SUPPLEMENTARY INFORMATION:

I. Executive Summary

A. Does this action apply to me?

This action is directed to the public in general and may be of particular interest to those involved in the manufacture (defined under TSCA section 3(9) to include import), processing, distribution, use, and disposal of 1,2-dichloroethane, related industry trade organizations, non-governmental organizations with an interest in human and environmental health, state and local governments, Tribal Nations, and/or those interested in the assessment of risks involving chemical substances and mixtures regulated under TSCA. As such, the Agency has not attempted to describe all the specific entities that this action might apply to. If you need help determining applicability, consult the technical contact listed under FOR FURTHER INFORMATION CONTACT .

B. What is the Agency's authority for taking this action?

The Agency is conducting this risk evaluation under TSCA section 6, 15 U.S.C. 2605, which requires that EPA conduct risk evaluations on chemical substances and identifies the minimum components EPA must include in the risk evaluations. Each risk evaluation must be conducted consistent with the best available science, be based on the weight of scientific evidence, consider reasonably available information, and not consider costs or non-risk factors. 15 U.S.C. 2625(h), (i), and (k). See also the implementing procedural regulations at 40 CFR part 702.

C. What action is the Agency taking?

EPA is announcing the availability of and seeking public comment on a draft risk evaluation under TSCA for 1,2-dichloroethane. The purpose of risk evaluations under TSCA is to determine whether a chemical substance presents an unreasonable risk of injury to health or the environment under the COUs, including unreasonable risk to potentially exposed or susceptible subpopulations identified as relevant to the risk evaluation by EPA, and without consideration of costs or non-risk factors. EPA has used the best available science to prepare this draft risk evaluation and, based on the weight of scientific evidence, to preliminarily ( printed page 52055) determine that 1,2-dichloroethane presents unreasonable risk to human health and the environment driven primarily by certain COUs analyzed in the draft risk evaluation.

D. What should I consider as I prepare my comments?

1. Submitting CBI. Do not submit CBI to EPA through https://www.regulations.gov or email. If you wish to include CBI in your comment, please follow the applicable instructions at https://www.epa.gov/​dockets/​commenting-epa-dockets#rules and clearly mark the information that you claim to be CBI. Information so marked will not be disclosed except in accordance with procedures set forth in 40 CFR parts 2 and 703, as applicable.

2. Tips for preparing your comments. When preparing and submitting your comments, see the commenting tips at https://www.epa.gov/​dockets/​commenting-epa-dockets.

II. Background

A. What is 1,2-Dichloroethane?

1,2-Dichloroethane, also known as ethylene dichloride or EDC (CASRN 107-06-2), is a volatile, colorless, oily liquid with a chloroform-like odor that is used primarily in the synthesis of vinyl chloride; over 90 percent of 1,2-dichloroethane is manufactured to be converted to vinyl chloride. It is soluble in water (8,600 mg/L) and is miscible in most organic solvents. Between 2016 and 2019, production volume of 1,2-dichloroethane was reported to be between 30 to 40 billion pounds, based on the 2020 TSCA Chemical Data Reporting data.

B. Summary of Activities for the Risk Evaluation of 1,2-Dichloroethane

In December 2019, EPA announced its designation of 1,2-dichloroethane as a high priority substance for risk evaluation under TSCA (Ref. 1). In April 2020, EPA sought public comment on the draft scope of the 1,2-dichloroethane risk evaluation (Ref. 2), and after considering public comments, issued the final scope in September 2020 (Ref. 3). In July 2024, EPA released the Draft Human Health Hazard Assessment for 1,2-Dichloroethane for public comment and external peer review by the Science Advisory Committee on Chemicals (SACC) (Ref. 4). As part of the SACC deliberations, the Agency held a virtual public meeting to discuss the Draft Risk Evaluation for 1,1-Dichloroethane as well as the Draft Human Health Hazard Assessment for 1,2-Dichloroethane in September 2024. For more information about this meeting, go to the SACC website at https://www.epa.gov/​tsca-peer-review/​science-advisory-committee-chemicals-meetings. In June 2025, EPA released a response to comments document titled, “Summary of and Response to External Peer Review and Public Comments on the Risk Evaluation for 1,1-Dichloroethane and Human Health Hazard Technical Support Document for 1,2-Dichloroethane” (Ref 5). These documents, other supporting documents, and public comments are in dockets EPA-HQ-OPPT-2018-0427 and EPA-HQ-OPPT-2024-0114. The draft risk evaluation for 1,2-dichloroethane is being released with this notice.

Due to prior review, EPA is not soliciting additional peer review of the human health hazard assessment. Additional external peer review is also not needed on the other components of the draft risk evaluation because (1) the Draft Human Health Hazard Assessment for 1,2-Dichloroethane was peer reviewed by the SACC (Ref. 4); and (2) the methodologies used in the development of the 1,2-dichloroethane draft risk evaluation have been previously peer reviewed by the SACC in published risk evaluations for 1,1-dichloroethane (Ref. 5), carbon tetrachloride (Ref. 6), methylene chloride (Ref. 7), perchloroethylene (Ref. 8), and trichloroethylene (Ref. 9), as well as the Draft TSCA Screening Level Approach for Assessing Ambient Air and Water Exposures to Fenceline Communities (Ref. 10). This draft risk evaluation reflects SACC and public comments received on the Draft Human Health Hazard Assessment for 1,2-Dichloroethane.

III. Request for Comment

EPA seeks feedback on the assessment of risk presented in the draft risk evaluation for 1,2-dichloroethane, a copy of which is available in the docket, and encourages all potentially interested parties, including individuals, governmental and non-governmental organizations, non-profit organizations, academic institutions, research institutions, and private sector entities to comment on the draft risk evaluation. To the extent possible, the Agency asks commenters to please cite any public data related to or that support comments provided, and to the extent permissible, describe any supporting data that is not publicly available.

EPA welcomes specific input on each section of the draft risk evaluation, particularly input on the following:

• The approach taken to evaluate the byproducts in theDraft Byproducts Assessment for 1,2-Dichloroethane;
• The COU names and descriptions for “Industrial use—other use—process solvent,” particularly whether there is overlap between this use as a process solvent in chemical reactions (including a proprietary use in pesticide, fertilizer, and other agricultural chemical manufacturing) and other processing or industrial and commercial COUs that may duplicate this newly added COU (e.g., Processing—incorporated into a formulation, mixture, or reaction product);
• Whether the delineation of occupational exposure scenarios (OESs) associated with the Disposal COU are clear and accurate;
• Whether and how exposure controls and personal protective equipment (PPE) are used during the manufacture, processing, and use of 1,2-dichloroethane for each of the COUs. Although EPA has test order data, additional information on when and where exposure controls and PPE are used would be informative;
• All aspects of the approach for assessing ambient air inhalation exposure for the general population, including exposure input assumptions, uncertainties, as well as the calculation and interpretation of additional cancer cases based on the population exposed;
• Information on environmental releases for OESs for which releases were modeled (Repackaging, Application of adhesives and sealants, Industrial and commercial non-aerosol cleaning/degreasing, Application of lubricants and greases, Industrial and commercial aerosol products, and Laboratory use); and
• Information on OESs for which EPA has slight confidence on exposures to workers and ONUs (Repackaging, Industrial and commercial aerosol products, and Waste handling, treatment, and disposal [landfills]), including on the degree to which 1,2-dichloroethane is used in Industrial and commercial aerosol products. Information to help clarify the approach EPA used to analyze OSHA CEHD, specifically the step of removing data in which all measurements taken at the site were recorded as “0” or below the limit of detection and there was no evidence such as a bulk sample that shows the presence of the chemical at the site as EPA assumed that the chemical of interest may not have been at the site at the time of sampling; and
• Information (e.g., SDS documents) to inform the level of 1,2-dichloroethane in adhesives. The concentration evaluated for the dermal exposure for the Industrial application of adhesives and sealants OES is 91.8 percent based ( printed page 52056) on an SDS for an adhesive containing 1,2-dichloroethane.

IV. Next Steps

EPA will consider comments received on the draft risk evaluation and announce the availability of the final risk evaluation for 1,2-dichloroethane.

Under TSCA section 6, EPA must determine in the final risk evaluation, based on the weight of scientific evidence, whether or not the chemical presents an unreasonable risk to health or the environment under the chemical's COUs. This includes consideration of risks to potentially exposed or susceptible subpopulations who may be at greater risks than the general population, such as children and workers. TSCA prohibits EPA from considering non-risk factors ( e.g., costs/benefits) during risk evaluation.

If EPA determines in its final risk evaluation that a chemical presents an unreasonable risk to health or the environment, the chemical will move to risk management action under TSCA section 6(a) for the relevant COUs. EPA would be required to implement, via regulation, regulatory restrictions on the manufacture (including import), processing, distribution, use or disposal of the chemical to eliminate the identified unreasonable risk. TSCA section 6(a) includes a range of risk management options, including labeling, recordkeeping or notice requirements, actions to reduce human exposure or environmental release, and a ban of the chemical or of certain uses. Like the prioritization and risk evaluation processes, there is an opportunity for public comment on any proposed risk management actions.

For more information about the TSCA risk evaluation process for existing chemicals, go to https://www.epa.gov/​assessing-and-managing-chemicals-under-tsca.

V. References

The following is a listing of the documents that are specifically referenced in this document. The docket includes these documents and other information considered by EPA, including documents that are referenced within the documents that are included in the docket, even if the referenced document is not physically located in the docket. For assistance in locating these other documents, please consult the person listed under FOR FURTHER INFORMATION CONTACT .

1. EPA. High-Priority Substance Designations Under the Toxic Substances Control Act (TSCA) and Initiation of Risk Evaluation on High-Priority Substances; Notice of Availability. Federal Register . 84 FR 71924, December 30, 2019 (FRL-10003-15).

2. EPA. Draft Scopes of the Risk Evaluations To Be Conducted for Thirteen Chemical Substances Under the Toxic Substances Control Act; Notice of Availability. Federal Register . 85 FR 19941, April 9, 2020 (FRL-10007-11).

3. EPA. Final Scopes of the Risk Evaluations To Be Conducted for Twenty Chemical Substances Under the Toxic Substances Control Act; Notice of Availability. Federal Register . 85 FR 55281, September 4, 2020 (FRL-10013-90).

4. EPA. 1,1-Dichloroethane and 1,2-Dichloroethane; Science Advisory Committee on Chemicals (SACC) Peer Review; Notice of SACC Meeting, Availability of Draft Documents and Request for Comment. Federal Register . 89 FR 54815, July 2, 2024 (FRL-11809-03).

5. EPA. 1,1-Dichloroethane; Risk Evaluation Under the Toxic Substances Control Act (TSCA); Notice of Availability. Federal Register . 90 FR 26581, June 23, 2025 (FRL-11809-04).

6. EPA. Carbon Tetrachloride (CCl4); Final Toxic Substances Control Act (TSCA) Risk Evaluation; Notice of Availability. Federal Register . 85 FR 70147, November 4, 2020 (FRL-10015-51).

7. EPA. Methylene Chloride (MC); Final Toxic Substances Control Act (TSCA) Risk Evaluation; Notice of Availability. Federal Register . 85 FR 37942, June 24, 2020 (FRL-10011-16).

8. EPA. Perchloroethylene (PCE); Final Toxic Substances Control Act (TSCA) Risk Evaluation; Notice of Availability. Federal Register . 85 FR 82474, December 18, 2020 (FRL-10017-44).

9. EPA. Trichloroethylene (TCE); Final Toxic Substances Control Act (TSCA) Risk Evaluation; Notice of Availability. Federal Register . 85 FR 75010, November 24, 2020 (FRL-10016-91).

10. EPA. Science Advisory Committee on Chemicals (SACC); Notice of Public Meeting and Request for Comments on Draft Toxic Substances Control Act (TSCA) Screening Level Approach for Assessing Ambient Air and Water Exposures to Fenceline Communities. Federal Register . 87 FR 3294. January 21, 2022 (FRL-9392-01).

Authority:15 U.S.C. 2601 et seq.

90 FR 52054