EPA Document # EPA- 740-R1-7009
June 2017
United States Office of Chemical Safety and
Lil iim Environmental Protection Agency Pollution Prevention
Scope of the Risk Evaluation for
1-Bromopropane
CASRN: 106-94-5
June 2017
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TABLE OF CONTENTS
ACKNOWLEDGEMENTS 5
ABBREVIATIONS 6
EXECUTIVE SUMMARY 8
1 INTRODUCTION 11
1.1 Regulatory History 13
1.2 Assessment History 14
1.3 Data and Information Collection 15
2 SCOPE OF THE EVALUATION 17
2.1 Physical and Chemical Properties 17
2.2 Conditions of Use 18
2.2.1 Data and Information Sources 18
2.2.2 Identification of Conditions of Use 18
2.3 Exposures 26
2.3.1 Fate and Transport 26
2.3.2 Releases to the Environment 27
2.3.3 Presence in the Environment and Biota 28
2.3.4 Environmental Exposures 28
2.3.5 Human Exposures 28
2.3.5.1 Occupational Exposures 28
2.3.5.2 Consumer Exposures 30
2.3.5.3 General Population Exposures 30
2.3.5.4 Potentially Exposed or Susceptible Subpopulations 31
2.4 Hazards (Effects) 32
2.4.1 Environmental Hazards 32
2.4.2 Human Health Hazards 32
2.4.2.1 Non-Cancer Hazards 32
2.4.2.2 Genotoxicity and Cancer Hazards 34
2.4.2.3 Potentially Exposed or Susceptible Subpopulations 34
2.5 Initial Conceptual Models 34
2.5.1 Initial Conceptual Model for Industrial and Commercial Activities and Uses: Potential
Exposures and Hazards 35
2.5.2 Initial Conceptual Model for Consumer Activities and Uses: Potential Exposures and
Hazards 37
2.5.3 Initial Conceptual Model for Environmental Releases and Wastes: Potential Exposures and
Hazards 39
2.6 Initial Analysis Plan 41
2.6.1 Exposure 41
2.6.1.1 Environmental Releases 41
2.6.1.2 Environmental Fate 41
2.6.1.3 Environmental Exposures 42
2.6.1.4 Occupational Exposures 42
2.6.1.5 Consumer Exposures 42
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2.6.1.6 General Population 43
2.6.2 Hazards (Effects) 43
2.6.2.1 Environmental Hazards 43
2.6.2.2 Human Health Hazards 44
2.6.3 Risk Characterization 44
REFERENCES 45
APPENDICES 48
Appendix A REGULATORY HISTORY 48
A.l Federal Laws and Regulations 48
A.2 State Laws and Regulations 51
A.3 International Laws and Regulations 52
Appendix B PROCESS, RELEASE AND OCCUPATIONAL EXPOSURE INFORMATION 54
B.l Process Information 54
B.l.l Manufacture (Including Import) 54
B.l.1.1 Domestic Manufacture 54
B.l.1.2 Import 54
B.l.2 Processing and Distribution 54
B.l.2.1 Processing as a Reactant 54
B.l.2.2 Incorporated into Formulation, Mixture or Reaction Product 54
B.l.2.3 Incorporated into Article 54
B.l.2.4 Repackaging 55
B.l.2.5 Recycling 55
B.l.3 Uses 55
B.l.3.1 Solvents for Cleaning and Degreasing 55
B.l.3.2 Adhesives and Sealants 60
B.l.3.3 Agricultural Products (Non-pesticidal) 60
B.l.3.4 Cleaning and Furniture Care Products 60
B.l.3.5 Other Uses 60
B.1.4 Disposal 61
B.2 Occupational Exposure Data 61
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LIST OF TABLES
Table 1-1. Assessment History of 1-BP 15
Table 2-1. Physical and Chemical Properties of 1-BP 17
Table 2-2. Production Volume of 1-BP in CDR Reporting Period (2012 to 2015) 19
Table 2-3. Categories and Subcategories of Conditions of Use for 1-BP 22
Table 2-4. Environmental Fate Characteristics of 1-BP 27
LIST OF FIGURES
Figure 2-1. Initial 1-BP Life Cycle Diagram 21
Figure 2-2. Initial 1-BP Conceptual Model for Industrial and Commercial Activities and Uses: Potential
Exposures and Hazards 36
Figure 2-3. Initial 1-BP Conceptual Model for Consumer Activities and Uses: Potential Exposures and
Hazards 38
Figure 2-4. Initial 1-BP Conceptual Model for Environmental Releases and Wastes: Potential Exposures
and Hazards 40
LIST OF APPENDIX TABLES
Table_Apx A-l. Federal Laws and Regulations 48
Table_Apx A-2. State Laws and Regulations 51
Table_Apx A-3. Regulatory Actions by other Governments and Tribes 52
Table_Apx B-l. Summary of Industry Sectors with 1-BP Personal Monitoring Air Samples Obtained
from OSHA Inspections Conducted Between 2013 and 2016 61
LIST OF APPENDIX FIGURES
Figure_Apx B-l. Open Top Vapor Degreaser 56
Figure_Apx B-2. Open Top Vapor Degreaser with Enclosure 57
Figure_Apx B-3. Closed-Loop/Vacuum Vapor Degreaser 57
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ACKNOWLEDGEMENTS
This report was developed by the United States Environmental Protection Agency (U.S. EPA), Office of
Chemical Safety and Pollution Prevention (OCSPP), Office of Pollution Prevention and Toxics (OPPT).
Acknowledgments
The OPPT Assessment Team gratefully acknowledges participation or input from EPA's Office of
General Counsel, Office of Research and Development, Office of Children's Health Protection, and
assistance from EPA contractors CSRA LLC (Contract No. CIO-SP3, HHSN316201200013W), ERG
(Contract No. EP-W-12-006), ICF (Contract No. EPC14001), and SRC (Contract No. EP-W-12-003).
Docket
Supporting information can be found in public docket (Docket: EPA-HQ-QPPT-2( ).
Disclaimer
Reference herein to any specific commercial products, process or service by trade name, trademark,
manufacturer or otherwise does not constitute or imply its endorsement, recommendation or favoring
by the United States Government.
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ABBREVIATIONS
°C Degrees Celsius
ACGIH American Conference of Government Industrial Hygienists
atm Atmosphere(s)
ATSDR Agency for Toxic Substances and Disease Registry
BAF Bioaccumulation Factor
BCF Bioconcentration Factor
BMD Benchmark Dose Modeling
1-BP 1-Bromopropane
CAA Clean Air Act
CASRN Chemical Abstracts Service Registry Number
CBI Confidential Business Information
CDR Chemical Data Reporting
CEHD Chemical Exposure Health Data
CFC Chlorofluorocarbon
COC Concentration of Concern
CoCAM Cooperative Chemicals Assessment Meeting
CPCat Chemical and Product Categories
CSAC Chemical Safety and Advisory Council
CSCL Chemical Substances Control Law
DOE Department of Energy
DNA Deoxyribonucleic Acid
ECHA European Chemicals Agency
EPA Environmental Protection Agency
EPCRA Emergency Planning and Community Right-to-Know Act
FIFRA Federal Insecticide, Fungicide, and Rodenticide Act
g Gram(s)
HAP Hazardous Air Pollutant
HCFC Hydrochlorofluorocarbon
HPV High Production Volume
IMAP Inventory Multi-Tiered Assessment and Prioritisation
IRIS Integrated Risk Information System
ISHA Industrial Safety and Health Act
IUR Inhalation Unit Risk
kPa Kilopascal(s)
L Liter(s)
lb Pound(s)
Log Koc Logarithmic Soil Organic Carbon:Water Partitioning Coefficient
Log Kow Logarithmic Octanol:Water Partition Coefficient
m3 Cubic Meter(s)
mmHg Millimeter(s) of Mercury
mPa-s Millipascal(s)-Second
MSDS Material Safety Data Sheet
NAAQS National Ambient Air Quality Standards
NAICS North American Industry Classification System
NEI National Emissions Inventory
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NESHAP
National Emission Standards for Hazardous Air Pollutants
NICNAS
National Industrial Chemicals Notification and Assessment Scheme
NIH
National Institute of Health
NIOSH
National Institute of Occupational Safety and Health
NTP
National Toxicology Program
OCSPP
Office of Chemical Safety and Pollution Prevention
OECD
Organisation for Economic Co-operation and Development
OPPT
Office of Pollution Prevention and Toxics
OSHA
Occupational Safety and Health Administration
OTVD
Open Top Vapor Degreaser
PBPK
Physiologically Based Pharmacokinetic
PEL
Permissible Exposure Limit
PERC
Perchloroethylene
POD
Point of Departure
POTW
Publicly Owned Treatment Works
PPm
Part(s) per Million
QC
Quality Control
RA
Risk Assessment
RCRA
Resource Conservation and Recovery Act
REACH
Registration, Evaluation, Authorisation and Restriction of Chemicals
SDS
Safety Data Sheet
SIDS
Screening Information Data Set
SNAP
Significant New Alternatives Policy
SVHC
Substance of Very High Concern
TCCR
Transparent, Clear, Consistent, and Reasonable
TCE
Trichloroethylene
TLV
Threshold Limit Value
TRI
Toxics Release Inventory
TSCA
Toxic Substances Control Act
TWA
Time-Weighted Average
VOC
Volatile Organic Compound
U.S.
United States
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EXECUTIVE SUMMARY
TSCA § 6(b)(4) requires the U.S. Environmental Protection Agency (EPA) to establish a risk evaluation
process. In performing risk evaluations for existing chemicals, EPA is directed to "determine whether a
chemical substance presents an unreasonable risk of injury to health or the environment, without
consideration of costs or other non-risk factors, including an unreasonable risk to a potentially exposed
or susceptible subpopulation identified as relevant to the risk evaluation by the Administrator under
the conditions of use." In December of 2016, EPA published a list of 10 chemical substances that are
the subject of the Agency's initial chemical risk evaluations (81 FR 91927). as required by TSCA §
6(b)(2)(A). 1-Bromopropane (1-BP) was one of these chemicals.
TSCA § 6(b)(4)(D) requires that EPA publish the scope of the risk evaluation to be conducted, including
the hazards, exposures, conditions of use and potentially exposed or susceptible subpopulations that
the Administrator expects to consider. This document fulfills the TSCA § 6(b)(4)(D) requirement for 1-
BP.
This document presents the scope of the risk evaluation to be conducted for 1-BP. If a hazard,
exposure, condition of use or potentially exposed or susceptible subpopulation has not been discussed,
EPA, at this point in time, is not intending to include it in the scope of the risk evaluation. As per the
rulemaking, Procedures for Chemical Risk Evaluation Under the Amended Toxic Substances Control Act
(TSCA), with respect to conditions of use in conducting a risk evaluation under TSCA, EPA will first
identify "circumstances" that constitute "conditions of use" for each chemical. While EPA interprets
this as largely a factual determination—i.e., EPA is to determine whether a chemical substance is
actually involved in one or more of the activities listed in the definition—the determination will
inevitably involve the exercise of some discretion.
To the extent practicable, EPA has aligned this scope document with the approach set forth in the risk
evaluation process rule; however, the scope documents for the first 10 chemicals in the risk evaluation
process differ from the scope documents that EPA anticipates publishing in the future. Time
constraints have resulted in scope documents for the first 10 chemicals that are not as refined or
specific as future scope documents are anticipated to be.
Because there was insufficient time for EPA to provide an opportunity for comment on a draft of this
scope document, as it intends to do for future scope documents, EPA will publish and take public
comment on a Problem Formulation document which will refine the current scope, as an additional
interim step, prior to publication of the draft risk evaluation for 1-BP. This problem formulation is
expected to be released within approximately 6 months of publication of the scope.
1-BP is primarily used as a solvent cleaner in vapor and immersion degreasing operations to clean
optics, electronics and metals, but it has also been reported to be used as an alternative to ozone-
depleting substances and chlorinated solvents, as a solvent vehicle in industries using spray adhesives
such as foam cushion manufacturing. In the past, 1-BP was used as a solvent for fats, waxes or resins
and as an intermediate in pharmaceutical, insecticide, quaternary ammonium compound, flavor and
fragrance synthesis. Information from the 2016 Chemical Data Reporting (CDR) for 1-BP indicates the
reported production volume is 25.9 million lbs/year (manufacture and import).
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The initial conceptual models presented in Section 2 identify conditions of use; exposure pathways
(e.g., media); exposure routes (e.g., inhalation, dermal, oral); potentially exposed populations,
including potentially exposed or susceptible subpopulations; and hazards EPA expects to evaluate
based on the inherent hazards of 1-BP. It is expected that inhalation will be the primary route of
exposure to all populations.
This document presents the occupational scenarios in which workers and occupational non-users may
be exposed to 1-BP during a variety of conditions of use, such as spray adhesives, dry cleaning
(including spot cleaning) and degreasing (vapor, cold cleaning, and aerosol). It also presents the
consumer model which indicates exposures occurring from consumer uses for 1-BP such as aerosol and
spray adhesives, aerosol spot removers and aerosol cleaning and degreasing products. For 1-BP, EPA
believes that workers, consumers, and bystanders as well as certain other groups of individuals may
experience greater exposures than the general population. EPA will evaluate whether other groups of
individuals within the general population may be exposed via pathways that are distinct from the
general population due to unique characteristics (e.g., life stage, behaviors, activities, duration) or have
greater susceptibility than the general population, and should therefore be considered relevant
potentially exposed or susceptible subpopulations for purposes of this risk evaluation.
Exposures to the general population may occur from industrial releases. The manufacturing,
processing, distribution and use of 1-BP can result in releases to air, water, and soil. EPA expects to
consider exposures to the general population and the environment via inhalation of air emitted from
manufacturing, processing, distribution, use facilities and from water, sediments, soils that may receive
releases or wastes and disposal from such facilities.
A 2016 Draft Risk Assessment (U.S. EPA. 2016b) on 1-BP was previously released for public comment
(on March 2, 2016) and for a Chemical Safety and Advisory Council (CSAC) Peer Review (May 24-25,
2016) 1. 1-BP was recently listed on the Toxics Release Inventory (TRI/80 FR 72906). Data on the
environmental releases of 1-BP to air, landfills or water are likely to become available in the near term
through TRI. EPA also published a draft notice (January 9, 2017) on the rationale for granting the
petitions to add 1-BP to the list of hazardous air pollutants (HAPs).
1-BP has been the subject of numerous health hazard reviews including EPA's 2j iisk
Assessment (U.S. EPA. 2016b), the Agency for Toxic Substances and Disease Registry's (ATSDR's)
Toxicological Profile, and the National Institute for Occupational Safety and Health's (NIOSH's) Criteria
Document. Any existing assessments will be a starting point as EPA will conduct a systematic review of
the literature, including new literature since the existing assessments, as available in 1-Bromopropane
(CASRN 106-94-5) Bibliography: Supplemental File for the TSCA Scope Document, E PA-IHIQ-0 P PT-2016-
"" I i). In the 2CU Hi ah >isk Assessment. EPA reviewed the evidence for 1-BP toxicity and selected
liver toxicity, kidney toxicity, reproductive/developmental toxicity, neurotoxicity and cancer as the
most robust, sensitive and consistent adverse human health effects for risk characterization. In
addition, EPA did not assess environmental exposures from the selected uses of 1-BP in the 2016 Draft
Risk Assessment due to 1-BP's low persistence, low bioaccumulation and low hazard for aquatic
toxicity, as well as the expectation that low levels of 1-BP would be present in surface water. These
hazards will be evaluated based on the specific exposure scenarios identified.
1 The full February 2016 Draft Risk Assessment can be found at: https://www.epa,gov/sites/production/files/2016-
03/documents/l-BP report and appendices final,pdf.
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The initial analysis plan describes EPA's plan for conducting systematic review of readily available
information and identification of assessment approaches to be used in conducting the risk evaluation
for 1-BP. The initial analysis plan will be used to develop the problem formulation and final analysis
plan for the risk evaluation of 1-BP.
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1 INTRODUCTION
This document presents the scope of the risk evaluation to be conducted for 1-Bromopropane (1-BP). If
a condition of use has not been discussed, EPA, at this point in time, is not intending to include that
condition of use in the scope of the risk evaluation. Moreover, during problem formulation EPA may
determine that not all conditions of use mentioned in this scope will be included in the risk evaluation.
Any condition of use that will not be evaluated will be clearly described in the problem formulation
document.
On June 22, 2016, the Frank R. Lautenberg Chemical Safety for the 21st Century Act, which amended
the Toxic Substances Control Act (TSCA), the nation's primary chemicals management law, was signed
into law. The new law includes statutory requirements and deadlines for actions related to conducting
risk evaluations of existing chemicals.
TSCA § 6(b)(4) requires the U.S. Environmental Protection Agency (EPA) to establish a risk evaluation
process. In performing risk evaluations for existing chemicals, EPA is directed to "determine whether a
chemical substance presents an unreasonable risk of injury to health or the environment, without
consideration of costs or other non-risk factors, including an unreasonable risk to a potentially exposed
or susceptible subpopulation identified as relevant to the risk evaluation by the Administrator under
the conditions of use."
In December of 2016, EPA published a list of 10 chemical substances that are the subject of the
Agency's initial chemical risk evaluations (81 FR 91927), as required by TSCA § 6(b)(2)(A). These 10
chemical substances were drawn from the 2014 update of EPA's TSCA Work Plan for Chemical
Assessments, a list of chemicals that EPA identified in 2012 and updated in 2014 (currently totaling 90
chemicals) for further assessment under TSCA. EPA's designation of the first 10 chemical substances
constituted the initiation of the risk evaluation process for each of these chemical substances, pursuant
to the requirements of TSCA § 6(b)(4).
TSCA § 6(b)(4)(D) requires that EPA publish the scope of the risk evaluation to be conducted, including
the hazards, exposures, conditions of use and potentially exposed or susceptible subpopulations that
the Administrator expects to consider. On February 14, 2017, EPA convened a public meeting to
receive input and information to assist the Agency in its efforts to establish the scope of the risk
evaluations under development for the ten chemical substances designated in December 2016 for risk
evaluations pursuant to TSCA. EPA provided the public an opportunity to identify information, via oral
comment or by submission to a public docket, specifically related to the conditions of use for the ten
chemical substances. EPA used this information in developing this scope document, which fulfills the
TSCA § 6(b)(4)(D) requirement for 1-BP.
As per the rulemaking, Procedures for Chemical Risk Evaluation Under the Amended Toxic Substances
Control Act (TSCA), in conducting a risk evaluation under TSCA EPA will first identify "circumstances"
that constitute "conditions of use" for each chemical. While EPA interprets this as largely a factual
determination —i.e., EPA is to determine whether a chemical substance is actually involved in one or
more of the activities listed in the definition—the determination will inevitably involve the exercise of
some discretion. Based on legislative history, statutory structure and other evidence of Congressional
intent, EPA has determined that certain activities may not generally be considered to be conditions of
use. In exercising its discretion, for example, EPA would not generally consider that a single
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unsubstantiated or anecdotal statement (or even a few isolated statements) on the internet that a
chemical can be used for a particular purpose would necessitate concluding that this represented part
of the chemical substance's "conditions of use." As a further example, although the definition could be
read literally to include all intentional misuses (e.g., inhalant abuse), as a "known" or "reasonably
foreseen" activity in some circumstances, EPA does not generally intend to include such activities in
either a chemical substance's prioritization or risk evaluation. In addition, EPA interprets the mandates
under section 6(a)-(b) to conduct risk evaluations and any corresponding risk management to focus on
uses for which manufacture, processing, or distribution in commerce is intended, known to be
occurring, or reasonably foreseen (i.e., is prospective or on-going), rather than reaching back to
evaluate the risks associated with legacy uses, associated disposal, and legacy disposal, and interprets
the definition of "conditions of use" in that context. For instance, the conditions of use for purposes of
section 6 might reasonably include the use of a chemical substance in insulation where the
manufacture, processing or distribution in commerce for that use is prospective or on-going, but would
not include the use of the chemical substance in previously installed insulation, if the manufacture,
processing or distribution for that use is not prospective or on-going. In other words, EPA interprets
the risk evaluation process of section 6 to focus on the continuing flow of chemical substances from
manufacture, processing and distribution in commerce into the use and disposal stages of their
lifecycle. That said, in a particular risk evaluation, EPA may consider background exposures from legacy
use, associated disposal, and legacy disposal as part of an assessment of aggregate exposure or as a
tool to evaluate the risk of exposures resulting from non-legacy uses.
Furthermore, in exercising its discretion under section 6(b)(4)(D) to identify the conditions of use that
EPA expects to consider in a risk evaluation, EPA believes it is important for the Agency to have the
discretion to make reasonable, technically sound scoping decisions in light of the overall objective of
determining whether chemical substances in commerce present an unreasonable risk. Consequently,
EPA may, on a case-by case basis, exclude certain activities that EPA has determined to be conditions
of use in order to focus its analytical efforts on those exposures that are likely to present the greatest
concern meriting an unreasonable risk consideration. For example, EPA intends to exercise discretion
in addressing circumstances where the chemical substance subject to scoping is unintentionally
present as an impurity in another chemical substance that is not the subject of the pertinent scoping,
in order to determine which risk evaluation the potential risks from the chemical substance should be
addressed in. As an additional example, EPA may, on a case-by-case basis, exclude uses that EPA has
sufficient basis to conclude would present only "de minimis" exposures. This could include uses that
occur in a closed system that effectively precludes exposure, or use as an intermediate. During the
scoping phase, EPA may also exclude a condition of use that has been adequately assessed by another
regulatory agency, particularly where the other agency has effectively managed the risks.
The situations identified above are examples of the kinds of discretion that EPA will exercise in
determining what activities constitute conditions of use, and what conditions of use are to be included
in the scope of any given risk evaluation. See the preamble to Procedures for Chemical Risk Evaluation
Under the Amended Toxic Substances Control Act (TSCA) for further discussion of these issues.
To the extent practicable, EPA has aligned this scope document with the approach set forth in the risk
evaluation process rule; however, the scope documents for the first 10 chemicals in the risk evaluation
process differ from the scope documents that EPA anticipates publishing in the future. The first 10
chemical substances were not subject to the prioritization process that will be used in the future in
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accordance with amendments to TSCA. EPA expects to collect and screen much of the relevant
information about chemical substances that will be subject to the risk evaluation process during and
before prioritization. The volume of data and information about the first 10 chemicals that is available
to EPA is extremely large and EPA is still in the process of reviewing it, since the Agency had limited
ability to process the information gathered before issuing the scope documents for the first 10
chemicals. As a result of the statutory timeframes, EPA had limited time to process all of the
information gathered during scoping for the first 10 chemicals within the time provided in the statute
for publication of the scopes after initiation of the risk evaluation process. For these reasons, EPA's
initial screenings and designations with regard to applicability of data (e.g., on-topic vs. off-topic
information and data) may change as EPA progresses through the risk evaluation process. Likewise, the
Conceptual Models and Analysis Plans provided in the first 10 chemical scopes are designated as
"Initial" to indicate that EPA expects to further refine them during problem formulation.
The aforementioned time constraints have resulted in scope documents for the first 10 chemicals that
are not as refined or specific as future scope documents are anticipated to be. In addition, there was
insufficient time for EPA to provide an opportunity for comment on a draft of this scope document, as
it intends to do for future scope documents. For these reasons, EPA will publish and take public
comment on a problem formulation document which will refine the current scope, as an additional
interim step, prior to publication of the draft risk evaluations for the first 10 chemicals. This problem
formulation is expected to be released within approximately 6 months of publication of the scope.
1.1 Regulatory History
EPA conducted a search of existing domestic and international laws, regulations and assessments
pertaining to 1-Bromopropane (1-BP). EPA compiled this summary from data available from federal,
state, international and other government sources, as cited in Appendix A. During risk evaluation, EPA
will evaluate and consider the impact of these existing laws and regulations in the problem formulation
step to determine what, if any further analysis might be necessary as part of the risk evaluation.
Federal Laws and Regulations
1-BP is subject to federal statutes or regulations, other than TSCA, that are implemented by other
offices within EPA and/or other federal agencies/departments. A summary of federal laws, regulations
and implementing authorities is provided in Appendix A.l.
State Laws and Regulations
1-BP is subject to state statutes or regulations implemented by state agencies or departments. A
summary of state laws, regulations and implementing authorities is provided in Appendix A.2.
Laws and Regulations in Other Countries and International Treaties or Agreements
1-BP is subject to statutes or regulations in countries other than the United States and/or international
treaties and/or agreements. A summary of these laws, regulations, treaties and/or agreements is
provided in Appendix A.3.
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1.2 Assessment History
EPA has identified assessments conducted by other EPA Programs and other organizations (see Table
1-1). Depending on the source, these assessments may include information on conditions of use,
hazards, exposures and potentially exposed or susceptible subpopulations—information useful to EPA
in preparing this scope for risk evaluation. Table 1-1 shows the assessments that have been conducted.
In addition to using this information, EPA intends to conduct a full review of the data collected (see 1-
Bromopropane (CASRN106-94-5) Bibliography: Supplemental File for the TSCA Scope Document, EPA-
HQ-0PPT-2C ) using the literature search strategy (see Strategy for Conducting Literature
Searches for 1-Bromopropane: Supplemental File for the TSCA Scope Document EPA-HQ-Of
) to ensure that EPA is considering information that has been made available since these
assessments were conducted.
A 2016 Draft Risk Assessment (U.S. EPA. 2016b) on 1-BP was previously released for public comment2.
During scoping and problem formulation for the 2016 Draft Risk Assessment on 1-BP, EPA considered
all known TSCA uses, and focused on those that involved products with high 1-BP content, and those
that were emissive, exhibiting high potential for worker and/or consumer exposure. Occupational uses
of concern identified for 1-BP included its use in spray adhesives, dry cleaning (including spot cleaning)
and degreasing (vapor, cold cleaning and aerosol). Consumer uses identified for 1-BP included aerosol
spray adhesives, aerosol spot removers and aerosol cleaning and degreasing products, many of which
were identified to contain 60-100% 1-BP. EPA expects to consider all these uses identified in the 2016
Draft Risk Assessment. In addition, in the _2C ! • tNi atf L isk Assessment. EPA reviewed the evidence for
1-BP toxicity and selected liver toxicity, kidney toxicity, reproductive/developmental toxicity,
neurotoxicity and cancer as the most robust, sensitive and consistent adverse human health effects for
risk characterization. EPA expects to use these previous analyses and also expects to consider other
studies (e.g., more recently published, alternative test data) that have been published since the 2016
Draft Risk Assessment, as identified in the literature search conducted by the Agency for 1-BP (1-
Bromopropane (CASRN 106-94-5) Bibliography: Supplemental File for the TSCA Scope Document (EPA-
IHQ-OPPT-2C ). Furthermore, the identified activities/uses, exposure pathways, routes of
exposures, receptors, hazards and dose-response analyses conducted in the 2016 Draft Risk
Assessment were recently released for public comment (March 2016) and then subsequently peer
reviewed by the Chemical Safety and Advisory Council (CSAC) Peer Review (May 24-25, 2016; EPA-HQ-
QPPT-2015-0805-0028). EPA also expects to consider the comments received by the public as well as
the recommendations made by the CSAC peer reviewers to incorporate a life cycle approach that
includes manufacturing, processing, distribution and use activities/scenarios; exposures via dermal and
oral exposures; and additional receptors, for example, the general population and those populations
co-located with dry cleaning facilities that use 1-BP.
EPA also published a draft notice (January 9, 2017) on the rationale for granting the petitions to add 1-
BP to the list of hazardous air pollutants (HAPs), which included a review of both the exposure
potential and hazard characterization for 1-BP (htt ps://www. regulations.gov/document?D=E PA-HQ-
QAR-2014-0471-0062).
2 The full February 2016 Draft Risk Assessment can be found at: https://www.epa,gov/sites/production/files/2016-
03/documents/l-BP report and appendices final,pdf.
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Table 1-1. Assessment History of 1-BP
Authoring Organization
Assessment
EPA Assessments
Office of Chemical Safety and Pollution
Prevention (OCSPP)/Office of Pollution Prevention
and Toxics (OPPT)
TSCA work plan chemical risk assessment: Peer
review draft 1-bromopropane: (n-Propvl bromide)
sprav adhesives, drv cleaning, and degreasing uses
CASRN: 106-94-5 (2016b)
Office of Air Quality Planning and Standards
(OAQPS)
Draft notice to grant the petition to add 1-BP to
the list of HAPs
(https://www. regulations.gov/document?D=EPA-
HQ-OAR-2014-0471-0062)
Other U.S.-Based Organizations
National Institute for Occupational Safety and
Health (NIOSH)
Criteria for a Recommended Standard:
Occupational Exposure to 1-Bromopropane
(2016)
Agency for Toxic Substances and Disease Registry
(ATSDR)
Toxicological Profile for 1-Bromopropane
(2016)
1.3 Data and Information Collection
EPA/OPPT generally applies a process and workflow that includes: (1) data collection; (2) data
evaluation; and (3) data integration of the scientific data used in risk assessments developed under
TSCA. Scientific analysis is often iterative in nature as new knowledge is obtained. Hence, EPA/OPPT
expects that multiple refinements regarding data collection will occur during the process of risk
evaluation.
Data Collection: Data Search
EPA/OPPT conducted chemical-specific searches for data and information on: physical and chemical
properties; environmental fate and transport; conditions of use information; environmental exposures,
human exposures, including potentially exposed or susceptible subpopulations; ecological hazard,
human health hazard, including potentially exposed or susceptible subpopulations.
EPA/OPPT designed its initial data search to be broad enough to capture a comprehensive set of
sources containing data and/or information potentially relevant to the risk evaluation. Generally, the
search was not limited by date and was conducted on a wide range of data sources, including but not
limited to: peer-reviewed literature and gray literature (e.g., publicly-available industry reports, trade
association resources, government reports). When available, EPA/OPPT relied on the search strategies
from recent assessments, such as EPA Integrated Risk Information System (IRIS) assessments and the
National Toxicology Program's (NTP) Report on Carcinogens (NTP. 2013). to identify relevant references
and supplemented these searches to identify relevant information published after the end date of the
previous search to capture more recent literature. Strategy for Conducting Literature Searches for 1-
Bromopropane: Supplemental File for the TSCA Scope Document (EPA-HQ-QPPT-2016-0741) provides
details about the data sources and search terms that were used in the initial search.
Page 15 of 61
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Data Collection: Data Screening
Following the data search, references were screened and categorized using selection criteria outlined
in the Strategy for Conducting Literature Searches for 1-Bromopropane: Supplemental File for the TSCA
Scope Document (EPA-HQ-0IPPT-2016-0741). Titles and abstracts were screened against the criteria as
a first step with the goal of identifying a smaller subset of the relevant data to move into the
subsequent data extraction and data evaluation steps. Prior to full-text review, EPA/OPPT anticipates
refinements to the search and screening strategies, as informed by an evaluation of the performance
of the initial title/abstract screening and categorization process.
The categorization scheme (or tagging structure) used for data screening varies by scientific discipline
(i.e., physical and chemical properties; environmental fate and transport; chemical use/conditions of
use information; human and environmental exposures, including potentially exposed or susceptible
subpopulations identified by virtue of greater exposure; human health hazard, including potentially
exposed or susceptible subpopulations identified by virtue of greater susceptibility; and ecological
hazard), but within each data set, there are two broad categories or data tags: (1) on-topic references
or (2) off-topic references. On-topic references are those that may contain data and/or information
relevant to the risk evaluation. Off-topic references are those that do not appear to contain data or
information relevant to the risk evaluation. The Strategy for Conducting Literature Searches for 1-
Bromopropane: Supplemental File for the TSCA Scope Document (EPA-HQ-Of IP 1 > ¦ i i i i) discusses
the inclusion and exclusion criteria that EPA/OPPT used to categorize references as on-topic or off-
topic.
Additional data screening using sub-categories (or sub-tags) was also performed to facilitate further
sorting of data/information for example, identifying references by source type (e.g., published peer-
reviewed journal article, government report); data type (e.g., primary data, review article); human
health hazard (e.g., liver toxicity, cancer, reproductive toxicity); or chemical-specific and use-specific
data or information. These sub-categories are described in Strategy for Conducting Literature Searches
for 1-Bromopropane: Supplemental File for the TSCA Scope Document (IE IP A- IHIQ-0 IP PT-2016-0741) and
will be used to organize the different streams of data during the stages of data evaluation and data
integration steps of systematic review.
Results of the initial search and categorization results can be found in the 1-Bromopropane (CASRN
106-94-5) Bibliography: Supplemental File for the TSCA Scope Document f IE IP A-IH Q-Q IP IPT- 2C ).
This document provides a comprehensive list (bibliography) of the sources of data identified by the
initial search and the initial categorization for on-topic and off-topic references. Because systematic
review is an iterative process, EPA/OPPT expects that some references may move from the on-topic to
the off-topic categories, and vice versa. Moreover, targeted supplemental searches may also be
conducted to address specific needs for the analysis phase (e.g., to locate specific data needed for
modeling); hence, additional on-topic references not initially identified in the initial search may be
identified as the systematic review process proceeds.
Page 16 of 61
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2 SCOPE OF THE EVALUATION
As required by TSCA, the scope of the risk evaluation identifies the conditions of use, hazards,
exposures and potentially exposed or susceptible subpopulations that the Administrator expects to
consider. To communicate and visually convey the relationships between these components, EPA is
including an initial life cycle diagram and initial conceptual models that describe the actual or potential
relationships between 1-BP and human and ecological receptors. An initial analysis plan is also included
which identifies, to the extent feasible, the approaches and methods that EPA may use to assess
exposures, effects (hazards) and risks under the conditions of use of 1-BP. As noted previously, EPA
intends to refine this analysis plan during the problem formulation phase of risk evaluation.
2.1 Physical and Chemical Properties
Physical-chemical properties influence the environmental behavior and the toxic properties of a
chemical, thereby informing the potential conditions of use, exposure pathways and routes and
hazards that EPA intends to consider. For scope development, EPA considered the measured or
estimated physical-chemical properties set forth in Table 2-1.
Table 2-1. Physical and Chemical Properties of 1-BP
Property
Valuea
References
Molecular formula
C3H7Br
O'Neil (2013)
Molecular weight
122.99
O'Neil (2013)
Physical form
Colorless liquid; sweet hydrocarbon odor
O'Neil (2013)
Melting point
-110°C
O'Neil (2013)
Boiling point
71°C at 760 mmHg
O'Neil (2013)
Density
1.353 g/cm3 at 20°C
O'Neil (2013)
Vapor pressure
146.26 mmHg (19.5 kPa) at 20°C
Boublfk et al. (1984)
Vapor density
4.25 (relative to air)
Pattv et al. (1963)
Water solubility
2.450 g/L at 20°C
Yalkowskv et al. (2010)
Octanol/water partition
coefficient (Log Kow)
2.10
Hansch(1995)
Henry's Law constant
7.3xl0 3 atm-m3/mole (estimated)
U.S. EPA (2012a)
Flash point
22°C
O'Neil (2013)
Autoflammability
490°C
NFPA (2010)
Viscosity
5.241 mPa-sat 20°C
Havnes and Lide (2010)
Refractive index
1.4341
O'Neil (2013)
Dielectric constant
8.09 at 20°C
Havnes and Lide (2010)
a Measured unless otherwise noted.
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2.2 Conditions of Use
TSCA § 3(4) defines the conditions of use as "the circumstances, as determined by the Administrator,
under which a chemical substance is intended, known, or reasonably foreseen to be manufactured,
processed, distributed in commerce, used, or disposed of."
2.2.1 Data and Information Sources
As the first step in preparing these scope documents, EPA identified, based on
reasonably available information, the conditions of use for the subject chemicals. As further described
in this document, EPA searched a number of available data sources (e.g., Use and Market Profile for 1-
Bromopropane, EPA-HQ-OIPIPT-_!('»it -u I i). Based on this search, EPA published a preliminary list of
information and sources related to chemical conditions of use (see Preliminary Information on
Manufacturing, Processing, Distribution, Use, and Disposal: 1-Bromopropane, EPA-HQ-QPPT-2016-
0741-0003) prior to a February 2017 public meeting on scoping efforts for risk evaluation convened to
solicit comment and input from the public. EPA also convened meetings with companies, industry
groups, chemical users and other stakeholders to aid in identifying conditions of use and verifying
conditions of use identified by EPA. The information and input received from the public and
stakeholder meetings has been incorporated into this scope document to the extent appropriate, as
indicated in Table 2-3. Thus, EPA believes the manufacture, processing, distribution, use and disposal
activities identified in these documents constitute the intended, known, and reasonably foreseen
activities associated with the subject chemicals, based on reasonably available information.
The documents do not, in most cases, specify whether activity under discussion is intended, known, or
reasonably foreseen, in part due to the time constraints in preparing these documents.
2.2.2 Identification of Conditions of Use
As part of the scope, an initial life cycle diagram is provided (Figure 2-1) depicting the conditions of use
that are within the scope of the risk evaluation during various life cycle stages including manufacturing,
processing, use (industrial, commercial, consumer; when distinguishable), distribution and disposal.
The information is grouped according to Chemical Data Reporting (CDR) processing codes and use
categories (including functional use codes for industrial uses and product categories for industrial,
commercial and consumer uses), in combination with other data sources (e.g., published literature and
consultation with stakeholders), to provide an overview of conditions of use. EPA notes that some
subcategories of use may be grouped under multiple CDR categories.
For the purposes of this scope, CDR definitions were used. CDR use categories include the following:
"industrial use" means use at a site at which one or more chemicals or mixtures are manufactured
(including imported) or processed. "Commercial use" means the use of a chemical or a mixture
containing a chemical (including as part of an article) in a commercial enterprise providing saleable
goods or services. "Consumer use" means the use of a chemical or a mixture containing a chemical
(including as part of an article, such as furniture or clothing) when sold to or made available to
consumers for their use (U.S. EPA. 2016a).
To understand conditions of use relative to one another and associated potential exposures under
those conditions of use, the life cycle diagram includes the production volume associated with each
stage of the life cycle, as reported in the 2016 CDR reporting (U.S. EPA. 2016a), when the volume was
not claimed confidential business information (CBI). The 2016 CDR reporting data for 1-BP are provided
in Table 2-2 for 1-BP from EPA's CDR database (U.S. EPA. 2016a).
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Table 2-2. Production Volume of 1-BP in CD
R Reporting Period
(2012 to 2015) a
Reporting Year
2012
2013
2014
2015
Total Aggregate
Production Volume (lbs)
18,800,000
24,000,000
18,500,000
25,900,000
aThe CDR data for the 2016 reporting period is available via ChemView (https://iava.eoa.gov/chemview) (U.S. EPA.
2016a). Because of an ongoing CBI substantiation process reauired bv amended TSCA. the CDR data available in the scope
document is more specific than currently in ChemView.
According to data collected in EPA's 2016 Chemical Data Reporting (CDR) Rule, 25.9 million pounds of
1-BP were produced or imported in the United States in 2015 (U.S. EPA. 2016a). Data reported indicate
that there are two manufacturers and six importers of 1-BP in the United States. Additional companies
manufacturing or importing 1-BP are claimed as CBI.
Total production volume (manufacture plus import) of 1-BP has increased from 2012 to 2015, as can be
seen in Table 2-2 (U.S. EPA. 2016a). 1-BP's use has increased because it has been an alternative to
ozone-depleting substances and chlorinated solvents. Import volumes for 1-BP reported to the 2016
CDR are between 10 million and 25 million pounds per year (U.S. EPA. 2016a). In past years, import
data from 1-BP were claimed as CBI, but import data from other sources indicate that import volumes
of brominated derivatives of acyclic hydrocarbons (which includes 1-BP as well as other chemicals)
were 10.9 million pounds in 2007, which dropped to 10.3 million pounds in 2011 (NTP. 2013).
Figure 2-1 depicts the initial life cycle diagram for 1-BP from manufacture to the point of disposal. This
diagram does not distinguish between industrial, commercial and consumer uses; EPA will further
investigate and define the differences between these uses during problem formulation. Based on
market information from other sources, EPA expects degreasing and spray adhesive to be the primary
uses of 1-BP; however, the exact use volumes associated with these categories are claimed CBI in the
2016 CDR and are therefore not shown in the diagram (U.S. EPA. 2016a). Activities related to
distribution (e.g., loading, unloading) will be considered throughout the 1-BP life cycle, rather than
using a single distribution scenario. EPA expects that some commercial products containing 1-BP are
also available for purchase by consumers, such that many products are used in both commercial and
consumer applications/scenarios. EPA will further investigate 1-BP use in these products during the risk
evaluation process.
Descriptions of the industrial, commercial and consumer use categories identified from the 2016 CDR
and included in the life cycle diagram are summarized below (U.S. EPA. 2016a). The descriptions
provide a brief overview of the use category; Appendix B contains more detailed descriptions (e.g.,
process descriptions, worker activities, process flow diagrams, equipment illustrations) for each
manufacture, processing, distribution, use and disposal category. The descriptions provided below are
primarily based on the corresponding industrial function category and/or commercial and consumer
product category descriptions from the 2016 CDR and can be found in EPA's Instructions for Reporting
2016 TSCA Chemical Data Reporting (U.S. EPA 2016) (U.S. EPA. 2016a).
The "Solvents for Cleaning and Degreasing" category encompasses chemical substances used to
dissolve oils, greases and similar materials from a variety of substrates, including metal surfaces,
Page 19 of 61
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glassware and textile. This category includes the use of 1-BP in vapor degreasing, cold cleaning and in
industrial and commercial aerosol degreasing products.
The "Adhesives and Sealants" category encompasses chemical substances contained in adhesive and
sealant products used to fasten other materials together. EPA anticipates that a subcategory within the
Adhesives and Sealants category is the use of 1-BP as a solvent in spray adhesive for foam cushion
manufacturing. This category also covers uses of 1-BP in other adhesive products.
The "Cleaning and Furniture Care Products" category encompasses chemical substances contained in
products that are used to remove dirt, grease, stains and foreign matter from furniture and furnishings,
or to cleanse, sanitize, bleach, scour, polish, protect or improve the appearance of surfaces. This
category includes a wide variety of 1-BP uses, including, but not limited to, the use of 1-BP as dry
cleaning solvent, in spot cleaning formulations and in aerosol and non-aerosol type cleaners.
Page 20 of 61
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MFG/IMPORT
PROCESSING
INDUSTRIAL, COMMERCIAL, CONSUMER USES a
RELEASES and WASTE DISPOSAL
Manufacture
(Includes Import}
(25.8 million lbs)
Processing as Reactant
(Volume CBI)
Incorporated into
Formulation, Mixture,
or Reaction Product
(>1.31 million lbs)
Incorporated into
Article
(Volume CBI)
Repackaging
(>88,100 lbs)
3 ~
Recycling
Manufacture
(Includes Import)
Processing
Solvents for Cleaning and
Degreasing
(Volume CBI)
e.g., vapor degreaser, cold cleaner,
aerosoldegreaser
Adhesives and Sealants
(Volume CBI)
e.g., spray adhesive, aerosol spray
adhesive
Agricultural Products
(non pesticidal)
(37,400-3.33 million lbs)
e.g., misc. agricultural products
Cleaning and Furniture Care
Products
(714,000 lbs)
e.g., dry cleaning, spot cleaning,
aerosol cleaner and degreaser,
aerosol spot remover, non-aerosol
cleaner
Other Uses
e.g., lubricant, insulation, paintable
mold release product, refrigerant
Emissions to Air
Wastewater13
Liquid Wastesb
Solid Wastes
See Figure 2-4 for Environmental Releases
and Wastes
Uses. At the scope level of detail in the lifecycle diagram we are
not distinguishing between industrial/commercial/consumer
uses. The differences between these uses will be further
investigated and defined during risk evaluation.
Figure 2-1. Initial 1-BP Life Cycle Diagram
The initial life cycle diagram depicts the conditions of use that are within the scope of the risk evaluation during various life cycle stages
including manufacturing, processing, use (industrial, commercial, consumer), distribution and disposal. The production volumes shown are
for reporting year 2015 from the 2016 CDR reporting period (U.S. EPA. 2016a). Activities related to distribution (e.g., loading, unloading) will
be considered throughout the 1-BP life cycle, rather than using a single distribution scenario.
a See Table 2-3 for additional uses not mentioned specifically in this diagram,
bWastewater: combination of water and organic liquid, where the organic content is <50%. Liquid wastes: combination of water and organic liquid, where the organic
content is >50%.
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Table 2-3 summarizes each life cycle stage and the corresponding categories and subcategories of
conditions of use for 1-BP that EPA expects to consider in the risk evaluation. Using the 2016 CDR. EPA
identified industrial processing or use activities, industrial function categories and commercial and
consumer use product categories. EPA identified the subcategories by supplementing CDR data with
other published literature and information obtained through stakeholder consultations. For risk
evaluations, EPA intends to consider each life cycle stage (and corresponding use categories and
subcategories) and assess relevant potential sources of release and human exposure associated with
that life cycle stage.
Table 2-3. Categories and Subcategories of Conditions of Use for 1-BP
Life Cycle Stage
Categorya
Subcategory b
References
Manufacture
Domestic manufacture
Domestic manufacture
U.S. EPA (2016a)
Import
Import
U.S. EPA (2016a)
Processing
Processing as a
reactant
Intermediate in all other
basic inorganic chemical
manufacturing, all other
basic organic chemical
manufacturing, and
pesticide, fertilizer and other
agricultural chemical
manufacturing
U.S. EPA (2016a)
Processing -
Solvents for cleaning or
U.S. EPA (2016a)
incorporating into
formulation, mixture or
reaction product
degreasing in manufacturing
of:
- all other chemical product
and preparation
- computer and electronic
product
- electrical equipment,
appliance and component
- soap, cleaning compound
and toilet preparation
- services
Processing -
incorporating into
articles
Solvents (which become part
of product formulation or
mixture) in construction
U.S. EPA (2016a): Public
Comment, EPA-HQ-
OPPT-2016-0741-0017
Repackaging
Solvent for cleaning or
U.S. EPA (2016a)
degreasing in all other basic
organic chemical
manufacturing
Recycling
Recycling
U.S. EPA (2016a): Use
Document, EPA-HQ-
OPPT-2016-0741-0003
Page 22 of 61
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Life Cycle Stage
Categorya
Subcategory b
References
Distribution in
commerce
Distribution
Distribution
U.S. EPA (2016a): Use
Document, EPA-HQ-
OPPT-2016-0741-0003
Industrial/
commercial/
consumer use
Solvent (for cleaning or
degreasing)
Batch vapor degreaser (e.g.,
open-top, closed-loop)
U.S. EPA (2016b): Public
Comment, EPA-HQ-
OPPT-2016-0741-0014:
Public Comment, EPA-
HQ-OPPT-2016-0741-
0015; Public Comment,
EPA-HQ-OPPT-2016-
0741-0016
In-line vapor degreaser (e.g.,
conveyorized, web cleaner)
Kanegsberg and
Kanegsberg (2011);
Public Comment, EPA-
HQ-OPPT-2016-0741-
0014; Public Comment,
EPA-HQ-OPPT-2016-
0741-0016
Cold cleaner
U.S. EPA (2016b): Public
Comment, EPA-HQ-
OPPT-2016-0741-0016
Aerosol spray
degreaser/cleaner
U.S. EPA (2016b): Public
Comment, EPA-HQ-
OPPT-2016-0741-0016:
Public Comment, EPA-
HQ-OPPT-2016-0741-
0018; Public Comment,
EPA-HQ-OPPT-2016-
0741-0020
Adhesives and sealants
Adhesive chemicals - spray
adhesive for foam cushion
manufacturing and other
uses
U.S. EPA (2016b): Public
Comment, EPA-HQ-
OPPT-2016-0741-0016
Agricultural products
(non-pesticidal)
Miscellaneous agricultural
products
U.S. EPA (2016a)
Page 23 of 61
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Life Cycle Stage
Categorya
Subcategory b
References
Industrial/
commercial/
consumer use
(continued)
Cleaning and furniture
care products
Dry cleaning solvent
U.S. EPA (2016b): Public
Comment, EPA-HQ-
OPPT-2016-0741-0005:
Public Comment, EPA-
HQ-OPPT-2016-0741-
0016
Spot cleaner, stain remover
U.S. EPA (2016b): Public
Comment, EPA-HQ-
OPPT-2016-0741-0016:
Public Comment, EPA-
HQ-OPPT-2016-0741-
0022
Liquid cleaner (e.g., coin and
scissor cleaner)
Use Document, EPA-
HQ-OPPT-2016-0741-
0003
Liquid spray/aerosol cleaner
Use Document, EPA-
HQ-OPPT-2016-0741-
0003
Other uses
Arts, crafts and hobby
materials - adhesive
accelerant
U.S. EPA (2016b)
Automotive care products -
engine degreaser, brake
cleaner
Use Document, EPA-
HQ-OPPT-2016-0741-
0003
Anti-adhesive agents - mold
cleaning and release product
U.S. EPA (2016b): Public
Comment, EPA-HQ-
OPPT-2016-0741-0014:
Public Comment, EPA-
HQ-OPPT-2016-0741-
0015; Public Comment,
EPA-HQ-OPPT-2016-
0741-0016: Public
Comment, EPA-HQ-
OPPT-2016-0741-0018
Build ing/construction
materials not covered
elsewhere - insulation
Use Document, EPA-
HQ-OPPT-2016-0741-
0003; Public Comment,
EPA-HQ-OPPT-2016-
0741-0027
Page 24 of 61
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Life Cycle Stage
Categorya
Subcategory b
References
Industrial/
commercial/
consumer use
(continued)
Other uses
Electronic and electronic
products and metal products
U.S. EPA (2016a): Public
Comment, EPA-HQ-
OPPT-2016-0741-0016:
Public Comment, EPA-
HQ-OPPT-2016-0741-
0024
Functional fluids (closed
systems) - refrigerant
Use Document, EPA-
HQ-OPPT-2016-0741-
0003
Functional fluids (open
system) - cutting oils
Use Document, EPA-
HQ-OPPT-2016-0741-
0003; Public Comment,
EPA-HQ-OPPT-2016-
0741-0014
Other - asphalt extraction
Use Document, EPA-
HQ-OPPT-2016-0741-
0003; Public Comment,
EPA-HQ-OPPT-2016-
0741-0016
Temperature Indicator-
Laboratory chemicals
Use Document, EPA-
HQ-OPPT-2016-0741-
0003
Temperature Indicator-
Coatings
Use Document, EPA-
HQ-OPPT-2016-0741-
0003; Public Comment,
EPA-HQ-OPPT-2016-
0741-0014: Public
Comment, EPA-HQ-
OPPT-2016-0741-0016
Page 25 of 61
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Life Cycle Stage
Categorya
Subcategory b
References
Disposal
Emissions to air
Air
U.S. EPA (2017b): based
Wastewater
Industrial pre-treatment
on Toxic Release
Inventory (TRI)
information of other
work plan chemicals
Industrial wastewater
treatment
Publicly owned treatment
works (POTW)
including
trichloroethylene (TCE)
and perchloroethylene
(PERC)
Underground injection
Liquid and solid wastes
Municipal landfill
Hazardous landfill
Other land disposal
Municipal waste incinerator
Hazardous waste incinerator
Off-site waste transfer
aThese categories of conditions of use appear in the Life Cycle Diagram, reflect CDR codes and broadly represent
conditions of use of 1-BP in industrial and/or commercial settings.
bThese subcategories reflect more specific uses of 1-BP.
2.3 Exposures
For TSCA exposure assessments, EPA expects to evaluate exposures and releases to the environment
resulting from the conditions of use applicable to 1-BP. Post-release pathways and routes will be
described to characterize the relationship or connection between the conditions of use of 1-BP and the
exposure to human receptors, including potentially exposed or susceptible subpopulations and
ecological receptors. EPA will take into account, where relevant, the duration, intensity
(concentration), frequency and number of exposures in characterizing exposures to 1-BP.
2.3.1 Fate and Transport
Environmental fate includes both transport and transformation processes. Environmental transport is
the movement of the chemical within and between environmental media. Transformation occurs
through the degradation or reaction of the chemical with other species in the environment. Hence,
knowledge of the environmental fate of the chemical informs the determination of the specific
exposure pathways and potential human and environmental receptors EPA expects to consider in the
risk evaluation. Table 2-4 provides environmental fate data that EPA has identified and considered in
developing the scope for 1-BP.
Page 26 of 61
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Table 2-4. Environmental Fate Characteristics of 1-BP
Property or Endpoint
Valuea
References
Indirect photodegradation
9-12 days (estimated for atmospheric
degradation)
U.S. EPA (2016b)
Hydrolysis half-life
26 days
U.S. EPA (2016b)
Biodegradation
70% in 28 days (OECD 301C)
19.2% in 28 days (OECD 301D)
U.S. EPA (2016b)
Bioconcentration factor (BCF)
11 (estimated)
U.S. EPA (2012a)
Bioaccumulation factor (BAF)
12 (estimated)
U.S. EPA (2016b)
Organic carbon:water
partition coefficient (Log Koc)
1.6 (estimated)
U.S. EPA (2016b)
a Measured unless otherwise noted
1-BP is a water soluble, volatile liquid and mobile in soil. Adsorption to soils is not expected; therefore,
1-BP can migrate through soil to ground water. 1-BP is degraded by sunlight and reactants when
released to the atmosphere with a half-life of 9-12 days. Based on this estimated half-life in air, long-
range transport via the atmosphere is possible. Volatilization and microbial degradation influence the
fate of 1-BP when released to water, sediment or soil. Biotic and abiotic degradation rates ranging
from days to months have been reported.
Biotic and abiotic degradation studies have not shown this substance to be persistent (overall
environmental half-life of <2 months). No measured bioconcentration studies for 1-BP are available. An
estimated BCF of 11 and an estimated BAF of 12 suggest that bioconcentration and bioaccumulation
potential in aquatic organisms is low (BCF/BAF <1,000).
2.3.2 Releases to the Environment
Releases to the environment from conditions of use (e.g., industrial and commercial processes,
commercial or consumer uses resulting in down-the-drain releases) are one component of potential
exposure and may be derived from reported data that are obtained through direct measurement,
calculations based on empirical data and/or assumptions and models.
Based on its high volatility (vapor pressure of 146.26 mmHg at 20°C), 1-BP is expected to be released to
air during manufacturing, processing, distribution and use.
Wastes containing 1-BP may be present in either liquid form (e.g., spent solvent) or solid form (e.g.,
rags, wipe materials, transport containers with 1-BP residue). Industrial wastes containing 1-BP may be
incinerated. While 1-BP does not meet the definition of hazardous waste under the Resource
Conservation and Recovery Act (RCRA), it may be present in or co-mingled with solvent mixtures that
do meet the definition of hazardous waste under RCRA. Consumer wastes containing 1-BP may be
disposed with general municipal wastes, which may be incinerated or landfilled. Depending on the
incinerator destruction efficiency, the incineration of 1-BP may result in subsequent releases to air.
Landfilling wastes containing 1-BP may result in subsequent fugitive emissions to air or migration to
groundwater.
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In general, EPA expects that releases of 1-BP to wastewater are unlikely. However, TRI data for similar
solvents such as trichloroethylene suggest that water releases are possible. Therefore, this pathway is
included in the conceptual model for completeness.
A source of information that EPA expects to consider in evaluating releases to the environment are
data reported under the TRI program. EPA published a final rule on November 23, 2015 (80 FR 72906)
to add 1-BP to the TRI chemical list, as 1-BP meets the Emergency Planning and Community Right-to-
Know Act (EPCRA) Section 313(d)(2)(B) statutory listing criteria. Under this rule, 1-BP is reportable
beginning with the 2016 calendar year with the first reporting forms from facilities due by July 1, 2017.
For the 2016 reporting year, EPA expects that 140 facilities will file TRI reporting forms containing
release and waste management data for 1-BP. Facilities are required to report if they manufacture
(including import) or process more than 25,000 pounds of 1-BP, or if they otherwise use more than
10,000 pounds of 1-BP. EPA expects to consider these data in conducting the exposure assessment
component of the risk evaluation for 1-BP.
2.3.3 Presence in the Environment and Biota
Monitoring studies or a collection of relevant and reliable monitoring studies provide(s) information
that can be used in an exposure assessment. Monitoring studies that measure environmental
concentrations or concentrations of chemical substances in biota provide evidence of exposure.
Environmental monitoring data were not identified in the 2016 Draft Risk Assessment (U.S. EPA.
2016b); however, EPA expects to consider any environmental monitoring data that may result from the
updated literature search. Biomonitoring data were identified in the 2016 Draft Risk Assessment.
Several human and laboratory animal studies have investigated the utility of both urine and serum
bromide ion levels, as well as urinary metabolites, as biomarkers of human exposure to 1-BP. EPA
expects to consider the utility of this information in the risk evaluation.
2.3.4 Environmental Exposures
As shown in Figure 2-4, the manufacturing, processing, distribution, use and disposal of 1-BP can result
in releases to water, air, and soil. EPA expects to consider exposures to the environment and ecological
receptors that occur via these exposure pathways or media in conducting the risk evaluation for 1-BP.
2.3.5 Human Exposures
EPA expects to consider three broad categories of human exposures: occupational exposures,
consumer exposures and general population exposures. Subpopulations within these exposure
categories will also be considered as described herein.
2.3.5.1 Occupational Exposures
EPA expects to consider worker activities where there is a potential for exposure under the various
conditions of use described in Section 2.2. In addition, EPA expects to consider exposure to
occupational non-users, who do not directly handle the chemical but perform work in an area where
the chemical is present. When data and information are available to support the analysis, EPA also
expects to consider the effect(s) that engineering controls and/or personal protective equipment have
on occupational exposure levels.
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In the 2016 Draft Risk Assessment (U.S. EPA, 2016b), EPA evaluated inhalation exposures to 1-BP for
occupational use in spray adhesives, dry cleaning (including spot cleaning) and degreasing (vapor, cold
cleaning and aerosol). Based on information identified during this scoping, as described in Section 2.2,
additional conditions of use resulting in occupational exposures will be considered during the risk
evaluation.
Workers and occupational non-users may be exposed to 1-BP when performing activities associated
with the conditions of use described in Section 2.2, including, but not limited to:
• Unloading and transferring 1-BP to and from storage containers and to process vessels;
• Handling, transporting and disposing waste containing 1-BP;
• Using 1-BP in process equipment (e.g., vapor degreasing machine);
• Cleaning and maintaining equipment;
• Sampling chemicals, formulations or products containing 1-BP for quality control (QC);
• Applying formulations and products containing 1-BP onto substrates (e.g., spray applying
adhesive containing 1-BP onto furniture pieces);
• Performing other work activities in or near areas where 1-BP is used.
Based on these activities, EPA expects to consider inhalation exposure to vapor and mists and dermal
exposure, including skin contact with liquids and vapors for workers and occupational non-users. EPA
also expects to consider potential worker exposure through mists that deposit in the upper respiratory
tract and are swallowed.
The Occupational Safety and Health Administration (OSHA) has not set permissible exposure limits
(PELs) and the NIOSH has not recommended worker exposure limits (RELs) for 1-BP; however, NIOSH
recently proposed a REL of 0.3 ppm (Criteria for a Recommended Standard: Occupational Exposure to
1-Bromopropane (2016); 81 FR 7122, February 10, 2016). A revised document was released for
comment in January of 2017. The American Conference of Government Industrial Hygienists (ACGIH)
has recommended a Threshold Limit Value (TLV) of 0.1 ppm 8-hour time-weighted average (TWA) 1-BP
for workers (ATSDR, 2016). Also, ACGIH classifies 1-BP as a "confirmed animal carcinogen with
unknown relevance in humans" and the Department of Health and Human Services classifies 1-BP as
"reasonably anticipated to be a human carcinogen" based on NTPs Report on Carcinogens (NTP. 2013).
Key data that inform occupational exposure assessment and which EPA expects to consider
include: the OSHA Chemical Exposure Health Data (CEHD) and NIOSH Health Hazard Evaluation (HHE)
program data. OSHA data are workplace monitoring data from OSHA inspections. The inspections can
be random or targeted, or can be the result of a worker complaint. OSHA data can be obtained through
the OSHA Integrated Management Information System (IMIS) at
https://www.osha.gov/oshstats/index.html. Table_Apx B-l in Appendix B provides a summary of
industry sectors with 1-BP personal monitoring air samples obtained from OSHA inspections conducted
between 2013 and 2016. NIOSH HHEs are conducted at the request of employees, union officials, or
employers and help inform potential hazards at the workplace. HHEs can be downloaded at
https://www.cdc.gov/niosh/hhe/. During the problem formulation, EPA will review these data and
evaluate their utility in the risk evaluation.
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2.3.5.2 Consumer Exposures
1-BP can be found in consumer products and/or commercial products that are readily available for
public purchase at common retailers [EPA-HQ-OPPT-2C 003, Sections 3 and 4 (U.S. EPA.
2017a)] and can therefore result in exposures to consumers.
Exposures routes for consumers using products containing 1-BP may include inhalation of vapors and
mists (e.g., aerosol spray applications), dermal exposure to products, and oral exposure through mists
that deposit in the upper respiratory tract and are swallowed. Although less likely given the physical-
chemical properties, oral exposure may also include ingestion of 1-BP residue on hand/body.
The previous 2016 Draft Risk Assessment (U.S. EPA. 2016b) characterized inhalation exposures to 1-BP
from the following uses:
1. Aerosol spray adhesives
2. Aerosol spot removers
3. Aerosol cleaners and degreasers (including engine degreasing, brake cleaning and electronics
cleaning)
Acute inhalation exposures to consumers (such as residential users) and bystanders (those who may
not be actively engaged in the use of the product, but may be in the room of use) in residential settings
were assessed for the consumer uses identified in the 2016 Draft Risk Assessment (U.S. EPA. 2016b).
While it is anticipated that inhalation serves as the primary route of 1-BP exposure to consumers,
additional exposure pathways will be considered, including dermal exposure from skin contact with
liquids and vapor.
2.3.5.3 General Population Exposures
Wastewater/liquid wastes, solid wastes or air emissions of 1-BP could result in potential pathways for
oral, dermal, or inhalation exposure to the general population. EPA will consider each media, route,
and pathway to estimate general population exposures.
Inhalation
The volatility of 1-BP makes inhalation exposures a likely exposure pathway when 1-BP is released (via
air or as a result of waste disposal) during industrial/commercial use (see Figure 2-4). Inhalation of 1-BP
may also occur in indoor settings as a result of co-location with dry cleaning facilities that use 1-BP.
Based on these potential sources and pathways of exposure, EPA expects to consider inhalation
exposures to the general population that may result from the conditions of use of 1-BP.
Oral
There is the potential for oral exposure to 1-BP by ingestion of water from contaminated surface water
or ground water sources. Although incidental hand-to-mouth ingestion of soil may occur, adsorption to
soils is not expected since 1-BP is volatile and mobile in soil (see Section 2.3.1); therefore, ingestion of
soil is not expected to be a significant route of exposure and EPA is not expected to consider this route
of exposure in the risk evaluation.
Based on these potential sources and pathways of exposure, EPA expects to consider oral exposures to
the general population that may result from the conditions of use of 1-BP identified.
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Dermal
Dermal exposure via water could occur through contact with contaminated surface or ground waters.
Dermal exposure may also occur by contact with contaminated air in indoor settings (co-location with
dry cleaners), however based on the physical and chemical properties of 1-BP, this is not expected to
be the primary route of exposure.
Based on these potential sources and pathways of exposure, EPA does expect to consider dermal
exposures to the general population that may result from the conditions of use of 1-BP.
2.3.5.4 Potentially Exposed or Susceptible Subpopulations
TSCA requires that the determination of whether a chemical substance presents an unreasonable risk
include consideration of unreasonable risk to "a potentially exposed or susceptible subpopulation
identified as relevant to the risk evaluation" by EPA. TSCA § 3(12) states that "the term 'potentially
exposed or susceptible subpopulation' means a group of individuals within the general population
identified by the Administrator who, due to either greater susceptibility or greater exposure, may be at
greater risk than the general population of adverse health effects from exposure to a chemical
substance or mixture, such as infants, children, pregnant women, workers, or the elderly."
In this section, EPA addresses the potentially exposed or susceptible subpopulations identified as
relevant based on greater exposure. EPA will address the subpopulations identified as relevant based
on greater susceptibility in the hazard section.
Of the human receptors identified in the previous sections, EPA identifies the following as potentially
exposed or susceptible subpopulations due to their greater exposure that EPA expects to consider in
the risk evaluation:
• Workers and occupational non-users.
• Consumers and bystanders associated with consumer use. 1-BP has been identified as being
used in products available to consumers; however, only some individuals within the general
population may use these products. Therefore, those who do use these products are a
potentially exposed or susceptible subpopulation due to greater exposure.
• Other groups of individuals within the general population who may experience greater
exposures due to their proximity to conditions of use identified in Section 2.2 that result in
releases to the environment and subsequent exposures (e.g., individuals who live or work near
manufacturing, processing, distribution, use or disposal sites).
In developing scenarios, EPA will evaluate available data to ascertain whether some human receptor
groups may be exposed via exposure pathways that may be distinct to a particular subpopulation or
lifestage (e.g., children's crawling, mouthing or hand-to-mouth behaviors) and whether some human
receptor groups may have higher exposure via identified pathways of exposure due to unique
characteristics (e.g., activities, duration or location of exposure) when compared with the general
population (U.S. EPA. 2006a).
In summary, in the risk evaluation for 1-BP, EPA expects to consider the following potentially exposed
groups of human receptors: workers, occupational non-users, consumers, bystanders associated with
consumer use. As described above, EPA may also identify additional potentially exposed or susceptible
subpopulations that will be considered based on greater exposure.
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2.4 Hazards (Effects)
For scoping, EPA conducted comprehensive searches for data on hazards of 1-BP, as described in
Strategy for Conducting Scoping-Level Literature Searches for 1-Bromopropane: Supplemental File for
the TSCA Scope Document (EPA-HQ-0PPT-2C ). Based on initial screening, EPA expects to
consider the hazards of 1-BP identified in this scope document. However, when conducting the risk
evaluation, the relevance of each hazard within the context of a specific exposure scenario will be
judged for appropriateness. For example, hazards that occur only as a result of chronic exposures may
not be applicable for acute exposure scenarios. This means that it is unlikely that every hazard
identified in the scope will be considered for every exposure scenario.
2.4.1 Environmental Hazards
For scoping purposes, EPA consulted the following sources of environmental hazard data for 1-BP:
European Chemicals Agency (ECHA) (ECHA. 2017). However, EPA also expects to consider other studies
(e.g., more recently published, alternative test data) that have been published since these reviews, as
identified in the literature search conducted by the Agency for 1-BP (1-Bromopropane (CASRN 106-94-
5) Bibliography: Supplemental File for the TSCA Scope Document, EPA-HQ-Ol If 1 > ¦ j > > ¦ 1 i).
EPA expects to consider the hazards of 1-BP to aquatic organisms including fish, aquatic invertebrates
and algae potentially exposed under acute and chronic exposure conditions.
For the 2016 Draft Risk Assessment (U.S. EPA. 2016b), EPA reviewed and summarized available
published studies on ecotoxicity (U.S. EPA. 2012b, 1999) to understand the potential effects of 1-BP
releases on ecological receptors, including toxicity to fish, invertebrates, plants and birds. Based on
that review, EPA concluded that the acute toxicity of 1-BP to aquatic organisms was low based on
available data. The hazard of 1-BP was expected to be low for chronic aquatic organisms, sediment and
terrestrial species based on physical and chemical properties of 1-BP. The 2016 Draft Risk Assessment
contains a summary of the aquatic toxicity studies considered during the initial ecological hazard
evaluation for 1-BP.
2.4.2 Human Health Hazards
1-BP does not have an existing EPA IRIS Assessment; however, EPA has previously reviewed
data/information on health effects endpoints, identified hazards and conducted dose-response
analysis in the 2016 Draft Risk Assessment (U.S. EPA. 2016b); these hazard identification and dose-
response analyses on 1-BP have been recently peer reviewed (EPA-H1 115-0805-0028). EPA
expects to use these previous analyses. EPA also expects to consider other studies (e.g., more recently
published, alternative test data) that have been published since the 2016 Draft Risk Assessment, as
identified in the literature search conducted by the Agency for 1-BP (1-Bromopropane (CASRN 106-94-
5) Bibliography: Supplemental File for the TSCA Scope Document EPA-HQ-QPPT-2016-07411. EPA
expects to consider all potential hazards associated with 1-BP. Based on reasonably available
information, the following are the hazards that have been identified in previous government
documents and that EPA currently expects will likely be the focus of its analysis.
2.4.2.1 Non-Cancer Hazards
For the 20j; pyv -P.u-Il1. (\L;on 1-BP, EPA evaluated studies for the following
non-cancer hazards: acute toxicity (acute lethality at high concentrations only), blood toxicity,
immunotoxicity, cardiovascular toxicity, liver toxicity, kidney toxicity, reproductive toxicity,
developmental toxicity, and neurotoxicity. A comprehensive summary of all endpoints considered can
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be found in the 2016 Draft Risk Assessment. The following five health hazards were used for
quantitative risk characterization:
Liver Toxicity
Reported effects include liver histopathology (e.g., hepatocellular vacuolation, swelling, degeneration
and necrosis), increased liver weight and clinical chemistry changes indicative of hepatotoxicity [2016
Draft Risk Assessment (U.S. EPA. 2016b)1.
Kidney Toxicity
Laboratory animal studies have provided evidence of kidney toxicity following 1-BP exposure. Reported
kidney effects include increased organ weight, histopathology (pelvic mineralization, tubular casts) and
associated clinical chemistry changes (e.g., increased blood urea nitrogen) [2016 Draft Risk Assessment
(U.S. EPA. 2016b)1. Other kidney endpoints include increased incidence of pelvic mineralization in male
and female rats from a subchronic duration inhalation study.
Reproductive/Developmental Toxicity
A two-generation reproduction study in rats reported a variety of adverse effects on male and female
reproductive parameters (U.S. EPA, 2016b; WIL Research. 2001), including significant increases in the
number of implantation sites, decreases in mating indices, increased estrous cycle length, increased
numbers of females with evidence of mating without delivery, decreased absolute prostate and
epidydimal weights, decreased sperm motility and decreased mating and fertility indices. These
findings are supported by similar reports of reproductive toxicity from other laboratory studies with
rats and mice, including spermatogenic effects (decreased sperm count, altered sperm morphology
and decreased sperm motility), organ weight changes in males (decreased epididymis, prostate and
seminal vesicle weights), estrous cycle alterations and decreased numbers of antral follicles in females.
Developmental effects of 1-BP exposure have been evaluated on the basis of standard prenatal
developmental toxicity studies, and a two-generation reproductive toxicity study in rats exposed via
inhalation. Evidence for 1-BP-induced developmental toxicity includes dose-related adverse effects on
live litter size, postnatal survival, pup body weight, brain weight and skeletal development.
Neurotoxicity
Data from studies in humans and animals demonstrate that the nervous system is a sensitive target of
1-BP exposure. Both the central and peripheral nervous systems are affected. Most inhalation studies
using concentrations >1,000 ppm reported ataxia progressing to severely altered gait, hindlimb
weakness to loss of hindlimb control, convulsions and death [2016 Draft Risk Assessment (U.S. EPA.
2016b)]. Other effects include neuropathological changes such as peripheral nerve degeneration,
myelin sheath abnormalities and spinal cord axonal swelling. Brain pathology has also been reported in
several studies, including white and gray matter vacuolization, degeneration of Purkinje cells in the
cerebellum and decreased noradrenergic but not serotonergic axonal density in frontal cortex and
amygdala. Decreased brain weight has been reported in adult and developmental studies. In a two-
generation study, decreased brain weight in Fl-generation males was reported.
Human studies (case-control studies, industrial surveys and case reports) corroborate that the nervous
system is a sensitive target of 1-BP exposure in humans. Clinical signs of neurotoxicity (including
headache, dizziness, weakness, numbness in lower extremities, ataxia, paresthesias and changes in
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mood) and motor and sensory impairments were noted in the case reports of workers occupationally
exposed to 1-BP for 2 weeks to 3 years, and in industrial surveys ranging from 2 weeks to 9 years [2016
Draft Risk Assessment (U.S. EPA, 2016b)1.
2.4.2.2 Genotoxicity and Cancer Hazards
There is some evidence for mutagenicity and deoxyribonucleic acid (DNA) damage associated with
exposure to 1-BP in vitro, but the results are not conclusive as to whether and to what extent such
effects may occur in mammals in vivo. 1-BP was mutagenic with or without metabolic activation, but
other tests in bacteria for mutagenicity were negative. In vitro mammalian cell assays showed
increased mutation frequency, and DNA damage was significantly increased in human leukocytes;
however, tests conducted in vivo were mostly negative, including assays for dominant lethal mutations
and micronuclei induction. An evaluation of leukocytes in workers exposed to 1-BP showed no
definitive evidence of DNA damage. Positive results have been observed in several genotoxicity tests
using known or postulated metabolites of 1-BP.
In the 2016 Draft Risk Assessment (U.S. EPA. 2016b) on 1-BP, EPA evaluated cancer hazards from
studies in laboratory animals and humans following chronic (>10% of a lifetime (U.S. EPA. 2011))
inhalation exposures. Repeated exposures (e.g., >5 consecutive days) are anticipated during chronic
exposure. IBP has been shown to be a multi-target carcinogen in rats and mice. The exact
mechanism/mode of action of 1-BP carcinogenesis is not clearly understood, however, the weight-of-
evidence analysis for the cancer endpoint is sufficient to support a probable mutagenic mode of action
for 1-BP carcinogenesis. In the 2016 Draft Risk Assessment. EPA derived an inhalation unit risk (IUR)
based on lung tumors in female mice.
2.4.2.3 Potentially Exposed or Susceptible Subpopulations
TSCA requires that the determination of whether a chemical substance presents an unreasonable risk
include consideration of unreasonable risk to "a potentially exposed or susceptible subpopulation
identified as relevant to the risk evaluation" by EPA. TSCA § 3(12) states that "the term 'potentially
exposed or susceptible subpopulation' means a group of individuals within the general population
identified by the Administrator who, due to either greater susceptibility or greater exposure, may be at
greater risk than the general population of adverse health effects from exposure to a chemical
substance or mixture, such as infants, children, pregnant women, workers, or the elderly." In
developing the hazard assessment, EPA will evaluate available data to ascertain whether some human
receptor groups may have greater susceptibility than the general population to 1-BP's hazard(s).
In the 2016 Draft Risk Assessment (U.S. EPA. 2016b) on 1-BP, the evaluation of non-cancer risks
associated with acute exposures was based on developmental toxicity in a rodent study (WIL Research.
2001), which is representative of a sensitive subpopulation (i.e., adult women of child-bearing age and
their offspring). EPA consulted EPA's Guidelines for Developmental Toxicity Risk Assessment when
making the decision to use a developmental endpoint (i.e., decreased live litter size) as the basis of the
dose-response analysis for acute exposures. More detailed information on this conclusion can be found
in the 2016 Draft Risk Assessment.
2.5 Initial Conceptual Models
A conceptual model describes the actual or predicted relationships between the chemical substance
and receptors, either human or environmental. These conceptual models are integrated depictions of
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the conditions of use, exposures (pathways and routes), hazards and receptors. As part of the scope for
1-BP, EPA developed three conceptual models, presented here.
2.5.1 Initial Conceptual Model for Industrial and Commercial Activities and Uses:
Potential Exposures and Hazards
Figure 2-2 presents the initial conceptual model for human receptors from industrial and commercial
activities and uses of 1-BP. EPA anticipates that workers and occupational non-users may be exposed
to 1-BP via inhalation and dermal routes. EPA anticipates inhalation of vapor and mist as being the
most likely exposure routes. Certain conditions of use, such as maintenance of industrial degreasing
tanks, can also result in dermal exposure. EPA expects to consider potential exposure to mists that
deposit in the upper respiratory tract and are swallowed.
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INDUSTRIAL AND COMMERCIAL
ACTIVITIES / USES
EXPOSURE PATHWAY
EXPOSURE ROUTE
RECEPTORSF
HAZARDS
Manufacturing
Processing:
As reactant
Incorporated into
formulation, mixture
or reaction product
ncorporated into
article
Repackagin
~ Liquid Contact
Derma!
Workers*,
Hazards Potentially Associated with
Acute and/or Chronic Exposures:
See Section 2.4.2
Non-Users
Vapor/ Mist
~ Inhalation
Fugitive
Emissions
Recycling
Outdoor Air
(See Figure 2-4 for
Emissions to Air)
Solvents for Cleaning
and Deareasin
Adhesivesand Sealants
Stack
Emissions
Air Pollution Contro
cultural Products
(non pesticida
Populations in
Indoor Vapor from
Co-located Residences
and/or Businesses
Cleaning and Furniture
Care Products
Derma!, Oral
w Co-located Residences
Inhalation
and/or Businesses J
Other Uses
Workers
Occupational
Non-Users /
Waste Handling,
Treatment and Disposal
Liquid Contact, Vapor
Dermal, Inhalation
Wastewater, Uqutd Wastes and Solid Wastes
(See Figure 2-4)
Pathway{s) assessed inEPA's 2016 Draft Risk Assessment. See footnote a.
Figure 2-2. Initial 1-BP Conceptual Model for Industrial and Commercial Activities and Uses: Potential Exposures and Hazards
The conceptual model presents the exposure pathways, exposure routes and hazards to human receptors from industrial and commercial
activities and uses of 1-BP.
a 2016 Risk Assessment of 1-BP (U.S. EPA. 2016b) assessed vapor degreasing, cold cleaning and aerosol degreasing in industrial settings and dry cleaning and spot
cleaning in commercial settings (pathways shaded green).
bSome products are used in both commercial and consumer applications. Additional uses of 1-BP are included in Table 2-3.
c Stack air emissions are emissions that occur through stacks, confined vents, ducts, pipes or other confined air streams. Fugitive air emissions are those that are not
stack emissions and include fugitive equipment leaks from valves, pump seals, flanges, compressors, sampling connections, open-ended lines; evaporative losses from
surface impoundment and spills; and releases from building ventilation systems.
d Infiltration or re-uptake of outdoor air to indoor air from co-located residences and/or businesses.
e Exposure may occur through mists that deposit in the upper respiratory tract and are swallowed.
'Receptors include potentially exposed or susceptible subpopulations.
g When data and information are available to support the analysis, EPA also considers the effect that engineering controls and/or personal protective equipment have
on occupational exposure levels.
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2.5.2 Initial Conceptual Model for Consumer Activities and Uses: Potential
Exposures and Hazards
Figure 2-3 presents the conceptual model for human receptors from consumer uses of 1-BP. Similar to
Figure 2-2, EPA expects that consumers and bystanders may be exposed via inhalation, dermal and oral
routes, with inhalation of vapor and mist being the most likely exposure route. Figure 2-3 also shows
emissions of 1-BP to vapor/mist, as well as liquid wastes containing 1-BP. It should be noted that some
consumers may purchase and use products primarily intended for commercial use. Dermal exposure
from skin contact with liquids and vapor may also occur when performing certain activities associated
with use of some consumer products. Oral exposure may occur through mists that deposit in the
upper respiratory tract and are swallowed. Although less likely given the physical-chemical properties,
oral exposure may also occur from incidental ingestion of 1-BP residue on hand/body.
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CONSUMER ACTIVITIES / USES EXPOSURE PATHWAY EXPOSURE ROUTE RECEPTORS" HAZARDS
Consumers,
Bystanders
Consumers,
Bystanders
Wastewater, Liquid Wastes and Solid Wastes
(See Figure 2-4)
Liquid Contact
Vapor, Liquid Contact
Vapor/Mist
Inhalation
Dermal
Dermal', Oralc,
Inhalation
Consumer Handling and
Disposal of Waste
Agricultural Products
(non-pesticidal)
Adhesives and Sealantsa
e.g., aerosol spray adhesive
Other Uses b
e.g., lubricant, refrigerant,
mold cleaning and release
product
Hazards Potentially Associated with
Acute and/or Chronic Exposures:
See Section 2.4.2
Cleaning and Furniture Care
Products"
e.g., engine degreasing,
electronics cleaning, aerosol
spot remover
] Pathway(s) assessed in EPA's 2016 Draft Risk Assessment See footnote a.
Figure 2-3. Initial 1-BP Conceptual Model for Consumer Activities and Uses: Potential Exposures and Hazards
The conceptual model presents the exposure pathways, exposure routes and hazards to human receptors from consumer activities and
uses of 1-BP.
a 2016 Risk Assessment of 1-BP (U.S. EPA, 2016b) assessed vapor degreasing, cold cleaning and aerosol degreasing in industrial settings and dry cleaning and spot
cleaning in commercial settings (pathways shaded green).
bSome products are used in both commercial and consumer applications. Additional uses of 1-BP are included in Table 2-3.
c Dermal exposure may occur through skin contact with liquids and vapors; oral exposure may occur through mists that deposit in the upper respiratory tract and are
swallowed. Although less likely given the physical-chemical properties, oral exposure may also occur from incidental ingestion of residue on hand/body.
d Receptors include potentially exposed or susceptible subpopulations.
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2.5.3 Initial Conceptual Model for Environmental Releases and Wastes: Potential
Exposures and Hazards
Figure 2-4 illustrates exposure pathways for human and environmental receptors from environmental
releases and waste disposal activities.
EPA anticipates that general populations living near industrial and commercial facilities using 1-BP may
be exposed via inhalation of outdoor air. In addition, aquatic and terrestrial life may be exposed to 1-
BP contaminated water, sediment, and soil.
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RELEASES AND WASTES FROM EXPOSURE PATHWAY EXPOSURE ROUTE RECEPTORSc HAZARDS
INDUSTRIAL / COMMERCIAL / CONSUMER USES
Water,
Sediment
Aquatic
Species
Indirect discharge
Biosolids
General
Population
Ground
water
Soil
Waste Transport
Air
Terrestrial
Species
Human Health Pathway
Emissions to Air
POTW
Wastewater or
Liquid Wastes3
Underground
Injection
Inhalation
Oral
Off-site Waste
Transfer
Recycling, Other
Treatment b
Liquid Wastes
Solid Wastes
Incinerators
(Municipals
Hazardous Waste)
Industrial Pre-
Treatment or
Industrial WWT
Municipal,
Hazardous Landfill
or Other Land
Disposal
Hazards Potentially Associated with Acute
and/or Chronic Exposures:
See Section 2.4.1
Hazards Potentially Associated with Acute
and/or Chronic Exposures:
See Section 2.4.1
Hazards Potentially Associated with Acute
and/or Chronic Exposures:
See Section 2.4.2
Ecological Pathway
Figure 2-4. Initial 1-BP Conceptual Model for Environmental Releases and Wastes: Potential Exposures and Hazards
The conceptual model presents the exposure pathways, exposure routes and hazards to human and environmental receptors from
environmental releases and wastes of 1-BP,
a Additional releases may occur from recycling and other waste treatment and disposal activities
b Presence of mist is not expected. Dermal and oral exposure are expected to be low.
c Receptors include potentially exposed or susceptible subpopulations.
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2.6 Initial Analysis Plan
The initial analysis plan will be used to develop the eventual problem formulation and final analysis
plan for the risk evaluation. While EPA has conducted a search for readily available data and
information from public sources (1-Bromopropane (CASRN106-94-5) Bibliography: Supplemental File
for the TSCA Scope Document (EPA-HQ-QPPT-2016-0741) as described in Section 1.3, EPA encourages
submission of additional existing data, such as full study reports or workplace monitoring from industry
sources, that may be relevant for refining conditions of use, exposures, hazards and potentially
exposed or susceptible subpopulations.
The analysis plan outlined here is based on the conditions of use of 1-BP, as described in Section 2.2 of
this scope. The analysis plan may be refined as EPA proceeds with the systematic review of the
information in the 1-Bromopropane (CASRN 106-94-5) Bibliography: Supplemental File for the TSCA
Scope Document (EPA-HQ-QPPT-2016-0741). EPA will be evaluating the weight of the scientific
evidence for both hazard and exposure. Consistent with this approach, EPA will also use a systematic
review approach. As such, EPA will use explicit, pre-specified criteria and approaches to identify, select,
assess, and summarize the findings of studies. This approach will help to ensure that the review is
complete, unbiased, reproducible, and transparent.
2.6.1 Exposure
2.6.1.1 Environmental Releases
EPA expects to consider and analyze releases to environmental media as follows:
1) Review reasonably available published literature or information on processes and activities
associated with the conditions of use to evaluate the types of releases and wastes generated.
2) Review reasonably available chemical-specific release data, including measured or estimated
release data (e.g., data collected under the TRI and National Emissions Inventory [NEI]
programs).
3) Review reasonably available measured or estimated release data for surrogate chemicals that
have similar uses, volatility, chemical and physical properties.
4) Understand and consider regulatory limits that may inform estimation of environmental
releases.
5) Review and determine applicability of Organization for Economic Co-operation and
Development (OECD) Emission Scenario Documents and EPA Generic Scenarios to estimation of
environmental releases.
6) Evaluate the weight of the evidence of environmental release data.
7) Map or group each condition(s) of use to a release assessment scenario.
2.6.1.2 Environmental Fate
EPA expects to consider and analyze fate and transport in environmental media as follows:
1) Review reasonably available measured or estimated environmental fate endpoint data
collected through the literature search.
2) Using measured data and/or modeling, determine the influence of environmental fate
endpoints (e.g., persistence, bioaccumulation, partitioning, transport) on exposure pathways
and routes of exposure to human and environmental receptors.
3) Evaluate the weight of the evidence of environmental fate data.
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2.6.1.3 Environmental Exposures
EPA expects to consider the following in developing its environmental exposure assessment of 1-BP:
1) Review reasonably available environmental and biological monitoring data for all media
relevant to environmental exposure.
2) Review reasonably available information on releases to determine how modeled estimates of
concentrations near industrial point sources compare with available monitoring data. Available
exposure models will be evaluated and considered alongside available monitoring data to
characterize environmental exposures. Modeling approaches to estimate surface water
concentrations, sediment concentrations and soil concentrations generally consider the
following inputs: release into the media of interest, fate and transport and characteristics of the
environment.
3) Review reasonably available biomonitoring data. Consider whether these monitoring data could
be used to compare with species or taxa-specific toxicological benchmarks.
4) Determine applicability of existing additional contextualizing information for any monitored
data or modeled estimates during risk evaluation. Review and characterize the spatial and
temporal variability, to the extent that data are available, and characterize exposed aquatic and
terrestrial populations.
5) Evaluate the weight of evidence of environmental occurrence data and modeled estimates.
6) Map or group each condition(s) of use to environmental assessment scenario(s).
2.6.1.4 Occupational Exposures
EPA expects to consider and analyze both worker and occupational non-user exposures as follows:
1) Review reasonably available exposure monitoring data for specific condition(s) of use. Exposure
data to be reviewed may include workplace monitoring data collected by government agencies
such as OSHA and the National Institute of Occupational Safety and Health (NIOSH), and
monitoring data found in published literature (e.g., personal exposure monitoring data (direct
measurements) and area monitoring data (indirect measurements).
2) Review reasonably available exposure data for surrogate chemicals that have uses, volatility
and chemical and physical properties similar to 1-BP.
3) For conditions of use where data are limited or not available, review existing exposure models
that may be applicable in estimating exposure levels.
4) Review reasonably available data that may be used in developing, adapting or applying
exposure models to the particular risk evaluation.
5) Consider and incorporate applicable engineering controls and/or personal protective
equipment into exposure scenarios.
6) Evaluate the weight of evidence of occupational exposure data.
7) Map or group each condition of use to occupational exposure assessment scenario(s).
2.6.1.5 Consumer Exposures
EPA expects to consider and analyze both consumers using a consumer product and bystanders
associated with the consumer using the product as follows:
1) Review reasonably available consumer product-specific exposure data related to consumer
uses/exposures.
2) Evaluate the weight of the evidence of consumer exposure data.
3) For exposure pathways where data are not available, review existing exposure models that may
be applicable in estimating exposure levels.
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4) Review reasonably available data that may be used in developing, adapting or applying
exposure models to the particular risk evaluation. For example, existing models developed for a
chemical assessment may be applicable to another chemical assessment if model parameter
data are available.
5) Review reasonably available consumer product-specific sources to determine how those
exposure estimates compare with those reported in monitoring data.
6) Review reasonably available population- or subpopulation-specific exposure factors and activity
patterns to determine if potentially exposed or susceptible subpopulations need be further
refined.
7) Map or group each condition of use to consumer exposure assessment scenario(s).
2.6.1.6 General Population
EPA expects to consider and analyze general population exposures as follows:
1) Review reasonably available environmental and biological monitoring data for media to which
general population exposures are expected. For exposure pathways where data are not
available, review existing exposure models that may be applicable in estimating exposure
levels.
2) Consider and incorporate applicable media-specific regulations into exposure scenarios or
modeling.
3) Review reasonably available data that may be used in developing, adapting or applying
exposure models to the particular risk evaluation. For example, existing models developed for a
chemical assessment may be applicable to another chemical assessment if model parameter
data are available.
4) Review reasonably available information on releases to determine how modeled estimates of
concentrations near industrial point sources compare with available monitoring data.
5) Review reasonably available population- or subpopulation-specific exposure factors and activity
patterns to determine if potentially exposed or susceptible subpopulations need be further
defined.
6) Evaluate the weight of the evidence of general population exposure data.
7) Map or group each condition of use to general population exposure assessment scenario(s).
2.6.2 Hazards (Effects)
2.6.2.1 Environmental Hazards
EPA expects to consider and analyze environmental hazards as follows:
1) Review reasonably available environmental hazard data, including data from alternative test
methods (e.g., computational toxicology and bioinformatics; high-throughput screening
methods; data on categories and read-across; in vitro studies).
2) Conduct hazard identification (the qualitative process of identifying acute and chronic
endpoints) and concentration-response assessment (the quantitative relationship between
hazard and exposure) for all identified environmental hazard endpoints.
3) Derive concentrations of concern (COC) for all identified endpoints.
4) Evaluate the weight of the evidence of environmental hazard data.
5) Consider the route(s) of exposure, available biomonitoring data and available approaches to
integrate exposure and hazard assessments.
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2.6.2.2 Human Health Hazards
EPA expects to consider and analyze human health hazards as follows:
1) Review reasonably available human health hazard data, including data from alternative test
methods (e.g., computational toxicology and bioinformatics; high-throughput screening
methods; data on categories and read-across; in vitro studies; systems biology).
2) In evaluating reasonably available data, determine whether particular human receptor groups
may have greater susceptibility to the chemical's hazard(s) than the general population.
3) Conduct hazard identification (the qualitative process of identifying non-cancer and cancer
endpoints) and dose-response assessment (the quantitative relationship between hazard and
exposure) for all identified human health hazard endpoints.
4) Derive points of departure (PODs) where appropriate; conduct benchmark dose modeling
(BMD) depending on the available data. Adjust the PODs as appropriate to conform (e.g., adjust
for duration of exposure) to the specific exposure scenarios evaluated.
5) Evaluate the weight of the evidence of human health hazard data.
6) Consider the route(s) of exposure (oral, inhalation, dermal), available route-to-route
extrapolation approaches, available biomonitoring data and available approaches to correlate
internal and external exposures to integrate exposure and hazard assessment.
2.6.3 Risk Characterization
Risk characterization is an integral component of the risk assessment process for both ecological and
human health risks. EPA will derive the risk characterization in accordance with EPA's Risk
Characterization Handbook (U.S. EPA. 2000). As defined in EPA's Risk Characterization Policy, "the risk
characterization integrates information from the preceding components of the risk evaluation and
synthesizes an overall conclusion about risk that is complete, informative and useful for decision
makers." Risk characterization is considered to be a conscious and deliberate process to bring all
important considerations about risk, not only the likelihood of the risk but also the strengths and
limitations of the assessment, and a description of how others have assessed the risk into an
integrated picture.
Risk characterization at EPA assumes different levels of complexity depending on the nature of the risk
assessment being characterized. The level of information contained in each risk characterization varies
according to the type of assessment for which the characterization is written. Regardless of the level of
complexity or information, the risk characterization forTSCA risk evaluations will be prepared in a
manner that is transparent, clear, consistent, and reasonable (TCCR) (U.S. EPA. 2000). EPA will also
present information in this section consistent with approaches described in the Risk Evaluation
Framework Rule.
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REFERENCES
ATSDR (Agency for Toxic Substances and Disease Registry). (2016). Draft toxicological profile forl-
bromopropane. Atlanta, GA: Division of Toxicology and Human Health Sciences, Environmental
Toxicology Branch, https://www.atsd r.cde.g Profiles/tp209.pdf
Blando. JD; Schill, DP; De La Cruz. MP; Zhang. L; Zhang. J. (2010). Preliminary study of propyl bromide
exposure among New Jersey dry cleaners as a result of a pending ban on perchloroethylene. J
Air Waste Manag Assoc 60: 1049-1056. http://dx.doi.Org/10.3155/1047-3289.60.9.1049
Boubli'k, T; Fried. ¥; Hala, E. (1984). The vapour pressures of pure substances: Selected values of the
temperature dependence of the vapour pressures of some pure substances in the normal and
low pressure region. In Physical Sciences Data, vol 17 (2nd Revised ed.). Amsterdam, The
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pressures-of-pure~substances/boubl~k/978~0-444-42266-8
CDC (Centers for Disease Control and Prevention). (2016). Criteria for a recommended standard:
Occupational exposure to 1-bromopropane. (CDC-2016-0003). Cincinnati, OH: National Institute
for Occupational Safety and Health.
https://www.cdc.gov/niosh/docket/review/docket057a/pdfs/ctd~l~bpcriteriadocument final-
012616.pdf
Durkee. J. (2014). Cleaning with Solvents: Methods and Machinery. Oxford, UK: Elsevier Inc.
ECHA (European Chemicals Agency). (2017). Registration Dossier 1-Bromopropane. Available online at
https://echa.europa.eu/substance-information/Vsubsta nceinfo/100.003.133
Hansch. C. (1995). Fundamentals and Applications in Chemistry and Biology - Hydrophobic, Electronic
and Steric Constants. In Exploring QSAR. Washington DC: American Chemical Society
Professional Reference Book/Oxford University Press.
Haynes, WM; Lide. DR. (2010). CRC handbook of chemistry and physics : a ready-reference book of
chemical and physical data (91st ed. ed.). Boca Raton, Fla.: CRC.
http://www, world cat, i c/540161491?referer=xid
Ichihara. G; Li. W; Shibata. E; Ding, X: Wang, H; Liang. Y; Peng. S: Itohara, S; Kamiiima, M; Fan. Q: Zhang,
Y,_ 'hong. E; Wu. X: Valentine. WM; Takeuchi, Y. (2004). Neurologic abnormalities in workers of
a 1-bromopropane factory. Environ Health Perspect 112: 1319-1325.
http://dx.doi.org/10.1289/ehp.6995
Kanegsberg. B; Kanegsberg. E. (2011). Handbook of Critical Cleaning, Applications, Processes, and
Controls. Boca Raton: CRC Press, http://dx.doi.org/10.1201/bl0858
NEWMOA (Northeast Waste Management Officials' Association). (2001). Pollution prevention
technology profile - Closed loop vapor degreasing. Boston, MA.
http://www.newmoa.org/prevention/p2tech/ProfileVaporDegreasing.pdf
NFPA (National Fire Protection Association). (2010). Fire Protection Guide to Hazardous Materials.
Quincy, MA.
NIOSH (National Institute for Occupational Safety and Health). (1997). Control of health and safety
hazards in commercial drycleaners: chemical exposures, fire hazards, and ergonomic risk
factors. (DHHS (NIOSH) Publication Number 97-150). Atlanta, GA.
http://www.cdc.gov/niosh/docs/97~150/
NTP (National Toxicology Program). (2013). Draft report on carcinogens, monograph for 1-
bromopropane. Research Triangle Park, NC.
http://ntp.niehs.nih.gov/ntp/about ntp/monopeerrvw/2013/march/draftroclbpmonograph 5
08.pdf
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O'Neil, MJ. (2013). The Merck index: An encyclopedia of chemicals, drugs, and biologicals. In MJ O'Neil
(Ed.), (15th ed.). Cambridge, UK: Royal Society of Chemistry.
OSHA (Occupational Safety & Health Administration). (2017). Chemical Exposure Health Data (CEHD)
provided by OSHA to EPA. U.S. Occupational Safety and Health Administration.
Patty, FA: Fassett. DW; Irish, DP. (1963). Industrial hygiene and toxicology: Vol. II: Toxicology. In FA
Patty; DW Fassett; DD Irish (Eds.), (2nd revised ed.). New York, NY: Interscience Publishers.
TURI (Toxics Use Reduction Institute). (2012). Assessment of Alternatives to the Perchloroethylene for
Dry Cleaning Industry. Available online at
http://www.turi.or ' blications/TURI Methods Policy Reports/Assessment of Alterna
tives to Perchloroethylene for the Dry Cleaning Industry. 2012
U.S. EPA (U.S. Environmental Protection Agency). (1977). Control of volatile organic emissions from
solvent metal cleaning [EPA Report]. (EPA-450/2-77-022). Research Triangle Park, NC: U.S.
Environmental Protection Agency, Office of Air and Waste Management, Office of Air Quality
Planning and Standards.
U.S. EPA (U.S. Environmental Protection Agency). (1980). Compilation of air pollutant emission factors.
Chapter 4.7: Waste solvent reclamation. Office of Air and Radiation, Office of Air Quality and
Planning Standards.
U.S. EPA (U.S. Environmental Protection Agency). (1981). AP-42. Compilation of air pollutant emission
factors. Chapter 4. 6: Solvent degreasing. Washington, DC.
http://www3.epa.gov/ttn/chief/ap42/ch04/final/c4s06.pdf
U.S. EPA (U.S. Environmental Protection Agency). (1999). Category for persistent, bioaccumulative, and
toxic new chemical substances. Fed Reg 64: 60194-60204.
U.S. EPA (U.S. Environmental Protection Agency). (2000). Science policy council handbook: Risk
characterization (pp. 1-189). (EPA/100/B-00/002). Washington, D.C.: U.S. Environmental
Protection Agency, Science Policy Council, https://www.epa.gov/risk/risk~characterization~
handbook
U.S. EPA (U.S. Environmental Protection Agency). (2001). Guide to industrial assessments for pollution
prevention and energy efficiency [EPA Report]. (EPA/625/R-99/003). Cincinnati, OH: Office of
Research and Development, National Risk Management Research Laboratory, Center for
Environmental Research Information.
U.S. EPA (U.S. Environmental Protection Agency). (2004). Guidance document for the halogenated
solvent cleaning NESHAP. (EPA-453/R-94-081). RTP, NC: Office of Air Quality Planning and
Standards.
U.S. EPA (U.S. Environmental Protection Agency). (2006a). A framework for assessing health risk of
environmental exposures to children (pp. 1-145). (EPA/600/R-05/093F). Washington, DC: U.S.
Environmental Protection Agency, Office of Research and Development, National Center for
Environmental Assessment. http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=158363
U.S. EPA (U.S. Environmental Protection Agency). (2006b). Risk assessment for the halogenated solvent
cleaning source category [EPA Report]. (EPA Contract No. 68-D-01-052). Research Triangle Park,
NC: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards.
http://www3.epa.gov/airtoxics/degrea/residrisk2008.pdf
U.S. EPA (U.S. Environmental Protection Agency). (2011). Exposure factors handbook: 2011 edition
(final) [EPA Report]. (EPA/600/R-090/052F). Washington, DC: U.S. Environmental Protection
Agency, Office of Research and Development, National Center for Environmental Assessment.
http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=236252
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U.S. EPA (U.S. Environmental Protection Agency). (2012a). Estimation Programs Interface (EPI) Suite™
for Microsoft® Windows (Version 4.11). Washington D.C.: Environmental Protection Agency.
Retrieved from http://www.epa.gov/opptintr/exposure/pubs/episuite.htm
U.S. EPA (U.S. Environmental Protection Agency). (2012b). Sustainable futures P2 framework manual
[EPA Report], (EPA-748-B12-001). Washington DC. http://www.epa.gov/sustainable~
futures/sustainable~futures-p2~framework~manual
U.S. EPA (U.S. Environmental Protection Agency). (2014). Degreasing with TCE in commercial facilities:
Protecting workers [EPA Report]. Washington, DC: U.S. Environmental Protection Agency, Office
of Pollution Prevention and Toxics.
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reporting (May 2017 release). Washington, DC: US Environmental Protection Agency, Office of
Pollution Prevention and Toxics. Retrieved from https://www.epa.gov/chemical-data-reporting
U.S. EPA (U.S. Environmental Protection Agency). (2016b). TSCA work plan chemical risk assessment:
Peer review draft 1-bromopropane: (n-Propyl bromide) spray adhesives, dry cleaning, and
degreasing uses CASRN: 106-94-5 [EPA Report]. (EPA 740-R1-5001). Washington, DC.
https://www.epa.gov/sites/production/files/2016-03/documents/l-
bp report and appendices final.pdf
U.S. EPA (U.S. Environmental Protection Agency). (2017a). Preliminary Information on Manufacturing,
Processing, Distribution, Use, and Disposal: 1-Bromopropane. Support document for Docket
EPA-HQ-OPPT-2016-0741. Washington, DC: Office of Chemical Safety and Pollution Prevention.
https://www.epa.gov/sites/production/files/2017-02/documents/l-bromopropane.pdf
U.S. EPA (U.S. Environmental Protection Agency). (2017b). Toxics Release Inventory (TRI). Retrieved
from https://www.epa.gov/toxics-release-inventorv-tri-program/tri-data-and-tools
WIL Research (WIL Research Labs). (2001). An inhalation two-generation reproductive toxicity study of
1-bromopropane in rats. (Study No. WIL-380001). Ashland, OH.
Yalkowsky, SH; He. Y; Jain, P. (2010). Handbook Of Aqueous Solubility Data (2nd ed.). Boca Raton, FL:
CRC Press. http://dx.doi.org/10.1201/EBK1439802458
Young. ML. (2012). Pre-spotting step toward better cleaning. Available online at
https://americandrycleaner.com/articles/pre-spotting-step-toward-better-cleaning
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APPENDICES
Appendix A REGULATORY HISTORY
A.1 Federal Laws and Regulations
Table_Apx A-l. Federal Laws and Regulations
Statutes/Regulations
Description of Authority/Regulation
Description of Regulation
US EPA Regulations
Toxic Substances
Control Act (TSCA) -
Section 6(b)
EPA is directed to identify and begin
risk evaluations on 10 chemical
substances drawn from the 2014
update of the TSCA Work Plan for
Chemical Assessments.
1-BP is on the initial list of
chemicals to be evaluated
for unreasonable risk
underTSCA (81 FR 91927,
December 19, 2016)
Toxic Substances
Control Act (TSCA) -
Section 8(a)
The TSCA section 8(a) Chemical Data
Reporting (CDR) Rule requires
manufacturers (including importers) to
give EPA basic exposure-related
information on the types, quantities
and uses of chemical substances
produced domestically and imported
into the US.
1-BP manufacturing,
importing, processing,
and use information is
reported under the
Chemical Data Reporting
(CDR) rule (76 FR 50816,
August 16, 2011).
Toxic Substances
Control Act (TSCA) -
Section 8(b)
EPA must compile, keep current, and
publish a list (the TSCA Inventory) of
each chemical substance
manufactured, processed, or imported
in the United States.
1-BP was on the initial
TSCA Inventory and
therefore was not subject
to EPA's new chemicals
review process (60 FR
16309, March 29, 1995).
Toxic Substances
Control Act (TSCA) -
Section 8(e)
Manufacturers (including importers),
processors, and distributors must
immediately notify EPA if they obtain
information that supports the
conclusion that a chemical substance
or mixture presents a substantial risk
of injury to health or the environment.
Eleven notifications of
substantial risk (Section
8(e)) received before
2001 (US EPA, ChemView.
Accessed April 13, 2017).
Toxic Substances
Control Act (TSCA) -
Section 4
Provides EPA with authority to issue
rules and orders requiring
manufacturers (including importers)
and processors to test chemical
substances and mixtures.
One submission from a
test rule (Section 4)
received in 1981 (US EPA,
ChemView. Accessed April
13, 2017).
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Statutes/Regulations
Description of Authority/Regulation
Description of Regulation
Emergency Planning
and Community Right-
To-Know Act (EPCRA) -
Section 313
Requires annual reporting from facilities
in specific industry sectors that employ
10 or more full time equivalent
employees and that manufacture,
process, or otherwise use a Toxics
Release Inventory (TRI)-listed chemical
in quantities above threshold levels.
1-BP is a listed substance
subject to reporting
requirements under 40
CFR 372.65 effective as of
January 1, 2016, with
reporting due July 1, 2017
(80 FR 72906, November
23, 2015).
Clean Air Act (CAA) -
Section 112(b)
This section lists 189 Hazardous Air
Pollutants (HAPs) that must be
addressed by EPA and includes
authority for EPA to add or delete
pollutants. EPA may, by rule, add
pollutants that present, or may present,
a threat of adverse human health
effects or adverse environmental
effects.
EPA received petitions
from the Halogenated
Solvent Industry Alliance
and the New York State
Department of
Environmental
Conservation to list 1-BP as
a hazardous air pollutant
(HAP) under section
112(b)(1) of the Clean Air
Act (80 FR 6676, February
6, 2015). On January 9,
2017, EPA published a
draft notice on the rational
for granting the petitions
to add 1-BP to the list of
hazardous air pollutants.
Comments are due June 8,
2017 (82 FR 2354, January
9, 2017). Since 1-BP is not
a HAP, currently, there are
no National Emissions
Standards for Hazardous
Air Pollutants (NESHAPs)
that apply to the life cycle.
Clean Air Act (CAA) -
Section 183(e)
Section 183(e) requires EPA to list the
categories of consumer and commercial
products that account for at least 80
percent of all VOC emissions in areas
that violate the National Ambient Air
Quality Standards (NAAQS) for ozone
and to issue standards for these
categories that require "best available
controls." In lieu of regulations, EPA
may issue control techniques guidelines
if the guidelines are determined to be
1-BP is listed under the
National Volatile Organic
Compound Emission
Standards for Aerosol
Coatings (40 CFR part 59,
subpart E). 1-BP has a
reactivity factor of 0.35 g
03/g VOC.
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Statutes/Regulations
Description of Authority/Regulation
Description of Regulation
substantially as effective as
regulations.
Clean Air Act (CAA) -
Section 612
Under Section 612 of the Clean Air Act
(CAA), EPA's Significant New
Alternatives Policy (SNAP) program
reviews substitutes for ozone depleting
substances within a comparative risk
framework. EPA publishes lists of
acceptable and unacceptable
alternatives. A determination that an
alternative is unacceptable, or
acceptable only with conditions, is
made through rulemaking.
Under EPA's SNAP
program, EPA evaluated 1-
BP as an acceptable
substitute for ozone-
depleting substances. In
2007, EPA listed 1-BP as an
acceptable substitute for
chlorofluorocarbon (CFC)-
113 and methyl
chloroform in the solvent
and cleaning sector for
metals cleaning,
electronics cleaning, and
precision cleaning. EPA
recommended the use of
personal protective
equipment, including
chemical goggles, flexible
laminate protective gloves
and chemical-resistant
clothing (72 FR 30142, May
30, 2007). In 2007, the
Agency also proposed to
list 1-BP as an
unacceptable substitute
for CFC-113,
hydrochlorofluorocarbon
(HCFC)- 114b and methyl
chloroform when used in
adhesives or in aerosol
solvents; and in the
coatings end use (subject
to use conditions) (72 FR
30168, May 30, 2007). The
proposed rule has not
been finalized by the
Agency. The rule identifies
1-BP as acceptable and
unacceptable substitute
for ozone-depleting
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Statutes/Regulations
Description of Authority/Regulation
Description of Regulation
substances in several
sectors.
Other Federal Regulations
Occupational Safety
and Health Act (OSHA)
Requires employers to provide their
workers with a place of employment
free from recognized hazards to safety
and health, such as exposure to toxic
chemicals, excessive noise levels,
mechanical dangers, heat or cold stress,
or unsanitary conditions.
Under the Act, OSHA can issue
occupational safety and health
standards including such provisions as
Permissible Exposure Limits (PELs),
exposure monitoring, engineering and
administrative control measures, and
respiratory protection.
OSHA has not issued a PEL
for 1-BP.
OSHA and the National
Institute for Occupational
Safety and Health (NIOSH)
issued a Hazard Alert
regarding 1-BP (OSHA-
NIOSH, 2013) providing
information regarding
health effects, how
workers are exposed, how
to control the exposures
and how OSHA and NIOSH
can help.
Department of Energy
(DOE)
The Atomic Energy Act authorizes DOE
to regulate the health and safety of its
contractor employees.
10 CFR 851.23, Worker
Safety and Health
Program, requires the use
of the 2005 ACGIH TLVs if
they are more protective
than the OSHA PEL. The
2005 TLV for 1-BP is 10
ppm (8hrTime Weighted
Average).
A. 2 State Laws and Regulations
Table_Apx A-2. State Laws and Regulations
State Actions
Description of Action
State Air Regulations
Allowable Ambient Levels
• Rhode Island (Air Pollution Regulation No. 22)
• New Hampshire (Env-A 1400: Regulated Toxic Air
Pollutants)
Chemicals of High Concern
Massachusetts designated 1-BP as a higher hazard
substance requiring reporting starting in 2016 (301
CMR 41.00).
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State Actions
Description of Action
Minnesota listed 1-BP as chemical of high concern to
children (Minnesota Statutes 116.9401 to 116.9407).
State Permissible Exposure Limits
California PEL: 5 ppm as an 8-hr-time-weighted
average (TWA) (California Code of Regulations, title 8,
section 5155).
State Right-to-Know Acts
New Jersey (42 N.J.R. 1709(a)), Pennsylvania (Chapter
323. Hazardous Substance List).
In California, 1-BP was added to proposition 65 list in
December 2004 due to developmental, female and
male, toxicity; and in 2016 due to cancer. (Cal. Code
Regs, title 27, section 27001).
Other
1-BP is listed as a Candidate Chemical under
California's Safer Consumer Products Program (Health
and Safety Code sections 25252 and 25253).
California also issued a Health Hazard Alert for 1-BP
(Hazard Evaluation System and Information Service,
2016).
A.3 International Laws and Regulations
Table_Apx A-3. Regulatory Actions by other Governments and Tribes
Country /Organization
Requirements and Restrictions
European Union
In 2012, 1-BP was listed on the Candidate list as a Substance of Very High
Concern (SVHC) under regulation (EC) No 1907/2006 - REACH (Registration,
Evaluation, Authorization and Restriction of Chemicals due to its reproductive
toxicity (category IB).
In July 2015, 1-BP was recommended for inclusion in Annex XIV of REACH
(Authorisation List) (European Chemicals Agency (ECHA) database. Accessed
April 18, 2017).
Australia
1-BP was assessed under Environment Tier II of the Inventory Multi-tiered
Assessment and Prioritisation (IMAP) (National Industrial Chemicals
Notification and Assessment Scheme, 2017, Human Health Tier II Assessment
for Propane, 1-bromo-. Accessed April, 18 2017).
Japan
1-BP is regulated in Japan under the following legislation:
• Act on the Evaluation of Chemical Substances and Regulation of Their
Manufacture, etc. (Chemical Substances Control Law; CSCL)
• Act on Confirmation, etc. of Release Amounts of Specific Chemical Substances in
the Environment and Promotion of Improvements to the Management Thereof
• Industrial Safety and Health Act (ISHA)
• Air Pollution Control Law
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Country /Organization
Requirements and Restrictions
(National Institute of Technology and Evaluation (NITE) Chemical Risk
Information Platform (CHIRP). Accessed April 13, 2017).
Belgium, Canada,
Finland, Japan, Poland,
South Korea and
Spain
Occupational exposure limits for 1-BP. (GESTIS International limit values for
chemical agents (Occupational exposure limits, OELs) database. Accessed
April 18, 2017).
Basel Convention
Halogenated organic solvents (Y41) are listed as a category of waste under
the Basel Convention_- Annex 1. Although the United States is not currently a
party to the Basel Convention, this treaty still affects U.S. importers and
exporters.
OECD Control of
Transboundary
Movements of Wastes
Destined for Recovery
Operations
Halogenated organic solvents (A3150) are listed as a category of waste
subject to The Amber Control Procedure under Council Decision C (2001)
107/Final.
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Appendix B PROCESS, RELEASE AND OCCUPATIONAL EXPOSURE
INFORMATION
This appendix provides information and data found in preliminary data gathering for 1-BP.
B.l Process Information
Process-related information potentially relevant to the risk evaluation may include process diagrams,
descriptions and equipment. Such information may inform potential release sources and worker
exposure activities. EPA will consider this information in combination with available monitoring data
and estimation methods and models, as appropriate, to quantity occupational exposure and releases
for the various conditions of use in the risk evaluation. Most of the process-related information
provided below, especially descriptions pertaining to IBP use in degreasing (vapor, cold and aerosol),
spray adhesive, dry cleaning and spot cleaning, has been previously compiled, described and peer
reviewed in EPA's 2016 Draft Risk Assessment (U.S. EPA. 2016b).
B.l.l Manufacture (Including Import)
B.l.1.1 Domestic Manufacture
1-BP is produced by reacting n-propyl alcohol with hydrogen bromide and then removing the excess
water that forms in the process (| 13). The reaction product may then be distilled, neutralized
with sodium hydrogen carbonate, packaged and stored (Ichihara et al., 2004).
B.l.1.2 Import
EPA expects that imported chemicals are often stored in warehouses prior to distribution for further
processing and use. In some cases, the chemicals may be repackaged into differently sized containers,
depending on customer demand, and QC samples may be taken for analyses.
B.l.2 Processing and Distribution
Based on the reported industrial processing operations in the 2016 CDR. 1-BP may be incorporated into
a variety of formulations, products and articles, or used industrially as a chemical intermediate (U.S.
EPA. 2016a). Some industrial or commercial products may also be repackaged into appropriately-sized
containers to meet specific customer demands (U.S. EPA. 2016a).
B.1.2.1 Processing as a Reactant
Processing as a reactant or intermediate is the use of 1-BP as a feedstock in the production of another
chemical via a chemical reaction in which 1-BP is consumed to form the product. EPA has not identified
specific information for the processing of 1-BP as a reactant.
B.l.2.2 Incorporated into Formulation, Mixture or Reaction Product
Incorporation into a formulation, mixture or reaction product refers to the process of mixing or
blending of several raw materials to obtain a product or mixture (e.g., adhesives and sealants). EPA
has not identified 1-BP specific formulation processes.
B.l.2.3 Incorporated into Article
Incorporation into an article typically refers to a process in which a chemical becomes an integral
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component of an article that is distributed for industrial, trade, or consumer use. Exact process
operations involved in the incorporation of 1-BP are dependent on the article. EPA will further
investigate the potential use of 1-BP in this type of process during the risk evaluation.
B.1.2.4 Repackaging
Typically, repackaging sites receive the chemical in bulk containers and transfer the chemical from the
bulk container into another smaller container in preparation for distribution in commerce. Based on
EPA's knowledge of the chemical industry, worker activities at repackaging sites may involve manually
unloading 1-BP from bulk containers into the smaller containers for distribution or
connecting/disconnecting transfer lines used to transfer 1-BP product between containers and
analyzing QC samples. EPA will further investigate the potential use of 1-BP in this type of process
during the risk evaluation.
B.1.2.5 Recycling
A general description of waste solvent recovery processes was identified. Waste solvents are
generated when it becomes contaminated with suspended and dissolved solids, organics, water, or
other substance (U.S. EPA. 1980). Waste solvents can be restored to a condition that permits reuse via
solvent reclamation/recycling (U.S. EPA. 1980). The recovery process involves an initial vapor recovery
(e.g., condensation, adsorption and absorption) or mechanical separation (e.g., decanting, filtering,
draining, setline and centrifuging) step followed by distillation, purification and final packaging (U.S.
EPA. 1980).
B.1.3 Uses
In this scope document, EPA has grouped uses based on CDR categories and identified examples within
these categories as subcategories of use. Note that some subcategories of use may be grouped under
multiple CDR categories. The differences between these uses will be further investigated during risk
evaluation.
B.1.3.1 Solvents for Cleaning and Degreasing
Solvents for Cleaning and Degreasing category encompasses chemical substances used to dissolve oils,
greases and similar materials from a variety of substrates including metal surfaces, glassware and
textiles. This category includes the use of 1-BP in vapor degreasing, cold cleaning and in industrial and
commercial aerosol degreasing products.
Vapor Degreasing
Vapor degreasing is a process used to remove dirt, grease and surface contaminants in a variety of
metal cleaning industries. 1-BP is often used to replace chlorinated solvents in vapor degreasing
applications. Vapor degreasing may take place in batches or as part of an in-line (i.e., continuous)
system. In batch machines, each load (parts or baskets of parts) is loaded into the machine after the
previous load is completed. With in-line systems, parts are continuously loaded into and through the
vapor degreasing equipment as well as the subsequent drying steps. Vapor degreasing equipment can
generally be categorized into one of the three categories: (1) batch vapor degreasers, (2) conveyorized
vapor degreasers and (3) web vapor degreasers.
Each category of vapor degreaser is described below.
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Batch Vapor Degreasers
• Open top vapor degreasers (OTVD): In OTVDs, a vapor cleaning zone is created by heating the
liquid solvent in the OTVD causing it to volatilize. Workers manually load or unload fabricated
parts directly into or out of the vapor cleaning zone. The tank usually has chillers along the side
of the tank to prevent losses of the solvent to the air. However, these chillers are not able to
eliminate emissions, and throughout the degreasing process, significant air emissions of the
solvent can occur. These air emissions can cause issues with both worker health and safety as
well as environmental issues. Additionally, the cost of replacing solvent lost to emissions can be
expensive (NEWMOA. 2001). Figure_Apx B-l illustrates a standard OTVD. The use of 1-BP in
OTVD has been previously described in EPA's 2016 Draft Risk Assessment (U.S. EPA. 2016b).
o
8;
o
-CH
Vapor Zone
]
Condensing Coils
Water Jacket
~ /Water Separator
Boiling sump-
T
Heat Source
Figure_Apx B-l. Open Top Vapor Degreaser
• OTVD with enclosure: OTVDs with enclosures operate the same as standard OTVDs except that
the OTVD is enclosed on all sides during degreasing. The enclosure is opened and closed to add
or remove parts to/from the machine, and solvent is exposed to the air when the cover is open.
Enclosed OTVDs may be vented directly to the atmosphere or first vented to an external carbon
filter and then to the atmosphere (U.S. EPA. 2004). Figure_Apx B-2 illustrates an OTVD with an
enclosure. The dotted lines in Figure_Apx B-2 represent the optional carbon filter that may or
may not be used with an enclosed OTVD.
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J1
Loading/
unloading
lock
Boiling su
Heat Sou
np-
ce-
-•» Carbon Filter
C
Vapor Zone
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D
Wate
wWa
Condensing Colls
Jacket
er Separator
Figure_Apx B-2. Open Top Vapor Degreaser with Enclosure
• Closed-loop degreasing system (airtight): In closed-loop degreasers, parts are placed into a
basket, which is then placed into an airtight work chamber. The door is closed and solvent
vapors are sprayed onto the parts, Solvent can also be introduced to the parts as a liquid spray
or liquid immersion. When cleaning is complete, vapors are exhausted from the chamber and
circulated over a cooling coil where the vapors are condensed and recovered. The parts are
dried by forced hot air. Air is circulated through the chamber and residual solvent vapors are
captured by carbon adsorption. The door is opened when the residual solvent vapor
concentration has reached a specified level (Kanegsberg and Kanegsberg. 2011). Figure_Apx B-3
illustrates a standard closed-loop vapor degreasing system.
| Vent
I
Solvent Abatement Loop
Distillation
Solvent Tank(s)
Refrigeration
2
Working Chamber
Workload
Solvent Sump
Electric Heat
Figure_Apx B-3. Closed-Loop/Vacuum Vapor Degreaser
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• Airless degreasing system (vacuum drying): Airless degreasing systems are also sealed, closed-
loop systems, but remove air at some point of the degreasing process. Removing air typically
takes the form of drawing vacuum, but could also include purging air with nitrogen at some
point of the process (in contrast to drawing vacuum, a nitrogen purge operates at a slightly
positive pressure). In airless degreasing systems with vacuum drying only, the cleaning stage
works similarly as with the airtight closed-loop degreaser. However, a vacuum is generated
during the drying stage, typically below 5 torr (5 mmHg). The vacuum dries the parts and a
vapor recovery system captures the vapors (Kanegsberg and Kanegsberg, 2011; NEWMOA,
2001: U.S. EPA. 2001).
• Airless vacuum-to-vacuum degreasing system: Airless vacuum-to-vacuum degreasers are true
"airless" systems because the entire cycle is operated under vacuum. Typically, parts are placed
into the chamber, the chamber sealed, and then vacuum drawn within the chamber. The typical
solvent cleaning process is a hot solvent vapor spray. The introduction of vapors in the vacuum
chamber raises the pressure in the chamber. The parts are dried by again drawing vacuum in
the chamber. Solvent vapors are recovered through compression and cooling. An air purge then
purges residual vapors over an optional carbon adsorber and through a vent. Air is then
introduced in the chamber to return the chamber to atmospheric pressure before the chamber
is opened (Durkee. 2014: NEWMOA. 2001).
The general design of vacuum vapor degreasers and airless vacuum degreasers is similar as illustrated
in Figure_Apx B-3 for closed-loop systems except that the work chamber is under vacuum during
various stages of the cleaning process.
Conveyorized Vapor Degreasers
Conveyorized vapor degreasing systems are solvent cleaning machines that use an automated parts
handling system, typically a conveyor, to automatically provide a continuous supply of parts to be
cleaned. Conveyorized degreasing systems are usually fully enclosed except for the conveyor inlet and
outlet portals. Conveyorized degreasers are likely used in similar shop types as batch vapor degreasers
except for repair shops, where the number of parts being cleaned is likely not large enough to warrant
the use of a conveyorized system.
There are seven major types of conveyorized degreasers (U.S. EPA. 1977):
• Monorail degreasers: Monorail degreasing systems are typically used when parts are already
being transported throughout the manufacturing areas by a conveyor conveyor (U.S. EPA.
1977). They use a straight-line conveyor to transport parts into and out of the cleaning zone.
The parts may enter one side and exit and the other or may make a 180° turn and exit through
a tunnel parallel to the entrance (U.S. EPA. 1977).
• Cross-rod degreasers: Cross-rod degreasing systems utilize two parallel chains connected by a
rod that support the parts throughout the cleaning process. The parts are usually loaded into
perforated baskets or cylinders and then transported through the machine by the chain support
system. The baskets and cylinders are typically manually loaded and unloaded (U.S. EPA. 1977).
Cylinders are used for small parts or parts that need enhanced solvent drainage because of
crevices and cavities. The cylinders allow the parts to be tumbled during cleaning and drying
and thus increase cleaning and drying efficiency.
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• Vibra degreasers: In vibra degreasing systems, parts are fed by conveyor through a chute that
leads to a pan flooded with solvent in the cleaning zone. The pan and the connected spiral
elevator are continuously vibrated throughout the process, causing the parts to move from the
pan and up a spiral elevator to the exit chute. As the parts travel up the elevator, the solvent
condenses and the parts are dried before exiting the machine (U.S. EPA. 1977).
• Ferris wheel degreasers: Ferris wheel degreasing systems are generally the smallest of all the
conveyorized degreasers (U.S. EPA. 1977). In these systems, parts are manually loaded into
perforated baskets or cylinders and then rotated vertically through the cleaning zone and back
out.
• Belt degreasers: Belt degreasing systems (similar to strip degreasers; see next bullet) are used
when simple and rapid loading and unloading of parts is desired (U.S. EPA. 1977). Parts are
loaded onto a mesh conveyor belt that transports them through the cleaning zone and out the
other side.
• Strip degreasers: Strip degreasing systems operate similar to belt degreasers except that the
belt itself is being cleaned rather than parts being loaded onto the belt for cleaning.
• Circuit board cleaners: Circuit board degreasers use any of the conveyorized designs. However,
in circuit board degreasing, parts are cleaned in three different steps due to the manufacturing
processes involved in circuit board production (U.S. EPA. 1977).
Continuous Web Vapor Degreasers
Continuous web cleaning machines differ from typical conveyorized degreasers in that they are
specifically designed for cleaning parts that are coiled or on spools such as films, wires and metal strips
(Kanegsberg and Kanegsberg, 2011; U.S. EPA. 2006b). In continuous web degreasers, parts are uncoiled
and loaded onto rollers that transport the parts through the cleaning and drying zones at speeds
>11 feet/minute (U.S. EPA. 2006b). The parts are then recoiled or cut after exiting the cleaning
machine (Kanegsberg and Kanegsberg. 2011; U.S. EPA. 2006b).
Cold Cleaning
1-BP can also be used as a solvent in cold cleaners, which are non-boiling solvent degreasing units. Cold
cleaning operations include spraying, brushing, flushing and immersion. In a typical batch-loaded,
maintenance cold cleaner, dirty parts are cleaned manually by spraying and then soaking in the tank.
After cleaning, the parts are either suspended over the tank to drain or are placed on an external rack
that routes the drained solvent back into the cleaner. Batch manufacturing cold cleaners could vary
widely, but have two basic equipment designs: the simple spray sink and the dip tank. The dip tank
design typically provides better cleaning through immersion, and often involves an immersion tank
equipped with agitation (U.S. EPA. 1981). Emissions from batch cold cleaning machines typically result
from (1) evaporation of the solvent from the solvent-to-air interface, (2) "carry out" of excess solvent
on cleaned parts and (3) evaporative losses of the solvent during filling and draining of the machine
(U.S. EPA. 2006b).
Aerosol Degreasing
Aerosol degreasing is a process that uses an aerosolized solvent spray, typically applied from a
pressurized can, to remove residual contaminants from fabricated parts. The aerosol droplets bead up
on the fabricated part and then drip off, carrying away any contaminants and leaving behind a clean
surface. One example of commercial setting that uses aerosol degreasing operation is repair shops,
where service items are cleaned to remove any contaminants that would otherwise compromise the
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service item's operation. Internal components may be cleaned in place or removed from the service
item, cleaned, and then re-installed once dry (U.S. EPA. 2014).
B.l.3.2 Adhesives and Sealants
1-BP is a component of spray adhesive. In foam cushion manufacturing, workers use a spray gun to
spray-apply adhesive containing 1-BP onto flexible foam surfaces. Adhesive spraying typically occurs
either on an open top workbench with side panels that may have some local ventilation, or in an open
workspace with general room ventilation. After the adhesive is applied, workers hand-press the flexible
foam pieces together to assemble the cushions.
B.l.3.3 Agricultural Products (Non-pesticidal)
This CDR category includes chemicals used to improve crop productivity and quality, including
fertilizers, additives, colorants, application aids, pH adjusters, moisture retention agents, soil
conditioners and seed coatings (U.S. EPA. 2016a). The product category does not include any chemical
that is manufactured, processed, or distributed in commerce for use as a pesticide as defined by the
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) (U.S. EPA. 2016a). The company reported
that the determination of whether this product was for commercial or consumer uses was "not known
or reasonably ascertainable." EPA has not identified further process information specific to use of IBP
in agricultural products.
B.1.3.4 Cleaning and Furniture Care Products
1-BP can be used as a solvent in dry cleaning machines and 1-BP formulations such as DrySolv® are
often marketed as "drop-in" replacements for PERC, which indicates that they can be used in third-
generation or higher PERC equipment (TURI, 2012). Dry cleaners who opt to use 1-BP can either
convert existing PERC machines or purchase a new dry cleaning machine specifically designed for 1-BP.
To convert existing PERC machines to use 1-BP, machine settings and components must be changed to
prevent machine overheating and solvent leaks (Blando et al., 2010). 1-BP is known to damage rubber
gaskets and seals. It can also degrade cast aluminum, which is sometimes used on equipment doors
and other dry cleaning machine components. In addition, 1-BP is not compatible with polyurethane
and silicone (TURI. 2012).
In addition, 1-BP is found in products used to spot clean garments. Spot cleaning products can be
applied to the garment either before or after the garment is dry cleaned. Spot cleaning occurs on a
spotting board and spotting agent can be applied from squeeze bottles, hand-held spray bottles or
even from spray guns connected to pressurized tanks. Once applied, the dry cleaner may come into
further contact with the 1-BP if using a brush, spatula, pressurized air or steam or their fingers to
scrape or flush away the stain (Young. 2012; NIOSH. 1997).
B.l.3.5 Other Uses
Based on products identified in EPA's preliminary data gathering and information received in public
comments, a variety of other uses may exist for 1-BP including in lubricants, insulation, mold release
products, refrigerants, adhesive accelerants, asphalt extraction, and temperature indicators for
laboratory applications [see Preliminary Information on Manufacturing, Processing, Distribution, Use,
and Disposal: 1-Bromopropane, EPA~HQ~OPPT~2016~0741~00Q3 (U.S. EPA. 2017a)l. EPA has not
identified any process-specific information to further refine the use of 1-BP in these applications at this
time and more information on these uses will be gathered through expanded literature searches
during risk evaluation.
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B.1.4 Disposal
Disposal of a chemical should take into consideration the chemical's potential impact on air quality,
migration to groundwater, effect on biological species, and disposal regulations (if any) (ATSDR. 2016).
Due to the high volatility of 1-BP, releases to the atmosphere are expected to be the primary release
route of 1-BP (ATSDR. 2016). Currently, 1-BP is not regulated under federal regulations as a hazardous
waste (U.S. EPA. 2017a). However, 1-BP may be disposed of as a hazardous waste if it is present in or
co-mingled with solvent mixtures that are RCRA regulated substances. EPA has not identified further
process information specific to disposal of 1-BP at this time, but will review TRI data submitted for
1-BP, as it becomes available, for information on how wastes containing 1-BP are disposed.
B.2 Occupational Exposure Data
EPA presents below an example of occupational exposure-related information from the preliminary
data gathering. EPA will consider this information and data in combination with other data and
methods for use in the risk evaluation.
Table_Apx B-l summarizes the industry sectors with 1-BP OSHA CEHD data (OSHA. 2017).
Table_Apx B-l. Summary of Industry Sectors with 1-BP Personal Monitoring Air Samples Obtained
:rom OSHA Inspections Conducted Between 2013 and 2016
North American
Industry Classification
System (NAICS)
NAICS Description
336412
Aircraft engine and engine parts manufacturing
448190
Other clothing stores
333517
Machine tool manufacturing
334418
Printed circuit assembly
331210
Iron and steel pipe and tube manufacturing from purchased steel
336413
Other aircraft parts and auxiliary equipment manufacturing
332813
Electroplating, plating, polishing, anodizing and coloring
323113
Commercial screen printing
332913
Plumbing fixture fitting and trim manufacturing
332721
Precision turned product manufacturing
333911
Pump and pumping equipment manufacturing
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