EPA to Conduct TSCA Risk Evaluation for 1,3-Butadiene
On September 18, 2024, the U.S. Environmental Protection Agency (EPA) announced its plan to conduct a draft risk evaluation for 1,3-butadiene under the Toxic Substances Control Act (TSCA). This evaluation will determine whether the chemical poses unreasonable risks to human health or the environment.
1,3-butadiene is a volatile, colorless gas widely utilized in petrochemical industries for producing polymers and elastomers. The chemical’s annual production volume ranges between 1 and 5 billion pounds, with over 98% of its emissions released into the atmosphere, according to EPA data. The EPA classifies 1,3-butadiene as a human carcinogen, with studies linking exposure to increased leukemia rates among workers. Additionally, reduced fetal weight and hematological effects have been associated with this chemical.
EPA’s Risk Evaluation Process
Under TSCA Section 6(b), 1,3-butadiene is listed as a high-priority chemical, undergoing a three-stage evaluation process:
- Prioritization: Identifying chemicals that may present risks.
- Risk Evaluation: Comprehensive analysis of chemical properties, exposure pathways, and health and environmental impacts.
- Risk Management: Developing regulatory measures to mitigate risks.
Scientific Integrity and Public Participation
To ensure scientific rigor, the EPA is seeking nominations for experts to join the Science Advisory Committee on Chemicals (SACC). Nominations are open until October 18, 2024.
The SACC comprises 20 independent experts in fields like toxicology, environmental risk assessment, and exposure analysis. The draft risk evaluation will be published in the Federal Register in fall 2024 for public comment, with peer review scheduled for early 2025.
Environmental Implications of 1,3-Butadiene
Primarily emitted into the atmosphere, 1,3-butadiene poses a risk not only to workers but also to the general population. The EPA’s comprehensive evaluation aims to provide actionable insights to mitigate these risks and protect both human health and the environment.