The U.S. Environmental Protection Agency (EPA) recently announced plans to regulate 15 industrial and commercial uses of 1,2-dichloroethane (1,2-DCA) under the Toxic Substances Control Act (TSCA). The decision follows EPA’s final risk evaluation, which determined that certain workplace activities involving the chemical present unreasonable risks to workers through inhalation and dermal exposure. Although the announcement does not yet impose new requirements, it marks the start of EPA’s risk management process and shows how the agency plans to reduce worker exposure while supporting industries that use the chemical.
What is 1,2-Dichloroethane?
1,2-Dichloroethane (1,2-DCA), also known as ethylene dichloride (EDC), is a high-volume industrial chemical used primarily to produce vinyl chloride monomer, the building block for polyvinyl chloride (PVC). According to EPA, more than 90 percent of thousands of tons of 1,2-DCA produced or imported in the United States is used for PVC production.
PVC is widely used in water, irrigation, and wastewater pipes; electrical and telecommunications insulation and conduit; healthcare products; building materials; transportation components; and many consumer goods. Given its widespread use across multiple industries, any future regulatory requirements affecting 1,2-DCA could have implications for a broad range of manufacturers and industrial facilities.
Under TSCA, EPA must determine whether a chemical presents an unreasonable risk to human health or the environment under its conditions of use. For 1,2-DCA, that evaluation is now complete, and EPA has moved into the next phase of the process: risk management.
Risk Evaluation Findings for 1,2-DCA
EPA’s final risk evaluation found that 15 of the 20 conditions of use evaluated for 1,2-DCA present unreasonable risks to workers who are exposed to the chemical directly or indirectly. According to the agency, those risks are driven primarily by inhalation and dermal exposure in occupational settings. The evaluation identified several potential health effects associated with repeated workplace exposure, including kidney toxicity, respiratory (nasal) effects, male reproductive toxicity, and increased cancer risk.
Five uses did not significantly contribute to unreasonable risks:
- Distribution in commerce
- Closed system heat transferring agent
- In fuels/related products
- Commercial use in plastic/rubber products
- Consumer use in plastic/rubber products.
Notably, the agency used workplace exposure data, where available, to replace default assumptions. However, the baseline risk evaluation did not take into account the use of personal protective equipment, such as respirators, or engineering controls that prevent excessive exposure.
Importantly, EPA did not identify unreasonable risks to consumers, the general population, including communities with high fish consumption, or the environment. On the latter, the agency considered aquatic vertebrates and invertebrates, algae, and wildlife at environmentally relevant concentrations. As a result, the agency’s forthcoming regulatory efforts are expected to focus on reducing occupational exposures rather than imposing broader restrictions on the chemical’s manufacture or use.
Risk Management Plans for 1,2-DCA
With the risk evaluation complete, EPA will now move into the risk management phase of the TSCA process. The agency intends to develop a TSCA Section 6(a) rule focused on the 15 conditions of use that contributed to its unreasonable risk determination. EPA has indicated that the rule may include measures such as engineering controls, workplace exposure limits, and personal protective equipment requirements designed to reduce occupational exposure.
As to the two byproducts formed during 1,2-DCA manufacture, trans-1,2-dichloroethylene and 1,1,2-trichloroethane, they will be assessed via separate risk evaluations. The agency also emphasized that future requirements will be informed by consultation with workers, businesses, labor organizations, state partners, and other stakeholders.
Potential Impacts for Industry
Although EPA has not yet proposed specific regulatory requirements, organizations that manufacture, process, or use 1,2-DCA may wish to begin evaluating how future risk management measures could affect their operations. Facilities that handle 1,2-DCA may face additional requirements related to exposure monitoring, engineering controls, workplace practices, or personal protective equipment. Depending on the final rule, companies could also be required to document compliance measures or demonstrate that worker exposures remain below established thresholds.
For many organizations, existing industrial hygiene programs and occupational safety procedures may already address some of these concerns. However, facilities may benefit from reviewing current exposure control strategies, workplace monitoring practices, and employee training programs to identify potential gaps before new requirements are finalized.
1,2-DCA plays a significant role in PVC production and broader manufacturing supply chains, so stakeholders across multiple industries may be interested in participating in the rulemaking process to better understand potential operational and compliance implications.
While risk evaluations for the main byproducts (trans-1,2-dichloroethylene and 1,1,2-trichloroethane) are pending, it would be appropriate to assess and implement worker protection measures for those two compounds as well.
Conclusion
EPA’s decision to regulate 15 uses of 1,2-DCA marks a significant step in the agency’s implementation of TSCA risk management requirements. As EPA develops a Section 6(a) rule, stakeholders will have opportunities to provide input on potential control measures, implementation challenges, and compliance considerations. For organizations that manufacture, process, or use 1,2-DCA, monitoring the rulemaking process and evaluating existing exposure control practices may help position facilities for future compliance. Trihydro will provide an update as the new risk management rule gets drafted.
We Can Help
Trihydro’s regulatory and health & safety experts are familiar with TSCA regulations. We can assist with rule interpretation, compliance, and recordkeeping, as well as developing worker exposure protection programs for 1,2-DCA and its byproducts.
