
Phenol
Toluene
Styrene
Naphthalene
(next biggest is
bromophenol, then
HBr)
Phenol
Benzene
HBr
Dibenzofuran
Naphthalene
Benzene
Toluene
Naphthalene
Styrene
Indene
Benzene
Naphthalene
HBr
Phenanthrene
Benzonitrile
P-FR
Phenol
Benzene
Toluene
Methylphenol
Styrene
Benzene
Phenol
Toluene
Styrene
Methylbenzofuran
Benzene
Naphthalene
Toluene
Biphenylene
Anthracene
Benzene
Naphthalene
Phenanthrene
Toluene
Biphenylene
Table 6. Amount of Samples Gasified and Their Gasification Rates
Sample
NFR
NFR w/Cu
O2 Cone.
(%)
0
10
21
0
Temp. (C)
300
700
900
700
700
900
900
Sample
Loaded (g)
0.013644
0.013336
0.014391
0.013610
0.012586
0.013780
0.013405
0.012944
0.022023
Amount
Gasified (g)
0.005086
0.005013
0.005431
0.005175
0.004722
0.005072
0.004966
0.004566
0.004382
Gasification
% by weight
37.3
37.6
37.7
38.0
37.5
36.8
37.0
35.3
19.9
Remarks
Duplicate
Duplicate
A-ll
-------
Table 6. Amount of Sample Gasified and its Gasification Rate (Cont'd)
Sample
BrFR
BrFR w/Cu
PFR
PFR w/Cu
O2 Cone.
(%)
0
10
21
0
0
10
21
0
Temp. (C)
300
700
700
300
700
900
900
300
700
700
300
700
900
900
Sample
Loaded (g)
0.012237
0.013009
0.012614
0.014123
0.010710
0.012087
0.012065
0.011910
0.021360
0.013881
0.014427
0.013556
0.013486
0.013447
0.013447
0.013853
0.013318
0.022780
Amount
Gasified (g)
0.004501
0.005157
0.004855
0.005989
0.003761
0.004404
0.004564
0.004450
0.004209
0.004689
0.005010
0.004717
0.004553
0.004108
0.004378
0.004564
0.004447
0.005374
Gasification
% by weight
36.8
39.6
38.5
42.4
35.1
36.4
37.8
37.3
19.7
33.8
34.7
34.8
33.8
30.5
32.6
32.9
33.4
23.6
Remarks
Duplicate
Duplicate
Duplicate
Duplicate
4.3 Detailed Brominated Flame Retardant Combustion Byproducts Analysis
Product yields
The major products generated at each temperature for each material are readily identified by GC-
MS analysis. However, because the samples after pyrolysis or oxidation are so complex,
additional analysis must be performed to examine the brominated byproducts constituents for
each sample. Since analysis of the products using standards is difficult due to the fact that there is
a thermal reactor in front of the GC-MS, the concentrations of the major compounds were
estimated. At 300°C in 0% oxygen atmosphere, the monobromophenol yield was estimated to be
1.2% of the mass of the board used. This estimate was calculated from the percentage of the
laminate gasified (37% from Table 5), and the area percentage of chromatographic response from
monobromophenol compared to the entire chromatographic run response (3.3%). The yield of the
other major product (dibromophenol) was estimated to be 0.67% of the weight of the board
exposed. These yields of the major products give an idea of the probable yield of the minor
products.
The major products reported for the brominated flame retardants were the mono and
dibrominated phenols. On the trace level (estimated as less than 1% of the total gaseous product
mixture), a wide variety of compounds were formed as shown in Table 7. Various brominated
aliphatic compounds were observed in small amounts, but the majority of compounds observed
were brominated aromatics. Generally aromatic compounds are more stable, so this observation
is appropriate.
A-12
-------
Fate ofbrominated combustion byproducts
It is clear that some of the compounds reported for trace brominated organics were probably
formed as products of incomplete combustion. This can be deduced because bromobenzene was
not observed at 300°C reactor temperature, but was observed in high amounts (on the trace level)
at higher temperatures. We suspect that the bromophenols are relatively stable at 300°C, but do
degrade at higher temperatures to form bromobenzenes and in one case, trace amounts of
bromobenzene diol. Even at reactor temperatures of 900°C in an air atmosphere, there was some
indication of the survival of these compounds through the reactor. At 900°C, the four brominated
compounds that could be observed were bromobenzene, bromobenzene diol, monobromophenol
and dibromophenol. Blank runs (no sample) were conducted between analyses for many of the
samples, and specifically between the 700°C oxidation experiment and the 900°C oxidation
experiment. None of the major or minor compounds were observed in these blank experiments.
Even trace concentrations ofbrominated compounds were a surprise at these conditions.
Oxidation at 900°C should have been sufficient to completely oxidize the entire sample. It could
be explained as follows: The sample was gasified instantaneously using pyroprobe. Because the
amount of gas generated was relatively large compared to the carrier gas, it might have created
oxygen deficit environment locally, and also there might not be enough time for gasified sample
to be mixed with oxygen. Less surprising was the survival of the bromobenzene and the
bromobenzene diol which were not present at temperatures of 300°C and were present at 700 and
900°C experiments. These clearly were formed as products during their time in the reactor, and
the degradation of these compounds was not completed by the time these compounds escaped the
high temperature reactor. From all this, we have learned that even at 2 seconds residence time in
an air atmosphere, there is a small amount of bromine which will not be converted to HBr. The
great majority of the brominated compounds, at these high temperatures, do convert to HBr.
However, on the trace level, there is good evidence that compounds are surviving the exposure.
This experimental system, because of its small sample size and short sampling time are not
appropriate to observe the formation ofbrominated dibenzodioxins and brominated
dibenzofurans. These types of compounds will be investigated in the larger scale systems.
A-13
-------
Table 7 Identified Brominated Byproducts
MW,
g/mol
120
122
136
172
250
206
262
246
156
234
214
292
290
compound
Br propene
Br propane
Br butane
Br phenol
Br2 phenol
Br naphthalene
Br dibenzodioxin
Brdibenzofuran
Br benzene
Br2 benzene
Br propyl phenol
Br2 propyl phenol
Br2 propenyl
phenol
Area counts (x10E-06) from the Total Ion Current for each compound
pyrolysis (N2 atmosphere)
300
2-1-2
4.9
1.0
25.5
101.0
55.0
ND
ND
ND
0.1
ND
3.5
ND
2.3
700
2-1-4
ND
ND
ND
84.0
27.7
ND
ND
ND
4.7
0.0
3.4
ND
ND
900
2-18-3
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
blank
2-18-2
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
oxidation (21% O2 atmosphere)
300
4-3-2
0.2
ND
6.6
130.0
93.0
ND
ND
ND
ND
ND
14.0
ND
2.1
700
4-3-4
0.1
ND
ND
147.0
69.6
ND
ND
ND
14.0
1.1
0.1
ND
ND
900
4-3-6
ND
ND
ND
31.1
7.5
ND
ND
ND
10.0
1.4
0.2
ND
ND
blank
4-3-5
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
4.4 Phosphorous Flame Retardant Combustion Byproducts Analysis
With regard to phosphorous-containing trace organic compounds, we were not able to observe,
even on the trace level, any phosphorus containing organic compounds. Several different
phosphorous compounds were selected which were aromatic phosphorus containing compounds,
including phenylphosphine, dimethyl phenylphosphine, phenylphosphinic acid, C3 phenyl
phosphine, phenylphosphonic acid, hydroxyphenylphosphonic acid, and C4 phenylphosphine.
The major ions from these compounds were checked for the phosphorous containing laminate
materials, and none of these compounds were observed, even on the trace level.
The literature suggests that radical capture is not the mechanism of flame retardancy in
phosphorous containing materials as it is with the brominated materials. Levchik and Weil1
report some good information about these flame retardant materials. In our sample, we suspect
that a aminophenyl phosphorous compound was used in the formulation as we do observe, on a
trace level, the compound aniline as one of the compounds formed at 300°C. Since many of the
phosphorous retardants work by forming phosphate on the surface of the material they are
protecting and "crusting" up the surface, we would expect aromatic formation from phenyl
groups in the flame retardant formulation and the phenol degradation to take place. We do
observe more polycyclic aromatic hydrocarbon (PAH) formation in this retardant than in the
brominated retardant. The mechanism by which phosphorous FRs retard flame (surface
complexes and PO2 interaction with H/OH) prohibits incorporation of phosphorus with stable
organic compounds. Thus, the phosphorous compounds could not be observed downstream of
the reactor.
A-14
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4.5 Hydrogen Chloride Analysis
During the course of experiments we were informed by the EPA that at least some (if not all) of
the samples contained chlorine. Standard epoxies used for the laminate contain 1000 to 2500
ppm (0.1 to 0.25 wt %) chlorine. Therefore, we also examined if exhaust gas contained hydrogen
chloride. Hydrogen chloride was found from brominated flame retardant pyrolysis and
combustion tests, and phosphorus flame retardant pyrolysis tests. No hydrogen chloride was
found from non-flame retardant pyrolysis and combustion tests. We did not look for chlorinated
organics, such as polychlorinated dibenzodioxin, in these samples as there was an extremely low
possibility of forming these organics at measurable levels with a flow reactor..
4.6 Aqueous Sample Analysis
The aqueous samples collected from combustion tests of BrFRs (w/o Cu) at 900°C with 21%
oxygen, and pyrolysis of BrFRs (w/o Cu) at 900°C, were analyzed for bromine ion concentration.
Results are shown in Table 8 and Figure Cl and C2 in Appendix C.
The samples were analyzed using a colorimetric method called Flow Injection Analysis (FIA)2'3.
In this analysis, bromine ions react with reagents to form a colored complex which absorbs at
590 nm. The absorbance measured at 590 nm is directly proportional to the bromine ion
concentration of the sample. Standards of 1, 2, 5, and 10 ppm are used for comparison to the
sample solutions (R2 = 0.9995). Figures Cl and C2 show the results of these two analyses. The
sample labeled Blank 30 did not generate a peak as would be expected. The sample labeled
BrFRCuP -1 (bromine flame retardant with Cu laminate) produced a negative peak, which was
observed in both runs. It is believed that some other ion in the sample matrix may have reacted
with method reagents to create a colored complex with a lower absorbance than the carrier
solution. A TIC taken at the same time (Figure B9) also showed no HBr and no other
brominated compounds. It is possible that Br reacted with copper in the pyroprobe to form
CuBr2, and it could have been condensed elsewhere on the reactor wall and transfer line. The
aqueous samples from the Br flame retardant without Cu laminate showed bromine ion in it.
Based on the XRF analysis, averaged Br concentration in the flame retardant sample was 6.17%.
The expected Br ion concentration from two brominated flame retardant combustion tests were
14.0 and 13.8 ppm if all bromine converted to HBr. 63 and 51% bromine was recovered as HBr
from the aqueous samples. The TIC taken at the same time (Figure B21 and B22) also
consistently showed a large HBr peak.
Table 8 Aqueous sample analysis for Br ion concentration
Sample
Br flame retardant w/o Cu 1st run (BrFR921-l)
Br flame retardant w/o Cu 2nd run (BrFR921-2)
Br flame retardant w/ Cu (BrFCuPl)
Br Ion Concentration (ppm)
Run 1
8.77
7.06
Not detected
Run 2
8.87
7.14
Not detected
After the flow reactor combustion test, Br transport efficiency test was conducted using
tetrabromobisphenol A (TBBPA) (Aldrich, St. Louis, MO) as a Br source. TBBPA was
A-15
-------
dissolved into methylene chloride and dried in the quartz cartridge that was used for sample
gasification. TBBPA was gasified in same manner as PCB samples. Reactor temperature was
set at 700°C, and gasified TBBPA was carried by N2 through reactor at the residence time of 2
sec. Sample was purged through a 40cc vial that contained 20cc HPLC grade ultrapure water.
Results were summarized in Table 9. Br recovery rate was 33.2%. At 700°C TBBPA will most
likely decompose to HBr, or dissociated Br atom may react with the quartz reactor tube. The
surface analysis and/or extraction of the reactor and transport line between reactor and vial could
be further performed to elucidate the Br recovery rate if funding situation allows us to do so.
Also our water impinger may not be sufficient to capture all HBr.
Table 9 Br transport test using TBBPA as a Br source
Sample
TBBPA
Br Introduced
as TBBA
(mg)
0.393
Expected Br if all Br
converted to HBr
(ppm)
11.5
Br recovered
from aqueous
sample (ppm)
3.82
Recovery
Rate as Br
(%)
33.2
5. Literature Review and Comparison
Relevant literature data for Br flame retardant circuit board and TBBPA pyrolysis and
combustion experiments was reviewed after the experiment to better understand our
experimental results. Grause et al.4 conducted the pyrolysis of TBBPA containing paper
laminated printed circuit board (PCB). The major constituents and their wt% of TBBA
containing PCB are C (57.0%), H (6.3%), and Br (3.64%). The sample was pyrolised in a quartz
glass reactor. The sample was heated from 50 to 800°C with a heating rate of lOK/min. and a N2
flow of lOOmL/min. The volatile products were gathered in four gas washbottles each containing
50mL of methanol. HBr content was determined by ion-chromatography (1C), and organic
products were analyzed by GC-MS. Methylated phenols and methylated benzene derivatives
were the most prominent degradation products after phenol. Also brominated phenols were
found among the degradation products of TBBA, with main products being 2-bromophenol, 2,4-
and 2,6-dibromophenols, and 2,4,6-tribromophenol. Most of the bromine was released in the
form of HBr (87%), another 14% was bound in organic compounds, and about 1.8% of original
bromine content was left in the residue. The release of the brominated aromatics was completed
below 400°C. However, only 50% of the bromine was released as HBr at this temperature.
Another 37% of HBr was released from the resin between 400 and 700°C. Barontini et al.5'6
investigated thermal decomposition products and decomposition pathways of electronic boards
containing brominated flame retardants using thermogravimetric (TG) FTIR and laboratory-scale
fixed bed tubular batch reactor coupled with GC-MS/FID. The major constituents and their wt%
are C (22.1-27.4%), H (2.0-2.4%), and Br (6.0- 6.9%). The degradation products identified
includes non-brominated aromatics (phenol, biphenyl, anthracene/phenanthrene, dibenzofuran,
dibenzo-p-dioxin, bisphenol A), brominated benzene, phenols, and dibenzofurans and dioxins.
Chien et al. 7 studied behavior of Br in pyrolysis of the printed circuit board waste. Pyrolysis of
the printed circuit board wastes was carried out in a fixed bed reactor at 623-1073K for 30 min.
in N2. Condensable product gases were analyzed using FTIR, and non-condensable gases were
scrubbed with NaOH solution. The main constituents and their wt% are C (52.2%), H (6.11%),
A-16
-------
Br (8.53%), and copper (9.53%). Approximately 72.3% of total Br in the printed circuit board
waste was found in product gas mainly as HBr and bromobenzene. Cu-O and Cu-(O)-Cu species
were observed in the solid residues. No Cu-Br species was found in the solid residue. Barontini
et al.8'9 also conducted TBBPA decomposition product analysis. The analytical technique
applied was similar to the one they conducted for Br flame retardant containing electronic
boards. Major products formed were HBr, phenol, mono, di, and tribromophenols, bisphenol A,
and brominated bisphenol A.
Our results show small amount of HBr for brominated flame retardant pyrolysis at 700°C, and
oxidation with 21% O2 at 300°C, and large amount of HBr for the oxidation with 10 and 21% O2
at 700°C and 21% O2 at 900°C. Our HBr recovery rate could have been greater, if multiple series
of impingers and more water were used. Also if samples were captured using methanol
impingers and analyzed using GC-MS as Grause et al. performed, instead of cryogenical trap,
more brominated organic could have been identified, even though we had also identified many
brominated organic compounds at the trace level. Experimental setup and analytical procedure
will be reconsidered and redesigned for Phase n experiment for the better sample identification
and bromine mass balance.
6. Conclusions
In this work, the controlled thermal exposure of flame-retardant and non-flame retardant
laminates was examined. Results for brominated flame retardant laminates showed that
bromophenol and dibromophenol were the main brominated organic products, with estimated
yields of 1.2% for methylbromophenol and 0.67% for the dibromophenol. The responses for
methylbromophenol and Dibromophenol decreased with increasing temperature, and were below
detectable levels for oxygen free experiments. However, oxidation experiments indicated that
even at 900°C, some amounts of organic bromine containing compounds survived. In addition,
bromobenzene and substituted bromophenols were formed at high temperatures, even though
they were not formed at the 300°C exposure (in both oxidation and pyrolysis). It is possible that
these bromophenols and bromobenzenes will be sources for the formation of products in the cone
calorimeter experiments, such as dioxins and furans.
Organic phosphorus compounds were not observed in the reactor exhaust gases during
phosphorus FR experiments. When phosphorus containing flame retardants are used, the product
distribution is similar to the non-flame retardant laminate experiments, in that there is a wide
variety of polycyclic aromatic hydrocarbons (PAHs) such as benzene, toluene, xylene, and
naphthalene. The results from this study suggests that cone calorimeter experiments will
generate a large amount of PAH type compounds for all of the laminate systems but that the
brominated system is likely to yield brominated dioxins and furans because of the relatively high
yields of brominated phenols observed at high temperatures in this study. In addition, the
compounds we should expect in the cone calorimeter are higher yields of methylbromophenol,
dibromophenol, bromobenzene (mono and di) as well as brominated and nonbrominated
fragments of bisphenol A, such as €3 substituted bromophenol, bromomethylphenol and the like.
All of the laminates formed large amounts of phenol and alkyl substituted phenols.
A-17
-------
These experiments did not use enough mass of laminate to perform dioxin and furan analysis on-
line. The investigation of these compounds should be performed with larger masses of sample
and using off-line analysis as it is being performed for the cone calorimeter experiments. The lab
scale experiments indicate that even under well controlled conditions, it is difficult to completely
degrade the brominated phenols, even at 900°C. While most of the bromine is converted to HBr,
its conversion is not complete unless very well controlled mixing is available to expose all of the
gaseous products to 21% oxygen.
References:
1. Levchik, S. V.; Weil, E. D. Fire Sci. 2006, 24, 345-364.
2. Anagnostopoulu, P. I; Doupparis, M. A. Anal. Chem. 1986, 58, 322-326.
3. Clesceri, L. S.; Greenberg, A. E.; Trussell, R. R.; American Public Health Association,
1989, p 4-11.
4. Grause, G.; Furusawa, M.; Okuwaki, A.; Yoshioka, T. Chemosphere 2008, 71, 872-878.
5. Barontini, F.; Cozzani, V. J. Anal. Appl. Pyrolysis 2006, 77, 41-55.
6. Barontini, F.; Marsanich, K.; Petarca, L.; Cozzani, V. Ind. Eng. Chem. Res. 2005, 44,
4186-4199.
7. Chien, Y.-C.; Wang, Y. P.; Lin, K.-S.; Huang, Y.-J.; Yang, Y. W. Chemosphere 2000,
40, 383-387.
8. Barontini, F.; Cozzani, V.; Marsanich, K.; Raffa, V.; Petarca, L. J. Anal. Appl. Pyrolysis
2004,72,41-53.
9. Barontini, F.; Marsanich, K.; Petarca, L.; Cozzani, V. Ind. Eng. Chem. Res. 2004, 43,
1952-1961.
A-18
-------
Appendix A
Thremogravimetric Analysis (TGA)
100
95
90
85
80
75
70
65
ISOOO Cu in nitrogen
ISOOO in nitrogen
200 400 600 800 1000
TemperaturejC
Figure Al. TGA in NI for Non-flame Retardant Sample with and without Cu Laminate
A-19
-------
100
90
80
70
60
50
ISOOO in air
100 200 300 400 500 600 700 800 900
TemperaturejC
Figure A2. TGA in Air for Non-flame Retardant Sample without Cu Laminate
A-20
-------
IS405 Cu in nitrogen
IS405 in nitrogen
100
95
90
85
80
75
70
65
60
200 400 600 800
1000
TemperaturejC
Figure A3. TGA in NI for Brominated Flame Retardant Sample with and without Cu
Laminate
A-21
-------
IS405 in air
100
90
80
70
60
50
100 200 300 400 500 600 700 800 900
TemperaturejC
Figure A4. TGA in Air for Brominated Flame Retardant Sample without Cu Laminate
A-22
-------
100
95
90
85
80
75
70
65
IS499 Cu in nitrogen
IS499 in nitrogen
200
400
600
800
1000
Figure A5. TGA in
TemperaturejC
for Phosphorous Flame Retardant Sample with and without Cu
Laminate
A-23
-------
IS499 in air
100
90
80
70
60
50
100 200 300 400 500 600 700 800 900
Temperature°C
Figure A6. TGA in Air for Phosphorous Flame Retardant Sample without Cu Laminate
A-24
-------
Appendix B
Total Ion Chromatogram Obtained from Circuit Board Combustion Byproducts Analysis
Table Bl Chemical Name - Structure Reference Table
Chemical Name
Benzene
Toluene
Xylene
(one of isomers)
Phenol
Methylphenol
(one of isomers)
Dimethylphenol
(one of isomers)
2-methylbenzofuran
Xanthene
1,2-dimethyl-
naphthofuran
Styrene
Chemical Structure
\ /
-OH
OH
'CH3
C,H,
A-25
-------
Table Bl Chemical Name - Structure Reference Table (Cont'd)
Dibenzofuran
Indene
Naphthalene
Biphenyl
Biphenylene
Fluorene
Phenanthrene
Tetramethylbenzene
(one of isomers)
Dibromophenol
(one of isomers)
Dimethylbenzofuran
(one of isomers)
CH3
H3C
•CH3
CH3
A-26
-------
Table Bl Chemical Name - Structure Reference Table (Cont'd)
Anthracene
Acetic Acid
Bromophenol
(one of isomers)
Methyl ethylphenol
(one of isomers)
Hydroxybiphenyl
(one of isomers)
Ethenylnaphthalene
(one of isomers)
Acenaphthylene
Methyl ethylphenol
(one of isomers)
Benzonitrile
H3C
OH
OH
Br
/ \
-CH(CH3)2
C2H3
H3C'
A-27
-------
Xylene Isomers
CH3
OH
Methylphenol
Isomers
OH
OH
2.OO 4.OO 6.OO 8.OO 1O.OO 12.OO 14.OO 16.OO 18.OO 2O.OO
Figure Bl. Total Ion Chromatogram (TIC) of Non-flame Retardant Sample
under Pyrolysis Condition at 300°C
A-28
-------
Xylene
Isomers
CH3
C2H3
Methylphenol
OH Isomers
OH
OH
2.OO 4.OO 6.OO 8.OO 1O.OO 12.OO 14.OO 16.OO 18.OO 2O.OO
Figure B2. Total Ion Chromatogram (TIC) of Non-flame Retardant Sample
under Pyrolysis Condition at 700°C
TIC: 2-15-2.D
TIC: 2-15-3.D
2.00 4.00 6.00
OO 10.00 12.00 14.00 16.00 18.00 20.00
Figure B3. Overlaid TIC for Repeated Experiment (Non-flame Retardant Sample
under Pyrolysis Condition at 700°C)
A-29
-------
b u n d a n c e
1.66+07 -
2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00
Figure B4. Total Ion Chromatogram (TIC) of Non-flame Retardant Sample under
Pyrolysis Condition at 900°C
A-30
-------
T IC: 2-1 8-1 .
8OOOOOO-
©OOOOOO
4OOOOOO
2OOOOOO
2.OO 4.OO S.OO 8.OO 1O.OO 12.OO
. OO 1S.OO 18. OO 2O.OO
Figure B5. Total Ion Chromatogram (TIC) of Non-flame Retardant Sample with Cu
Laminate under Pyrolysis Condition at 900°C. Peak identifications are same as above
(Figure B4).
A-31
-------
Abundant
OH
Methylphenol
Isomers
OH
OH
C2H5
2.00 4.00 6.00 8.00 1O.OO 12.OO 14.OO 1S.OO 18.OO 2O.OO
Time—>•
Figure B6. Total Ion Chromatogram (TIC) of Brominated Flame Retardant Sample
under Pyrolysis Condition at 300°C
A-32
-------
Methylphenol
Isomers
OH
2.OO 4.OO S.OO 8.OO 1O.OO 12. OO 14.OO 16.OO 18.OO 2O.OO
Figure B7. Total Ion Chromatogram (TIC) of Brominated Flame Retardant Sample
under Pyrolysis Condition at 700°C
T I C : 2 - 1 - 4 . D
T I C : 2 - 1 - 6 . D
1 .8 e + 0 7 -
1 .6 e + 0 7 -
1 .4 e + 0 7 -
1 .2 e + 0 7 -
1 e + 0 7 -
0 0 0 0 0 0 -
6000000 -
4000000 -
2000000 -
2.00 4.00 6.00
00 20.00
Figure B8. Overlaid TIC for Repeated Experiment (Brominated Flame Retardant Sample
under Pyrolysis Condition at 700°C)
A-33
-------
C2H3
.A, buricia nc.es
2. OO 4. OO e. OO Q. OO 10. OO 12. OO 14. OO 1 e. OO 1Q. OO 2O. OO
Figure B9. Total Ion Chromatogram (TIC) of Brominated Flame Retardant Sample
with Cu Laminate under Pyrolysis Condition at 900°C
A-34
-------
1 .ee-i-07
1e-i-07
eOOOOOO
6OOOOOO-
4000000
2OOOOOO
Methylphen
ol Isomers
OH
OH
Xylene Isomer:
CH
2.OO 4.OO 6.OO B.OO 1O.OO 12.OO 14.OO 16.OO 1B.OO 2O.OO
ST1C5 >=
Figure BIO. Total Ion Chromatogram (TIC) of Phosphorous Flame Retardant Sample
under Pyrolysis Condition at 300°C
A-35
-------
Xylene
Isomers
CH3
Methylphen
ol Isomers
CH,
2.OO 4.OO S.OO 8.OO 1O.OO 12.OO 14.OO 1S.OO 18.OO 2O.OO
Figure Bll. Total Ion Chromatogram (TIC) of Phosphorous Flame Retardant Sample
under Pyrolysis Condition at 700°C
1 .8 e + Q 7 -
1 .6 e + 0 7 -
1 .4 e + 0 7 -
1 .2 e + 0 7 -
1 e + 0 7 -
0 0 0 0 0 0 -
6000000 -
4000000 -
2000000 -
TIC : 2 - 8 -4 . D
TIC : 2 - 8 -6 . D
2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00
Figure B12. Overlaid TIC for Repeated Experiment (Phosphorous Flame Retardant
Sample under Pyrolysis Condition at 700°C)
A-36
-------
C2H3
Abundance
2.OO 4.OO 6.OO 8.OO 1O.OO 12.OO 14.OO 16.OO 18.OO 2O.OO
Figure B13. Total Ion Chromatogram (TIC) of Phosphorous Flame Retardant Sample
with Cu Laminate under Pyrolysis Condition at 900°C
A-37
-------
Abundance
2.5e+07 -
2e+07 -
1.5e+07 -
1e+07 -
5000000 -
Xylene
Isomers
C2H3
CH3
OH
17-2Methylphen
ol Isomers
Time—>
2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 24.00 26.00
Figure B14. Total Ion Chromatogram (TIC) of Non-flame Retardant Sample
under 10% O2 Condition at 700°C
A-38
-------
Abundance
2.5e+07 -
2e+07 -
1.5e+07 -
1e+07 -
5000000 -
Xylene
Isomers
CH3
C2H3
Methylphen
ol Isomers
OH
2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 24.00 26.00
Time-->
Figure B15. Total Ion Chromatogram (TIC) of Non-flame Retardant Sample
under 21% O2 Condition at 700°C
A-39
-------
A b u n dance
3e+07 -
2 .5e +07 -
2e+07 -
1 .5e +07 -
1e+07 -
5000000 -
2.00 4.00 6.00 8.0010.0012.0014.0016.0018.0020.0022.0024.0026.00
Figure B16. Total Ion Chromatogram (TIC) of Non-flame Retardant Sample
under 21% O2 Condition at 900°C
A b u n d a n c e
3e+07 :
2.5e + 07 -
2e+07 -
1.5e + 07 :
1 e + 07 :
5000000 :
TIC : 3-1 8-4.D
TIC : 3-1 8-7.D
2.00 4.00 6.00 8.00 10.0012.0014.0016.0018.0020.0022.0024.0026.00
T i rn e - - >
Figure B17. Overlaid TIC for Repeated Experiment (Non-flame Retardant Sample under
21% O2 Condition at 900°C)
A-40
-------
A b u n dance
OH
OH
2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 24.00 26.00
T inn e~~>
Figure B18. Total Ion Chromatogram (TIC) of Brominated Flame Retardant Sample
under 21% O2 Condition at 300°C
A-41
-------
C2H3
A b u n d a n c e
CH;
TI ITI e -
2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 24.00 26.00
Figure B19. Total Ion Chromatogram (TIC) of Brominated Flame Retardant Sample
under 10% O2 Condition at 700°C
A-42
-------
TIC : 4 - 3 - 6 . D
6500000
6000000
5500000
5000000
4500000
4000000
3500000
3000000 -
2500000 -
2000000 -
1500000 -
1000000 -
500000 -
0
2.00 4.00 6.00
.00 10.0012.0014.0016.0018.0020.0022.0024.0026.00
Figure B20. Total Ion Chromatogram (TIC) of Brominated Flame Retardant Sample
under 21% O2 Condition at 700°C
A-43
-------
Abundance
2.00 4.00 6.00 8.00 10.0012.0014.0016.0018.0020.0022.0024.0026.00
Tim e—>
Figure B21. Total Ion Chromatogram (TIC) of Brominated Flame Retardant Sample
under 21% O2 Condition at 900°C
Abundance
7000000 -
6000000 :
5000000 -
4000000 :
3000000 -
2000000 :
1000000 :
0
TIC: 4-3-8.D
TIC: 4-3-10.D
2.00 4.00 6.00 8.00 10.0012.0014.0016.0018.0020.0022.0024.0026.00
Tim e~>
Figure B22. Overlaid TIC for Repeated Experiment (Brominated Flame Retardant Sample
under 21% O2 Condition at 900°C)
A-44
-------
2 . 4 e + 0 7 ^
2 . 2 e + 0 7 -
2 e + Q 7 -
1.88 + 07 -
1 . 6 e + 0 7 -
1 . 4 e + Q 7 ^
1 . 2 e + 0 7 -
1 e + Q 7 -
8QQQQQQ ^
6QQQQQQ -
4QQQQQQ -
2QQQQQQ -_
0 -
Xylene
Isomers
CH3
Methylphenol
Isomers
OH
Dimethylphenol
Isomers
2.00 4.00 6.00 8.00 10.0012.0014.0016.0018.0020.0022.0024.0026.00
Figure B23. Total Ion Chromatogram (TIC) of Phosphorous Flame Retardant Sample
under 21% O2 Condition at 300°C
A-45
-------
Abundance
2.5e+07 -
2e+07 -
1.5e+07 -
1e+07 -
5000000 -
Xylene
Isomers
CH3
C2H3
Methylphen
ol Isomers
OH
2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 24.00 26.00
Time—>
Figure B24. Total Ion Chromatogram (TIC) of Phosphorous Flame Retardant Sample
under 10% O2 Condition at 700°C
A-46
-------
C2H3
2 .2 e + 0 7
2 e + 0 7
1 .8 e + 0 7
1 .6 e + 0 7
1 . 4 e + 0 7
1 .2 e + 0 7
1 e + 0 7
8 0 0 0 0 0 0
6 0 0 0 0 0 0
4 0 0 0 0 0 0
2 0 0 0 0 0 0
0
CH3
'CH3
2 .0 0 4 .0 0 6 .0 0 8 .0 0 1 0 .0 01 2 . 0 01 4 . 0 01 6 .0 01 8 .0 02 0 . 0 02 2 .0 02 4 .0 02 6 .0 0
Figure B25. Total Ion Chromatogram (TIC) of Phosphorous Flame Retardant Sample
under 21% O2 Condition at 700°C
A-47
-------
A b u ft d a n c e
8000000 -
7000000 -
6000000 -
5000000 -
4000000 -
3000000 -
2000000 :
1000000 -
0 -
2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 24.00 26.00
TI e ~~>
Figure B26. Total Ion Chromatogram (TIC) of Phosphorous Flame Retardant Sample
under 21% O2 Condition at 900°C
A b u n d a n c e
1.16+07
1 e + 0 7
9000000
8000000
7000000
6000000
5000000
4000000
3000000
2000000
1000000
0
TIC : 8 -5 - 2 . D
TIC : 8 -6 -2 .D
2.00 4.00 6.00 8.00 10.0012.0014.0016.0018.0020.0022.0024.0026.00
Figure B27. Overlaid TIC for Repeated Experiment (Phosphorous Flame Retardant
Sample under 21% O2 Condition at 900°C)
A-48
-------
Appendix C
Aqueous Sample Ion Chromatogram Analysis
Insliumenl 1 BROMIDE MET SYSTESTTRA080410AFDT [Channel 2 - Analyle 2]
HHQ
is
Figure Cl. FIA Analysis of Aqueous Samples Run 1
Blank 30: Blank Sample
BrMB 1: Aqueous sample for TBBA standard used for Br mass balance test.
BrMB2: Bromide standard for cross check
BrFR921-l: Aqueous sample for Br flame retardant combustion test at 900°C with 21%
O2.
BrFR921-2: Aqueous sample for Br flame retardant combustion test at 900°C with 21%
O2, repeated.
BrFRCuPl: Aqueous sample for Br flame retardant with Cu laminate combustion test
at 900°C in pyrolysis.
A-49
-------
nstalment 1-BROMIDE.MET-SYSTEST.TRA-080410B.FDT - [Channel 2 - Analyte 2]
• File Method Iiay DflM Data Window Help
HHE
clliod | T.ay | DQM | DM \ |Analyl« | Ttay | | Tra
Tim*: 972.26 Seconds Amp: 0 Volt;
rHelp, press F1
Blank 30:
BrMBl:
BrMB2:
BrFR921-l:
BrFR921-2:
BrFRCuPl:
A
Figure C2. FIA Analysis of Aqueous Samples Run 2
Blank Sample
Aqueous sample for TBBA standard used for Br mass balance test.
Bromide standard for cross check
Aqueous sample for Br flame retardant combustion test at 900°C with 21%
O2.
Aqueous sample for Br flame retardant combustion test at 900°C with 21%
O2, repeated.
Aqueous sample for Br flame retardant with Cu laminate combustion test
at 900°C in pyrolysis.
A-50
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FLAME RETARDANTS IN PRINTED CIRCUIT
BOARDS: APPENDIX B
Sidhu, Sukh; Morgan, Alexander; Kahandawala,
Moshan; Chauvin, Anne; Gullett, Brian; Tabor,
Dennis. Use of Cone Calorimeter to Estimate
PCDD/Fs and PBDD/Fs Emissions From
Combustion of Circuit Board Laminates. U.S.
EPA and UDRI. March 23, 2009
A-51
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USE OF CONE CALORIMETER TO ESTIMATE PCDD/Fs AND PBDD/Fs EMISSIONS
FROM COMBUSTION OF CIRCUIT BOARD LAMINATES
Sukh Sidhu, Alexander Morgan, Moshan Kahandawala,
Anne Chauvin, Brian Gullett, Dennis Tabor
UDRI and EPA
March 23, 2009
The purpose of this study was to use a cone calorimeter to measure emissions from fully
ventilated combustion of printed circuit board laminates. The cone calorimeter (FTT Dual Cone
Calorimeter) was modified in order to allow for isokinetic sampling of the exhaust gas. USEPA
method 23 was used to sample and analyze Polychlorinated Dibenzo-p-Dioxins and Furans
(PCDD/Fs) and Polybrominated Dibenzo-p-Dioxins and Furans (PBDD/Fs) from combustion of
circuit board laminates. The cone calorimeter experiments were conducted at the University of
Dayton Research Institute (UDRI). The exhaust gas samples were extracted and analyzed at the
EPA Research Triangle Park laboratory. This report presents and discusses experimental and
analytical data from both institutions.
BrFR or BFR or BR FR = laminate containing brominated flame retardant
PFR = laminate containing phosphorous based flame retardant
NFR = laminate without a flame retardant
A-52
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MATERIAL AND METHODS
Cone Calorimeter
The cone calorimeter is a fire testing instrument that measures the inherent flammability of a
material through the use of oxygen consumption calorimetry [1]. It is based on the principle that
the net heat of combustion of any organic material is directly related to the amount of oxygen
required for combustion [2]. The cone calorimeter is a standard technique under ASTM E-
1354/ISO 5660 [3, 4] and is commonly used as a fire safety engineering tool. Under the ASTM
E-1354/ISO 5660 method, small samples (100 cm2 squares up to 50-mm thick) of combustible
materials are burned and a wide range of data can be obtained. Through oxygen consumption
calorimetry, heat release rate data can be obtained and sensors on the cone calorimeter can
measure smoke release, CO/CO2 production rates, mass loss rate and several other flammability
properties such as time to ignition and fire growth rate.
A schematic of the UDRI cone calorimeter apparatus is shown in Figure 1. At the core of the
equipment is a radiant cone heater, hence the name 'cone calorimeter'. A sample is placed at the
center of the cone heater on the sample holder with dimensions of 100 mm x 100 mm. The cone
heater provides a constant heat flux to the sample. Ignition of the sample is provided by a spark
igniter located above the sample. The exhaust gas contains smoke and products of combustion.
The constant ventilation is maintained by the blower. The cone calorimeter mimics a well-
ventilated forced combustion of an object being exposed to a constant heat source and constant
ventilation [5, 6].
A-53
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Several measurements can be obtained from the cone calorimeter. A load cell continuously
measures the mass loss of the sample as it burns. Gases from the fire are carried past a laser
photometer beam to measure smoke density and to a sampling ring which carries the gases to a
combined CO/CO2/O2 detector. Once the gases from the sampling ring have been analyzed, one
can obtain CO and CO2 production rates as a function of time which can give insight into the
heats of combustion for the material, as well as combustion efficiency. Oxygen consumption is
measured in the exhaust stream using an oxygen sensor (paramagnetic). The heat release rate is
determined from oxygen consumption calorimetry. Temperature and pressure measurements are
also taken at various locations in the exhaust duct.
loser photometer beam
vincludlng temperature measurement
Temperature and differential
pressure measurements taken here
Soot sample tube
€xhcust
blower
Soot collection filter
€xhaust
hood
Spark igniter
Load cell
Vertical orientation
Figure 1. Schematic of Cone Calorimeter used at UDRI
The Cone calorimeter data collected during a test can reveal scientific information about material
flammability performance. All measured data are defined below:
A-54
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• Time to ignition (Tig): Measured in seconds, this is the time to sustained ignition of the
sample. Interpretation of this measurement assumes that shorter times to ignition mean that
samples are easier to ignite under a particular heat flux.
r\
• Heat Release Rate (HRR): The rate of heat release, in units of kW/m , as measured by
oxygen consumption calorimetry.
• Peak Heat Release Rate (Peak HRR): The maximum value of the heat release rate during the
combustion of the sample. The higher the peak HRR, the more likely that flame will self-
propagate on the sample in the absence of an external flame or ignition source. Also, the
higher the peak HRR, the more likely that the burning object can cause nearby objects to
ignite.
• Time to Peak HRR: The time to maximum heat release rate. This value roughly correlates
the time it takes for a material to reach its peak heat output, which would in turn sustain
flame propagation or lead to additional flame spread. Delays in time to peak HRR are
inferred to mean that flame spread will be slower in that particular sample, and earlier time to
peak HRR is inferred to mean that the flame spread will be rapid across the sample surface
once it has ignited.
• Time to Peak HRR - Time to Ignition (Time to Peak HRR - Tig): This is the time in
seconds that it takes for the peak HRR to occur after ignition rather than at the start of the test
(the previous measurement). This can be meaningful in understanding how fast the sample
reaches its maximum energy release after ignition, which can suggest how fast the fire grows
if the sample itself catches fire.
A-55
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• Average Heat Release Rate (Avg HRR): The average value of heat release rate over the
entire heat release rate curve for the material during combustion of the sample.
• Starting Mass, Total Mass Lost, Weight % Lost. These measurements are taken from the
load cell of the cone calorimeter at the beginning and end of the experiment to see how much
total material from the sample was pyrolyzed/burned away during the experiment.
r\
• Total Heat Release (THR). This is measured in units of MJ/m and is basically the area
under the heat release rate curve, representing the total heat released from the sample during
burning. The higher the THR, the higher the energy content of the tested sample. THR can
be correlated roughly to the fuel load of a material in a fire, and is often affected by the
chemical structure of the material.
• Total Smoke Release: This is the total amount of smoke generated by the sample during
burning in the cone calorimeter. The higher the value, the more smoke generated either due
to incomplete combustion of the sample, or due to the chemical structure of the material.
• Maximum Average Heat Rate Emission (MAHRE): This is a fire safety engineering
parameter, and is the maximum value of the average heat rate emission, which is defined as
the cumulative heat release (THR) from t=0 to time t divided by time t [7]. The MAHRE can
best be thought of as an ignition modified rate of heat emission parameter, which can be
useful to rank materials in terms of ability to support flame spread to other objects.
• Fire Growth Rate (FIGRA): This is another fire safety engineering parameter, determined by
dividing the peak HRR by the time to peak HRR, giving units of kW/m2 per second. The
FIGRA represents the rate of fire growth for a material once exposed to heat, and higher
FIGRA suggest faster flame spread and possible ignition of nearby objects [1].
A-56
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Isokinetic Sampling
In this project, the cone calorimeter was utilized to combust the various circuit board
laminates and collect products released during their combustion. The USEPA method 23 was
used to isokinetically sample a portion of the exhaust gases flowing through the exhaust duct.
The cone calorimeter was modified to allow for the isokinetic sampling device to be inserted into
the exhaust duct.
The main characteristic of isokinetic sampling is that the extraction of the gas sample from
the main gas stream is at the same velocity as the gas travelling through the stack. This sampling
method is easily adaptable and is commonly used to test for many organic pollutants such as
polychlorinated biphenyls (PCBs), dioxins/furans and polycyclic aromatic hydrocarbons (PAHs)
[8]. The compounds of interest are retained in a glass fiber filter and Amberlite XAD-2 adsorbent
resin.
Apex Instruments Model MC-500 Series Source Sampler Console and Isokinetic System
were used for this experiment and contained five main components: the source sampler console,
the external vacuum pump unit, the probe assembly, the modular sample case and the umbilical
cables. A picture of the Apex instrument isokinetic source sampling equipment is shown in
Figure 2.
A-57
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Modular sample case
Source sampler console
External vacuum pump unit
. •
Umbilical cables
Figure 2. Isokinetic Sampling train used at UDRI
The modular sample case contained a heated box for the filter assembly and a cold box
for the impinger glassware and condenser. The sampling nozzle of the heated transfer line was
inserted into the exhaust duct, which was modified by adding holes into the side to allow for the
device to be inserted. Figure 3 shows the modifications made to the exhaust system of the cone
calorimeter. A picture of the cone calorimeter and the isokinetic sampling system assembly is
shown in Figure 4.
Cone Calorimeter
Figure 3. Modification of duct and sampling port of the UDRI cone calorimeter
A-58
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Figure 4. Cone calorimeter and isokinetic sampling system assembly
The heated probe connected the nozzle to the filter assembly where the soot was retained.
The mass of the filter before and after sampling was recorded to obtain the mass of soot formed
during the combustion of the samples (see data in the Appendix, Table 1). The filter assembly
was also connected to a condenser followed by an adsorbent trap and a series of four impingers.
The moisture formed in the condenser deposited as droplets in the first empty impinger and
therefore could not be quantified. The adsorbent trap contained about 40 g of hydrophobic resin
XAD-2, glass wool and 100 jiL of surrogate standard solution. The surrogate standard solution
contained 13Ci2 labeled standards of PCDD/Fs to evaluate the method. Due to lack of standards
for PBDD/Fs, no 13Ci2 labeled standards of PBDD/Fs were spiked into the samples prior to
sampling. XAD-2 was used to absorb the soluble organic compounds from the effluent gas. The
second impinger contained about 100 mL of water, the third one was empty and the fourth one
contained about 200 g of silica gel and was connected to a thermocouple. All three impingers
were used to collect any extra moisture in the effluent gas. The mass of silica gel was recorded
A-59
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before and after sampling to obtain the mass of moisture content in the effluent gas (see data in
Appendix, Table 1). The third impinger appeared to stay dry throughout the experiment (few
water droplets on the sides could not be quantified). The amount of water in the second impinger
was recorded before and after sampling (see data in Appendix, Table 1) and appeared to
decrease. This might be explained by the fact that some of the water could have been carried
away by the effluent gas and was collected in the fourth impinger with the silica gel.
After assembling the sampling train, the system had to be checked for leaks. Throughout the
runs, the temperature inside the probe and inside the filter was controlled and maintained at
120°C from the source sampler console. The cold box temperature was maintained under 20°C
by adding ice water to it. The pump flow rate was maintained at 0.1104 L/s and the exhaust flow
rate was maintained at 15 L/s throughout the experiment. The flow rate through the probe was
controlled and maintained steady by adjusting the flow rate through the stack and therefore a
pitot tube was not necessary.
After sampling, the filter and soot, as well as the soot in the probe, nozzle and front half of
the filter holder, XAD-2 resin and water from the second impinger were combined for a single
analysis. The filter was placed in container No. 1. Container No. 2 contained the soot deposited in
the nozzle, transfer probe and front half of filter holder as well as all the methylene chloride and
acetone rinses. Container No. 3 contained the same material as container No. 2 with toluene as
the rinse solvent. The water was also placed in a container for analysis and the silica gel was
discarded. After sampling, the duct and exhaust hood were dismantled and thoroughly cleaned
with hexane to avoid any risk of contamination from combustion of one type of circuit board to
the next. The sampling method and sample recovery followed the USEPA method 23 for the
A-60
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determination of emissions of PCDD's and PCDF's from stationary sources (9). A schematic of
the isokinetic sampling train is shown in Figure 5.
Stack wall
Filter
Figure 5. Schematic of isokinetic sampling train
For the first set of experiments (combustion of BrFR laminate), the temperature inside the
stack dropped below 100°C before it even reached the sampling probe. The temperatures below
100°C can lead to condensation inside the stack; therefore, to prevent condensation inside the
stack and ensure proper transport of gaseous organic compounds formed, a heating tape was
wrapped around the stack to maintain the temperature inside the stack between 100°C and 130°C
during combustion. In order to monitor the temperature inside the stack during combustion of the
samples, a thermocouple was placed on the inside wall of the stack right behind the nozzle. Two
other thermocouples were added to the outside wall. Please see Appendix, Table 3 for inside wall
temperature data. Note that for the first set of experiments (BrFR) the cone calorimeter did not
have the heating tape and thermocouples. However, a repeat run was made for the BrFR laminate
which included the heating tape around the stack and thermocouples.
A-61
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Samples tested
Three types of circuit board samples were provided: laminates containing brominated
flame retardant, non-halogen flame retardant (Phosphorous- based) and no-flame retardant. The
laminates were very thin (~0.4mm thick) and contained copper strips. They were made of a
mixture of epoxy resin and e-glass [1]. The three types of circuit board are summarized in Table
1.
Table 1. Circuit Board Types
Circuit Board
types
BrFR
NFR
PFR
Description
Circuit board containing
Brominated Flame
Retardant
Circuit board without
Flame Retardant
Circuit Board containing
Phosphorous Flame
Retardant
Picture
A-62
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Preparation of Samples
Since the laminates provided were too large to be tested as is in the cone calorimeter, the
samples were cut into roughly 100 cm2 square pieces for cone calorimeter testing. Samples were
not conditioned in any way prior to testing. Depending upon how the original laminates were
cut, the samples had 1 or 2 copper strips as shown in Figure 6.
Figure 6. Two-strip and one-strip circuit boards
Initially, it was estimated that 6 thin laminates had to be stacked and burned together in
order to reach a temperature inside the duct of about 120°C during combustion (120°C is the
USEPA method 23 recommended transfer line temperature); this was also the maximum number
of laminates per stack for which the exhaust gas flow rate was sufficient to remove the smoke
produced during combustion (if the number of laminates per stack was increased, smoke came
into the lab). The laminate pieces were selected and configured in six layer stacks where 2 x two-
strip laminates and 4 x one-strip laminates where stacked together. The stacking sequence
ensured that each test sample had the same amount of copper metal in similar configuration.
One single one-strip laminate as well as one single two-strip laminate were also burned
separately to determine the effect of copper on burning patterns and smoke emissions. Each
A-63
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sample was wrapped in aluminum foil such that only the upper side was exposed to the constant
heat flux. The aluminum foil helped to keep the samples together as they burned (preventing
them from falling from the sample holder) and directed the smoke and flames toward the exhaust
hood. Figure 7 shows a sample wrapped in aluminum foil.
Figure 7. Sample wrapped in aluminum foil
Five runs were conducted in series for each circuit board type where the first three runs
consisted of 6- layer samples and the last two runs consisted of 1 one-strip laminate and 1 two-
strip laminate sample. The combustion products for all five runs were collected for a single
analysis for a given type of circuit board. The initial mass of each sample wrapped in aluminum
foil was recorded for each run and is summarized in Table 2. Table 2 also summarizes the
sequence in which the samples were burned.
A-64
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Table 2. Description of Samples
Circuit
Board
Type
BrFR
NFR
PFR
(Repeat
BrFR)
Date
sampled
06/05/08
06/16/08
06/17/08
06/18/08
Run
1
2
3
4
5
1
2
O
4
5
1
2
O
4
5
1
2
O
4
5
Number
of
laminates
6
6
6
1
1
6
6
6
1
1
6
6
6
1
1
6
6
6
1
1
Description (one or two-
strip laminate)
2 two-strip and 4 one-
strip
2 two-strip and 4 one-
strip
2 two-strip and 4 one-
strip
one-strip
two-strip
2 two-strip and 4 one-
strip
2 two-strip and 4 one-
strip
2 two-strip and 4 one-
strip
one-strip
two-strip
2 two-strip and 4 one-
strip
2 two-strip and 4 one-
strip
2 two-strip and 4 one-
strip
two-strip
one-strip
2 two-strip and 4 one-
strip
2 two-strip and 4 one-
strip
2 two-strip and 4 one-
strip
one-strip
two-strip
Sample ID
Br FR Epoxy Laminate, 6
plies, run 1
Br FR Epoxy Laminate, 6
plies, run 2
Br FR Epoxy Laminate, 6
plies, run 3
Br FR Epoxy Laminate, 1
ply, 1 Cu Strip, run 4
Br FR Epoxy Laminate, 1
ply, 2 Cu Strips, run 5
No FR Epoxy Laminate,
6 plies, run 1
No FR Epoxy Laminate,
6 plies, run 2
No FR Epoxy Laminate,
6 plies, run 3
No FR Epoxy Laminate,
1 ply, 1 Cu Strip, run 4
No FR Epoxy Laminate,
1 ply, 2 Cu Strips, run 5
Non Hal FR Epoxy
Laminate, 6 plies, run 1
Non Hal FR Epoxy
Laminate, 6 plies, run 2
Non Hal FR Epoxy
Laminate, 6 plies, run 3
Non Hal FR Epoxy
Laminate, 1 ply, 2 Cu
Strips, run 4
Non Hal FR Epoxy
Laminate, 1 ply, 1 Cu
Strip, run 5
Br FR Repeat run 1
Br FR Repeat run 2
Br FR Repeat run 3
Br FR Repeat run 4
Br FR Repeat run 5
A-65
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Sampling
The cone calorimeter experiments were conducted on a FTT Dual Cone Calorimeter
following the ASTM E-1354-04 method at one heat flux (50 kW/m2), but some modifications
were made to the method: the isokinetic sampling system was added to sample the exhaust gas
and the heating tape was wrapped around the duct for the NFR, PFR, BrFR and BrFR (repeat)
r\
samples. A constant heat flux of 50 kW/m was maintained by setting the cone temperature at
about 759°C. Samples were tested in triplicate without frame and grid, with the back side of each
sample wrapped in aluminum foil and an exhaust flow was maintained at 15 L/s. All samples
were tested copper side up [3]. The initial and final ambient conditions during the combustion of
samples were recorded and are summarized in Table 3.
Table 3. Ambient conditions during experiment
Temperature (°C)
Humidity (%)
Pressure (mbar)
BrFR
Initial
26.5
46
1088
Final
27.5
45
1088
NFR
Initial
26.5
33
1084
Final
NA
32
1084
PFR
Initial
24
35
1091
Final
28
29
1089
BrFR (repeat)
Initial
24
35
1087
Final
24
34
1086
Each sample was ignited and allowed to burn until the flames disappeared. For the 6-
layer Non Hal FR Laminate run 2 and 3, and Br FR Laminate repeat run 3, the flame had to be
re-ignited shortly after initial ignition. The burning times for each sample as well as the initial
mass, mass burnt and volumes of gas sampled were recorded and are summarized in Table 4.
A-66
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Table 4. Data taken during Combustion of Samples
Sample ID
Br FR Epoxy Laminate, 6 plies, run 1
Br FR Epoxy Laminate, 6 plies, run 2
Br FR Epoxy Laminate, 6 plies, run 3
Br FR Epoxy Laminate, 1 ply, 2 Cu Strips, run 5
Br FR Epoxy Laminate, 1 ply, 1 Cu Strip, run 4
No FR Epoxy Laminate, 6 plies, run 1
No FR Epoxy Laminate, 6 plies, run 2
No FR Epoxy Laminate, 6 plies, run 3
No FR Epoxy Laminate, 1 ply, 2 Cu Strips, run 5
No FR Epoxy Laminate, 1 ply, 1 Cu Strip, run 4
Non Hal FR Epoxy Laminate, 6 plies, run 1
Non Hal FR Epoxy Laminate, 6 plies, run 2
Non Hal FR Epoxy Laminate, 6 plies, run 3
Non Hal FR Epoxy Laminate, 1 ply, 2 Cu Strips,
run 4
Non Hal FR Epoxy Laminate, 1 ply, 1 Cu Strip,
run 5
Br FR Repeat run 1
Br FR Repeat run 2
Br FR Repeat run 3
Br FR Repeat run 4
Br FR Repeat run 5
Starting
mass
(g)
61.8
62.2
60.4
11.9
10.2
61.5
64.5
63.8
12.6
11.0
63.3
64.3
64.5
12.6
11.0
61.64
60.03
61.25
10.65
12.15
Mass
lost
(g)
19.2
18.5
17.6
2.5
2.8
16.6
15.9
17.6
3.4
3.5
14.3
14.9
13.8
2.2
2.8
19.1
18.5
18.7
1.3
3.4
Total
sampling
time (s)
426
400
374
99
89
512
622
534
129
110
670
668
652
179
145
360
300
300
60
60
Volume
sampled
(ft3)
10.1
12.4
13.9
10.5
Comments
No heating
tape around
cone
calorimeter
duct
Heating
tape
Heating
tape; Run 2
and 3 were
re-ignited
after 4 min
Heating
tape; Run 3
was re-
ignited
after 1 min
All conditions during the combustion of the samples and collection of organic compounds are
summarized in Table 5.
A-67
-------
Table 5. Summary of Conditions during Combustion of Samples
Parameters
Heat Flux (kW/m2)
Stack Gas Flow Rate (L/s)
Sampling Flow Rate (L/s)
Pump Flow Rate (L/s)
Probe Temperature (°C)
Filter Temperature (°C)
Cold Box Temperature (°C)
Cone Temperature (°C)
Conditions
50
15
0.1104
0.1104
120
120
<20
759
Extraction and Analysis
After sampling, Container No. 1 (filter), Container No. 2 (soot deposited in the nozzle,
transfer probe and front half of filter holder as well as all the methylene chloride and acetone
rinses), Container No. 3 (same material as container No. 2 with toluene as the rinse solvent), and
an another container containing the XAD-2 and glass wool were sealed and recorded on a chain
of custody form. All containers were sent to the EPA Research Triangle Park laboratory for
extraction and analysis.
The EPA Research Triangle Park laboratory received the samples from UDRI and
confirmed them against the chain of custody form. The samples had been spiked at UDRI with
PCDD/F pre-sampling spikes to confirm the sampling process. The samples were spiked again
just before extraction with PBDD/F surrogates and internal standards for both the PCDD/F and
A-68
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PBDD/F. The samples were then extracted with methylene chloride for 3.5 hours and then with
toluene overnight. The cooler methylene chloride extraction is used in low light conditions to
extract the majority of the brominated compounds due to concerns that they could degrade due to
light exposure, the higher extraction temperature of toluene, and longer extraction times. The
toluene extraction procedure was used to ensure that the standard method of extraction (EPA
Method 23 for Dioxin Analysis) was also completed. After extraction, the extracts were
concentrated with a Snyder column and then filtered. The final volume was 1 milliliter. The
extracts were very dark so only one quarter of the extract was used for further clean-up and
analysis. Equal portions of the methylene chloride and toluene extracts were combined and
diluted with hexane for the clean-up. The extracts were then processed through acidic, neutral,
and basic silica gel, and then adsorbed onto basic alumina and washed with dilute methylene
chloride in hexane. The target compounds were then transferred to carbon/celite with 50/50
methylene chloride/hexane, washed with benzene/ethyl acetate and then eluted from the carbon
celite with toluene. The final fraction was concentrated to 100 microliter and analyzed with high
resolution gas chromatography/high resolution mass spectrometry [10].
The samples were analyzed using an isotope dilution method where isotopically labeled
internal standards and surrogate standards were incorporated prior to sampling and extraction.
The surrogate standards were spiked prior to sampling and their recoveries gave a measure of the
sampling process efficiency. The internal standards were spiked prior to extraction and allowed
quantifying the PCDD/Fs and PBDD/Fs present in the samples. According to the USEPA
method 23, recoveries of the pre-extraction standards must be between 40 and 130 percent for
tetra- through hexachlorinated compounds and 25 to 130 percent for the hepta- and
A-69
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octachlorinated homologues. All recoveries for PCDD/Fs pre- sampling surrogate standards must
be between 70 and 130 percent [9]. Percent recovery limits for PBDD/Fs are not available at the
moment. Overall, it was found that PCDD/Fs pre-sampling and pre-extraction surrogate standard
recoveries fell within the acceptable range (see Appendix 2 for recoveries data). Standard
19
recoveries never fell below the lowest limit, but for the isotopes 13C 2,3,7,8 - TeCDF in the
BrFR run and 13 C12 1,2,3,4,7,8,9 - HpCDF in the PFR run, the percent recovery was slightly
above the highest limit, which means that there was a possibility of breakthrough in the sampling
train.
A blank run sample was also analyzed for PCDD/Fs and PBDD/Fs analysis to demonstrate that
no contamination was contributed by laboratory instruments (see Appendix 2 for data).
RESULTS AND DICUSSION
CO/COi production/ Oi consumption data
The gas sampled in the sampling ring was analyzed by a CO/CO2/O2 detector which
allowed measurement of CO/CO2 production rates and C>2 consumption rate as a function time.
The total production rates and consumption rates per initial sample mass are presented in Table
6. Note that for the repeat run for BrFR samples, CO/CO2/O2 data is not provided because it is
not affected by the temperature of exhaust duct.
A-70
-------
Table 6. Total CO/CO2 production rate and C>2 consumption rate data
Sample ID
Br Epoxy Laminate, 6 plies, run
1
Br Epoxy Laminate, 6 plies, run
2
Br Epoxy Laminate, 6 plies, run
3
Br Epoxy Laminate, 1 ply, 2 Cu
Strips, run 5
Br Epoxy Laminate, 1 ply, 1 Cu
Strip, run 4
No FR Epoxy Laminate, 6 plies,
run 1
No FR Epoxy Laminate, 6 plies,
run 2
No FR Epoxy Laminate, 6 plies,
run 3
No FR Epoxy Laminate, 1 ply,
2 Cu Strips, run 5
No FR Epoxy Laminate, 1 ply,
1 Cu Strip, run 4
Non Hal FR Epoxy Laminate, 6
plies, run 1
Non Hal FR Epoxy Laminate, 6
plies, run 2
Non Hal FR Epoxy Laminate, 6
plies, run 3
Non Hal FR Epoxy Laminate, 1
ply, 2 Cu Strips, run 4
Non Hal FR Epoxy Laminate, 1
ply, 1 Cu Strip, run 5
Total CO2
produced (g)
23.7
23.4
20.3
8.0
6.9
35.9
39.3
37.4
14.6
14.2
29.2
31.7
30.0
13.0
11.2
Total CO2
produced (g)/
starting mass
(g)
0.4
0.4
0.3
0.7
0.7
0.6
0.6
0.6
1.2
1.3
0.5
0.5
0.5
1.0
1.0
Total O2
consumed
(g)
18.3
17.9
15.1
2.9
2.3
26.6
28.6
28.1
5.4
5.3
20.5
22.5
21.0
3.7
3.3
Total CO
produced (g)
2.7
2.5
2.6
0.8
0.7
1.4
2.3
1.7
1.0
1.2
2.7
2.7
2.7
1.4
1.5
A-71
-------
PCDD/Fs and PBDD/Fs Data
For each type of circuit board laminates, combustion product samples from five runs
were combined and analyzed to determine total dioxin concentration. The emission levels of
Polychlorinated Dibenzo-p-Dioxins and DibenzoFurans (PCDD/Fs) are reported using both ng
per Kg of laminate and as ng- Toxic equivalent (TEQ) per Kg of laminate. The TEQ
concentration expresses the overall toxicity of a dioxin mixture relative to the toxicity of 2,3,7,8
TeCDD. Each dioxin congener is assigned a toxic equivalent factor (TEF) value based on its
relative toxicity to the toxicity of 2,3,7,8- TeCDD [11]. The WHO 2005 TEF values for all 7
dioxin and 10 furan chemical compounds analyzed are presented in Table 7 [12].
Table 7. Toxic Equivalent Factors of Chlorinated Congeners
Isomer.
2,3,7,8 - TeCDD
1,2,3,7,8 -PCDD
1,2,3,4,7,8 -HxCDD
1,2,3,6,7,8 -HxCDD
1,2,3,7,8,9 -HxCDD
1,2,3,4,6,7,8 -HpCDD
1,2,3,4,6,7,8,9 - OCDD
2,3,7,8 - TeCDF
1,2,3,7,8 -PCDF
2,3,4,7,8 - PCDF
1,2,3,4,7,8 -HxCDF
1,2,3,6,7,8 -HxCDF
2,3,4,6,7,8 - HxCDF
1,2,3,7,8,9 -HxCDF
1,2,3,4,6,7,8 -HpCDF
1,2,3,4,7,8,9 -HpCDF
1,2,3,4,6,7,8,9 - OCDF
2005 WHO (Mammals/Humans)
Toxicity Equiv.
Factor
1
1
0.1
0.1
0.1
0.01
0.0003
0.1
0.03
0.3
0.1
0.1
0.1
0.1
0.01
0.01
0.0003
A-72
-------
The total TEQ was calculated by summing the multiplication of each congener
concentration in the flue gas by its corresponding TEF. The congener concentration (in ng/kg)
was calculated from the data obtained from the HRGC/HRMS analysis (in ng/train) and based on
the basis of total sampling as shown:
/ng\
Concentration —
\kg)
Total flow rate in duct Total congener in extract (ng/train)
x
Flow through sampling line Initial mass of circuit board (kg")
Congeners concentrations below the limit of detection were regarded as zero and reported as less
than limit of detection (
-------
Table 8. Results showing PCDD/Fs concentration in ng- Toxic equivalent (TEQ) per Kg of
laminate in the emission samples from combustion of circuit board samples
Isomer.
2,3,7,8 - TeCDD
1,2,3,7,8 -PCDD
1,2,3,4,7,8 -HxCDD
1,2,3,6,7,8 -HxCDD
1,2,3,7,8,9 -HxCDD
1,2,3,4,6,7,8 -HpCDD
1,2,3,4,6,7,8,9 - OCDD
2,3,7,8 - TeCDF
1,2,3,7,8 -PCDF
2,3,4,7,8 - PCDF
1,2,3,4,7,8 -HxCDF
1,2,3,6,7,8 -HxCDF
2,3,4,6,7,8 - HxCDF
1,2,3,7,8,9 -HxCDF
1,2,3,4,6,7,8 -HpCDF
1,2,3,4,7,8,9 -HpCDF
1,2,3,4,6,7,8,9 - OCDF
Total TEQ (ng/kg)
TEQ (ng/kg)
PFR Epoxy
laminate
-------
Table 9. Results showing PCDD/Fs concentration (in ng/Kg of laminate) in the emission samples
from combustion of circuit board samples
Isomer.
2,3,7,8 - TeCDD
1,2,3,7,8 -PCDD
1,2,3,4,7,8 -HxCDD
1,2,3,6,7,8 -HxCDD
1,2,3,7,8,9 -HxCDD
1,2,3,4,6,7,8 -HpCDD
1,2,3,4,6,7,8,9 - OCDD
2,3,7,8 - TeCDF
1,2,3,7,8 -PCDF
2,3,4,7,8 - PCDF
1,2,3,4,7,8 -HxCDF
1,2,3,6,7,8 -HxCDF
2,3,4,6,7,8 - HxCDF
1,2,3,7,8,9 -HxCDF
1,2,3,4,6,7,8 -HpCDF
1,2,3,4,7,8,9 -HpCDF
1,2,3,4,6,7,8,9 - OCDF
Total cone, (ng/kg)
Cone, (ng/kg)
PFR Epoxy
laminate
-------
The results obtained from the analysis of emissions for PBDD/Fs concentrations in the
extracts are presented in Table 10. For the PFR laminates and NFR laminates, no brominated
congener was detected. The OcBDD and OcBDF compounds were not reported for all circuit
boards types because OcBDD/F needed separate clean-up and the 13Ci2 labeled OcBDD
surrogate standard did not elute from the carbon column during extraction procedure. The data
for the BR FR laminates BrFR (first run and repeat run) were consistent. For the first set of
experiments, it was found that 3213.8 ng PBDD/Fs per kg of laminates was produced. For the
repeat run, it was found that 3389.7 ng PBD/Fs per kg of laminates was produced. No published
data on PBDD/Fs concentrations in ng per kg of combustible material burned where found to
compare the results.
A-76
-------
Table 10. Results showing PBDD/Fs concentration (in ng/Kg of laminate) in the emission
samples from combustion of circuit board laminates
Isomer.
2,3,7 TrBDD*
2,3,7 TrBDF*
2,3,7,8 TeBDD
2,4,6,8 TeBDF
2,3,7,8 TeBDF
1,2,3,7,8 PeBDD
1,2,3,7,8 PeBDF
2,3,4,7,8 PeBDF
1,2,3,4,7,8/1,2,3,6,7,8 HxBDD
1,2,3,7,8,9 HxBDD
1,2,3,4,7,8 HxBDF
1,2,3,4,6,7,9 HpBDD*7**
1,2,3,4,6,7,8 HpBDD*7**
1,2,3,4,6,7,8 HpBDF
OcBDD
OcBDF
Total cone, (ng/kg)
Concentration (ng/kg)
PFR Epoxy
laminate
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
NR
NR
-
BRFR
Epoxy
laminate
24.4
ND
112.4
172.3
855.4
ND
325.1
163.7
ND
ND
107.5
ND
ND
1453.0
NR
NR
3213.8
BR FR Epoxy
laminate, repeat
run
ND
ND
88.7
173.0
536.6
ND
300.1
112.3
ND
ND
96.1
ND
ND
2082.9
NR
NR
3389.7
NFR Epoxy
laminate
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
NR
NR
-
*Not present in the standard; assignment based on isotope theoretical ratios and retention times of matching internal
standards and native congeners; quantified based on concentration of the congeners of the same bromination level
present in the standard
"Assignment based on the elution order of HpCDD congeners on the DBS column.
ND= not detected
NR= not reported (OcBDD/F would need separate clean-up; 13C OcBDD did not elute from carbon column)
A-77
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Heat release data and fire behavior
The combined cone calorimeter heat release data are shown in Table 11. Data for the 6-
ply laminate stacks was not reproducible in all aspects of heat and smoke release due to erratic
physical effects of burning, which are described below. Data from single ply laminates with one
or two strips was also difficult to compare to each other, since the amount of copper metal had
some effects on the amount of heat released. It should be noted that for the repeat run for BrFR,
heat release data and fire behavior are not provided as they are not impacted by heating of the
exhaust duct.
A-78
-------
Table 11. Combined Heat Release Rate data
Description
Br Epoxy Laminate, 6 plies, ran 1
Br Epoxy Laminate, 6 plies, ran 2
Br Epoxy Laminate, 6 plies, ran 3
Br Epoxy Laminate, 1 ply, 2 Cu Strips, ran 5
Br Epoxy Laminate, 1 ply, 1 Cu Strip, ran 4
No FR Epoxy Laminate, 6 plies, ran 1
No FR Epoxy Laminate, 6 plies, ran 2
No FR Epoxy Laminate, 6 plies, ran 3
No FR Epoxy Laminate, 1 ply, 1 Cu Strip, ran 4
No FR Epoxy Laminate, 1 ply, 2 Cu Strips, ran 5
Non Hal FR Epoxy Laminate, 6 plies, ran 1
Non Hal FR Epoxy Laminate, 6 plies, ran 2
Non Hal FR Epoxy Laminate, 6 plies, ran 3
Non Hal FR Epoxy Laminate, 1 ply, 2 Cu Strips, ran 4
Non Hal FR Epoxy Laminate, 1 ply, 1 Cu Strip, ran 5
Sample
Thickness
(mm)
3.1
2.9
3.0
0.4
0.5
3.1
3.3
3.2
0.5
0.6
3.1
3.2
3.2
0.5
0.5
Time
to
ignition
(s)
12
14
13
8
10
14
15
17
13
15
190
190
206
17
15
Peak
HRR
(kW/m2)
242
204
237
171
185
173
177
196
379
265
152
134
222
104
231
Time
to
Peak
HRR
(s)
178
222
208
20
25
240
250
288
24
50
262
326
230
29
29
Time
to
Peak
HRR
-Tig
(s)
166
208
195
12
15
226
235
271
11
35
72
136
24
12
14
Average
HRR
(kW/m2)
68
69
63
53
43
79
72
80
97
81
64
72
74
46
62
Starting
Mass
(g)
61.9
62.2
60.4
11.9
10.2
61.5
64.5
63.8
11.0
12.6
63.3
64.3
64.5
12.6
11.0
Total
Mass
Loss
(g)
19.2
18.5
17.6
2.5
2.8
16.6
15.9
17.6
3.5
3.4
14.3
14.9
13.8
2.2
2.8
Weight
%
Lost
(%)
31.0
29.8
29.1
21.0
27.4
27.0
24.6
27.6
31.9
27.0
22.6
23.2
21.4
17.4
25.5
Total
Heat
Release
(MJ/m2)
23.8
23.4
19.6
3.8
3.2
35.5
37.9
37.5
7.2
7.4
27.1
30.0
28.0
4.9
4.5
Total
smoke
Release
(m2/m2)
2394
2019
2046
449
424
1401
1350
1310
329
353
1310
1336
1209
283
276
Avg.
Effective
Heat of
Comb.
(MJ/kg)
12.35
12.63
11.06
15.12
10.94
21.40
23.83
21.37
19.98
21.46
18.90
20.13
20.33
22 22
15.47
MAHRE
(kW/m2)
93
75
68
83
76
96
85
88
138
111
57
59
59
41
63
FIGRA
1.36
0.92
1.14
8.55
7.39
0.72
0.71
0.68
15.77
5.29
0.58
0.41
0.96
3.58
7.96
A-79
-------
Along with the heat release data in Table 11, the heat release rate curves are plotted in
Figures 8-10. Each of the laminates had their own fire behavior which is described separately
below.
Brominated FR Epoxy Laminate Fire Behavior
For the 6-ply laminate stacks, the only reproducible part of the heat release phenomena
was the initial ignition and the detection of the 1st HRR peak, given the observed fire behavior of
these samples this correlates nicely. Each of the 6 ply laminate stacks, upon exposure to the
cone heater, began to smoke within 10 seconds of heat exposure, and then the samples quickly
foamed up as a large bubble and ignited. This rapid ignition flashed off quickly and then died
back with some edge burning on the top ply, followed by a decrease in heat release. Then the
underlying material began to ignite which led to a 2n FtRR peak. These flames continued to
grow until all of the remaining plies foamed up and flames began to come out from the sides of
the sample. This rapid flare up led to the final FtRR peak between 150 and 250 seconds as
shown in Figure 8. After this rapid flare up the flames began to die down and eventually the
sample extinguished. One sample (FtRR-3) actually self extinguished after the 1st FtRR peak and
reignited after a brief delay (Figure 8 left), again attesting to the physical effects of burning
laminate stacks which led to irreproducibility in the HRR curves. Final chars were primarily
glass laminate with blackened metal strips. Some soot/char was present on the lower laminates,
but the top laminate was a light grey in color and had very little soot/char carbon present. Due to
the sample foaming late in the fire, the shutters of the cone calorimeter could not be closed at the
end of the test - otherwise the shutters would have crushed the sample residue which would have
A-80
-------
led to a false load cell (weight loss) result which would have affected many other cone
calorimeter measurements. So, after the last flame went out, the sample was allowed to stay
under the cone heater for another 60 seconds to collect good baseline data. This change in
procedure is noteworthy since it may have burned off the residual carbon on the top ply of the
burned laminates since for the single ply laminates, carbon char was found after the sample
extinguished. Another thing to note for these samples is that, after ignition and once the flames
had grown sufficiently, wherever the sample was burning next to copper, the flames were a
bright blue in color, typical for burning of copper salts. The flame color was yellow to orange
where there was no copper.
For the single ply laminates (Figure 9 left) the observed behavior of burning was different
than that observed with the 6 ply laminate stacks. Upon exposure to the cone heater, the sample
rapidly began to smoke, and then quickly foamed up and ignited. The flames grew quickly in
intensity and then rapidly extinguished as the epoxy in this thin sample burned away. Final chars
were black with carbon/soot noted along with blackened Cu metal strips. There does appear to
be some slight difference in FtRR behavior for the single and 2 Cu metal strip laminates in that
the single Cu strip sample has two peaks of HRR while the double Cu strip sample has only 1
peak of FIRR. As described above, blue flames were seen where the sample was burning next to
the Cu metal strips.
No Flame Retardant Epoxy Laminate Fire Behavior
The fire behavior of laminates with no flame retardant (control) in the cone calorimeter
was very different than that observed for the brominated flame retardant samples. First of all,
A-81
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none of the laminates (either 6 ply or single ply) foamed up upon exposure to the cone heater.
Instead, the laminates had a strong tendency to warp and bend up towards the cone heater with
snapping and popping heard right before ignition. This behavior was so pronounced for the 6-
ply laminates that the cone calorimeter shutters could not be closed when the sample
extinguished as the laminate plies had curled up into the space where the shutters would
normally close.
Fire behavior of the 6-ply laminates with the non-flame retardant epoxy began with
smoke being released shortly after exposure to the heat source (about 12 seconds after start of
test) followed shortly thereafter by ignition of the sample. Some blue flames (of lesser blue
color intensity than that seen with the brominated FR epoxy laminates) were observed, but for
the most part the color of the flames were orange-yellow with some smoke/soot observed at all
times. As with the brominated 6-ply stacks, the 6-ply stacks of non-FR epoxy showed
irreproducible fire behavior as the top ply would ignite, settle down in heat release/flame
intensity, and then the second ply underneath would ignite. Sometimes the top ply would
provide sufficient insulation to delay ignition of the underlying plies (see FtRR-2 and FtRR-3 in
Figure 8 right) and in other cases the top ply would deform so much that most of the underlying
2n ply would be exposed to the cone heater. With all these physical effects of burning, the FtRR
data for this sample showed a lot more scatter different HRR curve shape, as can be seen in
Figure 9 (right). The FtRR peak occurred when the bottom 4 plies would finally all ignite at
once, leading to a slow rise in heat release followed by a slow steady decrease in HRR
whereupon the sample finally extinguished. The final chars from these 6-ply laminates showed
very little carbon char; just some soot and the blackened/oxidized copper metal strips.
A-82
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For the single ply no FR epoxy laminates (Figure 9, right), the samples smoked, began to
pop and deform (as seen with the 6 ply laminates) and then rapidly ignited and burned out. No
blue flames were observed for these samples when they were burning. As with the 6 ply
laminates, the shutters could not be closed at the end of the test due to laminate deformation.
The final chars were the same as those observed with the 6-ply laminate stacks, with only
fiberglass and blackened metal remaining. Unlike with the single ply brominated FR epoxy
laminate FtRR data, there is a lot more difference in FIRR behavior of 1 Cu metal strip and 2 Cu
metal strip HRR data for the non-halogenated FR epoxy laminates (Figure 9 right), but the
reason for this major difference is not clear since the observed fire behavior was very similar for
both samples. A likely explanation though is that the amount of Cu metal on the surface affected
the amount of surface available for burning and pyrolysis.
Non-Halogenated Flame Retardant Epoxy Laminate Fire Behavior
Fire behavior for the non-halogenated flame retardant epoxy laminates (assumed to be
phosphorus-based flame retardant) was different than the other two types of epoxy laminates.
Phosphorus-based flame retardants in epoxies tend to be condensed phase char formation
systems, so that when they burn they convert the carbon-based epoxy "fuel" into graphitic-type
protective chars which slow down the rate of mass loss and heat release. Indeed, this type of
behavior was observed for the 6-ply laminate stacks, as the samples did ignite rapidly after
exposure to the cone heater, but they then extinguished and did not re-ignite for another 150
seconds after the 1st initial ignition (see Figure 10 left). When these laminate stacks were
exposed to the cone heater, they smoked and made crackling/popping sounds (caused by
A-83
-------
delamination) within 10 seconds of exposure to the cone heater. Shortly after that, they ignited,
but then the flames died down quickly and the flame went out. The spark igniter was reinserted
and eventually the sample reignited. The sample deformed and curled up towards the cone
heater towards the end of the test such that the shutters could not be closed at the end of the test.
During the burning of the sample, no blue flames were observed, only yellow/orange flames with
smoke were seen. At the edges of the sample and towards the end of the test some white colors
could be seen at the bottom of the flame, which confirms the presence of phosphorus-based
flame retardants. The final chars were black, but the fiberglass could be seen through this black
char, which was more than just soot. The copper metal strips were completely blackened. As
with the other 6-ply laminate stack data, due to the physical effects during burning, the HRR
curve shapes were not very reproducible, but the times to ignition and flameout were
reproducible within the cone calorimeter test % error of about 10%.
For the single ply laminates, the effect of the copper strips was more pronounced than
that seen with the other samples. The sample with only one copper strip rapidly burned off while
the sample with two copper strips did not burn as intensely and took a little longer to burn.
Otherwise the fire behavior of this sample was very similar to that of the 6 ply laminate stacks,
with the sample smoking and cracking right before ignition, and the laminate curling up towards
the cone heater by the end of the test [1].
A-84
-------
Brominated FR Epoxy Laminates
With Copper Strips - 6 Ply Stack
No FR Epoxy Laminate 6 ply stack HRR
200
ISO
inn-
er
E
i
400
Time (s)
Sample extinguished (HRR-3) Sample reignited (HRR-3)
300 400
Time (s)
Figure 8. HRR for 6 ply Br Flame Retardant Epoxy Laminate Stacks (left) and No Flame
Retardant Epoxy Laminate Stacks (right).
Br FR Epoxy Laminate I ply stack HRR
No FR Epoxy Laminate 1 ply stack HRR
HRR1 ply! Cu strip
HRR 1 ply 2 Cu Strip
HRR 1 ply 1 Cu Strip
HRR 1 ply 2 Cu Strip
140
Figure 9. FtRR for 1 ply Br Flame Retardant Epoxy Laminates (left) and 1 ply No Flame
Retardant Epoxy Laminates (right).
A-85
-------
Non-Hal FR Epoxy Laminate 6 ply stack HRR
Non-Hal FR Epoxy Laminate 1 ply stack HRR
250
200-
150
HRR1 plyl Cu strip
HRR1 ply 2 Cu strip
100-
200
Figure 10. HRR for 6 ply Phosphorous based Flame Retardant Epoxy Laminate Stacks (left) and
HRR for 1 ply Phosphorous based Flame Retardant Epoxy Laminates (right).
Conclusion
Laminates' Fire Behavior and Heat Release Data
There are four major conclusions that can be made about these samples from the observed
physical fire behavior and from the recorded heat release/smoke release measurements:
1) The 6 ply laminate samples showed erratic HRR behavior due to the physical effects of
laminates igniting and curling/foaming/charring at different rates from stack to stack, even
with the same material. This type of behavior would be normal for a non-coherent stack of
A-86
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laminates which would have nothing adhering them together and instead would have air gaps
between each ply to allow for additional heat release and secondary fire events to occur.
2) 6-ply laminates showed lower peak HRR compared to single ply laminates. The likely
reason for this is that the underlying laminates pull some heat away from the top laminate
which makes the 6 ply stack act a little bit more like a thermally thick sample than a
thermally thin sample like the single ply laminates. However, it is well known that for the
cone calorimeter that sample thickness affects heat release results, and therefore it is not
surprising that the peak HRR is higher for the single ply laminates when compared to the 6-
ply laminate stacks.
3) The amount of Cu metal on the surface appears to have a slight effect on time to ignition.
The more Cu metal present, the more likely that time to ignition will be delayed by a few
seconds. This makes sense as the Cu metal can reflect some heat energy back, and, can
conduct some of the heat energy out and away from the epoxy laminate. However, the 2-3
second delay in time to ignition, while seen in all of the samples, isn't significant in regards
to overall fire behavior of these materials. Once the single ply laminates ignite, they rapidly
go to peak HRR and then extinguish as the fuel is rapidly burned off.
4) Since peak HRR and moment specific data is difficult to compare between samples due to
physical effects of burning, it is better to look at total HR and total smoke when comparing
between samples. By doing this the following trends appear: Brominated FR epoxy has
highest smoke release and lowest total heat release. The non-FR epoxy control has the
highest heat release and middle-level smoke release. The non-halogenated FR epoxy has the
lowest smoke release (although similar to the non-FR epoxy) and middle level total heat
release.
A-87
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Since the purpose of these experiments was to generate a total amount of material to burn for
emissions testing, the total smoke and total heat release data indicate that the experiments were
in general a success and that all experiments done did yield a controlled amount of burning
material. So while individual specimens tested may not correlate exactly in regards to specific
moments of heat release, the total amount of fuel burned/smoke released from specimen to
specimen did correlate well, indicating that the cone calorimeter did provide controlled burning
specimens over a total amount of sampling time. This is important for the emissions testing
since the sampling is done over the total amount of sample burned rather than a specific moment
in time of burning [1].
PCDD/Fs andPBDD/Fs emission data
No significant concentrations of PCDD/Fs were found after sampling and analysis of emissions
from the combustion of BrFR laminates containing brominated flame retardant, PFR laminates
containing non-halogen flame retardant (Phosphorous- based), and NFR laminates containing
no-flame retardant. Most targets pollutants were found to be below the limit of detection of the
analysis. The targets that were detected appeared to be a carry over from a standard. The results
obtained from the analysis of emissions for PBDD/Fs concentrations in the extracts confirmed
the presence of pollutants for the combustion of BrFR laminates containing brominated flame
retardant. The laminates contained copper strips which could have promoted the formation of
dioxins in the emissions. No published data on PBDD/Fs concentrations in ng per kg of
combustible material burned was found to compare the results of this study. For the PFR
laminates and NFR laminates, no PBDD/F congener was detected.
A-88
-------
REFERENCES
[1] Morgan, Alexander B. Cone Calorimeter Analysis of Circuit Board Laminates.
(Personal communication, March 2009)
[2] Fire Protection Engineering. http://www.wpi.edu/Academics/Depts/Fire/Lab/Cone/
[3] ASTM E1354 "Standard Heat Method for Heat and Visible Smoke Release Rates for
Materials and Products Using an Oxygen Consumption Calorimeter"
[4] "ISO/FDIS 5660-1 Reaction-to-fire tests - Heat release, smoke production and mass
loss rate - Part 1: Heat Release (cone calorimeter method)" and "ISO/FDIS
5660-2 Reaction-to-fire tests - Heat release, smoke production and mass loss rate
- Part 2: Smoke production rate (dynamic measurement)"
[5] Babrauskas, V. Specimen Heat Fluxes for Bench-scale Heat Release Rate Testing.
Fire and Materials 1995, 19, 243-252.
[6] Babrauskas, V.; Peacock, R. D. Heat Release Rate: The Single Most Important Variable in
Fire Hazard. Fire Safety Journal 1992, 18, 255-272.
[7] Duggan, G. J.; Grayson, S. J.; Kumar, S. "New Fire Classifications and Fire Test Methods for
the European Railway Industry" . Flame Retardants 2004 Proceedings, January 27-28,
2004, London, UK, Interscience Communications
[8] Apex Instruments. Isokinetic Source Sampler (500-Series models), Operator's
Manual.
[9] USEPA Method 23 "Determination of Polychlorinated Dibenzo-p-dioxins and
Polychlorinated Dibenzofurans from Municipal Waste Combustors"
[10] Tabor, Dennis. Summary of extraction and analysis procedure (personal communication,
March 2009).
A-89
-------
[11] WHO, Environmental Health Criteria 205, 1998
[12] WHO. The 2005 World Health Organization Reevaluation of Human and Mammalian
Toxic Equivalency Factors For Dioxins and Dioxin-Like Compounds. Toxicological
Sciences. 93(2), 223-241 (2006;.
APPENDIX I: SAMPLING DATA
Table 1.
Note: All masses are in grams
Mass of cap+container
Mass of cap+container+water (pre -sampling)
Mass of cap+container+water (post-sampling)
(pre-sampling water) - (post-sampling water)
Mass of cap+container
Mass of cap+container+silica gel (pre-sampling)
Mass of cap+container+silica gel (post-sampling)
Mass of water absorbed in silica gel
Mass of cap+container
Mass of cap+container+XAD
Mass of XAD (pre-sampling)
Petri dish
Petri dish+filter (pre-sampling)
Mass of filter (pre-sampling)
Mass of container+cap
Mass of container+cap+filter (post-sampling)
Mass of filter (post-sampling)
Mass of soot
BFR
209.44
309.78
309.11
0.67
68.15
269.06
271.06
2
207.9
247.99
40.09
68.24
68.66
0.42
209.88
210.38
0.5
0.08
NFR
209.87
311.95
310.3
1.65
68.17
268.16
270.75
2.59
209.02
249.09
40.07
68.23
68.65
0.42
209.13
209.62
0.49
0.07
PFR
207.68
308.24
307.36
0.88
68.15
268.04
270.93
2.89
208.61
248.95
40.34
68.23
68.64
0.41
207.49
207.99
0.5
0.09
BFR
(repeat)
209.53
282.99
282.06
0.93
68.15
268.35
270.18
1.83
209.05
249.05
40
68.23
68.65
0.42
208.61
NA
NA
NA
Table 2.
Soot formed (g)
Mass burned (g)
soot formed/mass
burned (g/g)
BFR
0.08
10.1
0.00792
NFR
0.07
12.4
0.00565
PFR
0.09
13.9
0.00647
BFR (repeat)
NA
10.5
NA
A-90
-------
Table:
Run
1
Run
2
Run
3
Run
4
Run
BFR REPEAT
Time
(h:m:s)
0:00:00
0:01:44
0:02:44
0:03:36
0:04:30
0:05:20
0:06:09
0:09:34
0:09:44
0:10:44
0:11:44
0:12:36
0:13:45
0:14:46
0:17:17
0:17:46
0:18:16
0:19:16
0:20:18
0:21:32
0:22:30
0:26:40
0:27:01
0:27:23
0:27:57
0:31:07
Inside Wall
temperature
95
104
124
134
122
116
110
103
107
111
127
133
121
116
107
109
109
119
131
126
118
108
111
114
113
107
Mass „
, . Comments
(g)
61.3
57.4 ignition
52.1
44.6 max temp
43
42.5
42.2 removed
59.8
58.4 ignition
56.2
49.3
43.4 max temp
41.8
41.3 removed
61
59.8 ignition
59.2 re-ignited
54.7
46.8 max temp
42.8
42.3 removed
10.4
9.9 ignition
7.8 max temp
9.1 removed
11.9
PFR
Time
(h:m:s)
0:00:00
0:03:00
0:05:00
0:06:00
0:07:15
0:08:30
0:09:15
0:10:15
0:11:45
0:13:40
0:16:35
0:17:37
0:19:10
0:20:10
0:21:10
0:22:25
0:23:36
0:24:36
0:25:36
0:27:03
0:28:31
0:30:56
0:33:45
0:34:57
0:36:36
0:37:25
0:39:03
0:40:23
0:41:45
0:42:50
0:44:35
0:46:32
0:49:12
0:49:42
0:50:20
0:52:49
0:55:30
Inside Wall
temperature
96
95
108
128
130
121
115
110
106
105
102
101
100
117
123
130
128
119
113
109
107
105
102
104
102
107
130
127
118
112
109
107
104
114
114
109
105
Mass
(g)
63.2
61.9
60.3
55.3
50.5
48
47.6
47
46.6
46
63.8
63.1
62.1
59.4
57.3
52.5
48.9
47.9
47.3
46.7
46.4
45.8
64.2
63.2
62
60.6
53.1
49.4
48.3
47.9
47.4
46.8
10.6
8.4
7.7
7.2
12.5
Comments
max temp
removed
ignition
re-ignited
max temp
removed
ignition
re-ignited
max temp
removed
no flame
removed
A-91
-------
5
0:31:20
0:31:42
0:32:00
110
114
113
10.6
8.5
8.5
max temp
removed
0:57:00
0:57:39
0:58:29
113
113
110
9.7
10.1
10
no flame
removed
NFR
Time
(h:min:sec)
0:05:31
0:07:00
0:08:23
0:10:00
0:10:55
0:11:47
0:12:51
0:16:09
0:18:09
0:19:19
0:20:32
0:21:30
0:22:55
0:23:58
0:25:09
0:26:18
0:27:44
0:30:46
0:31:46
0:32:45
0:34:06
0:35:06
0:36:41
0:37:30
0:38:44
0:40:08
0:43:39
0:44:00
0:44:22
0:44:58
0:45:52
0:49:16
0:49:32
0:50:06
0:51:00
0:51:48
Inside Wall
temperature
(°Q
118
127
132
122
117
114
112
107
113
120
129
131
125
120
116
113
111
107
111
111
126
131
134
128
121
116
109
121
124
120
116
111
112
123
117
114
Mass (g)
61.1
50.5
46.5
45.1
44.7
44.3
43.8
64.2
61.7
58.6
54.3
50.3
47.8
47.1
48.4
47.4
46.2
63.6
62
61.2
58.5
54.4
50.6
46.1
45.7
44.8
10.8
8
7.1
6.9
6.8
12.1
11
8.5
8.6
8.3
Comments
max temp
removed
max temp
no flame
removed
max temp
no flame
removed
max temp
removed
max temp
removed
A-92
-------
Additional Comments
NFR: Stack conditions after experiment:
Outside Wall temperature: 167°C
Inside Wall temperature: 112°C
PFR: Stack conditions after experiment:
Outside Wall temperature: 155°C and 162°C (2 thermocouples on outside wall)
Inside Wall temperature: 74°C
BFR REPEAT : Stack conditions after experiment:
Outside Wall temperature: 158°C and 164°C (2 thermocouples on outside wall)
Inside Wall temperature: 96°C
APPENDIX 2: ANALYSIS DATA
PCDD/Fs:
Pre-extraction surrogate recovery limits:
13C12-2MCDF
13C12-2MCDD
13C12-2,4DCDF
13C12-2,7DCDD
13C12-2,4,8 TrCDF
13C12-2,3,7,8TeCDF
13C12-2,3,7,8TeCDD
13C12- ,2,3,7,8 PCDF
13C12- ,2,3,7,8 PCDD
13C12- ,2,3,6,7,8 HxCDF
13C12- ,2,3,6,7,8 HxCDD
13C12- ,2,3,4,6,7,8 HpCDF
13C12- ,2,3,4,6,7,8 HpCDD
13C12- ,2,3,4,6,7,8,9 OCDD
Surrogate Recovery limits (range in %)
25.0
25.0
25.0
25.0
25.0
25.0
25.0
40.0
40.0
40.0
40.0
40.0
40.0
25.0
130
130
130
130
130
130
130
130
130
130
130
130
130
130
A-93
-------
Pre- sampling surrogate recovery limits:
13C12-2,8-DCDF
13C12-2,3-DCDD
13C12-2,3,7-TrCDD
37C14-2,3,7,8-TeCDD
13C12-2,3,4,7,8-PCDF
13C12-l,2,3,4,7,8-HxCDF
13C12-l,2,3,4,7,8-HxCDD
13C12-l,2,3,4,7,8,9-HpCDF
Pre Spike Recovery Limits (range in %)
70.0
70.0
70.0
70.0
70.0
70.0
70.0
70.0
130
130
130
130
130
130
130
130
BR FR Epoxy Laminate:
Sampled: 6/05/08
Extracted: 7/15/08
Acquired: 01/27/09
Sample description/Narrative: Sample Rerun; Elevated Standard Recoveries are due to a large
interferentpeak causing reduced signal on the TeCDD Recovery Standard.
Pre Extraction
Surrogates
13C12-2,3,7,8 TeCDF
13C12-2,3,7,8 TeCDD
13C12-1,2,3,7,8 PCDF
13C12-1,2,3,7,8 PCDD
13C12-l,2,3,6,7,8HxCDF
13C12-l,2,3,6,7,8HxCDD
13C12-1,2,3,4,6,7,8
HpCDF
13C12-1,2,3,4,6,7,8
HpCDD
13C12-1,2,3,4,6,7,8,9
OCDD
%
Recovery
135.0
125.9
108.6
93.4
68.7
65.3
59.6
78.6
67.3
Pass or
Fail
recovery
limits
F
P
P
P
P
P
P
P
P
A-94
-------
Pre-Sampling
Surrogates
37C14-2,3,7,8-TeCDD
13C12-2,3,4,7,8-PCDF
13C12-1,2,3,4,7,8-
HxCDF
13C12-1,2,3,4,7,8-
HxCDD
13C12-1,2,3,4,7,8,9-
HpCDF
%
Recovery
91.3
91.8
108.1
112.9
112.7
Pass or
Fail
recovery
limits
P
P
P
P
P
Isomer.
2,3,7,8 - TeCDD
1,2,3,7,8 - PCDD, co-elution
1,2,3,4,7,8 -HxCDD, co-
elution
1,2,3,6,7,8 -HxCDD
1,2,3,7,8,9 -HxCDD
1,2,3,4,6,7,8 -HpCDD
1,2,3,4,6,7,8,9 - OCDD
2,3,7,8 - TeCDF
1,2,3,7,8 -PCDF
2,3,4,7,8 - PCDF
1,2,3,4,7,8 -HxCDF
1,2,3,6,7,8 -HxCDF
2,3,4,6,7,8 - HxCDF
1,2,3,7,8,9 -HxCDF
1,2,3,4,6,7,8 -HpCDF
1,2,3,4,7,8,9 -HpCDF
1,2,3,4,6,7,8,9 - OCDF
ng/train
0.029
0.095
0.113
0.103
0.113
0.196
0.231
0.03
0.064
0.064
0.032
0.029
0.036
0.04
0.084
0.064
0.131
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
2005 WHO
(Mammal/Humans
) Toxicity Equiv.
Factor
1
1
0.1
0.1
0.1
0.01
0.0003
0.1
0.03
0.3
0.1
0.1
0.1
0.1
0.01
0.01
0.0003
TEQ
ng/train
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00084
0.00000
0.00000
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible
Concentration
LOD=Limit of Detection
Total TEQ
ng/train
0.0008
A-95
-------
NFR Epoxy Laminate:
Sampled: 6/16/08
Extracted: 7/15/08
Acquired: 12/15/08
Sample description/Narrative: All detected targets appear to be carry over from a Standard.
Pre Extraction
Surrogates
13C12-2,3,7,8TeCDF
13C12-2,3,7,8TeCDD
13C12-1,2,3,7,8 PCDF
13C12-1,2,3,7,8 PCDD
13C12-l,2,3,6,7,8HxCDF
13012-1,2,3,6,7,8 HxCDD
13C12-1,2,3,4,6,7,8
HpCDF
13C12-1,2,3,4,6,7,8
HpCDD
13C12-1,2,3,4,6,7,8,9
OCDD
%
Recovery
88.1
88.0
97.4
101.8
75.9
73.6
67.9
85.1
72.4
Pass or
Fail
recovery
limits
P
P
P
P
P
P
P
P
P
Pre-Sampling
Surrogates
37C14-2,3,7,8-TeCDD
13C12-2,3,4,7,8-PCDF
13C12-1,2,3,4,7,8-
HxCDF
13C12-1,2,3,4,7,8-
HxCDD
13C12-1,2,3,4,7,8,9-
HpCDF
%
Recovery
90.0
100.9
104.2
111.1
115.5
P
P
P
P
P
A-96
-------
Isomer.
2,3,7,8 - TeCDD
1,2,3,7,8 - PCDD, co-elution
1,2,3,4,7,8 - HxCDD, co-elution
1,2,3,6,7,8 -HxCDD
1,2,3,7,8,9 -HxCDD
1,2,3,4,6,7,8 -HpCDD
1,2,3,4,6,7,8,9 - OCDD
2,3,7,8 - TeCDF
1,2,3,7,8 -PCDF
2,3,4,7,8 - PCDF
1,2,3,4,7,8 -HxCDF
1,2,3,6,7,8 -HxCDF
2,3,4,6,7,8 - HxCDF
1,2,3,7,8,9 -HxCDF
1,2,3,4,6,7,8 -HpCDF
1,2,3,4,7,8,9 -HpCDF
1,2,3,4,6,7,8,9 - OCDF
ng/train
0.013
0.015
0.024
0.022
0.024
0.06
0.096
0.036
0.014
0.014
0.018
0.016
0.02
0.022
0.028
0.025
0.063
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
2005 WHO
(Mammals/Humans)
Toxicity Equiv.
Factor
1
1
0.1
0.1
0.1
0.01
0.0003
0.1
0.03
0.3
0.1
0.1
0.1
0.1
0.01
0.01
0.0003
TEQ
ng/train
0.00000
0.00000
0.00000
0.00000
0.00000
0.00060
0.00003
0.00360
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00028
0.00000
0.00000
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible Concentration
LOD=Limit of Detection
Total TEQ
ng/train
0.0045
PFR Epoxy Laminate:
Sampled: 06/17/08
Extracted: 07/15/08
Date Acquired: 12/15/08
Sampled description/ Narrative: All detected targets appear to be carry over from a Standard.
A-97
-------
Pre Extraction
Surrogates
13C12-2,3,7,8TeCDF
13C12-2,3,7,8TeCDD
13C12-1,2,3,7,8 PCDF
13C12-1,2,3,7,8 PCDD
13C12-l,2,3,6,7,8HxCDF
13C12-l,2,3,6,7,8HxCDD
13C12-1,2,3,4,6,7,8
HpCDF
13C12-1,2,3,4,6,7,8
HpCDD
13C12-1,2,3,4,6,7,8,9
OCDD
%
Recovery
90.0
89.4
109.9
110.9
70.4
69.2
64.4
80.2
72.5
Pass or
Fail
recovery
limits
P
P
P
P
P
P
P
P
P
Pre-Sampling
Surrogates
37C14-2,3,7,8-TeCDD
13C12-2,3,4,7,8-PCDF
13C12-1,2,3,4,7,8-
HxCDF
13C12-1,2,3,4,7,8-
HxCDD
13C12-1,2,3,4,7,8,9-
HpCDF
%
Recovery
105.3
115.5
119.9
128.5
135.2
Pass or
Fail
recovery
limits
P
P
P
P
F
A-98
-------
Isomer.
2,3,7,8 - TeCDD
1,2,3,7,8 - PCDD, co-elution
1,2,3,4,7,8 - HxCDD, co-elution
1,2,3,6,7,8 -HxCDD
1,2,3,7,8,9 -HxCDD
1,2,3,4,6,7,8 -HpCDD
1,2,3,4,6,7,8,9 - OCDD
2,3,7,8 - TeCDF
1,2,3,7,8 -PCDF
2,3,4,7,8 - PCDF
1,2,3,4,7,8 -HxCDF
1,2,3,6,7,8 -HxCDF
2,3,4,6,7,8 - HxCDF
1,2,3,7,8,9 -HxCDF
1,2,3,4,6,7,8 -HpCDF
1,2,3,4,7,8,9 -HpCDF
1,2,3,4,6,7,8,9 - OCDF
ng/train
0.012
0.015
0.025
0.023
0.025
0.036
0.047
0.024
0.013
0.013
0.014
0.013
0.016
0.018
0.015
0.02
0.047
LOD
LOD
LOD
LOD
LOD
LOD
LOD
EMPC
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
2005 WHO
(Mammals/Humans)
Toxicity Equiv.
Factor
1
1
0.1
0.1
0.1
0.01
0.0003
0.1
0.03
0.3
0.1
0.1
0.1
0.1
0.01
0.01
0.0003
TEQ
ng/train
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00240
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible Concentration
LOD=Limit of Detection
Total TEQ
ng/train
0.0024
BR FR Epoxy Laminate repeat run:
Sampled: 06/18/08
Extracted: 07/15/08
Acquired: 12/09/08
Sampled description/ Narrative: All detected targets appear to be carry over from a Standard.
A-99
-------
Pre Extraction
Surrogates
13C12-2,3,7,8TeCDF
13C12-2,3,7,8TeCDD
13C12-1,2,3,7,8 PCDF
13C12-1,2,3,7,8 PCDD
13C12-l,2,3,6,7,8HxCDF
13C12-l,2,3,6,7,8HxCDD
13C12-1,2,3,4,6,7,8
HpCDF
13C12-1,2,3,4,6,7,8
HpCDD
13C12-1,2,3,4,6,7,8,9
OCDD
%
Recovery
109.5
114.9
112.3
110.2
52.2
56.6
47.9
55.4
49.2
Pass or
Fail
recovery
limits
P
P
P
P
P
P
P
P
P
Pre-Sampling
Surrogates
37C14-2,3,7,8-TeCDD
13C12-2,3,4,7,8-PCDF
13C12-1,2,3,4,7,8-
HxCDF
13C12-1,2,3,4,7,8-
HxCDD
13C12-1,2,3,4,7,8,9-
HpCDF
% Recovery
96.4
100.9
120.5
126.4
127.2
Pass or Fail
recovery
limits
P
P
P
P
P
A-100
-------
Isomer.
2,3,7,8 - TeCDD
1,2,3,7,8 - PCDD, co-elution
1,2,3,4,7,8 - HxCDD, co-elution
1,2,3,6,7,8 -HxCDD
1,2,3,7,8,9 -HxCDD
1,2,3,4,6,7,8 -HpCDD
1,2,3,4,6,7,8,9 - OCDD
2,3,7,8 - TeCDF
1,2,3,7,8 -PCDF
2,3,4,7,8 - PCDF
1,2,3,4,7,8 -HxCDF
1,2,3,6,7,8 -HxCDF
2,3,4,6,7,8 - HxCDF
1,2,3,7,8,9 -HxCDF
1,2,3,4,6,7,8 -HpCDF
1,2,3,4,7,8,9 -HpCDF
1,2,3,4,6,7,8,9 - OCDF
ng/train
0.036
0.036
0.052
0.036
0.056
0.092
0.172
0.072
0.06
0.06
0.084
0.076
0.1
0.116
0.14
0.132
0.22
LOD
2005 WHO
(Mammals/Humans)
Toxicity Equiv.
Factor
1
1
0.1
0.1
0.1
0.01
0.0003
0.1
0.03
0.3
0.1
0.1
0.1
0.1
0.01
0.01
0.0003
TEQ
ng/train
0.00000
0.03600
0.00520
0.00360
0.00560
0.00092
0.00005
0.00720
0.00180
0.01800
0.00840
0.00760
0.01000
0.01160
0.00140
0.00132
0.00007
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible Concentration
LOD=Limit of Detection
Total TEQ
ng/train
0.1188
Blank run:
Sampled: 05/29/08
Extracted: 07/15/08
Acquired: 01/27/09
Sample Description/ Narrative: sample rerun.
A-101
-------
Pre Extraction
Surrogates
13C12-2,3,7,8TeCDF
13C12-2,3,7,8TeCDD
13C12-1,2,3,7,8 PCDF
13C12-1,2,3,7,8 PCDD
13C12-l,2,3,6,7,8HxCDF
13C12-l,2,3,6,7,8HxCDD
13C12-1,2,3,4,6,7,8
HpCDF
13C12-1,2,3,4,6,7,8
HpCDD
13C12-1,2,3,4,6,7,8,9
OCDD
%
Recovery
90.6
86.3
78.5
79.8
73.6
72.2
66.1
86.0
77.1
Pass or
Fail
recovery
limits
P
P
P
P
P
P
P
P
P
Pre-Sampling
Surrogates
37C14-2,3,7,8-TeCDD
13C12-2,3,4,7,8-PCDF
13C12-1,2,3,4,7,8-
HxCDF
13C12-1,2,3,4,7,8-
HxCDD
13C12-1,2,3,4,7,8,9-
HpCDF
%
Recovery
100.9
112.8
118.4
122.2
109.2
Pass or
Fail
recovery
limits
P
P
P
P
P
A-102
-------
Isomer.
2,3,7,8 - TeCDD
1,2,3,7,8 - PCDD, co-elution
1,2,3,4,7,8 -HxCDD, co-
elution
1,2,3,6,7,8 -HxCDD
1,2,3,7,8,9 -HxCDD
1,2,3,4,6,7,8 -HpCDD
1,2,3,4,6,7,8,9 - OCDD
2,3,7,8 - TeCDF
1,2,3,7,8 -PCDF
2,3,4,7,8 - PCDF
1,2,3,4,7,8 -HxCDF
1,2,3,6,7,8 -HxCDF
2,3,4,6,7,8 - HxCDF
1,2,3,7,8,9 -HxCDF
1,2,3,4,6,7,8 -HpCDF
1,2,3,4,7,8,9 -HpCDF
1,2,3,4,6,7,8,9 - OCDF
ng/train
0.026
0.043
0.061
0.056
0.061
0.129
0.152
0.029
0.033
0.033
0.033
0.03
0.036
0.041
0.036
0.048
0.113
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
LOD
2005 WHO
(Mammals/Humans)
Toxicity Equiv.
Factor
1
1
0.1
0.1
0.1
0.01
0.0003
0.1
0.03
0.3
0.1
0.1
0.1
0.1
0.01
0.01
0.0003
TEQ
ng/train
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
0.00000
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible Concentration
LOD=Limit of Detection
Total TEQ
ng/train
ND
PBDD/Fs:
BR FR Epoxy Laminate:
Sampled: 6/05/08
Extracted: 7/16/08
Acquired: 02/17/09
A-103
-------
Pre Extraction
Surrogates
13C237TrBDD(IS)
13C2378TeBDD(IS)
13C 1 23678 HxBDD (IS)
13C 123789 HxBDD (IS)
13COcBDD(IS)
13C2468TeBDF(DSSP)
13C12378PeBDD(DSSP)
%
Recovery
87.0
56.4
115.1
96.3
NR
123.7
127.9
Isomer
237 TrBDD*
237 TrBDF*
2378 TeBDD
2468 TeBDF
2378 TeBDF
12378 PeBDD
12378 PeBDF
23478 PeBDF
123478/1 23678 HxBDD
123789 HxBDD
1 23478 HxBDF
1234679 HpBDD*7**
1234678 HpBDD*7**
1 234678 HpBDF
OcBDD
OcBDF
ng/train
0.08
ND
0.37
0.56
2.80
ND
1.06
0.54
ND
ND
0.35
ND
ND
4.76
NR
NR
* not present in the standard; assignment based on isotope theoretical ratios and retention times of matching internal
standards and native
congeners; quantified based on concentration of the congeners of the same bromination level present in the standard
** assignment based on the elution order ofHpCDD congeners on the DB5 column
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible Concentration
LOD=Limit of Detection (S/N=3)
NR=not reported (OcBDD/F would need separate clean-up;13C OcBDD did not elute from carbon
column)
A-104
-------
NFR Epoxy Laminate:
Sampled: 6/16/08
Extracted: 7/16/08
Acquired: 02/17/09
Pre Extraction
Surrogates
13C237TrBDD(IS)
13C2378TeBDD(IS)
13C1 23678 HxBDD (IS)
13C 123789 HxBDD (IS)
13COcBDD(IS)
13C2468TeBDF(DSSP)
13C 12378 PeBDD (DSSP)
%
Recovery
108.9
89.7
132.8
102.4
NR
103.7
113
Isomer
237 TrBDD*
237 TrBDF*
2378 TeBDD
2468 TeBDF
2378 TeBDF
12378 PeBDD
12378 PeBDF
23478 PeBDF
123478/1 23678 HxBDD
123789 HxBDD
1 23478 HxBDF
1234679 HpBDD*7**
1234678 HpBDD*7**
1 234678 HpBDF
OcBDD
OcBDF
ng/train
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
NR
NR
* not present in the standard; assignment based on isotope theoretical ratios and retention times of matching internal
standards and native
congeners; quantified based on concentration of the congeners of the same bromination level present in the standard
** assignment based on the elution order ofHpCDD congeners on the DB5 column
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible Concentration
LOD=Limit of Detection (S/N=3)
NR=not reported (OcBDD/F would need separate clean-up;13C OcBDD did not elute from carbon
column)
A-105
-------
PFR Epoxy Laminate:
Sampled: 06/17/08
Extracted: 07/15/08
Date Acquired: 12/15/08
Pre Extraction
Surrogates
13C237TrBDD(IS)
13C2378TeBDD(IS)
13C1 23678 HxBDD (IS)
13C1 23789 HxBDD (IS)
13COcBDD(IS)
13C2468TeBDF(DSSP)
13C 12378 PeBDD (DSSP)
%
Recovery
79.6
61.1
122.6
116.1
NR
117.6
139.1
Isomer
237 TrBDD*
237 TrBDF*
2378 TeBDD
2468 TeBDF
2378 TeBDF
12378 PeBDD
12378 PeBDF
23478 PeBDF
123478/1 23678 HxBDD
123789 HxBDD
1 23478 HxBDF
1234679 HpBDD*7**
1234678 HpBDD*7**
1 234678 HpBDF
OcBDD
OcBDF
ng/train
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
NR
NR
* not present in the standard; assignment based on isotope theoretical ratios and retention times of matching internal
standards and native
congeners; quantified based on concentration of the congeners of the same bromination level present in the standard
** assignment based on the elution order ofHpCDD congeners on the DB5 column
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible Concentration
LOD=Limit of Detection (S/N=3)
NR=not reported (OcBDD/F would need separate clean-up;13C OcBDD did not elute from carbon
column)
A-106
-------
BR FR Epoxy Laminate repeat run:
Sampled: 06/18/08
Extracted: 07/16/08
Acquired: 02/17/09
Pre Extraction
Surrogates
13C237TrBDD(IS)
13C2378TeBDD(IS)
13C1 23678 HxBDD (IS)
13C 123789 HxBDD (IS)
13COcBDD(IS)
13C2468TeBDF(DSSP)
13C 12378 PeBDD (DSSP)
%
Recovery
77.2
57.1
112.5
120.9
NR
110.5
139.6
Isomer
237 TrBDD*
237 TrBDF*
2378 TeBDD
2468 TeBDF
2378 TeBDF
12378 PeBDD
12378 PeBDF
23478 PeBDF
123478/1 23678 HxBDD
123789 HxBDD
1 23478 HxBDF
1234679 HpBDD*7**
1234678 HpBDD*7**
1 234678 HpBDF
OcBDD
OcBDF
ng/train
ND
ND
0.24
0.47
1.45
ND
0.81
0.30
ND
ND
0.26
ND
ND
5.64
NR
NR
* not present in the standard; assignment based on isotope theoretical ratios and retention times of matching internal
standards and native
congeners; quantified based on concentration of the congeners of the same bromination level present in the standard
** assignment based on the elution order ofHpCDD congeners on the DB5 column
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible Concentration
LOD=Limit of Detection (S/N=3)
NR=not reported (OcBDD/F would need separate clean-up;13C OcBDD did not elute from carbon
column)
A-107
-------
Blank run:
Sampled: 07/15/08
Extracted: 07/16/08
Acquired: 02/17/09
Pre Extraction
Surrogates
13C237TrBDD(IS)
13C2378TeBDD(IS)
13C1 23678 HxBDD (IS)
13C1 23789 HxBDD (IS)
13COcBDD(IS)
13C2468TeBDF(DSSP)
13C 12378 PeBDD (DSSP)
%
Recovery
117.3
93.5
118.1
106.0
NR
105.3
112.1
Isomer
237 TrBDD*
237 TrBDF*
2378 TeBDD
2468 TeBDF
2378 TeBDF
12378 PeBDD
12378 PeBDF
23478 PeBDF
123478/1 23678 HxBDD
123789 HxBDD
1 23478 HxBDF
1234679 HpBDD*7**
1234678 HpBDD*7**
1 234678 HpBDF
OcBDD
OcBDF
ng/train
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
NR
NR
* not present in the standard; assignment based on isotope theoretical ratios and retention times of matching internal
standards and native
congeners; quantified based on concentration of the congeners of the same bromination level present in the standard
** assignment based on the elution order of HpCDD congeners on the DB5 column
ND = not detected
NS= not spiked
EMPC=Est. Max. Possible Concentration
LOD=Limit of Detection (S/N=3)
NR=not reported (OcBDD/F would need separate clean-up;13C OcBDD did not elute from carbon
column)
A-108
-------
FLAME RETARDANTS IN PRINTED CIRCUIT
BOARDS: APPENDIX C
U.S. EPA. Analysis of Circuit Board Samples by
XRF. Original Report - July 28, 2008. Revised
Report - March 23, 2009. Prepared by Arcadis.
A-109
-------
ARCADIS
Infrastructure, environment, facilities Imagine the result
&EPA
Analysis of Circuit Board Samples
byXRF
Report
Original Report - July 28, 2008
Revised Report - March 23, 2009
A-110
-------
ARCADIS
Infrastructure, environment, facilities Imagine the result
DISCLAIMER: The USEPA Design for the Environment Program has provided
additional information in Appendix B and Appendix C to further explain methods
and results. This information is critical for interpreting the main report,
especially in regards to chorine measurements. Results found in the main
report are not complete without the information in the appendices, and cannot
be correctly understood or interpreted without their aid.
A-lll
-------
Analysis of Circuit Board
Samples by XRF
Report
Prepared for:
U.S. Environmental Protection
Agency
Air Pollution Prevention and Control
Division
Research Triangle Park, NC 27711
Prepared by:
ARCADIS
4915 Prospectus Drive
Suite F
Durham
North Carolina 27713
Tel 919.544.4535
Fax 919.544.5690
Our Ref.:
RN990234.0037
This document is intended only for the use
of the individual or entity for which it was
prepared and may contain information that
is privileged, confidential and exempt from
disclosure under applicable law. Any
dissemination, distribution or copying of
this document is strictly prohibited.
A-112
-------
Table of Contents
1. Statement of Work
2. Introduction
3. Experimental
3.1 Sample preparation
3.1.1 Phase 1
3.1.2 Phase 2
3.1.2.1 Sub-sampling
3.1.2.2 Milling
3.1.2.3 Homogenization and sub-sampling
3.1.2.4 Pellet Preparation
3.1.2.5 Preparation of Spiked Sample
3.2 Analysis
3.3 Quantification
4. Data
4.1 Phase 1
4.2 Phase 2
5. Conclusions
115
115
116
116
116
116
116
116
118
118
119
120
120
121
121
122
128
Tables
Table 1: Samples Received
Table 2: Milling parameters
Table 3. Coarse fraction Milling Parameters
Table 4. Pellet Press Parameters
Table 5. Composition of Spiked Sample 7
Table 6. Results for Phase 1 Samples
115
117
118
119
120
121
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Table 7. Elemental Concentrations, weight % 122
Table 8. Sample 7, Short Term Reproducibility, weight % 124
Table 9. Sample Preparation Reproducibility, Sample 7 125
Table 10. Recovery of Spikes, Sample 7, weight % 126
Figures
Figure 1 . Sieved Circuit Board 117
Appendices
Appendix A: Responses to Questions
Appendix B: Laminate Etching and Chlorine Measurements
Appendix C: ISOLA Experiment Demonstrating the Impact of the Etching Process
on Chlorine Measurements
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1. Statement of Work
The following report is in response to a task under Work Assignment (WA) No. 3-37,
that consisted of an elemental analysis of two sets of circuit boards samples by X-ray
Fluorescence (XRF) Spectrometry. This report describes the results of those analyses
and provides discussions of several questions that have arisen from these analyses.
2. Introduction
Under two separate events, described as "Phase 1" and "Phase 2," circuit board
samples were received for analyses. Table 1 presents this information.
Table 1: Samples Received
Laminate
#
1
2
3
4
5
6
7
Phase
1
1
1
2
2
2
2
Laminate
type
NFR
BFR
PFR
HF
HF
HF
HF
NFR : Non-flame Retardant; BFR: Bromine Flame Retardant; PFR: Phosphorous
Flame Retardant; HF: Halogen-free
Each board was received "mostly" free of copper plating. Phase 2 samples were
accompanied by a letter that indicated 12" by 12" samples of "halogen-free laminates."
Inspection of each showed a rectangular area of plated copper in one corner of each
sample that was used to identify each sample. Further inspection showed that some
samples had additional small, random areas of elemental copper. This was also true of
the phase 1 samples.
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3. Experimental
3.1 Sample preparation
3.1.1 Phase 1
As directed, phase 1 samples were cored in the shop at random locations. These
circuit board disks were sized to be a slip fit to our standard sample cups. Separate
disks were cut for each individual analysis.
3.1.2 Phase 2
As agreed prior to sample receipt, samples were homogenized, powdered, pelletized,
and analyzed by XRF. One sample was prepared and analyzed in duplicate. One
spiked sample was prepared and analyzed.
3.1.2.1 Sub-sampling
To minimize the errors of heterogeneity, each board was sub-sampled from several
locations. One board was weighed at ~ 79 g. per square foot. To ensure that any one
sample was of sufficient size to provide sufficient material for sample, replicate, and
spike, it was decided to sample 21-1" diameter locations in a representative manner.
Boards were delivered to the shop, which laid out a 9 by 7 grid. With directions to avoid
potential elemental copper, all edge areas were not sampled. 21 of the remaining 35
positions were sampled by coring.
3.12.2 Milling
The 21 disks from each sample were homogenized by milling. A Spex Certiprep model
6850 Freezer/Mill was used for this step. This instrument is basically a hammer mill
operating at liquid nitrogen temperatures. All 21 disks were added to a sample tube
along with the stainless steel, SS, hammer. This instrument has the capacity to handle
a single sample of this size. Table 2 provides the operating parameters for the first
milling operation.
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Table 2: Milling parameters
Operation
Pre-cool time
# of cycles
Milling time
Re-cool time
Value
15 min.
4
3 min.
10 min.
After samples had warmed back to room temperature, they were opened and
examined. The milling was considered generally acceptable, with a large fraction of the
sample present as powder. A fraction of each sample, however, was present as large
flakes. Figure 1 shows one sample after size classification.
Figure 1 . Sieved Circuit Board
It was unclear whether this coarse flake fraction (left) represented a surface treatment
coating or was merely incomplete milling of a homogeneous sample. After discussions
it was decided to sieve, re-mill the coarse fraction, and combine. A W.S. Tyler Number
18 sieve, Tyler Equivalent 16 mesh, was used for the fractionation. The fine fraction
was transferred to a pre-cleaned 40 ml sample vial while the coarse fraction was
returned to the cryo-mill for further milling. Table 3 provides the operating parameters
for this second milling operation.
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Table 3. Coarse fraction Milling Parameters
Operation
Pre-cool time
# of cycles
Milling time
Re-cool time
Value
10 min.
4
2 min.
5 min.
Less stringent conditions were used since the coarse fraction represented a smaller
sample. Coarse fractions were found to range between ~ 1 g and 3 g. This second
milling operation was successful and the sample fractions were combined.
3.1.2.3 Homogenization and sub-sampling
Sample homogenization began with the coring of multiple discs spanning the area of
each sample. It continued with the cryo-milling operation described in the previous
section. It was finalized just prior to sample weighing by sample riffling. A Humboldt
Mfg. Co. Model H-3971C archeological grade rifflerwas used for this purpose. This
model was designed for samples in the several gram range. A riffler has the purpose of
sub-sampling a larger powdered sample in a statistically equivalent manner that is
particle-size and density independent. It achieves this by fractionating the total sample
through multiple, equivalently sized paths leading to two or more sample buckets. No
assumptions, however, can be made that the sub-samples will remain equivalent if
time is allowed to pass. Riffling must be done immediately prior to sample use.
This riffler is manufactured of SS (stainless steel). It consists of a hopper, a gate,
multiple equivalent alternating vertically angled slots, and two buckets. It may be used
for both homogenization and sub-sampling and was used for both purposes in this
project. The entire sample was passed through the riffler twice. After the second pass,
sample material in one bucket was returned to the sample vial. The sub-sample in the
second bucket represented ~ 4 g at this point. This fraction was passed through the
riffler one more time. Each bucket contained about 2 g, which was the correct size for
preparing a single XRF pellet.
3.12.4 Pellet Preparation
Pellets were prepared by pressing a mixture of powdered sample with a polymeric
binder. 2 grams of sample were weighed and transferred to a boron carbide mortar and
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pestle. The sample was ground for a period, though little grinding took place at this
stage for these samples. 2 ml of Spex Liquid Binder, equivalent to 200 mg of binder in
a dichloromethane carrier, were added using a Gilson Microman positive displacement
pipettor. Sample was mixed until the sample returned to a free-flowing state. Sample
was transferred to 32 mm dies with vacuum port. Pellet was pressed under vacuum in
a Spex 3630 X-press programmable hydraulic press. Table 4 presents the pelletizing
parameters.
Table 4. Pellet Press Parameters
Operation
Applied pressure
Hold time
Release time
Value
20 tons
1.1 min.
1.0 min.
Formed pellets were transferred to Millipore 47 mm Petrislides for identification and
stored in a silica gel controlled desiccator until ready for analysis.
As agreed, one sample was prepared in duplicate. As agreed, one sample was spiked
with known masses during the pellet preparation stage. After discussions with the
work assignment manager and the industry committee, spiking materials and elements
were selected as described in the next section. Based upon data from the first set of
circuit boards; spikes were prepared for aluminum, calcium, and copper.
3.1.2.5 Preparation of Spiked Sample
As directed, one sample was prepared by spiking with known masses of certain
analytes to provide data on recovery. Sample 7 was chosen since that sample
represents the most complete data set. In other words, sample 7 was prepared in
duplicate and analyzed in replicate. This sample had the most data available for
comparison to the spiked sample.
Based upon data from the Phase 1 circuit boards; spikes were prepared for aluminum,
calcium, and copper using reagent grades of AI2O3, CaCO3, and CuSO4, respectively.
This gave us data on a fourth element; S. Table 5 provides data on the preparation of
the spiked sample.
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Table 5. Composition of Spiked Sample 7
Material
Sample 7
AI203
CaCO3
CuSO4
Total
Mass, g
1.761
0.0383
0.1504
0.0505
2.0002
The four materials listed in Table 5 were weighed in the amounts described in Table 5
and mixed manually using mortar and pestle. A pellet was prepared from this mix as
described in the previous section.
3.2 Analysis
Pressed sample pellets were analyzed on a Panalytical model PW2404 wavelength
dispersive X-Ray Fluorescence Spectrometer equipped with the PW2540 sample
changer. The instrument is equipped with both flow and scintillation detectors plus five
crystals. The instrument is controlled and acquires data using the manufacturer's
software, SuperQ. The entire spectrum is acquired as 10 sub-scans using variations in
applied power, crystal, detector, filter material, and goniometer setting.
Data were acquired using the application, IQ+Metalloids. IQ+Metalloids is a variation
of the manufacturer supplied application, Z/Q+. IQ+Metalloids adds 4 channels to
provide increased sensitivity for the elements: arsenic, selenium, mercury, and lead.
The increased sensitivity comes from increased counting times while the goniometer
sits at the peak maxima. Z/Q+ is a full scan application, which optimizes sample
throughput.
3.3 Quantification
Data acquired as above are quantified using the manufacturer supplied software, /Q+.
/Q+ is a matrix independent, fundamental parameters based quantification program.
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4. Data
4.1 Phase 1
Table 6 presents the data for the three Phase 1 samples. Each was analyzed in
duplicate; where each analysis also represents a replicate sample preparation (cores
from different locations on the board). To be explicit, due to sample decomposition
within the instrument, each sample core was analyzed once. During analysis, the
whole-board cores charred. Replicate analysis on charred samples seemed neither
good chemistry nor good for the instrument.
Table 6. Results for Phase 1 Samples
Sample
Element
Na
Mg
Al
Si
P
S
Cl
K
Ca
Ti
Cr
Fe
Cu
As
Br
Sr
Pb
Zr
1-NFR
Mean, %
0.109
0.008
0.083
0.398
0.0016
0.010
0.878
0.0078
2.62
0.061
0.0039
0.036
0.054
0.0008
0.064
0.0007
% RSD
1.76
5.38
31.94
37.02
16.26
14.89
9.91
27.70
10.04
9.09
9.69
1.03
17.32
4.72
30.44
2-BFR
Mean, %
0.01
1.042
0.145
0.0017
0.0081
0.591
0.0043
1.29
0.038
0.033
1.81
0.056
6.13
0.064
0.0088
% RSD
2.34
23.03
60.67
42.27
33.60
25.42
28.74
137.65
27.16
22.53
28.89
3-PFR
Mean, %
0.114
0.0070
0.773
0.201
4.19
0.013
0.517
0.0070
2.49
0.060
0.0044
0.038
3.59
0.0011
0.0047
0.083
0.0007
% RSD
67.47
5.50
8.84
1.75
8.03
11.30
49.55
4.67
4.20
2.30
13.93
12.49
1.08
NFR : Non-flame Retardant; BFR: Bromine Flame Retardant; PFR: Phosphorous
Flame Retardant; HF: Halogen-free
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Results above are the average of duplicate samples; reproducibility is also presented
as % relative standard deviation, % RSD. In Table 6, an empty cell under a Mean
column heading indicates that this element was not detected in either replicate of this
sample. An empty cell under % RSD indicates that the element was only observed in
one of the replicates of that sample.
In examining Table 6, the most striking feature is the very large % RSDs found for
several results. This is true for all three samples. This is attributed to circuit board
heterogeneity.
4.2 Phase 2
Table 7 presents the data acquired under this task. Colored cells represent not
detected elements for the respective samples.
The first pellet (sample 7) was analyzed three times within a 1 hour period to provide
data on short term reproducibility. These data are provided in Table 8.
As directed, one sample was selected for replicate sample preparation and analyses.
These data may be found in Table 9. Here, both "Replicate 1" and "Replicate 2"
represent the mean determinations of triplicate data collections on a single pellet.
The results for sample 7 spiked as described in Table 5 are provided in Table 10. For
comparison the results from replicate preparations of sample 7 are repeated from
Table 9.
Table 7. Elemental Concentrations, weight %
Element
F
Na
Mg
Al
Si
P
S
Cl
K
4
0.135
0.663
2.76
15.65
1.42
0.0104
0.449
0.0161
5
0.143
0.085
5.65
9.23
0.84
0.0050
0.427
0.0126
6
0.121
0.410
6.35
111
0.74
0.0049
0.488
0.0087
7
0.054
0.151
0.375
5.30
10.07
0.68
0.0098
1.044
0.0123
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Element
Ca
Ti
Cr
Fe
Ni
Cu
Zn
Br
As
Sr
Zr
Ba
Pb
4
5.39
0.107
0.0184
0.135
0.0044
0.051
0.0050
0.0616
0.0038
0.00084
5
4.58
0.096
0.0045
0.067
0.041
0.0031
0.0012
0.0627
6
4.47
0.093
0.0058
0.064
0.047
0.0044
0.00071
0.0581
0.0168
7
5.64
0.117
0.0065
0.088
0.056
0.0043
0.0012
0.00116
0.0722
0.00087
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Table 8. Sample 7, Short Term Reproducibility, weight %
Element
F
Na
Mg
Al
Si
P
S
Cl
K
Ca
Ti
Cr
Fe
Ni
Cu
Zn
Br
As
Sr
Zr
Ba
Pb
Rep1
0.148
0.3678
5.305
9.97
0.6837
0.0122
0.9215
0.01335
5.659
0.1199
0.006383
0.09025
0.059
0.00449
0.001292
0.072
Rep 2
0.1447
0.3776
5.253
9.972
0.6793
0.008915
0.8356
0.01237
5.674
0.1182
0.007127
0.09096
0.05484
0.003899
0.001128
0.07354
Rep 3
0.05028
0.1473
0.3834
5.325
10.04
0.6879
0.00974
0.813
0.01404
5.614
0.114
0.006177
0.09163
0.05479
0.00459
0.001084
0.07197
Mean
0.05028
0.146667
0.376267
5.294333
9.994
0.683633
0.010285
0.8567
0.013253
5.649
0.117367
0.006562
0.090947
0.05621
0.004326
0.001168
% RSD
1.19
2.10
0.70
0.40
0.63
16.62
6.68
6.33
0.55
2.59
7.62
0.76
4.30
8.63
9.39
0.072503
0.000619 0.000709 0.001066 0.000798
1.24
29.65
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Table 9. Sample Preparation Reproducibility, Sample 7
Element
F
Na
Mg
Al
Si
P
S
Cl
K
Ca
Ti
Cr
Fe
Ni
Cu
Zn
Br
As
Sr
Zr
Ba
Pb
Replicate 1
0.0503
0.1467
0.3763
5.294
9.994
0.6836
0.01029
0.86
0.0133
5.649
0.11737
0.00656
0.09095
0.05621
0.00433
0.0012
0.07250
Replicate 2
0.0570
0.1558
0.3731
5.302
10.143
0.6713
0.00934
1.23
0.0113
5.625
0.11597
0.00653
0.08504
0.05573
0.00428
0.0012
0.0012
0.07199
Mean
0.0537
0.1513
0.3747
5.298
10.069
0.6774
0.00981
1.04
0.0123
5.637
0.11667
0.00655
0.08799
0.05597
0.00430
0.0012
0.0012
0.07225
0.00080 0.00095 0.00087
% RSD
8.91
4.29
0.60
0.10
1.05
1.29
6.84
25.36
11.40
0.30
0.85
0.32
4.75
0.61
0.74
0.00
0.50
12.38
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Table 10. Recovery of Spikes, Sample 7, weight %
Element
Al
Ca
Cu
S
F
Na
Mg
Si
P
Cl
K
Ti
Cr
Fe
Ni
Zn
Br
As
Sr
Zr
Ba
Pb
Sample 7 Mean
(Table 9)
5.298
5.637
0.05597
0.00981
0.0537
0.1513
0.3747
10.069
0.6774
1.04
0.0123
0.11667
0.00655
0.08799
0.00430
0.0012
0.0012
0.07225
0.00087
Sample 7 Spike
5.193333
8.201
1.019333
0.614233
0.147767
0.293467
8.333
0.5176
0.846133
0.010305
0.100767
0.006422
0.072413
0.004176
0.001184
0.00118
0.066293
0.000601
Mean % Recovery
91
103
97
119
111
89
94
87
92
95
98
111
93
110
115
115
104
78
Recovery % RSD
0.5
0.9
1.3
2
4
0.4
0.5
0.5
8
2
2
15
2
5
0
23
1.2
15
The spiking of a non-blank material provides results that are slightly difficult to interpret.
The spiked material acts as a diluent for all elemental results that are not added as part
of the spiking process. Iron and magnesium in Table 10 are an example of this.
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The proper calculation is described by equations 1 and 2.
%TheoreticalR.Q cov eryt = 100 * -
%analytei * Sample!
100
1]* Spike J
Sample! + ^ Spike j
Equation 1
%SpikeRe cov ery = 100 *
%SpikedSample.
%TheoreticalRe cov ery
Equation 2
Where sample 7 and Spike; refer to the values found in Table 5, %analyte values are
found in the first column of Table 9. GRAVy refers to the gravimetric factor for analyte i
in spike material j.
To be more explicit, one example of Spike; from Table 5 would be AI2O3. The only
analytej in alumina would be aluminum. Therefore, GRAVy in this case would be the
gravimetric factor for aluminum in alumina. The gravimetric factor is a well established
concept in quantitative chemistry and is defined as the molecular weight of the analyte,
Al, divided by the molecular weight of the form it is in, alumina.
2*MW _of _
(2*MW _of_Al + 3 *MW _of_O)
= 0.529527
Table 10 presents these spike recovery data. Spike recovery data are presented in the
final two columns to represent the mean spike recovery and the % variance (based
upon 1 a of triplicate analyses performed on the spiked sample pellet) about that
mean. Fluorine was not observed in the spiked sample despite having been reported in
Tables 7, 8, and 9. As Table 8 demonstrates, fluorine is not dependably quantified at
this level. The values in blue represent those analytes for which spikes were introduced
into the sample. Black values are strictly based upon the dilution effect mentioned
above.
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5. Conclusions
Several conclusions may be observed from the data presented here.
• The Phase 1 sample preparation of cored boards did not provide quality data. This
likely had to do with two aspects. First, these boards are heterogeneous. This can
be seen in the data variability associated with "replicate" samples cored from
different locations on the boards. The second is that the cored boards charred
during analysis. Due to this, we were unwilling to perform replicate analyses on
any of these Phase 1 samples.
• The Phase 2 efforts to achieve homogeneous samples were successful. Sampling
of several aliquots across the circuit boards followed by milling and riffling has
achieved reproducible results. This is observed, in particular, in Table 7 where
replicate samples were prepared.
• From this it may be inferred that the circuit boards are heterogeneous. The
analysis of cored single disks, while the cheaper approach, does not provide
dependable data. This was seen in the phase 1 analyses.
• Pellets prepared from these powdered samples are robust and may be used for
multiple analyses without significant deterioration.
• The cryo-mill is an appropriate approach to powdering this type of sample. Other
mills, hammer and ball mills may also work.
• It is unclear whether the flaked material found after the first milling represents the
effect of surface coating or not. It is also possible that it is the result of samples
larger than desirable for that size sample container on the cryo-mill
• The pellets prepared by the methods described in this memo were of good quality.
However, separation by sieving could have been carried out more extensively and
would have ultimately resulted in pellets that were stronger and more
homogeneous than those achieved during this work.
• Table 8 describes the short term reproducibility achieved for multiple analyses of a
single pellet. The standard deviations described in this table provide one approach
to detection limits by this method.
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Table 10 described the recovery of spiked materials. Four elements were
deliberately spiked during these experiments. Recovery for these spikes is very
good. Copper and calcium, in particular, are excellent at 97 and 103 % recovery.
Aluminum and sulfur at 91 and 121 % are also very good recovery. The low
recoveries for lead are not considered significant since this element was not spiked
and because this element is very close to detection limits. This is seen in Table 8
where %RSD for lead is 30% and the individual analyses are only 6-10ppm.
The results for chlorine are somewhat unclear. Data for this element shows
somewhat more variance than is seen for most other elements. It must be
considered possible that some or all of the chlorine represents contamination from
the Liquid Binder carrier material, dichloromethane. Two steps, mixing the sample
plus binder till it returns to a free flowing state, and operation of the pellet dies
under vacuum, were specifically included as quality assurance steps to minimize
dichloromethane retention. No proof is available either way. This could be
investigated in future work by preparing pellets with both liquid binder and binder
pellets. The latter are solvent free.
However, the Phase 1 chlorine results are also high and variable. No
dichloromethane was used in the preparation of these Phase 1 samples.
When certified standard reference materials are not available for the sample
matrix, spiked samples become the best alternative available. This approach is
highly dependent upon operator experience and attention to detail. Additional
replicates, spiking with other elements would be appropriate for the future.
The submittal letter described these samples as "halogen free laminates". This
data found one or more halogen in each sample. Chlorine was found in all
samples, though the source of that chlorine remains an open question. Separate
from chlorine, however, fluorine was found in 1of 7 samples and bromine in 4 of 7
samples. Laboratory contamination does not appear to be a source for either of
these elements.
During the quantification process, matrix of these boards was described as an
organic polymeric material. This was used as a "balance compound" during
quantification. This was an assumption in the absence of better information. The
data can be re-calculated should this be an invalid assumption.
We have investigated interactions between bromine and arsenic as a result of
questions from the committee. As described in a separate section, it is likely that
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the majority of the arsenic response in the high bromine Phase 1 sample is due to
a bromine interference. As described, two corrective approaches are available that
could be investigated and implemented in future work.
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Appendix A
Appendix A: Responses to Questions
A1. Comments from Draft Version
SS = stainless steel
Yes. The appropriate section has been edited.
Homogenization and Sub-sampling section. Does "several gram range" refer to 2 to 10
grams?
Yes, though it is not that specific. The actual capacity is restricted by the mass
that can be held in the 2 buckets. That varies with the density of the material.
What is the composition of this binder? Would it have any influence of the results?
As described in that section, this binder is composed of a polymer dissolved in
dichloromethane at a concentration of 100 mg of polymer per 1 ml of solution.
The exact composition of the polymer is not provided by the manufacturer, of
course; its elemental composition is based upon carbon, hydrogen, oxygen,
and nitrogen (per the retailer's literature).
As an organic structure, the polymer does not have any specific response by
XRF; though it may contribute in some small fashion to the baseline. We have
found no evidence of elemental contamination from this liquid binder material
and it has been used in this laboratory for many years. As described in
previous communications, the solvent, dichloromethane, could contribute to
the chlorine response...if it remained in the pellet until analysis. Our pellet
preparation procedures are designed to prevent residual dichloromethane in
the prepared pellets.
Are there quality controls associated with this (ZIQ+) analysis? Can you briefly mention
what they are?
On a monthly basis, drift is measured and a correction factor is calculated and
stored. This is based upon the analysis of a manufacturer-supplied drift
standard.
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Appendix A
On a monthly basis, control charts are maintained based upon the analyses of
4 historical standards. These control charts are used to alert personnel to
instrumental problems.
For each analysis by this program identification is based upon a
manufacturer's supplied library of peaks.
Additional quality control is based upon what the customer specifies. This can
include replicate analyses of each pellet or other sample form, analyses of
replicate pellets, homogenization procedures, analyses of standard reference
materials, when available, and preparation and analysis of spiked samples.
For the Phase 2 samples, all of these except standard reference materials
were implemented.
Could you express variability as percent coefficient of variation?
This has been done in the pertinent tables.
Could you provide all the raw data for the replicates in an appendix? Printouts of raw
data from the computer would be fine. Since the final mean value is a mean of two
means, would you agree that expressing the standard deviation or standard error with
the means for replicates 1 and 2 would be appropriate?
This raw data will follow separately.
How was the spiking done? Can you add that to the methods section?
A separate experimental section was implemented for this version of the
report. The description of the spiking process may be found there.
Why did the wt% ofAl not increase with spiking? Ca, S and Cu all increased markedly.
Each additional spiking compound acts as a diluent on the others. As such it is
quite possible for a spiked element to be lower on a concentration basis and
yet be correct.
A-132
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Analysis of Circuit
Board Samples by
XRF
Report
Appendix A
Could you provide the gravimetric factors for the analytes so that myself and the
partners can understand the calculations? Refers to equation 1
An expanded description of gravimetric factors has been added above. They
may also be found in reference books, such as Lange's Handbook of
Chemistry.
Should the %analyte, be expressed as a percent or as a decimal in this equation?
Refers to equation 1
%analyte should be used in the percent form. This is why there is a factor of
100 in the equation.
Why is spike j in the denominator, preceded by a sum sign? I see only one value in
Table 8 (Now table 5). Refers to equation 1
The equation includes a Z because there are 3 spiking compounds added to
the sample. J is the counting integer for the multiple spiking compounds and
varies from 1-3. The summation is correct. Sample 7+1 = 2.002, as the final
row of Table 5 indicates.
Why is this so high? (Refers to sulfur) I understand variability around 100% but does
119% suggest a measurement problem? Similar for Br and As- 115%
While sulfur is an element we are "watching," we are not prepared at this time
to declare that there is a problem needing resolution with this element.
Consider equation 2, where the numerator is based upon experimentally
acquired data from the XRF. Similarly, the denominator of 2 comes from
equation 1 and also includes experimentally acquired data; both XRF and
balance. There is variability in both the numerator and denominator of equation
2 and we would need additional data to be certain biases existed here.
Bromine and arsenic are present at 12 ppm in the unspiked sample. For
arsenic, in particular, this must be considered at the detection limit since it was
observed in only 1 of 2 replicate samples. At this level for these elements,
noise becomes more important and the difference between 100 % and 115 %
cannot be considered significant for a single sample.
A-133
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Analysis of Circuit
Board Samples by
XRF
Report
Appendix A
Conclusions: Could you explain this sentence? The standard deviation describes the
detection limits? Doesn't it describe the variability around the mean?
One definition of detection limit is na; where n is an integer selected based
upon the desired confidence level. To be done properly, detection limits are
measured using dilute samples. In many cases that is shortcut by using the na
calculation.
Conclusions: Where appropriate, could you provide the detection limits, e.g. for lead?
As described in the previous response, this depends upon the confidence level
desired. N = 3 is generally considered a reasonably conservative approach.
Referring to Table 6, short term reproducibility, of the draft report, we can use
a = 0.000237 weight %. 3a then becomes 0.0007 weight % for lead. This is
strictly an estimate that would need to be confirmed experimentally.
Conclusions: Brian etal, could you elaborate your conclusions here ... e.g. Brian
commented that based on the phase I XRF data, these high chlorine levels may be
accurate. Dennis commented that he saw decreasing Cl concentrations as he made
replicate measurements
Simply put, both the range of concentrations and variability are similar between
phase 1 and phase 2 samples. Chlorine in phase 1 samples ranged from 0.5
to 0.9 % and had % RSDs ranging from 10 to 40. Similarly, phase 2 samples
ranged from 0.4 to 1 % while the % RSD of replicate sample preparations was
25 % for sample 7. And, since no binder was used for the phase 1 samples,
there is every indication that the chlorine concentrations observed during
phase 1 are real.
Dennis may be referring to the chlorine data where the replicates could be
exhibiting a decreasing trend with time. This is, however, a small trend, from
0.92 to 0.81 % across triplicate analysis.
All phase 2 samples exceed the "halogen free" definition for chlorine. Sample 7
is simply consistently high across several sample preparations and analyses.
Conclusions: Yes this is correct- can you explain what a "balance compound"is and
how it is used?
A-134
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ARCADIS
Analysis of Circuit
Board Samples by
XRF
Report
Appendix A
In the absence of information about the organic mass present, the material that
is not observed by XRF, the quantification program will assign the full sample
mass to the analytes observed. This will usually result in unacceptably high,
and wrong, results. Informing the program that there is a balance compound
present avoids this.
Bromine-Arsenic Question
In an e-mail dated July 15, 2008, ^^^^^^^B transmitted a communication
from || regarding a potential interference
between bromine and arsenic by XRF. The following figure was prepared by
| from the phase 1 analytical results and was attached to these messages.
Br Vs As in Epoxy Resins
y = 0.0091x
R2 = 0.9978
2345
Br(%)
Figure A-l. Bromine vs. Arsenic in Phase 1 samples
This graph clearly shows a direct relationship between the Phase 1 bromine and
arsenic results. While there are more than one possible explanation for such a causal
A-135
-------
Analysis of Circuit
Board Samples by
XRF
Report
Appendix A
relationship, ^^^^^^^B warns of a spectral interference leading to arsenic false
positives. After investigating the data, there is every indication that he is correct.
The instrument is currently not operational while it awaits the arrival and installation of
a new chiller. If the instrument were up, running several known standards would have
been the most appropriate approach to investigating this potential interference. Since
we do not have that option at the moment, the following several paragraphs consider
the question.
Tables A-1 and A-2 provide information on instrumental operational parameters for the
several sub-scans and channels that were used for these analyses. "LOCorr" is the
acronym for line overlap correction; it is marked yes for the all sub-scans and channels.
While the several acronyms used in these tables are not important; what is important is
that:
• Channel 2 defines the conditions under which the arsenic data was collected
• Sub-scan 3 defines the conditions under which bromine data was collected
• Channel 2 instrumental conditions match those used under sub-scan 3
A-136
-------
ARCADIS
Analysis of Circuit
Board Samples by
XRF
Report
Appendix A
Table A-l. Arsenic and Bromine Scans
Analyte
As
Br
Line
KB
KB1.3
Scan or
channel
Ch2
Sc3
Use
LOCorr
Yes
Yes
Measured
(kcps)
5.539
542.153
LO Corrected
(kcps)
5.539
542.153
Used
(kcps)
5.532
541.46
Calculated
(kcps)
5.532
541.475
Difference
(kcps)
0
-0.016
Table A-2. Line Selection Parameters
Scan or
channel
Sc1
Sc2
Sc3
Sc4
Sc5
Sc6
Sc7
Sc8
Sc9
Sc10
Ch1
Ch2
Ch3
Ch4
X-tal
LIF220
LIF200
LIF220
LIF220
LIF220
LIF200
Ge
PE
PE
PX1
LIF220
LIF220
LIF220
LIF220
Detector
Scint
Scint
Scint
Scint
Duplex
Flow
Flow
Flow
Flow
Flow
Scint
Scint
Scint
Scint
Collimator
(urn)
150
150
150
150
150
150
300
300
300
300
150
150
150
150
Tube
Filter
kV
material / urn
Brass 7100
Brass / 300
None
Al / 200
None
None
None
None
None
None
None
None
Al / 200
Al / 200
60
60
60
60
50
32
32
32
32
32
60
60
60
60
mA
66
66
66
66
80
125
125
125
125
125
66
66
66
66
Start
(°)
14.02
12.02
26.63
42.03
61.03
76.04
91.05
100.1
130.1
20.08
40.35
43.58
45.64
51.65
End
(°)
18.58
20.99
44.98
61.98
126
146
146
114.9
147
59.98
40.35
43.58
45.64
51.65
Step
(°)
0.04
0.03
0.05
0.05
0.05
0.08
0.1
0.12
0.12
0.15
0
0
0
0
A-137
-------
ARCADIS
Analysis of Circuit
Board Samples by
XRF
Report
Appendix A
It is, therefore reasonable to examine the sub-scan 3 data for evidence of spectral
interference. Figure A-2 provides an expanded view of sub-scan 3 in the vicinity of the
arsenic Kp lines. In Figure A-2, we can observe that the bromine Ka1,2 doublet is in
the vicinity of the arsenic Kp lines. The horizontal colored line below the doublet
represents the calculated baseline. The green vertical hashmarks to the right of the
doublet represent predicted arsenic peak locations. As can be seen from the cells at
lower left, the graphic crosshairs are at the arsenic Kp3 line and it can be seen that the
tail of the bromine doublet contributes a non-zero response at this 20 angle. Figure A-3
expands the bromine tail region of this spectrum.
1 ] 2 3 4 ] 5 I 6 ] 7 ] 8 9 | 10 ]
[CIRCUITBOARD IS405 FRONT]
41.0 42.0
PW2404 XRF spectrometer
J
Y: 112.194 kcps X||g| A|
Line: |As" |R§3 Orderfi
Recipe: |ERA Sample par.: lolid Compounds X: 43.616* Y: 12.194 kcps
Figure A-2. Sub-scan 3, Bromine doublet
A-138
-------
ARCADIS
Analysis of Circuit
Board Samples by
XRF
Report
Appendix A
0
43.40
Line: |fe~ |m Ordec|T~ [H59 %
43.50
43.60
43.70
43.81
Figure A-3. Bromine Tail in Arsenic Region
Having said that there is spectral overlap of bromine on arsenic, just as |
| noted, we must also note that Table A-2 says that line overlap correction is
used. Having said that, we must also note that the arsenic response in the LO Corr cell
is identical to the measured value, which would seem to contradict that.
Examining Figure A-3 it looks a lot as if the 5.539 kcps measured value in Table A-2
comes from the difference between the calculated background at the crosshair and the
bromine tail response. The question remains as to whether or not corrective
procedures have been implemented. The Panalyticalsoftware provides 2 approaches
to corrective action that are applicable to interferences. One is the already mentioned
line overlap correction. The other is a line specific, as opposed to sub-scan specific,
background correction procedure. Details on these procedures are not available to the
operator within the /Q+ quantification program.
While the details of such applications as IQ+Metalloids are not available through the
/Q+ program, they can be found via the Setup program. Here we can find that channel
2, arsenic, was set up without any background points. Four are available to provide
from 0th to 4th order regressions of curved backgrounds in the vicinity of an analytical
A-139
-------
Analysis of Circuit
Board Samples by
XRF
Report
Appendix A
channel. By using the channel set button on the bottom of the application specific
page, one arrives at a graphic representation of the appropriate standard. On this
page, there is a box for defining line overlap interferences. For arsenic in the
IQ+Metalloids application no line overlaps are defined.
In summary, the above suggests there is a strong probability that an uncorrected
bromine interference on arsenic exists in this application. Once the instrument is back
up, the new chiller is installed, running of standards while modifying the application;
followed by re-running certain samples would be appropriate.
There are two comments to be made on this subject
• The applications that are currently on this instrument were set up by the
manufacturer's representative during installation of the software
• As noted in the last few paragraphs, the operator does not have easy access to
such details as background correction and line overlap correction.
A-140
-------
Analysis of Circuit
Board Samples by
XRF
Report
Appendix B
Appendix B: Laminate Etching and Chlorine Measurements
Both phase 1 and phase 2 samples were sent directly from each manufacturer to
David Bedner at ISOLA. Mr. Bedner prepared the laminates for the experiments by
etching a portion of the copper from the laminate using standard methods and
procedures.
To prepare the copper clad laminates for etching, 33% of the copper was masked with
an acrylic tape and 66% of the copper was left exposed. Standard Cupric Chloride
solution (2.5% Normal, 130°F) was then applied to the laminate using a Chemcut
Etcher model GSK-168 with a line speed of 1.5 feet per minute. Thirty-three percent of
each sample's copper surface remained intact after etching. Once etching was
complete, the samples were sent to the appropriate laboratory for combustion testing
and XRF analysis.
Laminate suppliers certified that the supplied pre-preg samples met the IPC's halogen
free definition of less than 900 ppm chlorine (Table B-1). However, the etching
process described above caused residual chlorine to be left on the laminates, as
demonstrated by a subsequent experiment conducted by ISOLA (Appendix C). As a
result, the measured chlorine levels noted in Tables 6 and 7 of the report should be
considered in the context of the procedures used to etch the laminates. Furthermore,
elemental composition was measured using XRF analysis, which some partners view
as less quantitative than other methods. In addition, phase 1 samples were not
homogenized prior to analysis, whereas phase 2 samples were homogenized.
Dichloromethane was used during homogenization, but specific steps were taken to
prevent the samples from retaining any dichloromethane.
A-141
-------
Analysis of Circuit
Board Samples by
XRF
Report
Appendix B
Table B-1. Laminate suppliers' independent chlorine analyses
Sample Number
Chlorine concentration in the laminate
based upon suppliers analysis by an
independent third party
Not provided
317 ppm
Method : 1C
290 ppm
Method: 1C
265 ppm
Method: 1C
Due to this information, which was discovered after original preparation of the report,
DfE would like to alter the tenth conclusion bullet in the report as following (page 15,
second bullet):
"The results for chlorine are higher than predicted based on halogen free definitions
(<900 ppm chlorine) and are likely due to contamination with chlorine during the
etching process when the laminates were prepared. Data for this element also shows
somewhat more variance than is seen for most other elements. A second possibility of
chlorine contamination was the Liquid Binder carrier material, dichloromethane used
for phase 2 sample preparation. Two steps, mixing the sample plus binder till it returns
to a free flowing state, and operation of the pellet dies under vacuum, were specifically
included as quality assurance steps to minimize dichloromethane retention. Chlorine
results for Phase 1 laminates, where no homogenization was done and therefore no
dichloromethane was used, are also high and variable. Therefore, chlorine
contamination likely came from the etching process. To demonstrate this Mr. Bedner
did an experiment comparing chlorine levels of laminates prepared in three different
ways. Results are shown in Appendix C."
A-142
-------
Analysis of Circuit
Board Samples by
XRF
Report
Appendix C
Appendix C: ISOLA Experiment Demonstrating the Impact of the Etching
Process on Chlorine Measurements
Samples of two laminates, one with a brominated flame retardant and one with a flame
retardant that was not brominated, were each prepared one of three ways: 1) copper
was peeled from the laminate, i.e. no etching, 2) copper was etched from the laminate
using the standard method described in Appendix B or 3) copper was etched from the
laminate using the standard method described in Appendix B, followed by an additional
de-ionized water rinse before analysis. Chlorine content was analyzed using XRF and
results were reported as relative chlorine content compared to known quantity of
bromine or another element (proprietary). The results are shown in the Tables and
Figures below. Standard etching resulted in 7-9 times more chlorine compared to un-
etched laminate whereas additional water rinsing yielded only 2-3 times more chlorine
than the un-etched laminate.
Laminate manufacturers typically measure elemental concentrations by 1C and believe
this is the most accurate method for determining element levels. XRF was chosen for
this experiment for the objective of determining general differences in composition
between laminate samples, to aid in choosing a diverse set of laminates for Phase II
experiments.
XRF measurement
16533-1
BrFR No Etch
Average
16533-2
BrFR Normal Etch
Average
16533-3
BfFR Extra Rinse
Average
16533-4
PFR No Etch
Average
Br
96.85
95.98
94.69
95.84
75.20
71.05
69.30
71.85
95.47
89.25
90.31
91.68
Cl
3.15
4.02
5.31
4.16
24.80
28.95
30.70
28.15
4.53
10.75
9.69
8.32
2.27
4.63
2.13
3.01
X
72.57
68.57
72.41
71.18
A-143
-------
ARCADIS
Analysis of Circuit
Board Samples by
XRF
Report
Appendix C
16533-5
PFR Normal Etch
Average
16533-6
PFR Extra Rinse
Br
Cl
21.41
16.55
13.07
17.01
7.54
7.23
8.81
7.86
X
56.73
61.49
62.12
60.11
59.80
58.63
58.51
58.98
Chlorine Pick-up from Etcher
•p n AE* -,
& 04 -
o n ^c; -
n ^ -
c n i^ -
° 02-
u. lo •
ai
^ n n^; -
nj u.uo
& ° H
n
• non-Bromine
1 — 1
II II II
No etch Normal Extra No etch Normal Extra
etch rinse etch rinse
Sample Conditions
Bromine Samples
non-Bromine
Samples
Cl pick "normal"
9x
7x
Cl pick up X-Rinse
2x
3x
A-144
-------
FLAME RETARDANTS IN PRINTED CIRCUIT
BOARDS: APPENDIX D
U.S. EPA. Flame Retardant in Printed Circuit
Boards Partnership: Short Summary of
Elemental Analyses. DRAFT. December 9, 2009.
*This Short Summary is based on the work
presented in the following three documents,
which are also included in Appendix D:
ICL Industrial. JR 22 - Br and Cl Analysis in
Copper Clad Laminates - part II. February 12,
2009. (See page A-150)
ICL-IP Analysis of Laminate Boards. Memo
from Stephen Salmon. November 16, 2009.
(See page A-152)
Dow. Analysis of Chlorine and Bromine.
November 2, 2009. (See page A-156)
A-145
-------
Flame Retardant in Printed Circuit Board Partnership
Short Summary of Elemental Analyses
December 9, 2009
Dow and ICL-IP tested the seven laminate samples for elemental composition. Dow tested for
bromine and chlorine using neutron activation (NA). ICL-IP tested for aluminum, calcium,
magnesium, and phosphorus using ICP, bromine using titration, and chlorine using ion
chromatography. Results from Dow and ICL-IP are shown alongside prior XRF results.
Aluminum, Calcium, and Magnesium
The partnership had previously decided to analyze levels of aluminum, calcium, and magnesium
to determine whether any of these elements were present as a flame retardant filler, such as
A1(OH)3, Mg(OH)2 or CaCOs. As is shown in ICL's report, results for Al, Ca, and Mg were not
repeatable. In addition, results were low and further testing showed that Al, Ca, and Mg were
not completely digested in the initial procedure. This led ICL to conclude that the Al, Ca, and
Mg were most likely from glass fiber or glass treatment, and not from a flame retardant filler
(personal communication with ICL, Dec 2009). For these reasons, we do not summarize results
for Al, Ca, and Mg here, but instead focus on phosphorus, bromine, and chlorine.
Phosphorus
As is shown in Table 1 and Figure 1, phosphorus levels are highest in laminate 3. There is some
discrepancy between XRF and ICP results, but both test methods agree that laminate 3 has the
highest level of phosphorus.
Table 1. Phosphorus
Laminate
1
2
3
4
5
6
7
Test Method
ICP
wt%
0.011
0.012
1.7
1.1
0.80
0.69
0.52
±1
0.0068
0.0013
0.020
0.054
0.0065
0.0065
0
XRF
wt%
0.0016
0.0017
4.2
1.4
0.84
0.74
0.68
±1
0.00036
0.00054
0.10
n/a
n/a
n/a
0.0049
1 : Confidence intervals are based on variance among reported
values. It is not possible to determine the extent to which these
intervals account for measurement uncertainty.
n/a: not applicable (not enough data to determine confidence
bounds)
A-146
-------
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
Phosphorus
Laminate ID
Figure 1. Phosphorus levels measured by TCP and XRF
A-147
-------
Bromine
As is shown in Table 2 and Figure 2, bromine levels are highest in laminate 2. There is some
discrepancy in results for laminate 1 (titration results are an order of magnitude higher than
neutron activation results), but keep in mind that prior testing did not show noticeable levels of
brominated dioxins or furans for laminate 1. Laminates 3 through 7 appear to have negligible
amounts of bromine (two to three orders of magnitude lower than for laminate 2).
Table 2. Bromine
Laminate
1
2
3
4
5
6
7
Test Method
Titration
wt%
0.7
8.1
<0.04
<0.04
<0.04
<0.04
<0.04
±1
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Neutron Activation
wt%
0.0017
7.2
0.0038
0.00054
0.0026
0.00011
0.0014
±1
0.00093
0.30
0.000063
0.00012
0.0011
0.0000098
0.000079
XRF
wt%
n.d.
6.1
0.0047
n.d.
0.0012
n.d.
0.0012
±1
n/a
1.9
0.00015
n/a
n/a
n/a
0.00012
1 : Confidence intervals are based on variance among reported values. It is not possible to
determine the extent to which these intervals account for measurement uncertainty.
n/a: not applicable (not enough data to determine confidence bounds)
n.d.: not detected
Bromine
9n -,
8n -
7 n -
6n
.u
^o c n -
"S A n .
on.
2n
.u •
1 n -
On -
n
6
n
iii iii
1234567
Laminate ID
D Titration
• NA
DXRF
Figure 2. Bromine levels measured by titration, neutron activation (NA), and XRF
A-148
-------
Chlorine
Table 3 and Figure 3 show noticeably lower chlorine results with neutron activation and ion
chromatography than with XRF (order of magnitude difference), which is as expected under the
revised washing protocols. Despite potential discrepancies between test methods, the results
show that chlorine levels are similar between laminates, and along the order of 17100th to 1/10th
of a percent by weight.
Table 3. Chlorine
Laminate
1
2
3
4
5
6
7
Test Method
Ion Chromatography
wt%
0.06
0.02
0.02
<0.02
0.02
0.04
<0.02
±
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Neutron Activation
wt%
0.075
0.073
0.062
0.063
0.060
0.046
0.030
±1
0.0013
0.018
0.0013
0.00065
0.0023
0.0033
0.0020
XRF
wt%
0.88
0.59
0.52
0.45
0.43
0.49
1.0
±1
0.12
0.35
0.081
n/a
n/a
n/a
0.065
1 : Confidence intervals are based on variance among reported values. It is not possible to
determine the extent to which these intervals account for measurement uncertainty.
n/a: not applicable (not enough data to determine confidence bounds)
Chlorine
19-,
1 0 -
Oft -
S n R -
OA -
0 2 -
On
I*1 ]
FT
-L
J"
.U I I I I
12345
Laminate ID
|-i
1 "—^ 1 1
S,
,
:
6 7
• Ion
chromatography
• NA
DXRF
Figure 3. Chlorine levels measured by ion chromatography, neutron activation (NA), and XRF
Note: Ion chromatography results for laminate 4 and 7 were below detection limits, and are
shown in Figure 3 as one-half the detection limit.
A-149
-------
To:
From:
ICL industrial.
PRODUCTS
Pierre Georlette
Dr. Iris Ben David
BROMINE COMPOUNDS LTD.
P.O.Box 180 Beer-Sheva 84101 Israel
Tel:+972-8-6297001 Fax:+972-8-6297412
Iris Ben-David, Ph.D.
RD Division
www. icl-industrial .com
bendavidi@icl-ip.com
02/12/2009
Re: JR 2293 - Br and Cl Analysis in Copper Clad Laminates - part II
Following our previous report on the analysis of bromine and chlorine in Copper Clad
laminates (see Appendix-1) we received a request for analyzing the halides in these samples at
levels under 0.5 %. We analyzed the samples using ion chromatography, with detection limit of
0.02 % for chlorine and 0.04 % for bromine.
The results are summarized in the table.
Notes:
Sample ID
EPA-1
EPA-2
EPA-3
EPA-4
EPA-5
EPA-6
EPA-7
Br Content (%)
0.7 :
8.1 :
-------
Appendix-1: Our report from November 11, 2009 - JR 2283.
11/11/2009
To: Pierre Georlette
From: Dr. Iris Ben David
Re: JR 2283 - Br & Cl Analysis in Copper Clad Laminates
We received seven samples of Copper Clad laminates (marked EPA-1 to EPA-7). We analyzed the samples for
their bromine and chlorine contents. Two of the samples had metal strips on them; we examined only the metal free
section, in comparison with the other samples.
The Br/Cl contents are given below:
Notes:
2)
3)
4)
5)
Sample ID
EPA-1
EPA-2
EPA-3
EPA-4
EPA-5
EPA-6
EPA-7
Br Content
0.7% (iO.4%)1
8.1 %3(±0.2%)4
n.d.
n.d.
n.d.
n.d.
n.d.
Cl Content
n.d.2
n.d.
< 0.5 %4
< 0.5 %
< 0.5 %
< 0.5 %
< 0.5 %
The uncertainty at 1 % level is 5 %.
n.d. = Not detected.
Average of 5 specimens (including the second set of samples EPA 2).
The uncertainty at 10 % level is 2 %.
The analytical method used has a limit of quantification of 0.5 %. At levels under 0.5 % the uncertainty is >50%.
If the accuracy at lower levels of halides is important and should be determined, we can use a different analytical
method. Upon request, the analytical results will be available within a month.
With Best Regards,
2/2
JR 2293 - Br & Cl in copper clad laminates - part Il.doc
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Date: November 16, 2009
Subject: Analysis of Laminate Boards.
From: Stephen Salmon, ICL-IP
Determination of P, Al, Ca, Mg
Analyses were completed on seven laminate boards. The results show repeatability was
very good for P, but very poor for Al, Ca, and to a lesser extent Mg. The nature of the
sample matrix appears to be the problem. Details are given below.
The laminate boards were sampled by taking very thin slices across areas that did not
contain any of the copper cladding. The slivers were cross cut to produce very small
pieces. This material was mixed and sub-sampled for acid digestion to get a
representative sample across the board. It was noted that this cutting procedure produced
some very fine glass dust from the edges of the pieces. Some of this dust was included in
the sub-samples.
The samples were digested with sulfuric acid using nitric acid and 30% hydrogen
peroxide as needed to destroy the organic matrix. The resulting solution contained the
insoluble fiberglass. The digested samples were filtered through 0.45 um polypropylene
syringe filters into 100-mL volumetric flasks and made to volume at 4% sulfuric acid.
The samples prepared in triplicate were analyzed by inductively coupled plasma-optical
emission spectroscopy (ICP-OES) using calibration standards matched to the 4% sulfuric
acid of the samples.
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Results for triplicate analyses of the seven laminate boards are shown in Table 1.
Table 1
ICP Analysis of slivered laminate boards
Sample ID wt% Al wt% Ca wt % P wt% Mg
EPA-1 A 0.21 0.54 0.017 <0.01
EPA-1 B 0.26 0.62 <0.01 0.010
EPA-1 C 0.19 0.45 0.010 <0.01
EPA-2A 0.31 0.78 0.011 0.013
EPA-2B 0.32 0.79 0.011 0.013
EPA-2C 0.39 0.93 0.013 0.016
EPA-3A 0.21 0.50 1.71 <0.01
EPA-3B 0.40 0.32 1.71 <0.01
EPA-3C 0.48 0.78 1.74 <0.01
EPA-4A 0.35 0.68 1.14 0.080
EPA-4B 1.60 3.34 1.07 0.14
EPA-4C 0.27 0.74 1.16 0.070
EPA-5A 1.09 0.69 0.80 0.014
EPA-5B 2.34 0.51 0.81 0.013
EPA-5C 0.34 0.26 0.80 <0.01
EPA-6A 2.67 1.63 0.68 0.056
EPA-6B 2.96 1.37 0.69 0.046
EPA-6C 2.21 0.72 0.69 0.040
EPA-7A 2.86 1.74 0.52 0.085
EPA-7B 3.09 2.14 0.52 0.10
EPA-7C 1.81 0.96 0.52 0.059
The results show that only P determination was repeatable. To check if the fine glass
dust that was included at various levels in the acid digested samples skewed the results
four of the laminate boards were prepared again in triplicate. This time a single chip of
sample of the desired weight was cut out of three sections of the laminate board. The
acid digestion and ICP-OES analyses were repeated.
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The results of this evaluation are shown in Table 2.
Table 2
Repeat Digestions on single laminate board chips.
Sample ID wt% Al wt% Ca wt % P wt% Mg
EPA-4Achip 0.31 0.66 1.18 0.070
EPA-4Bchip 0.22 0.72 1.23 0.068
EPA-4Cchip 0.23 0.73 1.23 0.073
EPA-5Achip 0.38 0.25 0.81 0.004
EPA-5Bchip 0.80 0.67 0.83 0.010
EPA-5Cchip 0.85 0.57 0.83 0.011
EPA-6Achip 2.91 1.35 0.63 0.043
EPA-6Bchip 0.77 0.85 0.70 0.018
EPA-6Cchip 1.87 1.29 0.69 0.024
EPA-7Achip 0.49 0.24 0.50 0.017
EPA-7Bchip 0.39 0.34 0.51 0.016
EPA-7Cchip 0.43 0.35 0.51 0.012
The results show that P again was very repeatable and matched the values from digestion
of the small pieces. Al and Ca, and to a lesser extent Mg, again showed very poor
repeatability.
The acid digestion of the single chip samples resulted in four small sheets of fiberglass
from each sample. These were recovered from the filtration step and the washed
fiberglass was dried and weighed. The fiberglass was subjected to the acid digestion
procedure again and an ICP-OES analysis showed significant and variable amounts of Al
and Ca had not been recovered by the first digestion. Mg showed the same to a lesser
extent, but P was not detected indicating quantitative recovery in the original digestion.
Table 3 shows the results of this evaluation.
Table 3
Redigestion of fiberglass recovered from digestion of single chips.
Sample ID wt% Al wt% Ca wt % P wt% Mg
EPA-6 A chip 2nd 0.45 0.50 nd 0.016
EPA-6 B chip 2nd 0.64 1.30 nd 0.030
EPA 6 C chip 2nd 0.41 0.086 nd 0.011
The conclusion is that Al and Ca are in the fiberglass or can not be separated from the
sample matrix quantitatively. This is also the case for Mg, but to a lesser extent. P,
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however, is quantitatively recovered from the laminate board matrix by the procedure
used.
Determination of Br and Cl
An analysis of slivered laminate board for halogens was attempted by metallic sodium
reflux in isopropanol with silver nitrate titration for Br and Cl. Unfortunately, the
laminate board matrix proved to be impervious to extraction by the reagent and this
approach had to be abandoned.
Samples of the seven laminate boards were sent to ICL in Israel for sample preparation
by sodium peroxide bomb. Preliminary results are shown below. Other results are
pending and will be sent when available.
Date: 11/11/2009
To: Pierre Georlette
From: Dr. Iris Ben David
Re: JR 2283 - Br & Cl Analysis in Copper Clad Laminates
We received seven samples of Copper Clad laminates (marked EPA-1 to EPA-7). We
analyzed the samples for their bromine and chlorine contents. Two of the samples had
metal strips on them; we examined only the metal free section, in comparison with the
other samples.
The Br/Cl contents are given below:
Sample ID
EPA-1
EPA-2
EPA-3
EPA-4
EPA-5
EPA-6
EPA-7
Br Content
0.7% (iO.4%)1
8.1%3 (±0.2%)4
n.d.
n.d.
n.d.
n.d.
n.d.
Cl Content
n.d2
n.d.
< 0.5 %4
<0.5%
<0.5%
<0.5%
<0.5%
Notes:
1) The uncertainty at 1 % level is 5 %.
2) n.d. = Not detected.
3) Average of 5 specimens (including the second set of samples EPA 2)
4) The uncertainty at 10 % level is 2 %.
The analytical method used has a limit of quantification of 0.5 %. At levels under 0.5 %
the uncertainty is >50%. A different analytical method will be used to get more precise Cl
results. The analytical results will be available within two weeks.
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Triplicate samples were prepared by transferring 0.3 grams respectively into pre-cleaned
0.25-dram polyethylene vials. Samples were measured for thickness and cleaned with
isopropanol prior to placing into the vials. Areas with copper were not sampled.
Standards of chlorine, bromine were prepared from standard solutions and placed into
pre-cleaned 0.25 dram vials. The standards were diluted to the same volume as the
samples and the vials heat-sealed. The samples, standards and blanks were irradiated and
counted in four batches. Triplicate samples of EPA -2 were irradiated separately using
O.Olgrams. The higher concentration of bromine identified interferes with the detection
of chlorine. Thickness was measured in triplicate using a micrometer.
Sample ID
EPA1
EPA 3
EPA 4
EPA 5
EPA 6
EPA 7
20 min @ 250 kW
Cl (ppm)
td=lh
= lh
760±40
630±30
640±30
600±30
440±20
290±10
Br (ppm)
td=lh
tc=lh
15.5±0.8
38.2±1.9
4.5±0.2
20.6±1.0
1.0±0.1
13.3±0.7
10min@250kW
Cl (ppm)
td=lh
tc=lh
740±40
630±30
630±30
580±30
440±20
320±20
Br (ppm)
td=lh
tc=lh
9.7±0.5
37.8±1.9
5.2±0.3
37.8±1.9
1.1±0.1
14.7±0.7
10min@30kW
10 min decay
Cl (ppm)
td=lh
tc=lh
740±40
610±30
630±30
620±30
490±20
290±10
Br (ppm)
25.9±1.3
37.1±1.9
6.5±0.3
20.1±1.0
ND@2ppm
14.0±0.7
10 min@5kw: Cl td =10 min, tc = 7 min; Br td = 5 hour, tc = 1.5 hour
Sample ID
EPA 2
Cl (ppm)
650±130
Br (wt%)
6.9±0.3
Cl (ppm)
920±180
Br (wt%)
7.4 ±0.4
Cl (ppm)
630±130
Br (wt%)
7.3±0.4
Thickness
EPA1
EPA 2
EPA 3
EPA 4
EPA 5
EPA 6
EPA 7
Inch
0.018
0.016
0.019
0.018
0.018
0.017
0.018
Inch
0.021
0.018
0.019
0.017
0.018
0.017
0.018
Inch
0.019
0.018
0.02
0.02
0.018
0.017
0.018
Average± Stdev
0.019±0.002
0.018±0.001
0.020±0.001
0.019±0.001
0.018±0.001
0.017±0.001
0.018±0.001
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FLAME RETARDANTS IN PRINTED CIRCUIT
BOARDS: APPENDIX E
University of Dayton Research Institute. Use of
Cone Calorimeter to Identify Selected
Polyhalogenated Dibenzo-P-Dioxins/Furans and
Polyaromatic Hydrocarbon Emissions from the
Combustion of Circuit Board Laminates. October
22,2013.
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USE OF CONE CALORIMETER TO IDENTIFY SELECTED POLYHALOGENATED
DIBENZO-P-DIOXINS/FURANS AND POLY AROMATIC HYDROCARBON
EMISSIONS FROM THE COMBUSTION OF CIRCUIT BOARD LAMINATES
Final Report
Prepared for the U.S. Environmental Protection Agency
Sukh Sidhu, Alexander Morgan, Moshan Kahandawala, Kavya Muddasani
University of Dayton Research Institute
300 College Park, Dayton, OH 45469
Brian Gullett, Dennis Tabor
U.S. Environmental Protection Agency
Office of Research and Development
Research Triangle Park, NC 27711
October 22, 2013
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TABLE OF CONTENTS
1 Executive Summary 167
2 Introduction 169
2.1 Electronic Waste 169
2.2 Performance Requirements for Printed Circuit Boards 170
2.3 Project Goal 171
3 Experimental Methods 171
3.1 Laminate Preparation 173
3.2 Component Mixture Preparation and Component Mixture Grinding 175
3.3 Combustion Testing 176
3.3.1 Cone Calorimeter Apparatus Description 176
3.3.2 Cone Calorimeter Testing Methods 179
3.3.3 Sampling Train 179
3.3.4 Samples Tested 182
3.4 Sample Handling and Custody 183
3.4.1 Shipping Custody 183
3.4.2 Sample Identification and Log 183
3.5 By-product Extraction 183
3.5.1 Organic Compound Target List 184
3.5.2 EPA-RTP Experimental Strategy 184
3.5.3 Same-Sample Extraction of PCDD/Fs and PBDD/Fs 186
3.5.4 Cleanup and Fractionati on of PCDD/Fs and PBDD/Fs 186
3.6 Dioxin/Furan Analysis 187
3.6.1 HRGC/HRMS Calibration and Maintenance 187
3.6.2 HRGC/HRMS Analysis 187
3.6.3 Data Processing and Reporting 188
3.6.4 Quality Assurance/Quality Control 188
3.6.5 Pre-Sampling Spikes Quality Criteria and Performance 189
3.6.6 Pre-Extraction Spikes Quality Criteria 190
3.7 Polyaromatic Hydrocarbon Analysis 192
3.8 Organophosphorus and Chlorinated Benzene/Phenol Analysis 193
4 Results and Discussion 193
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4.1 Total Mass Burned 193
4.2 Smoke 194
4.3 CO/CO2 Emissions 196
4.4 Particulate Matter Emissions 198
4.5 PBDD/Fs and PCDD/Fs Emission Factors 199
4.6 PAH Emissions 202
4.7 Heat Release (Flammability) Results 209
5 Conclusions 212
6 Acknowledgments 213
7 Appendix A: Circuit Board Flammability Data 215
8 Appendix B: Experimental Conditions 234
9 Appendix C: Elemental Analyses of Component Mixtures 235
10 References 236
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LIST OF TABLES
Table 2-l.E-Waste by Category in 2010 170
Table 3-1. Overview of Phase II Testing Methodology 172
Table 3-2. Emission/Combustion Tests for Phase IIDfE Work 173
Table 3-3. Copper Area of Circuit Board Laminates 174
Table 3-4. Blend of Components to Mimic Circuit Board Components 176
Table 3-5 Laboratory ID Coding System 183
Table 3-6. PCDD/Fs and PBDD/Fs Target Analytes 184
Table 3-7. Composition of the PCDD/Fs Sample Spiking Solution 189
Table 3-8. Composition of the PBDD/Fs Sample Spiking Solution 189
Table 3-9. Pre-Sampling Spike Recovery Limits [%] 190
Table 3-10. Pre-Extraction Spike Recovery Limits [%] 191
Table 4-1. Total Mass Burned Per Sample 194
Table 4-2. Smoke Release Data 195
Table 4-3. CO/CO2 Emission Factors 197
Table 4-4. PM Emission Factors 198
Table 4-5. PBDD/Fs Emission Factors 201
Table 4-6. PAH Emission Factors from EPA List of 16* Priority PAHs for BFR and NFR at 50
and lOOkW/m2 206
Table 4-7. PAH Emission Factors from EPA List of 16* Priority PAHs for HFR and 1556 HFR
at 50 and lOOkW/m2 207
Table 4-8. Toxic Equivalent Emission Factors of Carcinogenic PAHs from EPA List of 16*
Priority PAHs 207
Table 4-9. Organophosphorous Compounds Detected 209
Table 4-10. Heat Release Summary for Laminates and Laminates + Component Powders Tested
at50kW/m2 211
Table 4-11. Heat Release Summary for Laminates and Laminates + Component Powders Tested
at lOOkW/m2 212
Table 7-1. Heat Release Rate Data (50 kW/m2) 216
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Table 7-2. Heat Release Data (100 kW/m2) 228
Table 8-1. Ambient Conditions during Cone Testing 234
Table 9-1. Elemental Analyses of Component Mixtures 235
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LIST OF FIGURES
Figure 3-1. Overview of Workflow for Combustion Testing and Analysis 172
Figure 3-2. NFR Sample 175
Figure 3-3. BFR Sample 175
Figure 3-4. HFR Sample 175
Figure 3-5. 1556-HFR Sample 175
Figure 3-6. Cone Calorimeter Schematic 177
Figure 3-7. Total Sampling Train Coupled with UDRI Cone Calorimeter 181
Figure 3-8. Schematic of Total Sampling Train 182
Figure 3-9. Original RTF Experimental Strategy 185
Figure 4-1. Smoke Release Plot 196
Figure 4-2. CO/CO2 Emission Factors Plot 198
Figure 4-3. Particular Matter (PM) Emission Factors 199
Figure 4-4. PBDD/Fs Emission Factors Plot for ND=0 and EMPC=EMPC 202
Figure 4-5. PAH Emission Factors Plotted for Naphthalene and Higher Molecular Weight PAHs
Detected from the EPA List of 16* Priority PAHs 203
Figure 4-6. PAH Emission Factors for Fluorene and Higher Molecular Weight PAHs Detected
from the EPA List of 16* Priority PAHs 204
Figure 4-7. Emission Factors of Carcinogenic PAHs from the EPA List of 16* Priority PAHs 205
Figure 4-8. Toxic Equivalent Emission Factors of Carcinogenic PAHs from EPA List of 16*
Priority PAHs Compared at 50 kW/m2 Conditions 206
Figure 7-l.HRR for BFR Sample 218
Figure 7-2. Final Chars for BFR Sample 218
Figure 7-3. HRR for BFR+ P Sample 219
Figure 7-4. Final Chars for BFR + P Sample 219
Figure 7-5. HRR for BFR+ PHF Sample 220
Figure 7-6. Final Chars for BFR + PHF Sample 220
Figure 7-7. HRR for NFR Sample 221
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Figure 7-8. Final Chars forNFR Sample 221
Figure 7-9. HRR for HFR Sample 222
Figure 7-10. Final Chars for HFR Sample 222
Figure 7-11. HRR for HFR+ P Sample 223
Figure 7-12. Final Chars for HFR + P Sample 223
Figure 7-13. HRR for HFR+ PHF Sample 224
Figure 7-14. Final Chars for HFR+ PHF Sample 224
Figure 7-15. HRR for 1556 HFR Sample 225
Figure 7-16. Final Chars for 1556 HFR Sample 225
Figure 7-17. HRR for 1556 HFR + P Sample 226
Figure 7-18. Final Charfor 1556 HFR + P Sample 226
Figure 7-19. HRR for 1556 HFR + PHF Sample 227
Figure 7-20. Final Chars for 1556 HFR + PHF Sample 227
Figure 7-21. HRR for BFR Sample 229
Figure 7-22. Final Chars for BFR Sample 229
Figure 7-23. HRR forNFR Sample 230
Figure 7-24. Final Chars forNFR Sample 230
Figure 7-25. HRR for HFR Sample 231
Figure 7-26. Final Chars for HFR Sample 231
Figure 7-27. Heat Release Rate Plot 232
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LIST OF ACRONYMS
1556 HFR 1556 halogen-free flame retardant
ASTM American Society for Testing and Materials
Avg HRR Average heat release rate
BFR Brominated flame retardant
CIL Cambridge Isotope Laboratories
CO/CO2 Carbon monoxide/carbon dioxide
DfE Design for the Environment Program
DQI Data quantity indicator
DQO Data quantity objective
EMPC Estimated maximum possible concentration
EMT Environmental Monitoring Technologies Inc
EPA U.S. Environmental Protection Agency
E-waste Electronic waste
FIGRA Fire growth rate
FMS Fluid Management Systems Inc
FTT Fire testing technology
GC/MS Gas chromatography/mass spectrometry
HFR Halogen-free flame retardant
HRGC High resolution gas chromatography
HRMS High resolution mass spectrometry
HRR Heat release rate
ISO International Organization for Standardization
KOH Potassium hydroxide
LRMS Low resolution mass spectrometry
MARHE Maximum average rate of heat emission
NFR No flame retardant
NGO Non-governmental organization
NRMRL National Risk Management Research Laboratory
OSL EPA Organic Support Laboratory
P Populated by halogen components
PAHs Polyaromatic hydrocarbons
PBDD/Fs Polybrominated dibenzo-p-dioxins/furans
PCB Printed circuit board
PCDD/Fs Polychlorinated dibenzo-p-dioxins/furans
Peak HRR Peak heat release rate
PFK Perfluorokerosene
PHF Populated by low-halogen components
PM Particulate matter
PUF Polyurethane foam
R&D Research and development
RoHS Restriction of Hazardous Substances
RTF EPA Research Triangle Park
TBBPA Tetrabromobisphenol A
TEF Toxic equivalent factor
TEQ Toxic equivalent quantity
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THR Total heat release
Tig Time to ignition
UDRI University of Dayton Research Institute
UL Underwriters Laboratories
UV Ultraviolet
WEEE Waste Electrical and Electronic Equipment
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1 Executive Summary
The U.S. Environmental Protection Agency (EPA) Design for the Environment (DfE) program
convened a partnership to conduct an alternatives assessment for TBBPA in printed circuit
boards. The partnership determined that combustion testing of sample laminates using the
alternatives would strengthen the assessment and industry decision-making on use of
alternatives. This report explains the outcome of that testing.
The purpose of this study was to understand the potential emissions of halogenated dioxins or
furans and polyaromatic hydrocarbons (PAHs) from burning circuit board laminates. The
methods of this study mimic two types of fire events: open burn and incineration of electronic
waste (e-waste), both of which are used for precious metal recovery. While difficult to model
these two complex fire scenarios exactly, the University of Dayton Research Institute (UDRI)
utilized a cone calorimeter, a fire safety engineering instrument capable of simulating these
scenarios and measuring combustion efficiency.
Combustion conditions, as well as model samples for burning, were selected with input from a
group of stakeholders "Partnership" assembled by DfE. These stakeholders included circuit
board laminate manufacturers, flame retardant producers, government regulators, and non-
governmental organizations (NGOs) with vested interests in the potential emissions from these
burning items. Some stakeholders funded the UDRI experiments while EPA funded the sample
extractions and dioxin/furan analyses.
The results of this study show that when these materials are burned, even at high heat flux that
would attempt to mimic an incinerator, various pollutants are released. Further, flame retarded
materials release more PAHs and other pollutants when burning compared to materials that are
not flame retarded, but this is expected and indicates that the flame retardants are working as
designed. Specifically, the retardation of flame and combustion will result in more incomplete
combustion products.
The combined dioxin/furan and PAH emission studies suggest that circuit board polymers cannot
be analyzed in isolation when determining emissions; the entire populated board must be
considered. While certain pollutants were found in both flame retardant and non-flame retardant
circuit boards, toxicity studies were not conducted. Therefore the relative toxicity of the
combustion by-products from the different laminate formulations can only be partially
calculated.
While the exact flame retardants used in this study were not identified to the Partnership, the
flame retardant chemistry of these materials behaved as expected. Brominated flame retardants
inhibited combustion and produced brominated phenols (detected, but not quantified), dioxins,
furans, and other aromatics during burning. Non-halogenated flame retardants (presumed to be
phosphorus-based) slowed down burning through char formation. This generated more PAHs
than the non-flame retardant circuit boards in certain circumstances (lower heat flux) but less
PAHs when compared to BFRs.
In general, these emissions fit the known combustion chemistry of these flame retardants classes.
Therefore, this study contributes data supporting the approach that, to achieve both fire safety
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and lower emissions, disposal must be done properly with full incineration and appropriate air
pollution control devices in place.
Despite this confirmation of open burning pollution, the study does also leave some questions
unanswered. The results from this study are not definitive regarding which specific pollutants
were released since chemical identification was limited. Further, the results do not show which
chemistries and circuit board components may lead to lower emissions, even under simulated
incineration conditions. A cone calorimeter may not achieve temperatures as high as those of
real-world incinerators. The high heat flux results may not be fully indicative of real-world
emissions should printed circuit boards be put into an incinerator. Because some flame retardants
(including those in this report) inhibit combustion even at very high heat fluxes, additional
research is needed to identify circuit board flame retardant chemistry with lower environmental
and human health impact emissions. Incinerator conditions are likely to reduce the emissions, but
additional emission controls (baghouses, filters) may be needed to prevent all emissions of
concerns as the efficiency of an incinerator is a function of its design and actual operation
temperatures.
Finally, this study demonstrated that the technique of using the cone calorimeter (ASTM E1354)
for emission studies in combination with a custom-built emissions capture sampling train was
successful with small samples. Specifically, the cone calorimeter can be used to collect
emissions from circuit board materials without having to conduct actual open burns. However
this proved to be a labor intensive analytical technique needing refinement of procedures. To
summarize the findings of this study:
50kW/m2heatflux:
• BFR: PBDD/Fs emitted. PAHs emitted at higher levels compared to other samples.
• FIFR: PAHs emitted at higher levels than NFR sample.
• NFR: PAHs emitted at lowest levels compared to other samples.
100 kW/m2 heat flux:
• BFR: PBDD/Fs emitted. PAHs emitted at higher levels compared to other samples.
• HFR: PAHs emitted at lowest levels compared to other samples.
• NFR: PAHs emitted at a level slightly lower than the BFR sample.
Effect of components on emissions:
• PBDD/Fs: PBDD/Fs were similar or lower than sample without components.
• PAHs: In general, presence of components reduced PAH emissions for BFR, were similar or
slightly higher for HFR and were lower for 1556 HFR. The size of these differences varied
depending on how PAHs were defined (see section 4.6).
Smoke, PM, CO and CO2 release:
• Smoke release was higher for BFR than HFR laminates. Smoke release was higher with
components due to greater amount of material. PM generally had small differences between
samples. There were negligible differences in CO release between samples. CO2 release was
lowest for BFR but with small differences between samples. Results are complex and
smoke/PM results do not always correlate.
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2 Introduction
2.1 Electronic Waste
According to statistics gathered by the Electronics TakeBack Coalition, which were derived from
EPA statistics, 2.4 million tons of e-waste were generated in 2010, only 27% of which was
recycled (see Table 2-1).l However, with the price of precious metals and rare earths increasing
due to demand and geopolitical issues, there is increased demand to recycle electronics in order
to recover the metals and rare earths. One of the more popular and cost-effective techniques for
this type of metal/rare earth recovery is incineration, which burns off the polymeric components
of the e-waste and leaves behind inorganic ash. This ash can be further smelted down and refined
to isolate the precious metals and rare earths. When incineration is not conducted properly, the
combustion of polymeric components creates toxic by-products that can be released into the
environment. Improper incineration of electronics in developing countries, as seen in popular
magazines like National Geographic2, has led to concerns about the improper disposal of these
products and has influenced the research in this report. Improper disposal of waste that leads to
widespread environmental damage and under-ventilated toxic by-product release is highly
undesirable and illegal in many countries. This issue may be attributable to companies sending e-
waste to countries with looser regulations for improper incineration instead of following
incineration regulatory standards in place in many developed countries. The drivers for improper
waste disposal are numerous, but ultimately financial, and the drive to recover precious metals is
causing more developed countries to keep the wastes inside borders to recycle materials via
internal infrastructure. However, even for operations that will utilize clean burning incinerators
and afterburner/scrubber technology, there still needs to be some knowledge of what is being
released from burning this waste so incinerators can be designed and engineered correctly.
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Table 2-1. E-Waste by Category in 2010
E-Waste by Ton in 2010
Products
Computers
Monitors
Hard copy devices
Keyboards and Mice
Televisions
Mobile devices
TV peripherals*
Total (tons)
Total disposed** (tons)
423,000
595,000
290,000
67,800
1,040
19,500
Not included
2,440,000
Trashed (tons)
255,000
401,000
193,000
61,400
864,000
17,200
Not included
1,790,000
Recycled (tons)
168,000
194,000
97,000
6,460
181,000
2,240
Not included
649,000
Recycling Rate (%)
40%
33%
33%
10%
17%
11%
Not included
27%
E-Waste by Unit in 2010
Products
Computers
Monitors
Hard copy devices
Keyboards and Mice
Televisions
Mobile devices
TV peripherals*
Total (units)
Total disposed** (units)
51,900,000
35,800,000
33,600,000
82,200,000
28,500,000
152,000,000
Not included
384,000,000
Trashed (units)
31,300,000
24,100,000
22,400,000
74,400,000
23,600,000
135,000,000
Not included
310,000,000
Recycled (units)
20,600,000
11,700,000
11,200,000
7,830,000
4,940,000
17,400,000
Not included
73,700,000
Recycling Rate (%)
40%
33%
33%
10%
17%
11%
Not included
19%
Computer products include CPUs, desktops, and portables.
Hard copy devices are printers, digital copiers, multi-functions and faxes.
Mobile devices are cell phones, personal digital assistants (PDAs), smartphones, and pagers.
*Study did not include a large category or e-waste: TV peripherals, such as VCRs, DVD players, DVRs, cable/satellite receivers, converter boxes,
game consoles.
**"Disposed" means going into trash or recycling. There totals don't include products that are no longer used, but which are still stored in homes
and offices.
1 Table adapted from "Facts and Figure on E-Waste and Recycling", Electronics TakeBack Coalition, 2012. Statistics from "Electronics Waste
Management in the United States Through 2009", U.S. EPA, 2011.
2.2 Performance Requirements for Printed Circuit Boards
The materials in printed circuit boards are influenced by performance and regulatory
requirements that must be met by manufacturers. These selections ultimately influence the
emissions from these components when they burn. For electronic products produced today,
numerous environmental requirements must be met. Environmental regulations in the European
Union, namely the Restriction of Hazardous Substances (RoHS)3 and Waste Electrical and
Electronic Equipment (WEEE)4 directives have been driving the elimination of specific metals
and organic compounds of environmental concern so that incineration and recycling are easier,
and in the event of improper disposal, environmental damage is limited. Regulations from one
nation automatically affect other nations as most electronics manufacturers prefer to produce for
a global market rather than tailor specific products for specific markets that would result in
higher manufacturing and research and development (R&D) costs.
Flame retardants are added to consumer products, including printed circuit boards, to protect
highly flammable polymers against potential fire/ignition risks. The primary fire risk that flame
retardants are protecting against in circuit boards is that of an electrical fault or short circuit
ignition source that can cause the polymer (typically an epoxy) to thermally decompose and
ignite. This ignition site can lead to flame spread across the board and can cause the electronic
casing (also typically made out of flammable polymer) to also ignite, which may lead to flame
spread out of the electronic device into a larger compartment such as a home, a vehicle, or a
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mass transport structure (e.g., subway, train, bus), which may contain other flammable products
that can cause the initial fire to further propagate. If a fire gets out of control, one might
hypothesize that because flame retardants may prevent a product from being fully consumed in
an accidental fire event, there is less total emissions when compared to a non-flame retardant
product that fully ignites. This is especially true if the non-flame retardant product is composed
of a high heat release material which in turn causes other nearby objects to burn and lead to a
large fire event (flashover). It should be pointed out though that this toxic emission reduction
enabled by flame retardant products in the event of accidental fires is only realized in life cycle
models if that product is disposed of properly at the end of its lifetime.5'6' If products are not
disposed of properly then flame retardants have some potential to leach into the environment and
lead to measureable levels of pollution. The flame retardant technology in use today for most
circuit boards typically consists of brominated bisphenol A epoxies that are co-polymerized into
the circuit board, or are reactive phosphorus-based flame retardants that are also co-polymerized
into the circuit board.8'9'10 These technologies have been in use for decades because they are cost-
effective and reliable while not compromising other essential epoxy circuit board properties
(e.g., electrical insulation properties, mechanical). These systems in place today served as the
baseline for the DfE project initially conducted in 2008-09 to study the emissions of circuit
boards using brominated and phosphorus-based flame retardants.11
2.3 Project Goal
The goal of this project was to understand the potential emissions of halogenated dioxins,
halogenated furans, and PAHs and fire characteristics of a standard tetrabromobisphenol A
(TBBPA) laminate compared to different halogen-free laminates in various scenarios with and
without typical circuit board components. The methods of this study mimic two types of fire
events used for precious metal recovery: open burning and proper incineration. Definitions of
open burning and proper incineration are needed here:
• Open burning means that combustion is done in a crude vessel, open to the environment,
where there are no good engineering measures in place to capture emissions or drive the
combustion process to completion.
• Proper incineration means that combustion is carried out in a system designed and
engineered to fully combust a material can capture its emissions through the use of
afterburner and baghouse-type emissions capture systems.
The results will provide scientific information to aid electronics and electrical manufacturers in
their decision-making processes to design and choose sustainable and environmentally-friendly
materials for their products.
3 Experimental Methods
A series of circuit boards were selected based on Phase I of this project to be tested under various
conditions mimicking open burning and incineration operations. The components used on circuit
boards were ground up and combusted along with the copper-clad circuit board laminate to
simulate the potential emissions from printed circuit board e-waste. An overview of the testing
methodology for Phase II of this project is provided in Table 3-1.
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Table 3-1. Overview of Phase II Testing Methodology
Laminates Burned (Acronym)
Components Burned
Laminate/Component
Combinations Burned
Scenarios (Heat Flux)
Analytes Tested
TBBPA laminate (BFR)
Non-flame retardant laminate (NFR)
Halogen-free flame retardant laminate (HFR)
Halogen-free flame retardant laminate (1556-HFR)
Standard halogen components (P)
Low-halogen components (PHF)
BFR + standard halogen components (BFR +P)
BFR + low-halogen components (BFR + PHF)
HFR + standard halogen components (HFR + P)
HFR + low-halogen components (HFR + PHF)
1556-HFR + standard halogen components (1556HFR + P)
1556-HFR + low-halogen components (1556HFR + PHF)
Open Burn (50 kW/m2) (Laminate Name -50)
Incineration (100 kW/m2) (Laminate Name - 100)
Polybrominated dibenzo-p-dioxins/furans (PBDD/Fs)
Polyaromatic hydrocarbons (PAHs)
Multiple entities were responsible for conducting different parts of Phase II's combustion testing
experiment. Figure 3-1 depicts the workflow throughout the project. DfE facilitated and oversaw
the workflow by communicating directly with Isola, Seagate, UDRI, and EPA Research Triangle
Park (RTF).
Isola
Laminate
preparation
Seagate
Component mixture
preparation
EMT
Component mixture
grinding
UDRI
Combustion
testing
RTF
Byproduct
extraction
Dioxin/furan
analysis
UDRI
Phosphorus and
PAH analysis
Figure 3-1. Overview of Workflow for Combustion Testing and Analysis
The circuit board laminates selected and the conditions used to burn the components and circuit
board combinations are shown in Table 3-2. This experimental plan was created with input from
the DfE stakeholders participating in this project including government officials, NGOs, circuit
board laminate manufacturers, electronics producers, and flame retardant producers. The
instrument and method selected to mimic open burning and incineration was the cone
calorimeter, which is a standard fire science measurement tool (ASTM El354, ISO 5660) used to
quantify heat release, smoke release, and CO/CO2 emissions from burning objects in a variety of
fire scenarios. This tool was chosen based on UDRI hypothesis that it could mimic burning
conditions of interest to the program while providing quantitative emissions on complex
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heterogeneous circuit board samples. More specifically, the cone calorimeter provided a dynamic
model in that it could burn a realistic amount of material (an actual circuit board laminate with
components or component mimics) and be instrumented in such a way to capture all of the
emissions from that burning event.
UDRI and EPA conducted the experiments in Table 3-2 in 2011. The original experiment plan
included a third combustion scenario for low-oxygen combustion. These low-oxygen
experiments were not carried out because the low-oxygen attachment for the cone calorimeter
was unable to yield dependable results for simulated smelting conditions at 100 kW/m heat flux
at 10% 02. The investigators discovered that when a sample was initially pyrolyzed/burned
under these conditions, combustion gases escaped from the top of the unit where they could
potentially be exposed to more oxygen. This event could lead to a more complete combustion
and thus generate inaccurate results. For reasons of integrity and efficiency, UDRI and the
partnership collectively decided to exclude the 100 kW/m2 heat flux at 10% 02 test condition
from the study.
Table 3-2. Emission/Combustion Tests for Phase II DfE Work
Heat
flux
50
kW/m2
100
kW/m2
Combustion
atmosphere
Air
(Open-burn)
Air
(Incineration)
Sample
description
BFR
BFR + P
BFR + PHF
HFR
HFR + P
HFR + PHF
1556 HFR
1556 HFR + P
1556 HFR +
PHF
NFR
NFR
BFR
HFR
Subtotal
Total (blanks + laminates)
#of
blank
runs1
2
2
2
1
1
1
1
1
1
1
1
1
1
16
#of
laminate
burns
2
2
2
2
2
2
2
2
2
2
2
2
2
26
42
PBDD/Fs
X
X
X
Test
Blanks
for
PBDD/Fs
X
X
X
X
X
X
PAHs
X
X
X
X
X
X
X
X
X
X
X
X
X
Phosphorus
X
X
X
X
X
X
X
X
X
X
X
X
X
Blanks between burns of the same laminate for the first several burns that could produce PBDD/Fs were analyzed
for PBDD/Fs carry-over. The blanks were clean; therefore the number of blanks in subsequent sets of samples was
reduced.
3.1 Laminate Preparation
The laminate manufacturer Isola was responsible for laminate preparation. Each laminate was
61cm x 46cm (2,806cm2) and had a 4-ply 2116 Taiwan glass S409 finish. These samples were
prepared by pressing each side of the laminates with loz of shiny copper from Nan Ya and
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etching a portion of the copper from the laminate using standard methods and procedures, just as
was done during Phase I testing (see Phase 1 Report)12, followed by a rinse with dilute KOH. To
prepare the copper clad laminates for etching, a portion of the copper was masked with an acrylic
tape and the rest of the copper was left exposed. Standard cupric chloride solution (2.5% normal,
266°C) was then applied to the laminate using a chemical etching machine. Etched laminates
were then washed with KOH (2.5% normal) to remove residual chlorine. During preliminary
testing, laminates were washed only with water and not with KOH. However, it is standard
practice in industry to wash laminates with dilute KOH after etching, so the partnership decided
to replicate this approach to reflect real-world conditions.
Due to a miscommunication, Isola initially etched off 25% of the copper, leaving 75% of the
surface area covered by copper. However, the partnership agreed that a copper surface area of
approximately 33% would be more representative of real-world conditions. The copper was
distributed evenly over the surface in a way that allowed UDRI to cut the laminate into 100mm x
100mm squares for combustion testing, each containing an equal amount of copper. In order to
achieve a surface area as close as possible to 33% and also obtain an even distribution of copper,
Isola etched the copper so that 25% remained on one side, and 37.5% on the other side. This
resulted in total surface area coverage of 31%. The total amount of copper present in the actual
samples is shown in Table 3-3. Pictures of representative samples of the four different copper
clad sample types are provided in Figure 3-2 through Figure 3-5.
Table 3-3. Copper Area of Circuit Board Laminates
Sample Description-Heat Flux (kW/m2)
BFR - 50
BFR - 50
BFR - 100
BFR - 100
BFR + P - 50
BFR + P - 50
BFR + PHF - 50
BFR + PHF-50
HFR - 50
HFR - 50
HFR - 100
HFR - 100
HFR + P - 50
HFR + P - 50
HFR + PHF - 50
HFR + PHF - 50
1556 HFR - 50
1556 HFR - 50
1556HFR + P-50
1556HFR + P-50
1556 HFR + PHF -50
1556 HFR + PHF -50
NFR-50
Copper area content (%)
32.01
32.56
32.95
32.85
33.86
33.50
32.85
32.76
32.66
32.78
32.72
32.68
32.98
32.65
32.96
31.90
32.92
32.86
33.12
33.10
32.87
32.68
32.75
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Sample Description-Heat Flux (kW/m2)
NFR-50
NFR - 100
NFR - 100
Copper area content (%)
32.80
32.22
32.25
Figure 3-2. NFR Sample
Figure 3-3. BFR Sample
Figure 3-4. HFR Sample
Figure 3-5.1556-HFR Sample
3.2 Component Mixture Preparation and Component Mixture Grinding
Seagate prepared a standard mixture of components, which Environmental Monitoring
Technologies, Inc. (EMT) ground up and sent to UDRI for combustion testing. The mixture was
combusted with selected laminate samples to simulate populated circuit boards. Both a low-
halogen mixture and a standard halogen mixture were prepared and were added to the laminates.
To the extent possible, the types of components in the low-halogen and standard halogen
mixtures were made identical. Seagate formulated and supplied the mixtures based on the
electronic components found on standard disk drive boards. Seagate provided as much detail as
possible about the composition of the ground-up mixtures and calculated the amount to add to
each laminate sample. The mixtures included integrated circuits, resistors, capacitors, connectors
(main source of plastic housing), shock sensors, and accelerometers. The partnership decided to
grind up components into a mixture prior to combustion testing. The blend of components that
was ground up to mimic circuit board components is shown in Table 3-4. Since the chemical
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composition of the component mixtures will determine emissions, Seagate provided information
on the chemicals present in the component mixtures, which is shown in Appendix C: Elemental
Analyses of Component Mixtures.
There are a few advantages to using ground-up components instead of whole components:
• More reliable results: Combustion results are consistent for ground-up components, but
are not consistent for whole components. This is because small changes in the placement
of whole components on the boards can affect the amount and type of materials that come
into contact with each other during combustion, which affects the formation of
combustion by-products.
• Better estimate of worst-case-scenario: Using ground-up components ensures maximum
contact between component materials and would give a higher probability of producing
combustion by-products.
• More inclusive sample: Capacitors can be included in the mixture of ground-up
components, as they are not an explosion hazard when ground-up.
• Less variability in sample preparation: Components do not have to be attached to the
laminate, which removes potential sources of variability (e.g., human error that might
occur while fixing components to the laminate and increased probability of introducing
contaminants).
Table 3-4. Blend of Components to Mimic Circuit Board Components
Component
Resistor (fixed)
Capacitor
Shock Sensor
Xstr (thermistor, bipolar transistor, FET)
Frequency Drive
EMIRFI Filter
Inductor
Integrated Circuit (custom drive specific, linear, memory)
Connector
Total
Amount (g)
Typical PCB1
0.07
1.59
0.03
0.08
0.06
0.02
0.53
1.64
3.05
7.05
Component Mix
30.77
694.51
10.94
33.19
25.38
6.57
229.82
718.82
1335.17
3085.17
Typical circuit board component mass/surface area of board is 0.128 g/cm . The component mixture
loading used for experiments was 0.1 g/cm2 (10±0.05 g/100 cm2 of laminate burned).
3.3 Combustion Testing
3.3.1 Cone Calorimeter Apparatus Description
A cone calorimeter (FTT, United Kingdom) housed at UDRI was modified and used to
characterize emissions from combustion of various printed circuit board laminate samples. The
cone calorimeter is a fire testing instrument which quantitatively measures the inherent
flammability of material through the use of oxygen consumption calorimetry, and is a standard
technique14 under ASTM E-1354/ISO 5660. This instrument was designed primarily as a fire
safety engineering tool, but has found great utility as a scientific tool for understanding fire
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performance in relation to regulatory pass/fail tests as will be referred to in the next paragraph. In
effect, it mimics a well-ventilated forced combustion scenario of an object being exposed to a
constant heat source and constant ventilation (Figure 3-6). This scenario represents many real
world fires where an object or material is aflame and radiates heat to other objects that also catch
fire as a result. The cone calorimeter serves as a very useful fire safety engineering tool by
looking at the heat release rates of a material under these forced conditions.
By studying the various parameters measured by the cone calorimeter, one can correlate the cone
calorimeter measurements to other tests, or, bring understanding of how a material behaves when
a flame is exposed to various fire scenarios. Work on comparing cone calorimeter to other tests
has included full scale flammability tests,15 bench scale tests like UL-94 or limiting oxygen
16-20
21
22
index, " automotive material flame spread tests, wire and cable flame spread tests, and other
types of fire tests/scenarios
Figure 3-6.
23-26
A schematic of the cone calorimeter basic setup is shown in
Loser photometer beom
including temperature measurement
Temperature end differential
pressure measurements taken here
Soot sample tube
Exhaust
blower
Soot collection filter
Schciust
hood
Cone heater
1——-Spark igniter
Specimen
load OEII
Vertical orientation
Figure 3-6. Cone Calorimeter Schematic
Several measurements can be obtained from the cone calorimeter. The cone calorimeter at UDRI
is equipped with a laser for smoke measurements (laser photometer beam in Figure 3-6), oxygen
sensor (paramagnetic) for measuring oxygen consumption, and load cell for measuring mass loss
as the sample pyrolyzes during heat exposure. The instrument at UDRI also has a CO/CO2
(infrared-based) detection system, allowing for the measurement of CO/CO2 production as a
function of time during sample combustion. From these parts of the instrument, various
measurements are collected during each test which can reveal scientific information about
material flammability performance. These include:
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Time to ignition (Tig): Measured in seconds, this is the time to sustained ignition of the
sample. Interpretation of this measurement assumes that earlier times to ignition mean that
the sample is easier to ignite under a particular heat flux.
r\
Heat Release Rate (HRR): The rate of heat release, in units of kW/m , as measured by
oxygen consumption calorimetry.
Peak Heat Release Rate (Peak HRR): The maximum value of the heat release rate during the
combustion of the sample. The higher the peak HRR, the more likely that flame will self-
propagate on the sample in the absence of an external flame or ignition source. Also, the
higher the peak HRR, the more likely that the burning object can cause nearby objects to
ignite.
Time to Peak HRR: The time to maximum heat release rate. This value roughly correlates
the time it takes for a material to reach its peak heat output, which would in turn sustain
flame propagation or lead to additional flame spread. Delays in time to peak HRR are
inferred to mean that flame spread will be slower in that particular sample, and earlier time to
peak HRR is inferred to mean that the flame spread will be rapid across the sample surface
once it has ignited.
Time to Peak HRR - Time to Ignition (Time to Peak HRR - Tig): This is the time in
seconds that it takes for the peak HRR to occur after ignition rather than at the start of the test
(the previous measurement). This can be meaningful in understanding how fast the sample
reaches its maximum energy release after ignition, which can suggest how fast the fire grows
if the sample itself catches fire.
Average Heat Release Rate (Avg HRR): The average value of heat release rate over the
entire heat release rate curve for the material during combustion of the sample.
Starting Mass, Total Mass Lost, Weight % Lost: These measurements are taken from the
load cell of the cone calorimeter at the beginning and end of the experiment to see how much
total material from the sample was pyrolyzed/burned away during the experiment.
r\
Total Heat Release (THR): This is measured in units of MJ/m and is the area under the heat
release rate curve, from time to ignition to time to flameout, representing the total heat
released from the sample during burning. The higher the THR, the higher the energy content
of the tested sample. THR can be correlated roughly to the fuel load of a material in a fire,
and is often affected by polymer chemical structure.
Total Smoke Release: This is the total amount of smoke generated by the sample during
burning in the cone calorimeter from time to ignition to time to flameout. The higher the
value, the more smoke generated either due to incomplete combustion of the sample, or due
to polymer chemical structure. Note that this is a light obscuration measurement, and the
smoke measurement does not discriminate between particulate matter (PM) which obscures
light and organic vapors/pyrolyzed molecules which also may obscure light.
Maximum Average Rate of Heat Emission (MARHE): This is a fire safety engineering
parameter,27 and is the maximum value of the average rate of heat emission, which is defined
as the cumulative heat release (THR) from time t=0 to t divided by time t. The MARHE can
best be thought of as an ignition modified rate of heat emission parameter, which can be
useful to rank materials in terms of ability to support flame spread to other objects.
Fire Growth Rate (FIGRA): This is another fire safety engineering parameter, determined by
dividing the peak HRR by the time to peak HRR, giving units of kW/m per second. The
FIGRA represents the rate of fire growth for a material once exposed to heat, and higher
FIGRA suggest faster flame spread and possible ignition of nearby objects.
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• CO/CO2 Yields: This is the total measured amounts of CO/CO2 measured during testing,
pre-ignition and post-ignition. The yields are in units of kg gas (CO, CC^) per kg sample.
3.3.2 Cone Calorimeter Testing Methods
Circuit board samples were provided as very thin (0.4mm to 0.6mm thick) epoxy + e-glass
laminates. These laminates contained copper plating in squares on both sides of the laminates
and were cut in such a way that each sample had the same amount of copper metal present in the
same configuration. Since the laminates provided were too large to be tested as is in the cone
calorimeter, the samples were cut into 100 cm2 square (±0.1 cm2) pieces for cone calorimeter
testing. Samples were not conditioned in any way prior to testing. All of the samples were tested
as single ply laminates, with some of the laminates also having ground component powder put
upon them in lOg batches prior to testing in the cone. Any powder used was weighed out right
before the cone experiment and spread evenly across the sample surface. The powder was not
conditioned before use but was always kept in a sealed jar and was weighed out with a typical
benchtop digital scale (accurate to +/- lOmg).
Samples tested included epoxy with brominated flame retardant (BFR), epoxy with non-flame
retardant (NFR), and two epoxies each with different halogen-free flame retardant additives
(HFR). Powders put on the board samples include standard halogen-containing component
powder (P) and low halogen-containing component powder (PHF).
Cone calorimeter experiments were conducted on a FTT Dual Cone Calorimeter as per the
ASTM E-1354-07 method at two heat fluxes (50 kW/m2 and 100 kW/m2). Samples were tested
in triplicate without frame and grid, with the back side of each sample wrapped in aluminum foil.
The only deviation from the ASTM method was that an exhaust flow of 15 L/s was used instead
of the standard 24 L/s exhaust flow rate. The lower flow rate was used to better mimic the "open
burning" fire scenario as the normal 24 L/s flow rate would give more oxygen to the fire than is
typically seen in a "open burning" flaming combustion scenario. Heat release rate data from cone
calorimeter can be found in Appendix A: Circuit Board Flammability Data.
3.3.3 Sampling Train
The total sampling train was designed and constructed specifically for these experiments to
collect the total exhaust gas emitted from the combustion of samples in a standard cone
calorimeter (Figure 3-7 and Figure 3-8). Sampling the total exhaust reduces the amount of
sample that has to be burned to characterize and quantify emissions. The exhaust duct on the
FTT Dual Cone Calorimeter from Fire Testing Technology Limited, UK, was modified to enable
connecting of the total sampling train. The exhaust hood above the combustion zone was
connected to the sampling exhaust duct (110mm in diameter) with a cooling jacket (not used for
these experiments). The sampling exhaust duct was connected to a stainless steel filter holder
61cm x 25.5cm x 2.5cm. The filter holder holds three 20.5cm x 25.5cm filters. The filter holder
was connected to an amber-glass coiled-condenser to cool the hot gas flowing before it entered
an amber-glass cartridge containing four polyurethane foam (PUF) cartridges of 10cm x 5cm
meant to capture semi-volatile organic compounds. Amber glass is important to note here since
many of the chemical species of interest in this study can be UV light sensitive. The PUFs were
retained by a fritted Teflon disk inside the cartridge. The gas exiting the PUFs was passed
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through an impinger which was connected to a vacuum pump and the gas exiting the pump was
directed to the cone calorimeter exhaust system through a wire reinforced vacuum tube.
At the beginning of each sampling period after assembling the sampling train, the system was
checked for leaks. Once any leaks were fixed, the air flow was set to 15 L/s by turning the
vacuum pump on and using a gate valve to control the air flow. All the circuit board laminate
samples tested were exposed to a heat flux of 50 kW/m2 or 100 kW/m2. For additional details on
the cone heater temperature (which is not the temperature that the samples encountered during
burning), see Appendix B: Experimental Conditions. Once the cone reached its set temperature,
the cone calorimeter ignition was turned on and samples were placed in the sample holder at the
center of the cone heater and ignited. Once the samples ignited, they were allowed to burn until
no flame and smoke were detectable. During sampling, the gas temperature inside the sampling
train was constantly monitored at eight different positions. The first two thermocouples (Tl and
T2) were placed inside the stainless steel duct at 5cm and 25.5cm from the exhaust hood above
the cone to monitor the gas temperature entering the duct (Tl) and entering the filter holder (T2).
The third thermocouple (T3) was placed at the outlet of the filter holder (or entrance of
condenser). The fourth thermocouple (T4) was positioned at the inlet of the PUF cartridge and
the fifth thermocouple (T5) was placed to monitor the gas temperature exiting the PUF cartridge.
The cold bath temperatures are adjusted to maintain the PUF cartridge exit gas temperatures (T5)
to ~20-25°C. However, the average gas temperatures exiting the PUFs were ~30°C for all
experiments. The other thermocouples were used to monitor the water bath temperatures for the
stainless steel duct water jacket, the condenser, and the glass cartridge water jacket. All
thermocouples used were 3mm sheath diameter, grounded, type K thermocouple probes from
Omega Engineering, Stamford, Connecticut. During sampling, the pressure dropped inside the
sampling train and the flow through the sampling train was constantly monitored by a digital
gauge manometer placed at the pump inlet and by a differential flow meter on the cone
calorimeter exhaust system, respectively. When the soot particles started to build up on the glass
filter and decreased the gas flowing through it, the flow was adjusted by opening the gate valve
situated at the inlet of the pump.
Post-sampling, the sampling train was disassembled; the condensate from the condenser was
recovered to a pre-cleaned container for analysis, the various components of the train were
covered with hexane-rinsed aluminum foil and transported to the recovery lab. In the recovery
lab, the filters and PUFs were removed, the filters were weighed to determine their PM loading
and the entire sampling train (from the hood and duct work above the cone/combustion zone) up
to the inlet of the impinger was rinsed with three solvents (methanol, methylene chloride and
toluene, respectively) to recover condensed material for analysis. All solvent rinses, condensate,
PUFs and filters were stored in pre-cleaned amber glass containers with Teflon lined caps; the
solvent levels were marked with the appropriate labels; and were refrigerated till they were either
shipped to the analytical lab or were analyzed at UDRI using GC/MS. The glass fiber filter and
PUF adsorbents were shipped to the Organic Support Laboratory (OSL) of EPA at RTF where
they were combined together, extracted, and analyzed for PxDD/Fs. After extraction, the OSL of
EPA at RTF shipped back a part of the PUF and Filter extract to UDRI to analyze for PAHs and
phosphorous-containing compounds. The analytical methods used to quantify involved isotope
dilution and internal standard procedures that are described later in Sections 3.6 through 3.8.
After the final solvent rinse (i.e., toluene), the metal duct and filter holder were rinsed with
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methylene chloride and covered with hexane-rinsed aluminum foil until the next experiment; the
glassware was rinsed with Sparkleen soap solution/deionized water and baked at 475°C for 8
hours in a Barnstead Thermolyne Pyro-clean Trace oven for baking glassware. After baking, the
glassware was rinsed with methylene chloride and covered with hexane-rinsed aluminum foil. A
field blank was performed to check for carry over and memory effects.
All fluorescent lights in the laboratory, as well as in the fume hood, were covered with clear UV-
absorbing filters supplied by UV Process Supply, Chicago, Illinois. This was done to
minimize/eliminate decomposition of UV light sensitive compounds from the pre-sampling
surrogates and samples recovered from the experiments. The three solvents used were toluene
(Envisolv, 34413) and Methanol (Pestanal, 34485) purchased from Sigma-Aldrich, Milwaukee,
Wisconsin and Methylene Chloride (Pestisolv, PS 724) purchased from Spectrum Chemicals,
New Brunswick, New Jersey at purity levels required as per EPA method 23 for analysis of
dioxins and furans. The 150 mm glass-microfiber filters (TE-EPM2000) without binder were
purchased from Whatman, USA. The PUFs were purchased from Tisch Environmental. The
PUFs and the filters were cleaned by the OSL at EPA, RTF by Soxhlet extraction with
methylene chloride for 16 hours and wrapped in aluminum foil, labeled, and shipped to UDRI in
airtight cans to use for sampling.
Pump outlet line connected to exhaust duct
Figure 3-7. Total Sampling Train Coupled with UDRI Cone Calorimeter
A-181
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&haust duct
3ip stream
sampling I ins
for hdoganated
ions analysis
sampling line
Note: the
s ampling line;
loci ions (for
iore analysis)
ar e subj act to
changes
based on
shakedown
experiments
1. 4' 304 S duct with walerjad
-------
r\
had to be tested; they were cut into 100cm square pieces. Four types of laminates were tested for
Phase II: laminate without flame retardant (NFR), laminate containing brominated flame
retardant (BFR), laminate containing halogen-free flame retardant (HFR), and laminate
containing halogen-free flame retardant (1556-HFR). The printed circuit board laminate samples
were tested at two different heat fluxes to mimic different combustion scenarios. The lower heat
r\
flux (50 kW/m ) was used to mimic an "open burn" type of event and the higher heat flux (100
kW/m2) was used to mimic an incinerator furnace condition that would be encountered during
incineration of the boards.
3.4 Sample Handling and Custody
3.4.1 Shipping Custody
Samples were collected at UDRI, packaged, and shipped by UPS to RTF. In RTF, the samples
were received and brought to the laboratory and then opened by the laboratory custodian. The
samples were stored in laboratory refrigerators until extraction. The sample custody form was
included in the shipping cooler, and the UPS records are the custody records for the transfer from
UDRI to RTF. The boxes and coolers were sealed with tape and the tape was removed in the
laboratory.
3.4.2 Sample Identification and Log
Each sample was given an identifying laboratory code number and name (laboratory ID). The
laboratory ID was assigned to the samples upon receiving and samples were logged in the
sample ID log book along with the sample name and project description. The code sequence was
explained to the laboratory personnel to prevent sample mislabeling. Proper application of the
code simplified sample tracking throughout the handling, analysis, and reporting processes.
Table 3-5 shows the laboratory ID coding that was used in this study. PUF and Filters were not
given separate numbers.
Table 3-5 Laboratory ID Coding System
YYMMXX
Laboratory
ID Code
YYMM
XX
Sample Type
Year and month of the sample logging in the laboratory system
Consecutive sample number of the given year (YY) and month (MM)
3.5 By-product Extraction
After the samples were collected and shipped back to RTF, the EPA OSL performed extraction,
cleanup, and fractionation of samples provided by UDRI. The extracts were analyzed using High
Resolution Gas Chromatography/High Resolution Mass Spectrometry (HRGC/HRMS) for target
PCDD/Fs and PBDD/Fs (Table 3-6). The results were reported in a spreadsheet to UDRI for
inclusion in the final report (results were reported as amounts per sampling train). In very early
samples, less than ten percent of the dioxins and furans were found in the sampler rinses and the
rinses would cause very high shipping costs, so only the PUF and filters from each sample were
sent to RTF for extraction and analysis.
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3.5.1 Organic Compound Target List
Chlorinated and brominated dioxins and furans (PCDD/Fs and PBDD/Fs, respectively) were
targeted in this project. Analysis concerned 2,3,7,8-substituted congeners of PCDD/Fs (17
congeners) and their brominated counterparts (only 13 2,3,7,8 PBDD/Fs congeners were reported
due to limited availability of commercial standards). Table 3-6 presents the congener-specific list
of PCDD/Fs and PBDD/Fs target analytes.
Table 3-6. PCDD/Fs and PBDD/Fs Target Analytes
Congener
Pattern
2,3,7,8
1,2,3,7,8
1,2,3,4,7,8
1,2,3,6,7,8
1,2,3,7,8,9
1,2,3,4,6,7,8
1,2,3,4,6,7,8,9
PCDD/Fs targets
TeCDD
PCDD*
HxCDD
HxCDD
HxCDD
HpCDD
OCDD
PBDD/Fs targets
TeBDD
PBDD
HxBDD
HxBDD
HxBDD
HpBDD
OBDD
2,4,6,8
TeCDF
***
TeBDF
TeBDF**
PBDF
PBDF
HxBDF
***
1,2,3,7,8 PCDF
2,3,4,7,8 PCDF
1,2,3,4,7,8 HxCDF
1,2,3,6,7,8 HxCDF
1,2,3,7,8,9 HxCDF* ***
2,3,4,6,7,8 HxCDF* ***
1,2,3,4,6,7,8 HpCDF HpBDF
1,2,3,4,7,8,9 HpCDF ***
1,2,3,4,6,7,8,9 QCDF OBDF
* Were reported as co-elution.
** FromTeBDF homolog group 2,4,6,8 -TeBDF can be reported because it was present in the calibration solution
and therefore has an accurate retention time.
*** In the various calibration solutions, 18 different congener patterns were included, e.g. 2,3,7,8. Of the 18
individual congener patterns that were looked for, five were only in one of the solutions (either bromo or chloro).
3.5.2 EPA-RTP Experimental Strategy
Figure 3-9 presents the original experimental strategy for RTF's part of the project. The first
phase of this project was extraction, cleanup and fractionation (described in detail in Section
3.5.3 and Section 3.5.4 of this report) of samples provided by UDRI for HRGC/HRMS
instrumental analysis of PCDD/Fs and PBDD/Fs. The second phase described in detail in Section
3.6.2 was the instrumental analysis. The third phase of the analysis was data processing and
reporting (see Section 3.6.3 for details).
A-184
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Spiking samples with 13C-labeled internal standard
See Table for composition of pre-extraction spikes
Sequential Soxhlet extraction
3.5 h DCM, 16h toluene
Concentration of the extract
three-ball Snyder columns, filtration, concentrated further in nitrogen to 1 ml
1/4 extract
Solvent exchanged to hexane
Pass sample through ABN-silica column
until clear at 0.5 ml
1/4 extract
Solvent exchanged to hexane
Pass sample through ABN-silica column
until clear at 0.5 ml
Sample loaded through silica onto alumina
Wash through silica and alumina column
90 ml in hexane; forward, 8 ml/min
Wash of alumina column
60 ml 2% DCM in hexane; forward, 10 ml/min
Elution from alumina to carbon column
120 ml 50% DCM in hexane; forward, 10 ml/min
Wash of carbon column
4 ml 50% ethyl acetate in benzene; forward, 10 ml/min
Elution from carbon column
75 ml toluene; reverse, 5 ml/min
HEI
PCDD/F fraction
---T-""
Sample loaded through silica onto alumina
Wash through silica and alumina column
90 ml in hexane; forward, 8 ml/min
Wash of alumina column
60 ml 2% DCM in hexane; forward, 10 ml/min
Elution from alumina column
100 ml 100% DCM; forward, 10 ml/min
PBDD/F fraction
Spiking samples with ISC-labeled pre-injection spike
See Table for composition of pre-injection spikes
HRGC/HRMS analysis
Data analysis and reporting
Figure 3-9. Original RTF Experimental Strategy.
The actual work added a step to the PCDD/Fs cleanup and dropped the PBDD/Fs cleanup.
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3.5.3 Same-Sample Extraction of PCDD/Fs and PBDD/Fs
Extraction of sampling trains for PBDD/Fs and PCDD/Fs measurements was performed by
sequential Soxhlet extraction: overnight (16 hours) with methylene chloride, followed by
overnight (16 hours) extraction with toluene. This project had such a large sample volume that
the regular 3.5 hours methylene chloride extraction did not give enough cycles for the extraction.
Before extraction, samples were spiked with the internal standard mixtures. Pre-extraction spikes
were purchased from Cambridge Isotope Laboratories Inc., Andover, Massachusetts (EDF-5408,
EDF-4137A). The composition of 13C-labeled PCDD/Fs and PBDD/Fs pre-extraction internal
standard mixes is given in Table 3-7 and Table 3-8. All solvents were
HPLC/GC/spectrophotometry grade ACS/HPLC certified (Burdick and Jackson, Honeywell,
Muskegon, Michigan).
3.5.4 Cleanup and Fractionation of PCDD/Fs and PBDD/Fs
For determination of PBDD/Fs and PCDD/Fs, one-quarter of the extract was cleaned and
fractionated using an automated liquid chromatography multicolumn Power Prep/Dioxin System
(FMS Fluid Management Systems, Inc., Watertown, Massachusetts). One-twentieth of the
extract was sent to UDRI for further analysis of other target compounds. The remainder of the
extract was archived. Prior to the automated cleanup process, extracts were concentrated and
then diluted in hexane, causing precipitation of non-dioxin-like compounds that could have
caused interferences in the analysis. This step was repeated until no more precipitate formed and
the extract was less than ten percent toluene. The extracts were then loaded and pumped
sequentially through individual sets of FMS proprietary columns. Acidic and multilayer silica,
carbon, and alumina columns were pre-packed, disposable cartridges available from FMS Fluid
Management Systems, Inc., U.S.A. The previous experiments on HRGC/HRMS analysis of
some combustion-related matrices showed interferences from other compounds that interfere
with quantitative determination of the target compounds (PCDD/Fs and PCBs)1. This
interference necessitates the introduction of an additional cleanup step, prior to the usual2
automated PowerPrep liquid chromatography cleanup used in the OSL for same-sample
determination of PBDD/Fs and PCDD/Fs from combustion flue gas. The additional step
involved passing the extract through a large acidic silica gel column for the cleanup of the raw
extract and concentration of the eluate to 0.5ml. This additional cleanup step was repeatedly
performed until the extract was clear at 0.5ml volume. If the extract was not clear the eluate was
diluted to 12ml with hexane and processed again. This clear 0.5ml of extract was then diluted to
12ml in hexane and processed through multilayer silica (4g acid, 2g base, and 1.5g neutral)
column, followed by a basic alumina (llg) column and also a carbon column (0.34g).
Composition of elution solutions and elution volumes are presented in Figure 3-9 of this report.
To quantitate the PBDD from a single aliquot of extract, an additional step was added after the
toluene elution of the carbon column, in which the alumina column was washed with 100ml of
methylene chloride and that eluate was concentrated and exchanged into decane. In the later
samples this portion was analyzed separately. It has been determined since the 2009 publication2
that a separate FMS cleanup for the PBDD/Fs was not necessary, just this additional alumina
1 Data not published, information archived and available from OSL.
2 Tabor D., Gullett B.K., Same-Sample Determination of Ultratrace Levels of Polybromodiphenylethers,
Polybromodibenzo-p-dioxins/Furans, and Polychlorodibenzo-p-dioxins/Furans from Combustion Flue Gas. Anal.
Chem. 2009, 81, 4334-4342
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column wash. Also, the removal of the carbon column step completely (as was done previously)
was considered insufficient cleanup for most samples. The final eluates were then spiked with
pre-analysis compounds, and then decane was concentrated to a final volume of about 25|il.
3.6 Dioxin/Furan Analysis
3.6.1 HRGC/HRMS Calibration and Maintenance
EPA methods require that a laboratory record be maintained of all calibrations, including daily
calibration checks. These daily checks ensure continued reliable operation and provide the
operator warnings of abnormal operation.
The following calibration activities were conducted:
• Daily optimization of the HRMS instrument was carried out using a perfluorokerosene
(PFK) calibration standard; static resolving power checks were performed before and
after data acquisition to demonstrate the required resolution of 10 000 (5% valley).
• Bromodioxin/furan and chlorodioxin/furan calibration standard solutions (please see
Section 3.5.1. for details) were used for the initial calibration of the HRGC/HRMS. The
medium concentration standard was used for calibration verification according to
requirements of U.S. EPA M-23.3
• The daily calibration was acceptable if the concentration of each labeled and unlabeled
compound is within the calibration verification limit of 25-30%. If all compounds met the
acceptance criteria, calibration was verified and analysis of standards and sample extracts
proceeded. When any compound failed its respective limit, recalibration for all congeners
was performed. In addition, the ion abundance ratios were within the allowable control
limits of 15%.
Instrument maintenance was conducted as recommended by the manufacturer and on an as-
needed basis. Replacement parts, including columns and filaments, were maintained in the
laboratory to minimize downtime. Service engineers' visits were utilized in major failure
situations and for annual preventive maintenance.
3.6.2 HRGC/HRMS Analysis
For analysis of tetra- through octa-BDD/Fs, the GC was equipped with 15m DB-5 (0.25um film
thickness x 0.25mm i.d.) column (J&W Scientific, Folsom, California). For analysis of tetra-
through octa-CDD/Fs, a 60m RTX-Dioxin-2 (Restek, Bellefonte, Pennsylvania) column was
used (0.25um film thickness x 0.25 mm i.d.).
The GC oven temperature for PBDD/Fs analysis was programmed from 130°C to 320°C at
10°C/min (21 minute hold). The temperature program for PCDD/Fs went from an initial
temperature of 150°C to 260°C at 10°C/min with a final hold time of 55 minutes. The carrier gas
(helium) flow rates were 1 and 1.2ml/min for PBDD/Fs and PCDD/Fs, respectively. The
PCDD/Fs flow was ramped to 1.5ml/min after 15 minutes. Two microliters (2uL) of the extract
3 U.S. EPA Test Method 23. Method 23 - Determination of Polychlorinated Dibenzo-p-dioxins and Polychlorinated
Dibenzofurans from Municipal Waste Combustors; Office of Solid Waste and Emergency Response, Environmental
Protection Agency: Washington, DC, 1996.
A-187
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was injected under splitless mode (injection port temperature set as 300°C and 270°C for
brominated and chlorinated targets, respectively).
The HRMS was operated in an electron ionization (35 eV and 650 uA current) selective ion
recording (SIR) mode at resolution R > 10 000 (5% valley). The temperature of the ion source
was 280°C for the PBDD/Fs analyses, whereas for PCDD/Fs, the ion source was kept at 250°C.
The two strongest ions in the molecular cluster were monitored in every retention time window
for each native and labeled PBDD/Fs and PCDD/Fs based on mass spectroscopy libraries and
literature data, unless interferences are present. Peak responses for each of the two selected
molecular ion clusters must be at least 2.5 times the noise level (S/N > 2.5), otherwise the
compound was considered below the limit of detection. The bromine/chlorine isotope ratio for
the two molecular ion clusters was within ±15% of the correct isotope ratio, if not they were
flagged EMPC (Estimated Maximum Possible Concentration).
The standards used for PBDD/Fs identification and quantification were a commercially available
set of calibration standards that contained native target tetra- through octabromodioxins and/or
furans at concentrations from 0.4 to 4.0 (CS-2) through 50-500 (CS-5) ng/ml depending on the
degree of bromination (EDF-5407, CIL Cambridge Isotope Laboratories Inc., U.S.A.). The
standards used for chlorinated dioxin/furan identification and quantification were a mixture of
standards containing tetra- to octa-PCDD/Fs native and 13C-labeled congeners designed for
modified U.S. EPA Method 23 (ED-2521, EDF-4137A, EDF-4136A, EF-4134, ED-4135, CIL
Cambridge Isotope Laboratories Inc., U.S.A.). The PCDD/Fs calibration solutions were prepared
in house and contain native PCDD/Fs congeners at concentration from 1 (ICAL-2)-20 (ICAL-6)
ng/ml.
3.6.3 Data Processing and Reporting
For the data collection, Mass Lynx software (Waters, Milford, Massachusetts), version 4.1 was
used (including Target Lynx 4.1. for processing and quantitation). Data processing included not
only the determination of PCDD/Fs and PBDD/Fs concentrations, but also the determination of
the method detection and quantitation limits (LOD and LOQ, respectively). Every set of data was
reported as ng per train. For PCDD/Fs analysis, data would have been reported as ng-TEQ per
train, if the analyses were accepted (pre-sampling surrogate problems will be detailed later).
3.6.4 Quality Assurance/Quality Control
The data quality objectives (DQOs) define the critical measurements needed to address the
objectives of the test program, and specify tolerable levels of potential errors associated with
data collection as well as the limitations of the use of the data. The data quality indicators (DQIs)
are specific criteria used to quantify how well the collected data meet the DQOs. The DQI goals
for the critical measurements correspond to and are consistent with the standards set forth in each
respective referenced EPA Method. DQI goals will correspond to recovery criteria of the labeled
standards in the respective reference methods. The DQI goals specified for the respective
sampling method used by UDRI sampling team, such as pre-sampling surrogates recoveries are
not included in the DQOs, but were reported to UDRI, along with quality criteria guidelines.
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Composition of labeled pre-sampling (surrogate standards), pre-extraction (internal standards)
and pre-injection (recovery standards) spiking solutions are given in Table 3-7 and Table 3-8.
Table 3-7. Composition of the PCDD/Fs Sample Spiking Solution
Spiking Solution
Analytes
Concentration (jig/ml) Special Notes
Surrogate standards
(Field spikes)
EDF-4136A*
37Cl4-2,3,7,8-TCDD
13C12-l,2,3,4,7,8-HxCDD
13C12-2,3,4,7,8-PeCDD
13C12-l,2,3,4,7,8-HxCDF
13C12-l,2,3,4,7,8,9-HpCDF
1.25
2.5
2.5
2.5
2.5
Added to the sample prior to
sampling
Internal standards
EDF-4137A*
Recovery Standards
ED-2521*
13C12-2,3,7,8-TCDD
13C12-l,2,3,7,8-PeCDD
13C12-l,2,3,6,7,8-HxCDD
13C12-l,2,3,4,6,7,8-HpCDD
13C12-OCDD
13C12-2,3,7,8-TCDF
13C12-l,2,3,7,8-PeCDF
13C12-l,2,3,6,7,8-HxCDF
13C12-l,2,3,4,6,7,8-HpCDF
13C12-1,2,3,4-TCDD
13C12-l,2,3,7,8,9-HxCDD
1.25
2.5
2.5
2.5
5
1.25
2.5
2.5
2.5
5
5
Added to the sample prior
extraction
Added to extracts prior
analysis
to
to
*Commercially available from CIL Cambridge Isotope Laboratories Inc., U.S.A.
Table 3-8. Composition of the PBDD/Fs Sample Spiking Solution
Spiking Solution
Analytes
Concentration (ng/ml) Special Notes
Surrogate standard
(Field spikes)
EF-5410*
13,
C12-l,2,3,4,7,8-TeBDF
100
Added to the sample prior
to sampling
Internal standards
EDF-5408*
Recovery Standards
EDF-5409*
13C12-2,3,7,8-TBDD
13C12-l,2,3,7,8-PeBDD
13C12-l,2,3,4,7,8-HxBDD
13C12-l,2,3,6,7,8-HxBDD
13C12-l,2,3,4,6,7,8-HpBDD
13C12-OBDD
13C12-2,3,7,8-TBDF
13C12-2,3,4,7,8-PeBDF
13C12-l,2,3,4,7,8-HxBDF
13C12-l,2,3,4,6,7,8-HpBDF
13C12-OBDF
13C12-l,2,3,7,8-PeBDF 13C12-
1,2,3,7,8,9-HxBDD
100
100
250
250
500
750
100
100
250
500
750
100
250
Added to the sample prior
to extraction
Added to extracts prior to
analysis
*Commercially available from CIL Cambridge Isotope Laboratories Inc., U.S.A.
3.6.5 Pre-Sampling Spikes Quality Criteria and Performance
A group of carbon-labeled PBDD/Fs and PCDD/Fs congeners (Table 3-7. and Table 3-8) were
added to the PUF sorbent before the sample was collected in UDRI. The surrogate recoveries
were measured as relative to the internal standards and were a measure of the sampling train
collection efficiency.
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OSL provided results of pre-sampling spikes recovery to UDRI, using the acceptance criteria
outlined in Table 3-9.
Table 3-9. Pre-Sampling Spike Recovery Limits [%]
Pre-sampling spike
Minimum
Maximum
PCDD/Fs % %
37Cl4-2,3,7,8-TeCDD
13C12-2,3,4,7,8-PCDF
13C12-l,2,3,4,7,8-HxCDF
13C12-l,2,3,4,7,8-HxCDD
13C12-l,2,3,4,7,8,9-HpCDF
70.0
70.0
70.0
70.0
70.0
130
130
130
130
130
PBDD/Fs % %
13C12-l,2,3,4,7,8-TeBDF
70.0
130
The pre-sampling surrogates recovery acceptance criteria were as recommended by U.S. EPA
Method 23 for chlorinated dioxins.4 There is no standard method guidance for PBDD/Fs pre-
sampling surrogates recovery; hence Method 23 acceptance criteria were used for brominated
targets.
Upon analysis of the PCDD/Fs samples, the pre-sampling surrogates were found to be absent
from seven of the ten samples requested for PCDD/Fs analysis. Because this constituted a large
majority of the PCDD/Fs samples and that there were no PCDD/Fs detected in the first phase of
this project, the investigators decided not to report PCDD/Fs data. In the samples that were
analyzed, there were virtually no PCDD/Fs detected consistent with the first phase of the project
but it would be consistent with complete loss of target compounds which is highly unlikely given
the PBDD/Fs data. Given both of these possibilities, not reporting the data was of the most
objective action.
There was significant brominated interference in 6 of 18 tests. The six tests with bromine
interference were all the samples that had standard halogen-containing ground components
added. This reduced the number of measured experimental samples to 12. In the PBDD/Fs
samples there was also a brominated pre-sampling surrogate. The recoveries for the 12 samples
ranged from 0.8% recovery to 234% recovery. Four samples appear to have been double-spiked
with recoveries near 200% and the sample near 0% recovery was probably not spiked. Five of
the remaining samples were between 90 and 110% recovery. The other two samples had low
recovery which was not likely due to spiking problems.
3.6.6 Pre-Extraction Spikes Quality Criteria
A group of 11 PBDD/Fs and 9 PCDD/Fs 13C-labeled internal standards (see Table 3-7. and Table
3-8), representing the tetra- through octa-halogenated homologs, were added to every sample
4 U.S. EPA Test Method 23. Method 23 - Determination of Polychlorinated Dibenzo-p-dioxins and Polychlorinated
Dibenzofurans from Municipal Waste Combustors; Office of Solid Waste and Emergency Response, Environmental
Protection Agency: Washington, DC, 1996.
A-190
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prior to extraction. The role of the internal standards is to allow quantification (via the isotope
dilution internal standard methodology) of the native targets in the sample as well as to
determine the overall method efficiency.
Recovery criteria for the internal standards of PBDD/Fs and PCDD/Fs are given in Table 3-10.
Table 3-10. Pre-Extraction Spike Recovery Limits [%]
Pre-extraction spike
PCDD/Fs
13C12-2,3,7,8 TeCDF
13C12-2,3,7,8 TeCDD
13C12-1,2,3,7,8 PCDF
13C12-1,2,3,7,8 PCDD
13C12-1,2,3,6,7,8 HxCDF
13C12-1,2,3,6,7,8 HxCDD
13C12-1,2,3,4,6,7,8 HpCDF
13C12-1,2,3,4,6,7,8 HpCDD
13C12-1,2,3,4,6,7,8,9 OCDD
PBDD/Fs
13C12-2,3,7,8-TBDF
13C12-2,3,7,8-TBDD
13C12-2,3,4,7,8-PeBDF
13C12-l,2,3,7,8-PeBDD
13C12-l,2,3,4,7,8-HxBDF
13C12-l,2,3,4,7,8-HxBDD
13C12-l,2,3,6,7,8-HxBDD
13C12-l,2,3,4,6,7,8-HpBDF
13C12-l,2,3,4,6,7,8-HpBDD
13C12-OBDD
13C12-OBDF
Minimum
%
40.0
40.0
40.0
40.0
40.0
40.0
25.0
25.0
25.0
%
40.0
40.0
40.0
40.0
40.0
40.0
40.0
25.0
25.0
25.0
25.0
Maximum
%
130
130
130
130
130
130
130
130
130
%
130
130
130
130
130
130
130
130
130
130
130
The pre-extraction internal standard recovery acceptance criteria were as recommended by U.S.
EPA Method 23 for chlorinated dioxins.5 There is no standard method guidance for PBDD/Fs
pre-extraction internal standards recovery; U.S. EPA Method 23 criteria were therefore used for
brominated targets.
5 U.S. EPA Test Method 23. Method 23 - Determination of Polychlorinated Dibenzo-p-dioxins and Polychlorinated
Dibenzofurans from Municipal Waste Combustors; Office of Solid Waste and Emergency Response, Environmental
Protection Agency: Washington, DC, 1996.
A-191
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As was mentioned before, the PCDD/Fs results were considered not reportable and the pre-
extraction results are not reported as well.
The brominated pre-extraction spikes mostly passed the PCDD/Fs criteria up to the hexa
congeners but the hepta and octa congeners were frequently below the PCDD/Fs criteria
although detectable. In the original QAPP, the table for the PBDD/Fs pre-extraction spike
criteria was not the table of criteria specified in the Method 23 for PCDD/Fs pre-extraction
spikes (Table 3-10).
3.7 Polyaromatic Hydrocarbon Analysis
Combustion by-products were collected into PUF and filter and Soxhlet extracted using both
methylene chloride and toluene, yielding two separate samples for analysis. The sampling train
was also rinsed sequentially with methanol, methylene chloride, and toluene following each
experiment to collect any by-products that may not have been collected by the PUF or filter. The
methanol rinse was solvent extracted with the methylene chloride rinse (liquid-liquid extraction)
and separated, yielding two separate samples from the three rinses. Therefore, UDRI tested four
different sample media for the presence of PAHs: (1) methylene chloride from methanol and
methylene chloride rinses, (2) toluene rinse, (3) methylene chloride Soxhlet extraction of PUF
and filter, and (4) toluene Soxhlet extraction of PUF and filter. Using samples from brominated
laminate tests, the PAH content of the rinses were compared to the PAH content of the PUF/filter
extracts. Methylene chloride and toluene rinses from experiments with BFR + P - 50 (E6), BFR -
100 (E15), and BFR + PHF - 50 (E30) were analyzed (for Experiment # see Appendix B:
Experimental Conditions). Experiment BFR - 100 (El5) was used to analyze the toluene rinse
and was compared to the extract. For methylene chloride, most of the PAHs (EPA list of priority
PAHs) in the rinse were estimated to be <10% of the magnitude of the PAHs from the extract.
This excludes naphthalene and compounds lighter than fluorine where breakthrough was likely.
The naphthalene and lighter compounds were less than 1% in the rinses when compared to the
PUF/filter extracts. Even in the extract, the naphthalene signal was significantly smaller than the
other PAHs detected probably due to breakthrough through the PUF. UDRI found -90% of the
PAHs to be in the methylene chloride extracts compared to <10% in the methylene chloride
rinses. The level of PAHs detected in the toluene extract was <1% and in the toluene rinse was
<0.1%. These findings and budgetary constraints led the researchers to decide to only analyze the
methylene chloride extracts. PAHs were thus only measured for the methylene chloride
extraction samples for the remainder of the project.
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3.8 Organophosphorus and Chlorinated Benzene/Phenol Analysis
The chromatograms from PAH analysis were used to generate library search reports to determine
the presence of organophosphorous compounds. In addition, since no attempt was made to
analyze for chlorinated dioxins and furans due to reasons explained in Section 3.6.5, an attempt
was made to determine the presence of chlorinated benzenes and phenols known to be precursors
for the formation of halogenated dioxins and furans. The following integration events were used
when generating the library search reports: initial area reject at 1%; initial peak width of 0.02;
shoulder detection off; initial threshold of 16. The compound with the highest match quality is
reported for the compounds detected.
4 Results and Discussion
The purpose of this study as part of the U.S Environmental Protection Agency (EPA) Design for
the Environment (DfE) program was to understand the potential emissions of halogenated
dioxins or furans, and polyaromatic hydrocarbons (PAHs) from burning circuit board laminates.
This objective was achieved by using the cone calorimeter to expose circuit board laminates to
simulated combustion scenarios under ventilated fire conditions (15 L/s) at two heat fluxes (50
kW/m2 and 100 kW/m2). The 50 kW/m2 heat flux was chosen to mimic open burn conditions
when circuit boards are improperly burned for precious metal recovery. The higher heat flux, 100
kW/m2, was chosen to mimic incineration conditions that would be used to recover/smelt away
precious metals and properly dispose of e-waste. Since the sampling train for this study
prevented the normal collection of oxygen consumption calorimetry data (Sections 3.3.1 to
3.3.3), experiments were done using the normal cone calorimeter exhaust system to collect data
for heat release (see Appendix A: Circuit Board Flammability Data), smoke yield, fire safety
information, oxygen consumption rates, CO/CO2 production rates, and effective heats of
combustion needed to attempt to correlate back to observed emission products. The emphasis of
this section of the report is on the emissions observed from the cone calorimeter (smoke,
CO/CO2) which will then be later compared to the emissions data collected from the sampling
train.
4.1 Total Mass Burned
The total mass of each type of printed circuit board laminate sample burned for the cone
calorimeter total sampling train experiments is given in Table 4-1. Total mass is important for
determining emissions factors; the amount of flammable mass burned will determine how much
total emissions are obtained.
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Table 4-1. Total Mass Burned Per Sample
Sample Description-Heat Flux (kW/m2)
BFR - 50
BFR - 50
BFR - 100
BFR - 100
BFR + P - 50
BFR + P - 50
BFR + PHF - 50
BFR + PHF - 50
HFR - 50
HFR - 50
HFR - 100
HFR - 100
HFR + P - 50
HFR + P - 50
HFR + PHF - 50
HFR + PHF - 50
1556 HFR - 50
1556 HFR - 50
1556HFR + P-50
1556HFR + P-50
1556 HFR + PHF -50
1556 HFR + PHF -50
NFR-50
NFR-50
NFR - 100
NFR - 100
Total Mass Burned per Sample (g)
11.8
13.6
14.3
15
20
20.4
18.2
17.3
8.9
8.1
13.3
13.3
18.1
19.8
19.6
18.6
9.3
9.7
17.9
17.8
16.4
15.9
16.5
15.6
7.9
8.8
4.2 Smoke
Smoke data obtained using the standard cone calorimeter (without the total sampling train) for all
of the printed circuit board samples are shown in Table 4-2. Total smoke release was affected by
both component blend and flame retardant chemistry, with flame retardant chemistries always
having higher smoke release than the non-flame retardant samples. It should be noted that smoke
release in the cone calorimeter is a simple light obscuration measurement and may be composed
of many different components. While smoke is a good indication of incomplete combustion, its
presence cannot be directly correlated to emissions of concern (PM, PAH, dioxins, etc.). Instead,
smoke provides some insight into likely emissions trends from the different flame retardant
chemistries.
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Table 4-2. Smoke Release Data
Sample Description-Heat Flux (kW/m2)
NFR-50
BFR - 50
HFR - 50
1556 HFR - 50
NFR - 100
BFR - 100
HFR - 100
BFR + P-50
HFR + P - 50
1556 HFR + P-50
BFR + PHF-50
HFR + PHF - 50
1556 HFR + PHF -50
Average smoke release.
N=3 per sample*
(m2/m2)
222.03
479.10
250.80
246.33
214.73
439.77
264.83
691.80
438.53
397.43
468.13
353.43
309.23
* Raw data listed in appendix
The smoke release information is also presented in Figure 4-1 and the following conclusions can
be made.
Brominated Flame retardant (BFR) - When compared to the other chemistries, BFR smoke
release was more than 50 to 90% greater than HFR samples. This is expected due to the flame
retardant mechanism of BFR which inhibits vapor phase combustion and in turn creates more
smoke. As heat in the flame increases due to higher heat flux, more of the smoke should burn
away and total smoke should decrease; this is observed in Figure 4-1.
Halogen-Free Flame retardant (HFR) and 1556 Halogen-Free Flame retardant (1556 HFR)
- Due to the mechanism of flame retardancy, which should be condensed phase char formation
assuming that the halogen-free flame retardants are phosphorus-based, lower smoke release is
observed compared to the BFR laminates. Unlike the BFR laminates, as heat flux is increased for
HFR, a slight increase (5.6 %) in total smoke was observed compared to NFR(-4.6%). This may
be due to the fact that the higher heat flux of burning is causing more of the PAHs in the char of
the samples to become pyrolyzed and form soot and condensed phase soot precursors. However,
this difference between NFR and HFR samples is within the percentage error of the cone
calorimeter smoke measurement device (± 10%). The difference should be considered with
caution even though the trend was reproducible with the triplicate cone calorimeter experiments
conducted.
No Flame retardant (NFR) - These materials show the lowest smoke release as expected since
they have no flame retardants present. However, the difference compared to HFR is within the
margin of error of the measurement device as described above.
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Halogenated and Low-Halogen Components - The addition of powdered components produced
variable smoke release results (-2.2 to 74.6 %) compared to the laminates alone. For example,
the addition of halogen containing components to BFR increased smoke by 44.2%, but when
low-halogen component powders were present, total smoke was reduced by 2.2%. The addition
of halogen containing components to halogen-free laminates provided the highest increases in
smoke release 74.6% and 61.3% for FIFR and 1556 FIFR laminates respectively. Halogen-free
component powders yielded a smaller increase in smoke compared to the halogen-containing
component powders, with a reduction in total smoke (2.2%) seen with BFR laminates, and only a
40.9% and 25.6% increase for FIFR and 1556 FIFR laminates respectively. The extra flammable
mass in both powders contributes to some smoke from burning, but the presence of halogen
increased smoke release even more.
Total Smoke Release
800.00
\ \ \
_
01
OC
300.00
o
jj 200.00
100.00
0.00
Sample Description
Figure 4-1. Smoke Release Plot
4.3 CO/CO2 Emissions
The brominated FR laminates, with or without components, show lower emissions of CC>2 than
the other sample types (1.05 to 1.28 kg/kg compared to 1.3 to 1.62 kg/kg for HFR and 1.85 and
1.67 kg/kg for NFR) (Table 4-3 and Figure 4-2). Less total CC>2 is observed because bromine
inhibits full combustion of carbon to CC>2. However, a significant increase in CO is not always
observed with the samples tested in this study when CC>2 emissions decrease. Therefore, the data
only support the idea that the brominated FR compounds reduce total CC>2 emissions when
A-196
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combusted under open burn (50 kW/m heat flux) or incinerator (100 kW/m heat flux)
conditions. The mass balance of emissions must lie in other gases and compounds if the CO2
emissions are lower. The non-halogenated FR laminates have similar CO yields when compared
to the BFR compounds, but higher CC>2 yields. This makes sense in that the flame retardants are
causing more char formation, which would lower the total amount of carbon that is combusted.
Since the non-halogenated laminates do not contain halogens that can affect combustion
chemistry, CC>2 yields should be higher. The non-flame retardant samples burn with the highest
CO2 yields but have CO emissions roughly equal to or higher than the other flame retardant
systems when burned at low heat flux (50 kW/m2). This is because in the flame retardant
systems, potential carbon is present as PAHs and soot rather than being partly oxidized. Total
mass burned (total potential carbon that could convert to CO or CO2; see Table 4-1) does not seem
to correlate well to average CO and CO2 emissions, allowing combustion chemistry of the
boards, flame retardants, and components to explain to CO/CO2 emissions factors.
Table 4-3. CO/CO2 Emission Factors
Sample Description-Heat Flux (kW/m2)
BFR - 50
BFR - 100
BFR + P-50
BFR + PHF-50
HFR - 50
HFR - 100
HFR + P - 50
HFR + PHF - 50
1556 HFR - 50
1556 HFR + P-50
1556 HFR + PHF -50
NFR-50
NFR - 100
Av Post Ignition
CO Yield
CO2 Yield
(kg/kg)
0.15
0.14
0.13
0.14
0.18
0.11
0.16
0.12
0.12
0.10
0.10
0.20
0.07
1.05
1.06
1.12
1.28
1.59
1.44
1.50
1.52
1.42
1.30
1.62
1.85
1.67
A-197
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Post Ignition CO/CO2 Emission Factors
Av Post Ignition
CO Yield
Av Post Ignition
CO2 Yield
Sample Description
Figure 4-2. CO/CO2 Emission Factors Plot
4.4 Particulate Matter Emissions
The cone calorimeter data (Table 4-4 and Figure 4-3) demonstrates that most of the samples have
similar PM emissions when components are present, but can vary depending on base resins. The
halogen-free flame retardant (HFR) at 50 kW/m2 has the highest level (40% higher than BFR 50
kW) of PM emitted during burning. This relates to the condensed phase mechanism of action,
where the phosphorous flame retardant reacts with the polymer and is involved in its charring.
These charred and cross-linked polymer components will have chemical structures similar to
soot precursors, and as those molecules pyrolyze off the surface of the burning circuit board,
higher amounts of PM may be seen. The BFR compounds do show some higher PM emissions
when compared to the NFR and FIFR + component blends. While smoke yields were higher for
BFR compounds compared to other sample types (Table 4-2 and Figure 4-1), PM was not always
higher for BFR. This may simply indicate that the smoke produced by burning BFR materials is
not captured by the PM filters in our experiments or that the smoke measured by the cone
calorimeter system was not a particulate but was instead organic vapors which obscured light.
Table 4-4. PM Emission Factors
Sample Description-Heat Flux (kW/m2)
BFR - 50
BFR - 100
BFR + P - 50
BFR + PHF-50
HFR - 50
PM, g/kg fuel in
24.05
23.11
22.66
20.85
33.48
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Sample Description-Heat Flux (kW/m2)
HFR - 100
HFR + P - 50
HFR + PHF - 50
1556 HFR - 50
1556 HFR + P-50
1556 HFR + PHF -50
NFR-50
NFR - 100
PM, g/kg fuel in
21.02
18.59
19.32
23.54
17.93
13.42
17.28
17.70
PM Emission Factors
Sample Description
Figure 4-3. Particular Matter (PM) Emission Factors
4.5 PBDD/Fs and PCDD/Fs Emission Factors
Printed circuit board combustion at UDRI generated 42 samples for analysis. Not all samples
were analyzed for PCDD/Fs and PBDD/Fs due to resource limitations; instead a relevant subset
of samples was selected for analysis. The laminate samples containing brominated flame
retardant tested at 50 kW/ m2 alone and with halogenated components or with low halogen
components, and at 100 kW/m2 alone, and the necessary blanks were analyzed for PCDD/Fs and
PBDD/Fs. This approach resulted in nine samples being selected for PCDD/Fs analysis, and 14
A-199
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samples selected for PBDD/Fs analysis at EPA. Due to problems with the pre-sampling spike,
the PCDD/Fs analysis was not quantitated. In the PBDD/Fs analysis, four blanks were added to
the fourteen samples selected, yielding 18 samples. Of the 18 total samples, 12 were able to be
quantitated. The six samples that could not be quantitated were of brominated flame retardant
with halogenated components. The quantitation could not be done due to significant interference
that caused the internal standards to not be useable for quantitation. Analysis of one sample on a
LRMS in full scan resulted in insufficient sensitivity to identify the compound emissions.
PBDD/Fs compounds were quantitated in 12 samples. Six of these samples were BFR laminates
and six were combustion blanks. Five of the six blanks had significantly lower levels of
PBDD/Fs compared to the laminate samples. For the higher concentrated PBDD/Fs detected, the
difference in detection level between the combustion blanks and the BFR laminates was as large
as a factor of 100. For example, the detection of 1,2,3,4,6,7,8 - HpBDF in all but the first blank
ranged from not detected to 0.3 ng/train compared to 4 to 9 ng/train for the six BFR laminate
samples. In a system that is as complex as the calorimeter and has as many reused parts very low
levels in the actual heated calorimeter blanks are not surprising.
The chromatographic peaks for the 2,3,7,8 congeners were small compared to the non-2,3,7,8
congeners based on visual confirmation. This finding was confirmed by quantification of a single
non-2,3,7,8 congener. 2,4,6,8-TeBDF congener was a factor of four higher than the highest of
the 2,3,7,8-Br-substituted toxic congeners in the samples. Other visible brominated compounds
in the chromatograms were of similar concentrations.
The total PBDD/Fs emission from the cone calorimeter experiments shown in Table 4-5 and
Figure 4-4 indicate that brominated flame retardant (BFR) laminates have higher total PBDD/Fs
emission factors than brominated flame retardant laminates with halogen-free components. For
all six brominated samples, PBDD/Fs were released in the range of 1.89 to 4.14 ng/g (Table 4-5)
with variability that suggests there is no large difference between each sample based on only
N=2. Figure 4-4 is based on the average emission factors and suggest differences in the samples
that cannot be conclusive without larger sample sizes.
Brominated dioxins and furans were not analyzed in the NFR and HFR systems since these
systems were free of brominated FR structures (TBBPA) that could have formed PBDD/Fs
compounds.
Interestingly, the addition of components did not appear to increase PBDD/Fs emissions. This
may due to (1) a chemical interaction between the halogen-free component powder and
PBDD/Fs, (2) a dilution effect from the additional non-halogenated mass burned contributing to
the total mass lost used in the emission factor calculation, or (3) a combination of both. At this
time, it is not be possible to clearly discern given the data scatter between the replicates shown in
Table 4-5.
Based on the available data, the conclusion is that PBDD/Fs are detected in the emissions of
these brominated samples.
A-200
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Table 4-5. PBDD/Fs Emission Factors
Analyte
ND=0,EMPC=EMPC
2,3,7,8 - TBDD
1,2,3,7,8 -PeBDD
1,2,3,4,7,8 + 1,2,3,6,7,8 - HxBDD
1,2,3,7,8,9 -HxBDD
1,2,3,4,6,7,8 -HpBDD
1,2,3,4,6,7,8,9 - OBDD
2,3,7,8 - TBDF
1,2,3,7,8 -PeBDF
2,3,4,7,8 -PeBDF
1,2,3,4,7,8 -HxBDF
1,2,3,4,6,7,8 -HpBDF
1,2,3,4,6,7,8,9 - OBDF
Total PBDD/Fs
(ND=0; EMPC= 0)
Total PBDD/Fs
(ND=0; EMPC= EMPC)
Total PBDD/Fs
(ND=DL; EMPC= EMPC)
Sample Description - Heat flux (kW/m2)
BFR-
50
BFR-
50
BFR-
100
BFR-
100
BFR +
PHF-50
BFR +
PHF-50
ng/g
O.OOE+00
3.72E-01
1.38E-01
6.97E-02
8.76E-02
O.OOE+00
O.OOE+00
5.81E-01
8.90E-01
1.32E+00
5.68E-01
7.35E-02
3.21E+00
4.10E+00
4.14E+00
O.OOE+00
1.79E-01
9.57E-02
4.68E-02
7.73E-02
O.OOE+00
O.OOE+00
O.OOE+00
5.14E-01
6.60E-01
3.45E-01
5.57E-02
1.97E+00
1.97E+00
2.05E+00
O.OOE+00
1.85E-01
1.25E-01
5.45E-02
1.42E-01
O.OOE+00
O.OOE+00
1.59E-01
2.47E-01
2.29E-01
4.21E-01
-
1.56E+00
1.56E+00
1.89E+00
O.OOE+00
3.25E-01
1.49E-01
7.65E-02
1.18E-01
O.OOE+00
O.OOE+00
2.24E-01
4.06E-01
9.04E-01
6.25E-01
O.OOE+00
2.83E+00
2.83E+00
3.07E+00
O.OOE+00
1.20E-01
8.79E-02
4.49E-02
7.36E-02
O.OOE+00
O.OOE+00
2.42E-01
3.60E-01
4.86E-01
2.48E-01
O.OOE+00
1.66E+00
1.66E+00
2.09E+00
O.OOE+00
1.42E-01
6.94E-02
3.16E-02
7.18E-02
O.OOE+00
O.OOE+00
2.79E-01
6.11E-01
5.72E-01
3.11E-01
O.OOE+00
2.06E+00
2.09E+00
2.63E+00
The laminate samples with halogenated components (BFR-P) could not be quantitated due to significant halogenated interference.
"EMPC" indicates that the bromine isotope ratio for the two molecular ion clusters was not within ±15% of the correct isotope ratio. When the
two molecular ions are not within the correct isotope ratio, the two molecular ions are quantitated separately and the smaller quantitation is
denoted EMPC. The EMPC notation identifies that the presence of an additional molecule may be influencing the detection level of the
compounds of interest.
A-201
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PBDD/Fs Emission Factors
3.50E+00
3.00E+00
M
j£
1
2.50E+00
2.00E+00
Q
Q
CO
Q.
1.50E+00
l.OOE+00
5.00E-01 -
O.OOE+00
1,2,3,4,6,7,8,9-OBDF
1,2,3,4,6,7,8-HpBDF
1,2,3,4,7,8-HxBDF
2,3,4,7,8-PeBDF
1,2,3,7,8-PeBDF
2,3,7,8-TBDF
1,2,3,4,6,7,8,9-OBDD
1,2,3,4,6,7,8-HpBDD
1,2,3,7,8,9-HxBDD
1,2,3,4,7,8 + 1,2,3,6,7,8 - HxBDD
1,2,3,7,8-PeBDD
2,3,7,8-TBDD
"%
Sample Description
Figure 4-4. PBDD/Fs Emission Factors Plot for ND=0 and EMPC=EMPC
The laminate samples with halogenated components (BFR + P) could not be quantitated due to significant
interference.
4.6 PAH Emissions
Table 4-6, Table 4-7 and Figure 4-5 show the total PAH emission factors for the 16 EPA priority
PAHs quantified for the different printed circuit board laminates tested using the cone
calorimeter. Brominated flame retardant (BFR) laminates burned at 50 kW/m heat flux had the
highest total PAH emissions and no flame retardant (NFR) laminates burned at 50 kW/m heat
flux had the least. At a higher heat flux (100 kW/m2), the NFR sample showed 29% higher PAH
emissions than the halogen-free (HFR) sample at the same heat flux. Emissions for the BFR were
similar at both heat flux levels.
The observed trends of PAH emissions make sense in light of both the known and assumed
flame retardant mechanisms for the two types of flame retardant systems. Since the BFR is a
vapor phase flame retardant, any combustion of that flame retardant with decomposing epoxy
structures should generate more incomplete combustion products. In the case of the HFR system,
it is assumed a phosphorus-based flame retardant is present, which has more of a condensed
phase (char formation) mechanism and binds up most of the possible PAH structures on the
burned sample residue rather than created in the flame front as seen with BFRs. The results
presented in Figure 4-5 support this general trend with a wide range of PAH products detected.
The presence of component powders affected PAH emissions for both BFR and HFR systems.
PAH emissions were reduced for the 1556 HFR samples that had components compared to the
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other HFR samples. In some cases, a slight increase in PAH emissions was noted for the other
HFR laminates when components were present. For the BFR systems, the presence of
components slightly lowered total PAH emissions.
Since PAHs are known to be the nascent precursors of soot, a higher presence of PAHs should
lead to higher PM yields from combustion. In this study, the PM yields (Table 4-4 and Figure
4-3) and the PAH emissions (Table 4-6 and Figure 4-5) did not always have this positive
correlation. Typically, naphthalene yields should have been higher than the other PAHs detected.
Analysis of our methods to determine breakthrough of PAHs during sampling at these high
velocities has shown that fluorene and heavier compounds are captured using 4 PUFs in the glass
cartridge that holds the PUFs and that acenaphthylene breakthrough was almost 50%. However,
since the carcinogenic PAHs are of interest and the extraction of eight PUFs is complex, no
attempt was made to prevent breakthrough of compounds lighter than fluorene by increasing the
number of PUFs. Figure 4-6 displays the PAH emissions data excluding compounds with a lower
molecular weight than fluorene likely to have had breakthrough. The same emission trends were
observed when naphthalene, acenapthylene, and acenapthene were excluded, suggesting that no
crucial information was lost by not sampling compounds requiring eight sampling PUFs.
PAH Emission Factors
6.0E+00
5.0E+00
4.0E+00
3.0E+00
M
(/T
2.0E+00
l.OE+00
O.OE+00
I
Benzo[ghi]perylene
Dibenz[ah]anthracene
lndeno[123cd]pyrene
Benzo[a]pyrene
• Benzo[fcn-k]fluoranthene
• Chrysene
Benz[a]anthracene
• Pyrene
• Fluoranthene
• Anthracene
• Phenanthrene
• Fluorene
• Acenaphthene
• Acenaphthylene
• Naphthalene
4v
xx>.
Sample Description
Figure 4-5. PAH Emission Factors Plotted for Naphthalene and Higher Molecular Weight PAHs Detected
from the EPA List of 16* Priority PAHs
*Benzo[b]fluoranthene andbenzo[k]fluoranthene are reported together
A-203
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PAH Emission Factors (Flourene+)
2.5E+00
2.0E+00
1.5E+00
00
DL
I.OE+OO
5.0E-01
O.OE+00
1
Benzo[ghi]perylene
Dibenz[ah] anthracene
lndeno[123cd]pyrene
Benzo[a]pyrene
Benzo[fcn-k]fluoranthene
I Chrysene
Benz[a]anthracene
Pyrene
I Fluoranthene
I Anthracene
I Phenanthrene
I Fluorene
** **
Sample Description
°
J>>
Figure 4-6. PAH Emission Factors for Fluorene and Higher Molecular Weight PAHs Detected from the EPA
List of 16* Priority PAHs
*Benzo[b]fluoranthene andbenzo[k]fluoranthene are reported together
When looking solely at the release of known carcinogenic PAHs (Figure 4-7), trends similar to
those in Figure 4-5 and Figure 4-6 are observed. BFR systems produce more of the carcinogenic
PAHs than the HFR or NFR systems. The addition of components does not appear to drastically
affect the yields of carcinogenic PAHs. The presence of components decreases the yields in
some cases probably due to a dilution effect from the added mass when calculating emission
factors. The high heat flux can cause the NFR system to give off just as much carcinogenic
PAHs as a flame retardant + component system from a lower heat flux. When looking at only the
toxic equivalent emission factors of carcinogenic PAH values (Figure 4-8), it is again observed
that BFR has the highest value followed by the HFR systems and then the NFR system.
A-204
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Carcinogenic PAH Emission Factors
8.0E-01
7.0E-01 -
6.0E-01
00
">" 5.0E-01
.u 4.0E-01
c
01
00
O 3.0E-01
2.0E-01
l.OE-01
O.OE+00
I
Benzo[ghi]perylene
Dibenz[ah] anthracene
lndeno[123cd]pyrene
Benzo[a]pyrene
Benzo[fcn-k]fluoranthene
I Chrysene
Benz[a]anthracene
1
Sample Description
Figure 4-7. Emission Factors of Carcinogenic PAHs from the EPA List of 16 Priority PAHs
*Benzo[b]fluoranthene andbenzo[k]fluoranthene are reported together
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Toxic Equivalent Emission Factors of Carcinogenic PAHs
00
£
1.6E-01
1.4E-01
1.2E-01
l.OE-01
<= 8.0E-02
•| 6.0E-02
•_
(D
-------
Analyte
Dibenz[a, h] anthracene
Benzo [g, h, /'Jperylene
Total 16 EPA PAHs
Sample Description - Heat flux (kW/m2)
BFR - 50
BFR - 100
BFR + P-
50
BFR +
PHF - 50
NFR-
50*
NFR-100
Emission Factors, g/kg
2.6E-02
4.8E-02
5.22E+00
2.7E-02
3.7E-02
5.08E-K)0
2.5E-02
4.7E-02
3.93E+00
2.1E-02
2.7E-02
3.69E+00
O.OE+00
8.2E-03
6.24E-01
O.OE+00
2.7E-02
1.95E+00
*Benzo[b]fluoranthene andbenzo[k]fluoranthene are reported together
*From a single run
Table 4-7. PAH Emission Factors from EPA List of 16* Priority PAHs for HFR and 1556 HFR at 50 and 100
kW/m2
Analyte
Naphthalene
Acenaphthylene
Acenaphthene
Fluorene
Phenanthrene
Anthracene
Fluoranthene
Pyrene
Benz[a]anthracene
Chrysene
Benzo [b +&]fluoranthene
Benzo [a]pyrene
Indeno [1, 2, 3-c
-------
Although attempts were also made to determine presence of other chlorinated benzenes/phenols
known to be PCDD/Fs precursors, none were detected at the sample concentrations analyzed for
PAHs. No significant presence of chlorobenzenes and phenols detected in the laminate burns is a
likely indicator of a negligible presence of chlorinated dioxins under the conditions explored in
this study. However, the absence of PCDD/Fs cannot be conclusively stated without further
analysis of more concentrated samples or attempts to analyze extracts for PCDD/Fs disregarding
the previously discussed issues related to the absence of the chlorinated pre-sampling surrogates.
Scanning for organophosphorus was also done because it was believed that the non-halogenated
flame retardants present in the samples were phosphorus-based. The detection of
organophosphorus emissions would indicate the presence of a vapor phase flame retardant while
the detection of no organophosphorus emissions would indicate the presence of a condensed
phase flame retardant. The organophosphorous compounds detected in this study are given in
Table 4-9. As Table 4-9 shows, different compounds were detected from the repeat burn of the
same laminate. The environmental and health effects of the compounds detected are not
evaluated in this report to explain their impact. From a flame retardant perspective, some of the
compounds fit with known flame retardant chemistry while others are likely post-combustion
reaction products or reactions between the phosphorus flame retardant and parts of the circuit
board. For example, the phosphorous compounds with silicon in their chemical structure are
likely present due to reactions between organophosphorus and e-glass during burning. The
presence of any halogen-phosphorus compounds is likely due to reaction between halogen and
organophosphorus during burning. Other organophosphorus compounds present that contain
phosphonic or phosphinic acids are decomposition products of known phosphorus flame
retardants, especially compounds containing phenyl groups. However, it should be recognized
that the exact phosphorus flame retardant used in these systems was not reported to UDRI,
leaving the interpretation of the data based upon information in open literature for phosphorus
flame retardants. Combustion chemistry is complex, especially when many components are
present, and the list of compounds detected is not surprising.
A-208
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Table 4-9. Organophosphorous Compounds Detected
Laminate
Description
BFR -50
BFR -50
BFR + P-50
BFR + P -50
BFR + PHF-50
BFR + PHF-50
BFR -100
BFR -100
HFR +P-50
HFR + PHF-50
HFR + PHF-50
1556 +P -50
1556+ PHF-50
Organophosphorous Compounds Detected
1 -Ethyl- 1 -hydridotetrachlorocyclotriphosphazene
Silanol, trimethyl-, pyrophosphate
Phosphonic acid, methylenebis-, tetrakis(trimethylsilyl) ester
O,O'-(2,2'-Biphenylylene)thiophosphoric acid
Bis(4-methoxyphenyl)phosphinic acid
Silanol, trimethyl-, pyrophosphate(4:l)
l-Phosphacyclopent-2-ene, 1-methyl -5-methylene-2,3-diphenyl-
4-Phosphaspiro[2.4]hept-5-ene, 4-methyl-5,6-diphenyl-
Bis(4-methoxyphenyl)phosphinic acid
l-Phosphacyclopent-2-ene, 1-methyl -5-methylene-2,3-diphenyl-
Ethylphosphonic acid, bis(tert-butyldimethylsilyl) ester
Methylenebis(phosphonic acid), tetrakis(3-hexenyl) ester
Phosphonic acid, phenyl-, diethyl ester
(2-Bromo-3 -methylphenyl) diphenylphosphine
Phosphine imide, P,P,P-triphenyl-
Phosphorane, 1 lH-benzo[a]fluoren-l-ylidenetriphenyl-
l-Phosphacyclopent-2-ene, 1-methyl -5-methylene-2,3-diphenyl-
Phosphine imide, P,P,P-triphenyl-
Area
%
0.04
0.51
0.17
0.38
0.1
0.08
0.61
0.15
0.15
0.23
8.33
0.29
0.25
0.34
0.3
0.43
0.53
0.21
4.7 Heat Release (Flammability) Results
The flammability data for the laminate samples and laminates + component powders are shown
in Appendix A. Since material flammability/fire safety was not the primary focus of this study, it
is not a primary focus of the Results and Discussion section. Instead, suggestions are provided on
how the heat release results should and should not be interpreted and used.
The circuit board samples in this report are likely formulated to pass a small flame test, such as
UL-94 V-0/-1/-2 (ASTM D3801), or a glow wire test (ASTM D6194) that mimics a short circuit
ignition scenario. The cone calorimeter used in this report represents a well-ventilated fire
scenario when it is run at a flow of 24 L/s as per the ASTM E1354 method. It better represents a
larger fire source and not the small ignition source typically seen in electronic circuit boards. In
this report, the cone calorimeter experiments were run at a lower flow rate of 15 L/s, which
would roughly simulate open burn type conditions, not an intense well ventilated fire. Further,
where ASTM D3801 uses a small flame source, the cone calorimeter uses a radiant heater, which
r\
in this case was set to heat fluxes of 50 and 100 kW/m and represent a medium sized and a very
large scale fire, respectively. The measurement of heat release from materials that were not
designed to protect against robust heat sources like that of the cone calorimeter is a limitation of
this study. It should not be used to infer the fire safety of the products in their respective
scenarios. Each fire test used for regulating flame retardant materials is tailored for a specific fire
risk scenario; the standards are not interchangeable. Therefore, the cone calorimeter data in this
A-209
-------
study is best used to understand how much heat an object gives off when burned in a situation
where it is well ventilated and a robust heat source is present. With this in mind, heat release rate
and smoke data from the cone calorimeter testing of circuit boards can be used to better
understand:
r\
• Heat output from the burning material when properly disposed of (100 kW/m heat flux
conditions) to know if the laminate gives off enough heat to run the incinerator cleanly.
• Heat output if e-waste was to be used for waste-to-energy processes (how much energy
would be generated by the burning of e-waste).
• Relative rankings on flame retardant performance outside the regulatory test scenario for
which it was designed. Specifically, cone calorimeter measures can inform how the materials
would contribute to a larger fire event (server room fire, house fire) when set afire by another
object in the same room. The lower the heat release of the material, the less likely it will
contribute negatively to a large fire event, or, spread fire should it be exposed to heat and
flame.
While the cone calorimeter data can be useful, care should be taken when using it for the
selection of fire safe materials, or in the case of this report, figuring out which flame retardant
chemistry (brominated or non-halogenated) is appropriate for a particular need. Cone calorimeter
data can guide selections, but each material scientist and engineer will need to look closely at the
fire standards to decide what aspect of fire performance certain materials must meet.
Although cone calorimeter measurements can give insight into heat output and comparative
flame retardant performance, there are conclusions that cannot be made with the
flammability/heat release data in this report:
• The measured heat release of each of the system does not infer that any one material is safer
than another from a fire safety perspective. Since the cone calorimeter measures flammability
in a different way than other regulatory tests, a low heat release in the cone calorimeter does
not ensure a "pass" result in a regulatory test. A lower peak HRR would mean that the
burning laminate would be less likely to ignite other nearby objects though. A lower total
HR would indicate that if the burning laminate was fully burned, it would contribute less
total heat (fuel) to the overall fire.
• Smoke release in the cone calorimeter is very much a function of the combustion conditions
used in the test. Smoke release may be more intense or less intense under different ventilation
conditions and the results cannot be used to infer that a particular material will be better or
worse than another in a different flaming combustion configuration/scenario. Smoke release
in the cone calorimeter is very different than smoke release from a full high heat flux fire and
is also very different than smoke release from a small flame ignition source.
• Cone calorimeter data has a known % error of ±10%.
With the above caveats in mind, the following trends are observed in Table 4-10 and Table 4-11:
r\
• At a heat flux of 50 kW/m , the flame retardant systems show lower peak heat release when
compared to the non-flame retardant systems. The non-halogenated "1556 HFR" sample
shows the lowest flammability overall but also has a lower amount of total mass lost,
suggesting that it either has more non-combustible mass present or is a more robust char
forming flame retardant system.
A-210
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• The addition of component powders generally increased total heat release and had mixed
effects on peak HRR.
• At a heat flux of 100 kW/m2, only the brominated flame retardant continues to lower heat
release (peak HRR and total HR) versus the non-flame retardant control. The non-
halogenated system gives heat release roughly equal to, or slightly higher, than the non-flame
retardant system.
Table 4-10. Heat Release Summary for Laminates and Laminates + Component Powders Tested at 50 kW/m2
Sample
Description -
Heat Flux (50
kW/m2)
BFR-1
BFR-2
BFR-3
BFR + P-1
BFR + P -2
BFR + P -3
BFR + PHF-1
BFR + PHF -2
BFR + PHF -3
NFR-1
NFR-2
NFR-3
HFR-1
HFR-2
HFR-3
HFR + P-1
HFR + P -2
HFR + P- 3
HFR+ PHF -1
HFR + PHF -2
HFR + PHF -3
1556 HFR -1
1556 HFR -2
1556 HFR -3
1556 HFR + P-1
1556 HFR + P-2
1556 HFR + P-3
1556 HFR +PHF-1
1556 HFR + PHF-2
1556HFR+PHF-3
Sample
Thickness
(mm)
0.49
0.49
0.50
0.49
0.48
0.49
0.48
0.48
0.48
0.43
0.41
0.44
0.57
0.56
0.58
0.56
0.58
0.58
0.58
0.57
0.56
0.46
0.45
0.46
0.46
0.46
0.45
0.45
0.46
0.46
Time to
ignition
(s)
11
10
10
9
8
14
12
18
14
11
11
12
12
15
17
10
8
14
21
31
26
14
24
16
12
9
9
18
22
22
Peak
HRR
(kW/m2)
279.0
272.4
296.5
280.2
265.0
255.7
279.3
331.4
266.8
406.1
391.6
445.9
406.7
292.1
368.5
267.4
278.9
303.5
343.0
294.0
271.1
181.2
205.9
230.9
165.7
185.9
165.8
196.7
209.4
220.6
Average
HRR
(kW/m2)
65.31
64.23
91.31
81.29
79.41
79.94
83.44
88.70
81.37
77.77
87.52
88.69
98.15
84.51
94.59
88.64
102.55
102.61
111.98
96.43
86.55
55.56
50.88
63.06
73.22
68.54
71.18
76.26
83.15
81.50
Weight
% Lost
(%)
37.2
39.8
37.5
29.3
28.8
27.9
25.2
25.1
24.9
32.3
28.4
34.9
35.8
32.3
34.2
25.0
25.9
25.6
25.1
21.5
22.5
27.2
23.0
25.3
23.3
20.9
22.8
20.0
20.4
20.5
Total
Heat
Release
(MJ/m2)
4.4
4.8
4.8
6.9
6.9
6.6
6.8
6.9
6.9
5.8
6.1
6.5
7.8
6.7
7.3
8.2
9.6
9.2
9.8
7.8
8.0
4.2
3.6
4.6
6.6
6.1
6.6
6.4
7.1
6.5
Total
smoke
Release
(m2/m2)
485.2
496.9
455.2
719.9
698.5
657.0
467.1
446.5
490.8
228.3
199.0
238.8
240.2
237.5
274.7
451.2
461.4
403.0
330.9
372.5
356.9
270.5
232.1
236.4
400.4
382.6
409.3
293.6
324.0
310.1
MARHE
(kW/m2)
115.6
114.2
146.8
127.7
116.3
105.9
111.7
107.5
108.4
130.0
139.4
140.8
141.4
106.9
124.7
116.1
139.8
128.4
128.4
92.4
98.5
76.0
60.7
84.1
93.1
92.3
92.2
88.3
88.6
84.4
A-211
-------
Table 4-11. Heat Release Summary for Laminates and Laminates + Component Powders Tested at 100
kW/m2
Sample
Description -
Heat Flux
(100 kW/m2)
BFR-1
BFR-2
BFR-3
NFR-1
NFR-2
NFR-3
HFR-1
HFR-2
HFR-3
Sample
Thickness
(mm)
0.41
0.42
0.40
0.32
0.35
0.34
0.49
0.48
0.49
Time to
ignition
(s)
3
5
3
3
4
4
6
6
5
Peak
HRR
(kW/m2)
226.7
390.6
356.8
356.4
490.5
387.5
494.7
495.2
367.1
Average
HRR
(kW/m2)
55.5
80.4
77.0
79.7
94.5
70.8
104.0
104.9
120.0
Weight
% Lost
(%)
41.1
45.8
45.3
36.5
38.9
37.5
38.6
35.8
40.5
Total
Heat
Release
(MJ/m2)
4.5
5.7
5.4
5.3
6.6
5.0
7.4
7.5
10.2
Total
smoke
Release
(m2/m2)
475.6
451.0
392.7
194.6
230.1
219.5
231.4
237.5
325.6
MARHE
(kW/m2)
128.5
180.2
189.4
188.4
201.3
152.5
205.4
215.9
200.5
5 Conclusions
While the cone calorimeter is a useful instrument for measuring flammability from a fire safety
perspective, the use of the cone calorimeter in this study was as a combustion science tool. Heat
fluxes plus a lower flow rate were chosen to represent potential open burn (50 kW/m2) and
incineration for metal recovery (100 kW/m2). The following general trends were observed:
50kW/m2heatflux:
• BFR: PBDD/Fs emitted. PAHs emitted at higher levels compared to other samples.
• HFR: PAHs emitted at higher levels than NFR sample.
• NFR: PAHs emitted at lowest levels compared to other samples.
100 kW/m2 heat flux:
• BFR: PBDD/Fs emitted. PAHs emitted at higher levels compared to other samples.
• HFR: PAHs emitted at lowest levels compared to other samples.
• NFR: PAHs emitted at a level slightly lower than the BFR sample.
Effect of components on emissions:
• PBDD/Fs: PBDD/Fs were similar or lower than sample without components.
• PAHs: In general, presence of components reduced PAH emissions for BFR, were similar or
slightly highly for HFR and were lower for 1556 HFR. The size of these differences varied
depending on which PAHs were summarized (see section 4.6).
• PAH emissions and smoke release of laminates with low halogen components were slightly
lower than standard components across all three difference laminates.
Smoke, PM, CO and CO2 release:
• Smoke release was higher for BFR than HFR laminates. Smoke release was higher with
components due to greater amount of material. PM generally had small differences between
samples. There were negligible differences in CO release between samples. CO2 release was
A-212
-------
lowest for BFR but with small differences between samples. Results are complex and
smoke/PM results do not always correlate.
The results of this report do not suggest that any one material is safer than another in regards to
fire safety. The results do show that the flame retardants lower heat release under flaming
combustion even at high heat fluxes.
Overall, the results clearly show that all of the samples generated combustion by-products other
than CC>2 and water. The flame retardant samples in some cases generated more pollutants than
the NFR samples, as one would expect since the flame retardants are inhibiting combustion. Any
system that slows down flaming combustion will generate higher levels of smoke, CO, PM, and
other incomplete combustion products. A flame retardant with a vapor phase mechanism (such as
BFR) will generate more species than a flame retardant that uses a condensed phase mechanism
(assumed to be the case of the phosphorus-based FIFR system). It is important to look at flame
retardant chemistry, flame retardant mechanism, polymer decomposition chemistry, and fire
scenario (heat, ventilation) to determine what sorts of species may be formed during accidental
fires (where flame retardants serve as passive protection) or intentional ones (proper and
improper incineration).
The other major finding of this report is that the cone calorimeter was able to obtain a diverse
amount of information about emissions from circuit boards. For the brominated laminate with
halogenated components, the complexity of the emissions made them difficult to separate and
identify but the results show that pollutants exist. Further work and separation science would be
needed to achieve that higher level of data resolution with these particular samples.
Based upon the results in this report, users of flame retardants for circuit boards should realize
that if PCBs or other e-waste is to be incinerated for precious metal recovery, it should be done
properly with good incinerator control to address the pollutant emissions that will occur. Even
non-flame retardant boards when incinerated improperly will release pollutants of concern, as
was seen from the data in this report. Emissions may have been lower, but they were still present.
The use of flame retardants is a technology compromise: it provides fire safety performance
(thus lowering risk of short circuit ignitions in daily use) but will generate higher pollutants
when incinerated improperly. Other environmental concerns may drive the selection of different
flame retardant chemistry, but from emissions alone, such a decision cannot be made. With
careful attention to polymer thermal decomposition chemistry and combustion science, it may be
possible to generate a flame retardant in the future which provides fire protection and minimizes
emissions/pollutants of concern during burning. If there is a desire to develop clean burning
flame retardant materials, entirely different flame retardant chemistries must be developed.
Otherwise, the safest solution to this problem is to recover precious metals via well controlled
incineration with regulatory emissions controls in place as well as cost-effective methods of e-
waste collection and disposal.
6 Acknowledgments
The authors wish to thank Kathleen Beljan, Mary Galaska, and Kathy Schenck of UDRI for their
assistance with the cone calorimeter tests and Anne Chauvian and Saikumar Chalivendra for
their initial support for the modified experimental design work. Barbara Wyrzvkowska-Ceradini
A-213
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and Craig Williams assisted with sample extraction, clean-up and analysis at EPA labs. Funding
and materials for the project were provided by Albemarle, Boliden, BSEF, Chemtura, Clariant,
Ciba Specialty Chemicals, Dell, Fujitsu-Siemens, Hewlett-Packard, IBM, ICL-IP America Inc.,
Intel, Isola, ITEQ, Matsushita Electric Industrial and Matsushita Electric Works, Nabeltec,
Panasonic, Seagate, Sony, Supresta, & U.S. EPA.
A-214
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7 Appendix A: Circuit Board Flammability Data
Along with emissions data, heat release information as per ASTM E1354 was also collected.
This data is reported in below as a function of heat flux and samples tested. Observed fire
behavior, final chars, and heat release rate curves are given. The data is presented for the
purposes of completeness in this report. It does not infer any particular level of fire safety about
the samples tested. Merely it shows what the measured heat release information was from these
samples when tested at 15 L/sec exhaust flow in triplicate as per the ASTM methodology.
In the section below, BFR indicates a brominated flame retardant system being tested, while HF
indicates halogen-free flame retardant and NFR indicates that the sample had no flame retardant
present. Component blends are identified as "Comp", meaning a component blend where
halogen was present in the component blend powder, and as "HF Comp" meaning the mostly
halogen-free component blend was used.
A-215
-------
Heat Release Rate-50 kW/m
Table 7-1. Heat Release Rate Data (50 kW/m2)
Sample
Description -
Heat Flux
(50 kW/m2)
BFR-1
BFR-2
BFR-3
BFR + P-1
BFR + P-2
BFR + P -3
BFR + PHF -1
BFR + PHF -2
BFR + PHF -3
NFR-1
NFR-2
NFR-3
HFR-1
HFR-2
HFR-3
HFR + P-1
HFR + P-2
HFR + P-3
HFR+PHF-1
HFR + PHF -2
HFR + PHF -3
1556 HFR -1
1556 HFR -2
1556 HFR -3
Sample
Thickness
(mm)
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.4
0.4
0.4
0.6
0.6
0.6
0.6
0.6
0.6
0.6
0.6
0.6
0.5
0.5
0.5
Time to
ignition
(s)
11
10
10
9
8
14
12
18
14
11
11
12
12
15
17
10
8
14
21
31
26
14
24
16
Peak
HRR
(kW/m2)
279
272
296
280
265
256
279
331
267
406
392
446
407
292
368
267
279
304
343
294
271
181
206
231
Time to
Peak
HRR
(s)
20
20
25
30
35
34
33
37
32
28
26
29
31
39
36
45
39
41
49
47
43
32
38
30
Average
HRR
(kW/m2)
65
64
91
81
79
80
83
89
81
78
88
89
98
85
95
89
103
103
112
96
87
56
51
63
Starting
Mass
(S)
10.5
10.8
10.4
20.5
20.5
20.4
20.3
20.3
20.5
9.3
9.1
9.5
11.4
11.5
11.4
21.2
21.6
21.5
21.5
21.4
21.3
10.7
10.5
10.7
Total
Mass
Loss
(S)
3.9
4.3
3.9
6.0
5.9
5.7
5.1
5.1
5.1
3.0
2.6
3.3
4.1
3.7
3.9
5.3
5.6
5.5
5.4
4.6
4.8
2.9
2.4
2.7
Weight %
Lost
(%)
37.2
39.8
37.5
29.3
28.8
27.9
25.2
25.1
24.9
32.3
28.4
34.9
35.8
32.3
34.2
25.0
25.9
25.6
25.1
21.5
22.5
27.2
23.0
25.3
Total
Heat
Release
(MJ/m2)
4.4
4.8
4.8
6.9
6.9
6.6
6.8
6.9
6.9
5.8
6.1
6.5
7.8
6.7
7.3
8.2
9.6
9.2
9.8
7.8
8.0
4.2
3.6
4.6
Total
smoke
Release
(m2/m2)
485
497
455
720
699
657
467
447
491
228
199
239
240
238
275
451
461
403
331
373
357
271
232
236
Avg. Effective
Heat of Comb.
(MJ/kg)
15.14
11.21
17.58
11.92
11.71
11.50
13.09
13.39
13.14
18.66
22.87
19.36
19.00
17.75
18.44
15.36
17.01
16.50
17.90
16.67
16.38
14.16
14.61
16.38
MARHE
(kW/m2)
116
114
147
128
116
106
112
108
108
130
139
141
141
107
125
116
140
128
128
92
99
76
61
84
FIGRA
13.95
13.62
11.86
9.34
7.57
7.52
8.46
8.96
8.34
14.50
15.06
15.37
13.12
7.49
10.24
5.94
7.15
7.40
7.00
6.26
6.30
5.66
5.42
7.70
A-216
-------
Sample
Description -
Heat Flux
(50 kW/m2)
1556 HFR + P -1
1556 HFR + P-2
1556 HFR + P-3
1556 HFR +PHF -1
1556 HFR + PHF-2
1556 HFR +PHF -3
Sample
Thickness
(mm)
0.5
0.5
0.5
0.5
0.5
0.5
Time to
ignition
(s)
12
9
9
18
22
22
Peak
HRR
(kW/m2)
166
186
166
197
209
221
lime to
Peak
HRR
(s)
49
34
45
34
39
44
Average
HRR
(kW/m2)
73
69
71
76
83
82
Starting
Mass
(S)
20.6
20.6
20.6
20.0
20.6
20.5
Total
Mass
Loss
(S)
4.8
4.3
4.7
4.0
4.2
4.2
Weight %
Lost
(%)
23.3
20.9
22.8
20.0
20.4
20.5
Total
Heat
Release
(MJ/m2)
6.6
6.1
6.6
6.4
7.1
6.5
Total
smoke
Release
(m2/m2)
400
383
409
294
324
310
Avg. Effective
Heat of Comb.
(MJ/kg)
13.56
13.99
13.86
15.73
16.49
15.31
MARHE
(kW/m2)
93
92
92
88
89
84
FIGRA
3.38
5.47
3.69
5.79
5.37
5.01
A-217
-------
BFR Fire Behavior
Upon exposure to the cone heater, the sample began to smoke and make crackling sounds
very quickly. It then burst into flame with orange, blue, and purple colors noted. The sample was
noted to curl up some during burning with the 2n sample curling and delaminating to a severe
degree such that the cone heater shutters could not close at the end of the experiments. Heat
release was reproducible (Figure 7-1) and the final chars (Figure 7-2) were blackened with
copper plates noted. The sample where the shutters could not be closed is shown on the far left of
Figure 7-2 where the surface char has be slowly burned away leaving behind just copper and
fiberglass. So with sufficient heat and oxygen, eventually most of the carbon can be burned
away/ consumed.
BFR HRR
300
250 -
200
150 -
100
40 60
Time (s)
80
100
Figure 7-1. HRR for BFR Sample
Figure 7-2. Final Chars for BFR Sample
BFR + P (populated halogen components)Fire Behavior
Fire behavior of this sample was the same as the BFR sample, but the flame colors were
more muted. The component powder was also noted to spit and pop a bit, with occasional pieces
of the powder leaving the aluminum foil holder. Heat release rates (Figure 7-3) were
reproducible indicating that the powder did not inhibit burning behavior. Final chars (Figure 7-4)
were black with yellowish-black powder on top.
A-218
-------
BFR+P HRR
300
250
200
£ 150
X
te
100
50
0 20 40 60 80 100
Time (s)
Figure 7-3. HRR for BFR + P Sample
120
Figure 7-4. Final Chars for BFR + P Sample
BFR + PHF(Populated halogen-free components)Fire Behavior
Upon exposure to the heater, the sample smoked and crackled, and then ignited on one
side of the sample with the flames sweeping across the surface quickly. Flames were noted to be
blue and purple in color, and the component powder had a tendency to crackle and bubble,
suggesting the presence of thermoplastic material in the HF powder. FIRR was fairly
reproducible (Figure 7-5) although the 2nd sample (HRR-2) has a higher peak HRR and delayed
time to ignition when compared to the other two samples. Final chars (Figure 7-5) were black
with copper squares noted. From this observation the halogen-containing component powder
does not flow (Figure 7-4) and may contain less thermoplastic material as opposed to the
halogen-free component powder which appears to burn up more completely and leave less of a
powdery residue.
A-219
-------
BFR + PHFHRR
350
300 -
0 20 40 60 80 100 120
Time (s)
Figure 7-5. HRR for BFR + PHF Sample
Figure 7-6. Final Chars for BFR + PHF Sample
NFR Fire Behavior
Upon exposure the cone heater, the sample made a lot of crackling noises, and then began
to smoke before quickly igniting. The sample curled quite a bit during burning such that the
shutters could not be closed at the end of the experiment. Heat release (Figure 7-7) was very
reproducible and the final chars (Figure 7-8) show just the copper and fiberglass as most of the
residual carbon was burned away since the shutters would not close. Therefore any char which
had self-extinguished during the test was slowly pyrolyzed away until the sample could be
removed from the cone calorimeter.
A-220
-------
NFRHRR
500
400
. 300
OL
200
100
0 h
20 40 60 80 100 120
Time (s)
Figure 7-7. HRR for NFR Sample
Figure 7-8. Final Chars for NFR Sample
HFR Fire Behavior
Upon exposure to the cone heater, the sample began to crackle and then smoke, followed
by ignition. The sample burned with some white colors, suggesting the presence of a
phosphorus-based flame retardant. The first sample curled during the test and the shutters could
not be closed. Some scatter in the HRR was noted (Figure 7-9), especially in the peak HRR
values. Final chars (Figure 7-10) in general show black-grey chars on the surface of the
fiberglass, but some char is noted on the copper squares as well.
A-221
-------
HFRHRR
500
Time (s)
Figure 7-9. HRR for HFR Sample
Figure 7-10. Final Chars for HFR Sample
HFR+ P (Comp) Fire Behavior
Upon exposure to the cone heater, the sample began to smoke right away, followed an
ignition and some loud crackling noises. Some parts of the powder also spat out of sample
surface during this burning behavior with some flames going out sideways from under the
powder. Some blue flames were noted at the beginning and end of the test. The third sample
tested had some curling and the shutters could not be closed at the end of the test. Heat release
(Figure 7-11) showed some scatter in the peak HRR values, but the scatter was not severe. Final
chars (Figure 7-12) were completely black and the powder is of a similar color, unlike the BFR
sample above which had the same component powder but the powder char was of a different
color at the end of the test (Figure 7-4). The curling observed for the 3rd sample can be seen in
the middle of Figure 7-12.
A-222
-------
HFR + PHRR
350
300
Time (s)
Figure 7-11. HRR for HFR + P Sample
Figure 7-12. Final Chars for HFR + P Sample
HFR + PHFFire Behavior
Fire behavior for this sample was similar to that of the sample above, except no blue
colors were noted. All of the samples had a tendency to curl such that it was difficult to close the
shutters at the end of the test. Loud crackling and popping was heard, but no bubbling seen this
time as was observed for the BFR + PFIF sample. FIRR showed some scatter in the time to
ignition and peak FIRR values (Figure 7-13). Final chars (Figure 7-14) showed intact charred
powder, but with more residual color noted. Some of the copper squares can be seen under the
charred component powder.
A-223
-------
HFR + PHF HRR
350
300 -
Time (s)
Figure 7-13. HRR for HFR + PHF Sample
Figure 7-14. Final Chars for HFR + PHF Sample
1556 HFR Fire Behavior
Upon exposure to the cone heater, the sample was heard to crackle and pop, then smoke,
then ignite. The sample had small flames which were not as sooty as those seen in previous
samples. The sample also curled during burning, but flaked apart as it burned, suggesting the
presence of a phenolic resin, or some sort of charring polymer. HRR (Figure 7-15) was not very
reproducible for this sample, with notable variability in the peak HRR and time to peak HRR
behavior. Final chars (Figure 7-16) are black and grey with regions of soot on the surface. Some
of the copper squares have moved suggested they debonded from the surface during burning.
A-224
-------
1556HFRHRR
250
Figure 7-15. HRR for 1556 HFR Sample
I
Figure 7-16. Final Chars for 1556 HFR Sample
1556 HFR+ P Fire Behavior
Fire behavior for this sample was similar to that of sample 1556 HFR, but some blue
flames were noted as well. No real curling of the sample occurred when the powder was present,
but some spitting of the component powder out of the sample holder was noted. HRR (Figure
7-16) was fairly reproducible, with only the 2n sample (HRR-2) showing variability in the peak
HRR and time to peak HRR. Final chars (Figure 7-17) were black underneath with copper
squares and the powder was a dark yellow-green in color.
A-225
-------
1556 HFR+ PHRR
200
£ 100
o:
o:
Time (s)
Figure 7-17. HRR for 1556 HFR + P Sample
Figure 7-18. Final Char for 1556 HFR + P Sample
1556HFR+ PHFFire Behavior
Fire behavior for this sample was also similar to that of sample 1556 HFR, that some
colors were seen in the flames toward the end of the test with some blue and blue/green colors
noted. FIRR (Figure 7-19) was reproducible and the final chars (Figure 7-20) were black and
grey with the powder being mostly intact.
A-226
-------
1556 HFR + PHF HRR
250
Time (s)
Figure 7-19. HRR for 1556 HFR + PHF Sample
Figure 7-20. Final Chars for 1556 HFR + PHF Sample
A-227
-------
Heat Flux-100 kW/m2
Table 7-2. Heat Release Data (100 kW/m2)
Sample
Description
- Heat Flux
(50 kW/m2)
BFR-1
BFR-2
BFR-3
NFR-1
NFR-2
NFR-3
HFR-1
HFR-2
HFR-3
Sample
Thickness
(mm)
0.4
0.4
0.4
0.3
0.4
0.3
0.5
0.5
0.5
Time
to
ignition
(s)
3
5
3
3
4
4
6
6
5
Peak
HRR
(kW/m2)
227
391
357
356
490
387
495
495
367
Time
to
Peak
HRR
(s)
15
15
15
15
15
15
20
20
25
Average
HRR
(kW/m2)
56
80
77
80
94
71
104
105
120
Starting
Mass
(S)
10.2
10.7
10.4
8.8
9.5
8.8
10.9
11.2
14.1
Total
Mass
Loss
(K)
4.2
4.9
4.7
3.2
3.7
3.3
4.2
4.0
5.7
Weight
%
Lost
(%)
41.1
45.8
45.3
36.5
38.9
37.5
38.6
35.8
40.5
Total
Heat
Release
(MJ/m2)
4.5
5.7
5.4
5.3
6.6
5.0
7.4
7.5
10.2
Total
smoke
Release
(m2/m2)
476
451
393
195
230
220
231
238
326
Avg.
Effective
Heat of
Comb.
(MJ/kg)
11.05
11.58
11.72
17.75
18.37
15.91
18.49
20.75
17.95
MARHE
(kW/m2)
129
180
189
188
201
153
205
216
201
FIGRA
15.11
26.04
23.79
23.76
32.70
25.83
24.74
24.76
14.68
A-228
-------
BFR Fire Behavior
Upon exposure to the cone heater, the sample quickly began to smoke and crackle, and
then ignited quickly. The flames were noted to be orange and blue in color. With some of the
samples, smoke would shoot out the sides of the sample and escape the cone calorimeter exhaust
ducting. Some of the samples also curled/deformed during testing. Heat release (Figure 7-21)
showed some notable scatter in the peak HRR value for the 1st sample (HRR-1). The reasons for
this scatter with the 1st sample are not clear at this time, but perhaps this sample had slightly less
flammable epoxy mass than the other two samples tested. Final chars (Figure 7-22) were dark
grey with exposed glass fiber and burned/damaged copper metal squares.
BFR100KWHRR
20 40
60 80
Time (s)
Figure 7-21. HRR for BFR Sample
100 120 140
Figure 7-22. Final Chars for BFR Sample
NFR Fire Behavior
Fire behavior was identical to that of the BFR sample, except no blue colors in the flames
were noted, the appeared to be more charring and soot generated during burning, and more
curling/deformation was noted during burning. HRR was fairly reproducible (Figure 7-23) and
the final chars (Figure 7-24) were blackened over most of the surface, including the copper metal
squares.
A-229
-------
NFR 100 kW HRR
500
40
100 120
60 80
Time (s)
Figure 7-23. HRR for NFR Sample
140
Figure 7-24. Final Chars for NFR Sample
HFR Fire Behavior
Upon exposure to the heater, the sample began to smoke and crackle, with more of a
whiter smoke noted prior to ignition. Some deformation during burning was noted, and the
sample was noted to have a distinct smell to it when removed from the cone heater. HRR was
reproducible for the 1st two samples (HRR-1, HRR-2), but the third sample (HRR-3) shows a
lower peak HRR and a bit of delay in time to peak HRR (Figure 7-25). Again, reasons for this
difference are unclear at this time. Since some of the samples deformed greatly during testing, it
was not possible to close the cone heater shutters at the end of the test and so the samples were
exposed to additional heat at the end of the test after extinguishment which burned off additional
surface char, yielding light grey specimens of bare glass fiber (Figure 7-26). One of the samples
A-230
-------
did not deform as much and the shutters could be closed, giving a specimen with more surface
char (middle of Figure 7-26).
tc
cc
500
400
300
200
100
HF 100 kW HRR
20
80
40 60
Time (s)
Figure 7-25. HRR for HFR Sample
100
Figure 7-26. Final Chars for HFR Sample
A-231
-------
Heat Release Rate
500
Time to ignition (s) Time to Peak HRR
Peak HRR (kW/m2)
Figure 7-27. Heat Release Rate Plot
Overall Remarks on 50 kW/m2 Heat Flux Sample Burning Behavior:
There are notable interactions between the component powder and the polymer
decomposition chemistry going on as these samples burn. Brominated FR epoxy reacts
differently with halogen-containing and halogen-free component powder, as does the halogen-
free epoxy. The 1556 HFR sample also shows some differences when exposed to the two
different powders, but not to as great a degree seen with the BFR and HF epoxy samples. The
behavior of the FTP comp powder is worth noting on here since in one case it showed bubbling
but not in others. This may be due to a unique flame retardant reaction in the presence of
brominated epoxy, but no obvious reason for this behavior can be given at this time.
The BFR samples, as expected, gave off lots of smoke and pyrolyzed some of the copper
away in the form of copper halides, which were seen in the flames as blue colors. The FTP
samples showed some white colors indicating phosphorus release, but no blues until halogen-
containing component powder was added, suggesting that less copper was pyrolyzed during
burning. The 1556 FtFR samples showed color in the presence of the halogenated powder, and
surprisingly in the presence of the FtF component powder as well, indicating the components
again have an effect on metal pyrolysis/thermal reaction behavior.
Overall Remarks on Burning Behavior 100 kW/m2 Heat Flux:
At 100 kW/m2 heat flux, the differences in fire behavior between the samples tested were
minimal, but there were some differences noted in physical burning behavior which correlate to
A-232
-------
9
the fire behavior noted at 50 kW/m heat flux. The brominated FR epoxy does give off more
smoke and does inhibit combustion as expected, and the blue colors noted during burning are
visual evidence of bromine reacting with copper under burning/pyrolysis conditions. The non-FR
sample burns quickly and rapidly (as a sample with no flame retardant should), and the non-
halogenated FR sample also shows physical fire behavior similar to that of the non-FR sample.
The non-halogenated FR has an equally high effective heat of combustion to that of the non-FR
sample which may just suggest that the flame retardant mechanism for this material has little
effect at very high heat fluxes, or at least does not inhibit combustion as much at very high heat
fluxes. Smoke release is slightly higher though, and so the non-halogenated FR sample is having
some effect on combustion products even if no change in measured heat of combustion is
observed.
A-233
-------
8 Appendix B: Experimental Conditions
Table 8-1. Ambient Conditions during Cone Testing
Experiment
#
E2
E4
E6
E8
E10
E30
E12
E13
E15
E16
E18
E19
E21
E22
E24
E25
E27
E28
E32
E33
E35
E36
E38
E39
E41
E42
Laminate
Description-Heat
Flux-kW/m2
BFR - 50
BFR - 50
BFR + P - 50
BFR + P - 50
BFR + PHF - 50
BFR + PHF- 50
NFR -100
NFR -100
BFR -100
BFR -100
HFR -100
HFR -100
NFR -50
NFR -50
HFR - 50
HFR - 50
1556 HFR - 50
1556 HFR - 50
HFR + P - 50
HFR + P - 50
HFR + PHF - 50
HFR + PHF - 50
1556HFR + P-50
1556HFR + P-50
1556 HFR + PHF -50
1556 HFR + PHF -50
Ambient Conditions
Temperature
°C
24
22.5
22.5
23
23
22.5
22.5
24
23
22.5
22.5
22.5
22.5
22.5
23
23
22
22
22
21.5
21.5
21.5
22
21.5
21.5
20.5
Relative
Humidity
%
22
46
32
36
43
37
45
47
43
38
44
42
38
41
37
27
37
40
35
28
26
32
32
33
24
35
Pressure
mbar
998
974
969
980
980
978
981
982
975
987
986
986
987
982
985
996
986
980
995
991
981
992
981
981
998
990
Cone Set
Temperature
°C
731
721
721
721
721
725
978
978
937
927
924
922
740
736
736
736
727
725
722
722
721
721
721
721
719
719
A-234
-------
9 Appendix C: Elemental Analyses of Component Mixtures
Table 9-1. Elemental Analyses of Component Mixtures
1,4-BENZENEDICARBOXYLICACID, POLYMER WITH [1,1'-BIPHENYL]-4,4'-DIOL,
4-HYDROXYBENZOIC ACID, 6-HYDROXY-2-NAPHTHALENECARBOXYLIC ACID AND N-(4-HYDROXYPHENYL)ACETAMIDE (9CI)
1,4-BIS(2,3-EPOXYPROPOXY)BUTANE
ACRYLIC RESIN
AG (Silver)
AL (Aluminum)
AL2O3 (Aluminum oxide)
ANTIMONY TRIOXIDE
ARALDITE GY 250
AU (Gold)
B (Boron)
BARIUM TITANATE(IV)
BASIC DUROMER: POLYURETHANE RESIN (COMPOUND OF A POLYMERIC NETWORK)
BERYLLIUM
BROMINE
C.I. PIGMENT BLACK 28
CALCIUM
CALCIUM MONOXIDE
CALCIUM-CARBONATE
CARBON BLACK
CHLORINE
CHROMIUM
CHROMIUM(III)OXIDE
COBALT, ELEMENTAL
COPPER (METALLIC)
COPPER OXIDE (CUO)
CRISTOBALITE
DIIRON-TRIOXIDE
DODECANE
DUMMY SUBSTANCE
Epoxy Resin
FE (Iron)
FIBROUS-GLASS-WOOL
FLOWERS OF ZINC (Zinc Oxide)
FORMALDEHYDE, OLIGOMERIC REACTION PRODUCTS WITH 1-CHLORO-2.3-EPOXYPROPANE AND PHENOL
FRITS, CHEMICALS
FUSED SILICA
IN (Indium)
LEAD
LEAD (II) OXIDE
LEAD (II) TITANATE
MAGNESIUM TITANIUM OXIDE (MGTIO3)
MAGNESIUM-OXIDE
MANGANESE
MO (Molybdenum)
NICKEL
NICKEL OXIDE
P (Phosphorous)
PALLADIUM
P-F-R-2
Polyphenylene Sulfide
SI (Silica)
SILICA
SILICONE
SN (Stannum/Tin)
SOLVENT NAPHTHA (PETROLEUM), HEAVY AROM.
STABILIZATION UV, LIGHT, HEAT
TUNGSTEN (W)
ZINC POWDER - ZINC DUST (NOT STABILIZED)
Low Halogen: Total Non-Low Halogen:
Mass(g) per 3052.25 Total Mass(g) per
g of mixture 3052.25 g of mixture
845.140
845.140
0.002
0.135
8.208
0.004
41.150
0.000
1.721
7.065
0.000
453.479
1.082
0.000
0.086
0.281
0.000
0.157
1.866
12.662
0.086
0.001
0.355
0.615
425.069
9.852
1.174
121.742
0.014
0.002
33.936
8.160
277.933
29.989
1.906
0.280
374.758
0.000
0.170
0.062
0.767
9.767
0.131
0.031
0.355
101.263
26.977
0.036
0.451
25.913
14.265
0.761
2.555
7.623
0.018
2.094
0.780
199.323
0.000
0.000
0.002
0.135
8.208
0.004
41.150
0.000
1.721
7.065
0.000
453.479
1.082
0.000
0.085
0.281
0.000
0.157
1.866
1.318
5.757
0.001
0.355
0.615
425.069
9.852
1.174
121.742
0.014
0.002
33.936
8.160
453.768
29.989
1.906
0.280
374.758
0.000
0.170
0.062
0.767
9.767
0.131
0.031
0.355
101.263
26.977
0.036
0.451
25.913
674.980
14.265
0.761
2.555
7.623
0.018
2.094
0.780
199.323
A-235
-------
10 References
(1 )http ://www. electronicstakeback. cotn/wp-
content/uploads/Facts_and_Figures_on_EWaste_and_Recycling.pdf (accessed 03/10/12)
(2)http: //ngm. nati onal geographi c. com/200 8/01 /hi gh-tech-trash/carr oil -text (accessed 03/10/12)
(3)http://www.rohs.eu/english/index.html (accessed 03/10/12)
(4)http://en.wikipedia.org/wiki/Waste Electrical and Electronic Equipment Directive
(accessed 03/10/12)
(5) "Fire-LCA Model: TV Case Study" Simonson, M.; Blomqvist, P.; Boldizar, A.; Moller, K.;
Resell, L.; Tullin, C.; Stripple, H.; Sundqvist, J. O. SP Report 2000:13 ISBN 91-7848-811-7
Printed in 2000.
(6) "Emissions from Fires Part I: Fire Retarded and Non-Fire Retarded TV-Sets" Blomqvist, P.;
Resell, L.; Simonson, M. Fire Tech.2004, 40, 39-58.
(7) "Emissions from Fires Part II: Fire Retarded and Non-Fire Retarded TV-Sets" Blomqvist, P.;
Resell, L.; Simonson, M. Fire Tech.2004, 40, 59-73.
(8) "A review of current flame retardant systems for epoxy resins" Weil, E. D.; Levchik, S. J.
Fire. Sci.2004, 22, 25-40.
(9) "Thermal decomposition, combustion and flame-retardancy of epoxy resins - a review of the
recent literature" Levchik, S. V.; Weil, E. D. Polym. Int.2004, 53, 1901-1929.
(10) "A Review of Recent Progress in Phosphorus-based Flame Retardants" Levchik, S. V.;
Weil, E. D. J. Fire Sci.2006, 24, 345-364.
(11 )http://www.epa.gov/dfe/pubs/proj ects/pcb/index.htm (accessed 03/10/12)
(12)http://www.epa.gov/dfe/pubs/projects/pcb/fullreport_pcb flame retardants report draft 11
_10_08_to_e.pdf (accessed 03/10/12)
(14) Cone Calorimeter: ASTM E1354-07 "Standard Heat Method for Heat and Visible Smoke
Release Rates for Materials and Products Using an Oxygen Consumption Calorimeter"
(15) "Full Scale Flammability Measures for Electronic Equipment" Bundy, M.; Ohlemiller, T.
NIST Technical Note 1461 August 2004, US Dept. of Commerce.
(16)"Bench-Scale Flammability Measures for Electronic Equipment" Bundy, M.; Ohlemiller, T.
NISTIR (National Institute of Standards and Technology Internal Report) 7031 July 2003, U.S.
Dept. of Commerce.
(17) "Mechanistic Study of the Combustion Behavior of Polymeric Materials in Bench-scale
Tests. I. Comparison between Cone Calorimeter and Traditional Tests" Costa, L.; Camino, G.;
Bertelli, G.; Borsini, G. Fire andMaterials 1995, 19, 133-142.
(18) "Oxygen Index: Correlations to Other Fire Tests" Weil, E. D.; Hirschler, M. M.; Patel, N.
G; Said, M. M.; Shakir, S. Fire andMaterials 1992, 16, 159-167.
(19) "Comprehensive fire behaviour assessment of polymeric materials based on cone
calorimeter investigations" Schartel, B.; Braun, U. e-Polymers 2003, No. 13. http://www.e-
polymers.org/papers/schartel_010403.pdf.
(20) "Cone calorimeter analysis of UL-94 V-rated plastics" Morgan, A. B.; Bundy, M. Fire and
Materials 2007, 31, 257-283.
(21) "Ignition performance of new and used motor vehicle upholstery fabrics" Spearpoint, M.;
Olenick, S. M.; Torero, J. L.; Steinhaus, T. Fire andMaterials 2005, 29, 265-282.
(22) "Assessment of Flame Retardancy in Polyolefin-Based Non-Halogen FR Compounds"
Cogen, J. M.; Whaley, P. D.; Lin, T. S.; Bolz, K. Proceedings of the International Wire and
Cable Symposium (2004).
A-236
-------
(23) "The Assessment of Full-Scale Fire Hazards from Cone Calorimeter Data" Petrella, R. V. J.
FireSci. 1994,72, 14-43.
(24)"Some comments on the use of cone calorimeter data" Schartel, B.; Bartholmai, M.; Knoll,
U. Pofym. Degrad. Stab. 2005, 88, 540-547.
(25) "Heat release rate measurements of thin samples in the OSU apparatus and the cone
calorimeter" Filipczak, R.; Crowley, S.; Lyon, R. E. Fire Safety Journal 2005, 40, 628-645.
(26) "Heat Release Rate: The Single Most Important Variable in Fire Hazard" Babrauskas, V.;
Peacock, R. D. Fire Safety Journal 1992, 18, 255-272
(27)"New Fire Classifications and Fire Test Methods for the European Railway Industry"
Duggan, G. J.; Grayson, S. J.; Kumar, S. Flame Retardants 2004 Proceedings, January 27-28,
2004, London, UK, Interscience Communications
A-237
------- |