U.S. Environmental Protection Agency February 2012

TSCA Work Plan Chemicals:  

Methods Document 

Environmental Protection Agency 

Office of Pollution Prevention and Toxics 

February 2012 

 
U.S. Environmental Protection Agency February 2012

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Background 

 In the Agency’s August 2011 Discussion Guide: Background and Discussion Questions for

Identifying Priority Chemicals for Review and Assessment, EPA described the two-step process the 

Agency intended to use to identify potential candidate chemicals for near-term review and assessment 

under the Toxic Substances Control Act (TSCA). The Agency intends to use these TSCA Work Plan 

Chemicals to help focus and direct the activities of the Existing Chemicals Program in the Office of 

Pollution Prevention and Toxics (OPPT). EPA invited public comment through an online discussion 

forum conducted from August 18 through September 21, 2011, as well as through a webinar and 

stakeholder meeting held on September 7, 2011. The meeting summaries and public comments are 

available for review in the docket for this activity, EPA-HQ-OPPT-2011-0516, which can be 

accessed online at http://www.regulations.gov. 

 As described in the Discussion Guide, EPA notes that identification of a chemical as a TSCA 

Work Plan Chemical does not itself constitute a finding by the Agency that the chemical presents a 

risk to human health or the environment. Such a determination would be the result of a risk 

assessment. Rather, identification of a chemical as a TSCA Work Plan Chemical indicates only that 

the Agency intends to consider it for further review. The Agency believes that identifying these 

chemicals early in the review process would afford all interested parties the opportunity to bring 

additional relevant information on those chemicals to the Agency’s attention in order to further 

inform the review. In order to take risk management actions on a chemical substance under various 

sections of TSCA, the Agency would have to make the appropriate findings required by the specific 

provisions of the statute. 

 Identification of some chemicals as TSCA Work Plan Chemicals (Work Plan) does not mean 

that EPA would not consider other chemicals for risk assessment and potential risk management 

action under TSCA and other statutes. EPA will consider other chemicals if warranted by available 

information. In addition, EPA may subsequently identify other candidates for review in addition to 

this initial group, and may adapt the factors and data sources used in this process based on the 

experience acquired during this initial phase. Further, while the chemicals identified through this 

process as TSCA Work Plan Chemicals will likely be well-characterized for hazard and have 

information indicating exposure potential, some will have more limited data and EPA will continue to 

use its TSCA information collection, testing, and subpoena authorities, including sections 4, 8, and 

11(c) of TSCA, to develop needed information on additional chemicals that currently have less robust 

hazard or exposure databases. 

Two-Step Process

 As described in the Discussion Guide, EPA’s two-step prioritization process was intended to 

select an initial group of candidate chemicals for review by using a specific set of data sources to 

identify chemicals meeting one or more of the following factors: 

 Chemicals identified as potentially of concern for children’s health (e.g., chemicals with 

reproductive or developmental effects). 

 Chemicals identified as persistent, bioaccumulative, and toxic (PBT). 

 Chemicals identified as probable or known carcinogens. 

 Chemicals used in children’s products. 
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 Chemicals used in consumer products. 

 Chemicals detected in biomonitoring programs. 

 EPA indicated the candidate chemicals from Step 1 would then be screened in Step 2 using 

information from additional exposure and hazard data sources to further analyze the chemicals and 

select specific chemicals for further assessment, including possible risk assessment and risk 

management action. 

 Based on comments received through the discussion forum, the webinar, and the stakeholder 

meeting, EPA made some adjustments both to the Step 1 factors and to the data sources utilized in 

both Step 1 and Step 2. With regard to the factors considered in Step 1, EPA added neurotoxicity to 

the initial Step 1 selection criteria because of comments noting the importance of neurotoxic effects 

to children’s health. The Agency further added respiratory sensitization to the human health factors it 

would consider in Step 2, based on public comments suggesting this endpoint as identifying possible 

contributors to childhood asthma. Several commenters also encouraged EPA to use environmental 

toxicity as a prioritization factor to populate the Step 1 group of candidate chemicals. While 

environmental toxicity is not being used as a Step 1 prioritization factor on its own, EPA notes that 

many of the PBT chemicals are classed as toxic on the basis of environmental toxicity data. The 

Agency has also specifically factored environmental toxicity into the Step 2 analysis. 

 Following public comment, EPA also adjusted the proposed data sources identified in the 

Discussion Guide, particularly for Step 2, to encompass additional sources suggested by commenters, 

including the European Chemical Substance Information System (ESIS) and the Organization for 

Economic Cooperation (OECD) eChem Portal (which includes U.S. databases). EPA also eliminated 

certain data sources, including NHATS, NHEXAS, and TEAM, on the basis of their age. Given the 

difficulty of comprehensively identifying chemicals in consumer products, particularly because the 

2006 Inventory Update Reporting (IUR) system made no distinction between commercial and 

consumer products, EPA narrowed the focus of the Step 1 prioritization factor to chemicals identified 

as being in children’s products either through IUR reporting or through the process used by 

Washington State to generate its list of children’s product chemicals. EPA notes, however, that 

chemicals identified through the application of the prioritization factors in Step 1 were further 

scrutinized in Step 2 against additional databases including the Hazardous Substance Data Bank 

(HSDB) and the Household Product Database, among others, to identify potential consumer uses. 

Derivation of the Step 1 Potential Candidate Chemicals

To generate the Step 1 chemicals meeting the Agency’s prioritization factor criteria as 

potential candidates for review and assessment, the following sources were used: 

o Carcinogenicity: 

 IRIS: 1986 Class A, B1; 1996 Known or Probable; 1999 or 2005 Carcinogenic 

 IARC Carcinogens, Group 1, 2A 

 NTP Known Carcinogens 

o PBT: 

 TRI PBT Rule

 Great Lakes Binational PBT

 Canadian P, B, and T (all three criteria met) 

 LRTAP POPS
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 Stockholm POPs 

o Children’s Health: 

 IRIS: Repro/Dev (RfD or RfC for repro or dev) 

 NTP CERHR: Infants Any Effect or Pregnant Women Any Effect 

 Cal Prop 65 Reproductive 

o Neurotoxicity: IRIS 

o Children’s Product Use: 

 Reported in products intended for use by children in 2006 IUR

 Washington State Children’s List

o Biomonitoring (both human and environmental indicative of potential human exposure):

 NHANES

 Drinking Water Contaminants

 Fish Tissue Studies

These sources produced a combined total of 1,235 chemicals, each of which matched at least 

one criterion. The resulting chemicals were then screened both for quality control to eliminate 

duplicate listings (an artifact of differences in the way the various data sources defined and reported 

chemicals), and to exclude chemicals that would not be appropriate for designation as candidates for 

near-term review and action under TSCA, either because they did not meet the intent of the 

prioritization criteria, they were not subject to action under TSCA, or they were already the subject of 

TSCA action. 

 Chemicals were excluded from identification as potential candidates for any of the following 

reasons: 

o Pesticides: Pesticides are excluded from regulation under TSCA because they are regulated 

under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). 

o Drugs, hormones, and pharmacological chemicals: Drugs are excluded from regulation 

under TSCA because they are regulated under the Federal Food, Drug, and Cosmetic Act 

(FFDCA). Hormones and pharmacological chemicals can be found in the environment when 

they are excreted or disposed of, but may not be amenable to management under TSCA. 

o Certain radioactive materials: Radioactive chemicals are generally excluded from 

regulation under TSCA as source materials, special nuclear materials, or byproduct materials 

as defined in the Atomic Energy Act and subsequent regulations. 

o Complex process streams, byproducts not commercially produced: Chemicals that are 

the reaction products of vague constituents, byproducts of complex streams, or complex 

mixtures are generally not readily definable in terms of their chemical identity and may vary 

considerably in both their composition and hazard from batch to batch, making them difficult 

to score consistently in this type of screening exercise. They were accordingly excluded. 

o Polymers: Polymers typically have physical and chemical characteristics (high molecular 

weight, low absorbance, and low reactivity) that do not generally present significant health 

hazards. Some polymers that meet certain established criteria (49 FR 46066, November 21, 

1984) have been specifically exempted from TSCA review under the new chemicals program 

because they “do not present an unreasonable risk of injury to human health or the 

environment.” Polymers were therefore excluded from the Work Plan. 

o Gases, common naturally occurring chemicals, combustion products: Chemicals that 

exist in gaseous form at normal temperatures, predominantly occur naturally in the 
U.S. Environmental Protection Agency February 2012

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environment, or are produced predominantly by combustion are generally not amenable to 

control or management under TSCA. 

o Common oils or fats, simple plant extracts: Chemicals in these categories are generally not 

anticipated to be sufficiently toxic to give rise to concerns that would make them priorities.

o Explosive, pyrophoric, or extremely reactive or corrosive chemicals: Chemicals that 

explode, burn on contact with air or water, react quickly with other chemicals, or are 

extremely corrosive are unlikely to present opportunities for human or environmental 

exposures because their high physical hazard properties make them subject to stringent 

handling requirements intended to guard against accidental exposures or releases.

o Metals principally identified as toxic to the environment: Many metals – copper, for 

example – are generally toxic to the environment, but do not present health issues to humans 

under typical conditions of use. Those metals and related compounds were excluded from the 

Work Plan, while metals with specific human health concerns were retained.

o Chemicals already the subject of Action Plans or significant regulation under TSCA: 

Polychlorinated biphenyls (PCBs) were excluded from the Work Plan because they are 

already comprehensively regulated under TSCA, which bans their manufacture, processing, 

use and distribution in commerce. Chemicals covered by Action Plans or other currently 

ongoing regulatory activities under TSCA were also excluded because they had been recently 

reviewed and are already being addressed. 

 After these chemicals were excluded and the remaining metals and their related compounds 

were grouped together rather than being identified separately, 345 chemicals remained as potential 

candidates and entered into Step 2, which is described in the next section of this paper. 

 
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Step 2 Process to Identify the TSCA Work Plan Chemicals 

Candidate Chemicals from Step 1 

Hazard Score 

3 – 1 

Based on highest scoring 

human health OR 

environmental toxicity 

endpoint 

Exposure Score 

3 – 1

Normalized from rankings 

based on use type, general 

population and environmental 

exposure, and TRI or 

surrogate release information 

If No Score for Hazard 

No Score for Exposure but a 2 or 3 

for Persistence/Bioaccumulati

Candidate for Information 

Persisten

Bioaccumulatio

3 – 1 

Normalized from 

scores for persis

bioaccumul

Chemical Score Calculation = 

Hazard Score + Exposure Score + Persistence/Bioaccumulation Score 

If Scores for All Three Components: 

Normalized and Priority-Binned, 7-9 = High 

5-6 = Moderate, 3-4 = Low 

Further Analysis Through TSCA Work Plan for High Rankings 
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Explanation of Step 2 Process

 The chemicals identified as potential candidates for review and assessment under TSCA 

based on the Step 1 prioritization factors were screened in Step 2. Chemicals were evaluated and 

received a score through the application of a numerical algorithm. This score was based on three 

characteristics: hazard, exposure, and potential for persistence and/or bioaccumulation. Using this 

system, chemicals were sorted into one of four bins. Chemicals able to be scored on all three 

characteristics were scored as High, Moderate, or Low based on their available information. 

Chemicals with High or Moderate hazard or persistence/bioaccumulation scores that could not be 

scored for exposure because of an absence of data, together with chemicals that could not be scored 

for hazard, were identified separately as potential candidates for information gathering. 

 This chemical candidate screening process is an interim evaluation only. It does not constitute 

a final Agency determination as to risk or as to whether sufficient data are available to characterize 

risk from specific chemicals on the TSCA Work Plan. Inclusion of a chemical on the Work Plan does 

not constitute any finding of risk under TSCA. This screening process is intended only to support 

initial decisions to determine the relative priority for further assessments and to identify potential data 

needs for individual chemicals or chemical groups. 

Hazard Score: 

 The Hazard Score encompasses both human health and environmental toxicity concerns. The 

specific hazard classification criteria are based on the Alternatives Assessment Criteria for Hazard 

Evaluation developed by EPA’s Design for the Environment Program (DfE). The DfE criteria for 

classifying the toxicity of specific chemicals were developed from authoritative sources including the 

United Nation’s Globally Harmonized System (GHS) for Chemical Classification and Labeling and 

other EPA programs. The data determining the score for each chemical were obtained through the 

data sources identified in Appendix A. The hazard data reviews on each chemical were not 

exhaustive and do not rise to the level of assessments. Chemicals were scored on the basis of readily 

available data, and no judgment was made concerning gaps in or completeness of the available data 

set for a given chemical. 

 The Hazard Score was determined based on 3 hazard levels, and each hazard level had a 

corresponding hazard rank (High-3, Moderate-2, and Low-1). The concentration ranges or 

characteristics that correspond with each hazard level are listed in Table 1 below. 

 Candidate chemicals from Step 1 received a hazard rank score for each of the toxicity 

endpoints that were applicable based on the data readily available for each chemical. The highest 

hazard rank score a chemical received for any single human health or environmental toxicity 

endpoint became its Hazard Score. If the review on a chemical produced a High hazard score for any 

endpoint other than acute mammalian toxicity or acute or chronic aquatic toxicity, data on other 

endpoints were not sought because they would not impact the existing High score. 

 
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Table 1. Criteria for Determining Hazard Score 

 High Moderate Low Hazard Score 

 Ranking 3 2 1

Chemical X 

Acute Mammalian 

Toxicity 

Oral LD50 (mg/kg) 

Dermal LD50 (mg/kg) 

Inhalation LC50 (gas/vapor) 

(mg/L) 

Inhalation LC50 (mist/dust) 

(mg/L/day) 

≤ 50 - 300 

≤ 200 - 1000 

≤ 2 - 10 

≤ 0.5 – 1.0 

>300 - 2000 

>1000 - 2000 

>10 - 20 

>1.0 - 5 

>2000 

>2000 

>20 

>5 

(Highest score 

from any 

toxicity 

category) 

 Carcinogenicity GHS 1A, 1B, 

GHS2 

Limited animal Negative or 

SAR 

Mutagenicity/Genotoxicity GHS 1A, 1B, 

GHS 2 

Positive in vivo

or in vitro

Negative 

 Reproductive Toxicity 

Oral (mg/kg/day) 

Dermal (mg/kg/day) 

Inhalation (gas/vapor) 

(mg/L/day) 

Inhalation (mist/dust) 

(mg/L/day) 

<50 

<100 

<1 

<0.1 

50-250 

100-500 

1-2.5 

0.1-0.5 

>250 

>500 

>2.5 

>0.5 

Developmental Toxicity 

Oral (mg/kg/day) 

Dermal (mg/kg/day) 

Inhalation (gas/vapor) 

(mg/L/day) 

Inhalation (mist/dust) 

(mg/L/day)

<50 

<100 

<1.0 

<0.1 

50 – 250 

100 – 500 

1.0 – 2.5 

0.1 – 0.5 

>250 

>500 

>2.5 

>0.5 

 Neurotoxicity

Oral (mg/kg-bw/day) 90-

day (13 weeks) 

40-50 days 

28-days (4 weeks) 

Dermal (mg/kg-bw/day) 90-

day (13 weeks) 

40-50 days 

28-days (4 weeks) 

 

< 10 

< 20 

< 30 

< 20 

< 40 

< 60 

10 – 100 

20 – 200 

30 – 300 

20 – 200 

40 – 400 

60 – 600 

> 100 

> 200 

> 300 

> 200 

> 400 

> 600 
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 High Moderate Low Hazard Score 

 Ranking 3 2 1

Chronic Toxicity

Oral (mg/kg-bw/day) 90-

day (13 weeks) 

40-50 days 

28-days (4 weeks) 

Dermal (mg/kg-bw/day) 90-

day (13 weeks) 

40-50 days 

28-days (4 weeks) 

< 10 

< 20 

< 30 

< 20 

< 40 

< 60 

10 – 100 

20 – 200 

30 – 300 

20 – 200 

40 – 400 

60 – 600 

> 100 

> 200 

> 300 

> 200 

> 400 

> 600 

 Respiratory Sensitization GHS 1A and 1B 

Occurrence of 

respiratory 

sensitization; 

Evidence 

supporting 

potential for 

respiratory 

sensitization 

 No evidence to 

support 

potential for 

respiratory 

sensitization 

Acute Aquatic Toxicity 

(LC50 or EC50) (mg/L) 

< 1.0 – 10 > 10 - 100 > 100 

 Chronic Aquatic Toxicity 

(NOEC or LOEC) (mg/L) 

< 0.1 – 1 > 1 - 10 > 10 

Hazard Score 

 Because the highest score from any individual endpoint was taken as the total Hazard Score, a 

chemical was ranked as either 3 (High), 2 (Moderate), or 1 (Low) for hazard. 

 For the toxicity endpoints Acute Mammalian Toxicity, Reproductive Toxicity, Developmental 

Toxicity, Neurotoxicity, and Chronic Toxicity a range of values for each Hazard Level was assigned. 

These values appear in the DfE Alternatives Assessment Criteria. In some cases DfE has 5 distinct 

hazard levels. For this analysis, the “Very High” and “High” levels from DfE were grouped together 

to represent High on this scale and DfE’s “Low” and “Very Low” levels were combined to form the 

criteria for a Low rank. 

 The hazard levels for Carcinogenicity were based on whether a chemical is a known, 

presumed, or suspected carcinogen (High); limited evidence of carcinogenicity (Moderate); or noncarcinogenetic (Low). Note that the High score for carcinogenicity in Step 2 is broader than the 

criteria used in the Step 1 for carcinogenicity. The Step 1 factor specified that a chemical be 

classified as a known or probable carcinogen, equivalent to the GHS 1A or 1B classification, in order 

to be included in the screening program expressly on the basis of carcinogenicity. For the purpose of 

further evaluating the Agency’s potential concern for chemical hazard in Step 2 of this screening 

process, however, EPA included presumed, suspected, or likely human carcinogenicity classifications 

– the equivalent of GHS 2 – as also meriting a High hazard score. 
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 The hazard levels for Mutagenicity/Genotoxicity were based on evidence that heritable 

mutations are known to or may occur in human germ cells, or mutagenicity demonstrated in vivo and 

in vitro (High); evidence of mutagenicity supported by in vivo or in vitro somatic cells of humans and 

animals (Moderate); or no evidence of chromosomal aberrations and gene mutations in reported 

studies (Low). 

 Respiratory Sensitization was based on GHS classifications of respiratory sensitizers. Hazard 

levels were based on whether there is occurrence of respiratory sensitization in humans or supporting 

evidence based on other tests, including the presence of structural alerts (High); or no evidence to 

support the potential for respiratory sensitization (Low). This endpoint was added to the prioritization 

template proposed in the August 2011 Discussion Guide following stakeholder comment that 

respiratory sensitization is particularly of interest to children’s health issues based on the increasing 

trends of childhood asthma and other illnesses. 

Environmental toxicity information was limited primarily to aquatic toxicity studies. If 

information about environmental toxicity was available, it was analyzed in conjunction with human 

toxicity information. 

Chemicals that were scored as High for hazard only on the basis of acute mammalian toxicity 

were further considered on the basis of their classification for other human health endpoints. Where 

data on other health endpoints were available, the overall hazard score for the chemical was adjusted 

accordingly to reflect the highest remaining health endpoint. This was done because chemicals with 

high acute mammalian toxicity are generally already regulated on the basis of that toxicity and are 

subject to handling and use controls intended to protect workers and others potentially coming into 

contact with the chemical from harmful acute exposures. Scoring those chemicals on the basis of 

their other toxic effects was intended to acknowledge that protection against effects from acute 

exposures would not necessarily protect against effects from other exposures. If acute mammalian 

toxicity was the only available data endpoint for a chemical, the acute score remained as the overall 

hazard score for the chemical. 

Chemicals that scored as High for hazard only on the basis of acute or chronic aquatic toxicity 

but that did not present human health concerns were grouped separately as being of potential concern 

for the environment. 

If no hazard data were available on a chemical to provide a hazard score, the chemical was 

placed in a parallel prioritization category. These chemicals were classified as “Potential Candidates 

for Information Gathering.” (See page 16.) Creating a separate category ensured that chemicals with 

unknown toxicity would not be removed from further investigation because there was a lack of data. 

Exposure Score: 

The Exposure Score was based on a combination of chemical use, general population and 

environmental exposure, and release information. The Use Type score included consideration of 

consumer product applications as well as industrial and commercial uses that could result in 

widespread exposures. The General Population and Environmental Exposure score encompassed 

measured data on the presence of a chemical in biota and environmental media. The Release score 

was based on EPA’s Toxics Release Inventory (TRI) data for chemicals subject to TRI reporting. For 
U.S. Environmental Protection Agency February 2012

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non-TRI chemicals, the Release score was calculated using a method involving Inventory Update 

Reporting data (IUR, now called Chemical Data Reporting, or CDR), including production volume, 

number of sites, and type of use. Data used in the other two components of exposure scoring were 

obtained through the sources identified in Appendix B. The detailed description of how information 

from those sources was used to generate an exposure score appears in Appendix C. 

 Table 2. Exposure Score 

 Score 

I. Use Type 

Ranking Criteria Use Score 

3 Consumer product widely used, high 

likelihood of exposure 

2 Consumer product narrow use, lower 

likelihood of exposure 

1 Commercial use, indicating some likelihood of 

exposure 

0 No reported commercial use, indicating little to 

no likelihood of general exposure from use 

 

II. General Population and Environmental Exposure

Ranking Criteria + General Population 

& Environmental 

Exposure 

3 Present in biota (human, fish, animal or plant 

biomonitoring), OR measured in drinking 

water, indoor air, house dust 

2 Not in biota, but reported present in 2 or more 

environmental media 

1 Reported present in 1 environmental medium 

 III. Release Score: Use III. A or III. B, As Appropriate 

III. A. Release Score for TRI Chemicals* + TRI Release Score 

Ranking Criteria 

3 > 100,000 lbs/year 

2 5,000 – 100,000 lbs/year 

1 < 5,000 lbs/year 

OR OR 

III. B. Release Score for Non-TRI Chemicals + Non-TRI Release 

Score 
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The III.B. Release Score for Non-TRI Chemicals was generated by normalizing the sum 

of the subset rankings for Production Volume, Number of Sites, Industrial Processing and Use, 

and Commercial/Consumer Use differentiating between uses with high, moderate, and low potential 

for widespread releases, as shown below and described in detail in Appendix C: 

Subset 1: IUR Production Volume PV 

Ranking Criteria 

3 ≥ 1,000,000 lbs/year 

2 ≥ 500,000 – 999,999 lbs/year 

1 < 500,000 lbs/year 

Subset 2: IUR Number of Manufacturing, 

Processing, and Use Sites + Site # 

Ranking Criteria 

3 ≥ 1, 000 

2 100 – 999 

1 < 100 

Subset 3: IUR Industrial Processing and 

Use (IPU) 

+ Use1 

Ranking Criteria 

3 High potential for release 

2 Moderate potential for release 

1 Low potential for release 

Subset 4: IUR Commercial Use (C) +Use2 

Ranking Criteria 

3 High potential for release 

2 Moderate potential for releases 

1 Low potential for release 

Subtotal Surrogate Score = 

Total Exposure Score** 

* TRI data included in the exposure calculation were limited to water, air, and non-contained land releases. 

** Total Exposure Score is the sum of the individual scores for I, II, and III.A or III.B. 

The criteria for exposure potential in the Use Types category were based on a chemical’s 

presence and characteristics of use in consumer, commercial, or industrial products as indicated in the 

data sources in Appendix B. Chemicals in consumer products judged widely used with a high 

potential for exposure received the highest rank. Chemicals that are present in consumer products but 

are more narrowly used and have lower likelihood of exposure were ranked as moderate. Chemicals 

that are not high or moderate but have commercial uses reported in IUR were ranked as low, 

acknowledging that such uses may present some potential for exposures not only to workers but also 

to the general population and the environment. Chemicals with no commercial use reported in IUR 
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received a rank of zero. Further information on this approach and examples of ranking by use type 

are provided in Appendix C. 

The data supporting ranking in the General Population and Environmental Exposure category 

came from the databases and peer-reviewed studies included in the list presented in Appendix B. The 

highest rank was based on presence in biota, because chemicals measured in humans, fish, animals, 

or plants demonstrate clear evidence of exposure; and on measured presence in indoor air, house dust, 

or drinking water, because presence in those specific media provides a strong indication of exposure 

potential. Presence in two or more environmental media indicates a reasonable potential for 

environmental exposure, which was the criteria for a moderate exposure ranking. Measured presence 

in one environmental medium provides some indication of potential environmental exposure, and was 

given a low ranking. 

The Release Score was determined in one of two ways. If the chemical was reported under 

TRI, the TRI data were used to infer potential for environmental and general population exposure. 

The breakdowns for the high, moderate and low ranks were based on a distribution of pounds 

released for the chemicals reported by industry in the database. 

If no TRI data existed, a release score was calculated on the basis of IUR data using 

production volume, number of sites, and use codes classified according to how likely the uses were to 

result in releases. The description of how these non-TRI release scores were derived, along with 

examples of how IUR use codes were associated by EPA with high, moderate, or low potentials for 

release, appears in Appendix C. While a chemical’s production volume, use type, and number of 

manufacturing, processing, and industrial use sites do not provide exposure data, they can be used as 

an indicator of potential releases and resulting potential exposures. 

All Exposure category scores were added up and then normalized on an overall HighModerate-Low scale. To prevent the prioritization process from being biased unduly either toward or 

against data-rich chemicals, the normalization process differed depending on how many of the three 

categories – Use Type, General Population & Environmental Exposure, and Releases – had sufficient 

data to provide a score for the category. 

For chemicals with scores in all three categories, “9” was the highest possible score, and the 

normalization scoring structure was: 

Total Exposure Score 

from Table 2 

Overall Rank Normalized Overall 

Exposure Score 

8 - 9 High 3 

5 - 7 Moderate 2 

2 - 4 Low 1 

 
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 For chemicals with scores in only two of the three categories, “6” was the highest possible 

score, and the normalization scoring structure was: 

Total Exposure Score 

from Table 2 

Overall Rank Normalized Overall 

Exposure Score 

5 - 6 High 3 

3 - 4 Moderate 2 

1-2 Low 1 

In the absence of exposure data on chemicals sufficient to populate at least two of the 

exposure categories in Table 2 and produce a meaningful score, such chemicals receiving moderate 

or high hazard scores, or that also could not be scored for hazard because of an absence of hazard 

data, were placed in a parallel prioritization category. These chemicals were classified as “Potential 

Candidates for Information Gathering.” (See page 16.) EPA created this separate category to ensure 

that chemicals with unknown toxicity or with known potential human health or environmental 

toxicity implications would not be removed from further investigation simply because there was a 

lack of exposure information, an issue stakeholders identified during the webinar and discussion 

forum as being of concern. 

Potential for Persistence/Bioaccumulation:

 Chemicals received a separate score to rank their potential for persistence and/or 

bioaccumulation. Persistent and bioaccumulative chemicals present special issues because organisms 

can remain exposed to them for a very long time and organisms higher up the food chain may be 

exposed to larger quantities of the chemicals through their food supply. EPA considers it particularly 

important that these chemicals not be removed from consideration for further investigation simply 

because they may lack either hazard or exposure information, or both. 

Persistence scoring consisted of the evaluation of the potential half-life in air, water, soil, and 

sediment while considering the expected partitioning characteristics of the chemicals and all 

potential removal pathways based on standard physical-chemical properties and environmental 

fate parameters. Data sources listed in Appendix B were searched to locate studies on biotic and 

abiotic transformation (e.g., biodegradation, hydrolysis, photolysis) in order to estimate half-lives for 

the chemicals in the environment. 

Bioaccumulation scoring consisted of evaluation of bioaccumulation/bioconcentration 

(measured or estimated BAF/BCF) data. When BAF data were not available, bioconcentration data 

(measured or estimated) were used to evaluate the potential for a chemical to bioaccumulate in 

organisms in the environment. 

 In the absence of test data establishing the chemical’s measured persistence or 

bioaccumulation potential, EPA used EPI SuiteTM version 4.10 to derive a ranking for the chemical. 

Specifically, BIOWIN, HYDROWIN, AOPWIN, BCF/BAF and Level III fugacity models were used 

to assess biodegradation, hydrolysis, atmospheric oxidation, bioaccumulation/bioconcentration and 

environmental partitioning. 
U.S. Environmental Protection Agency February 2012

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 Table 5. Persistence/Bioaccumulation Potential 

 Overall Persistence/ 

Bioaccumulation Score 

I. Persistence 

Ranking Criteria 

Persistence 3 Half-life > 6 months 

2 Half-life ≥ 2 months 

1 Half-life < 2 months 

 

II. Bioaccumulative Potential 

Ranking Criteria 

+ Bioaccumulation 3 BCF or BAF > 5000 

2 BCF or BAF ≥ 1000 

1 < 1000 

 

Total Persistence/ 

Bioaccumulation Score 

 These criteria for judging persistence and bioaccumulation are the ones used in EPA’s New 

Chemicals program. The separate scores for persistence and bioaccumulation were added together to 

produce a total score, which was normalized as follows: 

Persistence/Bioaccumulation Score Ranking Normalized P/B Score 

5 - 6 High 3 

3 - 4 Moderate 2 

2 Low 1 

 

Categorizing Candidates for Inclusion as TSCA Work Plan Chemicals

 After the candidate chemicals in Step 1 received normalized scores for Hazard, Exposure, and 

Persistence/Bioaccumulation, those scores were totaled to roughly group the chemicals receiving 

scores in all three categories into High, Moderate, and Low groupings as follows: 

Normalized Total Score Ranking 

7 - 9 High 

4 - 6 Moderate 

1 - 3 Low 

 Appendix D identifies the 83 candidate chemicals from Step 1 that received scores on all three 

ranking factors and ranked High on the basis of their total score, including human health hazard 

concerns, and provides a brief summary of the information that produced that ranking. This table also 

includes chemicals that may not have presented human health concerns, but met all the criteria for 

identification as persistent, bioaccumulative, and environmentally toxic chemicals. These are the 

TSCA Work Plan Chemicals, from which the Agency intends to select chemicals for near-term 

review and assessment. 
U.S. Environmental Protection Agency February 2012

16 

 EPA notes that some chemicals identified as High through this scoring system may not 

necessarily be practical candidates for assessment under TSCA when other information is factored 

into the process. For example, the particular risks presented by certain chemicals may already be 

addressed by significant regulation under other statutes. One such example is quartz, which presents a 

hazard only in the context of silicosis from the inhalation of very fine crystalline dust particles, which 

could generally occur only during such occupational activities as sandblasting or stone cutting; these 

potential exposures are specifically controlled under regulations issued by the Occupational Safety 

and Health Administration (OSHA). 

Potential Candidates for Information Gathering 

 Chemicals that could not be scored for hazard, or that were scored as moderate or high for 

either hazard or for persistence/bioaccumulation but could not be scored for exposure, have been 

grouped separately. These chemicals may be potential candidates for information-gathering activities 

focused on producing sufficient information to determine where they would rank in the prioritization 

process. EPA may consider a variety of such information-gathering activities, including both 

voluntary data submission and regulations issued under Sections 4 and 8 of TSCA. 

Identifying Work Plan Chemicals for Risk Assessment in 2012 and Beyond

 In identifying a smaller set of chemicals for work in any given year, EPA considers a number 

of factors, including: 

 Whether the chemical was identified as a “High” ranking chemical. 

 Whether the chemical reflects more than one of the factors identified in Step 1 (for 

example, chemicals that were identified as a potential concern for children’s health and 

also were persistent, bioaccumulative, and toxic) and whether each of the factors was 

covered by the set of chemicals. These factors included health and environmental 

hazards, children’s health, use in consumer products and dispersive uses, persistence and 

bioaccumulation, and detection in biomonitoring and environmental monitoring. 

 Whether certain chemicals, or groups of chemicals, would benefit from some preliminary 

work to assure that risk assessments are targeted and scoped appropriately, and therefore 

would best be addressed in an out year. 

 Whether certain chemicals, or groups of chemicals, have previously been assessed and 

addressed by the Agency, so that risk assessment in later years may be more appropriate 

than in the earlier years of the work plan. 

 Agency work load considerations, including scope and timing of work needed on 

specific chemicals, and existing commitments for assessment. 

 For 2012, EPA identified an initial group of seven chemicals, which can be found on the first 

page of the table in Appendix D. EPA will identify a group of chemicals each year for risk 

assessment, completing a number of risk assessments that year and initiating new assessments from 
U.S. Environmental Protection Agency February 2012

17 

the remaining chemicals on the work plan in the coming years. This spring, the Agency plans to 

identify specific chemicals for which it plans to conduct risk assessment in 2013 and 2014.
U.S. Environmental Protection Agency February 2012

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APPENDIX A: Data Sources for Hazard Scoring

Data Sources for Hazard Scoring 

 Hazard Information (Data on all toxicological endpoints) 

Providers/ Data 

Source Description 

USEPA: IRIS Integrated Risk Information System (IRIS): 

http://www.epa.gov/iris/index.html 

USEPA: HPVIS 

Hazard Characterizations prepared by EPA on chemicals in the High 

Production Volume Challenge Program (HPV): 

http://iaspub.epa.gov/oppthpv/hpv_hc_characterization.get_report?doctype=2

Risk-Based or Hazard-Based Prioritizations prepared by EPA under the 

Chemical Assessment and Management Program (ChAMP): 

http://iaspub.epa.gov/oppthpv/existchem_hpv_prioritizations.report 

USEPA: ISIS 

The Integrated Scientific Information System (ISIS) is a chemical relational 

database application originally developed by Molecular Design Limited 

(MDL) Information Systems and utilized by the EPA New Chemicals 

program; the EPA version of this database contains confidential information. 

United Nations 

World Health 

Organization: IARC 

International Agency for Research on Cancer (IARC): 

http://monographs.iarc.fr/ENG/Classification/index.php 

National Toxicology 

Program 

NTP Report on Carcinogens: http://ntp.niehs.nih.gov/?objectid=03C9AF75-

E1BF-FF40-DBA9EC0928DF8B15 

NTP/CERHR Monographs on Potential Reproductive and Developmental 

Effects: http://ntp.niehs.nih.gov/?objectid=974B2C24-030F-D308-

60E11D088F83FADB 

Organization for 

Economic 

Cooperation and 

Development 

(OECD): eChem 

Portal 

http://www.echemportal.org/echemportal/substancesearch/page.action?pageI

D=0 

The OECD eChemPortal allows simultaneous searching of reports and 

datasets by chemical name and number and by chemical property. Direct links 

to collections of chemical hazard and risk information prepared for 

government chemical review programs at national, regional and international 

levels are obtained. Classification results according to national/regional 

hazard classification schemes or to the Globally Harmonized System of 

Classification and Labelling of Chemicals (GHS) are provided when 

available. The list of participating databases can be accessed here: 

http://www.echemportal.org/echemportal/substancesearch/page.action;jsessio

nid=1AB4C820B2D854B7FB9381877022B9F6?pageID=2 
U.S. Environmental Protection Agency February 2012

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 Hazard Information (Data on all toxicological endpoints) 

Providers/ Data 

Source Description 

National Library of 

Medicine Databases 

http://chem.sis.nlm.nih.gov/chemidplus/chemidheavy.jsp 

Accessed through ChemID Plus, searching on a chemical name or ID 

produces results that are linked to all NLM databases, including: 

Registry of Toxic Effects of Chemical Substances (RTECS) 

ATSDR Public Health Statements 

ATSDR Toxicological Profiles 

ATSDR ToxFAQS 

TSCATS The Toxic Substance Control Act Test Submission Database 

http://www.syrres.com/esc/tscats.htm

California Office of 

Environmental 

Health Hazard 

Assessment 

Risk assessment documents prepared by OEHHA on certain Proposition 65 

chemicals can be accessed through the links provided in the spreadsheet at: 

http://oehha.ca.gov/prop65/prop65_list/files/P65list110411links.xlsx 

USEPA - Ambient 

Water Quality 

Criteria Documents 

http://www.epa.gov/waterscience/criteria/wqcriteria.html

USEPA - Drinking 

Water Standards 

Health Effects 

Support Documents 

http://www.epa.gov/safewater/standards.html

USEPA - ECOTOX 

Database http://www.epa.gov/ecotox

IPCS Concise 

International 

Chemical 

Assessment 

Documents 

(CICADs) 

http://www.inchem.org/pages/cicads.html

 
U.S. Environmental Protection Agency February 2012

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APPENDIX B: Data Sources for Exposure Scoring

Data Sources for Exposure, Uses, and Environmental Fate (P and B) Scoring 

Data Type Data Source 

Uses 

Inventory Update Reporting and Chemical Data Reporting (IUR/CDR)

Premanufacture Notice (PMN) Database (confidential) 

Design for the Environment chemicals database (confidential) 

High Production Volume (HPV) Challenge Submissions

EPA Hazard Characterizations and Risk Based Prioritizations

OECD Screening Information Assessment Profiles and Reports 

Screening Information Data Sets (SIDS) Documents

National Institutes of Health (NIH) Household Product Database

NLM Hazardous Substances Data Bank

NLM- Hazmap-Occupational exposure to hazardous agents 

Source Ranking Database 

Chemical assessments by other governmental organizations 

Open literature 

Environmental 

releases 

Toxics Release Inventory (TRI)

National Emission Inventory (NEI) Database U.S. EPA 

NIH Hazardous Substances Data Bank

General human 

exposures, 

including indoor 

air contaminants 

National Report on Human Exposure to Environmental Chemicals (CDC 

NHANES) 

Report to the California Legislature Indoor Air Pollution in California.

http://www.arb.ca.gov/research/indoor/ab1173/rpt0705.pdf

German Environmental Survey- chemicals in indoor air 

http://www.umweltbundesamt.de/gesundheite/ 

survey/index.htm 

NLM Hazardous Substances Data Bank

Open Literature

Environmental 

exposures 

National Air Quality System (AQS) U.S. EPA

National Contaminant Occurrence Database (NCOD) U.S. EPA

Current National Recommended Water Quality Criteria U.S. EPA

National Water-Quality Assessment Program (USGS NAWQA)

EPA Fish Tissue Studies

Clean Air Act Hazardous Air Pollutants (HAPs) 

Clean Water Act Priority Pollutants 

Superfund Chemical Data Matrix 

EPA: Targeted National Sewage Sludge Survey Report 

Groundwater chemicals Desk reference Chemicals in Groundwater Desk 

reference 2007 

EPA Drinking water Chemical contaminant lists 

New York State Ambient Air monitoring program 

California Air Resources Board (ambient air) 

Washington State Background Soil concentration study 

NLM Hazardous Substances Data Bank

Open literature 
U.S. Environmental Protection Agency February 2012

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Data Type Data Source 

Environmental 

Fate 

(Persistence and 

Bioaccumulation) 

USEPA: HPVIS Hazard Characterizations prepared by EPA on chemicals in the 

High Production Volume Challenge Program (HPV): 

http://iaspub.epa.gov/oppthpv/hpv_hc_characterization.get_report?doctype=2 

Risk-Based or Hazard-Based Prioritizations prepared by EPA under the 

Chemical Assessment and Management Program (ChAMP): 

http://iaspub.epa.gov/oppthpv/existchem_hpv_prioritizations.report

Organization for Economic Cooperation and Development (OECD): eChem 

Portal 

http://www.echemportal.org/echemportal/substancesearch/page.action?pageID=

0

http://www.echemportal.org/echemportal/substancesearch/page.action;jsessioni

d=1AB4C820B2D854B7FB9381877022B9F6?pageID=2

SRC Environmental Fate Databases 

http://www.srcinc.com/what-we-do/efdb.aspx

National Library of Medicine Hazardous Substances Databank 

http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB

Japanese National Institute of Technology and Evaluation (NITE). 

Biodegradation and Bioconcentration of the Existing Chemical Substances 

under the Chemical Substances Control Law NITE 

http://www.safe.nite.go.jp/english/kizon/KIZON_start_hazkizon.html

 
U.S. Environmental Protection Agency February 2012

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APPENDIX C: Derivation of Exposure Scores for Use Types 

 and Release Scores for TRI and Non-TRI Chemicals

Criteria I: Use Type 

A variety of use information was reviewed to determine whether chemicals were used for 

consumer, commercial, or industrial purposes. At least two data sources were used to confirm 

consumer uses. For example, a reported use in EPA’s IUR alone was not deemed sufficient to 

identify a chemical as being in a consumer product. Also note that many chemicals are present in 

several different product use and functional use categories. All reported uses were considered, and 

the use with the highest exposure potential informed the prioritization ranking. See Appendix B for 

additional information on data sources. 

Chemicals that were given a rank of three are believed to be present in consumer products and 

have high potential for exposure due to widespread uses. Chemicals that received a high score have 

higher potential for exposure due to high likelihood of releases from the product (off-gassing) and 

high potential for direct contact during application or use based on close proximity. Examples of 

product criteria that have an increased likelihood of exposure include: products that are not fully 

cured (chemical reaction is occurring on-site); products that are spray-applied or brush-applied; 

products that are liquids, gases, or otherwise have the potential to volatilize; products that have the 

potential to off-gas, degrade, or otherwise emit chemicals over time; and products that have the 

potential to be incorrectly applied or used also received a rank of three. Some organizations may 

identify higher exposure potential uses as being dispersive. Examples of product use categories that 

have this increased likelihood of exposure include: paints and coatings; adhesives, sealants, and 

elastomers; building materials such as insulation; soaps and detergents; hair care products; water 

treatment products; floor coverings; automotive care products; and arts, crafts, and hobby materials. 

Chemicals that were given a rank of two had moderate exposure. Chemicals that received a 

moderate score have moderate potential for exposure because they may be present within a 

chemically stable matrix; have lower or slower likelihood of release from the product, and have more 

indirect or bystander exposure. There may be increased distance and time between product sources 

and individual receptors. These chemicals may slowly off-gas or partition to dust over time. 

Examples of product use categories include: plastic and rubber products, electronics products, 

furniture, and foam seating and bedding products. 

Chemicals were given a rank of one if at least one commercial use for that chemical was 

reported in IUR. 

Chemicals that were not reported in IUR or were reported in IUR with industrial uses but no 

commercial or consumer uses were given a rank of zero for the use type criterion of exposure. 

Criteria II: General & Environmental Exposure 

A variety of data sources were used to compile information on chemicals present within the 

environment: ambient air, surface water, groundwater, drinking water, soil, indoor environments (air 

or dust), and chemicals present within biota (humans, fish, animals, or plants). Only a small 

percentage of all chemicals are actually measured for in various media for reasons such as a lack of 
U.S. Environmental Protection Agency February 2012

23 

adequate sampling and analytical methods and insufficient resources to collect data. Many of the 

chemicals identified were not able to be ranked for this criterion due to lack of data. 

 A summary of the number of chemicals identified in different media is provided below. Note 

that this compilation of chemicals is an initial effort based on readily available and publicly 

accessible data. It is not a complete or comprehensive assessment of number of chemicals present in 

any given environmental or biological media. Approximately two-thirds of these chemicals are on the 

TSCA inventory while the other one-third is not. Refer to Appendix B for additional information on 

data sources for each media. 

Number of Chemicals Reported in Environmental Media 

Occurrence of chemicals (by media) Number of chemicals 

Surface water 401 

Ground water 407 

Ambient air 409 

Soil 270 

Indoor environments 300 

Drinking water 247 

Biota 360 

Total 1215 

Criteria III: Release Score 

III. A. Release Scores for TRI Chemicals

 The release score for each chemical was determined using the aggregated releases from the 

TRI data fields listed in the following table. The 2008 TRI database was used for the chemical 

ranking scheme. A ranking of 3 was assigned for a sum of releases greater than 100,000 lb/yr, a 

ranking of 2 for a sum of releases greater than 5,000 lb but less than or equal to 100,000 lb/year, and 

a ranking of 1 for a sum of releases less than 5,000 lb/yr. 

2008 TRI Data Fields for Release Score 

TRI Data Field 

Total Fugitive Air Emissions Wastewater Treatment (Excluding POTWs) 

Total Stack Air Emissions Landfills/Disposal Surface Impoundments 

Total Surface Water Discharge Surface Impoundment 

Total Other On-Site Land Releases (Other Landfills) Other Landfills 

Total Land Treatment Land Treatment 

Total Surface Impoundments Other Land Disposal 

Total Other Disposal Unknown 

POTWs - Total Transfers - Metals Only RCRA Subtitle C Surface Impoundments (M66) 

Transfers To POTWs (Non-Metals) Other Surface Impoundments (M67) 

Transfers To POTWs (Metals And Metal 

Compounds) 
U.S. Environmental Protection Agency February 2012

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III. B. Release Scores for Non-TRI Chemicals

For chemicals not reported to TRI, 2006 IUR data were used to rank chemicals for potential to 

be released to the environment. The release ranking was derived based on at least three of the 

following four factors: (1) IUR Production Volume Ranking; (2) IUR Number of Manufacturing, 

Processing, and Use Sites Ranking; (3) IUR Industrial and Downstream Processing and Use Ranking; 

and (4) IUR Commercial/Consumer Use Rankings. 

Production Volume and Number of Sites Rankings

For the production volume ranking, data from the non-CBI public IUR database were used to 

rank chemicals using the following cut-offs: greater than or equal to 1,000,000 lb/year for a high 

ranking of 3; less than 1,000,000 and greater than or equal to 500,000 lb/year for a medium ranking 

of 2; and less than 500,000 lb/year for a low ranking of 1. 

The number of industrial sites ranking, data on manufacturing, processing, and use sites in 

non-CBI public IUR database were used to rank chemicals using the following cut-offs: greater than 

or equal to 1,000 sites for a high ranking of 3; less than 1,000 and greater than or equal to 99 sites for 

a medium ranking of 2; and less than 100 sites for a low ranking of 1. 

Industrial Processing and Use (IPU) Ranking

For the industrial processing and use ranking, EPA examined the following codes reported 

under IUR for each chemicals (see the table of sample categories, below): North American Industrial 

Classification System (NAICS) code, Process or Use code, and the Industrial Function Category. 

Each 3-code combination was assigned a ranking (high/moderate/low) based on the potential to be 

released during the industrial processing/use and downstream use. The Agency ranked each 3-code 

combination using expert judgment, generic scenarios, and past experience with new and existing 

chemical assessment. The 3-code combination with highest ranking was used as the score for the IPU 

ranking for the chemical. 

The resulting industrial rankings were modified based on whether the chemical was reported 

as site-limited by all IUR submitters of that chemical or whether industrial uses may have been 

required to be reported in IUR. Site-limited chemicals were given an IPU Ranking of 1.

Under the IUR, reporters had an option to indicate if industrial processing and use (IPU) 

information was not applicable to their chemical; if all reporters of a chemical indicated that the 

industrial processing and use information was not applicable, EPA assumed there was no such use 

and assigned a low ranking of 1. For chemicals with an IPU ranking of 1 or 2 that had one or more 

IPUs reported as “NRO,” the rankings were developed based solely on reported IPUs. No ranking 

was developed for chemicals with all IPUs reported as “NRO.” EPA assigned a high ranking of 3 for 

chemicals with at least one reported IPU code with a high potential for widespread releases.
U.S. Environmental Protection Agency February 2012

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Sample of 2006 IUR Industrial Processing and Use Reporting Categories 

Industrial Function Categories Industrial Processing or Use Small Sample of 

NAICS 

Adsorbents and absorbents Processing as a reactant Petrochemical manufacturing 

Adhesives and binding agents Processing – incorporation into 

formulation, mixture or reaction 

product 

Synthetic dye and pigment 

manufacturing 

Aerosol propellants Processing – incorporation into article Other basic inorganic chemical 

manufacturing 

Agricultural chemicals (non-pesticide) Processing – repackaging Resin and synthetic rubber 

manufacturing 

Anti-adhesive agents Use - non-incorporative activities Fertilizer manufacturing 

Bleaching agents Paint and coating manufacturing 

Coloring agents, dyes Printing ink manufacturing 

Coloring agents, pigments Plastics bottle manufacturing 

Corrosion inhibitors and anti-scaling 

agents 

Tire manufacturing 

Fillers Cement manufacturing 

Fixing agents Abrasive product manufacturing 

Flame retardants Ferrous metal foundries 

Flotation agents Electric power generation 

Fuels 

Functional fluids 

Intermediates 

Lubricants 

Odor agents 

Oxidizing agents 

pH-regulating agents 

Photosensitive chemicals 

Plating agents and metal surface treating 

agents 

Processing aid, not otherwise listed 

Process regulators, used in vulcanization 

or polymerization processes 

Process regulators, other than 

polymerization or vulcanization 

processes 

 

Reducing agents 

Solvents (for cleaning or degreasing) 

Solvents (which become part of product 

formulation or mixture) 

Solvents (for chemical manufacture and 

processing and are not part of product at 

greater than one percent by weight) 

 

Stabilizers 

Surface active agents 

Viscosity adjustors 

Other 
U.S. Environmental Protection Agency February 2012

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Commercial Use (C) Release Ranking

For the commercial use ranking, EPA examined each IUR Commercial Use Code reported for 

the chemicals and assigned a ranking based on their potential to be released during use. For the 

purpose of this screening exercise, it was assumed that all the “C” use codes in the 2006 IUR 

included commercial uses. The Agency used past experience in new and existing chemical 

assessments of similar chemicals and exposure scenarios, coupled with expert judgment, to examine 

each use to place the chemical in a high, moderate, or low ranking. The use code with the highest 

ranking was used as the score for the commercial use ranking for the chemical. 

The following table lists samples of rankings associated with certain uses. Commercial uses 

considered likely to result in air and/or water releases were assigned a high ranking score of 3. Uses 

with low or no potential for releases were given a low score of 1. The rest of the uses were given a 

score of 2. 

Under the IUR, reporters had an option to indicate if commercial/consumer information was 

not applicable to their chemical. If all reporters of a chemical indicated that the commercial/consumer 

information was not applicable, EPA assumed there was no commercial use of the chemical, resulting 

in a low ranking (i.e., score of 1). For chemicals with a ranking of 1 or 2 that had one or more 

commercial/consumer uses reported as “not readily obtainable” (NRO) or “Others,” rankings were 

developed based solely on the remaining reported uses. No ranking was developed for chemicals with 

all commercial/consumer uses reported as “NRO” Or “Others.” EPA assigned a High ranking of 3 for 

chemicals with at least one reported C code with a high potential for widespread releases. If multiple 

uses were reported, EPA referred to the use code that resulted in the highest ranking. 

2006 IUR Commercial Use Categories 

2006 IUR Commercial Use 

C01 Adhesives and sealants 

C02 Agricultural products (non-pesticide) 

C03 Artists’ supplies 

C04 Automotive care products 

C05 Electrical and electronic products 

C06 Fabrics, textiles and apparel 

C07 Glass and ceramic products 

C08 Lawn and garden products (non-pesticide) 

C09 Leather products 

C10 Lubricants, greases and fuel additives 

C11 Metal products 

C12 Paints and coatings 

C13 Paper products 

C14 Photographic supplies 

C15 Polishes and sanitation goods 

C16 Rubber and plastic products 

C17 Soaps and detergents 

C18 Transportation products 

C19 Wood and wood furniture 
U.S. Environmental Protection Agency February 2012

27 

Scoring Releases for Non-TRI Chemicals

 The four ranking scores described above – Production Volume (PV), Number of Sites, 

Industrial Processing and Use (IPU) ranking, and Commercial Use (C) ranking – were added to 

develop the release score for non-TRI chemicals. When either IPU or C could not be scored, but all 

the other factors could be scored, the release score was derived based on the remaining three ranking 

scores. If neither the IPU nor the C codes could be scored, no release score was assigned to the 

chemical. 

 When all four sub-scores were available, the possible total score ranged from 4 to 12, and the 

non-TRI Release scores were ranked as follows: 

High (3) = 9 - 12 

Moderate (2) = 7 - 8 

Low (1) = 4 - 6 

 When only three out of the four sub-scores were available (if either IPU or C could not be 

scored), the possible total score ranged from 3 to 9, and the non-TRI Release scores were ranked as 

follows: 

High (3) = 7 - 9 

Moderate (2) = 5 - 6 

Low (1) = 3 – 4 

 The Non-TRI Release score for each chemical was added to the other exposure component 

scores to derive the Total Exposure Score, as described in the body of this paper. 

 
U.S. Environmental Protection Agency February 2012

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APPENDIX D: The TSCA Work Plan Chemicals 
U.S. Environmental Protection Agency 

TSCA Work Plan Chemicals 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

2012 Work Plan Chemicals 

Antimony & Antimony Compounds

Possible human carcinogenDevelopmental and reproductive toxicityAcute and chronic toxicity from inhalation exposures

3 Widely used in consumer products

Present in biomonitoring, drinking water, surface water, ambient air and soilHigh reported releases to the environment 

3 High environmental 

persistence Moderate bioaccumulation potential

3 

1,3,4,6,7,8-Hexahydro4,6,6,7,8,8,-hexamethylcyclopenta [g]-2-benzopyran (HHCB)

Developmental toxicity 2 Widely used in consumer products

Present in biomonitoringEstimated to have high releases to the environment

3 Moderate environmental 

persistence Moderate bioaccumulation potential

2 

Long-chain chlorinated paraffins (C18-20)

Chronic toxicity to target organs including the liver, kidneys and thyroidAquatic toxicity

2 Used in commercial/industrial products

Present in biomonitoring, surface water and soil

2 High environmental 

persistenceHigh bioaccumulation potential 

3 

Medium-chain chlorinated paraffins (C14-17)

Chronic toxicity to target organs including the liver, kidneys and thyroidAquatic toxicity

2 Used in consumer products

Estimated to have high releases to the environment 

2 High environmental 

persistenceHigh bioaccumulation potential

3 

Methylene chloride Probable human carcinogen 3 Widely used in consumer products

Present in drinking water, indoor environments, ambient air, groundwater and soilHigh reported releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential

1 

N-Methylpyrrolidone Reproductive toxicity 3 Widely used in consumer products

Present in drinking water and indoor environmentsHigh reported releases to the environment 

3 Low environmental 

persistence Low bioaccumulation potential

1 

Trichloroethylene (TCE)

Probable human carcinogen 3 Widely used in consumer products

Present in drinking water, indoor environments, surface water, ambient air, groundwater and soil

3 High environmental 

persistenceLow bioaccumulation potential

2 

The TSCA Work Plan Chemicals Methods Document (39 pp., 264 KB) explains the hazard, exposure, and persistence/bioaccumulation criteria, the data sources use

scored.
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

Additional Work Plan Chemicals (alphabetical order)

Acetaldehyde Possible human carcinogen 3 Used in consumer products

Present in drinking water, indoor environments, ambient air and groundwaterHigh reported releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

Acrylonitrile Probable human carcinogen 3 Widely used in consumer products

Present in indoor environments, surface water, ambient air and groundwaterHigh reported releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

tert-Amyl methyl ether Chronic toxicity

Central nervous system effectsPotential carcinogenicity to specific target organs

2 Widely used in consumer products

Present in drinking water, surface water and ambient airEstimated to have moderate releases to the environment

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

Anthra[2,1,9-def:6,5,10-d'e'f'] diisoquinoline-1,3,8,10(2H,9H)-tetrone (Pigment Violet 29)

Aquatic toxicity 3* Widely used in consumer products

Estimated to have moderate releases to the environment

3 High environmental 

persistenceLow bioaccumulation potential 

2 

Arsenic & Arsenic Compounds Known human carcinogen

NeurotoxicityCentral nervous system effectsAcute and chronic toxicity from inhalation exposures

3 Widely used in consumer products

Present in biomonitoring, drinking water, surface water, ambient air and soilHigh reported releases to the environment

3 High environmental 

persistenceLow bioaccumulation potential 

2 

Asbestos & Asbestos-like Fibers Known human carcinogen

Acute and chronic toxicity from inhalation exposures

3 Widely used in consumer products

Present in indoor environments

3 High environmental 

persistenceLow bioaccumulation potential 

2 

Benzenamine Probable human carcinogen 3 Used in consumer products

Present in ambient air, groundwater and soilHigh reported releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential 

1 
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

Benzene Known human carcinogen 3 Widely used in consumer products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air, groundwater and soilHigh reported releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

Benzo[a]pyrene Known human carcinogen 3 Present in biomonitoring, drinking 

water, indoor environments, surface water, ambient air, groundwater and soil

2 High environmental 

persistenceModerate bioaccumulation potential 

3 

Benzo(a)anthracene Probable human carcinogen 3 Present in biomonitoring, indoor 

environments, surface water, ambient air, groundwater and soil

2 High environmental 

persistenceModerate bioaccumulation potential 

3 

1-Bromopropane Possible human carcinogen 3 Widely used in consumer products

Present in drinking water, indoor environments, surface water, ambient air, groundwater and soil Estimated to have high releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

Butanamide, 2,2'-[(3,3'-dichloro[1,1'- biphenyl]-4,4'-diyl)bis(azo)]bis[N-(4-chloro-2,5 -dimethoxyphenyl)-3-oxo- (Pigment Yellow 83)

Acute toxicity 2 Used in consumer products

Estimated to have high releases to the environment

3 High environmental 

persistenceHigh bioaccumulation potential 

3 

Butanamide, 2-[(4-methoxy-2-nitrophenyl) azo]-N-(2-methoxyphenyl)-3-oxo- (Pigment Yellow 65)

Aquatic toxicity 3* Widely used in consumer products

Estimated to have high releases to the environment

3 High environmental 

persistenceLow bioaccumulation potential 

2 

4-sec-Butyl-2,6-di-tertbutylphenol Chronic toxicity 2 Widely used in consumer products Estimated to have moderate releases to 

the environment

3 Moderate environmental 

persistenceModerate bioaccumulation potential 

2 

Cadmium & Cadmium Compounds

Known human carcinogenChronic cardiovascular, renal and musculoskeletal effectsAcute and chronic toxicity from inhalation exposures

3 Widely used in consumer products

Present in biomonitoring, drinking water, surface water, ambient air and soilHigh reported releases to the environment

3 High environmental 

persistenceModerate bioaccumulation potential 

3 
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

Carbon tetrachloride Probable human carcinogen 3 Used in commercial/industrial products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air, groundwater and soilHigh reported releases to the environment 

2 High environmental 

persistenceLow bioaccumulation potential 

2 

p-Chloro-o-toluidine Probable human carcinogen 3 Present in biomonitoring, surface water 

and soil

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

Chromium & Chromium Compounds 

Known human carcinogen Reproductive toxicityDevelopmental toxicityAcute and chronic toxicity from inhalation exposures

3 Used in commercial/industrial products

Present in ambient airHigh reported releases to the environment 

2 High environmental 

persistenceModerate bioaccumulation potential 

3 

Cobalt & Cobalt Compounds Cardiovascular and central 

nervous system effectsAcute and chronic toxicity from inhalation exposures

3 Used in consumer products

Present in biomonitoring, surface water, ambient air and soilHigh reported releases to the environment 

3 High environmental 

persistenceModerate bioaccumulation potential 

3 

Creosotes Probable human carcinogen 3 Widely used in consumer products

Present in groundwater and soilHigh reported releases to the environment

3 Moderate environmental 

persistenceModerate bioaccumulation potential 

2 

Cyanide Compounds (Limited to dissociable compounds) 

NeurotoxicityReproductive toxicityCentral nervous system effects

3 Widely used in consumer products

Present in drinking water, surface water and soilHigh reported releases to the environment 

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

Dibenz(a,h)anthracene Probable human carcinogen 3 Present in indoor environments, surface 

water, ambient air, groundwater and soil

2 Moderate environmental 

persistenceModerate bioaccumulation potential 

2 

Dibromochloromethane Possible human carcinogen 3 Present in biomonitoring, surface water, 

ambient air and soil

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

3,3'-Dichlorobenzidine dihydrochloride 

Probable human carcinogen 3 Used in consumer products

Relatively small reported releases to the environment 

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

1,1-Dichloroethane Mutagenicity 2 Used in consumer products

Present in biomonitoring, drinking water, surface water, ambient air, groundwater and soilModerate reported releases to the environment 

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

1,2-Dichloroethane Possible human carcinogen 3 Used in commercial/industrial products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air, groundwater and soilHigh reported releases to the environment 

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

1,2-Dichloropropane Acute mammalian toxicity 2 Used in consumer products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air, groundwater and soilHigh reported releases to the environment 

3 High environmental 

persistenceLow bioaccumulation potential 

2 

trans-1,2-Dichloroethylene Chronic toxicity 2 Widely used in consumer products

Present in biomonitoring, drinking water, surface water, ambient air, groundwater and soil

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

p-Dichlorobenzene Possible human carcinogen 3 Widely used in consumer products

Present in biomonitoring, drinking water, indoor environments, ambient air, surface water, groundwater and soilModerate reported releases to the environment 

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

o-Dichlorobenzene Chronic toxicity 2 Widely used in consumer products 

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air and groundwaterModerate reported releases to the environment 

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

Dichloroacetic acid Possible human carcinogen 3 Used in consumer products

Present in drinking water

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

1,2-Dimethoxyethane (Monoglyme)

Reproductive toxicityDevelopmental toxicityChronic toxicity

3 Widely used in consumer products

Estimated to have high releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

1,4-Dioxane Possible human carcinogen 3 Widely used in consumer products

Present in groundwater, ambient air and indoor environmentsHigh reported releases to the environment 

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

Ethanone, 1-(1,2,3,4,5,6,7,8-octahydro- 2,3,8,8-tetramethyl-2-naphthalenyl)-

Aquatic toxicity 3* Widely used in consumer products 

Estimated to have high releases to the environment

3 Moderate environmental 

persistenceHigh bioaccumulation potential 

3 

Ethanone, 1-(1,2,3,4,5,6,7,8-octahydro- 2,3,5,5-tetramethyl-2-naphthalenyl)-

Aquatic toxicity 3* Widely used in consumer products 

Estimated to have high releases to the environment

3 Moderate environmental 

persistenceHigh bioaccumulation potential 

3 

Ethanone, 1-(1,2,3,5,6,7,8,8aoctahydro- 2,3,8,8-tetramethyl-2-naphthalenyl)-

Aquatic toxicity 3* Widely used in consumer products 

Estimated to have high releases to the environment

3 Moderate environmental 

persistenceModerate bioaccumulation potential 

2 

Ethanone, 1-(1,2,3,4,6,7,8,8aoctahydro- 2,3,8,8-tetramethyl-2-naphthalenyl)-

Aquatic toxicity 3* Widely used in consumer products 

Estimated to have high releases to the environment

3 Moderate environmental 

persistenceModerate bioaccumulation potential 

2 
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

Ethylbenzene Possible human carcinogen 3 Used in consumer products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air, groundwater and soilHigh reported releases to the environment 

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

Ethylene dibromide Probable human carcinogen 3 Used in commercial/industrial products

Present in drinking water, indoor environments, surface water, ambient air, groundwater and soilRelatively small reported releases to the environment 

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

bis(2-Ethylhexyl) adipate Possible human carcinogen 3 Widely used in consumer products

Present in drinking water and indoor environments Estimated to have high releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

bis(2-Ethylhexyl) -3,4,5,6-tetrabromophthalate (TBPH)

Developmental toxicityAcute and chronic aquatic toxicity 

2 Used in consumer products

Present in indoor environmentsEstimated to have moderate releases to the environment

3 Moderate environmental 

persistenceModerate bioaccumulation potential 

2 

2-Ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB)

Developmental toxicityAcute and chronic aquatic toxicity 

2 Used in consumer products

Present in indoor environments and soil

3 Moderate environmental 

persistenceModerate bioaccumulation potential 

2 

Formaldehyde Known human carcinogen 3 Used in consumer products

Present in indoor environments, drinking water, ambient air and groundwaterHigh reported releases to the environment 

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

Hexabromobiphenyl Possible human carcinogen 3 Used in consumer products

Present in ambient air and soil

2 High environmental 

persistenceHigh bioaccumulation potential 

3 

Hexachlorobutadiene Possible human carcinogen 3 Present in indoor environments, surface 

water, ambient air, groundwater and soilRelatively small reported releases to the environment 

1 High environmental 

persistenceHigh bioaccumulation potential 

3 
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

Hexachlorocyclohexane Possible human carcinogen 3 Present in biomonitoring and surface 

water

2 High environmental 

persistenceModerate bioaccumulation potential 

3 

1-Hexadecanol Chronic toxicity 2 Widely used in consumer products

Present in surface water, ambient air and soilEstimated to have high releases to the environment

3 Low environmental 

persistenceModerate bioaccumulation potential 

2 

Lead & Lead Compounds Neurotoxicity

Developmental toxicityReproductive toxicity 

3 Widely used in consumer products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air and soilHigh reported releases to the environment

3 High environmental 

persistenceModerate bioaccumulation potential 

3 

Mercury & Mercury Compounds Neurotoxicity

Developmental toxicityChronic nervous system and hepatic effects

3 Widely used in consumer products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air and soilHigh reported releases to the environment

3 High environmental 

persistenceModerate bioaccumulation potential 

3 

4,4'-Methylene bis(2-chloroaniline) 

Known human carcinogen 3 Widely used in consumer products

Present in ambient air Relatively small reported releases to the environment 

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

Naphthalene Possible human carcinogen 3 Widely used in consumer products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air, groundwater and soilHigh reported releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

2-Naphthalenecarboxylic acid, 4-[(4-chloro-5-methyl-2-sulfophenyl) azo]-3-hydroxy-, calcium salt (1:1) (Pigment Red 52)

Aquatic toxicity 3* Widely used in consumer products

Estimated to have moderate releases to the environment

3 High environmental 

persistenceLow bioaccumulation potential 

2 
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

Nickel & Nickel Compounds Known human carcinogen

Acute and chronic toxicity from inhalation exposures

3 Used in consumer products

Present in ambient airHigh reported releases to the environment 

2 High environmental 

persistenceLow bioaccumulation potential 

2 

N-Nitrosodiethylamine Probable human carcinogen 3 Present in biomonitoring, surface water, 

and ambient air, groundwater and soilRelatively small reported releases to the environment 

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

N-Nitrosodimethylamine Probable human carcinogen 3 Widely used in consumer products

Present in drinking water, surface water, ambient air, groundwater and soil

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

N-Nitrosodiphenylamine Probable human carcinogen 3 Used in consumer products

Present in surface water, groundwater and soilRelatively small reported releases to the environment 

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

Octamethylcyclotetrasiloxane Reproductive toxicity 2 Used in consumer products

Present in biomonitoring, drinking water, indoor environments and surface waterEstimated to have high releases to the environment

3 Moderate environmental 

persistenceHigh bioaccumulation potential 

3 

4-tert-Octylphenol 4-(1,1,3,3-Tetramethylbutyl)-phenol

Aquatic toxicity 3* Used in consumer products

Present in biomonitoring and drinking waterEstimated to have moderate releases to the environment

3 High environmental 

persistenceModerate bioaccumulation potential 

2 

p,p'-Oxybis(benzenesulfonyl hydrazide)

Reproductive toxicityMutagenicity

3 Used in consumer products

Estimated to have moderate releases to the environment

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

Pentabromophenol Acute toxicity 3 Used in consumer products

Present in surface water and soil

2 High environmental 

persistenceLow bioaccumulation potential 

2 

Phthalic anhydride Respiratory sensitizer 3 Widely used in consumer products

Present in groundwater and ambient airHigh reported releases to the environment

3 Low environmental 

persistenceLow bioaccumulation potential 

1 
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

Polychlorinated naphthalenes Acute dermal toxicity

Chronic liver effects

1 Widely used in consumer products

Present in biomonitoring

3 High environmental 

persistenceHigh bioaccumulation potential 

3 

Quartz (Respirable forms only) Probable human carcinogen 3 Widely used in consumer products

Present in drinking waterEstimated to have high releases to the environment

3 High environmental 

persistenceLow bioaccumulation potential 

2 

Styrene Possible human carcinogen

Central nervous system effects

3 Widely used in consumer products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air, groundwater and soilHigh reported releases to the environment 

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

1,2,4,5-Tetrachlorobenzene Chronic toxicity 3 Present in ground water and soil 1 Moderate environmental 

persistenceHigh bioaccumulation potential 

3 

Tetrachloroethylene (PERC) 

Probable human carcinogen 3 Widely used in consumer products

Present in biomonitoring, drinking water, indoor environments, ambient air, groundwater and soilHigh reported releases to the environment 

3 High environmental 

persistenceLow bioaccumulation potential 

2 

Tribromomethane (Bromoform) Probable human carcinogen 3 Used in consumer products

Present in biomonitoring, drinking water, surface water, ambient air and groundwaterModerate reported releases to the environment 

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

1,1,2-Trichloroethane Possible human carcinogen 3 Widely used in consumer products

Present in biomonitoring, drinking water, surface water, ambient air, and groundwater and soilModerate reported releases to the environment 

3 High environmental 

persistenceLow bioaccumulation potential 

2 

Triglycidyl isocyanurate Reproductive toxicity

MutagenicityAcute toxicity from inhalation exposures

3 Widely used in consumer products

Estimated to have high releases to the environment

3 Moderate environmental 

persistenceLow bioaccumulation potential 

1 
U.S. Environmental Protection Agency 

Chemical Name Hazard Criteria Met 

Hazard 

Score Exposure Criteria Met

Exposure 

Score

Persistence & 

Bioaccumulation Criteria 

Met 

Persisten

Bioaccumu

Score 

2,4,6-Tri-tert-butylphenol Chronic toxicity and liver 

effects

2 Widely used in consumer products

Present in indoor environmentsEstimated to have moderate releases to the environment

3 Moderate environmental 

persistenceHigh bioaccumulation potential 

3 

Tris(2-chloroethyl) phosphate (TCEP)

Mutagenicity Limited evidence of carcinogenicity

2 Widely used in consumer products

Present in drinking water and indoor environments Estimated to have moderate releases to the environment

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

Tris(2,3-dibromopropyl) phosphate (TBP)

Probable human carcinogen 3 Widely used in consumer products

Relatively small reported releases to the environment 

2 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

Vinyl chloride Known human carcinogen 3 Used in consumer products

Present in drinking water, indoor environments, surface water, ambient air, groundwater and soilHigh reported releases to the environment 

3 Moderate environmental 

persistenceLow bioaccumulation potential 

2 

m-Xylene Reproductive toxicity

Developmental toxicity

3 Widely used in consumer products

Present in biomonitoring, drinking water, surface water, ambient air, groundwater and soilHigh reported releases to the environment 

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

o-Xylene Chronic toxicity 3 Used in consumer products

Present in biomonitoring, drinking water, indoor environments, surface water, ambient air, groundwater and soilHigh reported releases to the environment 

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

p-Xylene Reproductive toxicity 3 Widely used in consumer products

Present in biomonitoring, drinking water, surface water, ambient air, groundwater and soilHigh reported releases to the environment 

3 Low environmental 

persistenceLow bioaccumulation potential 

1 

Note: An asterisk (*) in the Hazard Score column indicates the score is based solely on aquatic (environmental) toxicity.