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 ethylene dibromide, 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 relevant 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 the scientific evidence, and 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 the draft risk evaluation under TSCA for ethylene dibromide. EPA used the best available science to prepare this draft risk evaluation and preliminarily determined, based on the weight of scientific evidence, that ethylene dibromide does pose unreasonable risk to human health driven primarily by certain COUs analyzed in the draft risk evaluation.

D. What should I consider as I submit my comments to EPA?

1. Submitting CBI

Do not submit CBI 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 Comments

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

II. Background for Ethylene Dibromide

A. What is ethylene dibromide?

Ethylene dibromide is a colorless and sweet-smelling volatile organic chemical and is primarily used in fuels and related products ( i.e., lead scavenger) in commercial and consumer leaded aviation fuel (“avgas”) to prevent engine fouling. Workers may be exposed to ethylene dibromide through liquid formulations or vapor when making or using these products. Occupational Non-User (ONU) exposure to ethylene dibromide is only anticipated through vapor exposure as direct handling of liquid formulations containing ethylene dibromide is not anticipated. Consumers may also be exposed to ethylene dibromide through liquid formulations or vapor during intended product use ( i.e., refueling small aircrafts with avgas). Environmental releases occur primarily through stack and fugitive emissions, where ethylene dibromide can subsequently undergo indirect photodegradation or wet deposition. Ethylene dibromide may also enter wastewater and, after treatment, be discharged in effluent from publicly owned treatment works.

B. The Risk Evaluation of Ethylene Dibromide

In December 2019, EPA announced its designation of ethylene dibromide (Docket ID: EPA-HQ-OPPT-2018-0488) as a High-Priority Substance for risk evaluation under TSCA (84 FR 71924 (FRL-10003-15-OCSPP)). In April 2020, EPA published and sought public comment on the draft scope of the ethylene dibromide risk evaluation (85 FR 19941 (FRL-10007-11-OCSPP)), and, after considering public comments, issued the final scope on September 4, 2020 (85 FR 55281 (FRL-10013-90-OCSPP)).

In this draft risk evaluation, EPA assessed human health acute, intermediate, and chronic non-cancer and cancer risks to workers and ONUs; acute, and intermediate non-cancer and cancer risks to consumers; and acute and chronic non-cancer and cancer risks to the general population (including fenceline communities and potentially exposed susceptible subpopulations or PESS). This draft risk evaluation also assessed acute and chronic risks to the environment, specifically to aquatic and terrestrial species.

C. Request for Comment

EPA seeks feedback on the assessment of risk presented in the draft risk evaluation for ethylene dibromide, 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, and is particularly interested in:

• Information to inform whether the data used (e.g., worker activities, process descriptions, exposure monitoring data) for the Incorporation into Formulation, Mixture or Reaction Product occupational exposure scenario (OES) is representative and reliable for today's exposures scenarios;
• Facility-specific information on days of operation and/or release to more accurately characterize environmental releases;
• Facility-specific information on days of operation and hours of operation per day for batch processes to accurately characterize occupational exposure;
• Any exposure monitoring data gathered from facilities relevant to current COUs for ethylene dibromide;
• Information to inform whether the data used for the Laboratory Use OES is representative and reliable for ongoing practices, including use-related information (e.g., volume of ethylene dibromide), workers activity-specific details ( e.g., typical working hours/day and days/year, frequency and duration of ethylene dibromide use on a typical workday, personal protective equipment (PPE) used), and site-specific information ( e.g., location of the site, engineering controls, size of laboratory site). EPA seeks further information on ( printed page 53620) exposures in federal and non-federal laboratories;
• Information from ethylene dibromide processing facilities on the current presence of laboratory sites within the same facilities;
• Information on the introduction of any exposure reduction related technologies or engineering controls since the 1980s;
• Information on PPE enforced by employers (e.g., assigned protection factor (APF) of respirators, materials of gloves, duration of respirator or gloves used) and used by workers in various activities under each OES;
• Average working hours per day and number of working days for a worker that refuels single engine small aircraft that utilize 100LL avgas containing ethylene dibromide as a fuel agent or additive;
• Number of aircrafts a worker (avgas refueler) refuels on a typical 8 hour workday;
• Avgas use patterns (e.g., frequency of refueling an aircraft per day, number of days flying an aircraft per year, average number of years that a consumer may fly and refuel their aircraft) for consumers ( i.e., pilots of small non-commercial airplanes);
• Racing fuel availability and use patterns (e.g., number or types of vehicles using racing fuel containing ethylene dibromide, volume of use, frequency of refueling);
• Average duration of refueling an aircraft (i.e., the duration of actively transferring avgas from nozzle into an aircraft fuel tank) and average volume of avgas refueled into an aircraft;
• Worker activities, industrial and commercial practices for the disposal of ethylene dibromide, and any exposure monitoring data gathered at landfills or wastewater treatment plants;
• EPA's draft Occupational Exposure Value (OEV) and Short-Term Exposure Value (STEV);
• Number of operating days per year and shift lengths at bulk terminals under the “Fuels and Related Products” OES;
• Information regarding engineering controls, administrative controls, and/or PPE use by workers engaged in refueling activities that reduce inhalation and dermal exposure to ethylene dibromide; and
• The representativeness of high-end exposure estimates for intermediate inhalation and dermal occupational exposures (e.g., current practices involving the processing of ethylene dibromide at neat concentrations).

III. Next Steps

After consideration of comments received from the public on the draft risk evaluation and input from the Scientific Advisory Committee on Chemicals (SACC) peer review, EPA will issue a final risk evaluation for ethylene dibromide. Under TSCA section 6, EPA must use the final risk evaluation as a basis to determine, based on the weight of scientific evidence, whether or not the chemical presents an unreasonable risk to human health or the environment under the chemical's COUs. This includes risks to 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.

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

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