Risk Management for 1,4-Dioxane
Below is information on EPA actions to manage risks from 1,4-dioxane. 1,4-Dioxane is used primarily as a solvent in a variety of commercial and industrial applications such as in the manufacture of other chemicals, as a processing aid, a laboratory chemical, and in adhesives and sealants. 1,4-Dioxane may also be found as a contaminant in consumer products such as soaps and detergents.
On this page:
- Final risk determination
- Managing risks of 1,4-dioxane
- Opportunities for public and stakeholder engagement
On other pages:
- Learn how EPA manages unreasonable risks from chemicals currently on the market.
- View a list of all chemicals undergoing risk evaluation, including docket numbers and agency points of contact.
Final Risk Determination
In November 2024, EPA released the final revised risk determination for 1,4-dioxane and the final supplement to the risk evaluation for 1,4-dioxane. The revised risk determination incorporates additional exposure pathways to the general public, including fenceline communities, and from 1,4-dioxane generated as a byproduct.
Overall, based on the revised risk determination, EPA’s findings include that worker exposure to 1,4-dioxane from all but four occupational conditions of use significantly contribute to the unreasonable risk from 1,4-dioxane. EPA's findings also include the risks to the general population and fenceline communities from drinking water sourced from surface water contaminated with 1,4-dioxane that is discharged from industrial facilities (including where it is produced as a byproduct) or commercial or consumer products such as detergents and cleaning products that are washed down the drain as contributing to the unreasonable risk. As required under TSCA, EPA must apply requirements of TSCA section 6(a) in a rule to address the unreasonable risk posed by 1,4-dioxane.
Regarding drinking water contaminated with 1,4-dioxane, EPA will coordinate steps to prevent or reduce risks to the general population under both TSCA section 6(a) and the Safe Drinking Water Act (SDWA). EPA’s Office of Chemical Safety and Pollution Prevention (OCSPP), which oversees TSCA, and EPA’s Office of Water (OW), which oversees SDWA, have signed a memo to document coordination on this matter.
Managing Risks of 1,4-Dioxane
The next step in the process required by TSCA is addressing the unreasonable risk identified in the 2024 revised risk determination and risk evaluation supplement. There are several actions EPA could take to address the identified risk, including regulations to prohibit or limit the manufacture, processing, distribution in the marketplace, use, or disposal of this chemical substance, or other options provided under TSCA as applicable. EPA is now in the process of developing ways to address the unreasonable risks identified and has up to one year to propose and take public comments on any risk management actions.
- Learn more about the unreasonable risks found in the final risk evaluation.
- Find information on ways to reduce exposure to this chemical as EPA works through the process required by TSCA to eliminate unreasonable risks from this chemical.
Opportunities for Public and Stakeholder Engagement
On February 2, 2021, EPA held a webinar on the TSCA risk management process and the findings in the final risk evaluation for 1,4-dioxane.
There will be additional opportunities for public and stakeholder engagement as EPA pursues the risk management process for this chemical. Similar to the risk evaluation process, there will also be opportunities for public comment as EPA works to propose and finalize risk management actions for the conditions of use where 1,4-dioxane presents an unreasonable risk.
- View a list of various public and stakeholder engagement opportunities related to risk management.
- You can reach out to the EPA point of contact for this chemical, listed at the top, right of this page, for more information or to schedule a one-on-one meeting.
- You can also stay informed by signing for our email alerts or checking the public docket at www.regulations.gov.