Air Toxics Hot Spots
The Air Toxics "Hot Spots" Information and Assessment Act (AB 2588, Connelly) was enacted in 1987, and requires stationary sources of pollutants to report the types and quantities of certain substances routinely released into the air. The goals of the Air Toxics "Hot Spots" Act are to collect emission data, to identify facilities having localized impacts, to ascertain health risks, to notify nearby residents of significant risks, and to reduce those significant risks to acceptable levels.
Guideline Values for Health Risk Assessment
- Hot Spots Unit Risk and Cancer Potency Values
- Acute, 8-hour, and Chronic Reference Exposure Level (RELs)
Current Hot Spots Guidelines Technical Support Documents
Hot Spots Reports, Notices and Documents
Mar 26, 2024: Inhalation Unit Risk Factor (IUR) for Isoprene
The Office of Environmental Health Hazard Assessment is announcing the availability of a draft document for public review summarizing the carcinogenicity data and deriving a cancer inhalation unit...
Oct 11, 2023: OEHHA Acute, 8-hour and Chronic Reference Exposure Level (REL) Summary
Summary table of all OEHHA acute, 8-hr and chronic Reference Exposure Levels (chRELs) as of August 2020. Documentation for these values is available in the Air Toxics Hot Spots Program Guidance...
Oct 6, 2023: Notice of Adoption of Reference Exposure Levels for Trimethylbenzenes
The Office of Environmental Health Hazard Assessment is adopting new Reference Exposure Levels for Trimethylbenzenes for use in the Air Toxics Hot Spots Program. Reference Exposure Levels are...
Aug 4, 2023: Notice of Adoption of Revised Cancer Inhalation Unit Risk Factors for Cobalt Sulfate Heptahydrate and Water-Soluble Cobalt Compounds
The Office of Environmental Health Hazard Assessment is adopting revised cancer inhalation unit risk (IUR) and slope factors for cobalt and water-soluble cobalt compounds for use in the Air Toxics...
May 11, 2023: Notice Of Extension Of The Public Comment Period On A Draft Cancer Inhalation Unit Risk Factor For Ethylene Oxide
The Office of Environmental Health Hazard Assessment is announcing the webcast option for the Northern California Public Workshop on releasing a draft document for public review that summarizes the...
Apr 28, 2023: Notice of Adoption of Reference Exposure Levels for 1-Bromopropane
The Office of Environmental Health Hazard Assessment is adopting new Reference Exposure Levels for 1-Bromopropane for use in the Air Toxics Hot Spots Program. Reference Exposure Levels are airborne...
Dec 9, 2022: Notice of Adoption of Cancer Inhalation Unit Risk and Slope Factors for 1-Bromopropane
The Office of Environmental Health Hazard Assessment (OEHHA) is adopting new cancer inhalation unit risk (IUR) and slope factors for 1-Bromopropane (1-BP) for use in the Air Toxics Hot Spots Program.
Aug 31, 2022: Chromium, Trivalent (Inorganic Water-Soluble Compounds)
The Office of Environmental Health Hazard Assessment (OEHHA) is adopting new Reference Exposure Levels (RELs) for Chromium, Trivalent (Inorganic Water-Soluble Compounds) (Cr(III)) for use in the Air...
Apr 12, 2022: 1-Bromopropane Reference Exposure Levels (RELs) Document - Scientific Review Panel on Toxic Air Contaminants (SRP) Review Draft
The Office of Environmental Health Hazard Assessment is releasing a draft document summarizing the toxicity and derivation of Reference Exposure Levels for 1-Bromopropane . This document will be...
Jan 7, 2022: Public Comment Period and Workshop on the Draft Reference Exposure Levels for 1-Bromopropane
The Office of Environmental Health Hazard Assessment (OEHHA) is releasing a draft document for public review, summarizing the toxicity and derivation of proposed Reference Exposure Levels (RELs) for...