Environmental Risk Assessment for Formaldehyde CASRN 50-00-0


A EPA

EPA Document #EPA-740-R-24-014
December 2024

United States	Office of Chemical Safety and

Environmental Protection Agency	Pollution Prevention

Environmental Risk Assessment for Formaldehyde

CASRN 50-00-0

o

December 2024

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TABLE OF CONTENTS

EXECUTIVE SUMMARY	4

1	INTRODUCTION	6

1.1	Background	6

1.2	Risk Evaluation Scope	6

1.2.1	Life Cycle and Production	8

1.2.2	Conditions of Use	10

1.3	Changes between Draft and the Revised Assessment	10

1.4	Chemistry, Fate, and Transport Assessment	10

1.5	Environmental Release Assessment	12

1.6	Environmental Exposure Assessment	14

1.7	Transformation Products in Environmental Media	15

1.8	Problem Formulation for Environmental Pathways	15

2	RISK ASSESSMENT APPROACH	16

2.1	Ambient Air	16

2.2	Hazard Summary	18

2.2.1	Terrestrial Vertebrate Toxicity	19

2.2.2	Plant Toxicity	19

2.3	Summary of Environmental Risk Assessment	19

2.3.1	Terrestrial Vertebrate Risk Assessment	20

2.3.2	Plant Risk Assessment	20

2.3.3	Overall Confidence and Remaining Uncertainties in Environmental Risk Assessment	21

REFERENCES	22

APPENDICES	24

Appendix A ABBREVIATIONS AND ACRONYMS	24

Appendix B LIST OF DOCUMENTS AND SUPPLEMENTAL FILES	25

Appendix C CONSIDERATION OF WATER DEPOSITION FROM AIR	27

LIST OF TABLES	

Table 1-1. Physical and Chemical Properties of Formaldehyde and Select Transformation Products .... 11
Table 2-1. Summary of the Most Sensitive Toxicity Endpoints for Terrestrial Organisms Exposed to

Formaldehyde in Air	19

Table 2-2. Comparison of Formaldehyde Air Concentrations and Terrestrial Organism Toxicity	20

LIST OF FIGURES	

Figure 1-1. Risk Evaluation Document Summary Map	7

Figure 1-2. Formaldehyde Lifecycle Diagram	9

Figure 1-3. Chemical Equilibria for Formaldehyde in Aqueous Solutions	11

Figure 2-1. Distributions of Ambient Air Formaldehyde Concentration Based on Monitoring Data and

Model Data	18

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LIST OF APPENDIX FIGURES	

Figure Apx C-l. Estimated Water Concentration from Water Deposition from Air Using Henry's Law
Constant	27

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Key Points: Environmental Risk Assessment for Formaldehyde

This assessment considers formaldehyde Toxic Substances Control Act (TSCA) conditions of use
(COUs), physical and chemical properties, environmental release data, as well as environmental
modeling and monitoring data of formaldehyde and concludes there is

• No risk to the environment;

• No risk to aquatic organisms as formaldehyde does not persist in water and exposure is not
expected;

• No risk to terrestrial organisms through soil exposure as formaldehyde does not persist in or
on land and exposure is not expected;

• No risk to terrestrial mammals through inhalation as air concentrations are at least an order of
magnitude lower than the most sensitive toxicity value;

• No risk to other terrestrial taxa, even though no inhalation toxicity data are available for other
terrestrial species, as there is at least an order of magnitude difference in the toxicity and
exposure for mammals; and

• No risk to plants from formaldehyde exposures in ambient air because air concentrations are 7
times lower than the most sensitive toxicity value.

EXECUTIVE SUMMARY

Formaldehyde is manufactured for a wide variety of commercial and consumer products. It is also a
naturally occurring aldehyde produced during combustion, decomposition of organic matter, and as a
byproduct of metabolism in living organisms.

EPA reviewed reasonably available information as part of the scope and development of this
environmental risk assessment for formaldehyde. Specifically, the Agency reviewed the environmental
fate and transport of formaldehyde (U.S. EPA 2024b I environmental releases (U.S. EPA 2024g) and
environmental exposures (U.S. EPA 2024e). as well as reasonably available environmental hazard data
(U.S. EPA. 2024f) for aquatic and terrestrial organisms. These evaluations provide the foundation for
comparing estimated formaldehyde exposures to environmental hazard data for determining potential
risk. Details on each of these topics are provided in the respective modules included as attachments to
this risk assessment and are summarized below.

EPA assessed formaldehyde in various media (air, water, soil). In some cases, the Agency further
characterized transformation of formaldehyde to other chemical species to explain how the chemical
changes in the environment. Comparative toxicity data indicate formaldehyde toxicity is protective of
transformation product toxicity in aquatic organisms.

Environmental fate and transport data indicate formaldehyde will not persist in water due to its highly
reactive nature (U.S. EPA 2024b. g). Specifically, formaldehyde quickly hydrates in water to methylene
glycol and can further transform to other oligomers that are structurally and chemically dissimilar to
both formaldehyde and methylene glycol; that is, transformation products do not behave similarly in
water (Bover et al.. 2013). Although transformation products were not evaluated for environmental risk,
comparative toxicity data for formaldehyde and transformation products are provided in the
Environmental Hazard module of this risk assessment (U.S. EPA. 2024f) and demonstrate that
formaldehyde toxicity is protective of transformation product toxicity to aquatic organisms.

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Furthermore, reported releases of formaldehyde waste to water form a smaller component of the total
reported releases to the environment compared to other media such as air, they are therefore less
common (U.S. EPA. 2024a).

Surface water monitoring data indicate formaldehyde is below detection limits in most samples (U.S.
EPA. 2024e). According to the Water Quality Portal (WQP), 866 formaldehyde monitoring activities
were conducted between 1969 and 2022 (U.S. EPA et al.. 2022). Eighty-nine percent of monitoring
samples reported no detectable formaldehyde. The remaining 11 percent of samples reported
formaldehyde concentrations were mostly from sampling events before 1975 and their quality could not
be verified (U.S. EPA et al.. 2022). Water monitoring data for formaldehyde may be informative for
general context but are not associated either temporally or spatially with known industrial releases to
water. Considering these lines of evidence, EPA does not expect formaldehyde will persist in water and
therefore concludes there is no risk to aquatic organisms via surface water due to low exposure via the
water pathway.

Environmental fate and transport data also indicate formaldehyde will not persist on land or be available
for dietary uptake (U.S. EPA. 2024b). Formaldehyde will rapidly react with proton donors on particle
surfaces and transform to numerous other substances that cannot be effectively characterized. Similar to
surface water, formaldehyde will rapidly hydrate in groundwater and can further transform to oligomers
of various chain length, which will continue to unpredictably react with other chemical substances.
These oligomers will generally have different toxicity profiles but are expected to be less toxic than
formaldehyde. The predominant environmental release of formaldehyde to land is disposal via
underground injection (U.S. EPA. 2024g). Additionally, formaldehyde does not bioaccumulate and is
unlikely to be available via dietary consumption. Considering these lines of evidence, EPA does not
expect formaldehyde will persist in or on land and therefore concludes there is no risk to terrestrial
organisms via the land pathway because of low exposures.

Environmental fate and transport data indicate formaldehyde can persist in air—although formaldehyde
is subject to photolysis or chemical reactions in the presence of free-radicals or other components in the
ambient air (including moisture) (U.S. EPA. 2024b). In direct sunlight, the half-life of formaldehyde is
estimated to be between 1.4 and 4 hours. This persistence can be longer if direct sunlight is not present
or if releases are at night. A large portion of reported environmental releases in multiple databases were
also identified to the ambient air (U.S. EPA. 2024g). EPA similarly identified ambient monitoring data
supporting the persistence of formaldehyde in ambient air, even though the source of monitored
formaldehyde may be due to several sources, including industrial releases from TSCA COUs, biogenic
sources1, or secondary formation from other chemical substances that cannot be determined (U.S. EPA.
2024e). Considering these lines of evidence, EPA expects formaldehyde will be present in ambient air
and could result in short, transient exposures to terrestrial organisms. However, attributing these
terrestrial exposures to a TSCA-specific COU is difficult due to multiple sources of formaldehyde in
ambient air (industrial, biogenic, secondary formation, etc.). EPA evaluated potential environmental
exposures of terrestrial organisms to formaldehyde from the ambient air. The Agency's analysis
considers the toxicity of formaldehyde exposure to both plants (via air exposure) and terrestrial
vertebrates (via inhalation) and compares those to modeled and measured ambient air concentrations.
The most sensitive reported toxicity values reported were approximately an order of magnitude higher
than the highest measured or modeled formaldehyde concentration in air indicating no risk to plants and
terrestrial vertebrates relative to the most sensitive toxicity endpoints.

1 Produced by living organisms

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1 INTRODUCTION

1.1 Background

Formaldehyde is a gas that is distributed in solution as formalin or in a solid as paraformaldehyde. It is
produced industrially and may be used in a wide variety of commercial and consumer products,
including textiles, foam bedding/seating, semiconductors, resins, glues, composite wood products,
paints, coatings, plastics, rubber, construction materials (including insulation and roofing), furniture,
toys, and in various adhesives and sealants. Formaldehyde is also a naturally occurring aldehyde
produced during combustion, the decomposition of organic matter, and is produced in living things
through metabolism. Thus, formaldehyde is ubiquitous in indoor and ambient air environments.

Formaldehyde is a high priority chemical undergoing the Toxic Substances Control Act (TSCA) risk
evaluation process. There are many anthropogenic sources of formaldehyde ranging from agricultural
products to rubber matting. Not all are relevant for this risk assessment as it is a TSCA-specific
document that serves to support risk management needs by EPA's Office of Pollution Prevention and
Toxics (OPPT) and is one of many documents comprising the Formaldehyde Risk Evaluation (see
Figure 1-1) (Docket ID: EPA-HQ-QPPT-2018-0438).

1.2 Risk Evaluation Scope

The TSCA risk evaluation of formaldehyde comprises several human health and environmental
assessment modules and two risk assessment documents—the environmental risk assessment and the
human health risk assessment. A basic diagram showing the layout of these assessments and the
relationships is provided in Figure 1-1. This EPA Office of Pollution Prevention and Toxics (OPPT)
environmental risk assessment is shaded blue. In some cases, modular assessments were completed
jointly under TSCA by OPPT and under the Federal Insecticide, Fungicide, and Rodenticide Act
(FIFRA) by EPA's Office of Pesticide Programs (OPP). These modules are shown in dark gray. This
assessment relies on the jointly (OPP/OPPT) completed Environmental Hazard Assessment (U.S. EPA
2024f), the Chemistry, Fate, and Transport Assessment (U.S. EPA 2024b). as well as OPPT's
Environmental Release Assessment (U.S. EPA 2024g) and Environmental Exposure Assessment (U.S.
EPA. 2024g) modules.

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Figure 1-1. Risk Evaluation Document Summary Map

EPA published the Final Scope for the Risk Evaluation for Formaldehyde; CASRN 50-0-0 (U.S. EPA.
2020) in August 2020. Also called the "final scope document," it describes the hazards, exposures,
COUs, and other factors EPA expected to consider in its formaldehyde risk evaluation in accordance
with the requirements of TSCA section 6(b)(4)(D). Following publication of the final scope document,
EPA considered and reviewed reasonably available information2 in a fit-for-purpose approach to
develop this risk evaluation, leveraging existing EPA assessment work, collaborating across offices,
relying on best available science consistent with TSCA section 26(h), and basing the analyses on the
weight of scientific evidence as required by TSCA section 26(i). Reasonably available information was
reviewed, and the quality evaluated, in accordance with EPA's Draft Systematic Review Protocol
Supporting TSCA Risk Evaluations for Chemical Substances, Version 1.0: A Generic TSCA Systematic
Review Protocol with Chemical-Specific Methodologies (also called the "Draft Systematic Review

2 "Reasonably available information" means information that EPA possesses or can reasonably generate, obtain and
synthesize for use in risk evaluations, considering the deadlines specified in TSCA section 6(b)(4)(G) for completing such
evaluation. Information that meets these terms is reasonably available information whether or not the information is
confidential business information (CBI) that is protected from public disclosure under TSCA section 14 (40 CFR 702.33).

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Protocol") (U.S. EPA. 202lb), which underwent review by EPA's Science Advisory Committee on
Chemicals (SACC) in April 2022. A full description of the systematic review protocol for
formaldehyde, including chemical-specific protocols, is available in the Systematic Review
Supplemental File (U.S. EPA. 2024m).

These modules leveraged the data and information sources already identified in the final scope
document (U.S. EPA. 2020). OPPT conducted a comprehensive search for reasonably available
information to identify relevant formaldehyde data for use in the risk evaluation. In some modules,
data were also located in collaboration with other EPA offices.

1.2.1 Life Cycle and Production

The Life Cycle Diagram (LCD)—which depicts the COUs that are within the scope of the risk
evaluation during various life cycle stages, including manufacturing, processing, use (industrial,
commercial, consumer), distribution in commerce, and disposal—is shown below in Figure 1-2. The
LCD has been updated since it was included in the final scope document (U.S. EPA. 2020). Agricultural
use products (non-pesticidal) have been included; it was inadvertently omitted under the industrial,
commercial, and consumer uses lifecycle stage in the diagram in the final scope document.

Based on data collected under the Chemical Data Reporting (CDR) rule in 2019, domestic formaldehyde
production volume is between 453 million and 2.3 billion kg/year. CDR requires U.S. manufacturers
(including importers) to provide EPA with information on the chemicals they manufacture or import into
the United States every 4 years. Data collected for formaldehyde is further detailed in the Use Report for
Formaldehyde (CASRN 50-00-0) (Docket: EPA-HQ-QPPT-2018-0438-0028).

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MFG/IMPORT

PROCESSING

Manufacture
(Including
Import)

(453M-2.27B
kg/yr)

INDUSTRIAL, COMMERCIAL, CONSUMER USES RELEASES and DISPOSAL

J.

Processing as Reactant

Adkesives and sealant chemicals (plastics and resin manufacturing;
wood product manufacturing: all other basic inorganic chemical
manufacturing); Intermediate (pesticide, fertilizer, and other
agricultural chemical manufacturing: petrochemical manufacturing;
soap, cleaning compound, and toilet preparation manufacturing)...

Incorporated into Formulation

Petrochemical manufacturing, petroleum, lubricating oil and grease

manufacturing (fuel and fuel additives, lubricant and lubricant
additives; all other basic organic chemical manufacturing): Asphalt,
paving, roofing, and coating materials manufacturing; Solvents which

become part of a product formulation or mixture (paint and coating
manufacturing); Processing aids, specific to petroleum production (oil
and gas drilling, extraction, and support activities)...

Incorporated into Article

Finishing agents (textiles, apparel, and leather manufacturing); Paint
additives and coating additives not described by other categories
(transportation equipment manufacturing including aerospace)....

Non-incorporative activities1

Furnishings,Cleaning, and
Treatment/Care Products112

Construction, Paint, Electrical,
and Metal Products1,2

Automotive and Fuel
Products12

Agricultural Use Products1-2

Outdoor Use Products1

Packaging, Paper, Plastic,
Hobby Products1'2

Other Use1

See Conceptual Model for
Environmental Releases and
Wastes

Manufacture
(Including Import)

~

~ Processing

J Uses.

1.	Industrial and/or
commercial.

2.	Consumer

Repackaging (Laboratory chemicals)

¦Sl



Recycling







Figure 1-2. Formaldehyde Lifecycle Diagram

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1.2.2 Conditions of Use

As part of the TSCA risk evaluation, OPPT assessed formaldehyde COUs that were included in the
revised COU technical support document (U.S. EPA. 2024c)—including industrial, commercial, and
consumer applications such as textiles, foam bedding/seating, semiconductors, resins, glues, composite
wood products, paints, coatings, plastics, rubber, resins, construction materials (including insulation and
roofing), furniture, toys, and various adhesives and sealants. The COUs were evaluated using the
corresponding environmental exposure scenarios for aquatic and terrestrial organisms. A description of
COUs is available in the Conditions of Use for the Formaldehyde Risk Evaluation (U.S. EPA. 2024c).

1.3 Changes between Draft and the Revised Assessment

Key updates to the Environmental Risk Assessment from the assessment published with the draft risk
evaluation are summarized below:

• EPA has updated the key points summary to be clear that the risk evaluation concludes no
environmental risk from TSCA COUs.

• EPA has added Appendix C to demonstrate consideration of deposition from air to water using
Henry's Law constant and potential ecological hazards.

• EPA has added language to Section 2.1 to clarify what ambient air concentrations of
formaldehyde were used as a reference.

1.4 Chemistry, Fate, and Transport Assessment

EPA considered all reasonably available information identified by the Agency through its systematic
review process under TSCA and submissions under FIFRA to characterize the physical and chemical
properties as well as the environmental fate and transport of formaldehyde. Physical and chemical
properties of formaldehyde, and some known environmental transformation products (methylene glycol,
paraformaldehyde) are provided in Table 1-1. Formaldehyde is expected to be a gas under most
environmental conditions. Due to the reactivity of formaldehyde, it is not expected to persist in most
environmental media but may be abundant due to continual release and formation from secondary
sources like combustion or degradation of other organic chemicals.

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Table 1-1. Physical and Chemical Properties of Formaldehyde and Select Transformation
Products"

Chemical Properties

Formaldehyde

Methylene Glycol

Paraformaldehyde

Molecular formula

CH20

CH2(OH)2

HO(CH20)„H
(n = 8-100)

CASRN for Chemical
Identity

50-00-0

463-57-0

30525-89-4

Molecular weight

30.026 g/mol

48.02 g/mol

(30.03)n g/mol (varies)

Physical form

Colorless gas

Colorless liquid

White crystalline solid

Melting point

-92.0 to-118.3 °C

-43.8 °C

120 to 170 °C

Boiling point

-19.5 °C

131.6 °C

None identified

Density

0.815 g/cm3 at 20 °C

1.20 g/cm3

1.46 g/cm3 at 15 °C

Vapor pressure

3,890 mmHg at 25 °C

3.11 mmHg at 25°C

1.45 mmHg @ 25 °C

Vapor density

1.067 (air = 1)

None identified

1.03 (air = 1)

Water solubility

<55% 400 to 550 g/L

Miscible

Insoluble

Octanol/water partition
coefficient (log Kow)

0.35

-0.79

N/A

Henry's Law constant

3.37E-7 atm/m3mol
at 25 °C

1.65E-7 atm/m3mol
at 25 °C

N/A

11 Physical and chemical properties for formaldehyde, methylene glycol, and paraformaldehyde are considered
best estimates. Because the chemical substance often exists in a mixture at varying concentrations, these
properties can vary based on the equilibration with other chemical substances present. Quality ratings for
formaldehyde and select transformation products can be found in the Chemistry, Fate, and Transport Module
(U.S. EPA. 2024b).

In water, formaldehyde quickly hydrates in seconds to form methylene glycol which can polymerize to
form oligomers of various chain lengths, and paraformaldehyde (U.S. EPA. 2024b I which are all
structurally different compounds when compared to formaldehyde (Figure 1-3). Formaldehyde is not
expected to be found in aquatic systems for this reason (U.S. EPA. 2024e).

0

Ah

! ormaldchyde

H'°"H
wator

HO OH

II H

methylene glycol

>fo}H

1 Jn=2-7

HO

multiple methylene glycols

Hoj^o}*

H

n=8-100
paraformaldehyde

Figure 1-3. Chemical Equilibria for Formaldehyde in Aqueous Solutions

Adapted from (Bover et al.. 2013).

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In soil, formaldehyde is also expected to quickly transform to products that are structurally dissimilar to
the parent formaldehyde; thus, formaldehyde is not expected to be found in soil (U.S. EPA. 2024b). The
transformation products are generally expected to have negligible toxicity; however, not all
transformations can be accounted for due to the highly reactive nature of formaldehyde. Formaldehyde
can be formed in the early stages of plant residue decomposition in soil and is degraded by bacteria in
the soil. Formaldehyde is expected to undergo abiotic (hydration and nucleophilic addition) chemical
reactions in soils to form other compounds.

In air, formaldehyde is susceptible to direct and indirect photolysis; however, it may persist in air
environments with low or no sunlight (e.g., nighttime). As such, the primary exposure route for
formaldehyde is expected to be the air pathway (U.S. EPA. 2024e). More specifically, the half-life of
formaldehyde in air depends on the intensity and duration of sunlight and ambient conditions such as
temperature and humidity. Under direct sunlight, formaldehyde will undergo photolysis with a half-life
up to 4 hours yielding mainly hydroperoxyl radical (HO2), carbon monoxide (CO), and hydrogen (H2).
In the absence of sunlight, formaldehyde can persist with a half-life up to 114 days.

Bioconcentration and/or bioaccumulation is not expected for formaldehyde due to the physical and
chemical properties of the substance (U.S. EPA. 2024b). Furthermore, formaldehyde has a log Kow of
0.35 that similarly confers low potential for bioaccumulation (BAF <1) in both aquatic and terrestrial
organisms (U.S. EPA. 2024b). Given the log Kow and associated low BAF, in conjunction with the
reactivity of formaldehyde, it is not expected to accumulate in the environment. Therefore, no evaluation
of the potential trophic transfer of formaldehyde was conducted.

EPA has high confidence in the overall fate and transport profile of formaldehyde and
paraformaldehyde; however, the Agency is less confident in the overall fate and transport of the
transformation products methylene glycol and poly(oxy)methylene glycol. Key sources of uncertainty
for this assessment are related to formaldehyde equilibrium in various media and subsequent
transformation. In cases where there are little fate and transport data, EPA relied on physical and
chemical properties to describe the expected fate and transport of the respective chemical. As such,
while EPA has some uncertainty in the precision of a specific parameter value, it has confidence in the
overall fate and transport profile of formaldehyde. Additional details can be found in the Chemistry,

Fate, and Transport Assessment for Formaldehyde (U.S. EPA. 2024b).

1.5 Environmental Release Assessment

Formaldehyde is directly released to all three environmental media—air, land, and water—from TSCA
COUs (U.S. EPA. 2024g). It is also released to the environment from other uses (e.g., as a pesticide), as
a transformation product of different parent chemicals, and from combustion sources.

EPA reviewed release data from the Toxics Release Inventory (TRI; data from 2016-2021), Discharge
Monitoring Report (DMR; data from 2016-2021), and the 2017 National Emissions Inventory (NEI) to
identify releases to the environment that are relevant to the formaldehyde COUs. In addition, totals
releases reported to TRI in 2022 and NEI in 2020 have been noted in the Environmental Release
Assessment for Formaldehyde (U.S. EPA. 2024g). From review of these databases, waste streams
containing formaldehyde are being directly discharged to surface water, indirectly discharged to publicly
owned treatment works (POTW)/wastewater treatment (WWT) plants, disposed of via different land
disposal methods (e.g., landfills, underground injection), sent to incineration, and emitted to air via
fugitive and stack releases.

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Based on TRI and DMR reporting from 2016 to 2021, less than 150,000 kg each year of formaldehyde
are directly discharged to surface water for TSCA-related activities based on reporting from 168
facilities. Approximately 2 million kg each year are indirectly discharged to POTWs or other wastewater
WWT plants according to reporting from 168 facilities (U.S. EPA. 2024g). Based on a review of these
databases, waste streams containing formaldehyde are transferred to POTW or WWT plants, biological
wastewater treatment systems have shown a mean removal efficiency of 99.9 percent for formaldehyde
based on literature and 92 percent removal of methylene glycol through biodegredation based on
EPISuite™ estimates (U.S. EPA. 2024b). These disposal routes provide additional time for
formaldehyde and methylene glycol to further transform to chemically dissimilar products in the
presence of water prior to being discharged to surface water.

Based on TRI reporting from 2016 to 2021, most formaldehyde waste is disposed of via land disposal
methods. The most significant method of land disposal of formaldehyde is via underground injection
with 22 sites disposing of more than 5 million kg of formaldehyde annually. The amount of waste
reported to be disposed of in RCRA Subtitle C landfills and other landfills varies across the reporting
years from 200 facilities reporting a total of 423,517 kg per year in 2016 to 127,348 kg per year in 2021.
Other land disposal methods (e.g., surface impoundments, solidification/stabilization) are also reported
at lower levels. Formaldehyde is not expected to persist in water or soils; thus, EPA determined that
additional analyses of releases to water or land were not needed and targeted its review of release
information to fugitive and stack emissions of formaldehyde from TSCA COUs.

EPA identified more than 150,000 point source emission data records (including unit-level estimates) for
formaldehyde across the two EPA databases (TRI data from 2016-2021 and 2017 NEI). To characterize
this amount of data, EPA utilized the self-reported North American Industry Classification System
(NAICS) codes to assign sites into CDR industrial sectors. These industrial sectors can be directly
correlated with the TSCA COUs, as further discussed in the Environmental Release Assessment for
Formaldehyde (U.S. EPA. 2024g). Most TSCA COUs indicate one or more industrial sectors, and in
some cases an industrial sector can appear in more than one TSCA COU. Therefore, an industrial sector
may be associated with multiple formaldehyde TSCA COUs.

For this fit-for-purpose TSCA risk assessment, EPA targeted its review of environmental releases to
point sources, and did not review the road, nonroad, and other automotive exhaust information
identified, as formaldehyde produced from combustion sources is not assessed as an independent COU
subcategory in this risk evaluation. The Agency focused its environmental release assessment on total
facility emissions which can include emission from both uses of formaldehyde and combustion sources
at the same facility or, potentially, only combustion sources from that facility.

EPA categorizes the facilities and corresponding release information by industrial sectors that can be
directly correlated to the TSCA industrial COUs. For commercial COUs, EPA used professional
judgement to assign the industrial sector to commercial COUs, where applicable. For a few COUs
(Commercial use - chemical substances in treatment/care products - laundry and dishwashing products;
Commercial use - chemical substances in treatment products - water treatment products; Commercial
use - chemical substances in outdoor use products - explosive materials; and Commercial use -
chemical substances in products not described by other codes - other: laboratory chemicals), releases
were only qualitatively assessed due to limited use information. For the COU Distribution in commerce,
formaldehyde released accidentally during transit has occurred based on available information, but was
not quantified due to uncertainties in the frequency or volume that may occur in the future. Additional
details are provided in the Environmental Releases for Formaldehyde (U.S. EPA. 2024g).

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In the Environmental Release Assessment for Formaldehyde (U.S. EPA. 2024g). EPA identified
approximately 800 TRI facilities between 2016 and 2021 and approximately 50,000 NEI facilities in
2017 with reported air releases of formaldehyde (U.S. EPA. 2024g). From these facilities, EPA
identified the maximum release reported through TRI was 10,161 kg/year-site (Industry Sector [IS]:
Paper Manufacturing) for a fugitive release reported in 2019 and 158,757 kg/year-site (IS: Wood
Product Manufacturing) for a stack release reported in 2017. The NEI program identified sites reporting
as high as 138,205 kg/year-site (IS: Wholesale and Retail Trade) for fugitive releases and 1,412,023
kg/year-site (IS: Oil and Gas Drilling, Extraction and Support Activities) for stack releases reporting in
2017, in which the higher releases are associated with sectors not required to report to TRI. The high
release sites in NEI were associated with natural gas compressor stations and airport operations, which
EPA expects is from combustion sources. The Agency analyzed the release information by the industrial
sector, providing the minimum, median, 95th percentile, and maximum releases across the entire
distribution of reported releases within each industrial sector, as further discussed in thq Environmental
Release Assessment for Formaldehyde (U.S. EPA. 2024g)

In general, EPA has medium to high confidence in environmental releases for industrial COUs3 and low
to medium confidence in commercial COUs.4 EPA has high data quality ratings for TRI and NEI, which
are supported by numerous facility-reported estimates. Some sites that emit formaldehyde may not be
included in these databases if the release amount does not meet the reporting threshold for the respective
program. EPA used total emissions per site that may combine formaldehyde emissions from multiple
COUs if the site's formaldehyde-generating processes are applicable to more than one COU. For
example, a facility may manufacture formaldehyde as well as process formaldehyde as a reactant. In
some cases, the formaldehyde generating process may also fall outside of scope of the risk evaluation.

1.6 Environmental Exposure Assessment

Although formaldehyde is directly released to water, land, and air, formaldehyde concentrations were
not modeled for the water and land pathways because formaldehyde and the corresponding
environmental transformation products are not expected to persist in soil and water based on physical-
chemical and fate and transport characteristics (see Section 1.4). Formaldehyde air concentrations are
estimated and summarized in Section 2.1.

Available environmental formaldehyde monitoring data (i.e., water and ambient air) were reviewed.
While the surface water monitoring data for formaldehyde are limited and have many uncertainties, the
data are consistent with the conclusion that formaldehyde is not likely to be present in surface water.
Formaldehyde concentrations were usually below detection limits. According to the Water Quality
Portal (WQP), of 866 formaldehyde monitoring sampling events between 1969 and 2022 (U.S. EPA et
al.. 2022). only 11 percent of samples reported formaldehyde concentrations. However, most
formaldehyde concentrations were reported from sampling events before 1975 and the quality of the
data could not be verified (U.S. EPA. 2024e). For sampling after 1975, 11 formaldehyde concentrations
were detected but were also low quality due to percent recoveries in lab results. Approximately 90
percent of samples had no characterization of the sampling media (e.g., surface vs. groundwater,
analytical methodology (e.g., [GC/MS]). Also, for approximately 85 percent of samples, there was no
description of the specific forms of formaldehyde measured (e.g., degradants) in water. In addition,
replicate sampling was conducted for only 21 samples. Despite formaldehyde's rapid transformation in
water, repeat sampling was not conducted over time. The low quality of all detected samples diminished
EPA's confidence that the data reasonably represented formaldehyde concentrations in surface water.

3 COUs that are included under the life cycle stage of manufacturing, processing, and industrial use.

4 COUs that are included under the life cycle stage of commercial uses.

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Agency staff contacted state representatives responsible for those data sets but did not receive a
response. Furthermore, monitoring events could not be connected either temporally or spatially with
known formaldehyde releases to water resulting from TSCA COUs. Considering these lines of evidence,
environmental exposures to formaldehyde are not expected via the water pathway.

Extensive ambient air monitoring data are available for formaldehyde. These data show that
formaldehyde is prevalent in ambient air and confirms that air is a major formaldehyde exposure
pathway. Although these data represent real formaldehyde concentrations in ambient air, the source is
unknown and likely a combination of TSCA and other sources (e.g., biogenic, secondary formation of
formaldehyde in the environment). EPA summarizes available formaldehyde ambient air monitoring
data and modeled ambient air concentrations in Section 2.1 of this assessment. Considering these lines
of evidence, the Agency expects formaldehyde will be present in air and could result in exposures to
terrestrial organisms.

1.7 Transformation Products in Environmental Media

Based on the conclusion of the environmental chemistry, fate, and exposure assessments (U.S. EPA.
2024b. e, g), formaldehyde does not persist in water. It rapidly transforms to methylene glycol and
oligomers of various chain length which are similarly reactive and have limited persistence. Because of
their reactivity, fully characterizing downstream exposure is challenging and highly uncertain.

Therefore, these transformation products were not further assessed for risk to aquatic or terrestrial
organisms. Furthermore, EPA does not consider formaldehyde or these transformation products a
concern in aquatic environments. To further support this conclusion, comparative toxicology data for
formaldehyde and transformation products are provided in the Environmental Hazard Assessment (U.S.
EPA. 2024f) and demonstrate that formaldehyde toxicity is protective of transformation product toxicity
to aquatic organisms.

Rapid transformation of formaldehyde is also expected in soil. Characterizing these transformation
products is highly uncertain as they would be dependent on other chemicals present on the soil particle
surface as well as soil moisture. Because they cannot be characterized with any certainty, EPA does not
consider formaldehyde or these transformation products a concern in soil.

This environmental risk assessment focuses on exposure to formaldehyde (only) in air based on
reasonably available data.

1.8 Problem Formulation for Environmental Pathways

Following publication of the final scope document in 2020, EPA considered and reviewed reasonably
available information in a fit-for-purpose approach to determine which pathways were relevant for
assessments. EPA leveraged existing assessment work, collaborating across offices, and relying on best
available science, and based decisions on the weight of scientific evidence as required by TSCA section
26(i) for these risk assessments.

Based on the Chemistry, Fate, and Transport Assessment for Formaldehyde (U.S. EPA. 2024b).
formaldehyde COUs are not expected to result in formaldehyde exposure to aquatic or soil organisms.
Therefore, EPA did not pursue assessments of these exposure pathways. In contrast, the Chemistry,

Fate, and Transport Assessment, as well as ambient monitoring data, indicate that formaldehyde will be
present in ambient air and may result in exposure to terrestrial organisms (inhalation, ambient air
exposure) based on the continuous release of formaldehyde from various formaldehyde COUs. As such,
EPA focuses on releases from TSCA industry sectors to ambient air and subsequent exposure for plants
and terrestrial organisms. EPA's analysis compares the toxicity of formaldehyde to plants (via air

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exposure) and terrestrial vertebrates (via inhalation) to modeled and measured ambient air
concentrations.

2 RISK ASSESSMENT APPROACH

EPA used information from all reasonably available sources to characterize exposure, hazard, and risk
posed from formaldehyde in air to terrestrial organisms. Modeled or measured environmental
concentrations for ambient air reported in the Environmental Exposure Assessment for Formaldehyde
(U.S. EPA. 2024e) were compared to hazard values for terrestrial organisms reported in the

Environmental Hazard Assessment for Formaldehyde (U.S. EPA. 2024f).

2.1 Ambient Air

The highest measured concentration of formaldehyde in ambient air was 60.1 |jg/m3. The highest
modeled concentration of formaldehyde in ambient air was 662 |jg/m3 (U.S. EPA. 2024e). However, this
concentration is based on a maximum release at 100 m from locations in the Retail and Trade Industry
Sector and most likely represents airports and air force bases. Modeled concentrations of formaldehyde
based on the 95th percentile between 100 and 1,000 m are lower but are more representative of chronic
exposures for terrestrial mammals due to their dwelling traits. The highest modeled concentration with
these assumptions was 5.7 |jg/m3 (U.S. EPA. 2024e). EPA sought to contextualize these data by
modeling all potential sources of formaldehye, including biogenic sources, using AirToxScreen. The
sources of these data are summarized below but are described in full in Ambient Air Exposure
Assessment for Formaldehyde (U.S. EPA. 2024a).

EPA used the Ambient Monitoring Technology Information Center (AMTIC) (U.S. EPA. 2022) to
determine measured concentrations of formaldehyde in ambient air. It encompasses anthropogenic
sources, biogenic sources, secondary formation, mobile sources, combustion sources, and other sources;
however, the dataset does not differentiate among the various sources. Samples are submitted to the
AMTIC database on a state-by-state basis. Data are provided at the discretion of the submitting program
pending approval by AMTIC. Data submitted must be collected and quantified using one of the AMTIC
pre-approved methodologies (U.S. EPA. 2021a). Approved sample collection methods included the
automated Fluxsense system, pressure vessel collection, or silica cartridge collection followed by
quantification by UV absorption, HPLC (high-performance liquid chromatography) photo-diode array,
or FTIR (Fourier-transform infrared spectroscopy). Collection durations for Fluxsense systems were set
at 5 minutes while pressure vessel and silica cartridge collection durations ranged from 3 hours to 24
hours. All sampling methods were composite samples and concentrations were averaged over the sample
collection duration. Monitoring locations and annual summary statistics are provided in the Ambient Air
Exposure Module (U.S. EPA. 2024a).

EPA extracted all monitored ambient air concentrations of formaldehyde from the AMTIC ambient air
monitoring dataset across 6 years of data (2015-2020, n = 233,961 samples, 214 locations). These years
were selected to best inform the assessment according to data extracted from TRI for the release
assessment. From this dataset, the highest measured formaldehyde air concentration was 60.1 [j,g/m3
(U.S. EPA. 2022). These data are shown in Figure 2-1. These monitoring data are based on multiple
monitoring sites (n = 195) from 2015 to 2020. It is worth noting that these data represent different
sampling techniques and durations (ranging from 5 minutes to 24 hours sampling periods), but all values
shown are above the detection limit. Method detection limits were provided with the concentration data
by the submitting agency on a sample-by-sample basis and vary significantly between sampling and
quantification methodologies (lxl0~5 |ig/m3 to 55,900 |ig/m3; median = 4.9 |ig/m3).

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EPA used the peer-reviewed Integrated Indoor-Outdoor Air Calculator (IIOAC) to model formaldehyde
concentrations in ambient air. The highest modeled formaldehyde ambient air concentration was 662
|ig/m ' when estimated at 100 m from the release source as noted in the Ambient Air Exposure
Assessment for Formaldehyde (U.S. EPA. 2022). As mentioned however, this distance may not be
representative based on the dwelling habits of terrestrial mammals. Furthermore, this concentration is
estimated for the Retail and Trade Industry Sector and represents airports and military bases. Modeled
concentrations estimated between 100 and 1,000 m of release facilities may be more representative and
ranged from 1.1 x 10~4 to 5.7 |ig/m3. This range was selected to understand localized impacts from site-
ambiguous releasers since formaldehyde will likely undergo complete degradation via photolysis within
hours. However, continuous release of formaldehyde from industrial sources either via fugitive or stack
emissions mean that these terrestrial organisms could be continuously exposed to the estimated
concentration. These values are illustrated in Figure 2-1.

EPA used AirToxScreen to understand the relative contributions of non-TSCA sources to put risks from
TSCA sources in context. AirToxScreen uses the chemical transport model (CMAQ) and the dispersion
model (AERMOD) to estimate ambient air concentrations across the United States. EPA used data from
the 2019 AirToxScreen to understand the relative relationship of formaldehyde concentrations in
ambient air resulting from various sources. The tool uses data from the NEI, which is a comprehensive
and detailed estimate of air emissions of criteria pollutants, criteria precursors, and hazardous air
pollutants from air emissions sources. These data allow EPA to differentiate among modeled emissions
from various source categories such as point, nonpoint and mobile sources, biogenic emissions, and
fires. In this assessment, EPA used data from AirToxScreen to estimate a 95th percentile concentration
of formaldehyde from all modeled biogenic sources. This estimate captures concentrations that are
reasonably expected to occur without human contributions. The Agency used this estimate for
comparison to concentrations from other formaldehyde sources including those that are expected from
formaldehyde TSCA COUs. Figure 2-1 shows where TSCA COUs fall in the distribution of all sources
of formaldehyde according to AirToxScreen.

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AMTIC (Monitoring)
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Table 2-1. Summary of the Most Sensitive Toxicity Endpoints for Terrestrial Organisms Exposed
to Formaldehyde in Air

Endpoint

Toxicity
(Hg/m3)

Exposure
Pathway

Exposure
Duration

Organism

C itation/MRID

NOAEC

1,230

Inhalation

26 weeks

Terrestrial vertebrate (rat)

MRID 00149755

LOAEC

3,680

Inhalation

26 weeks

Terrestrial vertebrate (rat)

MRID 00149755

NOAEC

438

Air

4 weeks

Terrestrial plant (common
bean)

(Mutters et al.,
1993)

LOAEC = lowest-observed-adverse-effect concentration;
NOAEC = no-observed-adverse-effect concentration
11 High-ranking studies from OPPT and OPP systematic re

VIRID = Master Record Identification number;
views

2.2.1 Terrestrial Vertebrate Toxicity

While inhalation toxicity studies on formaldehyde are extensive, many do not report apical endpoints
which are necessary for ecotoxicity risk evaluation. The most sensitive endpoint that captured effects on
an apical endpoint was a 26-week chamber study on adult rats, hamsters, and monkeys exposed to
formaldehyde for 22 hours per day for 26 weeks. Decreased body weights were statistically significant
in rats at a concentration of 3,680 |j,g/m3 from week two (9% decrease) onward (10-15% decrease);
however, no differences were observed in hamsters or monkeys. Although this study's formaldehyde
exposure duration is longer than the daily concentrations modeled 100 m away from TSCA Industry
Sector Releases, the longer duration exposure toxicity endpoints are expected to be protective of those
shorter duration exposures. Lastly, no short-term effects were observed in a 4-week fumigation study on
the common bean (Phaseolus vulgaris) with maximum exposure concentrations of 356 mg/L (438
Hg/m3) (Mutters et al.. 1993).

2.2.2 Plant Toxicity

Several high-quality studies were identified for evaluating the effects of formaldehyde on terrestrial
plants. No short-term effects were observed in a 4-week fumigation study on the common bean
{Phaseolus vulgaris) with maximum exposure concentrations of 356 |_ig/L (438 ng/m3) NOAEC
(Mutters et al.. 1993). although there was a linear increase in growth of shoots beginning at 65 |jg/L (78
Hg/m3 LOAEC) formaldehyde exposure (Mutters et al.. 1993). Reduced growth of pollen tube lengths of
lily plants (Lilium longiflorum) has also been measured with acute formaldehyde exposure with
inhibition of pollen tube growth at 450 ng/m3 with 5 hours of exposure (72.5% reduction in pollen tube
length) and at 1720 |Jg/m3 with 1 hour of exposure through fumigation (13.5% reduction in pollen tube
length) (Masaru et al.. 1976). In Bromeliaceae plants (epiphytes), 12 hours of exposure to formaldehyde
vapor in chamber experiments at a concentration of 1,000 |jg/m3 reduced chlorophyll content by 17.3
percent (Li et al.. 2014).

2.3 Summary of Environmental Risk Assessment

The Agency did not assess risk to aquatic and soil organisms in this risk assessment because exposure is
not expected; thus, risk is not expected. The highest measured concentration of formaldehyde in ambient
air was 60.1 |jg/m3 and the highest modeled concentration in ambient air from a TSCA COU between
100 and 1,000 m was 5.7 |ig/m3 (U.S. EPA. 2024e). Terrestrial organism hazard values are
approximately an order of magnitude above the highest measured and modeled concentration of
formaldehyde in ambient air (Table 2-2). Thus, no risk to terrestrial organisms is expected relative to the
toxicity endpoints.

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Table 2-2. Comparison of Formaldehyde Air Concentrations and Terrestrial Organism Toxicity

Receptor

Most Sensitive Toxicity Endpoint
(M'g/m3)

Highest Measured Concentration in
Ambient Air
(Hg/m3)

Terrestrial vertebrates
(inhalation)

3,680 LOAEC; 1,230 NOAEC

60.1

Terrestrial plants

438 NOAEC

60.1

LOAEC = lowest-observed-adverse-effect concentration; NOAEC = no-observed-adverse-effect concentration

Hazard data suggest terrestrial plants are the most sensitive terrestrial receptor group to formaldehyde air
exposure using apical endpoints. Toxicity to plants ranged from 438 to 34,188 |ag/m3; thus, the lowest
identified toxicity value is likely protective across taxa. Furthermore, the lowest tested concentration for
mammal inhalation was toxic to rats but not hamsters or monkeys. This finding also suggests the most
sensitive value is more broadly protective across taxa. The highest concentration of formaldehyde in
ambient air (60.1 |ag/m3) is 60 times lower than the concentration that elicited effects on mammal
growth (3,680 |jg/m3). It is also 20 times lower than the concentration that did not yield any toxic effect
(1,230 |jg/m3). Lastly, the highest ambient air concentration is 7 times higher than the lowest
concentration that elicited any effect on plant growth (438 |j,g/m3).

Although terrestrial organisms may be exposed to formaldehyde in air, EPA did not identify risk to any
environmental taxa. The Agency has high confidence in this assessment conclusion.

2.3.1 Terrestrial Vertebrate Risk Assessment

The most sensitive toxicity endpoint for terrestrial vertebrate exposure to formaldehyde via inhalation is
at least an order of magnitude higher than the highest measured ambient air concentrations and TSCA
COU-modeled formaldehyde concentrations in air; thus, risk to terrestrial vertebrates via formaldehyde
inhalation is not expected relative to toxicity endpoints (Table 2-2).

There is uncertainty in potential inhalation exposure durations that are relevant for terrestrial organisms.
Most exposures are anticipated to be short and transient in nature—likely on the order of minutes to
hours. The selected toxicity endpoints are based on exposure durations ranging from 4 to 26 weeks. This
mismatch in exposure duration is not particularly problematic but does represent an uncertainty. An
additional uncertainty is the transient nature of most terrestrial organisms and the absence of specific
activity pattern data of such organisms in or around a particular industrial process that could be
attributed to a TSCA COU. As mentioned, EPA has high confidence in its conclusions but
acknowledges that these discrepancies in the available information.

2.3.2 Plant Risk Assessment

Modeled and measured concentration data are approximately 7 times below concentrations that would
result in adverse effects based on available plant toxicity data. As for terrestrial inhalation exposures,
there is uncertainty in the air exposures for plants. The most sensitive reported endpoint for plant air
exposure was associated with a 4-week study in the common bean. Given the expected intermittent and
short duration exposures expected in the environmental due to TSCA COUs, the study duration is longer
than the expected exposure and is assumed to be protective of shorter-term exposures.

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2,3.3 Overall Confidence and Remaining Uncertainties in Environmental Risk
Assessment

OPPT uses several considerations when weighing the scientific evidence to determine confidence in the
environmental risk assessment. These considerations include the quality of the database, consistency,
strength, and precision, biological gradient/dose response, and relevance. This approach is consistent
with the Draft Systematic Review Protocol (U.S. EPA. 2021b).

The Agency has high confidence in the conclusion that there is no risk to aquatic organisms relative to
toxicity endpoints. Multiple lines of supporting evidence support this conclusion. Environmental fate
and transport data indicate formaldehyde rapidly transforms to other forms (chemically dissimilar to
formaldehyde) in water and is expected to have negligible persistence in water (as either formaldehyde
or its hydrated form methylene glycol). In addition, there are limited releases of formaldehyde directly
to surface water. Furthermore, available monitoring data demonstrate formaldehyde is rarely detected in
water. When detected, there have been quality assurance concerns for those data. In addition,
formaldehyde does not bioaccumulate and aquatic organisms are unlikely to have significant uptake
either by absorption or through their diet. These qualities support a high confidence conclusion.

EPA has high confidence in the conclusion that there is no risk to terrestrial organisms relative to
toxicity endpoints via the land pathway. Multiple lines of evidence support this conclusion.
Environmental fate and transport data indicate formaldehyde does not absorb or bind to soil or sediment
and has negligible persistence on land (due to volatility and reactivity of formaldehyde) (U.S. EPA
2024b). The predominant environmental release of formaldehyde to land is disposal via underground
injection (U.S. EPA 2024g). Furthermore, formaldehyde does not bioaccumulate (U.S. EPA 2024b)
and terrestrial organisms are unlikely to have significant dietary uptake of the chemical. These qualities
support a high confidence conclusion. These qualities support a high confidence conclusion.

EPA also has high confidence in the conclusion that there is no risk to terrestrial organism via the air
pathway as ambient air concentrations are approximately an order of magnitude lower than toxicity
values. Both modeled and measured ambient air concentrations support this conclusion and multiple
taxa had representative hazard values for evaluation. Some uncertainty exists in this conclusion due to
the mismatch in between exposure durations and the selected toxicity endpoints, but this does not lower
the Agency's confidence in its conclusion.

Additional details on overall confidence and remaining uncertainties are described in the following
modules/technical support documents: Chemistry, Fate, and Transport (U.S. EPA 2024b).
Environmental Hazard (U.S. EPA. 2024f). Environmental Exposure (U.S. EPA. 2024e). and
Environmental Release (U.S. EPA. 2024g).

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REFERENCES

Bover. IJ; Heldreth. B; Bergfeld. WF; Belsito. DV; Hill. RA; Klaassen. CD; Liebler. DC; Marks. JG;
Shank. RC; Slaga. TJ; Snyder. PW; Andersen. FA. (2013). Amended safety assessment of
formaldehyde and methylene glycol as used in cosmetics. Int J Toxicol 32: 5S-32S.
http://dx.doi.org/10.1177/1091581813511831
Li. P; Pemberton. R; Zheng. G. (2014). Foliar trichome-aided formaldehyde uptake in the epiphytic
Tillandsia velutina and its response to formaldehyde pollution. Chemosphere 119C: 662-667.
http://dx.doi.Org/10.1016/i.chemosphere.2014.07.079
Masaru. N; Svozo. F; Saburo. K. (1976). Effects of exposure to various injurious gases on germination

of lily pollen. Environ Pollut 11: 181-187. http://dx.doi.org/10.1016/0013-9327(76)90082-3
Mutters. RG; Madore. M; Bytnerowicz. A. (1993). Formaldehyde exposure affects growth and
metabolism of common bean. J Air Waste Manag Assoc 43: 113-116.
http://dx.doi.org/10.108Q/1073161X.1993.10467112
U.S. EPA. (2020). Final scope of the risk evaluation for formaldehyde; CASRN 50-00-0. (EPA 740-R-
20-014). Washington, DC: Office of Chemical Safety and Pollution Prevention.
https://www.epa.gov/sites/default/files/2020-09/documents/casrn 50-00-0-
formaldehyde finalscope cor.pdf
U.S. EPA. (2021a). Best practices for review and validation of ambient air monitoring data. (EPA-
454/B-21-007).

U.S. EPA. (2021b). Draft systematic review protocol supporting TSCA risk evaluations for chemical
substances, Version 1.0: A generic TSCA systematic review protocol with chemical-specific
methodologies. (EPA Document #EPA-D-20-031). Washington, DC: Office of Chemical Safety
and Pollution Prevention, https://www.regulations. gov/document/EPA-HQ-QPPT-2021 -0414-
0005

U.S. EPA. (2022). Ambient Monitoring Technology Information Center (AMTIC) - Ambient
Monitoring Archive for HAPs [Database], Washington, DC. Retrieved from
https://www.epa.gov/amtic/amtic-ambient-monitoring-archive-haps
U.S. EPA. (2023). Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
Quality Evaluation and Data Extraction Information for Environmental Release and
Occupational Exposure. Washington, DC: Office of Pollution Prevention and Toxics, Office of
Chemical Safety and Pollution Prevention.

U.S. EPA. (2024a). Ambient air exposure assessment for formaldehyde. Washington, DC: U.S.
Environmental Protection Agency, Office of Pollution Prevention and Toxics.
https J/www, regulations. gov/document/EP A-HQ-QPPT-2023 -0613-0033
U.S. EPA. (2024b). Chemistry, Fate, and Transport Assessment for Formaldehyde. Washington, DC:

U.S. Environmental Protection Agency, Office of Pollution Prevention and Toxics.

U.S. EPA. (2024c). Conditions of Use for the Formaldehyde Risk Evaluation. Washington, DC: U.S.