EPA list of extremely hazardous substances

Extremely Hazardous Substances (EHS) are a set of chemicals identified by the United States Environmental Protection Agency (EPA) as posing a significant risk to human health and the environment in the event of a release or spill. The management and regulation of these substances are critical components of the Emergency Planning and Community Right-to-Know Act (EPCRA), which was enacted as part of the Superfund Amendments and Reauthorization Act (SARA) in 1986. This legislation requires facilities that use, store, or manufacture these substances in quantities above certain thresholds to report their activities and to develop emergency response plans in coordination with local emergency planning committees.

Identification and Regulation

The EPA's list of Extremely Hazardous Substances is detailed in Appendix A of 40 CFR Part 355. The list includes chemicals based on their acute lethal toxicity, as well as their potential for causing serious or irreversible health effects. The criteria for listing include factors such as toxicity, reactivity, volatility, dispersibility, and the potential for exposure to the population. Chemicals like sulfur dioxide, ammonia, and chlorine are examples of substances that have been designated as EHS due to their high toxicity and potential for widespread harm in the event of an uncontrolled release.

Reporting Requirements

Facilities that have EHS in quantities exceeding the threshold planning quantity (TPQ) must comply with several reporting requirements under EPCRA. These include:

• Submitting an emergency and hazardous chemical inventory form (Tier II) annually to local fire departments, Local Emergency Planning Committees (LEPC), and State Emergency Response Commissions (SERC).
• Notifying the LEPC and SERC immediately following the release of an EHS in a quantity that equals or exceeds the reportable quantity (RQ) as specified by the EPA.

Emergency Planning

Facilities subject to EPCRA Section 302 must also participate in emergency planning activities with their LEPC. This involves:

• Identifying routes likely to be used for the transportation of EHS.
• Describing emergency response procedures and methods for notifying the public and local emergency response agencies about accidental releases.
• Designating a facility emergency coordinator to participate in the local emergency planning process.

Community Right-to-Know

The Community Right-to-Know provisions under EPCRA enable communities to be informed about potential chemical hazards in their area. Facilities must provide Material Safety Data Sheets (MSDS) or Safety Data Sheets (SDS) for EHS and other hazardous chemicals upon request to local emergency planning committees, fire departments, and the public.

List of Extremely Hazardous Substances

The EPA's list of Extremely Hazardous Substances includes hundreds of chemicals. Some notable examples include:

• Arsenic
• Cyanide
• Dioxin
• Hydrogen sulfide
• Mercury
• Phosgene

This list is incomplete; you can help WikiMD by expanding it.

See Also

• Chemical safety
• Hazardous waste
• Toxic Substances Control Act
• Risk management (environmental)