News Details

The United States has submitted a notification to the World Trade Organization (WTO) under the Technical Barriers to Trade (TBT) Agreement, informing WTO members of a significant regulatory development concerning 1,3-Butadiene. Circulated on January 8, 2026, the notification relates to a finding issued by the Environmental Protection Agency (EPA) under the Toxic Substances Control Act (TSCA). 

Key Regulatory Development 

EPA has announced the availability of its final risk evaluation for 1,3-Butadiene (CAS RN 106-99-0). Following a comprehensive review using the best available scientific evidence, the agency concluded that the chemical poses an unreasonable risk to human health under certain conditions of use. This determination was made without consideration of costs or non-risk factors, in line with TSCA requirements. 

Scope of the Evaluation 

According to the notification, the evaluation covers activities related to the chemical industry and the environmental protection sectors. These include: 

• Production and use of 1,3-Butadiene 

• Products of the chemical industry 

• Relevant industrial and environmental applications 

The assessment also considered risks to potentially exposed or susceptible subpopulations, where relevant. 

Next Steps and Risk Management 

Following the unreasonable risk determination, EPA has indicated that it will now initiate risk management actions aimed at addressing the identified health concerns. Specific measures and timelines for adoption and entry into force have not yet been determined. 

Supporting Documentation 

The final risk evaluation was published in the Federal Register on 5 January 2026. and is supported by extensive docket materials available through Regulations.gov. Earlier draft evaluations and peer review processes were conducted with input from the Science Advisory Committee on Chemicals (SACC).