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EPA Document #EPA-740-D-24-003
March 2024
Office of Chemical Safety and
Pollution Prevention

SEPA

United States

Environmental Protection Agency

Draft Human Health Risk Assessment for Formaldehyde

CASRN 50-00-0

o

March 2024


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25 TABLE OF CONTENTS

26	ACKNOWLEDGEMENTS	6

27	EXECUTIVE SUMMARY	8

28	1 INTRODUCTION	16

29	1.1 Background	16

30	1.2 Risk Evaluation Scope	16

31	1.2.1 Life Cycle and Production Volume	17

32	1.2,2 Conditions of Use	19

33	1.2,3 Other Sources of Formaldehyde in Air	28

34	1.3 Chemistry, Fate, and Transport Assessment Summary	29

35	1.4 Environmental Release Assessment	32

36	1.5 Human Health Assessment Scope	34

37	1.5.1 Conceptual Exposure Models	34

38	1.5.1.1 Industrial and Commercial Activities and Uses	34

39	1.5.1.2 Consumer Activities and Uses	36

40	1.5.1.3 Indoor Air Exposures	38

41	1.5.1.4 General Population Exposures from Environmental Releases	40

42	1.5.2 Potentially Exposed or Susceptible Subpopulations	42

43	2 HUMAN EXPOSURE ASSESSMENT SUMMARY	44

44	2.1 Occupational Exposure Assessment	44

45	2.1.1 Inhalation Exposure Assessment	45

46	2.1,2 Dermal Exposure Summary	46

47	2.2 Consumer Exposure Assessment	47

48	2.3 Indoor Air Exposure Assessment	51

49	2.3.1 Indoor Air Exposure Monitoring Results	52

50	2.3,2 Indoor Air Exposure Modeling Results	56

51	2.3.2.1 Aggregate Indoor Air Exposure	59

52	2.4 Ambient Air Exposure Assessment	59

53	2.4.1 Monitoring for Ambient Air Concentrations	59

54	2.4,2 Modeling Ambient Air Concentrations	60

55	2.4.2.1 Integrated Indoor/Outdoor Air Calculator Model (IIOAC)	60

56	2.4.2.2 AirToxScreen	63

57	2.4.2.3 Human Exposure Model (HEM)	64

58	2.4.3 Integrating Various Sources of Formaldehyde Data	67

59	2.5 Weight of Scientific Evidence and Overall Confidence in Exposure Assessment	68

60	2.5.1 Overall Confidence in Occupational Exposure Assessment	69

61	2.5.2 Overall Confidence in the Consumer Exposure Assessment	70

62	2.5,3 Overall Confidence in the Indoor Air Exposure Assessment	71

63	2.5.4 Overall Confidence in the Ambient Air Exposure Assessment	71

64	3 HUMAN HEALTH HAZARD SUMMARY	73

65	3.1 Summary of Hazard Values	73

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66	3.2 Weight of Scientific Evidence and Overall Confidence in Hazard Assessment	76

67	3.2.1 Overall Confidence in the Acute Inhalation POD	76

68	3,2,2 Overall Confidence in the Chronic, Non-cancer Inhalation POD	76

69	3.2,3 Overall Confidence in the Chronic IUR	77

70	3,2,4 Overall Confidence in the Dermal POD	77

71	3.2.5 Overall Confidence in the Subchronic and Chronic Oral PODs	77

72	4	HUMAN HEALTH RISK CHARACTERIZATION	79

73	4.1 Risk Characterization Approach	79

74	4,1,1 Estimation of Non-cancer Risks	80

75	4.1.2 Estimation of Cancer Risks	81

76	4.2 Risk Estimates	81

77	4.2.1 Risk Estimates for Workers	81

78	4.2.1.1 Risk Estimates for Inhalation Exposures	81

79	4.2.1.2 Overall Confidence in Worker Inhalation Risks	86

80	4.2.1.3 Risk Estimates for Dermal Exposures	88

81	4.2.1.4 Overall Confidence in Worker Dermal Risks	88

82	4.2,2 Risk Estimates for Consumers	88

83	4.2.2.1 Risk Estimates for Inhalation Exposure to Formaldehyde in Consumer Products	89

84	4.2.2.2 Risk Estimates for Dermal Exposure to Formaldehyde in Consumer Products	93

85	4.2,3 Risk Estimates for Indoor Air	94

86	4.2.3.1 Risk Estimates Based on Indoor Air Monitoring Data	94

87	4.2.3.2 Risk Estimates Based on Indoor Air Modeling for Specific TSCA COUs	95

88	4.2.3.3 Integration of Modeling and Monitoring Information and Consideration of Aggregate

89	Risk	97

90	4,2,4 Risk Estimates for Ambient Air	97

91	4.2.4.1 Risk Estimates Based on Ambient Air Monitoring	98

92	4.2.4.2 Risk Estimates Based on Modeled Concentrations near Releasing Facilities	99

93	4.2.4.3 Integration of Modeling and Monitoring Information	104

94	4.2.4.4 Overall Confidence in Exposures, Risk Estimates, and Risk Characterizations for

95	Ambient Air	105

96	4,2.5 Comparison of Non-cancer Effect Levels and Air Concentrations	106

97	4.2.6 Potentially Exposed or Susceptible Subpopulations	107

98	4.3 Aggregate and Sentinel Exposures	Ill

99	5	NEXT STEPS	113

100	REFERENCES	114

101	APPENDICES	123

102	Appendix A ABBREVIATIONS AND ACRONYMS	123

103	Appendix B LIST OF DOCUMENTS AND SUPPLEMENTAL FILES	125

104	Appendix C DETAILED EVALUATION OF POTENTIALLY EXPOSED AND

105	SUSCEPTIBLE SUBPOPULATIONS	127

106	C,1 PESS Based on Greater Exposure	127

107	C.2 PESS Based on Greater Susceptibility	131

108	Appendix D AMBIENT AIR RISK ESTIMATES - COMMERCIAL USES	140

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Appendix E DRAFT OCCUPATIONAL EXPOSURE VALUE DERIVATION	142

E.l Draft Occupational Exposure Value Calculations	143

E,2 Summary of Air Sampling Analytical Methods Identified	145

Appendix F ACUTE AND CHRONIC (NON-CANCER AND CANCER) OCCUPATIONAL

INHALATION EQUATIONS	147

Appendix G DERMAL EXPOSURE APPROACH	151

LIST OF TABLES

Table 1-1. Categories and Subcategories of Use and Corresponding Exposure Scenario in the Risk

Evaluation for Formaldehyde	20

Table 1-2. Physical and Chemical Properties of Formaldehyde and Select Transformation Products .... 30

Table 2-1. Indoor Air Monitoring Concentrations for Formaldehyde	53

Table 2-2. Formaldehyde Monitored in U.S. Commercial Buildings from 2000 to Present	54

Table 2-3. Representative Residential Indoor Air Exposure Scenarios According to COUs	58

Table 2-4. Overall Monitored Concentrations of Formaldehyde from AMTIC Dataset	60

Table 3-1. Hazard Values Identified for Formaldehyde	74

Table 4-1. Use Scenarios, Populations of Interest, and Toxicological Endpoints Used for Acute and

Chronic Exposures	79

Table 4-2: Population Summary for Cancer Risk Estimates Derived from HEM Modeling of TRI

Releases Formaldehyde to Air	102

Table 4-3. Demographic Details of Population with Estimated Cancer Risk Higher than or Equal to 1 in

1 Million, Compared with National Proportions	103

Table 4-4. Summary of PESS Considerations Incorporated throughout the Analysis and Remaining

Sources of Uncertainty	108

LIST OF FIGURES

Figure 1-1. Risk Evaluation Document Summary Map	17

Figure 1-2. Lifecycle Diagram of Formaldehyde	18

Figure 1-3. Chemical Equilibria for Formaldehyde in Aqueous Solutions	31

Figure 1-4. Conceptual Model for Industrial and Commercial Activities and Uses: Potential Exposure

and Hazards	35

Figure 1-5. Formaldehyde Conceptual Model for Consumer Activities and Uses: Potential Exposures

and Hazards	37

Figure 1-6. Formaldehyde Conceptual Model for Indoor Air: Residential Exposures and Hazards from

Article Off-Gassing	39

Figure 1-7. Formaldehyde Conceptual Model for Environmental Releases and Wastes: General

Population Exposures and Hazards	41

Figure 1-8. Industrial Releases to the Environment and Pathways by Which Exposures to the General

Population May Occur	42

Figure 2-1. Summary of 15-Minute Peak Consumer Inhalation Concentrations (Based on CEM)	49

Figure 2-2. Summary of Average Daily Consumer Inhalation Concentrations, per Year (Based on CEM)

	50

Figure 2-3. Summary of Acute Consumer Dermal Concentrations (Based on Thin Film Model)	51

Figure 2-4. Long-Term Average Daily Concentrations of Formaldehyde According to Air Monitoring

Data Source	55

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Figure 2-5. Modeled Formaldehyde Average Daily Inhalation Concentrations in Indoor Air (According

to CEM)	57

Figure 2-6. Exposure Concentrations by TSCA COU for the 95th Percentile Release Scenario and 95th
Percentile Modeled Concentration between 100 and 1,000 m from Industrial Facilities

Releasing Formaldehyde to the Ambient Air	62

Figure 2-7. Distributions of 2019 AirToxScreen Modeled Data for All Sources, Secondary Production

Sources, Point Sources, and Biogenic Sources for the Contiguous United States	64

Figure 2-8. Map of Contiguous United States with HEM Model Results for TRI Releases Aggregated

and Summarized by Census Block	66

Figure 2-9. Median and Maximum Concentrations (Fugitive, Stack, and Total Emissions) across the 11

Discrete Distance Rings Modeled in HEM	67

Figure 2-10. Distributions of AMTIC Monitoring Data, IIOAC Modeled Data, and AirToxScreen

Modeled Data	68

Figure 4-1. Acute, Non-cancer Occupational Inhalation and Dermal Risk by TSCA COU	83

Figure 4-2. Chronic, Non-cancer Occupational Inhalation Risk by TSCA COU	84

Figure 4-3. Chronic Cancer Occupational Inhalation Risk by TSCA COU	85

Figure 4-4. Peak 15-Minute Inhalation Risk by COUs in Consumer Products	90

Figure 4-5. Chronic Non-cancer Inhalation Risks for Consumer Products by COU	91

Figure 4-6. ADAF-Adjusted Chronic Inhalation Cancer Risk by COUs in Consumer Products	92

Figure 4-7. Acute Dermal Loading Risk by High-End Exposure Scenarios in Consumer Products	93

Figure 4-8. ADAF-Adjusted Lifetime Cancer Inhalation Risk by Indoor Air Monitoring Data Source.. 95
Figure 4-9. Chronic Non-cancer Inhalation Risk Based on Modeled Air Concentrations for Specific

TSCA COUs	96

Figure 4-10. ADAF-Adjusted Cancer Risk for Monitoring and Modeling Ambient Air Data	98

Figure 4-11. Risk Estimates by TSCA COU for the 95th Percentile Release Scenario and 95th Percentile
Modeled Concentration between 100 and 1,000 m from Industrial Facilities Releasing

Formaldehyde to the Ambient Air	100

Figure 4-12. Comparison of Non-cancer Health Effect Levels Reported in People and Indoor and

Outdoor Air Concentrations	106

LIST OF APPENDIX TABLES

Table_Apx C-l. PESS Based on Greater Exposure	128

Table_Apx C-2. Susceptibility Category, factors, and evidence for PESS susceptibility	132

TableApx E-l. Limit of Detection (LOD) and Limit of Quantification (LOQ) Summary for Air

Sampling Analytical Methods Identified	145

Table_Apx F-l. Appendix F Formulae - Symbols, Values, and Units	148

TableApx F-2. Overview of Average Worker Tenure from U.S. Census SIPP (Age Group 50+)	149

Table Apx F-3. Median Years of Tenure with Current Employer by Age Group	150

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ACKNOWLEDGEMENTS

This report was jointly developed by the United States Environmental Protection Agency (U.S. EPA or
the Agency), Office of Chemical Safety and Pollution Prevention (OCSPP), Office of Pollution
Prevention and Toxics (OPPT), and the Office of Pesticide Programs (OPP).

Acknowledgements

The OPPT and OPP Assessment Teams gratefully acknowledge the participation, input, and review
comments from OPPT, OPP, and OCSPP senior managers and science advisors and assistance from
EPA contractor SRC (Contract No. 68HERH19D0022) and ERG (Contract No. 68HERD20A0002).
OPPT and OPP also gratefully acknowledge systematic review work conducted by staff in the Data
Gathering and Analysis Division. Special acknowledgement is given for the contributions of technical
experts from EPA's Office of Research and Development (ORD).

As part of an intra-agency review, the draft formaldehyde risk evaluation was provided to multiple EPA
Program Offices for review. Comments were submitted by ORD, Office of Air and Radiation, and the
Office of Children's Health Protection.

Docket

Supporting information can be found in public docket, Docket ID (EPA.-H.Q-OPPT-2018-043 8).
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.

Authors: Shawn Shifflett (Assessment Lead), Rochelle Bohaty (Management Lead and Branch Chief),
Whitney Hollinshead, Giorvanni Merilis, Kevin Vuilleumier, and Susanna Wegner

Contributors: John Allran, Edwin Arauz, Marcy Card, Bryan Groza, Grant Goedjen, and Myles Hodge

Technical Support: Mark Gibson, Hillary Hollinger.

This draft risk evaluation was reviewed by OPPT, OPP, and OCSPP leadership.

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Formaldehyde - Human Health Risk Characterization - Key Points

Formaldehyde is a highly reactive gas that is ubiquitous in indoor and outdoor environments. It is
widely used in a range of industrial applications, consumer products, and building materials (e.g.,
composite wood products, plastics, rubber, various adhesives and sealants). It also occurs as a product
of combustion, a product of normal metabolism in the human body, and is formed naturally through the
decomposition of organic matter (i.e., biogenic sources).

Health effects of concern for formaldehyde include cancer and respiratory effects such as increased
asthma prevalence, reduced asthma control, and reduced lung function. People may be exposed to
formaldehyde at work, through indoor air, through use of consumer products, and through outdoor air
near sources of formaldehyde. People are often exposed to many sources of formaldehyde
concurrently, some of which are regulated under the Toxic Substances Control Act (TSCA) some of
which are regulated under other laws, and some of which are not regulated at all (for example, the
decomposition of leaves).

This draft human health risk assessment for formaldehyde evaluates the risks of formaldehyde
exposures for workers, consumers, and the general population resulting from TSCA conditions of use
(COUs).

Risk estimates include inherent uncertainties and the overall confidence in specific risk estimates
varies. The analysis provides support for the Agency to make a determination about whether
formaldehyde poses an unreasonable risk to human health and to identify drivers of unreasonable risk
among exposures for people (1) with occupational exposure to formaldehyde, (2) with consumer
exposure to formaldehyde, (3) with exposure to formaldehyde in indoor air, and (4) who live or work
in proximity to locations where formaldehyde is released to air. Concurrent with this draft TSCA Risk
Evaluation, EPA is releasing a preliminary risk determination for formaldehyde.

While EPA is making this risk determination, EPA will consider the standard risk benchmarks
associated with interpreting margins of exposure and cancer risks. However, EPA cannot solely rely on
those risk values. The Agency also will consider naturally occurring sources of formaldehyde (i.e.,
biogenic, combustion, and secondary formation) and associated risk levels therefrom, and consider
contributions from all sources as part of a pragmatic and holistic evaluation of formaldehyde hazard
and exposure in making its unreasonable risk determination. If an estimate of risk for a specific
exposure scenario exceeds the benchmarks, then the decision of whether those risks are formally
unreasonable under TSCA must be both case-by-case and context driven in the case of formaldehyde.
EPA is taking the risk estimates of the human health risk assessment (HHRA), in combination with a
thoughtful consideration of other sources of formaldehyde, to interpret the risk estimates in the context
of making an unreasonable risk determination.

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EXECUTIVE SUMMARY

Sixty-two conditions of use of formaldehyde were determined to be within the scope of TSC A and were
assessed by OPPT. These conditions of use were identified as part of the Final Scope for the Risk
Evaluation for Formaldehyde 50-00-0 (U.S. EPA. 2020c) and recently updated to better reflect the
Agency's understanding of the sources of formaldehyde. Examples of the conditions of use considered
in the TSCA risk evaluation are listed below with a comprehensive list provided in the Draft Conditions
of Use for the Formaldehyde Risk Evaluation (	024c); these include

•	manufacturing of formaldehyde,

•	processing and manufacturing of articles and products,

•	composite wood products,

•	plastics used in toys,

•	rubber materials, and

•	various adhesives and sealants.

Readily available information indicates that formaldhyde is released to air, land, and water from various
TSCA conditions of use. Although the draft formaldehyde risk evaluation considered each of these
pathways of exposure, some of these releases result in negligible exposure based on the chemistry, fate,
and transport properties of formaldehyde. Formaldehyde exposures by those pathways were not assessed
further. These include

•	sediment and water including drinking water, and

•	soils, biosolids, and landfills.

Similarly, some conditions of use were considered for consumer scenarios and result in negligible
exposure based on the chemistry, fate, and transport properties of formaldehyde. Other conditions of use
could not be assessed due to the limitation of available models and data. These conditions of use are

•	water treatment,

•	laundry detergent, and

•	lawn and garden products.

This Draft Human Health Risk Assessment for Formaldehyde focuses on human exposure to
formaldehyde from industrial, occupational, and consumer activities via inhalation of indoor and
outdoor air and dermal (skin) routes. Exposure to workers, consumers and people within the general
population have been assessed under specific conditions of use. Not all conditions of use result in
formaldehyde exposure for all populations. Among the populations assessed are potentially exposed or
susceptible subpopulations (PESS), which are people who have higher exposures or are more susceptible
so may be at greater risk of adverse health effects from formaldehyde. Example populations (including
PESS), routes of exposure, and conditions of use include the following:

•	worker inhalation and dermal exposure during manufacturing, processing, distribution, use and
disposal of formaldehyde;

•	consumer (based on highest expected exposure among all ages) inhalation and dermal exposure
from use of paint, laundry detergents, hand and dishwashing soaps, drain and toilet cleaners,
textile and leather finishing products, varnishes and floor finishes, rubber mats, adhesives, caulks
and sealants, liquid photographic processing solutions, and non-spray lubricants that contain
formaldehyde;

•	general population (all ages) inhalation exposure to indoor air from products used in new
construction of homes and mobile homes (e.g., wood materials, furniture seat covers,); and
automobiles with products that contain formaldehyde; and

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• general population (all ages) inhalation exposure to outdoor air near industrial facilities that
release formaldehyde.

As mentioned, there are many formaldehyde sources. Not all sources are considered in the Draft TSCA
Risk Evaluation, either because they occur naturally or because they are regulated under other statutes.
These include

forest fires;
combustion1;

tail-pipe emissions from cars, trucks, and
other vehicles;

plastic products used for food storage
and distribution;
animal feed;

biogenic sources (like trees and wood
chips);

secondary formation2;

drugs for fisheries and hatcheries;

pesticides and other formaldehyde uses

regulated by the Food and Drug

Administration;

pacifiers and baby bottles; and,

embalming or as a preservative from

funeral homes and taxidermy.

These other sources can produce substantial amounts of formaldehyde resulting in exposures in the
occupational, indoor, and outdoor environments. For example, biogenic concentrations can contribute
upwards of 25 percent of the total formaldehyde concentration and secondary formation can account for
as much as 80 percent in ambient air, depending on the circumstances.

Hazard Values

Human health hazard data for this draft assessment were obtained through many sources including
collaboration with ORD and OPP as well as through the TSCA systematic review process. In addition,
OSCPP is relying on the peer reviews provided by the National Academies of Sciences, Engineering,
and Medicine and the Human Studies Review Board on certain aspects of the human hazard assessment.

OPPT is using the inhalation unit risk for nasopharyngeal cancer as derived in the draft EPA IRIS
Toxicological Review of Formaldehyde - Inhalation (	322b). Although inhaled

formaldehyde has been associated with multiple types of cancer in humans, including nasopharyngeal
and myeloid leukemia, the myeloid leukemia findings are not sufficient to develop quantitative estimates
of cancer risk. While there may be uncertainty on the extent to which other mechanisms contribute to the
carcinogenicity of formaldehyde, the IRIS assessment concluded that a mutagenic action contributes to
risk of nasopharyngeal cancer from inhaled formaldehyde. To account for the potential increased
susceptibility that may be associated with early life exposure to formaldehyde, OPPT modified this
cancer value using age-dependent adjustment factors for exposure scenarios that include early life.

Formaldehyde exposure is also associated with a range of respiratory and non-respiratory health effects
in humans—including reduced pulmonary function, increased asthma prevalence, decreased asthma

1	Formaldehyde can be emitted from many types of combustion, from naturally occurring wildfires and burning candles to
household appliance and industrial combustion turbines. These sources can also include tailpipe emissions (including cars,
trucks, and boats); and emissions from fires (including wildfires, accidental fires, and agricultural burning). Some
combustion activities could be included in the evaluation of other conditions of use under TSCA such as processing or other
similar industrial use. However, given the number of potential sources of formaldehyde production in the home, occupational
settings and in the environment, EPA did not consider formaldehyde from the combustion sources independent of other
TSCA COUs due to their abundant nature.

2	Formaldehyde is also largely found in the environment due to secondary formation of the chemical after degradation of
other compounds, for example when a chemical undergoes chemical reactions in the air and forms formaldehyde. Some
secondary formation may be a result of TSCA conditions of use but these cannot be distinguished from all other secondary
formations because they are so abundant.

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control, allergy-related conditions, sensory irritation, male and female reproductive toxicity, and
developmental effects. OPPT is using a chronic point of departure for pulmonary function in children
derived from the draft EPA IRIS Toxicological Review of Formaldehyde - Inhalation. Sensory irritation
(e.g., eye irritation) observed in adults is the critical effect for non-cancer respiratory effects from
breathing formaldehyde for more than 15 minutes. Skin sensitization observed in adults is the critical
effect for assessing formaldehyde exposure via the dermal routes.

Oral hazard data are also available for formaldehyde but were not used in the risk assessment because
exposure was not expected.

Exposure for Workers and the General Population

Many data sources were used to evaluate exposures to humans (workers; consumers and general
population, both including children) from indoor and outdoor air as well as dermal exposures. These
include measured and model estimated concentrations data. There are many conditions of use and many
different exposure scenarios for each population assessed.

Workers

Worker exposure to formaldehyde via inhalation and dermal are expected to result in the highest
formaldehyde exposures among the assessed populations. Workplace concentrations of formaldehyde
vary based on activities performed (i.e., manufacturing, processing, industrial, and commercial settings).
Individuals in workplaces whose duties are not directly associated with manufacturing, processing, or
use of formaldehyde (i.e., occupational non-users [ONUs] such as supervisors] who may be near or
within the same workspace (i.e., breathing the same air) are also expected to be exposed to
formaldehyde at similar concentrations.

Inhalation exposures were estimated based largely on measured formaldehyde concentrations in
occupational settings. Monitoring data were available for many scenarios. However, monitoring data are
not available for three conditions of use in commercial settings and were thus modeled. These model
estimates generally fell within the range of monitored workplace concentrations. Across all conditions of
use, full work shift (8 to 12 hours) inhalation exposure estimates were between 7.5 to 17,353.3 |ig/m3.
Peak inhalation estimates for workers were between 86 to 237,902 |ig/m3 across all conditions of use.
The highest inhalation exposure was based on modeled estimates for use of formulations containing
formaldehyde in automotive care products. Occupational exposure concentrations, as expected, are
generally higher than modeled and measured outdoor and indoor formaldehyde air concentrations. EPA
has an overall medium confidence in the reported exposure estimates because most of the values are
based on recent (1992 to 2020) real workplace monitoring data from multiple sources and therefore are
expected to be reflective of current industrial practices. The Agency does not have higher overall
confidence in the reported exposure estimates because the sources did not always provide supplemental
information such as worker activities and associated process conditions. Therefore, EPA made
assumptions in integrating monitoring data.

Short-term dermal exposures were estimated based on liquid contact with formulations containing
formaldehyde. Dermal exposure estimates ranged from 0.56 to 3,090 |ig/cm2. The highest dermal
exposure was estimated during spray application of products such as paints and automotive care
products. EPA has medium confidence in the dermal exposure estimates because the estimates were
derived using a standard peer-review model based on measured data on the retention of liquids on the
skin surface. EPA does not have higher confidence in the reported values because the Agency did not
have monitored formaldehyde dermal exposure data to ground truth these exposure estimates.

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General Population - Consumer Exposures in Residential Settings

Frequent users of products containing formaldehyde are anticipated to be the next highest population
effected due to its use in products and articles that are available to most people for purchase. Some
examples of these consumer products that contain formaldehyde include automotive care products;
fabrics, textiles, and leather products; and adhesives or sealants. Exposure estimates for these products
varies due to the different durations (or activity) of use along with formaldehyde amount acquired from
safety data sheets. This assessment considered concentrations of formaldehyde during and following use
of consumer products in residential settings. Specifically, peak (15-minute) and long-term (annual
average) inhalation exposures as well as short-term dermal exposures were estimated. For a subset of
conditions of use, longer-term or lifetime exposure scenarios were assessed based on known consumer
use activities.

Seven conditions of use were evaluated for peak inhalation exposures. Fifteen-minute concentration
estimates ranged from 1.72 to 2,500 |ig/m3. The highest concentrations were for products like floor
covering, foam seating, and bedding. Four conditions of use were evaluated for chronic consumer
inhalation exposure to formaldehyde. These conditions of use were selected because the uses are
expected to be the most substantial contributors to long-term inhalation exposures based on the expected
consumer activity profile and formaldehyde concentrations in the product. Annual estimated
formaldehyde concentrations ranged from 0.04 to 23.83 |ig/m3. The highest concentrations were for arts,
crafts, and hobby materials. EPA has medium confidence in the inhalation exposure estimates based on
the number of monitoring data sources, use of the EPA's Exposure Factors Handbook (U.S. EPA.: )
and survey data on consumer behavior and activities, and chemical amounts report on product-specific
safety data sheets. Monitoring data that can be tied to specific consumer conditions are not available.
Formaldehyde concentrations from consumer products are expected to be represented in the available
indoor air monitoring data as an aggregate concentration with other consumer and indoor air sources.

Dermal short-term exposures for consumers were estimated based on contact with products containing
formaldehyde. Nineteen conditions of use were evaluated with estimated short-term formaldehyde
dermal loading rates ranging from 1.03 to 3,090 |ig/cm2. The highest concentrations were estimated to
be for exterior car waxes and polishes followed by photographic processing solutions. EPA has medium
confidence in these estimates because there are no monitoring data available to ground truth these
concentration estimates.

General Population - Indoor Air Exposures in Residential and Vehicular Settings
There are many sources of formaldehyde within residences (homes and mobile homes) and vehicles. As
mentioned, these include both TSCA sources such as building materials, finishes such as wood flooring
and paint, and foam cushions on furniture, and other sources such as combustion sources like candles,
fireplaces, and stoves. Additionally, consumer products containing formaldehyde may also contribute to
indoor concentrations of formaldehyde.

The highest formaldehyde concentrations from TSCA sources are expected in newly constructed homes
and mobile homes. In these settings, multiple sources of formaldehyde contribute to total indoor air
concentrations especially during the peak product emission period when new formaldehyde containing
articles and products are introduced. These concentrations substantially diminish within the first two
years of the product life based on open literature data. The peak exposure to formaldehyde from these
products is expected to occur within one year of use or manufacture. Indoor air concentrations can also
be high when new materials like hardwood floors or wallpaper are installed in homes. Similarly, fabric
in new furniture may also release formaldehyde in indoor environments after being introduced.
Therefore, formaldehyde concentrations in indoor environments are expected to vary over longer time

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periods (e.g., an individual's lifetime) and are highly dependent on an individual's propensity to move to
new homes as well as their purchasing behaviors.

Four conditions of use in both automobiles and homes were evaluated. The estimated average daily
concentrations of formaldehyde for these conditions of use ranged from 5.19 to 423 |ig/m3. The highest
concentration comes from construction and building materials that cover large surface areas like
hardwood floors. These modeled concentrations represent high-end estimates for each condition of use.
Furthermore, many of the products that fall within this condition of use are subject to the new emission
standards under TSCA Title VI (	2697) which have not been fully implemented.

Monitoring data from the American Healthy Homes Survey II suggests that concentrations of
formaldehyde range from 0.27 to 124.2 |ig/m3 for all homes, with 95 percent of homes having
concentrations below 46 |ig/m3. Thus, indoor exposures to formaldehyde are in general agreement
across available data and sources of formaldehyde; however, monitoring values represent all sources of
formaldehyde in indoor air (including sources that are not subject to TSCA) and cannot be attributed to a
single TSCA condition of use. Similarly, measured concentrations are not expected to reflect full
implementation of the TSCA Title VI (I * I * 1 -.697). which have not been fully implemented as of
the time of publication of this draft risk evaluation. Therefore, it is reasonable to expect that less
formaldehyde will be released from many wood products in the future than occurred in the past.

EPA has medium confidence in the indoor air concentration estimates because the values are based on
product-specific emission rates and product-specific formulations of formaldehyde. However, EPA does
not have high confidence in the indoor air concentration estimates because available monitoring data
could not corroborate the full range of estimates. In addition, the Agency does not have high confidence
because (1) dissipation rates of formaldehyde cannot be determined for indoor air for all types of
furniture, wood, or other products; and (2) the available monitoring data cannot be directly tied to
specific products (e.g., wood and fabric products) and associated conditions of use.

General Population - Outdoor Air Exposures

As mentioned at the beginning of this summary, formaldehyde exposures in outdoor air (ambient air)
come from many sources including biogenic sources, secondary formation, and conditions of use.
Outdoor air exposures are lower than those in any other setting. However, TSCA condition of use
contributions are highly variable across the United States and only exceed other sources in specific
locations. The outdoor air exposure assessment only considered exposures from inhalation for
populations living within a half mile of release facilities. This assessment considered short-term (daily
average) and long-term (annual average) inhalation exposures. After evaluating all durations, only long-
term durations appeared to be substantial and relevant for this Draft TSCA Risk Evaluation. Estimated
annual ambient air concentration ranged from 0.0001 to 5.75 |ig/m3. The highest potential exposures
come from operations with nonmetallic mineral product manufacturing as well as textile, apparel, and
leather manufacturing.

Monitoring data from Ambient Monitoring Technology Information Center, based on data collected
between 2015 to 2020, range from 0 to 60.1 |ig/m3 with a median of 1.6 |ig/m3 across more than
300,000 monitored values from 214 sites. Monitoring data could not be linked to specific conditions of
use.

Since monitored concentrations represent total aggregated concentrations from all contributing sources,
while these values are not directly comparable to IIOAC modeled concentrations alone, by considering
multiple data sources (modeled concentrations, biogenic and secondary sources), EPA found

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considering these three primary contributors together represent a large portion of the total monitored
concentrations and does not result in concentrations outside of or well above any monitored
concentration.

EPA has high confidence in the outdoor air concentration estimates because the values are based on
reported formaldehyde releases from EPA databases, uses standard risk assessment approaches and
utilizes more refined models to better understand population and demographics near releasing facilities.

Risk Characterization

People are regularly exposed to formaldehyde in their workplace, in their vehicles, and in their homes.
People may also be exposed to formaldehyde due to its natural formation in the environment and as a
natural part of human metabolism.

Worker Risk Characterization

Based on available occupational monitoring data and exposure modeling estimates, worker exposure to
formaldehyde is expected to be higher than exposures from naturally occuring sources. This assessment
does not assume personal protective equipment use to account for a range of possible workplaces. Both
high-end and central tendency exposure estimates were used with the available hazard data to calculate
worker risk for acute, chronic non-cancer, and cancer inhalation effects along with the potential to cause
dermal sensitization.

Results indicate that effects to workers are more likely to be for acute and chronic non-cancer inhalation
effects. Workers may experience sensory irritation from short-term exposures and decreased pulmonary
function or other respiratory effects from longer-term exposures. The hazard values are largely based on
studies in children, but adults may also experience adverse effects at similar concentrations. At high-end
exposure scenarios, results indicate workers may also be at increased risk for nasopharyngeal cancer.
Cancer effects are based on human studies in occupational settings.

The risk estimates for occupational exposures reflect use of standard risk assessment approaches
considering an abundance of high-quality workplace monitoring data that clearly exceed concentrations
of formaldehyde from other sources including natural sources and human hazard data. Likewise, risk
estimates are generally consistent across central tendency and high-end exposure scenarios for workers.
While there are some uncertainties in the assessment, these uncertainties are not expected to change risk
estimates enough to shift the overall risk assessment conclusions but may be great enough to change risk
estimates for specific conditions of use.

Results indicate that effects to workers from dermal exposure that could lead to sensitization with
repeated exposure for all conditions of use except one. All exposure estimates were based on standard
modeling approaches including the assumption of the amount of liquid left on the skin after contact
which is not specific to formaldehyde. The hazard data for skin sensitization is based on controlled
human exposures in adult volunteers and is corroborated by animal and in vitro evidence. The dermal
sensitization data are based on controlled human exposures studies in adults.

Consumer Exposure Risk Characterization

Consumer risk estimates were calculated for acute, chronic non-cancer, and cancer inhalation effects, as
well as dermal sensitization.

Consumers may experience acute sensory irritation (eye irritation) when inhaling peak concentrations of
formaldehyde in their residences when using products that contain high amounts of formaldehyde for

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short durations. These acute effects are based on a robust dataset of evidence for sensory irritation in
humans, including several high-quality controlled exposure studies with relevance for acute exposure
scenarios. The risk estimates reflect use of standard risk assessment approaches and best available data.

Consumers inhaling formaldehyde may also experience decreased pulmonary function and other chronic
effects when those products are used frequently. These effects are based on data from humans at
sensitive lifestages, but it is unclear whether exposure scenarios represent how all people use these
products and articles containing formaldehyde. EPA has substantial data on use patterns of these
products based on surveys conducted on consumer activities and behaviors. Similarly, EPA's Exposures
Factors Handbook was used to support consumer exposure analyses. Lastly, safety data sheets were
used to identify concentrations of formaldehyde in consumer products. It is worth noting that
conservative estimates from these data sources may not represent exposures to all consumers using
products and articles containing formaldehyde. The risk estimates reflect use of standard risk assessment
approaches considering best available data for consumers who frequently use products containing
formaldehyde; but understanding the commonness of these practices has some uncertainty because it is
unclear how older data from surveys represents current behaviors and uses.

At high-end exposure scenarios, results indicate consumers may have increased risk for developing
nasopharyngeal cancer, but this is expected to be rare in the general population. The data for cancer
effects are based on human studies that are corroborated in animal studies. EPA believes these risk
estimates are for consumers who frequently use products containing formaldehyde over the course of
many years. However, the Agency does not have information on how common it is that consumers
would use these products for this length of time, and it is unclear how older data from surveys represents
current behaviors and uses.

Consumers using products containing formaldehyde may experience dermal sensitization after acute
exposures to their skin. The hazard data for skin sensitization is based on controlled human exposures in
adult volunteers and is corroborated by animal and in vitro evidence. Risk estimates for these dermal
exposures is based on estimated dermal loading from models. Monitoring data are not available to
determine how common these exposures may be for consumers. Thus, EPA has less certainty in how
common these exposures result in skin sensitization for consumers in the general population.

Indoor Air Exposure Characterization

Indoor air risk estimates were calculated for chronic non-cancer inhalation effects. People who are living
in homes where high concentrations are present may experience decreased pulmonary function and other
chronic effects. These effects are based on data from humans at sensitive lifestages. However, the
exposure scenarios where these effects are seen are mostly limited to homes where high surface area
products like hardwood floors and wallpaper may be introduced. Similarly, these effects may occur in
new homes and mobile homes where all new products may be contributing to high concentrations of
formaldehyde in air. As previously mentioned, the dissipation rate of formaldehyde from these TSCA
conditions of use could not be fully characterized. However, concentrations are anticipated to decrease
with time and ventilation. Generally, new products are expected to have substantially reduced
formaldehyde emissions within 2 years.

In addition to TSCA sources, other sources of formaldehyde may contribute substantially to indoor air
concentrations of formaldehyde. Formaldehyde concentrations from candles, incense, cooking, wood
combustion, and air cleaning devices fall within the range of formaldehyde concentrations from TSCA
conditions of use. Furthermore, the range of concentrations estimated fall within the range of available
monitoring data.

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Many of these other sources of formaldehyde represent temporary emission sources, which may affect
the overall impact on indoor air quality. Further, qualities such as the frequency and duration of use of
these temporary formaldehyde sources (e.g., burning candles or the use of a fireplace), age of the home
and formaldehyde-containing home finishes and furnishings, and ventilation rate will impact the total
concentration of formaldehyde in indoor air and the relative contribution of TSC A and other sources to
the indoor air. Combined, the many factors that may contribute to overall indoor air concentrations and
relative concentrations from TSCA and other uses introduce a significant source of uncertainty in the
indoor air exposure assessment.

EPA has medium confidence in the conclusion of the inhalation risk assessment for indoor air. This is
because the assessment is based on product-specific emission rates, data, and standard methods. While
the monitoring data cannot be tied to individual conditions of use, it is expected to represent aggregate
exposure to formaldehyde resulting from multiple sources. As such, EPA has confidence it is not
underestimating formaldehyde exposure resulting from TSCA conditions of use or across all sources of
formaldehyde.

Ambient Air Risk Characterization

Based on modeling estimates, individuals of the general population living within half mile of a releasing
facility may be exposed to formaldehyde concentrations greater than naturally occuring sources in the
outdoor environment but are generally within the range of concentrations from natural sources like
biogenic sources. Acute, chronic non-cancer, and cancer inhalation risk estimates were calculated. Non-
cancer risk estimates are based on chronic respiratory effects observed in people at sensitive lifestages
and acute sensory irritation observed in controlled human exposures in adults. Cancer risk estimates are
based on effects observed in human studies and corroborated in animal studies.

Results indicate that the general population is not likely to experience sensory irritation from short-term
exposures or decreased pulmonary function or increased asthma prevalence from longer-term exposures
when compared to other formaldehyde exposures; however, in some locations some individuals may be
at increased risk for developing nasopharyngeal and other cancer types. However, this is contingent on
the assumption that an individual lives within a half mile of a releasing facility their entire life. EPA
conducted a higher tier analysis to identify locations where TSCA releases contributed to formaldehyde
concentrations exceeding background concentrations of formaldehyde.

EPA has high confidence in the conclusion of the inhalation risk assessment for the general population.
EPA has this confidence because the assessment is based on a large amount for formaldehyde reported
release data and standard methods. Furthermore, the range of concentrations estimated fall within the
range of available monitoring data. Although the monitoring data cannot be tied to individual conditions
of use, it is expected to represent aggregate exposure to formaldehyde resulting from multiple sources.
As such, EPA has confidence it is not underestimating formaldehyde exposure resulting from TSCA
conditions of use or across all sources of formaldehyde.

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1 INTRODUCTION

1.1	Background

Formaldehyde is a high priority chemical undergoing the Toxic Substances Control Act (TSCA) risk
evaluation process after passage of the Frank R. Lautenberg Chemical Safety for the 21st Century Act in
2016. It is concurrently undergoing a hazard assessment in EPA's Integrated Risk Information System
(IRIS) program and a risk assessment under the Federal Insecticide, Fungicide, and Rodenticide Act
(FIFRA). This Draft Human Health Risk Assessment is a TSCA-specific assessment that will serve to
support risk management needs by the Office of Pollution Prevention and Toxics (OPPT) and is one of
many documents comprising the draft formaldehyde risk evaluation.

In April 2022, EPA's IRIS program released a draft Toxicological Review of Formaldehyde Inhalation
(	I022h) (also called "draft IRIS assessment") for public comment and peer review. OPPT

and OPP have relied upon the hazard conclusions and dose-response analysis presented in the draft IRIS
assessment for inhalation and have coordinated to evaluate additional information on environmental fate
and transport, human health hazard, and environmental hazard consistently across programs.

A list of the regulatory history of formaldehyde can be found in Appendix D of the Final Scope for the
Risk Evaluation for Formaldehyde 50-00-0 (U.S. EPA. 2020c). which includes regulation under the
Clean Air Act, Clean Water Act, Resource Conservation and Recovery Act, and other EPA regulatory
programs and non-EPA programs.

Following publication of the final scope document, EPA considered and reviewed reasonably available
information in a systematic and fit-for-purpose approach to develop this draft formaldehyde risk
evaluation, leverage existing EPA assessment work, collaborate across offices, rely on best available
science, and base it on the weight of the scientific evidence as required by EPA's Risk Evaluation Rule
under TSCA. 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 (U.S. EPA. 2021b). which underwent external peer review by the Science Advisory
Committee on Chemicals (SACC) in July 2021.

1.2	Risk Evaluation Scope

The draft formaldehyde risk evaluation comprises a series of modular assessments. Each module
contains sub-assessments that inform adjacent, "downstream" modules. A basic diagram showing the
layout and relationships of these assessments is provided below in Figure 1-1. In some cases, modular
assessments were completed jointly under TSCA and FIFRA. These modules are shown in dark gray.
This human health risk assessment is shaded blue. High level summaries of each relevant module are
presented in this risk assessment. Detailed information for each module can be found in the
corresponding documents/modules.

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Systematic
Review

Conditions of
Use

Chemistry,
Fate, and
Transport
Assessment

Environmental

Release
Assessment

Environmental

Exposure
Assessment

Environmental

Hazard
Assessment

Environmental
Risk Assessment

Human
Exposure
Assessments

Occupational

Consumer

Indoor Air

AmbientAir

Human Health

Hazard
Assessment

IRIS
Assessment

Human Health
Risk Assessment

Risk
Determination

Legend
^ This Module

| | TSCAAssessment

Q TSCA/FIFRASharedAssessment

I | IRIS Assessment

Group of Assessments

Figure 1-1. Risk Evaluation Document Summary Map

These modules leveraged the data and information sources already identified in the Final Scope of the
Risk Evaluation for Formaldehyde 50-00-0 (U.S. EPA. 2020c). OPPT conducted a comprehensive
search for "reasonably available information" to identify relevant formaldehyde data for use in the risk
evaluation. In some modules, data utilized were also located in collaboration with other EPA offices. As
previously noted, OPPT is relying on the EPA's IRIS draft Toxicological Review of Formaldehyde -
Inhalation (U.S. EPA. 2022b) in the formaldehyde risk evaluation (shaded light gray in Figure 1-1). The
draft IRIS assessment is not part of the TSCA risk evaluation bundle. The approach used to identify
specific relevant risk assessment information was discipline-specific and is detailed in Systematic
Review Protocol for the Draft Formaldehyde Risk Evaluation (U.S. EPA. 2023 a). or as otherwise noted
in the relevant modules.

1.2.1 Life Cycle and Production Volume

The Life Cycle Diagram (LCD)—which 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—is shown below in Figure 1-2. The LCD has been
updated since it was included in the Final Scope of the Risk Evaluation for Formaldehyde CASRN 50-
00-0 (U.S. EPA. 2020c). The commercial and consumer uses for 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 (U.S. EPA. 2020c).

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MFC/IMPORT

PROCESSING

Manufacture
(Including
Import)

(453M-2.27B
kg/yr)

642

643

INDUSTRIAL, COMMERCIAL, CONSUMER USES RELEASES and DISPOSAL

I

Processing as Reactant

Adhesives 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)...See
Table 1-2

Incorporated Into Formulation

Petrochemical manufacturing, petroleum, lubricating oil and grease

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

become part of a product formulation or mixture (paiut and coating
manufacturing); Processing aids, specific to petroleum production (oil
and gas drilling, extraction, and support activities)... See Table 1-2

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).... See
Table 1-2

Repackaging (Laboratory chemicals)

Recycling

Figure 1-2. Lifecycle Diagram of Formaldehyde

Non-incorporative activities1

Furnishings,Cleaning, and
Treatment/Care Products1-2

Construction, Paint, Electrical,
and Metal Products1-2

Automotive and Fuel
Products1-2

Agricultural Use Products1,2

Outdoor Use Products'

Packaging, Paper, Plastic,
Hobby Products1-2

Other I'se1

See Conceptual Model for
Environmental Releases and
Wastes

I I Manufacture
'—' (Including Import)

~ Processing
] Uses.

1.	Industrial and/or
commercial.

2.	Consumer

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644	The current domestic formaldehyde production volume is 453 million to 2.3 billion kg/year. This is

645	based on the Chemical Data Reporting (CDR) Rule under TSCA, which requires U.S. manufacturers

646	(including importers) to provide EPA with information on the chemicals they manufacture or import into

647	the United States every 4 years. For the 2020 CDR cycle, data collected for formaldehyde is further

648	detailed in the Use Report for Formaldehyde (CASRN 50-00-0) (	)

649	1.2,2 Conditions of Use

650	The formaldehyde COUs included in the scope of the draft formaldehyde risk evaluation are reflected in

651	Table 1-1 and the LCD (Figure 1-2) and include industrial, commercial, and consumer applications such

652	as textiles, foam bedding/seating, semiconductors, resins, glues, composite wood products, paints,

653	coatings, plastics, rubber, resins, construction materials (including roofing), furniture, toys, and various

654	adhesives and sealants.

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655 Table 1-1. Categories and Subcategories of Use and Corresponding Exposure Scenario in the Risk Evaluation for Formaldehyde

Conditions of Use

Occupational/Consumer Exposure
Scenario Mapped to COU

Life Cycle
Stage

Category

Subcategories

Manufacturing

Domestic manufacturing

Domestic manufacturing

Manufacturing of formaldehyde

Importing"

Importing

Import and/or repackaging of
formaldehyde

Processing

Reactant

Adhesives and sealant chemicals in: Plastic and resin
manufacturing; Wood product manufacturing; Paint and coating
manufacturing; basic organic chemical manufacturing

Processing as a reactant

Processing

Reactant

Intermediate in: Pesticide, fertilizer, and other agricultural
chemical manufacturing; Petrochemical manufacturing; Soap,
cleaning compound, and toilet preparation manufacturing; All
other basic organic chemical manufacturing; Plastic materials
and resin manufacturing; Adhesive manufacturing; chemical
product and preparation manufacturing; Paper manufacturing;
Paint and coating manufacturing; Plastic products
manufacturing; Synthetic rubber manufacturing; Wood product
manufacturing; Construction; Agriculture, forestry, fishing, and
hunting

Processing

Reactant

Functional fluid in: oil and gas drilling, extraction, and support
activities

Processing

Reactant

Processing aids, specific to petroleum production in all other
basic chemical manufacturing

Processing

Reactant

Bleaching agent in wood product manufacturing

Processing

Reactant

Agricultural chemicals in agriculture, forestry, fishing, and
hunting

Processing

Incorporation into an article

Finishing agents in textiles, apparel, and leather manufacturing

Textile finishing

Leather tanning

Processing

Incorporation into an article

Paint additives and coating additives not described by other
categories in transportation equipment manufacturing (including
aerospace)

Use of coatings, paints, adhesives, or
sealants (non-spray applications)

Use of coatings, paints, adhesives, or
sealants (spray or unknown
applications)

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Conditions of Use

Occupational/Consumer Exposure
Scenario Mapped to COU

Life Cycle
Stage

Category

Subcategories

Processing

Incorporation into an article

Additive in rubber product manufacturing

Rubber product manufacturing

Processing

Incorporation into an article

Adhesives and sealant chemicals in wood product
manufacturing; Plastic material and resin manufacturing
(including structural and fireworthy aerospace interiors);
Construction (including roofing materials); paper manufacturing

Composite wood product
manufacturing

Paper manufacturing

Plastic product manufacturing

Other composite material
manufacturing

Processing

Incorporation into a
formulation, mixture, or
reaction product

Petrochemical manufacturing, petroleum, lubricating oil and
grease manufacturing; Fuel and fuel additives; Lubricant and
lubricant additives; Basic organic chemical manufacturing; All
other petroleum and coal products manufacturing

Processing of formaldehyde into
formulations, mixtures, or reaction
products

Incorporation into a
formulation, mixture, or
reaction product

Asphalt, paving, roofing, and coating materials manufacturing

Incorporation into a
formulation, mixture, or
reaction product

Solvents (which become part of a product formulation or
mixture) in paint and coating manufacturing

Incorporation into a
formulation, mixture, or
reaction product

Processing aids, specific to petroleum production in: oil and gas
drilling, extraction, and support activities; chemical product and
preparation manufacturing; and basic inorganic chemical
manufacturing

Incorporation into a
formulation, mixture, or
reaction product

Paint additives and coating additives not described by other
categories in: paint and coating manufacturing; Plastic material
and resin manufacturing

Incorporation into a
formulation, mixture, or
reaction product

Intermediate in: all other basic chemical manufacturing; all
other chemical product and preparation manufacturing; plastic
material and resin manufacturing; oil and gas drilling,
extraction, and support activities; wholesale and retail trade

Incorporation into a
formulation, mixture, or
reaction product

Solid separation agents in miscellaneous manufacturing

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Conditions of Use

Occupational/Consumer Exposure
Scenario Mapped to COU

Life Cycle
Stage

Category

Subcategories



Incorporation into a
formulation, mixture, or
reaction product

Agricultural chemicals (non-pesticidal) in: agriculture, forestry,
fishing, and hunting; pesticide, fertilizer, and other agricultural
chemical manufacturing





Incorporation into a
formulation, mixture, or
reaction product

Surface active agents in plastic material and resin manufacturing





Incorporation into a
formulation, mixture, or
reaction product

Ion exchange agents in adhesive manufacturing and paint and
coating manufacturing





Incorporation into a
formulation, mixture, or
reaction product

Lubricant and lubricant additive in adhesive manufacturing



Processing

Incorporation into a
formulation, mixture, or
reaction product

Plating agents and surface treating agents in all other chemical
product and preparation manufacturing

Processing of formaldehyde into
formulations, mixtures, or reaction



Incorporation into a
formulation, mixture, or
reaction product

Soap, cleaning compound, and toilet preparation manufacturing

products



Incorporation into a
formulation, mixture, or
reaction product

Laboratory chemicals





Incorporation into a
formulation, mixture, or
reaction product

Adhesive and sealant chemical in adhesive manufacturing





Incorporation into a
formulation, mixture, or
reaction product

Bleaching agents in textile, apparel, and leather manufacturing





Repackaging

Sales to distributors for laboratory chemicals

Import and/or repackaging of
formaldehyde



Recycling

Recycling

Recycling

Distribution

Distribution

Distribution in Commerce

Storage and retail stores

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Conditions of Use

Occupational/Consumer Exposure
Scenario Mapped to COU

Life Cycle
Stage

Category

Subcategories

Industrial Use

Non-incorporative activities

Process aid in: oil and gas drilling, extraction, and support
activities; process aid specific to petroleum production,
hydraulic fracturing

Use of formaldehyde for oilfield well
production

Industrial Use

Non-incorporative activities

Used in: construction

Furniture manufacturing

Industrial Use

Non-incorporative activities

Oxidizing/reducing agent; processing aids, not otherwise listed

Processing aid

Industrial Use

Chemical substances in
industrial products

Paints and coatings; adhesives and sealants; lubricants

Use of coatings, paints, adhesives, or
sealants (non-spray applications)

Use of coatings, paints, adhesives, or
sealants (spray or unknown
applications)

Industrial use of lubricants

Foundries

Commercial
Use

Chemical substances in
furnishing treatment/care
products

Floor coverings; Foam seating and bedding products; Furniture
& furnishings including stone, plaster, cement, glass and
ceramic articles; metal articles; or rubber articles; Cleaning and
furniture care products; Leather conditioner; Leather tanning,
dye, finishing impregnation and care products; Textile (fabric)
dyes; Textile finishing and impregnating/ surface treatment
products.

Installation and demolition of
formaldehyde-based furnishings and
building/construction materials in
residential, public, and commercial
buildings, and other structures

Textile finishing

Leather tanning

Chemical substances in
treatment products

Water treatment products

Use of formulations containing
formaldehyde for water treatment

Chemical substances in
treatment/care products

Laundry and dishwashing products

Use of formulations containing
formaldehyde in laundry and
dishwashing products

Chemical substances in
construction, paint,
electrical, and metal
products

Adhesives and Sealants; Paint and coatings

Use of coatings, paints, adhesives, or
sealants (non-spray applications)

Use of coatings, paints, adhesives, or
sealants (spray or unknown
applications)

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Conditions of Use

Occupational/Consumer Exposure
Scenario Mapped to COU

Life Cycle
Stage

Category

Subcategories

Commercial
Use

Chemical substances in
furnishing treatment/care
products

Construction and building materials covering large surface
areas, including wood articles; Construction and building
materials covering large surface areas, including paper articles;
metal articles; stone, plaster, cement, glass and ceramic articles

Installation and demolition of
formaldehyde-based furnishings and
building/construction materials in
residential, public and commercial
buildings, and other structures

Chemical substances in
electrical products

Machinery, mechanical appliances, electrical/electronic articles;
Other machinery, mechanical appliances, electronic/electronic
articles

Use of electronic and metal products

Chemical substances in
metal products

Construction and building materials covering large surface
areas, including metal articles

Chemical substances in
automotive and fuel
products

Automotive care products; Lubricants and greases; Fuels and
related products

Use of formulations containing
formaldehyde in automotive care
products

Use of automotive lubricants

Use of formulations containing
formaldehyde in fuels

Chemical substances in
agriculture use products

Lawn and garden products

Use of fertilizer containing
formaldehyde in outdoors including
lawns

Chemical substances in
outdoor use products

Explosive materials

Use of explosive materials

Chemical substances in
packaging, paper, plastic,
hobby products

Paper products; Plastic and rubber products; Toys, playground,
and sporting equipment

Use of paper, plastic, and hobby
products

Chemical substances in
packaging, paper, plastic,
hobby products

Arts, crafts, and hobby materials

Use of craft materials

Chemical substances in
packaging, paper, plastic,
hobby products

Ink, toner, and colorant products; Photographic supplies

Use of printing ink, toner and colorant
products containing formaldehyde

Photo processing using formulations
containing formaldehyde

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Conditions of Use

Occupational/Consumer Exposure
Scenario Mapped to COU

Life Cycle
Stage

Category

Subcategories



Chemical substances in
products not described by
other codes

Laboratory chemicals

General laboratory use

Consumer Uses

Chemical substances in
furnishing treatment/care
products

Floor coverings; Foam seating and bedding products; Cleaning
and furniture care products; Furniture & furnishings including
stone, plaster, cement, glass and ceramic articles; metal articles;
or rubber articles

Varnishes and floor finishes

Plastic articles: foam insulation (living
room)

Plastic articles: foam insulation
(automobile)

Drain and toilet cleaners

Textile and leather finishing products

Furniture & furnishings - wood
articles: furniture

Consumer Uses

Chemical substances in
furnishing treatment/care
products

Fabric, textile, and leather products not covered elsewhere
(clothing)

Fabrics: furniture covers, car seat
covers, tablecloth (automobiles)

Fabrics: furniture covers, car seat
covers, tablecloth (living room)

Fabrics: clothing

Consumer Uses

Chemical substances in
treatment products

Water treatment products

Drinking water treatment

Consumer Uses

Chemical substances in
treatment/care products

Laundry and dishwashing products

Laundry detergent (liquid)

Hand Dishwashing Soap/ Liquid
detergent

Consumer Uses

Chemical substances in
construction, paint,
electrical, and metal
products

Adhesives and Sealants; Paint and coatings

Water-based wall paint
Solvent-based wall paint
Glues and adhesives, small scale
Caulk (Sealants)

Consumer Uses

Chemical substances in
construction, paint,

Construction and building materials covering large surface
areas, including wood articles; Construction and building

Building/construction materials - wood
articles: hardwood floors

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Conditions of Use

Occupational/Consumer Exposure
Scenario Mapped to COU

Life Cycle
Stage

Category

Subcategories



electrical, and metal
products

materials covering large surface areas, including paper articles;
metal articles; stone, plaster, cement, glass and ceramic articles

Liquid concrete

Consumer Uses

Chemical substances in
electrical products

Machinery, mechanical appliances, electrical/electronic articles;
Other machinery, mechanical appliances, electronic/electronic
articles

Electronic appliances

Consumer Uses

Chemical substances in
automotive and fuel
products

Automotive care products; Lubricants and greases; Fuels and
related products

Exterior car wax and polish

Lubricants (Non-spray)

Liquid fuels/motor oil

Consumer Uses

Chemical substances in
agriculture use products

Lawn and garden products

Fertilizers (garage/outside)

Consumer Uses

Chemical substances in
packaging, paper, plastic,
hobby products

Paper products; Plastic and rubber products; Toys, playground,
and sporting equipment

Paper articles: with potential for routine
contact (diapers, wipes, newspaper,
magazine, paper towels)

Rubber articles: flooring, rubber mats

Rubber articles: with potential for
routine contact

Plastic articles: other objects with
potential for routine contact

Consumer Uses

Chemical substances in
hobby products

Arts, crafts, and hobby materials

Craft paint - generic

Consumer Uses

Chemical substances in
packaging, paper, and
plastic

Ink, toner, and colorant products; Photographic supplies

Inks applied to skin

Liquid photographic processing
solutions

Disposal6

Disposal

Disposal

Worker handling of wastes

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Conditions of Use

Occupational/Consumer Exposure
Scenario Mapped to COU

Life Cycle
Stage

Category

Subcategories

a The repackaging scenario covers only those sites that purchase formaldehyde or formaldehyde containing products from domestic and/or foreign suppliers
and repackage the formaldehyde from bulk containers into smaller containers for resale. Sites that import and directly process/use formaldehyde are assessed in
the relevant occupational exposure scenario (OES). Sites that that import and either directly ship to a customer site for processing or use or warehouse the
imported formaldehyde and then ship to customers without repackaging are assumed to have no exposures or releases and only the processing/use of
formaldehyde at the customer sites are assessed in the relevant OES.

h Each of the TSCA COU of formaldehyde may generate waste streams of the chemical that are collected and transported to third-party sites for disposal,
treatment, or recycling. Industrial sites that treat, dispose, or directly discharge onsite wastes that they themselves generate are assessed in each COU
assessment. This section only assesses wastes of formaldehyde that are generated during a COU and sent to a third-party site for treatment, disposal, or
recycling.

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1,2,3 Other Sources of Formaldehyde in Air

Formaldehyde is ubiquitous in both indoor and outdoor (ambient) air because it is formed naturally in
the environment and from numerous anthropogenic sources, which include both TSCA (Section 1.2.2)
and other activities. As a result, people are routinely exposed to formaldehyde in indoor and outdoor air,
with indoor air generally having higher concentrations than outdoor air. Robust monitoring data are
available to estimate the concentrations of formaldehyde across common outdoor and indoor
environments. However, attributing measured concentrations to TSCA versus other sources is complex.
This section will provide an overview of these data sources and seeks to differentiate between sources
when possible. This section is not intended to be a comprehensive review of the scientific literature on
this topic but instead provides context for understanding and interpreting the exposures of formaldehyde
from a variety of sources as part of risk characterization and risk determination of COUs under TSCA.

Formaldehyde has been measured in outdoor air across the country. EPA's Ambient Monitoring
Technology Information Center (AMTIC) maintains a database of spatially and temporally diverse air
quality monitoring data that meet specified collection and quality assurance criteria. The Agency used
monitoring data extracted from EPA's AMTIC (U.S. EPA. 2022a) from 2015 through 2021 to
contextualize modeled values as well as characterize total aggregate exposures to formaldehyde from all
possible contributing sources—including sources associated with TSCA COUs and other sources out of
scope for this assessment and not associated with TSCA COUs (e.g., biogenic sources (decay of organic
matter), secondary formation, combustion byproduct formation, other byproduct formation, mobile
sources, and others).These data are described in detail in Sections 2.4.1 and 3.3.2 of the Draft Ambient
Air Exposure Assessment for Formaldehyde (	24a). In addition, satellite data have measured

formaldehyde concentrations across the United States, providing insights on temporal and geographic
trends that help to characterize ambient formaldehyde concentrations (Wane et at.. 2022; Harkev et at..
2021: Zhuet at.. 2017).

Comprehensive modeling efforts have been undertaken to characterize formaldehyde concentrations that
vary across the county. EPA's AirToxScreen is one example that uses release data with chemical
transport and dispersion models to estimate average annual outdoor ambient air concentrations of air
toxics across the U.S. and is validated against available monitoring data. For formaldehyde, this model
estimates concentrations from different sources contributing to ambient air concentrations including
biogenic sources, secondary formation, and point sources. Other sources of formaldehyde are included
but may not be relevant to the scope of this draft risk evaluation for formaldehyde. Accordingly, the
2019 AirToxScreen estimates that secondary formation of formaldehyde accounts for 80 percent of
formaldehyde in ambient air and direct biogenic sources contribute 15 percent. Based on the 2019
AirToxScreen estimates, the calculated ninety-fifth percentile biogenic concentration of formaldehyde in
ambient air was 0.28 |ig/m3 (e.g., Ninety-five percent of estimated concentrations of formaldehyde in
ambient air attributable to biogenic sources based on the 2019 AirToxScreen data all biogenic sources of
formaldehyde are below 0.28 |ig/m3.).

Much like outdoor air, many efforts have been made to characterize formaldehyde in the indoor
environment. Draft data from a recent national survey provides a representative sample of formaldehyde
concentrations in indoor air, showing average residential levels an order of magnitude higher than
outdoor concentrations. The American Healthy Homes Survey II (AHHS II) survey, sponsored by the
U.S. Department of Housing and Urban Development (HUD) along with EPA, was conducted from
March 2018 through June 2019 and measured indoor air concentrations of formaldehyde in U.S. homes
of various ages, types, conditions, and climates (OuanTech. 2021). Across all housing, the weighted-
mean concentration is 23.2 |ig/m3 (95% confidence interval 21.6-25.2 |ig/m3) with 10 percent of homes

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higher than 41.8 |ig/m3. Formaldehyde is introduced into residential indoor air from numerous TSCA
sources (e.g., building materials, finishes such as flooring and paint, and furniture) and other sources
(e.g., fireplaces, gas stoves, candles, photocatalytic air purifiers, and tobacco use). The TSCA sources
are expected to consistently release formaldehyde over long periods of time, with release rates
decreasing over time as the materials age. In contrast, many of the other sources are temporary emission
sources and contribute formaldehyde to the indoor air intermittently. Overall, due to differences in the
ages of building materials, home finishes, and furnishings and differences in presence and use patterns
of other formaldehyde sources in the residence, the relative contributions of formaldehyde from TSCA
and other sources to residential indoor air varies both among homes and over time within a single home.
Thus, despite the availability of quality monitoring data, it remains difficult to discern source
apportionment for the residential environment and there are uncertainties related to assessing exposures
tied to specific TSCA COUs based on this monitoring data. OPPT will solicit comment from the SACC
and the public on additional sources of information that could inform the attribution of other sources of
formaldehyde to support risk characterization.

1.3 Chemistry, Fate, and Transport Assessment Summary

EPA considered 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. This was done as a joint
effort with the OPP. Physical and chemical properties of formaldehyde, as well as some known
environmental transformation products (methylene glycol, paraformaldehyde), are provided in Table
1-2. Formaldehyde is expected to be a gas under most environmental conditions. Due to the reactivity of
formaldehyde, it is not expected to be present in most environmental media but may be abundant in air
due to continual release from multiple sources including from TSCA releases, biogenic sources, and
formation from secondary sources.

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730	Table 1-2. Physical and Chemical Properties of Formaldehyde and Select Transformation

731	Productsa

Chemical Properties

Formaldehyde

Methylene Glycol

Paraformaldehyde

Molecular formula

CH20

CH2(OH)2

HO(CH20)„H
(n = 8-100)

CASRN

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-07 atm/m3mol at
25 °C

1.65E-07

atm/m3mol at 25 °C

N/A

a 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.

732

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

N"

O	n	HO OH	Urt.

hXh . H' -H — „X	' '«=2-7

ormaldehyde W!ito'	methylene glycol	mulliPle

I

ho'Ko}1"1

1 Jn=8-100
paraformaldehyde

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

Adapted from (Bover et al.. 2013).

In soil, formaldehyde is also expected to quickly transform to products that are structurally dissimilar to
parent formaldehyde; thus, formaldehyde is not expected to be found in soil (U.S. EPA. 2024b).
Formaldehyde can be formed in the early stages of plant residue decomposition in soil and is reportedly
degraded by bacteria in the soil (U.S. EPA. 2024b). 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 be present in air
environments with low or no sunlight (e.g., nighttime, indoor). As such, the primary exposure route for
formaldehyde is expected to be the air pathway (U.S. EPA. 2024e). More specifically, the half4ife 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 half4ife
up to 4 hours yielding mainly hydroperoxyl radical (HO2), carbon monoxide (CO), and hydrogen (Fh).
In the absence of sunlight, formaldehyde can persist with a half4ife up to 114 days.

Due to the physical and chemical properties of formaldehyde including a log Kow (0.35), which is
associated with low bioconcentration and bioaccumulation are not expected (U.S. EPA. 2024b).
Therefore, human exposure to formaldehyde via consumption of fish was not expected and therefore not
assessed.

EPA has high confidence in the overall fate and transport profile of formaldehyde and
paraformaldehyde; however, EPA 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, although EPA has some
uncertainty in the precision of a specific parameter value, it has confidence in the overall fate and

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transport profile of formaldehyde. Additional details can be found in the Chemistry, Fate, and Transport
Assessment for Formaldehyde (\ c< « ^ \ ,\)24b).

1.4 Environmental Release Assessment

Formaldehyde is directly released to all three environmental media (air, land, and water) from TSCA
COUs (	!024e). It is also released to the environment during regulated other uses (e.g., use as

a pesticide and U.S. Food and Drug Administration uses), as a transformation product of different parent
chemicals, and from combustion sources.

EPA reviewed release data from the Toxics Release Inventory or TRI (data from 2016 to 2021),
Discharge Monitoring Report (DMR; data from 2016 to 2021), and the 2017 National Emissions
Inventory (NEI) to identify releases to the environment that are relevant to the formaldehyde TSCA
COUs, as stated in Table 1-1. Based on a review of these databases, waste streams containing
formaldehyde are directly discharged to surface water, indirectly discharged to publicly owned treatment
works (POTW) or other wastewater treatment (WWT) plants, disposed of via different land disposal
methods (e.g., landfills, underground injection), sent to incineration, and emitted via fugitive and stack
releases.

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 transferred to POTW/WWT plants for treatment
based on reporting from 168 facilities (	)24e). For these wastewater streams 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 (	24b). These disposal methods

provide additional time for formaldehyde and methylene glycol to further transform to chemically
dissimilar products in the presence of water and chemical, biological, and physical treatment processes
prior to being discharged to surface water.

Based on TRI reporting from 2016 to 2021, most waste of formaldehyde 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/year in 2016 to the most recent year (RY2021)
of 127,348 kg/year. 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 (includes unit-level estimates) for
formaldehyde across the two EPA databases (TRI data from 2016 to 202land 2017 NEI). To
characterize this amount of data, EPA utilized the self-reported NAICS codes to assign sites into CDR
industrial sectors (IS). These industrial sectors can be directly correlated with the TSCA COUs, as
further discussed in the Draft Environmental Release Assessment for Formaldehyde (	24g).

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.

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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 draft risk evaluation. EPA 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 TSCA COUs, EPA used professional
judgement to assign the industrial sector to commercial TSCA COUs, where applicable. For a few
TSCA 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. Additional details
are provided in the Draft Environmental Release Assessment for Formaldehyde (	).

In the Draft Environmental Release Assessment for Formaldehyde (	)24g), EPA identified

approximately 800 TRI facilities between 2016 and 2021 and approximately 50,000 NEI facilities in
2017 with reported air releases of formaldehyde (	|24g). From these facilities, EPA

identified the maximum release reported through TRI was 10,161 kg/year-site (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 program were associated with natural gas compressor stations and airport operations, which EPA
expects is due to formaldehyde produced from combustion sources. EPA 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 the Draft Environmental Release Assessment for Formaldehyde (	24 e)

In general, EPA has medium to high confidence in environmental releases for industrial TSCA COUs3
and low to medium confidence in commercial TSCA 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 does not meet the reporting criteria
for the respective program. EPA used total emissions per site, which may combine formaldehyde
emissions from multiple TSCA COUs if the site's formaldehyde-generating processes are applicable to
more than one TSCA 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 draft risk evaluation.

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;

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

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

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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 distribution in commerce,
formaldehyde released accidently during transit has occurred based on available information, but it was
not quantified due to uncertainties in the frequency or volume that may occur in the future. Additional
details are provided in the Draft Environmental Release Assessment for Formaldehyde (

2024g).

1.5 Human Health Assessment Scope

Generally, EPA expects inhalation to be a major route of exposure for occupational, consumer, indoor
air, and ambient air based on the volatility and presence of formaldehyde in air. Dermal sensitization
from formaldehyde exposure is a rapid effect. Thus, for occupational and consumer COUs where
dermal contact to formaldehyde may occur, EPA expects the dermal route to be another significant
route of exposure to formaldehyde.

A quantitative assessment of the water pathway was not conducted in this risk assessment given the
relatively limited release of formaldehyde directly to surface water, and due to the rapid transformation
of formaldehyde in water based on the physical and chemical properties governing the environmental
fate of formaldehyde in water. Water monitoring data, while limited, demonstrate formaldehyde is not
detected in water as described in more detail in the environmental exposure assessment (U.S. EPA.
2024e). Based on these lines of evidence, EPA does not expect human exposure to formaldehyde will
occur via surface water. In addition, formaldehyde is not expected to persist in land or leach to
groundwater that may be sourced for drinking water based on the physical and chemical properties
governing the environmental fate of formaldehyde in land. Therefore, EPA does not expect human
exposure to formaldehyde will occur via soil, land, or groundwater.

1.5.1 Conceptual Exposure Models

1.5.1.1 Industrial and Commercial Activities and Uses

The conceptual model in Figure 1-4 presents the exposure pathways, exposure routes and hazards to
people from industrial and commercial activities and uses of formaldehyde. EPA evaluated exposures to
workers and occupational non-users (ONU) via inhalation routes and exposures to workers via dermal
routes, as shown in Figure 1-4. Oral exposure may occur through wood or textile dust that deposit in the
upper respiratory tract that is then ingested; however, formaldehyde will continue to evaporate and there
is uncertainty on the amount inhaled that is ingested. For this draft risk evaluation, these exposures were
evaluated as an inhalation exposure.

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INDUSTRIAL AND COMMERCIAL
ACTIVITIES ¦'USES

EXPOSURE PATHWAY

EXPOSURE ROUTE

RECEPTORS

HAZARDS

Manufacturing

Processing

As a reactant/iatennediate
-Incorporation Into an article
-Incorporation into formulation, mixture, or reaction
product

Non-Incorporative Activities

Adhesive! and Sealants

Arts, Craft and Hobby
Materials

Automotive Care

Products

Building Construction

Materials- wood and
engine tied wood
products and other
	products	

Furniture aad
Furnishings not covered
elsewhere

Ink, toner, and colorant
products

Laboratory Chemicals

Launcfry and
dtshwa'hing products

Lawn Products

Cleaning and Furniture
Care Products

Electrical Products

Lubricants and greases
Metal Product?

Packaging

Explosive Products

Fabric, Textile, and
leather products not
elsewhere

P Paints and Coating? [

Floor Covering;

Foam Setting anil
Bedding Products

Paper Products

Personal Care Products

Photographic Supples

Fuel and related
prodacts

Toys, playground and
sporting equipment

W ater Treatment
Products

Recycling

~Q

Liquid Contact



r

f—" 		——

Yapor/Mfet/Ehjst

i.

i

Ik

potentially
I with acute
and/or chronic

exposures

Waste Handling. Treatment, and

Disposal

Fugtthe
Emissions

Wastewater, Liquid wastes,. and Solid Wasters
-!~ (See Mmirmmetttal Release Conceptual Model)

Figure 1-4. Conceptual Model for Industrial and Commercial Activities and Uses: Potential Exposure and Hazards

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Note that fugitive air emissions, as described in Figure 1-4, are those that are not stack emissions and
include fugitive equipment leaks from valves, pump seals, flanges, compressors, sampling connections
and open-ended lines; evaporative losses from surface impoundment and spills; and releases from
building ventilation systems.

1.5.1.2 Consumer Activities and Uses

Formaldehyde is found in consumer products and articles that are readily available for public purchase
at common retailers and through online shopping venues. Formaldehyde may be either a chemical
ingredient in a consumer product or a component in material(s) utilized in the manufacturing of
consumer products or articles (adhesives, resins, glues, etc.) or both. Use of such product is expected to
result in exposures to both consumers who use a product (consumer user) and bystanders (individuals
who are not directly using a product but are exposed while the product is being used by someone else).

Figure 1-5 presents the conceptual model for consumer activities and uses that are in scope for the
TSCA formaldehyde risk evaluation. Formaldehyde-containing consumer products include textiles,
foam bedding/seating, semiconductors, resins, glues, composite wood products, paints, coatings,
plastics, rubber, resins, construction materials (including roofing), furniture, toys, and various adhesives
and sealants. EPA identified these formaldehyde COUs from information reported to EPA through CDR
and TRI reporting, published literature, and consultation with stakeholders for products currently in
production or not discontinued.

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CONSUMER ACTIVITIES &
USES

EXPOSURE
PATHWAY

EXPOSURE
ROUTE

EXPOSED
GROUP

HAZARDS

Arts, crafts, and hobby
materials

Moor coverings; Foam
seating and bedding
products; Furniture &
furnishings; Cleaning
and furniture care
products; Textile
finishing, etc.

Construction and
building materials
covering large surface
areas, including wood,
metal, paper articles,
etc.

Laundry and
dishwashing products

Lawn and garden
products

Machinery, mechanical
appliances, electrical '
electronic articles, etc.

Ink, toner, and colorant
products; Photographic
supplies

Automotive care
products; Lubricants and
greases; Fuels and
related products

Fabric, textile, and
leather products not
co\eied elsewhere
(clothing)

Adhesives and Sealants;
Paint and coatings

Paper products; Plastic
and rubber products;
Toys, and pla> ground
equipment

Water treatment
products

li

Consumer Handling of
Disposal and Waste

'is^osat i

TicpidTMist |	~ Dermal }

c

Consumers

Vapor, Mist

-~I Inhalation

<

Consumers
Bystanders

Hazards Potentially
Associated with Acute
and/or Chronic
Exposures

Wastewater, Liquid Wastes and
Solid Wastes (See Environmental
Releases Conceptual Models)

918

919	Figure 1-5. Formaldehyde Conceptual Model for Consumer Activities and Uses: Potential Exposures and Hazards

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Some consumer products assessed may also have commercial applications. See Table 1-1 for categories
and subcategories of COUs. Inhalation is the primary expected route of exposure for formaldehyde
resulting from consumer activities, however, dermal exposures are also expected. EPA considered
potential oral exposure pathways associated with TSCA COUs, including lawn and garden products and
oral mouthing behaviors in infants and young children. However, because EPA lacks sufficient data to
quantify exposures and risks for any of these pathways, oral exposures were qualitatively assessed for
relevant COUs (e.g., lawn and garden products). Section 2.2 for the Consumer Exposure Module (U.S.

Md) provides more detail about the COUs within the scope of this draft risk evaluation.

1.5.1.3 Indoor Air Exposures

EPA expects formaldehyde exposure to occur in the indoor air environments from several sources via air
including from off-gassing of formaldehyde from various consumer articles. The separation of the
consumer exposure assessment and the indoor air exposure assessment is intentional; each assessment
represents a different context of exposures. The conceptual model in Figure 1-6 presents the exposure
pathways, exposure routes and hazards to people from emitters of formaldehyde in indoor air. For
example, a passenger may be exposed to formaldehyde through inhalation for the duration of a taxi ride
due to formaldehyde off-gassing to air from seat covers within the vehicle.

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936

CONSUMER ACTIVITIES &
USES

EXPOSURE
PATHWAY

EXPOSURE
ROUTE

EXPOSED
GROUP

NA/.A R I)S

Floor coverings: Foam seating
and bedding products: Furniture

& furnishings: Cleaning and
furniture care products: Textile
finishing, etc.

Fabric, textile, and leather products
not covered elsewhere (clothing)

Construction and building

materials covering large surface
areas, including wood, metal,
paper articles, etc.

Paper products; Plastic and
rubber products; Toys, and
playground equipment

Consumer Handling of
Disposal and Waste

Indoor Air/Vapor

Inhal ation

Residents, Drivers,
and Passengei

ivers, \
»ers J

I lazards Potentially
Associated with Acute
and 'or Chronic

Exposures

Solid Wastes I See
Em iionmeutal Releases
Conceptual Models)

937

938	Figure 1-6. Formaldehyde Conceptual Model for Indoor Air: Residential Exposures and Hazards from Article Off-Gassing

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1.5.1.4 General Population Exposures from Environmental Releases

Environmental releases of formaldehyde are reported to occur into the ambient air, ambient water, and
land environmental media. (	)24e). General population exposures to formaldehyde occur

when individuals encounter these releases through interaction with one or more of these media (e.g.,
breathing ambient air into the body (inhalation), incidental skin contact through swimming (dermal), or
ingestion of soil (oral)).

Figure 1-7 provides a detailed conceptual model of all pathways and all routes of exposure by which
exposures to the general population may occur. While releases are reported to all three environmental
media, formaldehyde is not expected to be present in water or land based on the chemical, fate, and
transport properties of formaldehyde as described in the Draft Chemistry, Fate, and Transport
Assessment for Formaldehyde (U.	2024b) and discussed in Section 1.2.3. As such, EPA does not

expect general population exposure to formaldehyde to occur via either the water or land media and
therefore did not quantitatively assess exposures via these media in this draft risk assessment. This is
depicted in Figure 1-7 by the dashed lines.

While formaldehyde is susceptible to direct and indirect photolysis, it is expected to be present in the
ambient air for at least several hours in direct sunlight (and many more hours in no sunlight) based on
the chemical, fate, and transport properties of formaldehyde as described in the Draft Chemistry, Fate,
and Transport Assessment for Formaldehyde (	324b) and Section 1.2.3. Formaldehyde is

consistently present in ambient air based on monitoring and testing programs implemented under the
Clean Air Act and other EPA programs and statutes. Additional modeling and data from the 2019
AirToxScreen supports the ubiquity and consistent presence of formaldehyde in ambient air from
multiple sources (including TSCA and other sources). Considering these multiple lines of evidence,
EPA expects general population exposure to formaldehyde from industrial releases to be predominantly
via the ambient air pathway. Therefore, EPA quantitatively assessed the ambient air pathway in this risk
assessment. This is depicted in Figure 1-7 by a solid line.

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EXPOSURE PATHWAYS	ESPOSUKER^HES	RECEPTORS

968	Figure 1-7. Formaldehyde Conceptual Model for Environmental Releases and Wastes: General Population Exposures and Hazards

969

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Figure 1-8 provides a simplified visual representation of industrial releases to ambient air by which
exposure to the general population occurs. In general, formaldehyde is released from industrial facilities
as uncontrolled fugitive releases (e.g., process equipment leaks, process vents, building windows,
building doors, roof vents) and stack releases that may be either uncontrolled (e.g., direct releases out a
stack) or controlled with some pollution control device prior to release to the ambient air (e.g.,
baghouse, scrubber, thermal oxidizer). Once released to the ambient air, the releases move off-site into
the surrounding ambient air where exposure to the general population occurs through inhalation. For
purposes of this risk assessment, EPA focuses on formaldehyde exposures to individuals living nearby
industrial facilities associated with TSCA COUs that are releasing formaldehyde to the ambient air.

Movement of chemicals
between source(s) and media

Emissions
from
Source

Communities
near Release
Sites

Breathing Zone
Inhalation

Figure 1-8. Industrial Releases to the Environment and Pathways by Which Exposures to
the General Population May Occur

1.5,2 Potentially Exposed or Susceptible Subpopulations

This assessment considers potentially exposed or susceptible subpopulation (PESS), 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. There are many factors that may contribute to
increased exposure or biological susceptibility to a chemical, including life stage (e.g., infants, children,
pregnant women, elderly), pre-existing disease, lifestyle activities (e.g., smoking, physical activity),
occupational and consumer exposures (including workers and ONUs, consumers and bystanders),
geographic factors (living in proximity to a large industrial source of formaldehyde), socio-demographic
factors, unique activities (e.g., subsistence fishing), aggregate exposures, and other chemical and non-
chemical stressors.

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994	Considerations related to PESS may influence the selection of relevant exposure pathways, the

995	sensitivity of derived hazard values, the inclusion of populations, and/or the discussion of uncertainties

996	throughout the assessment.

997

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2 HUMAN EXPOSURE ASSESSMENT SUMMARY

This section summarizes the formaldehyde exposures to occupational workers, ONUs, consumers,
bystanders, and general population from both indoor air and ambient air. Detailed information
supporting each subsection are available in the associated technical support modules included as
supplemental files to this draft human health risk assessment for formaldehyde.

Each exposure assessment considers peak and long-term inhalation exposures. When available, the
highest 15-minute average concentrations are used to represent peak exposures while annual average
concentrations or 8-hour time-weighted averages (TWA) are used to represent longer-term exposure
durations. The long-term exposure duration depends on the exposure scenario being assessed.
Specifically, exposure durations for cancer assessment are based on 31 (central tendency) and 40 (high-
end) working years for occupational exposure. Exposure durations for cancer assessment are based on
12- or 57-year residency time and 78-year lifetime exposure for consumer and general population. Acute
dermal exposures were estimated for workers and consumers and are based on short-term durations, see
Appendix G for additional information on the dermal approaches.

Each exposure assessment integrates modeling methodologies previously peer reviewed as well as
monitoring data to assess exposures to the respective populations. The exposure assessment also
integrates information from the Draft Chemistry, Fate, and Transport Assessment for Formaldehyde
(U.S. EPA. 2024b) and the Draft Environmental Release Assessment for Formaldehyde (U.S. EPA.
2024g).

Due to the magnitude of available scientific information on formaldehyde coupled with its complex
toxicology and exposure profiles, EPA acknowledges that the evaluation of formaldehyde exposure is
challenging. The Agency is at a critical point in the development of the draft risk evaluation where
SACC and public input will be essential. For example, OPPT will seek input on its use of inputs and
assumptions in the exposure assessments for occupational, consumer, outdoor air, and indoor air
scenarios, in part to understand whether its approach may compound one conservative assumption upon
another in a manner that leads to unrealistic or un-addressable outcomes. Following SACC and public
comments, EPA will revise the draft risk evaluation and issue a final evaluation that will include a
determination of whether, under its conditions of use, formaldehyde presents unreasonable risk to health
or the environment.

2.1 Occupational Exposure Assessment

EPA identified 49 TSCA COUs under manufacturing, processing, industrial/commercial uses, and
disposal. In the Draft Occupational Exposure Assessment for Formaldehyde (	24k). EPA

evaluated occupational exposure scenarios (OESs) based on the COUs with expected worker activities,
inhalation exposure estimates, and dermal exposure estimates for each OES (U.S. EPA. 2024k). Several
of the TSCA COU categories and subcategories were grouped and assessed together into a single OES
due to similarities in the processes or lack of data to differentiate between them. This grouping
minimized repetitive assessments. In other cases, TSCA COU subcategories were further delineated into
multiple OESs based on expected differences in processes and associated releases/exposure potentials
between facilities. This resulted in assessing 36 OESs for inhalation and dermal exposure. For additional
details on the approaches and results, please refer to Draft Occupational Exposure Assessment for
Formaldehyde (U.S. EPA. 2024k).

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2,1,1 Inhalation Exposure Assessment

To assess inhalation exposures from formaldehyde, EPA reviewed workplace inhalation monitoring data
from government agencies such as Occupational Safety and Health Administration (OSHA), inhalation
monitoring data found in peer-reviewed literature, and other inhalation monitoring data submitted to
EPA. Where monitoring data were reasonably available, EPA used these data to characterize central
tendency and high-end peak (15-minute) and 8-hour TWA {i.e., full-shift) inhalation exposures for each
scenario (OES) to workers and ONUs. In some cases, EPA did not identify 15-minute peak exposure
data but identified task-based monitoring data that was used in lieu of 15-minute peak data. The quality
of the monitoring data was evaluated using the data quality review evaluation metrics and the
categorical ranking criteria described in the Draft Systematic Review Protocol Supporting TSCA Risk
Evaluation for Chemical Substances (U.S. EPA. 2021b). Relevant data were assigned an overall quality
determination of high, medium, low, or uninformative. For evidence integration, preference was given to
monitoring data sampled after the latest update of the OSHA permissible exposure limit (PEL) of
formaldehyde in 1992 to 937 |ig/m3 (0.75 ppm) and short-term exposure limit (STEL) to 2,498 |ig/m3
(2.0 ppm). This reduces uncertainties with relying on data that may not reflect current regulatory
requirements for TSCA COUs.

For many cases, EPA did not have monitoring data to estimate inhalation exposure for ONUs. In such
cases for full-shift exposures, EPA used the central tendency of worker exposure estimates. However,
EPA did not quantify peak exposures for ONUs. In general, EPA expects ONU exposures to be less than
worker exposures.

For some of the OESs, inhalation monitoring data were not identified. For these cases, EPA utilized
models including using a Monte Carlo simulation and Latin Hypercube sampling method to estimate
inhalation exposures. Where available, the EPA used generic scenarios or emission scenario documents
for relevant exposure points and model input parameters. The Agency then used either monitoring data
or modeling results to develop a high-end and central tendency estimates for short-term exposures and
8-hour TWAs for each OES.

Monitoring data were available to support exposure estimates for all COUs except for three COUs that
relied on modeled estimates:

•	Commercial use - chemical substances in automotive and fuel products - automotive care
products; lubricants and greases; fuels and related products;

•	Commercial use - chemical substances in agriculture use products - lawn and garden products;
and

•	Commercial use - chemical substances in treatment products - water treatment products.

Across TSCA COUs for peak exposure estimates, the central tendency of air concentration estimates
ranged from 86 to 2,002 |ig/m3 (0.07 to 1.63 ppm) and high-end of air concentration estimates ranged
from 86 to 237,902 |ig/m3 (0.07 to 193.7 ppm). The TSCA COU of Manufacturing showed
formaldehyde concentrations above other scenarios, with high-end and central tendency of air
concentration results of 237,902 |ig/m3 and 590 |ig/m3, respectively. The underlying scenario was based
on monitoring data from manufacturing sites within the United States, which included tasks where the
workers wore respiratory protection.

Across TSCA COUs for full-shift estimates, the central tendency of air concentration estimates ranged
from 7.5 to 499.3 |ig/m3 (0.01 to 0.40 ppm) and high-end of air concentration estimates ranged from 7.5
to 17,353.3 |ig/m3 (0.01 to 13.9 ppm). The TSCA COU of Commercial use - chemical substances in
automotive and fuel products - automotive care products; lubricants and greases; fuels and related

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products showed formaldehyde concentrations above other scenarios. The underlying scenario was
modeled using a Monte Carlo simulation and assumed that no engineering controls were present. The
first modeling approach resulted in a high-end and central tendency of air concentrations results of
17,353.3 |ig/m3 and 499.3 |ig/m3, respectively and assumes that formaldehyde within the automotive
care product is completely evaporated during duration of application. This results in a very conservative
high-end estimate, well above the current OSHA PEL. EPA also used a second modeling approach using
industry monitoring data on total volatile organic compounds to estimate 1,874 |ig/m3 and 371 |ig/m3.

EPA uses peak exposure concentration estimates to calculate acute exposure concentrations (AECs),
which is used to estimate acute, non-cancer risks. The full-shift (8- or 12-hour TWA concentrations) are
used to calculate average daily concentrations (ADCs) and lifetime average daily concentrations
(LADCs). The ADC is used to estimate chronic, non-cancer risks and the LADC is used to estimate
chronic, cancer risks. These calculations required additional parameter inputs, such as years of exposure
(31 or 40 year worker tenure), exposure duration and frequency (167 or 250 days), and lifetime years
(78 years). See Appendix F for more information about parameters and equations used to calculate acute
and chronic exposures.

2.1.2 Dermal Exposure Summary	

Dermal exposure data were not reasonably available for any of the formaldehyde OESs. Therefore, the
EPA modeled dermal exposure to workers using a modified version of the EPA Dermal Exposure to
Volatile Liquids Model. As the health effect of concern for formaldehyde is the result of exposure at the
point of contact, as opposed to the chemical absorbing into the skin, the absorption factor, body weight,
and surface area were not necessary for the calculation of dermal exposure. The calculation reduces to
an assumed amount of liquid on the skin during one contact event per day adjusted by the weight
fraction of formaldehyde in the liquid to which the worker is exposed.

EPA only evaluated dermal exposures for workers since ONUs are not assumed to directly handle
formaldehyde. EPA did not quantify dermal exposure for two COUs: Distribution in commerce and
Commercial use - chemical substances in packaging, paper, plastic, hobby products - paper products;
plastic and rubber products; toys, playground, and sporting equipment as dermal contact was expected
with solid articles that may contain low residual formaldehyde concentrations.

EPA used the maximum formaldehyde concentrations, which is the highest concentration level of
formaldehyde that a worker handles throughout the process. EPA used concentration data from
published literature and CDR to develop high-end and central tendency dermal exposure estimates.

The dermal exposure estimates ranged from 0.56 to 840 |ig/cm2 for central tendency exposures, and 0.84
to 3,090 |ig/cm2for high-end exposures. The high-end dermal retained dose for four COUs had a value
of 3,090 |ig/cm2, which is well above the other dermal exposure estimates:

•	Commercial use - chemical substances in automotive and fuel products - automotive care
products; lubricants and greases; fuels and related products and

•	Processing - incorporation into an article - paint additives and coating additives not described by
other categories in transportation equipment manufacturing [including aerospace];

•	Industrial use - paints and coatings; adhesives and sealants; lubricants; and

•	Commercial use - chemical substances in construction, paint, electrical, and metal products -
adhesives and sealants; paint and coatings.

For manual spray applications, EPA expects dermal exposures to be higher. Spray applications are
expected for the use of automotive care products and coatings, paints, adhesives, or sealants. In addition,

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during the use of automotive care products, workers may use immerse rags in the detailing products,
which could lead to higher dermal loading. For both OESs, EPA assumed an immersive dermal loading
(HE: QR of 10.3 mg/cm2) on the skin during the exposure scenario. For other OESs, EPA calculated
dermal exposures assuming lower dermal loadings based on expected worker activities (HE: Qu of 2.1
mg/cm2).

2.2 Consumer Exposure Assessment

To assess consumer exposures, EPA identified 30 exposure scenarios (from 12 formaldehyde TSCA
COUs) that may lead to consumer or bystander exposures. EPA's Consumer Exposure Model (CEM)
Version 3.0 was used to estimate the 15-minute peak and lifetime average daily concentration for
inhalation exposures to consumer users and bystanders, and the dermal loading during relevant product
and article use. The key conclusions of the consumer exposure assessment are summarized in the CEM
(I	I024d) and below.

EPA only quantified exposures for plausible exposure pathways, routes, and timespans of exposure and
exposure scenarios for which EPA had at least a medium level of confidence. This means that for some
COUs (i.e., solid products) a dermal loading estimate was not generated since it was not deemed
appropriate (e.g., dermal loading from machinery, mechanical appliances, electrical/electronic articles)
given the best available tools and data. This also means that the total number of COUs assessed for acute
and chronic inhalation scenarios (e.g., 15-minute peak compared to lifetime average daily concentration
estimations) varied according to the relevance of the exposure assessment. However, as presented in
Table 1-1 of the Draft Consumer Exposure Assessment for Formaldehyde (	)24d). EPA

quantified exposures for all relevant COUs for at least one route of exposure.

Of note, when potential exposures to the machinery, mechanical appliances, electrical/electronic articles
were assessed, CEM did not yield any expected inhalation exposures via estimates of 15-minute peak
and average daily concentration. Modeled estimates for adhesives and sealants were used as surrogates
for the exposures to electronic products because adhesives and sealants are used in the binding of
internal components and especially at the seams of electronic products. Similarly, EPA does not expect
dermal (skin loading) or oral exposures from reasonably foreseen use of such products, as these
exposures are expected to be negligible.

In addition, EPA did not quantify exposures for COUs in which EPA had a low exposure assessment
confidence. EPA did, however, qualitatively assess the following COUs:

•	Water treatment products: No supporting products could be identified other than a fish tank
cleaning solution and because formaldehyde is highly reactive in water; therefore, these
exposures are expected to be negligible.

•	Laundry and dish washing products: Formaldehyde is highly reactive in water. EPA believes
these preliminary CEM modeling results are implausible.

•	Lawn and garden products: The non-pesticidal exposure scenario for this TSCA COU is unclear
because when mixed in water, formaldehyde is highly reactive. In addition, EPA's CEM
assumes no inhalation exposure from such products. This is likely due to the default assumption
that such activities typically occur outdoors where the chemical would be diluted in the ambient
air during and after use.

•	Foam insulation: Formaldehyde exposures from foam insulation products were not quantified as
consumer exposures to these products are expected to be minimal. During the public comment
period for the draft high priority designation of formaldehyde, the North American Insulation
Manufacturers Association stated "for those insulation products in which formaldehyde is a

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component of the binder, the products are cured at high temperatures during the manufacturing
process after the binder has been applied, virtually eliminating the free formaldehyde content.
Any free formaldehyde released from the binder during cure is destroyed either during the cure
process or by emissions control equipment required by the Maximum Achievable Control
Technology (MACT) standard. Therefore, formaldehyde off-gassing from the majority of
finished products is highly unlikely" (Docket < 1 * < \ HQ-OP < I _*-«l l). Given this
information, EPA expects formaldehyde exposures to foam insulation to be negligible.

Given that each TSCA COU may comprise multiple exposure scenarios and multiple scenarios may be
applicable to multiple COUs, representative scenarios were identified for each TSCA COU per relevant
exposure assessment. Representative scenarios were identified according to the highest estimated
exposure estimate per assessment. Refer to Appendix B of the Draft Consumer Exposure Assessment for
Formaldehyde (	) for a list of representative consumer exposure scenarios according to

TSCA COUs.

CEM uses a two-zone representation of the building of use when predicting indoor air concentrations.
Zone 1 represents the room where the consumer product is used; Zone 2 represents the remainder of the
building. Each zone is considered well-mixed. CEM allows further division of Zone 1 into a near-field
and far-field to accommodate situations where a higher concentration of product is expected very near
the product user when the product is used. Zone 1-near-field represents the breathing zone of the user at
the location of the product use while Zone 1-far-field represents the remainder of the Zone 1 room.

Inhalation exposure is estimated in CEM based on zones and pre-defined activity patterns. The
simulation run by CEM places the product user within Zone 1 for the duration of product use while the
bystander is placed in Zone 2 for the duration of product use. Following the duration of product use, the
user and bystander follow one of three predefined activity patterns established within CEM, based on
modeler selection. The selected activity pattern takes the user and bystander in and out of Zone 1 and
Zone 2 for the period of the simulation. The user and bystander inhale airborne concentrations within
those zones, which will vary over time, resulting in the overall estimated exposure to the user and
bystander.

Modeled formaldehyde concentrations depend upon the room of use, amount of the chemical in the
product and consumer use patterns (e.g., amounts used). Consumer users of products and articles
generally had higher peak and long-term inhalation exposures, in comparison with bystanders. Across
all relevant age groups and exposure scenarios, the highest estimated 15-minute peak TWA
formaldehyde air exposure was for consumer users of floor coverings; foam seating and bedding
products; cleaning and furniture care products; furniture & furnishings including stone, plaster, cement,
glass and ceramic articles; metal articles; or rubber articles, while the lowest 15-minute peak exposure
was for individuals using textiles or clothing that emit formaldehyde (Figure 2-1). Consumer users of
adhesives and sealants; paint and coatings were estimated to have the highest estimated average daily air
exposure to formaldehyde (Figure 2-2), while consumer users of automotive care products had the
lowest average daily exposure.

The highest acute dermal loading for consumer users resulted from use of automotive care products. The
lowest acute dermal loading resulted from use of arts, crafts, and hobby materials (Figure 2-3). For the
dermal assessment, the estimated dermal loading was based on weight fraction identified in the literature
and safety data sheets (SDSs).

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Floor coverings; Foam seating and bedding
products; Cleaning and furniture care products;
Furniture & furnishings including stone, plaster,
cement, glass and ceramic articles; metal
articles; or rubber articles

Adhesives and Sealants; Paint and coatings -

Paper products; Plastic and rubber products; Toys, _
playground, and sporting equipment

D

o
o

Ink, toner, and colorant products; Photographic,

supplies

Construction and building materials covering
large surface areas, including wood articles;
Construction and building materials covering
large surface areas, including paper articles;
metal articles; stone, plaster, cement, glass and

ceramic articles

Automotive care products; Lubricants and greases;

Fuels and related products

Fabric, textile, and leather products not covered
elsewhere (clothing)

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1235

+

• A

+

+

Zone
• Far Field
a Near Field
¦ Zone 1
+ Zone 2

1CT

10

Peak 15-min Concentration ((jg/m3)

Figure 2-1. Summary of 15-Minute Peak Consumer Inhalation Concentrations (Based on CEM)

For some products, air concentrations were modeled for near-field and far-field (generally describing differences in exposure within the same room), while
for other products, concentrations were modeled for zones 1 and 2 (generally describing different rooms). Risks from near-field and zone 1 exposures
generally represent risks from direct exposures to consumer users while far-field and zone 2 tend to represent risks to consumer bystanders. The x-axis
presents the 15-minute peak inhalation non-cancer concentration and the y-axis presents the modeled TSCA COU.

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Adhesives and Sealants; Paint and coatings -

Arts Crafts and Hobby Material

Z)
O
O

Ink, toner, and colorant products; Photographic_

supplies

Floor coverings; Foam seating and bedding
products; Cleaning and furniture care products;
Furniture & furnishings including stone, plaster,
cement, glass and ceramic articles; metal
articles; or rubber articles

Automotive care products; Lubricants and greases;

Fuels and related products

1236

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1238

O

O

o

~

o

Modeled Person
~ Bystander
O User

O

_L

1	10

Average Daily Concentration (|jg/m3)

100

Figure 2-2. Summary of Average Daily Consumer Inhalation Concentrations, per Year (Based on CEM)

The x-axis presents the chronic inhalation average daily concentration, and the y-axis presents the modeled exposure TSCA COU.

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Polish and wax - (Exterior Car Wax and

Polish)

Photographic Supplies - (Liquid photographic
processing solutions)

o Cleaning and Furnishing Care Products -
(Drain and Toilet Cleaners)

c

0
o
w

T3

0
¦o

o	Adhesives and Sealants - (Glues and

^	Adhesives, small or large scale)

Building / Construction Materials - (Liquid-
based concrete, cement, plaster (prior to

hardening))

Arts, Crafts, and Hobby Materials - (Crafting
Paint (direct and incidental contact))























































Modeled
Exposure Level

~ High



—	

—-

	

1—

1 1 1

101	102	103

Acute Dermal Loading Concentration (pg/cm2)

Figure 2-3. Summary of Acute Consumer Dermal Concentrations (Based on Thin Film Model)

The x-axis presents dermal loading concentration, and the y-axis presents the modeled TSCA COUs. The term
"High" in the figure refers to high-end scenarios as described above.

2.3 Indoor Air Exposure Assessment	

A detailed analysis for indoor air can be found in the Draft Indoor Air Exposure Assessment for
Formaldehyde (U.S. EPA. 2024i). The separation of the consumer exposure assessment and the indoor
air exposure assessment is intentional; each assessment represents a different context of exposures.
Generally, exposures to most consumer products occur over a relatively short period of time (minutes to
hours per day) and the duration of exposure from those uses within a residence are expected to be short
relative to continuous sources of exposure such as flooring or furniture. Thus, the indoor air exposure
assessment represents exposures mainly resulting from the presence of articles or materials within a

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residential household which typically off-gas formaldehyde over an extended period (particularly the
first several years after an article or material is manufactured). The indoor air exposure assessment also
incorporates aspects of ongoing exposures to populations in office or commercial settings and therefore
is more expansive and inclusive than the consumer exposure assessment.

Formaldehyde is a chemical ingredient in many products, which release formaldehyde into the indoor
air. Indeed, indoor air studies of formaldehyde S. 2002; AT SDK I' !')_9) demonstrate that the indoor
environment, including homes and automobiles, can be a major source of formaldehyde exposure. This
is because formaldehyde is used ubiquitously for the manufacturing of various consumer products (e.g.,
wallpaper, hardwood floors, seat covers used in numerous articles) and because formaldehyde is formed
as a combustion byproduct from sources such as fireplaces, ovens, stoves, and tobacco smoke.

Given the number of TSCA and other sources contributing to formaldehyde in indoor air, indoor air
concentrations reported in monitoring studies are generally considered a reflection of aggregate
exposures. Any reported average indoor air monitoring for formaldehyde in American homes is
expected to be a result of off-gassing from articles or materials, or long-term emissions (e.g., from
fireplaces or stoves), from multiple TSCA COUs and other sources. While intermittent product or article
use may briefly contribute to indoor air formaldehyde concentrations, generally EPA assumes that most
formaldehyde indoor air exposures occur over an extended period spanning several months to multiple
years (	j).

In the Draft Indoor Air Exposure Assessment for Formaldehyde (U.S. EPA. 2024i\ EPA considered
available monitoring data from commercial, residential, and automobile environments (Section 2.3.10).
EPA also used CEM to model chronic indoor air exposure resulting from TSCA COUs that are expected
to be the largest contributors of formaldehyde to indoor air primarily due to off-gassing (Section 0).
EPA incorporated TSCA COU-specific emission rates extracted from the literature, when available, into
its modeling to better approximate real-world conditions. Residential indoor air modeled and measured
concentrations of formaldehyde were generally within the same order of magnitude.

2,3.1 Indoor Air Exposure Monitoring Results

EPA identified over 800 monitoring studies, 290 of which are specific to the indoor air environment and
associated with the 12 TSCA COUs subject to this risk evaluation (see Appendix A of the Draft Indoor
Air Exposure Assessment for Formaldehyde (	24iV). As was presented in Section 3.2.2 of

the 2016 Formaldehyde Exposure Assessment Report TSCA Title VI Final Rule (U.S. EPA. 2016b). EPA
presents a supplemental summary of formaldehyde concentrations identified from several well-
established residential (Table 2-1, Figure 2-4) and commercial (Table 2-2) indoor air monitoring studies
to provide additional context to the TSCA formaldehyde indoor air exposure assessment. From a
comparison of residential (Table 2-1) and commercial (Table 2-2) indoor air monitoring, residential
indoor air exposures to formaldehyde are generally expected to be higher compared to commercial
buildings due to expected lower room volumes and air exchange rates in residences relative to
commercial buildings.

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1291 Table 2-1. Indoor Air Monitoring Concentrations for Formaldehyde

Reference

Monitoring Study Description

Formaldehyde Concentrations (jig/m3)

Central Value

Range/Percentiles

American Healthy
Home Survey
(OuanTech. 2021)

Nationally representative sample of
688 U.S. homes of various ages,
types, conditions, and climates

Mean: 23.2

Range (lower/upper 95% tiles
of mean): 21.4-25.0



(GARB. 2004)

Portable and traditional classrooms in
67 California schools (Phase II study)

Arithmetic mean:
18.42 (portable)
14.74 (traditional)

95th Percentile:
31.93 (portable)
27.02 (traditional)



("Gilbert et ah.

59 homes in Prince Edward Island,
Canada

Geometric mean:
33.16

Range:
5.53-87.33

2005)

(Gilbert et aL

96 homes in Quebec City, Canada

Geometric mean:
29.48

Range: 9.58-89.91

2006)

(Hodgson et aL,

4 new relocatable classrooms

Unspecified mean:
9.83 (indoor-
outdoor)

Range:

4.91-14.74 (indoor-outdoor)

2004)

(Hodgson et aL,

New homes in eastern/SE U.S.:
4 new manufactured homes
7 new site-built homes

Geometric mean:

41.76

44.22

Range:

25.79-57.73

17.2-71.24

2000)

(Liu et aL. 2006)

234 homes in Los Angeles County,
CA; Elizabeth, NJ; and Houston, TX

Median:
20.02

Range:

12.53-32.43
(5th-95th percentiles)



(LBNL. 2008)

4 FEMA camper trailers

Unspecified mean:
568.67

Range:

330.39-924.85



(Mtirollv et aL.

Sample:

All structures (519)
Travel trailers (360)
Park models (90)
Mobile homes (69)

Geometric mean:

94.57

99.49

54.04

70.01

Range:

3.68-724.65

3.68-724.65

3.68-196.52

13.51-393.03

2013)

(Offermann et aL.

108 new SF homes in CA

Median:
38.2

Range:
4.67-143.33

2008)

(Sax et aL, 2004)

Inner-city homes:

NY City (46) - winter (W), summer

(S)

Los Angeles (41) - winter (W), fall
(F)

Median:

12.28 (W), 18.42 (S)
18.42 (W), 14.74 (F)

Range:

4.91-22.11 (W), 6.14-50.36
(S)

7.37-55.27 (W), 7.37-31.93
(F)



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1293 Table 2-2. Formaldehyde Monitored in U.S. Commercial Buildings from 2000 to Present

Reference

Monitoring Study Description

Formaldehyde
Concentrations
(jig/m3)

Descriptor

(Ceballos and

Office space indoor air monitoring for
formaldehyde in a commercial building

24.56

Average

Burr. 2012)

ru.s. EPA.

Indoor air monitoring across 100
randomly selected U.S. commercial
buildings

3.68

5th percentile

2023k)

14.74

50th percentile

30.71

95th percentile

(Page and Couch.

Indoor air U.S. government offices

<61.41

Maximum

2014)

(Lukcso et al..

12.28

Geometric mean

2014)

56.50

Maximum

(Dodson et al..

Classrooms in school buildings in the
United States

17.69

Median

2007)

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Monitoring data from the American Healthy Homes Survey II suggests that concentrations of
formaldehyde may range from 0.27 to 124.2 |ig/m3 for all homes (including new homes at the time of
survey), with 95 percent of homes having concentrations below 47 |ig/m3 (OuanTech. 2021). Those data
include formaldehyde produced from both TSCA sources (Section 3.1.1 of th q Draft Indoor Air
Exposure Assessment for Formaldehyde (	24\) and other sources of formaldehyde such as

tobacco smoke or the use of fireplaces, gas-burning appliances, candles, and air purifiers (OuanTech.
2021). These other sources do not contain formaldehyde but rather lead to the formation of
formaldehyde during use.

For other sources of formaldehyde in indoor air, simulated 50th percentile room concentrations ranged
from 12.3 to 44.2 [j,g/m3 individually for candles, incense, cooking, wood combustion, and air cleaning
devices, and up to 152.2 [j,g/m3 for ethanol fireplaces (ECHA. ^ ). Air cleaning devices such as
photocatalytic air purifiers can produce formaldehyde from irradiation of air contaminants, leading to
increased indoor air concentrations of formaldehyde (Salthammer. 2019). Formaldehyde production
associated with cooking depends on many factors, including cooking temperature and type of oil and
variety of food being cooked. Select gas-oven cooking tests involving a variety of cooking parameters
resulted in formaldehyde concentrations ranging from 36.5 to 417.3 [j,g/m3 (Salthammer. 2019). Tobacco
smoke is also known to be a contributor to formaldehyde concentrations within all indoor air
environments (U.S. EPA. 2016b; Girman et ai. 1982). although according to the World Health
Organization, tobacco smoke primarily increases formaldehyde concentrations in indoor air
environments where the rates of smoking are high with minimal ventilation ( S. 2002).

2.3.2 Indoor Air Exposure Modeling Results

EPA used CEM to model indoor air concentrations in American homes and vehicles based on TSCA
COU-specific emission rates, providing an estimate of TSCA COU-specific contributions to
formaldehyde in indoor air. Central tendency estimates were generated as discussed in Section 2.1.1.1.3
of the Indoor Air Exposure Module (	Z024i) for comparability with AHHS II monitoring data

and to estimate common indoor air concentrations for most American households. For the TSCA COUs
identified in Section 1.1 of the Indoor Air Exposure Module (	024i). EPA estimated chronic

average daily indoor air exposures. Through a review of key products known to be significant and
persistent emitters of formaldehyde, EPA identified four TSCA COUs as potentially significant
contributors to residential indoor air environment.

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Construction and building materials covering
large surface areas, including wood articles;
Construction and building materials covering
large surface areas, including paper articles;
metal articles; stone, plaster, cement, glass and

ceramic articles

Floor coverings; Foam seating and bedding
products; Cleaning and furniture care products;
Furniture & furnishings including stone, plaster,
cement, glass and ceramic articles; metal
articles; or rubber articles

Z)
O
O

Paper products; Plastic and rubber products; Toys,
playground, and sporting equipment

Fabric, textile, and leather products not covered

elsewhere

Environment

Residential

_1	I	L_

X

4-

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1332

101	10

Chronic Average Daily Concentration (jjg/m3)

Figure 2-5. Modeled Formaldehyde Average Daily Inhalation Concentrations in Indoor Air (According to CEM)

The x-axis presents the average daily concentration, and the y-axis presents the modeled TSCA COUs.

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EPA generated estimated indoor air exposures using the CEM for four TSCA COUs (see Section 2.1.1
of the Indoor Air Exposure Module (	E024iV). The Agency used emission rates and fluxes

identified from the literature and compared the estimated indoor air concentrations in homes and
vehicles with air monitoring concentrations from the literature (Table 2-3 of the Indoor Air Exposure
Module (U .S. EPA. 2024iV). Modeled concentrations of formaldehyde are within the same order of
magnitude as reported in monitoring studies, including the American Healthy Homes Survey II (see
Section 3.2 of the Indoor Air Exposure Module (U.S. EPA. 2024iV).

The estimated formaldehyde indoor air exposures likely represent exposures from new articles added to
a resident (e.g., wood products). Given each COU may comprise multiple exposure scenarios and
multiple scenarios may be applicable to multiple COUs, representative exposure scenarios were
identified according to the highest estimated exposure estimate per scenario in a room of use, for each
COU (Table 2-3).

Table 2-3. Representative Residential Indoor Air Exposure Scenarios According to COUs

Conditions of Use

CEM Exposure Scenarios"

Construction and building materials covering large surface areas,
including wood articles; Construction and building materials covering
large surface areas, including paper articles; metal articles; stone, plaster,
cement, glass and ceramic articles

Building/Construction
Materials - Wood Articles:
Hardwood Floors (residential)

Fabric, textile, and leather products not covered elsewhere

Seat Covers (automobile)

Furniture Seat Covers
(residential)

Fabrics: Clothing (residential)6

Floor coverings; Foam seating and bedding products; Cleaning and
furniture care products; Furniture & furnishings including stone, plaster,
cement, glass and ceramic articles; metal articles; or rubber articles

Furniture & Furnishings -
Wood Articles: Furniture
(residential)

Paper products; Plastic and rubber products; Toys, playground, and
sporting equipment

Paper-Based Wallpaper
(residential)

"Representative exposure scenarios, as noted in Section 2.1.1, are bolded as these scenarios had the highest
estimated concentrations per COU.

h Within this COU, the Clothing (residential) scenario is identified as the representative scenario despite a lower
estimated concentration compared to Seat covers (automobile), since residential indoor air environments are of
primary interest in this indoor air assessment.

Over the span of a year, the highest TSCA COU contributor to the residential indoor air environment
was building wood products. Additionally, while several of the modeled COUs may occur
simultaneously, aggregating exposures for all four TSCA COUs may not be reflective of actual exposure
scenarios encountered over a lifetime as the combination of these TSCA COU likely differ from home to
home and overtime. Additionally, while several of the modeled COUs may occur simultaneously,
aggregating exposures for all four TSCA COUs may not be reflective of actual exposure scenarios
encountered over a lifetime because the combination of these TSCA COUs likely differ both from home
to home and over time.

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2.3.2.1 Aggregate Indoor Air Exposure

EPA defines aggregate exposure as "the combined exposures to an individual from a single chemical
substance across multiple routes and across multiple pathways (40 CFR § 702.33)." Theoretically, the
reported formaldehyde concentrations from the monitoring data may represent aggregate formaldehyde
indoor air concentrations in vehicles per the Lawryk et al. study (Lawrvk and Weisel. 1996; Lawrvk et
ai. 1995) and across U.S. households per the AHHS II study (OuanTech. 2021). assuming at least a 3-
hour TWA; or the typical indoor air concentration of formaldehyde in these environments.

EPA considered aggregating modeled air concentrations for plausible combinations of COUs expected
to co-occur in specific indoor air environments (e.g., combinations of products likely to be present in
mobile homes, new homes or automobiles), but concluded that, due to variability among homes and over
time within a given home, uncertainties were too great to support a quantitative aggregate analysis
across multiple COUs.

2.4 Ambient Air Exposure Assessment

The ambient air exposure assessment for formaldehyde quantitatively evaluates exposures resulting
from industrial releases of formaldehyde to ambient air that are associated with TSCA COUs. This
assessment focuses on a subset of the general population who reside near releasing facilities by utilizing
both modeling approaches and ambient monitoring data to assess and characterize ambient air
concentrations and exposures to formaldehyde. A detailed summary of all the analyses conducted,
methodologies used, and all exposure concentration results for formaldehyde are provided in the Draft
Ambient Air Exposure Assessment for Formaldehyde (	1024a) and associated supplemental

files.

2.4,1 Monitoring for Ambient Air Concentrations

EPA identified and summarized monitoring data for formaldehyde from EPA's Ambient Monitoring
Technology Information Center (AMTIC) (U.S. EPA. 2022a). The Agency also identified and
summarized outside monitoring data during EPA's systematic review process (	023a). These

results are presented in the Draft Ambient Air Exposure Assessment for Formaldehyde (U.S. EPA.
2024a).

This assessment summarizes monitoring data from EPA's AMTIC (	322a)to understand

aggregate or total formaldehyde concentrations in ambient air. The AMTIC data are also used to
characterize modeled concentrations of formaldehyde with recognition of the differences between these
information sources. That is, modeled environmental concentrations only include releases that can be
associated with TSCA COUs while monitoring data does not differentiate between concentrations
associated with TSCA COUs and concentrations from all other sources. These differences can limit
direct comparison, although EPA conducted some analyses to inform specific local impacts where both
modeled and monitored ambient air concentrations are available based on locations of monitoring sites
and industrial facilities releasing formaldehyde to the ambient air.

The AMTIC dataset for formaldehyde includes 195 monitoring sites from 36 different states. Data were
extracted across 6 years (2015 through 2020) and include a total of 306,529 observations. EPA
calculated summary statistics for all samples, samples by state, samples by census tract, samples by
monitoring site, samples by monitoring site and year, and samples by monitoring site and year and
quarter. For purposes of this ambient air exposure assessment, EPA used the overall statistics across all
samples to characterize exposures and characterize exposures to the general population (Table 2-4).
Monitoring locations and annual summary statistics are provided in the ambient air exposure module
(	2024a).

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The last 5 years of available AMTIC data were selected for use in the formaldehyde assessment. (2015
to 2020). This dataset includes a total of 233,961 entries for formaldehyde within the five-year duration
from 20 air monitoring programs covering 32 states within the contiguous United States. Any entries
with missing key data were omitted from the analysis (e.g., concentrations, concentration units, method
detection limits, methodology used). All concentration and method detection limit (MDL) values were
converted to micrograms per cubic meter (|ig/m3) for unit uniformity between submitting programs.
Method detection limits were provided along with sample concentrations on a submission-by-
submission basis by submitting agencies, from 0.000011 to 1.2 |ig/m3, and varied by sample based on
the sampling and analysis methodology. Entries with reported concentrations below the method
detection limit were substituted with a value of 0 |ig/m3. Concentrations of formaldehyde ranged from
below the method detection limit to 60.1 |ig/m3 and a median value of 1.6 |ig/m3. A summary of the
statistics extracted from the overall dataset are provided in Table 2-4.

Table 2-4. Overall Monitored Concentrations of Formaldehyde from AMTIC Dataset

Monitored Concentrations (jig/m3)

Aggregation

Count

Minimum

Minimum
(non-zero)

Median

Mean

Maximum

All Entries

233,961

0

0.002

1.6

2.1 ±2.2

60

Daily Mean

3,843

0

0.011

2.5

3.0 ± 2.0

18.4

Annual Mean

64

1.4

1.4

2.9

3.0 ± 1.1

6.5

The individual site data collected by AMTIC represents various sampling techniques sample collection
duration ranging from 5 minutes to 24 hours. When using these data for comparison to the presented
formaldehyde models, the concentrations were converted to daily and annual averages. AMTIC
concentration values were used to calculate daily or annual average only when there was greater than 75
percent sample coverage over the averaged timeframe when converting from sub-hour samples to hourly
averages and again for hourly samples to daily averages. Each annual quarter required a minimum of
seven valid daily averages and each annual mean required a minimum of three valid quarterly averages
per year per site. The high standards for coverage resulted in a drastic reduction in the data available for
conversion to daily and annual averages. Of the original 233,961 complete entries, there were 64 site-
years and 3,843 site-days with sufficient coverage to calculate daily and annual average statistics (Table
2-4). EPA is investigating additional methods under OAR guidance to better estimate daily and annual
average statistics to increase the number of available sites and data available for use in model
comparison.

2.4.2 Modeling Ambient Air Concentrations

2.4.2.1 Integrated Indoor/Outdoor Air Calculator Model (IIOAC)

EPA used the Integrated Indoor-Outdoor Air Calculator (IIOAC) Model to estimate daily- and annual-
averaged formaldehyde concentrations for a suite of exposure scenarios at three predefined distances
from a facility releasing formaldehyde to the ambient air. EPA's modeling evaluated industrial releases
of formaldehyde that are associated with COUs from two separate databases (TRI and NEI). EPA
compared releases and modeled concentrations from the two databases and found results were within the
same estimated distribution range. Therefore, to provide a clearer picture of findings, the Agency only
presents results from the TRI dataset in this draft human health risk assessment. Nonetheless, results
from all exposure scenarios and datasets evaluated are provided in the "Draft Ambient Air Exposure
Assessment Results and Risk Calcs Supplement A."

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EPA utilized the 95th percentile release value reported to TRI by Industry Sector (mapped to respective
TSCA COUs) and the 95th percentile modeled daily-averaged and annual-averaged air concentrations
from the IIOAC output file at a distance of 100 to 1,000 m from the release facility to characterize
exposures and derive risk estimates (see Section 4.2.4.2). Additionally, the exposure scenario used for
this Draft Human Health Risk Assessment assumes an industrial facility releasing formaldehyde to the
ambient air operates 24 hours/day, 7 days/week, 365 days/year, which is likely a conservative
assumption.

The 95th percentile release scenario and modeled concentrations were used to represent a more national
level exposure estimate based on actual reported releases. The operating scenario was selected because it
is representative of typical operating conditions under which industrial facilities involved with
formaldehyde manufacturing, processing, etc. operate. Although this scenario is representative of a high-
end exposure scenario that is inclusive of more sensitive and locally impacted populations, it is not a
maximum worst-case exposure scenario and thus considered more representative of an overall
community or nationally representative exposure scenario.

Because of the exposure scenario used (365 days per year, 24 hrs/day, 7 days per week), the daily-
averaged modeled concentration and annual-averaged modeled concentration output values from the
IIOAC Model are the same. Results from this exposure scenario are summarily presented independently
in the "Draft Ambient Air Exposure Assessment Results and Risk Calcs Supplement B." The reason for
the same modeled concentrations is a math exercise based on the way annual-averaged concentrations
are calculated as an arithmetic average of all daily-averaged concentrations. If the daily-averaged
concentrations are based on 365 days of exposure, then the annual average will be the average of the
same values and result in the same modeled concentration. However, EPA also ran 250 days of exposure
(although not presented here, modeled concentrations are included in the supplemental files), and for
this 250-day exposure scenario, the daily-averaged and annual-averaged concentrations are different.
The reason for that is the annual-averaged concentrations will also include zero concentration days, and
therefore result in a different arithmetic average of the daily modeled concentrations.

Results for acute and chronic exposures across all industry sectors and associated COUs ranged from
0.0001 to 5.7 |ig/m3 for the exposure scenario described above. Results are presented for each TSCA
COU in Figure 2-6. These results represent the highest exposure concentration across all industry sectors
associated with the respective formaldehyde TSCA COU. The presented results also represent both the
acute and chronic exposure concentrations, which are the same, as described above. Additional details
on these results, including the industry sectors with the highest estimated exposure concentrations and
associated TSCA COUs are provided in the Draft Ambient Air Exposure Assessment for Formaldehyde
(U.S. EPA. 2024aY

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1483

Processing as a reactant-lntermediate
Processing-Repackaging
Processing-Recycling
Processing-Reactant-intermediate
Processing-Reactant-Bieaching Agent
Processing-Reactant-Adhesive and Sealant Chemicals
Processing-Incorporation into Article-Finishing Agents
Processing-Incorporation into article-Adhesive and sealants
Processing-Incorporation into Article-Additive
Processing-Incorporation into an Article-Paint additives and coating additives
Processing-Incorporation into a formulation, mixture, or reaction product-Surface Active Agents
Processing-Incorporation into a formulation, mixture, or reaction product-Solvents (which become part of a product formulation or mixture)

Processing-Incorporation into a formulation, mixture, or reaction product-Solid separation agents
Processing-Incorporation into a formulation, mixture, or reaction product-Processing aids, specific to petroleum production
Processing-Incorporation into a formulation, mixture, or reaction product-Plating agents and surface treating agents
Processing-Incorporation into a formulation, mixture, or reaction product-Paint additives and coating additives not described by other categories

Processing-Incorporation into a formulation, mixture, or reaction product-Lubricant and lubricant additive
Processing-Incorporation into a formulation, mixture, or reaction product-Ion exchange agents
Processing-Incorporation into a formulation, mixture, or reaction product-Intermediate
Processing-Incorporation into a formulation, mixture, or reaction product-Bleaching Agents -
Processing-Incorporation into a formulation, mixture, or reaction product-Agricultural chemicals (Nonpesticidal) -
Processing-Incorporation into a formulation, mixture, or reaction product-Adhesive and Sealant Chemicals -

Processing- Incorporation into a formulation, mixture, or reaction product -

Manufacturing-Importing -
Industrial Use-Non-incorporative activities-Used in: construction -
Industrial Use-Non-incorporative activities-Oxidizing/reducing agent; processing aids, not otherwise listed -
Industrial Use-Chemical substances in industrial products-Paints and coatings; adhesives and sealants, lubricants -

Domestic Manufacturing -
Disposal -

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Concentration (|jg/m3)

Figure 2-6. Exposure Concentrations by TSCA COli for the 95th Percentile Release Scenario and 95th Percentile Modeled
Concentration between 100 and 1,000 in from Industrial Facilities Releasing Formaldehyde to the Ambient Air

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2.4.2.2 AirToxScreen

EPA used 2019 AirToxScreen to understand the relative contributions of other sources to overall
formaldehyde concentrations in the ambient air. AirToxScreen is an EPA screening tool used to evaluate
air toxics from all known sources across the United States and estimates air concentration and associated
health risk at the census tract level nationwide using a combination of models and data sources (Scheffe
et ai. 2016). For formaldehyde specifically, AirToxScreen integrates atmospheric chemistry for
predicting the production and decay over larger extents using the Community Multiscale Air Quality
(CMAQ) model (Luecken et ai. 2019). The 2019 AirToxScreen data are shown in Figure 2-7. The
figure shows the range of concentrations across all sources of formaldehyde, as well as contributions
from biogenic sources, secondary sources, and point sources.

Secondary production of formaldehyde is the largest contributor of formaldehyde to ambient air with
modeled concentrations ranging from 0.085 to 1.8 |ig/m3 (mean ± 1SD: 0.86 ± 0.25 |ig/m3) according to
the AirToxScreen data. Secondary production is the atmospheric formation of formaldehyde from
natural and manmade compounds. This can include the degradation of isoprene (a compound naturally
produced by animals and plants) to formaldehyde and other complex air chemistry. AirToxScreen is not
able to apportion the relative contributions from different secondary sources (source apportion).

Biogenic sources also have a higher contribution to total concentration with a range of 0.0014 to 0.67
|ig/m3 (mean ± 1SD: 0.13 ± 0.072 |ig/m3) based on the AirToxScreen data. Biogenic sources include
those emissions from trees, plants, and soil microbes.

It is noteworthy that the AirToxScreen data cannot be attributed to COUs but do show relative
distributions of various sources. The point source estimates; however, are expected to include
contributions from COUs. Point sources contributions to total formaldehyde concentrations range from
0.0 to 0.88 |ig/m3 (mean ± 1SD: 0.0070 ± 0.014 |ig/m3). However, as described above, the
AirToxScreen data are averaged across census tracts, which can result in a considerable underestimation
of exposures relative to a source-specific contribution to which populations living nearby releasing
facilities are exposed and thus not comparable to the modeled concentrations from IIOAC.

Figure 2-7 does not include AirToxScreen data for on-road sources, near-road sources, off-road sources,
wildfire sources, etc. However, these sources would be captured in the results shown for all sources.

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All Sources

Secondary
Production

Point
Sources

Biogenic
Sources

Legend

25lh Percentile 75th Percentile















	mmm •











' I" "1	' ' ¦ I ""1	' ' 'I "ill	i i i !¦¦¦]	i ill J	i i i ImJ	¦ ' iliiiJ	¦ ¦ ¦ ln'J	i ¦ i 11 'ill	I ¦ i I .ml	' i ilmJ	¦ ' ¦ ImJ	¦ i ¦ I i»J	i ¦ i liml	I i il'»ii	¦ i I liml	» i ¦ I mJ

10-14 io-12 10-10 10-8 10"6 10"4 1 0 2 1

Concentration (|jg/m3)

Figure 2-7. Distributions of 2019 AirToxScreen Modeled Data for All Sources, Secondary
Production Sources, Point Sources, and Biogenic Sources for the Contiguous United States

2.4.2.3 Human Exposure Model (HEM)

EPA used the Human Exposure Model (HEM 4.2) to estimate formaldehyde concentrations on a site-
specific basis at multiple distances from releasing facilities. HEM 4.2 has two components: (1) an
atmospheric dispersion model, AERMOD, with included regional meteorological data; and (2) U.S.
Census Bureau population data at the Census block level. The current HEM version utilizes 2020
Census data—including all 50 states, the District of Columbia, Puerto Rico, and the U.S. Virgin Islands.
AERMOD estimates the magnitude and distribution of chemicals concentrations in ambient air in the
vicinity of each releasing facility within a user-defined radial distances out to 50 km (about 30 miles).
HEM also provides chemical concentrations in ambient air at the centroid of over 8 million census
blocks across the United States. This higher tier model was selected to expand on the IIOAC results by
providing more granularity in modeling individual facilities and more discrete distances, geospatial data
associated with modeling results for mapping and further analysis, and population data associated with
modeled results.

Ambient air concentrations at the census block level were modeled by HEM and are shown in Figure
2-8. These aggregated concentrations are the summed stack and fugitive modeled concentrations, which
can include the summation of multiple adjacent facilities, at specific locations. The site-specific
concentration results represent the expected annual average ambient air concentration attributable from
all modeled TRI releases of TSCA COUs, in some census blocks accounting for concentrations from

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multiple releasing facilities. Concentrations ranged from 0 to 8.9 |ig/m3. Census blocks with modeled
total concentrations below the 95th percentile biogenic formaldehyde threshold of 0.28 |ig/m3 are
presented in grey. Turquoise dots show census blocks with concentrations ranging from 1 to 5 times the
biogenic threshold, purple dots show concentrations from 5 to 10 times the biogenic threshold, and pink
dots show values greater than 10 times the biogenic threshold. Across the country, a total population of
105,463 people (based on 2020 Census data) live in census blocks shown with ambient air.

Elevated ambient air concentrations of formaldehyde from industrial releases appear most densely
concentrated in the southeastern United States. Census blocks with elevated concentrations are found
throughout the country, with some regions showing fewer overall TRI facilities, and fewer releases
resulting in elevated air concentrations.

Patterns in the relative contribution of stack and fugitive releases, and the distribution of results at
varying radial distances from the releasing facility were examined (Figure 2-9). Each vertical bar and
median line indicate the shape of the distribution of concentrations by release type for individual
facilities. These results indicate that concentrations resulting from fugitive emissions are greater than
those from stack emissions closer to the releasing facility, but concentrations from stack emissions tend
to become greater at further distances. As many facilities report only a single release type (either
fugitive or stack), the total concentration distributions represent a greater number of facilities than the
corresponding fugitive and stack distributions and tend to fall somewhere between the fugitive and stack
values. Total modeled concentrations tend to reach their maximum within 1,000 m of a facility. Values
represented in this analysis are directly modeled at the 16 radial points around each distance ring, rather
than census block centroids, and can therefore be located much closer to the releasing facility and
represent much higher concentrations. These points are not associated with population estimates, and in
some cases the modeled distances may still be within a facility property boundary.

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1568

1569	Figure 2-8. Map of Contiguous United States with HEM Model Results for TRI Releases Aggregated and Summarized by Census

1570	Block

1571	Census blocks with modeled total concentrations below the 95th percentile biogenic formaldehyde threshold of 0.28 (ig/m3 are presented in

1572	grey. Turquoise dots show census blocks with concentrations ranging from 1 to 5 times the biogenic threshold, purple dots show

1573	concentrations from 5 to 10 times the biogenic threshold, and pink dots show values greater than 10 times the biogenic threshold.

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£ 101

O)

•2 10u
2

c

0

g 10 1

O

o

-in_2-s—

-Q

E

< 10 •

<1)

O 10"'

Release Type and Metric

| Fugitive Median

Fugitive Max

| Stack Median

Stack Max

| Total Median

Total Max

1,000	2,500	5,000

Distance (m)

10,000	15,000	25,000	50,000

Figure 2-9. Median and Maximum Concentrations (Fugitive, Stack, and Total Emissions) across
the 11 Discrete Distance Rings Modeled in HEM

2A3 Integrating Various Sources of Formaldehyde Data	

Monitoring data from AMTIC, modeled exposures calculated from IIOAC, and modeled data from
AirToxScreen were compiled to understand how exposures from COUs fit into the broader context of
available information on formaldehyde. Figure 2-10 shows the distributions of data from these datasets.
As shown these distributions overlap. At the national scale, populations are exposed to many different
sources of formaldehyde (COUs, secondary, biogenic, etc./ Modeled exposure estimates downwind
from TSCA COU releases are variable across COUs and locations. In some locations the concentrations
from COUs dominate total concentrations of formaldehyde in ambient air. In most of the country
however, ambient air concentrations are dominated by other sources (secondary, biogenic, etc.)
according to AirToxScreen. All populations are exposed to concentrations between the various sources
of formaldehyde.

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AMTIC (Monitoring)
(N= 199.466)

IIOAC (Modeled)
(N=35)

AirTox Total Sources (Modeled)
(N=76.726)

ro AirTox Point Sources (Modeled)
O	(N=76,364)

AirTox Biogenic Sources (Modeled)
(N=76.726)

AirTox SecondarySources (Modeled)
(N=76.726)

Legend

25* Percentile 75* Percentile

Median 1.5*IQR

IQR

%



+



¦O,

Concentration (pg/m3)

'C/O

Data Source

AMTIC (Monitoring) • AirTox (Modeled) • IIOAC (Modeled)

'o

'Oo

Figure 2-10. Distributions of AMTIC Monitoring Data, IIOAC Modeled Data, and AirToxScreen
Modeled Data

EPA recognizes that the different model estimates are not directly comparable. For example, the IIOAC
results represent a 95th percentile annual average concentration between 100 to 1,000 m from the release
point. In contrast, AirToxScreen concentrations represent annual average concentrations at the census
tract scale. Given the spatial scale difference it is expected that AirToxScreen results could
underestimate concentrations on a smaller scale (i.e.. near facilities) or have lower concentration
estimates than IIOAC and this difference can be seen in Figure 2-10. Additionally, only point source
data within AirToxScreen may represent a broader set of formaldehyde releases that include releases
associated with TSCA COUs.

Furthermore, the AMTIC data represent a range of samples collected at various locations (independent
of TSCA releases of formaldehyde) and collection durations are much shorter than a year (5 minutes to
24 hours). Despite these uncertainties, these data suggest that formaldehyde concentrations from TSCA
sources are higher than formaldehyde concentrations that are expected to occur due to natural formation.
These higher concentrations will be driven by the location of release. These COUs are listed in Section
2.4.2.1 and this conclusion is further supported by the FIEM analysis.

2.5 Weight of Scientific Evidence and Overall Confidence in Exposure

Assessment

As described in the 2021 Draft Systematic Review Protocol (J.S. EPA, 2021b). the weight of scientific
evidence supporting exposure assessments is evaluated based on the availability and strength of
exposure scenarios and exposure factors, measured and monitored data, estimation methodology and
model input data, and, if appropriate, compari sons of estimated and measured exposures. The strength of

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each of these evidence streams can be ranked as either robust, moderate, slight, or indeterminate. For
each component of this exposure assessment, EPA evaluated the weight of scientific evidence for
individual evidence streams and then used that information to evaluate the overall weight of evidence
supporting each set of exposure estimates. General considerations for evaluating the strength of evidence
for each evidence stream are summarized in Table 7-6 of the Draft Systematic Review Protocol
Supporting TSCA Risk Evaluations for Chemical Substances (	). Specific examples of

how these considerations can be applied to overall weight of scientific evidence conclusions are
provided in Table 7-7 of the Draft Systematic Review Protocol (	)21b). The weight of

scientific evidence supporting each element of the human health exposure assessment are discussed in
the occupational exposure assessment (	)24k) consumer exposure assessment (

2024d). indoor air assessment ( v << \ ,^24i) and ambient air assessment (U.S. EPA. 2024a)
modules.

Overall confidence descriptions of high, medium, or low are assigned to the exposure assessment based
on the strength of the underlying scientific evidence. When the assessment is supported by robust
evidence, overall confidence in the exposure assessment is high; when supported by moderate evidence,
overall confidence is medium; when supported by slight evidence, overall confidence is low.

OPPT will seek input on its use of inputs and assumptions in the exposure assessments for occupational,
consumer, outdoor air, and indoor air scenarios, in part to understand whether its approach may
compound one conservative assumption upon another in a manner that leads to unrealistic or un-
addressable outcomes.

2,5,1 Overall Confidence in Occupational Exposure Assessment	

The confidence in the occupational exposure assessment varies from low to high, the confidence is
based on the strengths, limitations, and uncertainties associated with the exposure estimates for each
individual occupational exposure scenario. Most COUs have medium confidence based on moderate to
robust and moderate weight of scientific evidence conclusions. The primary strength of most of the
inhalation assessments is that it uses monitoring data that is chemical-specific and is directly applicable
to the exposure scenario. The use of applicable monitoring data is preferable to other assessment
approaches such as modeling or the use of occupational exposure limits. The principal limitation of the
monitoring data is the uncertainty in the representativeness of the data due to some scenarios having
limited exposure monitoring data in the literature or the available monitoring data lacking additional
contextual information. Additionally, different sampling objectives may introduce uncertainty since
OSHA and other studies may target workers with the highest expected exposures. For many of the
COUs, the EPA received aggregated data from industry; therefore, EPA was unable to distinguish each
site's contribution to the exposure estimates. EPA also assumed 8 exposure hours per day and 250
exposure days per year based on continuous formaldehyde exposure for each working day for a typical
worker schedule. It is uncertain whether this captures actual worker schedules and exposures.

Some of the COUs lacked monitoring data; therefore, EPA used models to estimate inhalation
exposures. EPA addressed variability in inhalation models by identifying key model parameters to apply
a statistical distribution that mathematically defines the parameter's variability. EPA defined statistical
distributions for parameters using documented statistical variations where available. Where the
statistical variation was unknown, assumptions were made to estimate the parameter distribution using
available literature data, such as General Scenario (GS) and Emission Scenario Document (ESDs).
However, there is uncertainty as to the representativeness of the parameter distributions with respect to
the modeled scenario because the data are often not specific to sites that use formaldehyde. In general,
the effects of these uncertainties on the exposure estimates are unknown, as the uncertainties may result

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in either overestimation or underestimation of exposures depending on the actual distributions of each of
the model input parameters.

As described in the Draft Occupational Exposure Assessment for Formaldehyde (	24k).

EPA has low confidence in the inhalation estimates for the four COUs below based on a slight weight of
scientific evidence:

•	Industrial use - non-incorporative activities - process aid in: oil and gas drilling, extraction, and
support activities; process aid specific to petroleum production, hydraulic fracturing

•	Commercial use - chemical substances in treatment/care products - laundry products and
dishwashing products

•	Commercial use - chemical substances in outdoor use products - explosives materials

•	Commercial use- chemical substances in packaging, paper, plastic, hobby products - paper
products; plastic and rubber products; toys, playground, and sporting equipment

This was mainly due to the low number of monitoring samples available, lack of information specific to
formaldehyde usage for the given COUS and uncertainties with the representativeness of the monitoring
data. However, EPA concluded that the underlying data still provides a plausible estimate of exposures
for these OESs.

EPA had moderate weight of scientific evidence conclusions for all dermal scenarios assessed. The
primary strength of the dermal assessment is that most of the data that EPA used to inform the modeling
parameter distributions have overall data quality determinations of either high or medium from EPA's
systematic review process, such as the 2020 CDR (	1020b). A limitation of the assessment is

that some COUs lacked formaldehyde weight concentration data.

2.5.2 Overall Confidence in the Consumer Exposure Assessment

EPA has medium confidence in the inhalation exposure assessment for consumers. As detailed in
Section 3.2 of the Draft Consumer Exposure Assessment for Formaldehyde (U.S. EPA. 2024d). the
inhalation exposure assessment is supported by a robust monitoring dataset and robust modeling
approaches.

Aside from the potential exposures to water treatment, laundry and dish washing, and lawn and garden
products, EPA has medium confidence in the consumer inhalation modeling approaches and model input
data—including TSCA COU-specific product weight fractions identified from SDS of consumer
products currently on the market, the quality and applicability of the CEM for the assessment of realistic
consumer exposure scenarios that are representative of COUs, common consumer use patterns (e.g.,
TSCA COU-specific amount used, duration and frequency of use (	)) according to the

EPA Exposure Factors Handbook (1 c< « i1 \ JO I I) and the 1987 Westat survey (Westat. 1987) and
applicable to most population groups. EPA also has medium confidence in the quality and
representativeness of air monitoring data. This use of TSCA COU-specific monitoring information
increases confidence in estimated inhalation exposures.

EPA has medium confidence in the dermal exposure assessment for consumers. As detailed in Section
3.2 of the Draft Consumer Exposure Assessment for Formaldehyde (U.S. EPA. 2024d). EPA has
medium confidence in the Thin Film Model, which EPA used to estimate dermal loading from spray and
liquid consumer products, and in default model input values used in the dermal exposure assessment of
realistic consumer exposure scenarios, which are representative of COUs, common consumer use
patterns, and applicable to most population groups. EPA has high confidence in the TSCA COU-specific
product weight fractions identified from SDSs of consumer products currently on the market and

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medium confidence in the applied quantity remaining on skin (Qu) constant. Although a On of 10.3
mg/cm2 (used to approximate hand immersion and wiping experiments using oil-based products (

)) is assumed to be realistic and protective of most liquid product consumer dermal exposures
to formaldehyde, it is conceivable that a lower Qu may be applicable for some consumer exposure
scenarios (e.g., consumer uses liquid product with personal protective equipment [PPE] that prevents
immersion or development of thin film of formaldehyde on the skin). No monitoring data are available
on dermal exposures for consumers.

2.5.3	Overall Confidence in the Indoor Air Exposure Assessment

EPA has medium confidence in the overall findings for the indoor air exposure assessment. As detailed
in Section 3.2.1 of the Draft Indoor Air Exposure Assessment for Formaldehyde (	24|), the

exposure assessment is supported by a robust monitoring dataset and robust modeling approaches. EPA
has medium confidence that the exposure scenarios evaluated in this assessment are reasonable and
representative of people who spend most time indoors. The indoor air exposure scenario assumes
continuous exposure to indoor air over a lifetime.

EPA has medium confidence in the quality and representativeness of indoor air monitoring data. The set
of 16 studies used as an indication of indoor air concentrations and as a basis for comparison to modeled
concentrations were rated high quality. This dataset includes the American Healthy Homes Survey II, a
quality nationally representative formaldehyde residential indoor air monitoring study administered by
EPA and the U.S. Department of Housing and Urban Development (HUD). EPA also has medium
confidence in the indoor air modeling approaches and model input data, including the quality and
applicability of the Consumer Exposure Model and the emission rates and fluxes from quality product
emission studies used to refine the model. The set of nine studies incorporated into indoor air modeling
were, altogether, rated medium quality.

EPA considered concordance between monitored and modeled concentrations. Monitored concentrations
are expected to reflect aggregate concentrations resulting from multiple sources of formaldehyde and are
therefore not directly comparable to modeled concentrations estimated for specific sources. In addition,
CEM does not incorporate chemical half-life. Therefore, it is unclear whether the modeling results are
reflective of most indoor air home environments in American residences. However, the fact that
modeled concentrations are within the same order of magnitude of monitored concentrations increases
confidence in modeled concentrations. The availability of both modeled concentrations and monitoring
data provides information about both the aggregate exposures from all sources contributing to indoor air
concentrations as well as information about the relative contributions of individual TSCA COUs.

Based on consideration of the weight of scientific evidence, EPA has medium confidence in the overall
findings for the indoor air exposure assessment (II	2024D due to a high confidence in the CEM

used and emission fluxes and rates from quality product emission studies used to refine the model, in
comparison with American Healthy Homes Survey II.

2.5.4	Overall Confidence in the Ambient Air Exposure Assessment

EPA has high confidence in the overall characterization of exposures for the ambient air exposure
assessment. As described in the Draft Ambient Air Exposure Assessment for Formaldehyde (U.S. EPA.
2024a). exposure estimates rely upon direct reported releases and peer-reviewed models to derive
exposure concentrations at distances from releasing facilities where individuals within the general
population reside for many years. Furthermore, ambient monitoring data supports the presence of
formaldehyde in the ambient air and shows comparable monitored values to EPA's modeled
concentrations.

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For industrial TSCA COUs, EPA has a moderate to robust weight of scientific evidence as the databases
have high data quality scores and are supported by numerous data points. A primary strength of TRI and
NEI data is that these programs compile the best readily available release data for large facilities.
Limitations are that these programs may not cover some sites that emit formaldehyde as both programs
have conditions that must be met prior to being required to report releases. For formaldehyde, the
potential contribution of combustion sources is an uncertainty and use of the full facility data complicate
singular TSCA COU estimates, such that emissions at one site may include multiple sources under
multiple COUs that include combustion sources and non-combustion sources.

In general, for commercial COUs, EPA has a moderate weight of scientific evidence as TRI and NEI
have high data quality and generic scenarios that have a medium to high data quality rating. EPA relied
upon professional judgement in mapping TRI and NEI industrial sectors to commercial COUs. There is
some uncertainty that a commercial TSCA COU may occur across several industrial sectors beyond the
industrial sector used for analysis. In addition, some industrial sectors cover both industrial and
commercial operations, so they may overestimate air releases occurring in a commercial setting. Four
commercial COUs either lacked sufficient data or was supported by a slight weight of evidence:

•	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.

EPA estimated the exposed population to modeled releases to ambient air; however, these estimates are
considered an underestimate of total exposed population. EPA limited this modeling to the 810 TRI
facilities directly reporting with Form R. As indicated in the TRI reporting, the ambient air releases
reported to EPA are from different estimation approaches (e.g., emission factors) and may not be from
active stack monitoring. These TRI emissions are a subset of the approximately 49,000 distinct facilities
with estimated emissions in NEI but are of greater confidence due to the direct reporting rather than the
indirect, state-specific reporting currently used to develop the NEI. Finally, the exposed population
estimates from HEM are derived by averaging the modeled annual concentration at the proximate census
block centroids across the census block, using site-specific meteorological conditions. EPA did not
make facility-specific adjustments to modeling receptor files based on land use analysis to capture the
highest proximate populations in this analysis, therefore population estimates are biased against
capturing the populations of the most highly exposed residents within rural (and therefore larger) census
blocks. Therefore, while EPA has a high confidence in the methods used, based on the expected
underestimation of the exposed population estimates, the confidence is medium.

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3 HUMAN HEALTH HAZARD SUMMARY

EPA's OPP and OPPT collaborated to develop a joint hazard assessment for formaldehyde (

20244). This joint assessment evaluated available human health hazard and dose-response information
for formaldehyde and identified hazard values to support risk assessments in both offices.

For cancer and non-cancer hazards associated with chronic inhalation exposures, the joint hazard
assessment relies upon the analysis already completed in the draft IRIS assessment on formaldehyde
inhalation (U.S. EPA. 2022b) and peer reviewed by the National Academies of Sciences, Engineering,
and Medicine (NASEM) (NASEM. 2023). The systematic review literature searches, data quality
review, evidence integration, dose-response analyses, and peer review performed in support of the IRIS
assessment reflect the best available science on formaldehyde hazards from chronic inhalation exposures
and are consistent with the needs of both OPP and OPPT.

To identify additional available hazard and dose-response information for acute inhalation, dermal, and
oral formaldehyde exposures, EPA used a fit-for-purpose systematic review protocol, integrating the
needs and approaches of both OPP and OPPT. Details of the fit-for-purpose systematic review protocol
used in OPPT's work on this assessment are described in the Systematic Review Protocol for the Draft
Risk Evaluation for Formaldehyde (U.S. EPA. 2023 a). This approach is based in part on the OPPT
systematic review approach described in the Draft Systematic Review Protocol Supporting TSCA Risk
Evaluations for Chemical Substances (	)21b).

EPA identified a range of factors that may increase susceptibility to formaldehyde and considered
susceptibility throughout the hazard assessment. Descriptions of how EPA incorporated PESS due to
greater biological susceptibility into the risk evaluation are provided in Appendix C. Factors that may
increase susceptibility to formaldehyde exposures include chronic respiratory disease, lifestage, sex, and
co-exposure to chemical and non-chemical stressors that influence the same health outcomes.

3.1 Summary of Hazard Values

The non-cancer and cancer hazard values identified for inhalation, dermal, and oral exposures to
formaldehyde in the joint hazard assessment (	24i) are summarized in Table 3-1.

Consistent with the recommendations of the Human Studies Review Board (HSRB), OPPT will seek
input on its hazard assessment, particularly with regards to the PODs and uncertainty/extrapolation
factors for acute and chronic non-cancer assessment and the extent to which the draft hazard assessment
for formaldehyde appropriately considered recommendations from other federal advisory committees
(e.g., NASEM, HSRB).

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1826 Table 3-1. Hazard Values Identified for Formaldehyde		

Exposure
Scenario

Hazard Value

Uncertainty
Factors

T otal
Uncertainty
Factor

Study and Toxicological Effects

Inhalation
Acute
(15-minute
duration)

NOAEC and BMCL =
0.5 ppm

(0.62 mg/m3) as a 15-
minute peak exposure

UFh= 10

Total UF= 10

Kulle et al. (1987); supported bv:

LOAEC = 1 ppm (mg/m3) based on eye irritation in adult volunteers
Mueller et al. (2013)

LOAEC = 0.3 ppm over 4 hours, with 15-minute peaks of 0.6 ppm, based on eye
irritation in hypersensitive adult volunteers
Lang et al. (2008)

LOAEC= 0.5 ppm over 4 hours, with peaks of 1 ppm (0.62/1.23 mg/m3), based
on eye irritation in adult volunteers

Inhalation
Chronic non-
cancer3

(Long-term, >6
months)

BMCLio = 0.017 ppm
(0.021 mg/m3)

UFh = 3

Total UF = 3

POD is derived from the IRIS RfC (U.S. EPA. 2022bV The specific BMCLm
value used here is based on reduced pulmonary function in children in
Krzyzanowski et al. (1990). but is consistent with the RfC. derived based on.
pulmonary function, allergy-related conditions, asthma (prevalence and degree of
asthma control) in people, as reported in Annesi-Maesano et al. (2012).
Matsunaga et al. (2008). Venn et al. (2003). and Krzyzanowski et al. (1990).

Inhalation

Chronic

Cancer

Adult-based IUR:
0.0079 ppm1
(6.4 x 10"6 (ng/m3)-1)

ADAF-adjusted IUR:

0.013 ppm1

(1.1 x 10~5 (ng/m3)-1)

N/A

N/A

IUR established bv IRIS (U.S. EPA. 2022b) based on data on nasopharyngeal
cancer in people reported in Beane-Freeman et al. (2013).

Dermal
Acute

Induction:
EC3 = 0.4% (100
|ig/cm2) in 4:1
acetone:olive oil

UFA= 10
UFh = 10

Total UF= 100

Basketter et al.. (2003)

based on induction of dermal sensitization in mice

Elicitation:
BMDLio= 10.5
Hg/cm2 (0.035%)

UFh = 10

Total UF= 10

Flyvholm et al., (1997)

based on threshold for elicitation of dermal sensitization in people

Oral

Short-Term/
subchronic
(1-30 days),

HED= 6 mg/kg-day

UFa = 3
UFh = 10

Total UF = 30

Til (1988)

NOAEL= 25 mg/g-day; LOAEL =125 mg/kg-day based on gastrointestinal
histopathology in rats

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Exposure
Scenario

Hazard Value

Uncertainty
Factors

T otal
Uncertainty
Factor

Study and Toxicological Effects

Oral
Chronic

HED = 3.6 mg/kg-day

UFa = 3
UFH= 10

Total UF = 30

Civo Inst.(1987); Til (1989)

NOAEL= 15 mg/g-day; LOAEL = 82 mg/kg-day based on gastrointestinal
histopathology in rats

" This value is used to estimate risks from both sub-chronic and chronic occupational exposures.

Point of departure (POD) = A data point or an estimated point that is derived from observed dose-response data and used to mark the beginning of extrapolation to
determine risk associated with lower environmentally relevant human exposures; NOAEL = no-observed adverse-effect level; LOAEL = lowest-observed adverse-
effect level; UF = uncertainty factor; UFA = extrapolation from animal to human (interspecies); UFH = potential variation in sensitivity among members of the
human population (intraspecies). UFL = use of a LOAEL to extrapolate a NOAEL. UFS = use of a short-term study for long-term risk assessment. UFDb = to account
for the absence of key data (i.e., lack of a critical study). IUR= inhalation unit risk; ADAF-adjusted IUR = IUR for calculating cancer risks associated with a full
lifetime of exposure

1827

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3.2 Weight of Scientific Evidence and Overall Confidence in Hazard
Assessment

As described in the Draft Systematic Review Protocol Supporting TSCA Risk Evaluations for Chemical
Substances (U.S. EPA. 2021b). the weight of scientific evidence supporting hazard assessment and dose
response is evaluated based on the quality of the key studies, consistency of effects across studies, the
relevance of effects for human health, confidence in the dose-response models, and the coherence and
biological plausibility of the effects observed. The weight of evidence and overall confidence in chronic
inhalation hazard values derived by IRIS are described in the draft IRIS assessment (	22b).

The weight of evidence and sources of confidence and uncertainty in dermal, oral, and acute inhalation
hazard values derived by OCSPP are described in the hazard assessment (	2024i). This section

summarizes overall confidence and sources of uncertainty in the hazard values used to develop risk
estimates in this risk characterization.

3.2.1	Overall Confidence in the Acute Inhalation POD

Overall confidence in the acute inhalation POD is medium. As described in the joint hazard assessment
(I	ii), the acute POD is based on a robust dataset of evidence for sensory irritation in

humans, including several high-quality controlled exposure studies with relevance for acute exposure
scenarios. Concordance of reported sensory irritation effects and the effect levels reported across acute
exposure studies increases confidence in the final POD. Variability across individuals' response
contributes to uncertainty around effect levels that are protective across the population. A lOx
uncertainty factor is applied to account for uncertainty related to intraindividual variability.

This acute POD focuses on defining peak threshold exposure concentrations rather than average 8- or
24-hour exposure concentrations. There is some uncertainty around the degree to which duration
influences effect levels because there are no studies available that provide direct evidence that effect
levels following 8- or 24-hour exposures are the same as effects following 2 to 5 hours of exposure.

Immune-mediated respiratory effects like asthma may also have relevance for acute hazard, but
available studies do not provide sufficient information to characterize dose-response relationships for
acute inhalation exposures. Although this may be a source of uncertainty for the acute POD, dose-
response data for these additional respiratory endpoints are used as the basis for the chronic inhalation
POD.

3.2.2	Overall Confidence in the Chronic, Non-cancer Inhalation POD

As described in the draft IRIS assessment (	322b). overall confidence in the chronic non-

cancer inhalation POD is high. The chronic POD derived by IRIS is supported by a robust database of
evidence for a range of endpoints in humans and animals. The overall POD is informed by dose-
response information in humans across multiple respiratory endpoints and reflects concordance in effect
levels identified across those endpoints. EPA also considered dose-response information for
reproductive and developmental effects in selection of the overall POD. While there is more uncertainty
around the PODs derived for these endpoints, the overall POD is expected to be protective of these
reproductive and developmental effects in humans. Many of the observational epidemiology studies
providing the quantitative basis for the chronic POD reflect relevant human exposure scenarios in homes
and schools. In addition, several of the studies include children with asthma or other sensitive groups.

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3.2.3	Overall Confidence in the Chronic IUR

As described in the draft IRIS assessment (U.S. EPA. 2022b). overall confidence in the preferred unit
risk estimate is medium. The IUR derived for nasopharyngeal cancer is informed by a robust dataset of
both human and animal data. The availability of human data eliminates the need to extrapolate from
animal studies, increasing the confidence in the IUR. In addition, the IUR derived from animal data is
similar to the IUR derived from human evidence, further increasing confidence in the IUR. Sources of
uncertainty in the IUR include reliance on extrapolation from high doses that occur in occupational
settings to lower doses that may occur in the general population, reliance on data from a single high
quality occupational cohort study that may not capture the sensitivity of susceptible populations or
lifestages, and reliance on mortality data as a surrogate for cancer incidence.

EPA was not able to derive IURs for all tumor sites associated with formaldehyde exposure. This is a
source of uncertainty and may lead to an underestimate of risk. Although EPA was able to derive an
IUR for myeloid leukemia, the lack of confidence in the dose-response data and IUR for myeloid
leukemia is a source of uncertainty. The cancer risk estimates presented in this risk characterization do
not include risks for myeloid leukemia and other tumor sites. Based on the IUR estimated for myeloid
leukemia in the draft IRIS document, IRIS estimated that consideration of myeloid leukemia may
increase the age-dependent adjustment factor (ADAF)-adjusted IUR by as much as four-fold.

3.2.4	Overall Confidence in the Dermal POD

Overall confidence in the dermal POD is medium. As described in the OCSPP joint hazard assessment
(t; S 1 P \ 20241). the dermal POD is derived from an extensive dataset on dermal sensitization in
human, animal, and in vitro studies. Multiple streams of evidence from studies evaluating elicitation
thresholds in sensitive people and induction thresholds in animal and in in vitro assays arrive at similar
effect levels. While there are some uncertainties associated with the human studies related to lack of
clarity in methods and data reporting, concordance in effect levels across multiple streams of evidence
increases confidence in the POD. The potential impact of methanol present in available dermal
formaldehyde studies is a source of uncertainty in the POD. While there is substantial variation in
sensitization responses across individuals, application of a 10x uncertainty factor is used to account for
uncertainty related to intraindividual variability.

3.2.5	Overall Confidence in the Subchronic and Chronic Oral POPs	

Overall confidence in the subchronic and chronic oral PODs is medium. As described in the OSCPP
joint hazard assessment (	0241). the subchronic and chronic oral PODs rely on a limited

database of animal studies but are supported by three studies that report consistent patterns of
gastrointestinal damage at similar dose levels.

Due to technical challenges around generating pure and stable formaldehyde treatments for oral
exposure, most of the available animal studies have major limitations and uncertainties. Among the
available studies that are not confounded by the presence of methanol, gastrointestinal effects are the
most sensitive endpoint evaluated. Reduced drinking water intake in the high dose groups reduced
confidence in each of the chronic studies when considered in isolation. However, when considered in
conjunction with the results of the 28-day study that included water-restricted controls, EPA has
confidence that the reported effects are attributable to formaldehyde exposure.

There is very limited information on reproductive, developmental, and immune endpoints following oral
exposure to formaldehyde. Although there are some studies that suggest effect levels for these endpoints
may be more sensitive than those used as the basis for the POD, the only studies that evaluate
reproductive, developmental, and immune endpoints are confounded by the presence of methanol.

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1918	Evidence of reproductive and developmental effects reported in humans and animals following

1919	inhalation exposure to formaldehyde indicates that such effects are possible following formaldehyde

1920	exposure. Similarly, the available data do not evaluate factors that may increase susceptibility to oral

1921	formaldehyde exposure in sensitive groups or lifestages. The lack of data on these endpoints and

1922	sensitive groups and lifestages following oral exposure could be perceived as uncertainty; however, the

1923	likelihood of a lower POD being identified based on these outcomes is low given the effect used as the

1924	basis of the current PODs (gastrointestinal effects) are close to the portal of entry, first pass metabolism

1925	via the oral route, and the reactivity of formaldehyde.

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4 HUMAN HEALTH RISK CHARACTERIZATION

4.1 Risk Characterization Approach

The exposure scenarios, populations of interest, and toxicological endpoints used for evaluating risks
from acute and chronic exposures are summarized below in Table 4-1. EPA estimated cancer and non-
cancer risks from occupational, consumer, and general population exposures as described below.

While EPA will consider the standard risk benchmarks shown in Table 4-1 associated with interpreting
margins of exposure and cancer risks, EPA cannot solely rely on those risk values. Risk estimates
include inherent uncertainties and the overall confidence in specific risk estimates varies. The analysis
provides support for the Agency to make a determination about whether formaldehyde poses an
unreasonable risk to human health and to identify drivers of unreasonable risk among exposures for
people (1) with occupational exposure to formaldehyde, (2) with consumer exposure to formaldehyde,
(3) with exposure to formaldehyde in indoor air, and (4) who live or work in proximity to locations
where formaldehyde is released to air. Concurrent with this draft TSCA Risk Evaluation, EPA is
releasing a preliminary risk determination for formaldehyde.

The Agency also will consider naturally occurring sources of formaldehyde (i.e., biogenic, combustion,
and secondary formation) and associated risk levels from, and consider contributions from all sources as
part of a pragmatic and holistic evaluation of formaldehyde hazard and exposure in making its
unreasonable risk determination. If an estimate of risk for a specific scenario exceeds the benchmarks,
then the decision of whether those risks are unreasonable is both case-by-case and context driven. In the
case of formaldehyde, EPA is taking the risk estimates of this draft human health risk assessment
(HHRA) in combination with a thoughtful consideration of other sources of formaldehyde, to interpret
the risk estimates in the context of an unreasonable risk determination.

Table 4-1. Use Scenarios, Populations of Interest, and Toxicological Endpoints Used for Acute and
Chronic Exposures	

Populations
of Interest
and

Exposure
Scenarios

Workers a

Acute - Adolescent (>16 vears old) and adult workers exposed to formaldehyde in a single
workday for 15 min or longer

Chronic - Adolescent (>16 vears old) and adult workers exposed to formaldehyde over a full-shift
workday for 250 days per year for 40 working years

Consumers and Bystanders

Acute - Consumers across all aae aroups (depending on the product or article) exposed to
formaldehyde result from product or article use. Exposures are estimated to be 15-minute peak
concentrations. It should be noted that the 15-minute peak concentration for a given TSCA COU
and exposure scenario may occur several hours after product use.

Chronic - Consumers across all aae aroups (dependina on the product or article) exposed to
formaldehyde result from product or article use up to 78 years.

General Population Indoor Ambient Air Exposure b

Chronic - People across all aae aroups exposed to formaldehyde throuah ambient air continuously
up to 78 years.

General Population Outdoor Ambient Air Exposure b

Chronic - People across all aae aroups exposed to formaldehyde throuah ambient air near
industrial release site continuously up to 78 years.

Health

Effects,

Hazard

Non-cancer Acute Hazard Values

Acute inhalation health effect: sensory irritation

• Acute inhalation POD (15-minute duration) = 0.5 ppm (0.62 mg/m3)

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Values and
Benchmarks

•	Uncertainty Factors (Benchmark MOE) = 10 (UFa = 1; UFh = 10; UFl = 1; UFs=l;
UFd=1)

Acute dermal health effect: sensitization (elicitation)

•	Acute POD = 10.5 |gg/cm2

•	Uncertainty factors (Benchmark MOE) = 10 (UFa = 1; UFh = 10; UFl = 1; UFs=l;
UFd=1)

Acute oral health effect: no acute oral PODs identified
Non-cancer Subchronic Hazard Values

Subchronic oral health effects: Gastrointestinal effects

•	Oral HED = 6 mg/kg-day

•	Uncertainty Factors (Benchmark MOE) = 30 (UFa = 3; UFh = 10; UFl = 1; UFs=l;
UFd=1)

Non-cancer Chronic Hazard Values

Chronic inhalation health effects: Respiratory effects, including reduced pulmonary function,
allergy-related conditions, asthma (prevalence and degree of asthma control), and sensory
irritation

•	Inhalation HEC = 0.017 ppm (0.021 mg/m3)

•	Uncertainty Factors (Benchmark MOE) = 3 (UFa = 1; UFh = 3; UFl = 1; UFs = 1; UFd =

1)

Chronic oral health effects: Gastrointestinal effects

•	Oral HED = 3.6 mg/kg-day

•	Uncertainty Factors (Benchmark MOE) = 30 (UFa = 3; UFh = 10; UFl = 1; UFs = 1; UFd

= 1)

Cancer Hazard Values

Inhalation cancer hazard for formaldehyde is based on nasopharyngeal cancers

•	IUR = 0.0079 ppm-1 (6.4* 10"6 (jig/m3)-1)

•	ADAF applied for early life exposures

Oral and dermal cancer hazards are not quantified because there is insufficient data to support
derivation of cancer slope factors for these routes of exposure.	

" Adult workers (>16 years old) include both female and male workers.

b Inhalation exposures are described in terms of air concentrations and do not include lifestage-specific adjustments; risk
estimates based on air concentrations are intended to address risks to all lifestages.

MOE = margin of exposure; UFA = Interspecies uncertainty factor for animal-to-human extrapolation; UFH = Intraspecies
uncertainty factor for human variability; UFL = LOAEC-to-NOAEC uncertainty factor for reliance on a LOAEC as the POD

4.1.1 Estimation of Non-cancer Risks

EPA used a margin of exposure (MOE) approach to identify potential non-cancer risks. The MOE is the
ratio of the non-cancer POD divided by a human exposure dose. Acute and chronic MOEs for non-
cancer inhalation and dermal risks were calculated using Equation 4-1:

Equation 4-1.

MOE,

acute or chronic ~

Non — cancer Hazard value (POD)
Human Exposure

Where:

MOE

Hazard value (POD)
Human Exposure

Margin of exposure (unitless)
HEC (ppm) or HED (mg/kg-d)
Exposure estimate (in ppm or mg/kg-d)

MOE risk estimates may be interpreted in relation to benchmark MOEs. Benchmark MOEs are typically
the total UF for each non-cancer POD. If the numerical value of the MOE is less than the benchmark

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MOE, this relationship is a starting point to determine if there are unreasonable non-cancer risks. On the
other hand, if the MOE estimate is equal to or exceeds the benchmark MOE, risk is not indicated.
Typically, the larger the MOE, the more unlikely it is that a non-cancer adverse effect occurs relative to
the benchmark. When determining whether a chemical substance presents unreasonable risk to human
health or the environment, calculated risk estimates are not "bright-line" indicators of unreasonable risk,
and EPA has discretion to consider other risk-related factors apart from risks identified in risk
characterization.

4.1,2 Estimation of Cancer Risks

Extra cancer risks for repeated inhalations exposures to formaldehyde were estimated using Equation
4-2:

Equation 4-2.

Inhalation Cancer Risk = Human Exposure x IUR

Where:

Risk	= Extra cancer risk (unitless)

Human exposure = Exposure estimate (LADC in ppm)
IUR	= Inhalation unit risk

EPA has concluded that "the evidence is sufficient to conclude that a mutagenic mode of action of
formaldehyde is operative in formaldehyde-induced nasopharyngeal carcinogenicity" (

2022b). To account for increased nasopharyngeal cancer risks from early life exposures to
formaldehyde, EPA applies an ADAF.

Estimates of extra cancer risks are interpreted as the incremental probability of an individual developing
cancer over a lifetime following exposure {i.e., incremental, or extra individual lifetime cancer risk).

4.2 Risk Estimates

4.2.1 Risk Estimates for Workers

EPA estimated cancer and non-cancer risks for workers exposed to formaldehyde based on the
occupational exposure estimates that were described in Section 2.1. For many TSCA COUs, EPA did
not identify inhalation exposure data for ONUs, and therefore evaluated chronic risks using the central
tendency estimates for workers. EPA did not identify information for potential peak exposures by ONUs
and therefore did not quantify acute inhalation risks for ONUs. Risks to ONUs are assumed to be equal
to or less than risks to workers who handle materials containing formaldehyde as part of their job.

These risk estimates are based on exposures to workers in the absence of PPE such as gloves or
respirators. Section 2.5.1 contains an overall discussion on strengths, limitations, assumptions, and key
sources of uncertainty for the occupational exposure assessment. Additionally, the Draft Occupational
Exposure Assessment for Formaldehyde (	24k) contains a comprehensive weight of

scientific evidence summaries, which presents an OES-by-OES discussion of the key factors that
contributed to each weight of scientific evidence conclusion.

4.2.1.1 Risk Estimates for Inhalation Exposures

EPA estimated acute, sub-chronic and chronic non-cancer and chronic cancer risks to workers and
ONUs from inhalation. Generally, EPA expects workers to be exposed at higher formaldehyde
concentrations comparative to other populations. Across occupational exposure scenarios for full-shift

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estimates, the central tendency of air concentrations estimates ranged from 7.5 to 499.3 |ig/m3 (0.006 to
0.40 ppm) and high-end of air concentrations estimates ranged from 7.5 to 17,353.3 |ig/m3 (0.006 to
13.9 ppm), which is generally higher than the modeled estimates of ambient air (up to 5.7 |ig/m3) and
measured indoor air concentrations (-40 |ig/m3 at the 95th percentile of concentrations measured in
AHHS II).

Risk estimates vary across OESs/COUs. As shown in Figure 4-1, acute non-cancer risk estimates for
worker inhalation exposure range from 2.58x 10 3 to 11.6 for both high-end and central tendency
exposures. For COUs with multiple OESs or estimation approaches, the estimate with the highest high-
end value was illustrated. For the formaldehyde risk assessment, acute occupational risks were estimated
using 15-minute monitoring data, which in most cases is expected to represent activities with the highest
exposure potential for the scenario. Acute risk estimates below indicate that exposure is greater than the
hazard POD identified for 15-minute peak exposures based on sensory irritation reported in controlled
human exposure studies in healthy adult volunteers. All TSCA COUs except one COU have acute risk
estimates below an MOE of 10, and 39 TSCA COUs have acute risk estimates below an MOE of 1.

EPA did not identify inhalation exposure data for peak exposures for the industrial use as process aid in:
Oil and gas drilling, extraction, and support activities; process aid specific to petroleum production,
hydraulic fracturing. Of note, the Commercial use - laundry and dishwashing products COU only had
one identified data point for peak exposures, and therefore one risk value is provided.

As shown in Figure 4-2, chronic non-cancer risk estimates for worker inhalation exposure range from
2.42x 10 3 to 6.4 for both high-end and central tendency exposures. For COUs with multiple OESs or
estimation approaches, the scenario with the highest central tendency value was illustrated. Chronic non-
cancer risk estimates below 1 indicate that exposure is greater than the hazard point of departure based
on respiratory effects in children. While some healthy adult workers may be less susceptible to
formaldehyde at those concentrations, MOEs below 1 may be a concern for susceptible workers such as
those with chronic respiratory disease or those with co-exposures that contribute to similar respiratory
effects. Of the 49 TSCA COUs evaluated, 48 TSCA COUs have chronic risk estimates below an MOE
of 3, and 47 TSCA COUs have chronic risk estimates below an MOE of 1. Sub-chronic, non-cancer risk
estimates follow a similar risk profile and are not separately illustrated.

Worker cancer risk estimates for inhalation exposure range from 4.05 x ] 0 6 to 1.3/10 2 for both high-
end and central tendency exposures, as shown in Figure 4-3. For COUs with multiple OESs or
estimation approaches, the scenario with the highest central tendency value was illustrated. The cancer
risk estimates calculated for workers do not include risks for myeloid leukemia and other tumor sites
because EPA was not able to quantify those risks with confidence. Cancer risk estimates may therefore
underestimate risks. Of the 49 TSCA COUs evaluated, 46 TSCA COUs have chronic risk estimates
greater than 1 in 10,000. All risk estimates including for all exposure scenarios evaluated are provided in
the "Supplemental file: Occupational Risk Calculator."

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3

o
o

Processing- Incorporation into an article- Additive in.

rubber...

Commercial Use- Chemical Substances in treatment products-.

Laundry,

Industrial Use- Non-incorporative activities-.

Oxidizing/reducing...

Manufacturing-Importing

Processing- Repackaging-Sales..-

Commercial Use- Chemical substances in agriculture use

products- Lawn...

Commercial Use- Chemical substances in outdoor use products-.

Explosive...

Industrial Use- Non-incorporative activities- Used in:

construction

Distribution- Distribution in Commerce -

Commercial Use- Chemical substances in packaging, paper,.

plastic, hobby products-Ink, toner...

Processing- Incorporation into an article- Adhesives...

Processing- Recycling

Processing of Formaldehyde into Formulations, Mixtures (15)...

Industrial Use- Non-incorporative activities- Process aid.

in: Oil and gas...

Commercial Use-Chemical substances in packaging,
paper...-Paper products...

Commercial Use- Chemical Substances in construction...-

Adhesives...

Commercial Use- Chemical substances in packaging, paper..-
Arts, crafts, and hobby materials

Industrial Use- Chemical substances in industrial products-

Paints and...

Processing- Incorporation into an article- Paint additives.

and coating.

Processing-Reactant-(6)..

Commercial Use-Chemical substances in products not described.

by other codes- Laboratory Chemicals

Disposal-

Commercial Use- Chemical substances in electrical products-.

Machinery..

Commercial Use- Chemical substances in metal products-.

Construction...

Manufacturing-Domestic Manufacturing ¦

Commercial Use- Chemical substances in furnishing.

treatment/care products- Construction...

Commercial Use- Chemical Substances in treatment products-

Water...

Commercial Use- Chemical substances in automotive and fuel

products- Automotive...

Commercial Use- Chemical Substances in Furnishing.

treatment/care products- Floor..

Processing- Incorporation into an article- Finishing agents.

in textiles..

| Increasing Risk ]	 O



O
O



OH

O

O o
o
o
O o



O O
O o





~	•

~	•

~	•

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o

o

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o
o

o
o
o
o

<2>
O o
O o
o
OO
O o
o





O
O



Route

• Dermal
O Inhalation

Statistical Descriptor

O Central Tendency
O High-End

0.001

2053

0.010 0.100 1.000 10.000
Acute MOE

2054	Figure 4-1. Acute, Non-cancer Occupational Inhalation and Dermal Risk by TSCA COU

2055	Acute non-cancer MOE risk estimates based on peak occupational exposure estimates (15-minute) with lower

2056	MOE values indicating greater risks. For COUs with multiple OESs or estimation approaches, the estimate with

2057	the highest high-end value was illustrated.

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2058

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2063

Commercial Use- Chemical Substances in treatment products-

Laundry...

Commercial Use-Chemical substances in packaging, _
paper...-Paper products.

Processing- Incorporation into an article-Additive in

rubber-

Commercial Use- Chemical substances in agriculture use

products- Lawn...

Industrial Use- Non-incorporative activities-.

Oxidizing/reducing...

Commercial Use- Chemical substances in outdoor use products-.

Explosive...

Commercial Use- Chemical Substances in treatment products-.

Water...

Commercial Use- Chemical substances in packaging, paper,.

plastic, hobby products-Ink, toner...

Disposal-
Processing- Recycling -
Manufacturing-Domestic Manufacturing -

Processing-Reactant-(6).

Commercial Use- Chemical substances in electrical products-.

Machinery...

Commercial Use- Chemical substances in metal products-.

Construction...

Processing- Incorporation into an article- Finishing agents
3	in textiles...

O

^ Processing of Formaldehyde into Formulations, Mixtures (15)...-

Manufacturing-lmporting -

Processing- Repackaging-Sales.. -

Commercial Use- Chemical substances in packaging, paper...-
Arts, crafts, and hobby materials

Industrial Use- Non-incorporative activities- Used in:.

construction

Commercial Use-Chemical substances in products not described
by other codes- Laboratory Chemicals

Processing- Incorporation into an article- Adhesives...

Commercial Use- Chemical Substances in Furnishing
treatment/care products- Floor...

Commercial Use- Chemical substances in furnishing.

treatment/care products- Construction...

Industrial Use- Non-incorporative activities- Process aid

in: Oil and gas...

Commercial Use- Chemical Substances in construction...-

Adhesives...

Industrial Use- Chemical substances in industrial products-

Paints and...

Processing- Incorporation into an article- Paint additives

and coating...

Distribution- Distribution in Commerce

Commercial Use- Chemical substances in automotive and fuel

products- Automotive...

Increasing Risk j		OO

CO
O O
O O
O O
O O
O O
O O
O

O O
O o

O

O
O
O
O

O

O

O

o
o
o
o
o
O o
O o
o
o
o

o

O o
O o
O o
O

o
o
o

C> o
o

0.001





Statistical Descriptor
O Central Tendency
<0 High-End

Route

O Inhalation

0.010 0.100 1.000

Chronic MOE

10.000

Figure 4-2. Chronic, Non-cancer Occupational Inhalation Risk by TSCA COU

Non-cancer MOE risk estimates based on occupational exposure with lower MOE values indicating greater risks.
For COUs with multiple OESs or estimation approaches, the scenario with the highest central tendency value was
illustrated.

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2064

2065

2066

2067

Commercial Use- Chemical Substances in treatment products-

Laundry...

Commercial Use-Chemical substances in packaging,
paper...-Paper products...

Processing- Incorporation into an article- Additive in

rubber...

Commercial Use- Chemical substances in agriculture use

products- Lawn...

Industrial Use- Non-incorporative activities-
Oxidizing/reducing...

Commercial Use- Chemical substances in outdoor use products-

Explosive...

Commercial Use- Chemical Substances in treatment products-

Water...

Commercial Use- Chemical substances in packaging, paper,
plastic, hobby products-Ink, toner...

Disposal
Processing- Recycling
Manufacturing-Domestic Manufacturing

Processing-Reactant-(6)....

Commercial Use- Chemical substances in electrical products-

Machinery...

Commercial Use- Chemical substances in metal products-

Construction...

Processing- Incorporation into an article- Finishing agents
3	in textiles...

O

^ Processing of Formaldehyde into Formulations, Mixtures (15)...

Manufacturing-Importing -

Processing- Repackaging-Sales..-

Commercial Use- Chemical substances in packaging, paper...-
Arts, crafts, and hobby materials

Industrial Use- Non-incorporative activities- Used in:

construction

Commercial Use-Chemical substances in products not described
by other codes- Laboratory Chemicals

Processing- Incorporation into an article- Adhesives...

Commercial Use- Chemical Substances in Furnishing
treatment/care products- Floor...

Commercial Use- Chemical substances in furnishing
treatment/care products- Construction...

Industrial Use- Non-incorporative activities- Process aid

in: Oil and gas...

Commercial Use- Chemical Substances in construction...-.

Adhesives...

Industrial Use- Chemical substances in industrial products-

Paints and...

Processing- Incorporation into an article- Paint additives

and coating...

Distribution- Distribution in Commerce

Commercial Use- Chemical substances in automotive and fuel

products- Automotive...

O O

-[ Increasing Risk [

o O

O

O O

-•	—

o O
o	O

o O
o O

o

o
o
o
o
o
o

O O
O O
o

o
o
o

o

o

o

o

o
o

0

o

O

O

O

o

O o

O O
~

o
o
o
o

O
O
O

O

icr3	1CT	1 cr-

eancer Risk

O

Statistical Descriptor

O Central Tendency
O High-End

Route
o inhalation

10 '

Figure 4-3. Chronic Cancer Occupational Inhalation Risk by TSCA COU

Cancer risk estimates based on occupational exposure with higher values indicating greater risks. For COUs with
multiple OESs or estimation approaches, the scenario with the highest central tendency value was illustrated.

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4.2.1.2 Overall Confidence in Worker Inhalation Risks

Overall confidence in risk estimates for workers via inhalation exposure varies per COU, depending on
the confidence in the hazard and the exposure assessment for each OES as provided in the Draft
Occupational Exposure Assessment for Formaldehyde (	2024k).

EPA's occupational exposure assessment is supported by a large body of workplace monitoring data
specific to the exposure scenarios assessed. A limitation of the monitoring data is the uncertainty in the
representativeness of the data. Some monitoring data was limited in additional contextual information
such as site identification, worker activities and process conditions, such that EPA used other
information to assign to the respective exposure scenario. For scenarios based on limited monitoring
data, the assessed exposure levels are less likely to be representative of worker exposure across the
entire job category or industry. For many exposure scenarios, EPA incorporates OSHA CEHD data.

This data source does not provide job titles or worker activities associated with the sample. As the
OSHA CEHD data were apportioned to OESs based on their NAICS code, there is an uncertainty in the
representativeness of the mapped OSHA CEHD data for the corresponding exposure scenario.

The effects of these uncertainties on the occupational exposure assessment are unknown, as the
uncertainties may result in either overestimation or underestimation of exposures depending on the
actual distribution of formaldehyde air concentrations and the variability of work practices among
different sites. In some scenarios where monitoring data were available, EPA did not find sufficient data
to determine complete statistical distributions. Ideally, EPA will present 50th and 95th percentiles for
each exposed population. In the absence of percentile data for monitoring, the mean or midpoint of the
range may serve as a substitute for the 50th percentile of the actual distributions. Similarly, the highest
value of a range may serve as a substitute for the 95th percentile of the actual distribution. However,
these substitutes are uncertain. The effects of these substitutes on the occupational exposure assessment
are unknown, as the substitutes may result in either overestimation or underestimation of exposures
depending on the actual distribution. Although the weight of scientific evidence varies, EPA has
concluded that the underlying data still provide plausible estimates of exposures for all OESs.

EPA has medium confidence in the acute inhalation POD. It is based on evidence in healthy adults in
controlled exposures. Generally, EPA has medium confidence in the exposure estimates for peak
exposures, but it varies from low to high across the OESs assessed. For most exposure scenarios, EPA
estimated peak exposures using 15-minute workplace monitoring data from the OSHA CEHD database.
However, in some cases, EPA may not have information on the worker activities sampled and whether
these activities would be expected to result in peak levels of formaldehyde. For many scenarios, there is
a high level of non-detects integrated within exposure estimates, which can bias the exposure estimate.
Generally, the limit of detection for the 15-minute samples were higher than the calculated occupational
exposure value for acute effects (see Appendix E. 1). For example, acute risks are greatest for the below
COUs, in which EPA has an overall medium confidence in the individual risk estimates:

• Commercial use - chemical substances in automotive and fuel products - automotive care
products; lubricants and greases; fuels and related products: EPA has medium confidence in
the risk estimates for this COU. Three occupational exposure scenarios are estimated for this
COU, the exposure scenario with the highest central tendency exposure estimate was selected for
risk characterization of this condition of use. The automotive care products OES was modeled
for the worker activity of applying a detailing product containing formaldehyde. The scenario
was modeled using two approaches: an approach that model complete evaporation of the
expected formaldehyde contained in the detailing product during application, and an approach
using measured VOC data. To account for variability, EPA performed 100,000 Monte Carlo

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iterations where parameters were varied based on industry defaults such as number of cars
detailed per site, amount of product used, and formaldehyde specific information, concentration
of formaldehyde in the product. EPA calculated vapor generation using the chemical properties
of formalin as well as reported VOC emissions in the automotive detailing industry. A limitation
of this modeled estimate is that it does not account for if any engineering controls are used
during application.

•	Manufacturing-manufacturing: EPA has medium confidence in the risk estimates for this
COU. Acute inhalation risk estimates were derived using 15 personal breathing zone sample data
collected at two U.S. formaldehyde manufacturing facilities in 1992 and one U.S. formaldehyde
manufacturing facility in 2020. Due to a limited amount of recent monitoring data, there is some
uncertainty in the representativeness of the estimates at current manufacturing facilities.

For chronic inhalation risks, EPA has medium confidence in the cancer inhalation unit risk underlying
these risk estimates and high confidence in the chronic, non-cancer hazard POD. The chronic, non-
cancer hazard POD is supported by a robust database of evidence in humans and animals that
demonstrates concordance in effect levels across multiple endpoints and it includes evidence in children
with asthma and other sensitive groups.

Generally, EPA has medium confidence in the exposure estimates for full-shift exposures but confidence
for individual scenarios varies from low to high across the OESs assessed. For most exposure scenarios,
EPA estimated full-shift exposures by integrating discrete data identified from peer-reviewed literature
and other sources. As discussed earlier, OSHA CEHD does not provide all of the meta-data associated
with the sampled data. For estimation of full-shift exposures, EPA establish a cut-off total sampling
duration of 5.5 hours to reduce uncertainties by using data most expected to represent full-shift
exposures. EPA then calculated an 8-hour TWA assuming that unsampled time was zero. This approach
may lead to underestimation of full-shift exposures if workers were still exposed to formaldehyde for the
unsampled time. A sensitivity analysis on these assumptions were included in the Draft Occupational
Exposure Assessment for Formaldehyde (	24k).

For calculation of the ADC and LADC, EPA assumes that workers are exposed for 250 days per year for
chronic and 22 days per month for sub-chronic risk estimates across all scenarios. For LADC, the
assumption of worker tenure is important, in which EPA uses 31 years for central tendency risk
estimates and 40 years for high-end risk estimates. These parameters may vary by individual workers. A
principal limitation of the ADC and LADC used is that these exposure estimates assume no exposure to
formaldehyde outside of the workplaces. In Section 4.3, EPA considers how aggregate exposures to
formaldehyde from multiple sources, across multiple routes, or across pathways may increase the overall
risk for some people.

Although the weight of scientific evidence varies, EPA has concluded that the underlying data still
provide plausible estimates of exposures for all OESs. As examples, chronic risks are greatest for the
below COUs, in which EPA has an overall medium confidence in the risk estimates:

•	Commercial use - chemical substances in automotive and fuel products - automotive care
products; lubricants and greases; fuels and related products: EPA has medium confidence in
the risk estimates for this COU. Three occupational exposure scenarios are estimated for this
COU, the exposure scenario with the highest central tendency exposure estimate was selected for
risk characterization of this condition of use. The automotive care products OES was modeled
for the worker activity of applying a detailing product containing formaldehyde. The model
assumes that as the detailing product containing formaldehyde is applied, that the formaldehyde
evaporates during application. To account for variability, EPA performed 100,000 Monte Carlo

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iterations where parameters were varied based on industry defaults such as number of cars
detailed per site, amount of product used, and formaldehyde specific information, concentration
of formaldehyde in the product. A limitation of this modeled estimate is that it does not account
for if any engineering controls are used during application. EPA calculated vapor generation both
using the chemical properties of formalin as well as reported VOC emissions in a similar
industry.

• Processing - processing as a reactant (COU Group): EPA has medium to high confidence in
the risk estimates for this COU. The underlying occupational exposure scenario covers, in
general, processes that use formaldehyde as a reactant for a variety of downstream products. This
scenario integrates data from a variety of sources (e.g., industry submissions, OSHA CEHD
data) for a total of 192 8-hr TWA samples. Limitations within the monitoring data is a lack of
additional details on worker activities for the individual samples. There is some uncertainty on
the representativeness of the 50th and 95th percentiles towards the true distribution for the
exposed population for this scenario.

4.2.1.3	Risk Estimates for Dermal Exposures

Acute non-cancer risk estimates for dermal exposure range from 3.24x10 3 to 18 (benchmark MOE of
10) for central tendency exposures and high-end exposures. Risk estimates are greatest for TSCA COUs:
Commercial use - chemical substances in automotive and fuel products - automotive care products;
lubricants and greases; fuels and related products; and TSCA COUs: Processing - incorporation into an
article - paint additives and coating additives not described by other categories in transportation
equipment manufacturing (including aerospace); Industrial use - paints and coatings; adhesives and
sealants; lubricants; commercial use - chemical substances in construction, paint, electrical, and metal
products - adhesives and sealants; paint and coatings. Both OESs assumed an immersive dermal loading
on the skin during the exposure scenario.

Dermal risk estimates were not provided for Distribution in commerce and commercial use - packaging,
paper, and hobby products COUs. These COUs involve the handling of solid articles with low
concentrations of formaldehyde in which the dermal modeling approaches were not suitable. EPA
expects the primary concern for these products is inhalation exposures from formaldehyde off-gassing.

4.2.1.4	Overall Confidence in Worker Dermal Risks

Overall confidence in risk estimates via dermal exposure is medium. As described in Section 3.2, overall
confidence in the dermal hazard value is medium. As described in Section 2.5.1, overall confidence in
dermal occupational exposures is medium based on a moderate weight of scientific evidence for all
scenarios assessed. All scenarios used a modified version of the EPA Dermal Exposure to Volatile
Liquids Model, which reduced to two parameters: an activity-based dermal loading and a maximum
weight concentration of formaldehyde in the formulations handled. For many scenarios, maximum
concentration information from sources such as the 2020 CDR (	»20b) have overall data

quality determinations of either high or medium from EPA's systematic review process. Some scenarios
lacked sufficient information on the maximum concentrations expected and industry-specific or
surrogate scenarios were used to inform calculations. There is some uncertainty on the range of
concentrations of formaldehyde within certain processes and products whose impact is unknown and
may either result in an overestimation or underestimation of exposures.

4,2.2 Risk Estimates for Consumers	

EPA estimated cancer and non-cancer risks for exposure to formaldehyde resulting from exposure to
formaldehyde in consumer products. For this analysis, EPA relied on the consumer exposure estimates

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modeled in the Draft Consumer Exposure Assessment for Formaldehyde (	Z4d) and

summarized in Section 2.2.

4.2.2.1 Risk Estimates for Inhalation Exposure to Formaldehyde in Consumer
Products

EPA estimated cancer and non-cancer risks to consumers and bystanders from inhalation of
formaldehyde in consumer products.

Acute inhalation risk estimates range from 4.65 xl0~4 to 1.31 (Figure 4-4). These acute risk estimates are
calculated using high-end air concentrations modeled for a 15-minute period based a set of high-end
model input assumptions and TSCA COU-specific assumptions about exposure frequency and duration.
Acute risk estimates below 1 indicate that exposure is greater than the hazard point of departure
identified for 15-minute peak exposures based on sensory irritation reported in controlled human
exposure studies in healthy adult volunteers.

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Floor coverings; Foam seating and bedding
products; Cleaning and furniture care products;
Furniture & furnishings including stone, piaster,
cement, glass and ceramic articles; metal
articles; or rubber articles

Adhesives and Sealants; Paint and coatings

Paper products; Plastic and rubber products; Toys,
playground, and sporting equipment

3

o
o

Ink, toner, and colorant products; Photographic

supplies

Construction and building materials covering
large surface areas, including wood articles;
Construction and building materials covering
large surface areas, including paper articles;
metal articles; stone, plaster, cement, glass and
ceramic articles

Automotive care products; Lubricants and greases;

Fuels and related products

Fabric, textile, and leather products not covered
elsewhere (clothing)





Increasing risk



+

+



















* ~ +













Zone
• Far Field





+





* Near Field
¦ Zone 1
+ Zone 2





,

. 1 . . . .

. 1 . . . .



10"

10"

Peak 15-min Inhalation MOE

10"

Figure 4-4. Peak 15-Minute Inhalation Risk by COUs in Consumer Products

Acute non-cancer risk estimates are based on high-end consumer and bystander exposure estimates. Acute non-cancer MOEs are based on modeled air
exposure estimates and are interpreted relative to a benchmark MOE of 10. Lower MOE values indicate greater risks. For some products, air
concentrations were modeled for near-field and far-field (generally describing differences in exposure within the same room) while for other products
concentrations were modeled for zones 1 and 2 (generally describing different rooms). Risks from near-field and zone 1 exposures generally represent
risks from direct exposures to consumer users while far-field and zone 2 tend to represent risks to consumer bystanders. For instance, an individual
applying floor coverings: Varnishes and floor finishes in a living room can be described as a consumer of that product in zone 1 or near-field of the
application area. On the other hand, while the product is being applied there may be someone else either also in the room of use and assumed to be away
from the immediate application area (or in the far-field), or in a completely different room from where the product is being applied (also known as zone 2).
The x-axis presents the 15-minute peak inhalation non-cancer concentration, and the y-axis presents the modeled TSCA COUs.

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Chronic non-cancer risk estimates for consumers based on modeled chronic inhalation exposures range
from 5.70x 10_1 to 7.64, with lower values indicating greater risks (Figure 4-5). Non-cancer risk
estimates below 1 indicate that exposure is greater than the hazard point of departure based on
respiratory effects in sensitive groups, including children. Chronic ADAF-adjusted lifetime cancer risk
estimates based on modeled chronic inhalation range from 2.36xl0~u to 4.82xl0~4 (Figure 4-6), with
larger numbers indicating increasing risk. The risk estimates for chronic exposures presented here are
based on central tendency air concentrations modeled for a set of mid-range model input assumptions
and TSCA COU-specific assumptions about exposure frequency and duration. Risk estimates presented
here represent risks to consumers who frequently use products containing formaldehyde and are based
on the consumer activity and use patterns described in the Draft Consumer Exposure Assessment for
Formaldehyde (U.S. EPA. 2024d). For example, cancer risk estimates for the arts, crafts, and hobby
material COU presented here are not representative of all arts and crafts products. They are based on an
assumption of exposure to a specific set of products that contain 0.1 percent formaldehyde used an
average of 15 minutes/day, 300 days each year, over a period of 57 years which are standard CEM
temporal inputs primarily based upon the 1987 Westat survey of consumer activities and use patterns
(U.S. EPA. 2021a. 2019; Westat. 1987V

Adhesives and Sealants; Paint and coatings

Arts Crafts and Hobby Material

O
o

Ink, toner, and colorant products; Photographic

supplies

Floor coverings; Foam seating and bedding
products; Cleaning and furniture care products;
Furniture & furnishings including stone, plaster,
cement, glass and ceramic articles; metal
articles; or rubber articles

Automotive care products; Lubricants and greases;

Fuels and related products







Increasing risk

o













Modeled Person
~ Bystander
O User



o

















o



~













o



~











	

. 		

¦

10

Chronic MOE

100

Figure 4-5. Chronic Non-cancer Inhalation Risks for Consumer Products by COU

Chronic risk estimates are based on consumer and bystander exposure estimates that rely on central tendency
assumptions about product use duration and frequency. Non-cancer MOEs are based on modeled air exposure
estimates and are interpreted relative to a benchmark MOE of 3. Lower MOE values indicate greater risks. The x-
axis presents risk estimates for chronic inhalation exposure estimates, and the y-axis presents the modeled TSCA
COUs.

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Increasing risk













W

Arts Crafts and Hobby Material ¦







o







Ink, toner, and colorant products; Photographic,





~

o

supplies





cou











Floor coverings; Foam seating and bedding
products; Cleaning and furniture care products;
Furniture & furnishings including stone, plaster, ¦
cement, glass and ceramic articles; metal
articles; or rubber articles





~ O













Automotive care products; Lubricants and greases; _

0

1	1 i i i i





Modeled Person
~ Bystander
O User



Fuels and related products

i i . i i i i .

. . i

¦ i i ¦ 1 ¦

»

10"6	10"5	10~4

ADAF-Adjusted Lifetime Cancer Risk

Figure 4-6. ADAF-Adjusted Chronic Inhalation Cancer Risk by COUs in Consumer Products

ADAF-adjusted lifetime cancer risk estimates are based on consumer and bystander central tendency exposure
estimates. Higher cancer risk estimates indicate greater risk. The x-axis presents the ADAF-adjusted lifetime
cancer risk and the y-axis presents the modeled TSCA COUs.

Overall confidence in inhalation risk estimates for consumer products is medium for chronic non-cancer
risks and medium for cancer risk and acute non-cancer risk. As described in Section 3.2.1.1 of the
Consumer Exposure Module, the overall confidence in monitoring data used in the indoor air assessment
is high due to reliance on 41 high quality formaldehyde air exposure studies relevant to TSCA COUs,
and CEM modeling assumptions and inputs, which have been peer reviewed and used in previous
existing chemical risk evaluations. While EPA relied on available survey data on product use patterns,
there is uncertainty around the applicability of the generic survey data for current use patterns for
specific product types. For example, for some inputs relied on the use and activity patterns reported in
the Westat survey from 1987 (Westat 1987). Although this is a robust dataset it may not be reflective of
current use patterns for the specific product types assessed. As described in Section 3.2, overall
confidence in the chronic, non-cancer hazard POD is high because it is supported by a robust database of
evidence in humans and animals that demonstrates concordance in effect levels across multiple
endpoints and it includes evidence in children with asthma and other sensitive groups. Overall
confidence in the inhalation unit risk for formaldehyde is medium. The cancer risk estimates presented
here do not include risks for some of the tumor sites. While the draft IRIS assessment concluded that the
evidence demonstrates that formaldehyde inhalation causes myeloid leukemia and sinonasal cancer in

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humans, EPA was not able to quantify those risks with confidence. The draft IRIS assessment estimated
that the IUR used to estimate lifetime cancer risks may underestimate total cancer risk by as much as 4-
fold. EPA has medium confidence in the acute inhalation POD based on evidence in healthy adult
volunteers in controlled exposure conditions.

4.2.2.2 Risk Estimates for Dermal Exposure to Formaldehyde in Consumer Products

EPA estimated non-cancer risks for acute dermal exposure to formaldehyde in consumer products.

Dermal risk estimates were calculated based on low, central tendency and high-end exposure estimates.
The estimated dermal risks based on high-end exposures range from 3.24x10 3 to 9.71 and are presented
in Figure 4-7. Risk estimates below 1 indicate that exposures are above the POD based on skin
sensitization responses observed in adults. There is uncertainty surrounding the assumption of occlusion
or immersion of hands using liquid or spray consumer products, which may overestimate exposures and
risks for some consumer exposure scenarios.

Polish and wax - (Exterior Car Wax and _
Polish)

Photographic Supplies - (Liquid photographic^
processing solutions)

eg
c

o
CO
"D

"O

O

Cleaning and Furnishing Care Products -
(Drain and Toilet Cleaners)

Adhesives and Sealants - (Glues and
Adhesives, small or large scale)

Building / Construction Materials - (Liquid-
based concrete, cement, plaster (prior to
hardening))

Arts, Crafts, and Hobby Materials - (Crafting
Paint (direct and incidental contact))





Increasing risk























































Modeled
Exposure Level

~ High



, , 1 ,

, ,,

¦ ¦





10"

10"'

Acute Dermal MOE

10"

Figure 4-7. Acute Dermal Loading Risk by High-End Exposure Scenarios in Consumer Products

Dermal non-cancer MOE risk estimates are based on consumer exposure estimates and are interpreted relative to a
benchmark MOE of 10. Lower MOE values indicate greater risks. The x-axis presents the acute dermal loading
MOE, and the y-axis presents the modeled scenarios written as TSCA COU followed by relevant exposure
scenario in parentheses.

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Overall confidence in risk estimates for dermal exposure is medium. As described in Section 3.2.1.1 of
the Consumer Exposure Module, the overall confidence in monitoring data used in the indoor air
assessment is medium due to no formaldehyde dermal exposure studies identified through systematic
review; though other highly rated supplemental studies were used to identify loading of formaldehyde to
skin (U.S. EPA. 2019; Delmaar et JO i i'H S. 2002; AT SDK	and product specific modeling

assumptions and weight fractions identified via safety data sheets reviewed and used in previous existing
chemical risk evaluations. As described in Section 3.2, overall confidence in the dermal hazard value is
medium.

4,2.3	Risk Estimates for Indoor Air	

EPA estimated cancer and non-cancer risks for exposure to formaldehyde in indoor air. For this analysis,
EPA considered available indoor air monitoring data as well as air concentrations modeled based on
specific TSC A COUs, as described in the Draft Indoor Air Assessment for Formaldehyde (
2024D. Monitoring data provide an indication of aggregate exposure and risks in a range of indoor
environments while modeled air concentrations can provide information about the contributions of
specific TSCA COUs to indoor air concentrations.

4.2.3.1 Risk Estimates Based on Indoor Air Monitoring Data

Monitoring data provide information about actual concentrations of total formaldehyde in indoor air, but
the data reflect aggregate concentrations from all TSCA and other sources present. Monitoring data are
therefore a good indication of aggregate formaldehyde exposures and risks in a range of indoor
environments, but do not provide information about the relative contributions of each source.

EPA estimated cancer and non-cancer risks based on levels of formaldehyde detected in indoor air in
monitoring studies representing a range of indoor air environments. The American Healthy Home
Survey II is a survey published in 2021 that is representative of residential indoor air conditions across a
wide range of American households (OuanTech. 2021). It is the most current nationally representative
survey of formaldehyde in indoor air in American homes and is likely the best representation of the
current range of aggregate exposures and risks from all sources of formaldehyde in indoor air. Other
monitoring datasets considered in this analysis generally target indoor environments that typically have
higher formaldehyde concentrations, such as trailers and mobile homes. Available indoor air monitoring
datasets likely do not represent current conditions in indoor air following Title VI regulation of wood
products. Figure 4-8 summarizes ADAF-adjusted lifetime cancer risk estimates based on indoor air
monitoring data, relying on the assumption that these monitored concentrations could represent average
exposures in indoor air and that exposure to these concentrations may be experienced continuously over
a 78-year lifetime. This may be a conservative assumption for high end indoor air exposures, as
concentrations in a particular home change over time and people typically live in multiple homes over
the course of their lives.

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D
o

i_

=s
o
CO

-5

"to
Q

D)

Maddalena, 2008: 4 FEMA camper trailers ¦ .

Murphy, 2013: All structures (519) -

Murphy, 2013: Travel trailers (360) -

Murphy, 2013: Mobile homes (69) -

Murphy, 2013: Park models (90) ¦

Offermann, 2008 : 108 new SF homes in CA-

Sax, 2004: Inner-city homes-

American Healthy Home Survey: Various -

Gilbert, 2006: 96 homes in Quebec City, Canada ¦
Gilbert, 2005: 59 homes in Prince Edward Island,.

Canada

Hodgson, 2000: 7 new site-built homes ¦

Hodgson, 2000: 4 new manufactured homes -

Sax, 2004: Los Angeles (41) -winter ¦

Sax, 2004: NY City (46) summer-

Hodgson, 2000: New homes in eastern/SE U.S -

Liu, 2006: Elizabeth, NJ; and Houston, TX-
California Air Resources Board (CARB), 2004: _
Portable Classroom
Sax, 2004: Los Angeles (41) fall -
California Air Resources Board (CARB), 2004: _
Traditional Classroom
Sax, 2004: NY City (46) - winter-

Liu, 2006: 234 homes in Los Angeles County, CA-

Hodgson, 2004: 4 new relocatable classrooms -

Increasing risk

Metric

Range
~ Central Tendency

10"5	10""	10"

ADAF-Adjusted Lifetime Cancer Risk

10"

Figure 4-8. ADAF-Adjusted Lifetime Cancer Inhalation Risk by Indoor Air Monitoring Data
Source

Cancer risk estimates are based on air concentrations reported in monitoring data and rely on the
assumption that individuals may be consistently exposed to these concentrations over a 78-year lifetime.
Higher cancer risk estimates indicate greater risk. Air monitoring data sources listed on the y-axis are
described in more detail in the Draft Indoor Air Assessment for Formaldehyde (U.S. EPA. 2024iY

Among all residence types and commercial environments, lifetime cancer risk estimates based on indoor
air monitoring data ranged from 2.74><10H5 to 9.46x10 3. These ranges of risk estimates correspond to
measured minimum concentrations of 2.18x 10~4 ppm by the American Healthy Home Survey II
(OuanTech. 20211 and a measured maximum concentration of 7.53 x 10_1 ppm from a study of four
FEMA camper trailers (LBNL. 2008). respectively. Chronic non-cancer risk estimates based on the
same indoor air monitoring data range from 77.8 to 0.02, with lower values indicating greater risk.

4.2.3.2 Risk Estimates Based on Indoor Air Modeling for Specific TSCA CPUs	

Indoor air concentrations modeled for specific COUs provide an indication of the contributions of
individual COUs to formaldehyde exposure and risk. EPA estimated chronic non-cancer risks based on
formaldehyde concentrations modeled based on long-term emissions associated with specific COUs, as
described in Section 2.3. The modeled air concentrations used as the basis for chronic risk estimates for
indoor air were designed to estimate concentrations at the central tendency. As described in the Draft
Indoor Air Exposure Assessment for Formaldehyde (U.S. EPA. 2024i). there is substantial uncertainty
related to the degree of dissipation of formaldehyde over time and how exposures from specific products
change over the course several years. For this reason, EPA has low confidence in exposure estimates
modeled over longer than a year for specific TSCA COUs contributing to formaldehyde in indoor air.

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EPA therefore did not calculate cancer risk based on chronic indoor air exposures resulting from specific
TSCA COUs.

Non-cancer risk estimates based on indoor air concentrations modeled for specific COUs range from
0.05 to 4. Risk estimates below 1 indicate that exposure is greater than the hazard point of departure
based on respiratory effects in sensitive groups, including children. Figure 4-9 summarizes chronic non-
cancer risk estimates based on modeled average indoor air concentrations estimated to result from
specific TSCA COUs over the course of the first year of product use. These risk estimates account for
dissipation that occurs over time due to the depletion of formaldehyde from the article and air exchange
but do not account for the half-life of formaldehyde.

Construction and building materials covering
large surface areas, including wood articles;
Construction and building materials covering _
large surface areas, including paper articles;
metal articles; stone, plaster, cement, glass and

ceramic articles

Floor coverings; Foam seating and bedding
products; Cleaning and furniture care products;
Furniture & furnishings including stone, plaster,
cement, glass and ceramic articles; metal
articles; or rubber articles

D

o
o

Paper products; Plastic and rubber products; Toys,
playground, and sporting equipment

Fabric, textile, and leather products not covered _

elsewhere





Increasing risk















Environment

± Residential





A















1 . . . ,

. l 	

, , ,

0.1

1.0

Chronic MOE

Figure 4-9. Chronic Non-cancer Inhalation Risk Based on Modeled Air Concentrations for
Specific TSCA COUs

Chronic non-cancer risk estimates are based on indoor air exposure estimates. Lower MOEs indicate greater risk.
The y-axis presents the modeled scenarios written as TSCA COU followed by relevant exposure scenario.

Overall confidence in risk estimates by individual TSCA COU modeling is medium. In general, EPA
has medium confidence in CEM's ability to assess formaldehyde exposures in indoor air and the
supporting monitoring data. The inability to account for half-life in the model decreases confidence in
the exposure estimates. It is unclear whether the modeling results are reflective of most indoor air home
environments in American residences. EPA has medium confidence in the applicability of the modeling
results used to assess indoor air exposures to formaldehyde. As described in Section 3.2.1.1 of the Draft
Indoor Air Exposure Assessment Module, the overall confidence in modeling used in the indoor air
assessment is high due to medium quality studies used to incorporate TSCA COU-specific emission

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rates and due to the use of a high quality CEM modeling inputs and formulas used to generate TSCA
COU-specific indoor air concentrations.

Monitoring data reflect total concentrations from a wider range of sources and are therefore not directly
comparable to modeled estimates. However, in general, modeled and monitored indoor air formaldehyde
concentrations are within the same order of magnitude that increases the confidence in the modeled
formaldehyde indoor air exposures underlying these risk estimates.

As described in Section 3.2, overall confidence in the chronic non-cancer hazard POD is high. It is
supported by a robust database of evidence in humans and animals that demonstrates concordance in
effect levels across multiple endpoints and it includes evidence in children with asthma and other
sensitive groups.

4.2.3.3 Integration of Modeling and Monitoring Information and Consideration of
Aggregate Risk

Risk estimates based on modeled air concentrations provide information about the contribution of
specific COUs to exposures and risks from formaldehyde in indoor air. However, given the ubiquity of
formaldehyde in indoor environments, risks from individual sources rarely occur in isolation. EPA has
therefore also considered monitoring data as an indication of aggregate exposure and risks from all
sources contributing to formaldehyde in indoor air.

While monitoring data does not distinguish between risk contributions from TSCA and other sources, it
offers a way to interpret risks from individual COUs in the context of aggregate risks from all co-
occurring sources.

As previously noted, the AHHS II is the most current nationally representative survey of formaldehyde
in indoor air in American homes. Therefore, among all monitoring sources, it is likely the most
appropriate source for the estimation of aggregate risks in American residential indoor air across all
households, including old and new homes. Using the maximum estimated monitoring indoor air estimate
for formaldehyde in AHHS II (including contributions from both TSCA and other sources), it may be
assumed that indoor air aggregate non-cancer MOEs are as low as 1.681 xlO-1 and cancer MOEs are as
high as 1.271x10 3 in typical U.S. The same can be inferred from mobile home, classroom, and other
monitoring indoor air risk estimates.

4,2,4 Risk Estimates for Ambient Air

EPA evaluated cancer risks resulting from human exposure to formaldehyde via the ambient air pathway
using previously peer-reviewed methodologies along with multiple lines of evidence including multiple
release estimates from two separate databases (TRI and NEI), several peer-reviewed models (IIOAC,
HEM, AirToxScreen), and monitoring data (AMTIC) from EPA's ambient monitoring network. When
looking at direct analysis of formaldehyde release data from TRI using IIOAC to represent a more
localized exposure, 26 of 29 TSCA COUs evaluated have risk estimates greater than 11 x 10~6, and 19
COUs have risk estimates greater than 11 x 10~5. Additionally, 21 of the 29 TSCA COUs have risk
estimates greater than relative risk estimates for biogenic sources. As expected, modeled concentrations
using IIOAC fall within the lower range of monitoring data from AMTIC (although not amortized as
annual averages) since AMTIC represents a total formaldehyde concentration from all sources rather
than localized impacts near industrial facilities releasing formaldehyde to the ambient air and associated
with COUs evaluated with IIOAC. Nonetheless, cancer risk estimates based on monitoring data from
AMTIC range from 7.11 x 10~8 to 6.1 x 10~4. Figure 4-10 shows the ADAF-adjusted cancer risk estimates
for all AMTIC monitoring data, IIOAC modeled data, and AirToxScreen modeled data, based on the

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assumption that these concentrations reflect average exposures that occur continuously over a 78-year
lifetime.

AMTIC (Monitoring)
(N=199,466)

IIOAC (Modeled)
(N=35)

AirTox Total Sources (Modeled)
(N=76,726)

c/>

ro AirTox Point Sources (Modeled)
O	(N=76,364)

AirTox Biogenic Sources (Modeled)
(N=76,726)

AirTox Secondary Sources (Modeled)
(N=76,726)

Data Source

• AMTIC (Monitoring) • AirTox (Modeled) • IIOAC (Modeled)

Figure 4-10. A DA F-Adj usted Cancer Risk for Monitoring and Modeling Ambient Air Data

EPA recognizes that the different model estimates are not directly comparable. For example, the IIOAC
results represent a risk estimate between 100 to 1,000 m from the release point. In contrast,
AirToxScreen concentrations represent risk estimates at the census tract scale; only point source data
may represent some releases of formaldehyde from TSCA COUs. Given the spatial scale difference, it is
expected that AirToxScreen results could underestimate concentrations on a smaller scale (i.e., near
facilities) or have lower concentration estimates than IIOAC and this difference can be seen in Figure
2-10. Additionally, only point source data within AirToxScreen may represent a broader set of
formaldehyde releases that include releases associated with TSCA COUs.

4.2.4.1 Risk Estimates Based on Ambient Air Monitoring

There is abundant monitoring data on formaldehyde in ambient air. As described in Section 2.4.1,
monitoring data from EPA's AMTIC (J.S. EPA. 2022a) include a range of air monitoring data collected
across the country under a range of experimental designs across heterogenous environments. EPA
considers the available monitoring data for formaldehyde to reflect the range of aggregate formaldehyde
concentrations under a range of outdoor environments from both TSCA and other sources of
formaldehyde.

EPA calculated chronic cancer risks based on air concentrations reported in AMTIC, relying on the
assumption that monitored concentrations could represent chronic exposure (as shown at the top of
Figure 4-10). However, because some monitoring efforts included in the dataset capture a snapshot of
air concentrations at a single timepoint, there is uncertainty around the extent to which the available
monitoring data are an accurate representation of long-term chronic exposures.















¦

1 ,1







	 1 ,







^0 ts	^0 s	^0 6	6' ^'Or, ^0 ¦!

V

ADAF-Adjusted Risk

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Given the ubiquity of formaldehyde and the diversity of sources, monitoring data does not provide clear
information on the contributions of specific TSCA or other sources of formaldehyde. Risk estimates
based on the available monitoring data provide an indication of the aggregate risk from all sources
contributing to ambient air concentrations of formaldehyde, which may be present in the real world and
provide context for risks from individual TSCA COUs.

4.2.4.2 Risk Estimates Based on Modeled Concentrations near Releasing Facilities

EPA estimated risks associated with acute and chronic non-cancer exposure to formaldehyde in the
ambient air. EPA utilized the 95th percentile release value reported to TRI by Industry Sector (mapped
to respective COUs) and the 95th percentile modeled annual-averaged air concentrations from the
IIO AC output file at 100 to 1,000 m from the release point as described in the Draft Ambient Air
Exposure Assessment for Formaldehyde (	24a) to derive risk estimates. All derived risk

estimates for acute and chronic non-cancer effects were above relative MOE benchmarks. Therefore,
while all risk estimates are included in the "Draft IIO AC Assessment Results and Risk Calcs
Supplement A for Ambient Air," EPA focuses on cancer risk estimates as described below for purposes
of risk characterization in this draft human health risk assessment.

EPA estimated cancer risks associated with continuous chronic exposure to formaldehyde in the ambient
air over a 78-year lifetime. EPA utilized the 95th percentile release value reported to TRI by Industry
Sector (mapped to respective TSCA COUs) and the 95th percentile modeled annual-averaged air
concentrations from the IIO AC output file at a distance of 100 to 1,000 m from the release facility
described in the Draft Ambient Air Exposure Assessment for Formaldehyde (	2024a) and in

Section 2.4.2.1, to derive cancer risk estimates. Risk estimates are presented by TSCA COU in Figure
4-11. As described in Section 4.1.2, higher cancer risk estimates indicate higher risks.

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Processing as a reactant-lntermediate -
Processing-Repackaging -
Processing-Recycling -
Processing-Reactant-intermediate -
Processing-Reactant-Bleaching Agent -
Processing-Reactant-Adhesive and Sealant Chemicals -
Processing-Incorporation into Article-Finishing Agents -
Processing-Incorporation into article-Adhesive and sealants -
Processing-Incorporation into Article-Additive
Processing-Incorporation into an Article-Paint additives and coating additives
Processing-Incorporation into a formulation, mixture, or reaction product-Surface Active Agents
Processing-Incorporation into a formulation, mixture, or reaction product-Solvents (which become part of a product formulation or mixture) -

Processing-Incorporation into a formulation, mixture, or reaction product-Solid separation agents
Processing-Incorporation into a formulation, mixture, or reaction product-Processing aids, specific to petroleum production
Processing-Incorporation into a formulation, mixture, or reaction product-Plating agents and surface treating agents -
~ Processing-Incorporation into a formulation, mixture, or reaction product-Paint additives and coating additives not described by other categories -

d)
C/3

=3

c
o

o

O

Processing-Incorporation into a formulation, mixture, or reaction product-Lubricant and lubricant additive -
Processing-Incorporation into a formulation, mixture, or reaction product-Ion exchange agents -
Processing-Incorporation into a formulation, mixture, or reaction product-Intermediate -
Processing-Incorporation into a formulation, mixture, or reaction product-Bleaching Agents -
Processing-Incorporation into a formulation, mixture, or reaction product-Agricultural chemicals (Nonpesticidal) -
Processing-Incorporation into a formulation, mixture, or reaction product-Adhesive and Sealant Chemicals

Processing- Incorporation into a formulation, mixture, or reaction product

Manufacturing-Importing
Industrial Use-Non-incorporative activities-Used in: construction
Industrial Use-Non-incorporative activities-Oxidizing/reducing agent; processing aids, not otherwise listed -
Industrial Use-Chemical substances in industrial products-Paints and coatings; adhesives and sealants, lubricants -

Domestic Manufacturing -
Disposal -

10	10	10

ADAF-Adjusted

10

Cancer Risk

106 10'
Estimate

Figure 4-11. Risk Estimates by TSCA COU for the 95th Percentile Release Scenario and 95th Percentile Modeled Concentration
between 100 and 1,000 in from Industrial Facilities Releasing Formaldehyde to the Ambient Air

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Across all TSCA COUs, cancer risk estimates ranged from 1.1 x 10~9 to 5.9x 10~5. The three highest
cancer risk estimates are 5.9xl0~5, 4.5xl0~5, and 3.4xl0~5. These three cancer risk estimates represent
three industry sectors and seven TSCA COUs.

The three industry sectors with the highest cancer risk estimates associated with TSCA COUs are:

•	Non-metallic mineral product manufacturing (5.9x 10~5);

•	Textiles, apparel, and leather product manufacturing (4.5 x 10~5); and

•	Transportation equipment manufacturing (3.4 x 10~5).

Together, these three industry sectors are associated with seven formaldehyde TSCA COUs {i.e.,
individual industry sector results are used to represent multiple formaldehyde TSCA COUs as shown
below). Those COUs are:

•	Processing - incorporation into an article-adhesives and sealant chemicals (5.9x10-5);

•	Processing as a reactant-intermediate (5.9x 10~5);

•	Processing - incorporation into a formulation, mixture, or reaction product-intermediate
(5.9xl0~5);

•	Processing - incorporation into article-finishing agent (4.5 x 10~5 |ig/m3);

•	Processing - incorporation into a formulation, mixture, or reaction product-bleaching agents
(4.5xl0~5);

•	Processing-incorporation into an article-paint additives and coating additives (3.4x 10~5); and

•	Industrial use-chemical substances in industrial products-paints and coatings; adhesives and
sealants, lubricants (3.4xl0~5).

In total, 19 of the 29 TSCA COUs (65.5%) have cancer risk estimates within the same order of
magnitude greater than 1 x 10~5. An additional seven TSCA COUs have cancer risk estimates within the
same order of magnitude greater than 1 x 10~6 and less than 1 x 10~5. Two COUs have cancer risk
estimates within the same order of magnitude greater than 1 x 10~7 and less than 1 x 10 (\ and one TSCA
COU has a cancer risk estimate in the 1 x 10~9 range.

Recognizing the ubiquity of formaldehyde in ambient air occurs from multiple sources including other
sources like biogenic/natural sources and secondary formation, EPA compared the calculated risk
estimates for modeled concentrations from IIOAC to the calculated risk estimate for the 95th percentile
concentration of attributable to biogenic sources. Across all 29 TSCA COUs evaluated, 21 TSCA COUs
have risk estimates greater than the risk estimate for biogenic sources (2.85 x 10~6). Eighteen TSCA
COUs have calculated risk estimates greater than 5 times the calculated risk estimate for biogenic
sources (1.42xl0~5). Seven TSCA COUs have calculated risk estimates greater than 10 times the
calculated risk estimate for biogenic sources (2.85xl0~5). Eight TSCA COUs have calculated risk
estimates less than the risk estimate for biogenic sources.

For the industry sector of Oil and Gas Drilling, Extraction, and Support Activities, results were not
available from the TRI program. Although many of the NAICS codes for this industry sector are not
covered by the TRI program, the sites are well represented in the NEI database. This industry sector is
associated with the following formaldehyde TSCA COUs:

•	Processing as a reactant-functional fluid;

•	Processing - incorporation into a formulation, mixture, or reaction product - processing aids,
specific to petroleum production;

•	Processing - incorporation into a formulation, mixture, or reaction product - intermediate; and

•	Industrial use - non-incorporative activities - process aid.

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Upon further review, the emission source information provided in the NEI database indicated that the
majority of emissions within this industry are combustion sources (e.g., reciprocating engines), with a
limited number of emission sources related to storage tanks, amine processes, and unclassified units with
emission sources typically less than 100 kg/year. These releases are lower than the median for the
industry sector, which have cancer risks below the 1 x 10~5. Therefore, EPA did not include the oil and
gas drilling, extraction, and support activities industry sector as the primary emissions are outside of the
scope of this draft risk evaluation.

Overall, these results indicate that while releases, exposures, and associated risk estimates may vary
across industry sectors and TSCA COUs, the results presented in Figure 4-11 are generally
representative of risks to individuals residing near industrial facilities releasing formaldehyde into the
ambient air that are associated with TSCA COUs.

Risks estimates calculated by the HEM model at census blocks were also considered to inform EPA's
understanding of how modeled results intersected with populated areas and demographic characteristics.
Overall, HEM modeling estimated a total population of 1,023,773 people experiencing a lifetime cancer
risk of at least one in one million. These cancer risk estimates are based solely on formaldehyde
emissions from facilities reporting to TRI, and do represent the aggregation of exposures from multiple
nearby facilities. A full breakdown of estimated population by level of risk estimate with stratification
by demographics is presented in Table 4-2. At higher levels of estimated risk, 6,935 people were
estimated to experience risk greater than 10 in 1 million, and 19 were estimated to experience risk
greater than 100 in 1 million. No estimated risks exceeded 200 in 1 million. Across the entire modeling
domain, which included census blocks within 50 km of any TRI facility reporting formaldehyde
releases, the average risk to the entire population of 232,907,302 people was estimated to be 0.04 in 1
million. This average risk was slightly higher for the African American and Native American
demographics included in the modeling, at an estimate of 0.06 in 1 million. While population counts are
summarized at the census block level, the demographic information is summarized by census block
group, and applied to each block within the block group. In order to avoid double counting, the
"Hispanic or Latino" category is treated as a distinct demographic category for these analyses. A person
is identified as one of five racial/ethnic categories presented below: White, African American, Native
American, Other and Multiracial, or Hispanic/Latino.

Table 4-2: Population Summary for Cancer Risk Estimates Derived from HEM Modeling of TRI
Releases Formaldehyde to Air	

Range of Lifetime
Individual Cancer
Risk

Number of People within 50 km of any Facility in Different Ranges for Lifetime

Cancer Risk

Total
Population

White

African
American

Native
American

Other and
Multiracial

Hispanic or
Latino

< 1 in 1 million

232,907,302

140,083,682

30,322,675

881,180

21,243,988

40,375,778

1 to <5 in 1 million

1,023,773

665,609

171,444

7,929

54,384

124,408

5 to <10 in 1
million

40,652

26,742

5,429

542

2,884

5,055

10 to <20 in 1
million

6,935

4,430

1,057

21

246

1,181

20 to <30 in 1
million

2,692

1,901

388

8

64

331

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Range of Lifetime
Individual Cancer
Risk

Number of People within 50 km of any Facility in Different Ranges for Lifetime

Cancer Risk

Total
Population

White

African
American

Native
American

Other and
Multiracial

Hispanic or
Latino

30 to <40 in 1
million

509

359

70

4

11

65

40 to <50 in 1
million

555

379

117

0

18

41

50 to <100 in 1
million

338

202

101

0

7

27

100 to <200 in 1
million

19

10

6

0

1

2

>200 in 1 million

0

0

0

0

0

0

Total population
within model
domain

233,982,775

140,783,315

30,501,287

889,684

21,301,603

40,506,886

Average risk
(chance in 1
million)

0.04

0.04

0.06

0.06

0.03

0.03

Further breakdown of relative population demographics compared to national averages is presented in
Table 4-3. This summary of results shows that among the population with estimated cancer risk modeled
by HEM to be higher than 1 in 1 million, some population groups are disproportionately represented,
which would be indicated by a higher percentage of a population group experiencing elevated risk than
the overall nationwide percentage of the population representing that group. These groups include white,
African American, and Native American demographics, as well as those with income below the poverty
level and those aged over 25 years without a high school diploma.

Table 4-3. Demographic Details of Population with Estimated Cancer Risk Higher than or Equal
to 1 in 1 Million, Compared with National Proportions	

Demographic

Nationwide

Population with Cancer Risk Higher than or Equal to 1 in
1 Million (Estimated by HEM Modeling of TRI Releases)

Total Population

329,824,950

1,075,473

Race and ethnicity In percent

White

59.5%

65.1%

African American

12.1%

16.6%

Native American

0.6%

0.8%

Other and Multiracial

8.8%

5.4%

Hispanic or Latino

19.0%

12.2%

Income In percent

Below Poverty l.c\cl

12 8%

15.7%

Above Poverty Level

87.2%

84.3%

Below Twice Poverty

30.2%

34.9%

Level





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Above Twice Poverty

69.8%

65.1%

Level





Lducalion In percent

Over 25 and without a

11.6%

12.3%

High School Diploma





Over 25 and with a

88.4%

87.7%

High School Diploma







1 .in<-

iiislically isolated In pcivcnl

Linguistically Isolated

5.2%

2.2%

Overall confidence in risk estimates based on modeled air concentrations is high for non-cancer risk
estimates and medium for cancer risk estimates. As described in Section 2.4.2, overall confidence in
modeling for exposures used to derive risk estimates for ambient air is high because modeling relies
upon direct reported releases from multiple years and databases that received a high-quality rating from
EPA's systematic review process. Peer-reviewed modeling approaches and methods with IIOAC were
used to estimate concentrations to derive risk estimates at distances from releasing facilities where
individuals typically reside for many years. Use of additional peer-reviewed models (AirToxScreen and
HEM) along with monitoring data (AMTIC) to further contextualize ambient air concentrations of
formaldehyde, which also present a consistent picture of exposures when compared to IIOAC results,
provide added strength and confidence to the risk estimates.

As described in Section 3.2, overall confidence in the acute and chronic, non-cancer hazard POD is high
while overall confidence in the inhalation unit risk for formaldehyde is medium. The cancer risk
estimates presented here do not include risks for some of the tumor sites. While the draft IRIS
assessment concluded that the evidence demonstrates that formaldehyde inhalation causes myeloid
leukemia and sinonasal cancer in humans, EPA was not able to quantify those risks with confidence.
The draft IRIS assessment estimated that the IUR used to estimate lifetime cancer risks may
underestimate total cancer risk by as much as 4-fold.

4.2.4.3 Integration of Modeling and Monitoring Information

EPA evaluated and characterized exposures and risks to the general population from industrial releases
of formaldehyde to the ambient air using actual reported releases and peer reviewed models to estimate
exposures at select distances from releasing facilities. EPA also evaluated and characterized exposures
and risks to the general population based on ambient monitoring data obtained from AMTIC.

Modeling and monitoring results show comparable exposures and risks to the general population from
formaldehyde in the ambient air. However, direct comparisons between modeled and monitored
concentrations and associated risks should be made with caution because each approach represents
different contributions to the overall exposures and associated risks.

EPA's modeling approaches use actual reported releases of formaldehyde, required to be reported by
statute to peer-reviewed databases, as direct inputs to peer-reviewed models. The models are then used
to estimate exposures used to derive risk estimates and characterize risks. Because the modeling
approaches use actual reported releases from real facilities, each release can be mapped to a
representative TSCA COU. This allows EPA to estimate exposures, derive risk estimates, and
characterize risks to its TSCA COU as required by statute and is a strength of the modeling approaches
used. However, since some modeling inputs require assumptions that may be conservative in nature and
retain some uncertainty results from modeling may overestimate exposures to the chemical modeled and
thus overestimate risk. While this may be seen as a limitation to the relevance of modeling to estimate

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exposures and associated risks, the modeling approaches are not overly conservative (based on a series
of sensitivity analyses) and provide a more health protective estimate for use in risk characterization,
risk determination, and regulatory decisions.

In addition to modeled concentrations of formaldehyde in ambient air, EPA relied upon monitoring data
from EPA's ambient air monitoring network. The monitoring network samples on a regular, and
sometimes continuous, basis concentrations of a variety of chemicals in the ambient air. The monitoring,
sampling, and analysis methods follow EPA reference methods, which have been rigorously peer
reviewed and often promulgated in the Code of Federal Regulations (CFR). Monitored concentrations,
therefore, represent actual measured concentrations of chemicals in the ambient air that contrasts with
modeled concentrations that are estimated based on a series of assumptions and input parameters.
However, ambient monitoring also measures the total concentration of the chemical in the ambient air,
which can be due to multiple sources (TSCA COUs, secondary formation, biogenic formation, and other
sources that cannot readily be mapped to a single TSCA COU). Since monitored concentrations
represent a total concentration of a chemical in ambient air, in a given location, at a given period in time,
monitoring data may be more representative of a total aggregate exposure of the general population to
formaldehyde in the ambient air rather than an independent exposure from a single source over a
continuous exposure period.

4.2.4.4 Overall Confidence in Exposures, Risk Estimates, and Risk Characterizations
for Ambient Air

Confidence in the characterization of exposures for the general population utilized to derive these risk
estimates is high as exposures are based on actual reported releases required by statute to be reported by
industry to peer-reviewed databases. Additionally, peer-reviewed models are used to model ambient air
concentrations at distances from releasing facilities where individuals within the general population
typically reside for many years. Finally, the TRI database undergoes repeatable quality assurance and
quality control reviews and is a high-quality database under EPA's systematic review process.

For formaldehyde, the potential contribution of combustion sources is an uncertainty and use of the full
facility data complicate singular TSCA COU estimates, such that emissions at one site may include
multiple sources under multiple COUs that include combustion sources and non-combustion sources.
For industrial COUs, EPA has a moderate to robust weight of scientific evidence as the databases have
high data quality scores and are supported by numerous data points. EPA targeted its assessment to
industrial COUs as it expects industrial releases to be the largest proportion of TSCA-related releases.
For commercial COUs, EPA used TRI and NEI results to inform the potential ranges of ambient air risk
estimates in Appendix D. EPA has a moderate weight of scientific evidence for the commercial COUs.

Overall confidence in risk estimates based on air concentrations modeled near release sites is high for
non-cancer estimates and moderate for cancer estimates based on the hazard values. As described in
Section 3.2, overall confidence in the chronic, non-cancer hazard POD is high, while overall confidence
in the inhalation unit risk for formaldehyde is medium. The cancer risk estimates presented here do not
include risks for some of the tumor sites. Although the draft IRIS assessment concluded that the
evidence demonstrates that formaldehyde inhalation causes myeloid leukemia and sinonasal cancer in
humans, EPA was not able to quantify those risks with confidence. The draft IRIS assessment estimated
that the IUR used to estimate lifetime cancer risks may underestimate total cancer risk by as much as 4-
fold.

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4.2.5 Comparison of Non-cancer Effect Levels and Air Concentrations

Hazard and risk assessments often lack human data on the specific concentrations at which an effect
occurs in people and risk estimates often incorporate a substantial amount of uncertainty. In the case of
formaldehyde, a robust database of epidemiology studies provides information about the air
concentrations of formaldehyde that have been associated with respiratory effects in people and supports
hazard values with minimal uncertainty.

Figure 4-12 indicates that the respiratory effects of formaldehyde in people can occur within the range of
air concentrations reported in monitoring studies. This comparison suggests that chronic exposure to
some of the indoor and outdoor air concentrations captured in available monitoring data are at levels that
may be expected to result in adverse health effects based on available human evidence.

ra
n>
Q

O)

Typical indoor air monitoring
(American Healthy Homes Survey)

Outdoor air monitoring (AMTIC)

Peak expiratory flow rate
Krzyzanowski et al., 1990

Rhinoconjunctivitis prevalence (children)
Annesi-Maesana et al., 2012

a> Asthma control (children with asthma)
§-	Venn etal., 2003

o

0. "	

- Current asthma prevalence (children)
¦§	Annesi-Maesano et al., 2012

UJ

Current asthma prevalence (children)
o	Krzyzanowski et al., 1990

2 	

o.

$ Eye irritation symptoms (residential)
^	Hanrahan et al., 1984

Eye irritation symptoms (healthy adults)
Kulleetal., 1987

Eye irritation symptoms (healthy adults)
Andersen, 1983

o«

~ I

O ~!

~

~I

—i	1—i—r—n

o

~	Air concentration range
o Air concentration median
¦ LOAEL

• BMC (5-10% change)
oPOD based on BMCL

~	POD based on NOAEL

Composite Uncertainty
Factor

o

o

-I—I I I I 11

1	10	100

Formaldehyde Concentration (pg/m3)

1000

Figure 4-12. Comparison of Non-cancer Health Effect Levels Reported in People and Indoor and
Outdoor Air Concentrations

Indoor air monitoring data summarized here are the American Healthy Homes Survey II data described in Section
2.3.1 and reflect the range of typical indoor air concentrations. Outdoor air monitoring data summarized here are
the AMTIC dataset and include a diverse range of outdoor air monitoring sources. Black shapes indicate air
concentrations at which adverse health effects were reported in epidemiology studies or controlled human
exposure studies (LOAEL or BMC), grey circles and squares indicate concentrations at which no significant
health effects were reported (NOAEL or BMCL), and grey bars indicate the total uncertainty factors identified for
each study. Effect levels (LOAEL, BMC, NOAEL and BMCL) and composite uncertainty factors for each study
are presented as reported in the draft IRIS assessment.

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4.2.6 Potentially Exposed or Susceptible Subpopulations

EPA considered PESS throughout the exposure and hazard assessments supporting this analysis. Table
4-4 summarizes how PESS were incorporated into the risk evaluation through consideration of increased
exposures and/or increased biological susceptibility. The table also summarizes the remaining sources of
uncertainty related to consideration of PESS. Appendix C provides additional details on PESS
considerations for the formaldehyde risk evaluation.

The available data suggest that some groups or lifestages have greater exposure to formaldehyde. For
example, people exposed to formaldehyde at work, those who frequently use consumer products
containing high concentrations of formaldehyde, people living or working near facilities that emit
formaldehyde, and people living in mobile homes and other indoor environments with high
formaldehyde concentrations are expected to have greater exposures. In this assessment, EPA evaluated
risks anticipated for a range of scenarios under TSCA COUs where exposures are expected to be
greatest. In addition to high exposures associated with COUs, some people will have greater exposure to
formaldehyde through sources that are not being assessed under TSCA. For example, those living near
major roadways, people living in areas with frequent exposure to wildfire smoke, smokers, and people
exposed to second-hand smoke, are expected to have greater exposures to formaldehyde. For these
groups, higher exposures from other sources of formaldehyde may increase susceptibility to additional
exposures from TSCA sources. As described in Section 4.3, EPA assessed risks from several aggregate
exposure scenarios; however, the wide range of possible combinations of aggregate sources are expected
to be highly variable across individuals and are a remaining source of uncertainty.

Some groups or lifestages may be more susceptible to the health effects of formaldehyde exposures. For
example, children have developing respiratory systems and narrower airways that may make them more
susceptible to the respiratory effects of formaldehyde. The chronic inhalation hazard value is derived in
part based on dose-response information in children with asthma and is supported by dose-response
information on lifestage-specific reproductive and developmental effects in humans and animals. The
chronic inhalation hazard value incorporates information on several sensitive groups; therefore, EPA
used a value of 3 for the UFh to account for human variability.

Other factors that may increase susceptibility to formaldehyde include chronic disease, co-exposures,
sex, lifestyle, sociodemographic status, and genetic factors. People with chronic respiratory diseases
(e.g., asthma) may be more susceptible to the respiratory effects of formaldehyde. Co-exposure to other
chemical or non-chemical stressors that increase risk of asthma, reduced pulmonary function,
reproductive and/or developmental toxicity, nasopharyngeal cancer or myeloid leukemia, may increase
susceptibility to the effects of formaldehyde on the same health outcomes. While these factors are not
quantitatively accounted for in the hazard characterization, EPA used values of 3 or 10 for the human
variability UFh to account for increased susceptibility when quantifying risks from exposure to
formaldehyde. The Risk Assessment Forum, in A Review of the Reference Dose and Reference
Concentration Processes (U.S. EPA. 2002). discusses some of the evidence for choosing the default
factor of 10 when data are lacking—including toxicokinetic and toxicodynamic factors as well as greater
susceptibility of children and elderly populations. U.S. EPA. (2002). however, did not discuss many of
the factors presented in Appendix CError! Reference source not found.

As described in Section 4.1.2 and in the draft IRIS assessment (	22b). EPA concluded that a

mutagenic mode of action is operative in formaldehyde-induced nasopharyngeal carcinogenicity. EPA
therefore applied ADAFs to lifetime cancer risk estimates to account for increased susceptibility to
nasopharyngeal cancer following inhalation exposure during early life.

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2732 Table 4-4. Summary of PESS Considerations Incorporated throughout the Analysis and Remaining Sources of Uncertainty

PESS
Categories

Potential Exposures Identified and
Incorporated into Exposure Assessment

Potential Sources of Biological Susceptibility Identified and
Incorporated into Hazard Assessment

Lifestage

EPA considered several scenarios in which lifestage may
influence exposure. For air exposures, the impacts of
lifestage differences were not able to be adequately
quantified and so the air concentrations are used for all
lifestages. Consumer exposure scenarios include lifestage-
specific exposure factors for adults, children, and formula-
fed infants (U.S. EPA, 2024d). Based on phvsical chemical
properties and a lack of studies evaluating potential for
accumulation in human milk following inhalation, dermal
or oral exposures, EPA did not quantitatively evaluate the
human milk pathway. This is a remaining source of
uncertainty. In the consumer exposure assessment, EPA
also considered potential oral exposure associated with
mouthing behaviors in infants and young children (U.S.
EPA. 2024d); however. EPA did not have sufficient
information on this exposure route to quantify risks.

EPA identified potential sources of biological susceptibility to
formaldehyde due to lifestage differences and developmental toxicity
as described in the draft IRIS assessment, the hazard value for chronic
inhalation was informed in part by dose-response data on asthma in
children, male reproductive toxicity, female reproductive effects and
developmental toxicity and is expected to be protective of these
endpoints. A 3/ UF was applied for human variability.

For oral, dermal, and acute inhalation hazard values, EPA did not
identify quantitative information on lifestage differences in toxicity and
this is a remaining source of uncertainty. A 10* UF was applied for
human variability.

EPA has concluded that a mutagenic mode of action is operative in
formaldehyde-induced nasopharyngeal carcinogenicity. To account for
increased cancer risks from early life inhalation exposures to
formaldehyde, EPA applied an age dependent adjustment factor
(ADAF) to cancer risk estimates to account for increased susceptibility
to nasopharyngeal cancer following exposure during early life.

Pre-existing
Disease

EPA did not identify health conditions that may influence
exposure. The potential for pre-existing disease to
influence exposure (due to altered metabolism, behaviors,
or treatments related to the condition) is a source of
uncertainty.

EPA identified the potential for pre-existing health conditions, such as
asthma, allergies, nasal damage, or other respiratory conditions to
contribute to susceptibility to formaldhyde. As described in the draft
IRIS assessment, EPA considered quantitative dose-response
information in children with asthma in derivation of the chronic
inhalation hazard value. A 3/ UF was applied for human variability.

For oral, dermal, and acute inhalation hazard values, the potential
influence of pre-existing diseases on susceptibility to formaldehyde
remains a source of uncertainty. A 10* UF was applied for human
variability.

Lifestyle
Activities

EPA identified smoking as an additional other source of
exposure to formaldehyde that may increase aggregate
exposure for smokers and people exposed to second-hand
smoke. To some degree, formaldehyde exposure from

EPA qualitatively described the potential for biological susceptibility
resulting from smoking, alcohol consumption and physical activity but
did not identify quantitative evidence of increased susceptibility to
formaldehyde. This is a remaining source of uncertainty.

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PESS
Categories

Potential Exposures Identified and
Incorporated into Exposure Assessment

Potential Sources of Biological Susceptibility Identified and
Incorporated into Hazard Assessment



smoking is indirectly accounted for in some indoor air
monitoring data described in Section 4.2.3.1, but it is not
directly quantified.



Occupational
Exposures

EPA evaluated risks for a range of occupational exposure
scenarios that increase exposure to formaldehyde,
including manufacturing, processing, and use of
formulations containing formaldehyde. EPA evaluated
risks for central tendency and high-end exposure estimates
for each of these scenarios (Section 4.2.1). Firefighters are
an occupational group expected to have increased exposure
to formaldehyde associated with combustion and burning
building materials but those exposures are beyond the
scope of this assessment.

EPA did not identify occupational factors that increase biological
susceptibility to formaldehyde. This is a remaining source of
uncertainty.

Geographic
Factors

EPA evaluated risks to communities in proximity to sites
where formaldehyde is released to ambient air (Section
4.2.4). In the environmental release assessment, EPA
mapped tribal lands in relation to air, surface water and
ground water releases of formaldehyde to identify potential
for increased exposures for tribes due to geographic
proximitv (U.S. EPA, 2024g). EPA also identified living
near major roadways or in areas with frequent exposure to
wildfire smoke as potential sources of increased exposure
to formaldehyde for some populations. These other sources
of exposure are a source of uncertainty that is not directly
incorporated into risk estimates for outdoor air exposures.

EPA did not identify geographic factors that increase biological
susceptibility to formaldehyde. This is a remaining source of
uncertainty.

Socio-

demographic
Factors

EPA did not identify specific sociodemographic factors
that influence exposure to formaldehyde. Income and other
sociodemographic factors may be correlated with some of
the exposure scenarios that result in greater exposure from
both TSCA and other sources (e.g., living near industrial
release sites, or near roadways). This is a remaining source
of uncertainty.

EPA qualitatively described the potential for biological susceptibility
due to socioeconomic factors, such as race or ethnicity and sex or
gender, but did not identify quantitative evidence of increased
susceptibility to formaldehyde. This is a remaining source of
uncertainty.

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PESS
Categories

Potential Exposures Identified and
Incorporated into Exposure Assessment

Potential Sources of Biological Susceptibility Identified and
Incorporated into Hazard Assessment

Nutrition

EPA did not identify nutritional factors influencing
exposure to formaldehyde. This is a remaining source of
uncertainty.

EPA did not identify nutritional factors that affect biological
susceptibility to formaldehyde.

Genetics

EPA did not identify genetic factors influencing exposure
to formaldehyde. This is a remaining source of uncertainty.

EPA qualitatively described the potential for biological susceptibility
due to genetic variants, which was accounted for applying a 10 x UF for
human variability. The specific magnitude of the impact of genetic
variants is unknown and remains a source of uncertainty.

Unique
Activities

EPA did not identify specific exposure scenarios that are
unique to tribes or other groups that expected to increase
exposure to formaldehyde. Potential sources of increased
exposure to formaldehyde due to specific tribal lifeways or
other unique activity patterns are a source of uncertainty.

EPA did not identify unique activities that influence susceptibility to
formaldehyde. This is a remaining source of uncertainty.

Aggregate
Exposures

EPA evaluated risk from multiple sources releasing to
indoor or outdoor air and aggregate exposures across
multiple exposure pathways or exposure scenarios. While
EPA assessed risks from several aggregate exposure
scenarios, the wide range of possible combinations of
aggregate sources are expected to be highly variable across
individuals and are a remaining source of uncertainty.

EPA does not identify ways that aggregate exposures would influence
susceptibility to formaldehyde. This remains a source of uncertainty.

Other

Chemical and
Non-chemical
Stressors

EPA did not identify chemical and nonchemical stressors
influencing exposure to formaldehyde. This is a remaining
source of uncertainty.

EPA qualitatively described the potential for biological susceptibility
due to chemical or nonchemical factors such as chemical co exposures
but did not identify specific quantitative evidence regarding
susceptibility to formaldhyde based on chemical and non-chemical
stressors. This remains a source of uncertainty.

2733

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4.3 Aggregate and Sentinel Exposures

TSCA section 6(b)(4)(F)(ii) (15 USC 2605(b)(4)(F)(ii)) requires EPA, in conducting a risk evaluation,
to describe whether aggregate or sentinel exposures under the COUs were considered and the basis for
their consideration.

EPA considered how aggregate exposures to formaldehyde from multiple sources, across multiple
routes, across groups of people or across pathways may increase the overall risk for some people.

The relative contributions of each source of formaldehyde to overall exposure and risk varies across
individuals, locations, and scenarios. For example, in communities living near industrial facilities with
high releases, those point sources may be one of the greatest sources of exposure to formaldehyde in
outdoor air. For people living near roadways, formaldehyde emitted from vehicles as a combustion
byproduct may be a greater source of exposure. For people living in mobile homes or other indoor
environments with high formaldehyde concentrations, indoor air in their homes may be the greatest
source of exposure. Some people may be exposed to formaldehyde from multiple sources in indoor and
outdoor air and through work or use of consumer products. For example, some people living near release
sites may also be exposed at work and through high concentrations of formaldehyde in indoor air at
home. Although there are too many possible combinations of exposures to evaluate all iterations, EPA
considered a range of scenarios in which aggregate exposures within and across exposure pathways may
increase total exposure and risk.

EPA qualitatively considered aggregate exposures and risks across inhalation, oral, and/or dermal routes
of exposure. For formaldehyde, cancer risk is only quantified for inhalation exposures and therefore
cannot be quantitatively aggregated across multiple routes. Non-cancer risks for formaldehyde are
highly route-specific and each route-specific hazard value was based on effects that occur near the portal
of entry. Because the non-cancer effects are specific to the route of exposure, EPA concluded that the
non-cancer risks are not additive across routes. Similarly, because EPA determined that risks are not
additive across routes, EPA did not aggregate exposure and risk across pathways for which exposure
routes are not the same (e.g., EPA did not aggregate inhalation exposure through outdoor air with
dermal exposure associated through use of consumer products).

EPA considered the combined exposures that may result from multiple sources releasing formaldehyde
to air in a particular indoor or outdoor environment. Monitoring data for formaldehyde is the best
available indication of aggregate exposures that occur in indoor or outdoor air under a range of
conditions. As described in Section 4.2.3 and Section 4.2.4.1, EPA considers the range of risk estimates
based on monitoring data to provide an estimate of the range of risks from aggregate exposures in air.
However, risk estimates based on monitoring do not provide information about the relative contribution
of different sources. EPA therefore also evaluated aggregate risks based on modeled air concentrations
for multiple TSCA sources releasing formaldehyde to outdoor air (Section 4.2.4.2 and the Draft Ambient
Exposure Assessment for Formaldehyde (	24a)). The Agency considered aggregating air

concentrations estimated for plausible combinations of COUs expected to co-occur in specific indoor air
environments (e.g., combinations of products likely to be present in mobile homes, new homes, or
automobiles), but concluded that COU-specific modeled air concentrations are too uncertain to support a
quantitative aggregate analysis across multiple COUs.

EPA qualitatively considered the aggregate exposures individuals may experience from multiple
exposure scenarios. For example, individuals exposed to formaldehyde through work or through use of
consumer products are expected to also have exposure to formaldehyde through outdoor air and/or

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indoor air. However, EPA concluded that there is too much uncertainty in the individual analyses
underlying exposure and risks from individual pathways to support a quantitative aggregate analysis. For
example, given uncertainty around modeled indoor air concentrations resulting from individual
consumer COUs, EPA concluded that aggregation of exposures resulting from multiple sources would
compound uncertainty. Further aggregating those combined indoor air exposures and risks with a set of
occupational exposures and risks would further compound those uncertainties. EPA is currently seeking
peer review of the methods underlying individual components of this draft analysis with the aim of
increasing confidence in exposure and risk estimates for each individual pathway and welcomes input on
approaches to improving confidence in an aggregate analysis.

EPA defines sentinel exposure as "the exposure to a single chemical substance that represents the
plausible upper bound of exposure relative to all other exposures within a broad category of similar or
related exposures (40 CFR § 702.33)." In this draft risk evaluation, EPA considered sentinel exposures
by considering risks to populations who may have upper bound exposures, including workers and ONUs
who perform activities with higher exposure potential and communities in proximity to release sites.
EPA characterized high-end exposures in evaluating exposure using both monitoring data and modeling
approaches. Where statistical data are available, EPA typically uses the 95th percentile value of the
available dataset to characterize high-end exposure for a given TSCA COU.

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5 NEXT STEPS

EPA's TSCA existing chemical risk evaluations must determine whether a chemical substance does or
does not present unreasonable risk under its COUs. The unreasonable risk must be informed by science,
but the Agency, in making the finding of "presents unreasonable risk" also considers risk-related factors
as described in its risk evaluation framework rule. Risk-related factors beyond exceedance of
benchmarks include the toxicological endpoint under consideration, the reversibility of the health effect
being evaluated, exposure-related considerations (e.g., duration, magnitude, or frequency of exposure, or
the size of population exposed), and the confidence in the information used to inform the hazard and
exposure values. Specifically, while EPA will consider the standard risk benchmarks associated with
interpreting margins of exposure and cancer risks, EPA cannot solely rely on those risk values. The
Agency also will consider naturally occurring sources of formaldehyde (i.e., biogenic, combustion, and
secondary formation) and associated risk levels from, and consider contributions from all sources as part
of a pragmatic and holistic evaluation of formaldehyde hazard and exposure in making its unreasonable
risk determination. If an estimate of risk for a specific scenario exceeds the benchmarks, then the
decision of whether those risks are unreasonable is both case-by-case and context driven. In the case of
formaldehyde, EPA is taking the risk estimates of the human health risk assessment (HHRA) in
combination with a thoughtful consideration of other sources of formaldehyde, to interpret the risk
estimates in the context of an unreasonable risk determination.

With regards to the HHRA, associated technical modules, and supporting documents, and in accordance
with the 2017 risk evaluation framework rule, OPPT's draft risk evaluation will be reviewed by the
SACC in 2024. OPPT will also be soliciting comments from the public. OPPT will ask for input from
the SACC on a variety of scientific issues related to human health hazard, ecological hazard, fate,
exposure assessment including its assessment of background sources, and weight of scientific evidence.
Due to the magnitude of available scientific information on formaldehyde coupled with its complex
toxicology and exposure profiles, EPA acknowledges that the evaluation of formaldehyde hazard and
exposure is challenging. EPA is at a critical point in the development of the draft risk evaluation where
SACC and public input will be important. For example, OPPT will seek input on its use of inputs and
assumptions in the exposure assessments for consumer and indoor air scenarios, in part to understand
whether its approach may compound one conservative assumption upon another in a manner that leads
to unrealistic or un-addressable outcomes. Following the SACC and public comments, EPA will revise
the draft risk evaluation and issue a final evaluation that will include a determination of whether, under
its conditions of use, formaldehyde presents unreasonable risk to health and the environment.

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REFERENCES

Annesi-Maesano. I; Hulin. M 1 jvaud. F; Raherison. C; Kopferschmitt. C; de Blav. F; Charpin. 1 * \
Denis. C. (2012). Poor air quality in classrooms related to asthma and rhinitis in primary
schoolchildren of the French 6 Cities Study. Thorax 67: 682-688.

http://dx.doi.ore 10 I l'< ihoraxinl-2011 -200 '>,vl
Appelman. LM; Wouterseri k \ ujm \ i .til e. HE; Feron. VI. (1988). One-year inhalation toxicity
study of formaldehyde in male rats with a damaged or undamaged nasal mucosa. J Appl Toxicol
8: 85-90. http://dx.doM	2/iat.2550080204

Asian. H; Son gin \ « un>\ \ i i teen ¦>N * T. O; Yagmurca. M: Turgut. M: Sarsilmaz. M; Kaplan. S.
(2006). Effects of formaldehyde exposure on granule cell number and volume of dentate gyrus: a
histopathological and stereological study. Brain Res 1122: 191-200.
http://dx.doi.ore	.brainres.2006.09.005

AT SDR. (1999). Toxicological profile for formaldehyde [ATSDR Tox Profile], Atlanta, GA: U.S.
Department of Health and Human Services, Public Health Service.
http://www.atsdr.cdc.eov/toxprofiles/

Basketter. DA; Gilmour. NJ; Wrie	;rs. T; Bom an. A; Li den. C. (2003). Biocides:

Characterization of the allergenic hazard of methylisothiazolinone. J Toxicol Cutan Ocul Toxicol
22: 187-199. http://dx.dou	1 /CUS-120026299

Bate son. TF; Schwe (2008). Children's response to air pollutants [Review], J Toxicol Environ

Health A 71: 238-243. http://dx.doi.ore/10.1080/15287390' 234
Beane Freeman. LE; Blair. A; Lubin. JH; Stewart P \	Uoover. RN; Hauptmann. M. (2013).

Mortality from solid tumors among workers in formaldehyde industries: an update of the NCI
cohort. Am J Ind Med 56: 1015-1026. http://dx.doi.ore/10.1002/aiim.22214
Bover. I J; Heldreth. iVrefeld. I ivlsito 1 *\ Utll K \ i Lessen. CD; Liebler. DC; Marks. JG;
Shank. RC; Slaea. TJ; Snyder. PW; Anderse: (2013). Amended safety assessment of
formaldehyde and methylene glycol as used in cosmetics. Int J Toxicol 32: 5S-32S.
http://dx.doi.ore

C (2004). Report to the California Legislature: Environmental health conditions in California's
portable classrooms. Sacramento, CA: CalEPA.

https://ww2.arb.ca.eov/sites/default/files/classic/research/apr/reports/13006.pdf
CDC. (2020). CDC Health Topics A-Z: Healthy food environments: Improving access to healthier food.
Available online at https://www.cdc.gov/nutrition/healthy-food-environments/improving-access-
to-healthier-food.html
CDC. (2021). CDC Health Topics A-Z: Micronutrients. Available online at
http s ://www. cdc. gov/nutriti on/m i cronutri ent-

m alnutrition/in dex.html'? C DC	ittps%3 A%2F%2Fwww.cdc. eov%2Fimmpact%2Fin

dex.html

CDC. (2022). CDC Health Topics A-Z: Physical activity. Available online at

https://www.cdc.eov/physicalactivity/index.html
CDC. (2023a). CDC Health Topics A-Z: Cancer. Available online at https://www.cdc.eov/cancer/
CDC. (2023b). CDC Health Topics A-Z: Infertility FAQs. Available online at

https://www.cdc.eov/reproductivehealth/infertility/index.htm
CDC. (2023c). CDC Health Topics A-Z: Nutrition. Available online at

http s ://www. cdc. eov/nutriti on/in dex. htm 1
CDC. (2023d). CDC Health Topics A-Z: Stress at work. Available online at

https://www.cdc.eov/niosh/topics/stress/

Ceballos. DM; Burr. GA. (2012). Evaluating a persistent nuisance odor in an office building. J Occup
Environ Hyg 9: D1-D6. http://dx.doi.oiv 10 IQSQ/1545962- i	l l

Page 114 of 151


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2921

2922

2923

2924

2925

2926

2927

2928

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PUBLIC RELEASE - DO NOT CITE OR QUOTE
March 2024

Civo Institute TNO. (1987). Chronic (2-year) oral toxicity and carcinogenicity study with formaldehyde
in rats, including interim kills after 12 and 18 months (final report) [TSCA Submission], In
Chronic oral toxicity and carcinogenicity study with formaldehyde in rats, pharmacokinetics and
metabolism of ingested and inhaled formaldehyde with cover letter dated 041988.
(v87.422/241112. OTS0000612-0. FYI-OTS-0588-0612. TSCATS/303710). Hoechst Celanese.
Delm;i;ir ,11Hokker Ut Bv^ X\ .n En gel en. JG. (2013). First tier modeling of consumer

dermal exposure to substances in consumer articles under REACH: A quantitative evaluation of
the ECETOC TRA for consumers tool. Regul Toxicol Pharmacol 65: 79-86.
http://dx.doi.ore/10.1016/i .yrtph.20 i J 10 01 ^

Delto	io. MH; Duester. G. (1999). Metabolic deficiencies in alcohol dehydrogenase Adhl,

Adh3, and Adh4 null mutant mice. Overlapping roles of Adhl and Adh4 in ethanol clearance
and metabolism of retinol to retinoic acid. J Biol Chem 274: 16796-16801.
http://dx.doi.ore	bc.274.24.16796

Dingier. FA; Wang. M; Mn \ \ Ellington. CL; Oberbeck. N: Watch am. S: Pontd < <' U jmimae-
Lanning. AN; Langevin t 'x adler. C; Cordell. RL; Monks. PS; Yu. R; Wilson. NK; Him \
Yoshida. K; Mori. M; Okamoto. Y; Okuno. Y; Muramatsu. H; Shiraishi. Y; Kobavashi. M;
Moriguchi. T; Osumi. T; Kato. M; Miyano. S; Ito. E; Kojima. S; Yabe. H; Yabe. M; Matsuo. K;
Ogawa. S; Gottgen; >dskinson. MRG; Takata. M; Patel. KJ. (2020). Two aldehyde
clearance systems are essential to prevent lethal formaldehyde accumulation in mice and
humans. Mol Cell 80: 996-1012.elO 19. http://dx.doi.org/10.1016/i.molcel.20J0 10 01 J
Dodson. KJ', [Souseman T \, 1 cv s. JL Spengler. ID; Shine. IP; Bennett. DH. (2007). Measured and

modeled personal exposures to and risks from volatile organic compounds. Environ Sci Technol
41: 8498-8505. http://dx.doi.org/10.1021/esC
ECHA. (2019). Annex XV restriction report, proposal for a restriction: Formaldehyde and formaldehyde
releasers. Helsinki, Finland: European Union, European Chemicals Agency.
https://echa.eiiropa.eii/documents/	formaldehyde axvreport en.pdf/2c798a08-

! 19-8180~a3c5a0362e37
Falk. IE; Into. IE; Stridii ^ r%v\ lin (1994). Dose-response study of formaldehyde on nasal mucosa
swelling. A study on residents with nasal distress at home. Am J Rhinol Allergy 8: 143-146.
http://dx.doi.org/10.2500/105Q65894'

Fishbein. L. (1992). Exposure from occupational versus other sources [Review], Scand J Work Environ
Health 18: 5-16.

Flyvholm. MA; Halt V ner. T; Tiedemann. E; Greenhill. P; Vanderveken. \\ . Heches H

Menne. T. (1997). Threshold for occluded formaldehyde patch test in formaldehyde-sensitive
patients. Relationship to repeated open application test with a product containing formaldehyde
releaser. Contact Derm 36: 26-33. http://dx.doi.oi^ 10 I I I I i I 00 0^'< rs° ib00918.x
Gilbert. NL; Gauvir* < * nay. M; Heroux. ME; Dupuis G, ] cgris. M; Chan. CC; Dietz. RN; Levesque.
(2006). Housing characteristics and indoor concentrations of nitrogen dioxide and
formaldehyde in Quebec City, Canada. Environ Res 102: 1-8.
http://dx.doi.ore	.envres.2006.02.007

Gilbert. NL; Guay. M; David Milln < > udek c. 1 ban. CC; Dales. RE. (2005). Levels and determinants
of formaldehyde, acetaldehyde, and acrolein in residential indoor air in Prince Edward Island,
Canada. Environ Res 99: 11-17. http://dx.doi.oo	¦envres.2004.09.009

Girroan. JR; Apte. IS I I > ay nor. GW; Allen, U< 160-4120(82)90030-7

Greet Sascom. R; Healey. EM; Hebel. JR; Sauder. LR; Kulle. TJ. (1989). Acute pulmonary

response in healthy, nonsmoking adults to inhalation of formaldehyde and carbon. J Toxicol
Environ Health 28: 261-275. http://dx.doi.org/10.1080/15287398909531347

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2972

2973

2974

2975

2976

PUBLIC RELEASE - DO NOT CITE OR QUOTE
March 2024

Green Oj Sander. LR; KiHb' I 1 ^' * scorn. R. (1987). Acute response to 3.0 ppm formaldehyde in
exercising healthy nonsmokers and asthmatics. Am Rev Respir Dis 135: 1261-1266.
http://dx.doi.org/10.1164/aixd.l987.135.6.1261
Harkev. M; Hotl	vim. El; Baker. KR; Henderson. B. (2021). Satellite Formaldehyde to Support

Model Evaluation. J Geophys Res Atmos 126. http://dx.doi.org/10.1029/2020JDQ32881
Hayes. RB; Blair. A; Stewan I U'rricl Kl Mahar. H. (1990). Mortality of U.S. embalmers and

funeral directors. Am J Ind Med 18: 641-652. http://dx.doi.ore/10.1002/aiim.4700180603
Hedberg. J J; Grafstrom M \ tmdracek. M; Sarang. Z; Wamam! 1 Ucog. JO. (2001). Micro-array
chip analysis of carbonyl-metabolising enzymes in normal, immortalised and malignant human
oral keratinocytes. Cell Mol Life Sci 58: 1719-1726. http://dx.doi.	L00000810

Herrero. M; Gonzalez. N: Rovira. J; Marques. M; Domingo. JL; Nadal. M. (2022). Early-life exposure

to formaldehyde through clothing. Toxics 10. http://dx.doi.org/10.3390/toxics 10070361
Hodgson. AT: Rude	. D; Chandra. S. (2000). Volatile organic compound concentrations and

emission rates in new manufactured and site-built houses. Indoor Air 10: 178-192.
http://dx.doi.org 10 1034/11600-0668.2000 01000 '< I
Hodgson. AT: Shendell. DG: Fisk	. MG. (2004). Comparison of predicted and derived

measures of volatile organic compounds inside four new relocatable classrooms. Indoor Air 14:
135-144. http://dx.doi.cnv 10 I I I I | I 00 0 i68._00 I 00 > I ^ \

Hohnloser. W: O-wjl.l K 1 mgens. F. (1980). ENZYMOLOGICAL ASPECTS OF CAFFEINE
DEMETHYLATION AND FORMALDEHYDE OXIDATION BY PSEUDOMONAS-
PUTIDA-C1. Hoppe Seylers Z Physiol Chem 361: 1763-1766.

K (1994). Human respiratory tract model for radiological protection. Ann ICRP 24.

IPCS. (2002). Concise International Chemical Assessment Document 40: Formaldehyde. Geneva,
Switzerland: World Health Organization.
https://inchem.org/documents/cicads/cicads/cicad40.htm
John. EM: Savitz. DA; Shy. CM. (1994). Spontaneous abortions among cosmetologists. Epidemiology

5: 147-155. http://dx.doi.org/10.1097/00001648-199403000-000Q4
Kerns. WD: Pavkov. KL; Pont *n lu > .ita. EJ; Swenbei^ (1983). Carcinogenicity of

formaldehyde in rats and mice after long-term inhalation exposure. Cancer Res 43: 4382-4392.
Kriebel. D; Sam .	anom «' (1993). Reversible pulmonary responses to formaldehyde. A study

of clinical anatomy students. Am Rev Respir Dis 148: 1509-1515.
http://dx.doi.org/10.1164/airccm I IS I I ^09
Krzyzanowski. M; Ouackenbo	jwitz. MP. (1990). Chronic respiratory effects of indoor

formaldehyde exposure. Environ Res 52: 117-125. http://dx.doi.org/10.1016/S0013-
i

Kulle l< v auder. LR: Hdvl K -kyii 0,1. Chatham. MO (1987). Formaldehyde dose-response in
healthy nonsmokers. J Air Pollut Control Assoc 37: 919-924.
http://dx.doi.orE 30/08940630.1987.10466285

1 r^'cknei i	li (2008). Formaldehyde and chemosensory irritation in humans: A

controlled human exposure study. Regul Toxicol Pharmacol 50: 23-36.

http://dx.doi.org 10 101 i.yrtph.200 OS.012
Lawn I 's < 1 tr \ I sel. CP. (1995). Exposure to volatile organic compounds in the passenger
compartment of automobiles during periods of normal and malfunctioning operation. J Expo
Anal Environ Epidemiol 5: 511-531.

Lawrvk. NJ: Weisel. CP. (1996). Concentrations of volatile organic compounds in the passenger
compartments of automobiles. Environ Sci Technol 30: 810-816.
http: //dx. doi. or g/10.1021 /e s95 0225n

Page 116 of 151


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3014

3015

3016

3017

3018

3019

3020

3021

3022

3023

PUBLIC RELEASE - DO NOT CITE OR QUOTE
March 2024

LBNL. (2008). Aldehyde and other volatile organic chemical emissions in four FEMA temporary
housing units - final report. (LBNL-254E). Berkley, CA.

https://www.cdc.eov/air/trailerstudy/pdfs/lbnl-254e.pdf
Liu. KS; Huang. R . Hayward. SB; Wesolowski. J; Sexton. K. (1991). Irritant effects of formaldehyde
exposure in mobile homes. Environ Health Perspect 94: 91-94.
http://dx.doi.org/10.23(	|

Liu. W: Zham < ham 1	r%< W ^Isel. CP: Morandi. MT; Stock. TH; Colome. S: Korn. LR.

(2006). Estimating contributions of indoor and outdoor sources to indoor carbonyl concentrations
in three urban areas of the United States. Atmos Environ 40: 2202-2214.
http://dx.doi.org/10 J 016/i .atmosenv...00 ^ I _ 00
Luecken.	ood. G; Hutzell. WT. (2019). Multi pollutant modeling of ozone, reactive nitrogen

and HAPs across the continental US with CMAQ-CB6. Atmos Environ 201: 62-72.
http://dx.doi.org 10 101 i.atmosenv.,0is II 0 >j0
Lukcso. D; Guidotti. TL; Franklin. DE; B (2014). Indoor Environmental and Air Quality

Characteristics, Building-Related Health Symptoms, and Worker Productivity in a Federal
Government Building Complex. Arch Environ Occup Health 71:0.
http://dx.doi.org 10 1080/19338244.2014.96 •*. I
Maronpot. RR; h idln I n \ 1 iarke. WJ; Westerb''^ M % ker. JR; Moss. OR. (1986). Toxicity of
formaldehyde vapor in B6C3F1 mice exposed for 13 weeks. Toxicology 41: 253-266.
http://dx.doi.org/ i 0. i 0 i 6/0300~483X(86)90180-0
Matsunaga. I; Miya	hida. T; Miyamoto. S; Ohya. Y; Sasaki. S; Tanaka. K; Oda. H; Ishiko. O;

Hirol	p. OMaCHS. (2008). Ambient formaldehyde levels and allergic disorders among

Japanese pregnant women: Baseline data from the Osaka maternal and child health study. Ann
Epidemiol 18: 78-84. http://dx.doi.Org/10J016/i.annepidem.200 0 0°^

Muellci JL, Hiuckner. I' I't >obig. G. (2013). Exposure study to examine chemosensory effects of

formaldehyde on hyposensitive and hypersensitive males. Int Arch Occup Environ Health 86:
107-117. http://dx.doi.oiy 10 100 ^ 00420 01.0 ^ ^

Murphy. MW; Lando. IF; Kieszak. SM; Sutter. ME; Noona	mkard. JM; McGeehin. MA.

(2013). Formaldehyde levels in FEMA-supplied travel trailers, park models, and mobile homes
in Louisiana and Mississippi. Indoor Air 23: 134-141. http://dx.doi.org/10.1 1 1 1 /] A 600-
0668.2012.00800.x

Nakamura J. Holley. DW; Kawamoto I < 'ultman. SI. (2020). The failure of two major formaldehyde
catabolism enzymes (ADH5 and ALDH2) leads to partial synthetic lethality in C57BL/6 mice.
Genes Environ 42: 21. http://dx.doi.o	'0-00160-4

NASEM. (2023). Review of EPA's 2022 Draft Formaldehyde Assessment. Washington, DC.

https://nap.nationalacademies.org/catalog/27i53/review-of-epas-2022-draft-formaldehyde-
assessment

ODPHP. (2023a). Healthy People 2030 - Social determinants of health literature summaries:
Neighborhood and built environment. Available online at

https://health.gov/healthvpeople/prioritv-areas/social-determinants-health/literature-
summaries#neighborhood
ODPHP. (2023b). Healthy People 2030 - Social determinants of health literature summaries: Poverty.
Available online at https://health.gov/healthypeople/priority-areas/social-determinants-
h ealth/literature-sum m aries/poverty
ODPHP. (2023c). Healthy People 2030 - Social determinants of health literature summaries: Social and
community context. Available online at https://health.gov/healthvpeople/prioritv-areas/social-
determ inants-h ealth/literature-sum m ari es#soci al

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Offermann. FJ; Robertson. J; Springes 'ennan. S; Woo. T. (2008). Window usage, ventilation, and
formaldehyde concentrations in new California homes: Summer field sessions. Paper presented at
ASHRAE IAQ 2007, Baltimore, MD.

Paee. E; Couch. J. (2014). Evaluation of employee health concern and suspected contamination at an
office complex. (Report No. 2010-0061-3206). Washington, DC: National Institute for
Occupational Safety and Health.

OuanTech. (2021). American Healthy Homes Survey, final report: Data documentation. (AHHSII).
Washington, DC: U.S. Department of Housing and Urban Development.
https://www.hud.eov/proeram offices/healthy homes
Riess 1 i ^'etbm ^ i aud t i uhrmann F, Markewitz. D; Salthammer. T. (2010). Experimental

setup and analytical methods for the non-invasive determination of volatile organic compounds,
formaldehyde and NOx in exhaled human breath. Anal Chim Acta 669: 53-62.
http://dx.doi.ore	.aca.2010.04.049

Salthammer. T. (2019). Formaldehyde sources, formaldehyde concentrations and air exchange rates in
European housings. Build Environ 150: 219-232.
http://dx.doi.ore 10 101 | .buildenv.2^1 \ - l _ « L
Satrtiaeo. LY; Hann. MC: Ben-Jebria. man. JS. (2001). Ozone absorption in the human nose
during unidirectional airflow. J Appl Physiol (1985) 91: 725-732.
http://dx.doi.ore/10 1152/iappl.2001.91.2.725
Sarsilmaz. M; Kaplan. S: Songur V C'olakoelu. S: Asian. H; Tunc \ f O	I'm gut. M; Ba <15

(2007). Effects of postnatal formaldehyde exposure on pyramidal cell number, volume of cell
layer in hippocampus and hemisphere in the rat: A stereological study. Brain Res 11: 157-167.
http://dx.doi.ore 10 101 i.brainres.200 01 I
Si(X v ^ rennet! DK. Cliillrud. SN: Kinney. PL; Spengler M * (2004). Differences in source emission
rates of volatile organic compounds in inner-city residences of New York City and Los Angeles.
J Expo Anal Environ Epidemiol 14: S95-S109. http://dx.doi.ore/10.1038/si.iea.7500364
Scheie¦ KH 'Maim. M; Phillips 1'luirman. J; Eyth. A; Fudge. S; Morris. U	i t <>ok. R.

(2016). Hybrid Modeling Approach to Estimate Exposures of Hazardous Air Pollutants (HAPs)
for the National Air Toxics Assessment (NATA). Environ Sci Technol 50: 12356-12364.
http://dx.doi.ore/10J02 l/acs.est.6b04752
Singh. I; Raizada. KM; Chaturvedi. VN; Jain. SK. (1998). Nasal mucous ciliary clearance and olfaction

in atrophic rhinitis. 50: 57-59. http://dx.doi.(	996772

Summers. RM; Louie. T; Yu. C; Gakl	ie. KC; Subramanian. M. (2012). Novel, Highly

Specific N-Demethylases Enable Bacteria To Live on Caffeine and Related Purine Alkaloids. J
Bacteriol 194: 2041-2049. http://dx.doi.oi v 10 I I. s }\ I 0> \ '« I I
Tan. T; Zhane \ . Luo. W; Lv. J; Han i Umili.n i )' 1 uo. H; Li. H; Wan. \ \ ring. X; Song. W;

Tone. Z. (2018). Formaldehyde induces diabetes-associated cognitive impairments. FASEB J 32:
3669-3679. http://dx.doi.ore/10.1096/fi.201701239R
Taskinen. HK; Kyyronen. P; Sallmen. M; Virtanen. S\ ,1 iukkoneii I'\ H.ui
  • 3.0.co;2-d Thompson. CM; Sonawane afStrom. RC. (2009). The ontogeny, distribution, and regulation of alcohol dehydrogenase 3: Implications for pulmonary physiology [Review], Drug Metab Dispos 37: 1565-1571. http://dx.doi.oi d. 109.027904 Til. HP; W outer sen. RA; Feron. VI; Clary. II. (1988). Evaluation of the oral toxicity of acetaldehyde and formaldehyde in a 4-week drinking-water study in rats. Food Chem Toxicol 26: 447-452. http://dx.doi.orE >278-6915(88)90056-7 Page 118 of 151

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    3116
    
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    3118
    
    3119
    
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    Til. HP; W outer sen. R.A.; Feron. VI; Hollanders. "VH ker. HE; Clary. II. (1989). Two-year
    drinking-water study of formaldehyde in rats. Food Chem Toxicol 27: 77-87.
    
    http://dx.doi.org/ i 0. i 0 i 6/0278-6915(89V\W I \
    
    IJ.S JitSl (2014). Employee Tenure News Release. Available online at
    
    http://www.bls.eov/news.release/archives/temire 0918^ m
    US Census Bureau. (2019a). Survey of Income and Program Participation data. Available online at
    
    https://www.census.eov/proerams-surveys/sipp/data/datasets/2008-panel/wave-l.html (accessed
    May 16, 2019).
    
    sus Bureau. (2019b). Survey of Income and Program Participation: SIPP introduction and
    history. Washington, DC. https://www.census.gov/programs-survevs/sipp/about/sipp-
    introducti on -history .html
    
    (1992). A laboratory method to determine the retention of liquids on the surface of hands
    [EPA Report], (EPA/747/R-92/003). Washington, DC.
    
    (2002). A review of the reference dose and reference concentration processes [EPA Report],
    (EPA630P02002F). Washington, DC. https://www.epa.gov/sites/production/files/2014-
    )cum ents/rfd-final.p df
    
    U.S. EPA. (2005a). Guidance on selecting age groups for monitoring and assessing childhood exposures
    to environmental contaminant (pp. ii-36). (EPA/630/P-03/003F). Washington, DC: Risk
    Assessment Forum, https://www.epa.gov/risk/guidance-selecting-age-groups-monitorine-and-
    assessing-childhood-exposures-environmental
    U.S. EPA. (2005b). Supplemental guidance for assessing susceptibility from early-life exposure to
    carcinogens [EPA Report], (EPA/630/R-03/003F). Washington, DC: U.S. Environmental
    Protection Agency, Risk Assessment Forum, https://www.epa.gov/risk/supplemental-guidance-
    assessine-susceptibility-early-life-exposure-carcinoeens
    U.S. EPA. (201 1). Exposure factors handbook: 201 1 edition [EPA Report], (EPA/600/R-090/052F).
    
    Washington, DC: U.S. Environmental Protection Agency, Office of Research and Development,
    National Center for Environmental Assessment.
    https://nepis.epa. eov/Exe/ZyPURL. cei?Dockev=P 100F2QS.txt
    U.S. EPA. (2013). Updating CEB's method for screening-level estimates of dermal exposure. Chemical
    Engineering Branch.
    
    (2016a). Chemical data reporting: 2016 data. Washington, DC: U.S. Environmental
    Protection Agency, Chemical Data Reporting. Retrieved from https://www.epa.eov/chemical-
    data-reportine/access-cdr-data#2016
    U.S. EPA. (2016b). Formaldehyde from composite wood products: Exposure assessment for TSCA. Title
    VI Final Rule. Washington, DC: Risk Assessment Division, Office of Pollution Prevention and
    Toxics, Office of Chemical Safety and Pollution Prevention.
    
    U.S. EPA. (2019). Consumer Exposure Model (CEM) 2.1 User Guide. (EPA Contract # EP-W-12-010).
    Washington, DC.
    
    (2020a). 2020 CDRData [Database], Washington, DC. Retrieved from
    
    https://www.epa.gOv/chemical-data-reporting/access-cdr-data#2020
    1 v M \ (2020b). 2020 CDR: Commercial and consumer use. Washington, DC.
    
    U.S. EPA. (2020c). 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-Q9/documents/casrn 50-00-0-
    formaldehyde fmalscope cor.pdf
    U.S. EPA. (2020d). Use Report for Formaldehyde (CASRN 50-00-0). Washington, DC: Office of
    
    Chemical Safety and Pollution Prevention. https://www.regulations.eov/document/EPA-HQ-
    OPPT-2018-043 8-0028
    
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    3163
    
    3164
    
    3165
    
    3166
    
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    U.S. EPA. (2021a). About the Exposure Factors Handbook. Available online at
    https://www.epa.gov/expobox/about-exposure-factors-handbook
    
    (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.reeiilations.eov/dociiment/EPA-HQ-OPPT-2'
    
    0005
    
    U.S. EPA. (2022a). Ambient Monitoring Technology Information Center (AMTIC) - Ambient
    Monitoring Archive for HAPs [Database], Washington, DC. Retrieved from
    
    https://www.epa.eov/amtic/amtic-ambient-monitorine-archive-haps
    U.S. EPA. (2022b). Toxicological Review of Formaldehyde—Inhalation (Review draft). Washington,
    DC: Integrated Risk Information System.
    
    https://cfpub.epa.eov/ncea/iris drafts/recordi spl ay. cfm ? dei d=248150
    U.S. EPA. (2023a). Draft Risk Evaluation for Formaldehyde - Systematic Review Protocol.
    
    Washington, DC: Office of Pollution Prevention and Toxics, Office of Chemical Safety and
    Pollution Prevention.
    
    U.S. EPA. (2023b). Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File:
    Data Extraction Information for Environmental Hazard and Human Health Hazard Animal
    Toxicology and Epidemiology. Washington, DC: Office of Pollution Prevention and Toxics,
    Office of Chemical Safety and Pollution Prevention.
    
    U.S. EPA. (2023c). Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File:
    Data Extraction Information for General Population, Consumer, and Environmental Exposure.
    Washington, DC: Office of Pollution Prevention and Toxics, Office of Chemical Safety and
    Pollution Prevention.
    
    U.S. EPA. (2023d). Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File:
    Data Quality Evaluation and Data Extraction Information for Environmental Fate and Transport.
    Washington, DC: Office of Pollution Prevention and Toxics, Office of Chemical Safety and
    Pollution Prevention.
    
    U.S. EPA. (2023e). Draft 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. (2023f). Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File:
    Data Quality Evaluation and Data Extraction Information for Physical and Chemical Properties.
    Washington, DC: Office of Pollution Prevention and Toxics, Office of Chemical Safety and
    Pollution Prevention.
    
    U.S. EPA. (2023g). Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File:
    Data Quality Evaluation Information for General Population, Consumer, and Environmental
    Exposure. Washington, DC: Office of Pollution Prevention and Toxics, Office of Chemical
    Safety and Pollution Prevention.
    
    U.S. EPA. (2023h). Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File:
    Data Quality Evaluation Information for Human Health Hazard Animal Toxicology.
    
    Washington, DC: Office of Pollution Prevention and Toxics, Office of Chemical Safety and
    Pollution Prevention.
    
    U.S. EPA. (2023i). Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File:
    
    Data Quality Evaluation Information for Human Health Hazard Epidemiology. Washington, DC:
    Office of Pollution Prevention and Toxics, Office of Chemical Safety and Pollution Prevention.
    
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    3214
    
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    U.S. EPA. (2023j). Draft Risk Evaluation for Formaldehyde: Systematic review supplemental file: Data
    quality evaluation information for environmental hazard. Washington, DC: Office of Pollution
    Prevention and Toxics, Office of Chemical Safety and Pollution Prevention.
    
    U.S. EPA. (2023 k). Summarized data of the Building Assessment Survey and Evaluation (BASE) Study.
    Available online at https://www.epa.gov/indoor-air-qualitv-iaq/summarized-data-building-
    assessment- survev-an d-evaluati on - study (accessed October 25, 2023).
    
    U.S. EPA. (2024a). Draft Ambient Air Exposure Assessment for the Formaldehyde Risk Evaluation.
    Washington, DC: U.S. Environmental Protection Agency, Office of Pollution Prevention and
    Toxics.
    
    U.S. EPA. (2024b). Draft Chemistry, Fate, and Transport Assessment for Formaldehyde. Washington,
    DC: U.S. Environmental Protection Agency, Office of Pollution Prevention and Toxics.
    
    (2024c). Draft Conditions of Use for the Formaldehyde Risk Evaluation. Washington, DC:
    U.S. Environmental Protection Agency, Office of Pollution Prevention and Toxics.
    
    (2024d). Draft Consumer Exposure Assessment for Formaldehyde. Washington, DC: U.S.
    Environmental Protection Agency, Office of Pollution Prevention and Toxics.
    
    (2024e). Draft Environmental Exposure Assessment for Formaldehyde. Washington, DC:
    U.S. Environmental Protection Agency, Office of Pollution Prevention and Toxics.
    
    (2024f). Draft Environmental Hazard Assessment of Formaldehyde. Washington, DC: U.S.
    Environmental Protection Agency, Office of Pollution Prevention and Toxics.
    
    (2024g). Draft Environmental Release Assessment for Formaldehyde. Washington, DC: U.S.
    Environmental Protection Agency, Office of Pollution Prevention and Toxics.
    
    (2024h). Draft Environmental Risk Assessment Characterization of Formaldehyde.
    Washington, DC: U.S. Environmental Protection Agency, Office of Pollution Prevention and
    Toxics.
    
    U.S. EPA. (2024i). Draft Human Health Hazard Assessment for Formaldehyde. Washington, DC: U.S.
    Environmental Protection Agency, Office of Pollution Prevention and Toxics.
    
    (2024j). Draft Indoor Air Exposure Assessment for Formaldehyde. Washington, DC: U.S.
    Environmental Protection Agency, Office of Pollution Prevention and Toxics.
    
    (2024k). Draft Occupational Exposure Assessment for Formaldehyde. Washington, DC: U.S.
    Environmental Protection Agency, Office of Pollution Prevention and Toxics.
    
    Venn	er. M; Antoniak. M; Laughlin. C; Britton. J: Lewis. SA. (2003). Effects of volatile
    
    organic compounds, damp, and other environmental exposures in the home on wheezing illness
    in children. Thorax 58: 955-960. http://dx.doi.org/10.1136/thorax.:
    
    Wang. H; Li. H. eC; Lv. M; Zhou. O, H;ii 1 I *u 1 \ue. X. ia: Lin I ^ » Ha. S. (2015). Associations
    between occupation exposure to Formaldehyde and semen quality, a primary study. Sci Rep 5:
    15874. http://dx.doi.on	>rep!5874
    
    Wang. P; Holtowav	tev. M; De Smedt. I. (2022). Ambient Formaldehyde over the
    
    United States from Ground-Based (AQS) and Satellite (OMI) Observations. Remote Sensing 14:
    2191. http://dx.doi.org/10.3390/rsl40
    Westat. (1987). Household solvent products: A national usage survey [EPA Report], (EPA-OTS 560/5-
    87-005). Washington, DC: Office of Toxic Substances, Office of Pesticides and Toxic
    Substances. https://nepis.epa.gov/Exe/ZvPURLj ckev=P 100754Q.txt
    W outer sen. RA; Appelman. LM; Wilmer. JWG. M; Fatke. HE; Feron. VI. (1987). Subchronic (13-
    week) inhalation toxicity study of formaldehyde in rats. J Appl Toxicol 7: 43-49.
    http://dx.doi.orE	at.2550070108
    
    W outer sen. RA; van Garderen-Hoetmer. A; Bruijnties. IP; Zwt	>n. VJ. (1989). Nasal tumours
    
    in rats after severe injury to the nasal mucosa and prolonged exposure to 10 ppm formaldehyde. J
    Appl Toxicol 9: 39-46. http://dx.doi.org/10.1002/iat.25500901Q8
    
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    Wu. H; Romieu. I; Seinra-Monge. J; del Rio-Na^	lerson. DM; Jenchura. CA; Li. H;
    
    Ramirez-Aguilar. M; Lara-Sanchez. I; London. SI. (2007). Genetic variation in S-
    nitrosoglutathione reductase (GSNOR) and childhood asthma. J Allergy Clin Immunol 120: 322-
    328. http://dx.doi.org/IO. i0 i6/i.iact.2007.04.022
    Zhu. L; Jacob. DJ; Keutsch. FN: Micl< 1 < v ;heffe. R: Strum. M: Gonzalez Abad. G: Chance. K:
    
    Yang. K: Rappengluck. B: Millet. DB: Baasandori. M: Jaes !-¦ 1 Shah. V. (2017). Formaldehyde
    (HCHO) as a hazardous air pollutant: Mapping surface air concentrations from satellite and
    inferring cancer risks in the United States. Environ Sci Technol 51: 5650-5657.
    http://dx.doi.org/10J02 l/acs.est.?b01356
    Zwart, A; W outer sen. RA: Wilmer. JWG. M: Sp	?n. VI. (1988). Cytotoxic and adaptive effects
    
    in rat nasal epithelium after 3-day and 13-week exposure to low concentrations of formaldehyde
    vapour. Toxicology 51: 87-99. http://dx.dou	5/0300~483X(88)90083~2
    
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    APPENDICES
    
    Appendix A ABBREVIATIONS AND ACRONYMS
    
    ACGM
    
    American Conference of Governmental Industrial Hygienists
    
    ADAF
    
    Age-dependent adjustment factor
    
    ADC
    
    Average daily concentrations
    
    BMD
    
    Benchmark dose
    
    BMR
    
    Benchmark response
    
    CASRN
    
    Chemical Abstracts Service Registry Number
    
    CDR
    
    Chemical Data Reporting
    
    CEHD
    
    Chemical Exposure Health Data
    
    CEM
    
    Consumer Exposure Model
    
    CERCLA
    
    Comprehensive Environmental Response, Compensation and Liability Act
    
    CFR
    
    Code of Federal Regulations
    
    CNS
    
    Central nervous system
    
    DIY
    
    Do it yourself
    
    DMR
    
    Discharge Monitoring Report
    
    EPA
    
    Environmental Protection Agency
    
    ESD
    
    Emission Scenario Document
    
    FSHA
    
    Federal Hazardous Substance Act
    
    GS
    
    Generic Scenario
    
    HAP
    
    Hazardous Air Pollutant
    
    HEC
    
    Human Equivalent Concentration
    
    HED
    
    Human Equivalent Dose
    
    HEM
    
    Human Exposure Module
    
    HERO
    
    Health and Environmental Research Online (Database)
    
    HUD
    
    (U.S.) Department of Housing and Urban Development
    
    IIOAC
    
    Integrated Indoor-Outdoor Air Calculator (Model)
    
    IRIS
    
    Integrated Risk Information System
    
    Koc
    
    Soil organic carbon: water partitioning coefficient
    
    Kow
    
    Octanol: water partition coefficient
    
    LADC
    
    Lifetime average daily concentrations
    
    LC50
    
    Lethal concentration at which 50% of test organisms die
    
    LD50
    
    Lethal dose at which 50% of test organisms die
    
    LOD
    
    Limit of detection
    
    Log Koc
    
    Logarithmic organic carbon: water partition coefficient
    
    Log Kow
    
    Logarithmic octanol: water partition coefficient
    
    MOA
    
    Mode of action
    
    NAICS
    
    North American Industry Classification System
    
    NASEM
    
    National Academies of Sciences, Engineering, and Medicine
    
    ND
    
    Non-detect
    
    NEI
    
    National Emissions Inventory
    
    NESHAP
    
    National Emission Standards for Hazardous Air Pollutants
    
    NIOSH
    
    National Institute for Occupational Safety and Health
    
    NPDES
    
    National Pollutant Discharge Elimination System
    
    OCSPP
    
    Office of Chemical Safety and Pollution Prevention
    
    OES
    
    Occupational exposure scenario
    
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    ONU
    
    Occupational non-user
    
    OPPT
    
    Office of Pollution Prevention and Toxics
    
    OSHA
    
    Occupational Safety and Health Administration
    
    PEL
    
    Permissible exposure limit
    
    PESS
    
    Potentially exposed or susceptible subpopulations
    
    POD
    
    Point of departure
    
    POTW
    
    Publicly owned treatment works
    
    PPE
    
    Personal protective equipment
    
    REL
    
    Recommended Exposure Limit
    
    SACC
    
    Science Advisory Committee on Chemicals
    
    SDS
    
    Safety data sheet
    
    STEL
    
    Short-Term Exposure Limit
    
    TLV
    
    Threshold Limit Value
    
    TRI
    
    Toxics Release Inventory
    
    TSCA
    
    Toxic Substances Control Act
    
    TTO
    
    Total toxic organics
    
    TWA
    
    Time-weighted average
    
    U.S.
    
    United States
    
    WWT
    
    Wastewater treatment
    
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    Appendix B LIST OF DOCUMENTS AND SUPPLEMENTAL FILES
    
    List of Documents and Corresponding Supplemental Files
    
    1.	Draft Conditions of Use for the Formaldehyde Risk Evaluation, (	,024c).
    
    2.	Draft Environmental Risk Assessment for Formaldehyde, (	2024h)
    
    3.	Draft Chemistry, Fate, and Transport Assessment for Formaldehyde, (U.S. EPA. 2024b).
    
    4.	Draft Environmental Release Assessment for Formaldehyde, (	2024g).
    
    4.1.	Supplemental Air Release Summary and Statistics for NEI and TRIfor Formaldehyde.xlsx
    
    4.2.	Supplemental Land Release Summary for TRIfor Formaldehyde.xlsx
    
    4.3.	Supplemental Water Release Summary for DMR and TRIfor Formaldehyde.xlsx
    
    5.	Draft of Environmental Exposure Assessment for Formaldehyde, (	)
    5.1. Supplemental Water Quality Portal Results for Formaldehyde.xlsx
    
    6.	Draft Environmental Hazard Assessment of Formaldehyde, (	324f)
    
    7.	Draft Occupational Exposure Assessment for Formaldehyde, (	2024k)
    
    7.1.	Draft Formaldehyde Occupational Exposure Modeling Parameter Summary.xlsx
    
    7.2.	Draft Occupational Supplemental Formaldehyde Risk Calculator.xlsx
    
    7.3.	Draft Supplemental Occupational Monitoring Data Summary.xlsx
    
    8.	Draft Consumer Exposure Assessment for Formaldehyde, (U.S. EPA. 2024d).
    
    8.1.	Draft Consumer Modeling, Supplemental A for Formaldehyde, xlsx
    
    8.2.	Draft Consumer Acute Dermal Risk Calculator, Supplemental B for Formaldehyde, xlsm
    
    8.3.	Draft Consumer - Indoor Air Acute and Chronic Inhalation Risk Calculator, Supplemental B
    for Formaldehyde.xlsm
    
    9.	Draft Indoor Air Exposure Assessment for Formaldehyde, (	24i).
    
    9.1.	Draft Indoor Air Modeling, Supplemental A for Formaldehyde, xlsx
    
    9.2.	Draft Consumer - Indoor Air Acute and Chronic Inhalation Risk Calculator, Supplemental B
    for Formaldehyde.xlsm
    
    10.	Draft Ambient Air Exposure Assessment for Formaldehyde, (U.S. EPA. 2024a)
    
    10.1.	Draft IIOAC Assessment Results and Risk Calcs Supplement A for Ambient Air. xlsx
    
    10.2.	Draft IIO AC Assessment Results and Risk Calcs for Formaldehyde Supplement B.xlsx
    
    1 1. Draft Human Health Hazard Assessment for Formaldehyde, (	024i).
    
    12. Draft Risk Evaluation for Formaldehyde - Systematic Review Protocol (U.S. EPA. 2023 a)
    
    12.1. Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
    Quality Evaluation and Data Extraction Information for Physical and Chemical Properties
    (	2023f)
    
    12.2. Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
    Quality Evaluation and Data Extraction Information for Environmental Fate and Transport
    (	!23d)
    
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    3343
    
    3344
    
    3345
    
    3346
    
    3347
    
    3348
    
    3349
    
    3350
    
    3351
    
    3352
    
    3353
    
    3354
    
    3355
    
    3356
    
    3357
    
    3358
    
    3359
    
    3360
    
    3361
    
    3362
    
    3363
    
    3364
    
    PUBLIC RELEASE - DO NOT CITE OR QUOTE
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    12.3.	Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
    Quality Evaluation and Data Extraction Information for Environmental Release and
    Occupational Exposure (U.S. EPA. 2023 e)
    
    12.4.	Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
    Quality Evaluation Information for General Population, Consumer, and Environmental
    Exposure. (	23 u)
    
    12.5.	Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
    Extraction Information for General Population, Consumer, and Environmental Exposure (U.S.
    EPA. 2023d
    
    12.6.	Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
    Quality Evaluation Information for Human Health Hazard Epidemiology (	20231)
    
    12.7.	Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
    Quality Evaluation Information for Human Health Hazard Animal Toxicology (
    
    2023h")
    
    12.8.	Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
    Quality Evaluation Information for Environmental Hazard (	E023D
    
    12.9. Draft Risk Evaluation for Formaldehyde - Systematic Review Supplemental File: Data
    Extraction Information for Environmental Hazard and Human Health Hazard Animal
    Toxicology and Epidemiology (	Z023b)
    
    13. Draft Unreasonable Risk Determination for Formaldehyde
    
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    3365	Appendix C DETAILED EVALUATION OF POTENTIALLY
    
    3366	EXPOSED AND SUSCEPTIBLE SUBPOPULATIONS
    
    3367	C.l PESS Based on Greater Exposure
    
    3368	In this section, EPA addresses potentially exposed populations expected to have greater exposure to
    
    3369	formaldehyde. Table Apx C-l presents the quantitative data sources that were used in the PESS
    
    3370	exposure analysis for incorporating increased background and COU-specific exposures.
    
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    Table Apx (
    
    ^-1. PESS Based on Greater Exposure
    
    Category
    
    Subcategory
    
    Increased Exposure from
    OtherSources
    
    Increased Exposure from TSCA COUs
    
    Quantitative Data Sources
    
    Lifestage
    
    Embryo/fetus
    
    • EPA did not identify other sources of
    increased exposure anticipated for this
    lifestage.
    
    • EPA did not identify sources of increased
    TSCACOU exposure anticipated for this
    lifestage.
    
    • EPA did not quantify exposures
    specific to this lifestage.
    
    Pregnant people
    
    • EPA did not identify other sources of
    increased exposure anticipated for this
    lifestage.
    
    • EPA did not identify sources of increased
    TSCA COU exposure anticipated for this
    lifestage.
    
    • EPA did not quantify exposures
    specific to this lifestage
    
    Children
    
    (infants, toddlers)
    
    • EPA did not identify other sources of
    increased exposure anticipated for this
    lifestage.
    
    •	For air exposures, the impacts of lifestage
    differences were not able to be adequately
    quantified and so the air concentrations are
    used for all lifestages.
    
    •	Consumer exposure scenarios include
    lifestage-specific exposure factors for
    adults, children, and infants (U.S. EPA.
    2024d)
    
    •	Based on pchem properties and a lack of
    studies evaluating potential for
    accumulation in human milk following
    inhalation, dermal or oral exposures, EPA
    did not quantitatively evaluate the human
    milk pathway. This is a remaining source
    of uncertainty.
    
    •	In the consumer exposure assessment, EPA
    also considered potential oral exposure
    associated with mouthing behaviors in
    infants and vouns children (U.S. EPA.
    2024d). however EPA did not have
    sufficient information on this exposure
    route to quantify risks.
    
    • Lifestage specific consumer exposure
    scenarios for infants, children, and
    adults are based on information from
    U.S. EPA (2005a")and U.S. EPA
    (2011).
    
    Older Adults
    
    • EPA did not identify other sources of
    increased exposure anticipated for this
    lifestage.
    
    • EPA did not identify sources of increased
    COU or pathway specific exposure for
    this lifestage.
    
    • EPA did not quantify exposures
    specific to this lifestage.
    
    Sociodemo-
    
    graphic
    
    factors
    
    Race/Ethnicity
    
    • EPA did not identify specific data on
    other sources of increased exposure
    associated with race/ethnicity.
    
    • EPA did not identify specific data on
    increased COU or pathway specific
    exposure associated with race/ethnicity.
    
    • EPA did not quantify exposures
    associated with race/ethnicity.
    
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    Category
    
    Subcategory
    
    Increased Exposure from
    OtherSources
    
    Increased Exposure from TSCA COUs
    
    Quantitative Data Sources
    
    
    
    Socioeconomic
    status
    
    • EPA did not identify specific data on
    other sources of increased exposures
    associated with socioeconomic status.
    
    • EPA did not identify specific data on
    increased COU or pathway specific
    exposure associated with socioeconomic
    status.
    
    • EPA did not directly quantify
    exposures associated with
    socioeconomic status.
    
    Unique
    Activities
    
    Subsistence Fishing
    
    • EPA did not identify other sources of
    increased exposure associated with
    subsistence fishing or other exposure
    scenarios unique to tribes or other groups.
    
    • EPA did not identify sources of increased
    COU or pathway specific exposure for
    subsistence fishing or other exposure
    pathways unique to tribes or other groups.
    
    • EPA did not quantify exposures
    associated with subsistence fishing.
    
    Lifestyle
    
    Smoking
    
    • EPA identified smoking as an additional
    other source of exposure to formaldehyde
    that may increase aggregate exposure for
    smokers and people exposed to second-
    hand smoke. To some degree,
    formaldehyde exposure from smoking is
    indirectly accounted for in some indoor
    air monitoring data described in Section
    5.2.3.1, but it is not directly quantified.
    
    • EPA did not identify sources of increased
    COU or pathway specific exposure for
    smoking or other lifestyle factors.
    
    • EPA did not directly quantify
    exposures associated with smoking.
    
    Geography
    
    Living in proximity
    to sources of
    formaldehyde
    releases to outdoor
    air
    
    • EPA identified living near major
    roadways or in areas with frequent
    exposure to wildfire smoke as potential
    sources of increased exposure to
    formaldehyde for some populations. To
    some degree, ambient air monitoring data
    may indirectly account for some of these
    sources but they are not directly
    quantified. These other sources of
    formaldehyde are a source of uncertainty
    that is not directly incorporated into risk
    estimates for outdoor air exposures.
    
    • EPA evaluated risks to communities in
    proximity to sites where formaldehyde is
    released to ambient air (Section 5.2.4). In
    the environmental release assessment,
    EPA mapped tribal lands in relation to air,
    surface water and ground water releases
    of formaldehyde to identify potential for
    increased exposures for tribes due to
    geographic proximity (U.S. EPA, 2024g).
    
    •	EPA quantified exposures for
    communities in proximity to release
    sites using air concentrations modeled
    based on releases reported to TRI, as
    described in U.S. EPA (2024e) and
    Section 5.2.4
    
    •	EPA did not directly quantify
    exposures associated with living near
    roadways or other sources of
    formaldehyde in outdoor air.
    
    Other
    
    chemical and
    non-chemical
    stressors
    
    Built Environment
    
    • EPA identified the built environment
    (including building materials and other
    products) as source of increased exposure
    to formaldehyde associated with other
    sources. Indoor air concentrations
    assessed in Section 4.2.3 incorporate both
    TSCA and other sources of formaldehyde
    in indoor air.
    
    • EPA identified the built environment
    (including building materials and other
    products) as a source of increased
    exposure to formaldehyde associated with
    COUs. Indoor air concentrations assessed
    in Section 4.2.3 incorporate both TSCA
    and other sources of formaldehyde in
    indoor air.
    
    • EPA quantified exposures associated
    with specific TSCA COUs based on
    2016 and 2020 Chemical Data
    
    RcDortirm (U.S. EPA. 2020a. 2016a).
    the Formaldehyde and
    Paraformaldehyde Use Report (U.S.
    EPA, 2020d) and product weight
    fractions and densities reported in
    
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    Category
    
    Subcategory
    
    Increased Exposure from
    OtherSources
    
    Increased Exposure from TSCA COUs
    
    Quantitative Data Sources
    
    
    
    
    
    
    
    
    
    chemical safety data sheets (SDSs)
    identified through product-specific
    internet searches; EPA quantified
    exposures and risks associated with
    aggregate indoor air based on a range
    of monitoring data described in the
    Indoor Air Assessment (TJ.S. EPA.
    2024j).
    
    • EPA did not directly quantify indoor
    air exposures associated with other
    sources.
    
    Occupational
    
    Workers and
    occupational non-
    users
    
    • EPA identified firefighters as an
    occupational group with increased
    exposure to formaldehyde associated with
    combustion containing building materials
    with high concentrations to formaldehyde.
    While combustion exposures are beyond
    the scope of this assessment, this is a
    remaining source of uncertainty in
    characterizing aggregate exposures for
    some groups.
    
    • EPA identified all occupational exposure
    scenarios as a potential source of exposure
    to formaldehyde. Those with higher
    frequency or higher duration exposures
    are expected to have the greatest
    exposures and risks. EPA evaluated risks
    for a range of occupational exposure
    scenarios that increase exposure to
    formaldehyde, including manufacturing,
    processing, and use of formulations
    containing formaldehyde. EPA evaluated
    risks for central tendency and high-end
    exposure estimates for each of these
    scenarios (Section 5.2.1).
    
    • EPA quantified occupational
    exposures associated with TSCA
    COUs based on a range of COU-
    specific data, including monitoring
    data from OSHA and NIOSH and
    modeled air concentrations. Specific
    data sources are described in detail in
    the Draft Occupational Exposure
    Assessment (US. EPA. 2024k).
    
    Consumer
    
    High frequency
    consumers
    
    • EPA identified dietary exposures through
    food, food packaging, drugs, and personal
    care products that contain formaldehyde
    as other sources that may contribute to
    total formaldehyde exposure. These
    exposures are beyond the scope of this
    assessment and are a source of uncertainty
    in characterizing aggregate exposures.
    
    •	Consumer products designed for children
    (e.g., children's toys) may lead to elevated
    exposures for children and infants.
    
    •	EPA identified all consumer exposure
    scenarios involving TSCA COUs as
    potential sources of exposure to
    formaldehyde. Those with higher
    frequency and/or higher duration
    exposures are expected to have the
    greatest exposures and risks.
    
    • EPA quantified consumer exposure
    (U.S. EPA. 2024d) based on the
    Formaldehyde and Paraformaldehyde
    Use Reoort (U.S. EPA. 2020d) and
    the Exposure Factors Handbook (U.S.
    EPA. 2011) (Ch. 17).
    
    High duration
    consumers
    
    3372
    
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    3373	C.2 PESS Based on Greater Susceptibility
    
    3374	In this section, EPA addresses subpopulations and lifestages expected to be more susceptible to
    
    3375	formaldehyde exposure than others. This discussion draws heavily from the recent summary of
    
    3376	susceptible populations and lifestages included in the draft IRIS assessment. Table Apx C-2. presents
    
    3377	the data sources that were used in the PESS analysis evaluating susceptible subpopulations and identifies
    
    3378	whether and how the subpopulation was addressed quantitatively in the risk evaluation of formaldehyde.
    
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    3379 Table Apx C-2. Susceptibility Category, factors, and evidence for PESS susceptibility
    
    Susceptibility
    Category
    
    Specific
    Factors
    
    Direct Evidence this Factor
    Modifies Susceptibility to Formaldehyde
    
    Description of Interaction
    
    Key Citations
    
    Indirect Evidence of Potential Impact
    through Target Organs or Biological
    Pathways Relevant to Formaldehyde
    
    Description of
    Interaction
    
    Key Citations
    
    Incorporation of Each Factor into
    the Risk Evaluation
    
    Embryos/
    fetuses/infants
    
    Infants and
    children
    
    Lifestage
    
    Pregnant
    women
    
    Males of
    
    reproductive
    
    age
    
    Direct quantitative human and
    animal evidence for developmental
    toxicity following inhalation
    exposure (e.g., decreased fertility,
    increased spontaneous abortions and
    changes in brain structures).
    
    Taskinen et al. (1999)
    John et al. (1994)
    Sarsilniaz et al.
    
    (2007)
    
    Asian et al. (2006)
    
    Hazard value for chronic inhalation is
    supported in part by dose-response
    information on female reproductive
    effects and developmental toxicity and
    is expected to be protective of these
    endpoints
    
    In some studies, children appear to
    be more susceptible than adults to
    respiratory effects of formaldehyde.
    
    Early life exposures to chemicals
    with a mutagenic mode of action
    may increase cancer risk. EPA has
    concluded that the evidence is
    sufficient to conclude that a
    mutagenic mode of action of
    formaldehyde is operative in
    formaldehyde-induced
    nasopharyngeal carcinogenicity.
    
    Bateson and
    
    Schwartz (2008)
    Venn et al. (2003)
    
    Annesi-Maesano et
    
    al. (2012)
    
    Krzyzaiiowski et al.
    
    Developing lungs
    until age 6-8,
    narrower airways
    Different expression
    of enzymes
    responsible for
    metabolizing
    formaldehyde
    
    Bateson and
    
    Schwartz (2008)
    
    Thompson et al.
    (2009)
    
    Hazard value for chronic inhalation is
    based in part on dose-response
    information on asthma
    prevalence/asthma control in children.
    
    ADAFs are applied to nasopharyngeal
    cancer risk estimates to account for
    increased susceptibility to cancer
    following exposure during early life.
    
    (1990).
    
    U.S. EPA (2005b)
    
    No direct evidence identified
    
    Pregnant women may
    have increased
    sensitivity to the
    development and
    exacerbation of atopic
    eczema following
    exposure to
    formaldehyde
    
    Matsunaga et al.
    
    (2008)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    
    UFh
    
    Direct quantitative evidence in
    humans and animals evidence for
    reduced fertility following inhalation
    exposure
    
    Possible contributors
    to male reproductive
    effects/infertility (see
    also factors in other
    rows):
    
    •	Enlarged veins of
    testes
    
    •	Trauma to testes
    
    CDC (2023b)
    
    Hazard value for chronic inhalation is
    supported in part by dose-response
    information on male reproductive
    toxicity and is expected to be
    protective of these endpoints
    
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    Susceptibility
    Category
    
    Specific
    Factors
    
    Direct Evidence this Factor
    Modifies Susceptibility to Formaldehyde
    
    Indirect Evidence of Potential Impact
    through Target Organs or Biological
    Pathways Relevant to Formaldehyde
    
    Incorporation of Each Factor into
    the Risk Evaluation
    
    Description of Interaction
    
    Key Citations
    
    Description of
    Interaction
    
    Key Citations
    
    
    
    
    
    
    
    
    
    • Anabolic steroid
    or illicit drug use
    Cancer treatment
    
    
    
    
    
    Lifestage
    
    Older adults
    
    No direct evidence identified
    
    -
    
    Older adults may have
    reduced metabolism
    and higher rates of
    chronic diseases that
    may increase
    susceptibility
    
    -
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    
    UFh
    
    Pre-existing
    disease or
    disorder
    
    Health
    outcome/
    target organs
    
    A few epidemiological studies found
    that individuals with asthma and
    allergies were more susceptible to
    the deterioration of respiratory
    function after being exposed to
    formaldehyde than those without
    these conditions.
    
    Evidence from human and animal
    studies indicated that individuals
    with pre-existing nasal damage or a
    history of respiratory issues were
    more susceptible to developing
    formaldehyde induced nasal cancer.
    
    Krzyzanowski et al,
    (1990)
    
    Kriebel et al, (1993)
    
    Woutersen et al,
    
    (1989)
    
    Appelman et al,
    
    (1988)
    
    Falk et al, (1994)
    
    Individual variations
    in nasal anatomy and
    soluble factors in the
    upper respiratory tract
    can potentially
    influence the uptake
    of highly reactive
    gases like
    
    formaldehyde. This
    variability could
    possibly lead to
    differences in the
    distribution of inhaled
    formaldehyde and
    susceptibility to its
    health effects.
    
    ICRP (1994)
    Santiago et al,
    
    Q
    
    Singh et al,
    (1998)
    
    Acute inhalation hazard values are
    based in part on dose-response
    information in humans already
    identified as sensitive to
    formaldehyde in dermal patch test
    studies.
    
    No direct quantitative adjustment to
    chronic inhalation, oral or dermal
    hazard values or risk estimates; Use of
    UFh
    
    Lifestyle
    activities
    
    Smoking
    
    No direct evidence identified
    
    
    
    Heavy smoking may
    increase susceptibility
    to formaldehyde
    toxicity. However, it
    is unclear if this
    increased sensitivity
    is due to additional
    formaldehyde
    exposure or other
    chemicals in cigarette
    smoke.
    
    Fishbein (1992)
    CDC (2023a)
    CDC (2023b)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    UFh
    
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    Susceptibility
    Category
    
    Lifestyle
    activities
    
    Specific
    Factors
    
    Direct Evidence this Factor
    Modifies Susceptibility to Formaldehyde
    
    Indirect Evidence of Potential Impact
    through Target Organs or Biological
    Pathways Relevant to Formaldehyde
    
    Incorporation of Each Factor into
    the Risk Evaluation
    
    Description of Interaction
    
    Key Citations
    
    Description of
    Interaction
    
    Key Citations
    
    Alcohol
    consumption
    
    No direct evidence identified
    
    
    
    Chronic alcohol
    consumption may
    affect the
    susceptibility to
    reproductive and
    cancer related health
    outcomes.
    
    CDC (2023a)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    
    UFh
    
    Physical
    activity
    
    Studies observed that prolonged
    physical activity increased an
    individual's susceptibility to
    formaldehyde induced respiratory
    impairments. These studies
    demonstrated that those who were
    exposed to formaldehyde after 15
    minutes of exercise experienced
    more significant declines in lung
    function compared to those who had
    shorter exercise sessions or no
    exercise at all.
    
    Green et al, (1987)
    Green et al, (1989)
    
    Insufficient activity
    may increase
    susceptibility to
    multiple health
    outcomes
    
    Overly strenuous
    activity may also
    increase
    susceptibility.
    
    CDC (2022)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    UFh
    
    Sociodemo-
    graphic status
    
    Race/ethnicity
    
    An epidemiological study suggests a
    racial difference in susceptibility to
    formaldhyde toxicity, as nonwhite
    individuals were found to have
    higher mortality rates for
    nasopharyngeal cancer and multiple
    myeloma compared to their white
    counterparts.
    
    Hayes et al, (1990)
    
    
    
    
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    UFh
    
    Socio-
    economic
    status
    
    No direct evidence identified
    
    
    
    Individuals with
    lower socioeconomic
    status may experience
    adverse health
    
    ODPHP (2023b)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    UFh
    
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    Susceptibility
    Category
    
    Sociodemo-
    graphic status
    
    Specific
    Factors
    
    Direct Evidence this Factor
    Modifies Susceptibility to Formaldehyde
    
    Indirect Evidence of Potential Impact
    through Target Organs or Biological
    Pathways Relevant to Formaldehyde
    
    Incorporation of Each Factor into
    the Risk Evaluation
    
    Description of Interaction
    
    Key Citations
    
    Description of
    Interaction
    
    Key Citations
    
    
    
    
    
    
    
    outcomes due to
    unmet social needs,
    environmental factors,
    and limited access to
    healthcare services.
    
    
    
    
    
    Sex/gender
    
    A higher prevalence of burning or
    tearing eyes was observed among
    women compared to men, suggesting
    that women may be more sensitive to
    the irritant properties of
    formaldehyde on the eyes and upper
    respiratory tract.
    
    Several animal studies showed that
    males exhibit a higher incidence of
    lesions in the upper respiratory tract
    than females.
    
    Evidence from epidemiological
    studies and animal models indicates
    that formaldehyde exposure can lead
    to male reproductive impairments,
    reduced fertility, and increased risk
    of miscarriage in women
    
    Liu et al, (1991)
    
    
    
    
    
    Both acute and chronic inhalation
    hazard values are based in part on
    epidemiological studies include that
    include both male and female
    subjects,
    
    Woutersen et al,
    
    (1987)
    
    Zwart et al, (1988)
    
    Maronpot et al,
    
    (1986)
    
    Kerns et al, (1983)
    Taskinen et al, (1999)
    
    John et al, (1994)
    Wang et al, (2015)
    
    Nutrition
    
    Diet
    
    No direct evidence identified
    
    
    
    An antioxidant
    deficient diet may
    exacerbate
    inflammatory
    responses, primarily
    due to formaldehyde's
    well-known
    inflammatory
    properties.
    
    Obesity can increase
    susceptibility to
    cancer.
    
    CDC (2023a)
    CDC (2020)
    CDC (2023c)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    
    UFh
    
    Malnutrition
    
    No direct evidence identified
    
    
    
    Micronutrient
    malnutrition can
    result in various
    
    CDC (2021)
    CDC (2023c)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    UFh
    
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    Susceptibility
    Category
    
    Specific
    Factors
    
    Direct Evidence this Factor
    Modifies Susceptibility to Formaldehyde
    
    Indirect Evidence of Potential Impact
    through Target Organs or Biological
    Pathways Relevant to Formaldehyde
    
    Incorporation of Each Factor into
    the Risk Evaluation
    
    Description of Interaction
    
    Key Citations
    
    Description of
    Interaction
    
    Key Citations
    
    
    
    
    
    
    
    
    
    conditions, such as
    birth defects, maternal
    and infant mortality,
    preterm birth, low
    birth weight, poor
    fetal growth,
    childhood blindness,
    and undeveloped
    cognitive ability.
    
    
    
    
    
    Nutrition
    
    
    
    
    
    
    
    Deficiencies in
    micronutrients may
    increase an
    individual's
    susceptibility to the
    adverse health effects
    of formaldehyde,
    particularly
    respiratory
    impairments. This is
    due to the critical role
    of micronutrients in
    maintaining robust
    immune function,
    potent antioxidant
    defenses, and the
    structural integrity of
    the respiratory
    system.
    
    
    
    
    
    Genetics/
    epigenetics
    
    Target organs
    
    No direct evidence identified
    
    
    
    Genetic disorders,
    such as Klinefelter's
    syndrome, Y-
    chromosome
    microdeletion,
    myotonic dystrophy
    can affect male
    reproduction/fertility
    
    CDC (2023b)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    
    UFh
    
    
    
    Toxicokinetics
    
    Studies suggested that certain genetic
    variants could impair the activity of
    ADH and ALDH enzyme. This
    
    Wu et al. (2007)
    Hedberg et al, (2001)
    
    
    
    
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    UFh
    
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    Susceptibility
    Category
    
    Specific
    Factors
    
    Direct Evidence this Factor
    Modifies Susceptibility to Formaldehyde
    
    Indirect Evidence of Potential Impact
    through Target Organs or Biological
    Pathways Relevant to Formaldehyde
    
    Incorporation of Each Factor into
    the Risk Evaluation
    
    Description of Interaction
    
    Key Citations
    
    Description of
    Interaction
    
    Key Citations
    
    
    
    
    
    potential impairment could reduce
    the clearance of formaldehyde,
    thereby increasing susceptibility to
    adverse health effects associated
    
    Deltour et al, (1999)
    Tan et al, (2018)
    
    
    
    
    
    
    
    
    
    
    
    with formaldehyde exposure.
    
    
    
    
    
    
    
    
    
    Genetics/
    epigenetics
    
    
    
    Studies have demonstrated that
    genetic variations in ADH3 and
    ALDH2 genes have been associated
    to higher susceptibility to asthma and
    CNS toxicity, while polymorphism
    in genes related to DNA repair, such
    as XRCC3, have been shown to
    impact susceptibility to formaldhyde
    
    Nakaniura et al.
    
    
    
    
    
    
    
    
    
    induced geno toxicity.
    
    Studies in experimental animals with
    genetically modified ALDH2 and
    ALDH5 genes, responsible for
    eliminating endogenous
    formaldhyde, suggested that
    variations in these genes could
    potentially increase susceptibility to
    geno toxicity.
    
    Although some studies have
    suggested that specific genetic
    variants may influence susceptibility
    to formaldehyde toxicity, their
    findings have not been conclusive.
    
    (2020)
    
    Dingier et al, (2020)
    
    
    
    
    
    
    
    Other
    
    chemical and
    nonchemical
    stressors
    
    Built
    
    environment
    
    No direct evidence identified
    
    
    
    Poor quality housing
    often contains
    environmental
    triggers of asthma
    such as pests, mold,
    dust, building
    materials that may
    exacerbate reduced
    asthma control
    associated with
    
    ODPHP (2023a)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    
    UFh
    
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    Susceptibility
    Category
    
    Specific
    
    Factors
    
    Direct Evidence this Factor
    Modifies Susceptibility to Formaldehyde
    
    Indirect Evidence of Potential Impact
    through Target Organs or Biological
    Pathways Relevant to Formaldehyde
    
    Incorporation of Each Factor into
    the Risk Evaluation
    
    Description of Interaction
    
    Key Citations
    
    Description of
    Interaction
    
    Key Citations
    
    
    
    
    
    
    
    
    
    formaldehyde
    exposure
    
    
    
    
    
    
    
    Social
    
    environment
    
    No direct evidence identified
    
    
    
    Poverty, violence, as
    well as other social
    factors may make
    some populations
    more susceptible to
    the health effects
    associated with
    formaldehyde
    exposure.
    
    CDC (2023d)
    ODPHP (2023c)
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    
    UFh
    
    Other
    
    chemical and
    nonchemical
    stressors
    
    Chemical co-
    exposures
    
    Several studies have demonstrated
    that co-exposure to formaldehyde
    and other substances, including
    environmental pollutants and dietary
    components, could potentially affect
    respiratory health, hypersensitivity
    reactions, or lung function.
    
    While studies have indicated that
    certain dietary components, such as
    methanol and caffeine can contribute
    to the endogenous production of
    formaldehyde in non-respiratory
    tissues, the extent to which this
    influences susceptibility to inhaled
    formaldehyde remains unclear.
    
    Environmental tobacco smoke
    exposure has been associated with an
    increased likelihood of
    hypersensitivity responses in
    individuals concurrently exposed to
    formaldehyde. Studies suggest that
    exposure to tobacco smoke may
    potentiate the effects of
    formaldehyde or even trigger such
    responses at lower formaldehyde
    
    Besaratinia et al.
    2014
    
    Fang et al. 2004
    Gavriliu et al. 2013
    
    Hohnloser et al,
    
    (1980)
    
    Riess et al, (2010)
    
    Summers et al,
    
    (2012)
    
    Krzyzanowski et al,
    (1990)
    
    
    
    
    
    No direct quantitative adjustment to
    hazard values or risk estimates; Use of
    UFh
    
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    Susceptibility
    Category
    
    Specific
    Factors
    
    Direct Evidence this Factor
    Modifies Susceptibility to Formaldehyde
    
    Indirect Evidence of Potential Impact
    through Target Organs or Biological
    Pathways Relevant to Formaldehyde
    
    Incorporation of Each Factor into
    the Risk Evaluation
    
    Description of Interaction
    
    Key Citations
    
    Description of
    Interaction
    
    Key Citations
    
    
    
    concentrations, particularly in
    children and nonsmoking adults
    
    
    
    
    
    
    
    
    
    3380
    
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    3386
    
    3387
    
    3388
    
    3389
    
    3390
    
    3391
    
    3392
    
    3393
    
    3394
    
    3395
    
    3396
    
    3397
    
    3398
    
    3399
    
    3400
    
    3401
    
    3402
    
    3403
    
    3404
    
    3405
    
    3406
    
    3407
    
    3408
    
    3409
    
    3410
    
    3411
    
    3412
    
    3413
    
    3414
    
    3415
    
    3416
    
    3417
    
    3418
    
    3419
    
    3420
    
    3421
    
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    Appendix D AMBIENT AIR RISK ESTIMATES - COMMERCIAL
    USES
    
    The ambient air exposure assessment for formaldehyde quantitatively evaluates exposures resulting
    from industrial releases of formaldehyde to ambient air. EPA expects that releases resulting from TSCA
    industrial COUs have larger point source emissions than the air emissions resulting from commercial
    uses.
    
    As discussed in the Environmental Release Assessment (	)2Ag), where available, EPA used
    
    TRI and NEI to inform air releases from commercial COUs. However, facilities are only required to
    report to TRI if the facility has 10 or more full-time employees; is included in an applicable North
    American Industry Classification System (NAICS) code; and manufactures, processes, or uses the
    chemical in quantities greater than a certain threshold. Reporting to NEI depends on submissions
    voluntarily provided by state, local, and tribal agencies and is supplemented by data from other EPA
    programs. For NEI, the general threshold for major source is the potential to emit more than 10 tons per
    year for a single Hazardous Air Pollutant (HAP), or 25 tons/year for any combination of HAPs.
    
    Due to these limitations, commercial sites that use formaldehyde and/or formaldehyde-containing
    products may not report to TRI or NEI and are therefore not included in these datasets.
    
    EPA did not quantify releases and therefore ambient air risk estimates for the following COUs:
    
    •	Distribution in commerce
    
    •	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
    
    •	Commercial use - chemical substances in products not described by other codes - other:
    laboratory chemicals; and
    
    •	Commercial use - chemical substances in automotive and fuel products- automotive care
    products; lubricants and greases; fuels and related products.5
    
    EPA discusses the release potential for each COU in in the Draft Environmental Release Assessment for
    Formaldehyde (	) based on the available information. In general, EPA expects industrial
    
    COUs to be the drivers of risk for ambient air from the TSCA COUs within the scope of this draft risk
    evaluation.
    
    For the following commercial COUs
    
    •	Commercial use - chemical substances in furnishing treatment/care products- floor coverings;
    foam seating and bedding products; furniture and furnishings not covered elsewhere; cleaning
    and furniture care products; fabric, textile, and leather products not covered elsewhere-
    construction
    
    •	Commercial Use - chemical substances in construction, paint, electrical, and metal products-
    adhesives and sealants; paint and coatings
    
    5 Use of fuels may be associated with petroleum refinery and utilities, however, note formaldehyde from combustion sources
    is not assessed as an independent COU subcategory in this risk evaluation
    
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    3428
    
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    3430
    
    3431
    
    3432
    
    3433
    
    3434
    
    3435
    
    3436
    
    3437
    
    3438
    
    3439
    
    3440
    
    3441
    
    3442
    
    3443
    
    3444
    
    3445
    
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    •	Commercial Use - chemical substances in furnishing treatment/care products -
    building/construction materials - wood and engineered wood products; building/ construction
    materials not covered elsewhere
    
    EPA expects emissions may be similar to the construction sector, which has cancer risk estimate lower
    than 1 x 10~6 based on 100 to 1,000 m from the release site for the 95th percentile annual reported release
    amount.
    
    For the following commercial COUs
    
    •	Commercial use - chemical substances in electrical products - electrical and electronic products
    
    •	Commercial use - chemical substances in metal products - metal products not covered elsewhere
    
    EPA expects emissions may be similar to the electrical equipment, appliance, and component
    manufacturing and fabricated metal product manufacturing sector, which has cancer risk estimate lower
    than 1 x 10~6 based on 100 to 1,000 m from the release site for the 95th percentile annual reported release
    amount.
    
    For the following commercial COU, Commercial use - chemical substances in agriculture use products
    - lawn and garden products, EPA expects emissions may be similar to the agriculture, forestry, fishing,
    and hunting sector, which has risk estimate lower than 1 x 10~6 based on 100 to 1,000 m from the release
    site for the 95th percentile annual reported release amount.
    
    For the following commercial COUs
    
    •	Commercial use - chemical substances in packaging, paper, plastic, hobby products - paper
    products; plastic and rubber products; toys, playground, and sporting equipment
    
    •	Commercial use - chemical substances in packaging, paper, plastic, hobby products- arts, crafts,
    and hobby materials
    
    •	Commercial use - chemical substances in packaging, paper, plastic, hobby products- ink, toner,
    and colorant products; photographic supplies
    
    EPA expects emissions may be similar to the Printing and Related Support Activities & Photographic
    Film Paper, Plate, and Chemical Manufacturing sector, which have risk estimates lower than 1 x 10~6
    based on 100 to 1,000 m from the release site for the 95th percentile annual reported release amount.
    EPA does, however, note that printing operations that use printing ink, toner, or colorant products
    containing formaldehyde may occur at industrial sites such as those included in Paper Manufacturing,
    which has a cancer risk estimate of 1.24xl0~5.
    
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    3477
    
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    3479
    
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    3490
    
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    Appendix E DRAFT OCCUPATIONAL EXPOSURE VALUE
    DERIVATION
    
    EPA has calculated a draft 8-hour existing chemical occupational exposure value to summarize the
    occupational exposure scenario and sensitive health endpoints into a single value. EPA calculated the
    draft value rounded to 0.011 ppm (14 |ig/m3) for inhalation exposures to formaldehyde as an 8-hour
    TWA and for consideration in workplace settings (see Appendix E. 1) based on the chronic and
    intermediate non-cancer hazards value for respiratory effects.
    
    TSCA requires risk evaluations to be conducted without consideration of costs and other non-risk
    factors, and thus this draft occupational exposure value represents a risk-only number. If risk
    management for formaldehyde follows the final risk evaluation, EPA may consider costs and other non-
    risk factors, such as technological feasibility, the availability of alternatives, and the potential for critical
    or essential uses. In general, any existing chemical exposure limit (ECEL) used for occupational safety
    risk management purposes could differ from the draft occupational exposure value presented in this
    appendix based on additional consideration of exposures and non-risk factors consistent with TSCA
    section 6(c), and this is certain to be the case for formaldehyde. The unique challenge associated with
    this evaluation is that the formaldehyde released from activities and products that are subject to TSCA is
    mixed in with the formaldehyde released from all sources as described in the executive summary, which
    could raise a challenge if/when an implementable regulatory occupational exposure limit is designed.
    More specifically, the draft occupational exposure value of 14 |ig/m3 for formaldehyde is below -20 -
    40 |ig/mJ (50th to 95th percentile of concentrations measured in AHHS II for indoor air in residential
    settings)for indoor air. EPA must therefore consider this unique challenge if it ultimately designs and
    proposes a regulatory limit for occupational inhalation exposures to formaldehyde.
    
    This calculated draft value for formaldehyde represents the exposure concentration below which
    workers and occupational non-users are not expected to exhibit any appreciable risk of adverse
    toxicological outcomes, accounting for potentially exposed and susceptible populations (PESS). It is
    derived based on the most sensitive human health effect relative to benchmarks and standard
    occupational scenario assumptions of 8 hours/day, 5 days/week exposures for a total of 250 days
    exposure per year, and a 40-year working life.
    
    EPA expects that at the draft occupational exposure value of 0.011 ppm (14 |ig/m3), a worker or ONU
    also would be protected against respiratory effects resulting from chronic exposures. In addition, this
    calculated draft value would protect against excess risk of nasopharyngeal cancer above the 1 x 10~4
    benchmark value resulting from lifetime exposure if ambient exposures are kept below this draft
    occupational exposure value. The acute exposure limit is unchanged for all durations of a single
    exposure and also serves as the short-term exposure limit (STEL) to protect against 15-minute
    exposures.
    
    Of the identified occupational monitoring data for formaldehyde, there have been measured workplace
    air concentrations below the calculated draft exposure value. A summary table of available monitoring
    methods from the Occupational Safety and Health Administration (OSHA) and the National Institute for
    Occupational Safety and Health (NIOSH) is included in Appendix E.2. The table covers validated
    methods from governmental agencies and is not intended to be a comprehensive list of available air
    monitoring methods for formaldehyde. The calculated draft exposure value is above the limit of
    detection (LOD) and limit of quantification (LOQ) using at least one of the monitoring methods
    identified.
    
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    The Occupational Safety and Health Administration (OSHA) set a permissible exposure limit (PEL) as
    an 8-hour TWA for formaldehyde of 0.75 ppm in 1992 (https://www.osha.eov/aimotated-pels). with an
    action level of 0.5 ppm. In addition, OSHA has set a STEL of 2 ppm. OSHA's PEL must undergo both
    risk assessment and feasibility assessment analyses before selecting a level that will substantially reduce
    risk under the Occupational Safety and Health Act. EPA's calculated draft exposure value is a lower
    value and is based on newer information and analysis from this risk evaluation.
    
    There are also recommended exposure limits established for formaldehyde by other governmental
    agencies and independent groups. The American Conference of Governmental Industrial Hygienists
    (ACGIH) set a Threshold Limit Value (TLV) at 0.1 ppm TWA and 0.3 ppm STEL in 2017. This
    chemical also has a NIOSH Recommended Exposure Limit (REL) of 0.016 ppm TWA and 15-minute
    Ceiling limit of 0.1 ppm (https://www.cdc.gov/niosh/npg/).
    
    E.l Draft Occupational Exposure Value Calculations
    
    This appendix presents the calculations used to estimate draft occupational exposure values using inputs
    derived in this draft risk evaluation. Multiple values are presented below for hazard endpoints based on
    different exposure durations. For formaldehyde, the most sensitive occupational exposure value is based
    on respiratory effects and the resulting 8-hour TWA is rounded to 14 |ig/m3. The human health hazard
    values used in these equations are based on the inhalation non-cancer hazard values and the IUR
    summarized in Table 3-1.
    
    Draft Intermediate Non-cancer Occupational Exposure Value
    
    The draft exposure value was calculated for the occupational non-cancer repeat-dose human equivalent
    concentration for respiratory effects as the concentration at which the chronic margin of exposure
    (MOE) would equal the benchmark MOE for 8-hour intermediate occupational exposures with
    EquationApx E-l:
    
    EquationApx E-l.
    
    ^intermediate
    
    		HECrepeat	ATheC repeat^. I^input
    
    ir,t*irrr,0Hint0 ~ Benchmark MOErepeat * ED*EF IRworkers
    
    0.017 ppm 24/i/d*30d 0.6125 m3/hr
    
    3 * Qh/d*22d * 1.25m3//ir = °'011 Ppm
    
    /'mgN ECELppm*MW 0.011 ppm*30.026mg
    
    t V I —- ) —	—	1	— 0.014 —-
    
    \mJ/ Molar Volume 24 45——	rnJ
    
    mol
    
    Where:
    
    Molar Volume	= 24.45 L/mol, the volume of a mole of gas at 1 atm and 25 °C
    
    MW	= Molecular weight of formaldehyde (30.026 g/mole)
    
    Draft Acute/Short-Term, Non-cancer Occupational Exposure Value
    
    The acute occupational exposure value (EVaCute), equivalent to the 15-minute STEL, was calculated as
    the concentration at which the acute MOE would equal the benchmark MOE for acute occupational
    exposures using Equation Apx E-2:
    
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    3552
    
    3553
    
    3554
    
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    3558
    
    3559
    
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    3561
    
    3562
    
    3563
    
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    EquationApx E-2.
    
    FV
    
    ^ v acute
    
    HEC,
    
    acute
    
    Benchmark MOE,
    
    acute
    
    0.5 ppm	mg
    
    —= 0.050 ppm = 0.061 —|
    10	m3
    
    Draft Chronic, Non-cancer Occupational Exposure Value
    
    The chronic occupational exposure value (EVchronic) can be calculated as the concentration at which the
    chronic MOE would equal the benchmark MOE for chronic occupational exposures. However, for
    purposes of risk management, EPA has determined that because the same critical health effect applies to
    both in both intermediate and chronic exposure contexts, the relevant averaging time should be
    considered equivalent across both exposure scenarios. Therefore, the resulting EVchromc would be the
    same as the draft exposure value based on intermediate exposures.
    
    Draft Lifetime Cancer Occupational Exposure Value
    
    The EVcancer is the concentration at which the extra cancer risk is equivalent to the benchmark cancer
    risk of 1 x 10 4:
    
    Benchmarkmnrpr ATWR	IRi
    
    EVr,
    
    1 input
    
    1X10
    
    -4
    
    IUR	ED *EF* WY lRworkers
    
    h 365 d
    
    d* y * J 1.25m3//ir
    
    7.90x10 ~3 per ppm 2h ¦¦ 250d lOv 12Sm3/hr
    
    d y 7
    
    Where:
    
    A TnECrepeat
    
    A TnECacute
    
    ATiur
    
    Benchmark MOEa
    
    Benchmark MOE,
    
    repeat
    
    Benchmarkca
    
    EV acute
    EVintermediate
    
    EVchromc
    
    EV cancer
    
    ED
    EF
    
    = 0.108 ppm = 1.33 --§
    
    m3
    
    Averaging time for the POD/HEC used for evaluating non-cancer,
    intermediate and chronic occupational risk, based on study
    conditions and/or any HEC adjustments (24 hr/day for 30 days)
    (see Section 4.2.2.1)
    
    Averaging time for the POD/HEC used for evaluating non-cancer,
    acute occupational risk, based on study conditions and/or any HEC
    adjustments (24 hr/day) (see Section 4.2.2.1)
    
    Averaging time for the cancer IUR, based on study conditions and
    any adjustments (24 hr/day for 365 days/year) and averaged over a
    lifetime (78 years) (Supplemental File: Releases and Occupational
    Exposure Assessment; Appendix B).
    
    Acute non-cancer benchmark margin of exposure, based on the
    
    total uncertainty factor of 10 (see Table 3-7)
    
    Short term non-cancer benchmark margin of exposure, based on
    
    the total uncertainty factor of 100 (see Table 3-8)
    
    Benchmark for excess lifetime cancer risk
    
    Exposure limit based on acute effects
    
    Existing chemical exposure limit (mg/m3), based on non-cancer
    effects following repeat exposures
    
    Existing chemical exposure limit (mg/m3), based on non-cancer
    effects following repeat exposures
    Exposure limit based on excess cancer risk
    Exposure duration (8 hr/day) (see Table 3-8)
    
    Exposure frequency (250 days/yr), (see Section 4.2.2.1)
    
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    HECacute or repeat	= Human equivalent concentration for acute or intermediate/chronic
    
    occupational exposure scenarios, respectively (see Tables 3-7 and
    3-8)
    
    IUR	= Inhalation unit risk (per ppm) (see Table 3-6)
    
    IR	= Inhalation rate (default is 1.25 m3/hr for workers and 0.6125 m3/hr
    
    for general population at rest)
    W7	= Working years per lifetime at the 95th percentile (40 years
    
    (Supplemental File: Releases and Occupational Exposure
    Assessment; Appendix B)
    
    Unit conversion:
    
    1 ppm = 1.23 mg/m3 (based on molecular weight of 30.026 g/mol for formaldehyde)
    
    E.2 Summary of Air Sampling Analytical Methods Identified
    
    EPA conducted a search to identify relevant NIOSH and OSHA analytical methods used to monitor for
    the presence of formaldehyde in air (see TableApx E-l). This table covers validated methods from
    governmental agencies and is not intended to be a comprehensive list of available air monitoring
    methods for formaldehyde. The sources used for the search included the following:
    
    1.	NIOSH Manual of Analytical Methods (NMAM), 5th Edition;
    
    2.	NIOSH NMAM 4th Edition: and
    
    3.	OSHA Index of Sampling and Analytical Methods.
    
    Table Apx E-l. Limit of Detection (LOD) and Limit of Quantification (LOQ) Summary for Air
    
    Sampling Analytica
    
    Methods
    
    dentified
    
    Air Sampling
    Analytical Methods"
    
    Year
    Published
    
    LOD6
    
    LOQ
    
    Notes
    
    Source
    
    NIOSH Method 2016
    
    2016
    
    0.012
    ppm
    
    N/A
    
    Estimated LOD is 0.07
    (ig/sample. The working
    range is 0.012 to 2.0 ppm
    for a 15-L sample.
    
    NIOSH Manual of
    Analytical Methods
    
    ("NMAM 2016)
    
    NIOSH Method 254lc
    
    1994
    
    0.24 ppm
    
    N/A
    
    Estimated LOD is 1
    (ig/sample. The working
    range is 0.24 to 16 ppm
    for a 15-L sample.
    
    NIOSH Manual of
    Analytical Methods,
    4th Edition
    
    ("NMAM 2541)
    
    NIOSH Method 3500d
    
    1994
    
    0.02 ppm
    
    N/A
    
    Estimated LOD is 0.5
    (ig/sample. The working
    range is 0.02 to 4 ppm for
    an 80-L sample.
    
    NIOSH Manual of
    Analytical Methods,
    4th Edition
    
    ("NMAM 3500)
    
    NIOSH Method 5700e
    
    1994
    
    0.0004
    mg/m3
    (0.0003
    ppm)
    
    N/A
    
    Estimated LOD is 0.08
    (ig/sample. The working
    range is 0.0004 to 3.8
    mg/m3 for a 1,050-L
    sample. Used for
    determination of
    formaldehyde in both
    textile and wood dusts.
    
    NIOSH Manual of
    Analytical Methods,
    4th Edition
    
    ("NMAM 5700)
    
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    Air Sampling
    Analytical Methods"
    
    Year
    Published
    
    LOD6
    
    LOQ
    
    Notes
    
    Source
    
    OSHA Method 52
    
    1989
    
    16 ppb
    
    16 ppb
    
    Detection limit and
    reliable quantification
    limit is 482 ng per sample
    (16 ppb for 24 L)
    
    OSHA Index of
    Sampling and
    Analytical Methods
    
    (OSHA 52)
    
    OSHA Method 1007/
    
    littus ://www .oslia. eov
    /sites/default/files/met
    hods/osha-1007 .odf
    
    2005
    
    0.56, 1.70, or
    0.17 ppb
    (Sampler -
    ChemDisk-
    AL, UMEx
    100, DSD-
    DNPH,
    respectively)
    
    1.88, 5.68, or
    0.58 ppb
    (Sampler -
    ChemDisk-
    AL, UMEx
    100, DSD-
    DNPH,
    respectively)
    
    Method reports
    LOD/LOQ of overall
    procedure as 0.56/1.88
    ppb for ChemDisk-AL
    samplers, 1.70/5.68 ppb
    for UMEx 100 samplers,
    and 0.17/0.58 for DSD-
    DNPH samplers
    
    OSHA Index of
    Sampling and
    Analytical Methods
    (OSHA 1007)
    
    ppm = parts per million; ppb = parts per billion; ppt = parts per trillion
    
    a EPA has additional air sampling methods targeted for measurement of ambient and indoor air, the methods
    listed in this table are air sampling for occupational exposures.
    
    b These sources cover a range of LOD including both below and above the preliminary occupational exposure
    value.c The method is suitable for the simultaneous determinations of acrolein and formaldehyde.
    
    ''This is the most sensitive formaldehyde method in the NIOSH Manual of Analytical Methods and is able to
    measure ceiling levels as low as 0.1 ppm (1 5-L sample). It is best suited for the determination of formaldehyde
    in area samples.
    
    '' Results should be considered separately from vapor-phase formaldehyde exposure; Method measures both
    "released" and formaldehyde equivalents.
    
    ' Recommends use of OSHA Method 52 when monitoring exposures resulting from the use of formalin
    solutions.
    
    3609
    
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    3623
    
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    Appendix F ACUTE AND CHRONIC (NON-CANCER AND
    CANCER) OCCUPATIONAL INHALATION
    EQUATIONS
    
    This assessment provides estimates of 15-minute peak air concentrations, short-term air concentrations,
    and full-shift (8- or 12-hour) concentrations. For calculation of risk, these exposure estimates are
    incorporated with additional parameter inputs, such as working years, exposure duration and frequency,
    and lifetime years.
    
    AC is used to estimate workplace inhalation exposures for acute risks {i.e., risks occurring after less than
    one day of exposure), per EquationApx F-l, EquationApx F-2, and EquationApx F-3 below.
    
    EquationApx F-l.
    
    C x ED x BR
    
    AC =	^	
    
    AT
    
    ri1 acute
    
    Where:
    
    AC =
    
    Acute exposure concentration
    
    C
    
    Contaminant concentration in air (TWA)
    
    ED =
    
    Exposure duration (hr/day), 0.25 hr/day
    
    BR
    
    Breathing rate ratio (unitless), 1
    
    ATacute
    
    Acute averaging time (hr), 0.25 hr
    
    ADC and LADC are used to estimate workplace exposures for non-cancer and cancer risks, respectively.
    These exposures are estimated per Equation Apx F-2, as follows:
    
    Equation Apx F-2.
    
    C x ED x EF XWY x BR
    
    ADC =	—	
    
    AT
    
    day	hr
    
    ATSC = WY X 30	24-
    
    month day
    
    day hr
    AT = WY x 365 — x 24—
    
    yr day
    
    Where:
    
    ADC =
    
    Average daily concentration used for chronic non-cancer risk calculations
    
    ED =
    
    Exposure duration (hr/day)
    
    EF
    
    Exposure frequency (day/yr)
    
    BR
    
    Breathing rate ratio (unitless),
    
    WY =
    
    Working years per lifetime (yr)
    
    ATsc =
    
    Averaging time (hr) for sub-chronic, non-cancer risk
    
    AT =
    
    Averaging time (hr) for chronic, non-cancer risk
    
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    3657
    
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    EquationApx F-3.
    
    LADC =
    
    C x ED x EF x WY x BR
    
    ATC
    
    day
    
    ATC = LT X36S — x 24
    
    yr
    
    hr
    day
    
    Where:
    
    LADC =
    
    ED =
    EF
    
    WY =
    ATc =
    LT
    
    Lifetime average daily concentration used for chronic cancer risk
    calculations
    
    Exposure duration (hr/day)
    
    Exposure frequency (day/yr)
    
    Working years per lifetime (yr),
    
    Averaging time (hr) for cancer risk
    Lifetime years (yr) for cancer risk, 78 yr
    
    For exposure duration, frequency, and working years used in this appendix, see Table Apx F-l.
    
    Table Apx F-l. Ap
    
    )endix F Formulae - Symbols, Values, and Units
    
    Symbol
    
    Value
    
    Unit
    
    ED
    
    8 or 12
    
    hour/day
    
    EF
    
    250 or 167
    
    day/year
    
    WY(ct)
    
    31
    
    years
    
    WY(he)
    
    40
    
    years
    
    AT(ct)
    
    271,560
    
    hours
    
    AT (HE)
    
    350,400
    
    hours
    
    ATC
    
    683,280
    
    hours
    
    Worker Years
    
    EPA has developed a triangular distribution for working years. EPA has defined the parameters of the
    triangular distribution as follows:
    
    •	Minimum value: BLS CPS tenure data with current employer as a low-end estimate of the
    number of lifetime working years: 10.4 years;
    
    •	Mode value: The 50th percentile tenure data with all employers from SIPP as a mode value for
    the number of lifetime working years: 36 years; and
    
    •	Maximum value; The maximum average tenure data with all employers from SIPP as a high-end
    estimate on the number of lifetime working years: 44 years.
    
    This triangular distribution has a 50th percentile value of 31 years and a 95th percentile value of 40
    years. EPA uses these values for central tendency and high-end ADC and LADC calculations,
    respectively.
    
    The BLS (U .S. BLS. 2014) provides information on employee tenure with current employer obtained
    from the CPS, which is a monthly sample survey of about 60,000 households that provides information
    on the labor force status of the civilian non-institutional population age 16 and over. CPS data are
    released every 2 years. The data are available by demographics and by generic industry sectors but are
    not available by NAICS codes.
    
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    3690
    
    3691
    
    3692
    
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    3694
    
    3695
    
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    3697
    
    3698
    
    3699
    
    3700
    
    3701
    
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    3703
    
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    The U.S. Census' 0 ; S Census Bureau. 2019a) SIPP provides information on lifetime tenure with all
    employers. SIPP is a household survey that collects data on income, labor force participation, social
    program participation and eligibility, and general demographic characteristics through a continuous
    series of national panel surveys of between 14,000 and 52,000 households (\] S Census Bureau. 2019b).
    EPA analyzed the 2008 SIPP Panel Wave 1, a panel that began in 2008 and covers the interview months
    of September 2008 through December 2008 (\] S Census Bureau. 2019a. b). For this panel, lifetime
    tenure data are available by Census Industry Codes, which can be cross walked with NAICS codes.
    
    SIPP data include fields for the industry in which each surveyed, employed individual works
    (TJBIND1), worker age (TAGE), and years of work experience with all employers over the surveyed
    individual's lifetime. Census household surveys use different industry codes than the NAICS codes used
    in its firm surveys, so these were converted to NAICS using a published crosswalk (Census Bureau,
    2012b). EPA calculated the average tenure for the following age groups: (1) workers aged 50 and older,
    (2) workers aged 60 and older, and (3) workers of all ages employed at time of survey. EPA used tenure
    data for age group "50 and older" to determine the high-end lifetime working years, because the sample
    size in this age group is often substantially higher than the sample size for age group "60 and older." For
    some industries, the number of workers surveyed, or the sample size, was too small to provide a reliable
    representation of the worker tenure in that industry. Therefore, EPA excluded data where the sample
    size is less than five from our analysis.
    
    TableApx F-2 summarizes the average tenure for workers aged 50 years and older from SIPP data.
    Although the tenure may differ for any given industry sector, there is no significant variability between
    the 50th and 95th percentile values of average tenure across manufacturing and non-manufacturing
    sectors.
    
    Table Apx F-2. Overview of Average Worker Tenure from U.S. Census SIPP (Age Group 50+)
    
    Industry Sectors
    
    Working Years
    
    Average
    
    50th
    Percentile
    
    95th
    Percentile
    
    Maximum
    
    Manufacturing sectors (NAICS 31-33)
    
    35.7
    
    36
    
    39
    
    40
    
    Non-manufacturing sectors (NAICS 42-81)
    
    36.1
    
    36
    
    39
    
    44
    
    Source: ("U.S. Census Bureau. 2019a).
    
    Note: Industries where sample size is less than five are excluded from this analysis.
    
    BLS CPS data provides the median years of tenure that wage and salary workers had been with their
    current employer. Table Apx F-3 presents CPS data for all demographics (men and women) by age
    group from 2008 to 2012. To estimate the low-end value on number of working years, EPA uses the
    most recent (2014) CPS data for workers aged 55 to 64 years, which indicates a median tenure of 10.4
    years with their current employer. The use of this low-end value represents a scenario where workers are
    only exposed to the chemical of interest for a portion of their lifetime working years, as they may
    change jobs or move from one industry to another throughout their career.
    
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    Table Apx F-3. Median Years of Tenure wit
    
    l Current Employer by Age Group
    
    Age
    
    January 2008
    
    January 2010
    
    January 2012
    
    January 2014
    
    16 years and over
    
    4.1
    
    4.4
    
    4.6
    
    4.6
    
    16 to 17 years
    
    0.7
    
    0.7
    
    0.7
    
    0.7
    
    18 to 19 years
    
    0.8
    
    1.0
    
    0.8
    
    0.8
    
    20 to 24 years
    
    1.3
    
    1.5
    
    1.3
    
    1.3
    
    25 years and over
    
    5.1
    
    5.2
    
    5.4
    
    5.5
    
    25 to 34 years
    
    2.7
    
    3.1
    
    3.2
    
    3.0
    
    35 to 44 years
    
    4.9
    
    5.1
    
    5.3
    
    5.2
    
    45 to 54 years
    
    7.6
    
    7.8
    
    7.8
    
    7.9
    
    55 to 64 years
    
    9.9
    
    10.0
    
    10.3
    
    10.4
    
    65 years and over
    
    10.2
    
    9.9
    
    10.3
    
    10.3
    
    3714
    
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    Appendix G DERMAL EXPOSURE APPROACH
    
    The dermal load (Qu) is the quantity of chemical on the skin after the dermal contact event. This value
    represents the quantity remaining after the bulk chemical formulation has fallen from the hand that
    cannot be removed by wiping the skin (e.g., the film that remains on the skin). To estimate the dermal
    load for formaldehyde for occupational and consumer uses, EPA used dermal loading based on A
    Laboratory Method to Determine the Retention of Liquids on the Surface of the Hands (	)
    
    and formaldehyde weight concentrations relevant to the occupational use or consumer product. In
    addition, only acute exposures were quantitatively assessed given the identified dermal skin sensitization
    POD is likely only relevant to acute exposures (	?24i). The supporting study measured liquid
    
    retention on the surface of hands based on indirect (i.e., contact with saturated object) contact and direct
    (i.e., immersive) contact.
    
    For consumer exposures, EPA assumes the product used may involve immersion into a liquid and that a
    pool of a liquid product was formed on the skin, or that a rag was used that reduced the evaporation of
    formaldehyde during use. A Qu of 10.3 mg/cm2 was used to approximate hand immersion and wiping
    experiments, using oil-based products expected to have longer residence times on the skin relative to
    water-based products, as reported in (	). While this is the most protective value for
    
    consumer usage of oil-based products, it may overestimate exposures in some cases including when
    using water-based liquid products. Dermal exposures are only reasonably foreseen for consumers but not
    bystanders.
    
    Owing to volatility and expected use patterns, dermal loading of formaldehyde from solid products is
    unlikely, except for certain textiles including clothing that are treated with formaldehyde in dyeing and
    wrinkle prevention step in the textile manufacturing process (Herrero et al. 2022). EPA could not
    identify supporting evidence for dermal loading exposures from the handling or wear of fabrics. The
    Agency also could not identify a diffusion coefficient of formaldehyde for clothing. Therefore, EPA had
    a low level of confidence in the estimation of dermal loading from textiles including clothing. Thus, a
    qualitative assessment is reported for this product type in the Draft Consumer Exposure Assessment for
    Formaldehyde (	).
    
    For occupational exposures, EPA uses the guidance in Updating CEB 's Methodfor Screening-Level
    Assessments of Dermal Exposure (U, c. < I1 \ 1'<) on selection of Qu values. EPA assumes routine and
    incidental contact with liquids occur for workers during routine maintenance activities, manual cleaning
    of equipment, filling drums, connecting transfer lines, sampling, and bench-scale liquid transfers. For
    this event, the memorandum uses values of 0.7 to 2.1 mg/cm2-event for routine liquid contact. EPA uses
    the maximum value of the range from the memorandum to estimate high-end dermal loads. EPA also
    included a central tendency liquid dermal loading values, EPA used the 50th percentile of the dermal
    loading results from the underlying study (	). The 50th percentile value was 1.4 mg/cm2-
    
    event for routine/incidental contact with liquids.
    
    EPA assumes routine and immersive contact with liquids occur for workers during manual spray
    applications or contact with very wet surfaces. For this event, the memorandum uses values of 1.3 to
    10.3 mg/cm2-event for liquid contact. EPA uses the maximum value of the range from the memorandum
    to estimate high-end dermal loads. EPA also included a central tendency liquid dermal loading values,
    EPA used the 50th percentile of the dermal loading results from the underlying study (\ v < < \ l
    The 50th percentile value was 3.8 mg/cm2-event for routine/incidental immersive contact with liquids.
    The dermal exposure estimates do not consider the use of gloves or other protective equipment.
    
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