Home Air Non-cancer Health Effects (RELs)

Air Toxicology and Epidemiology

View the Table of OEHHA Acute, 8-hour and Chronic Reference Exposure Level (REL)s

• Notice of Adoption of Revised Reference Exposure Levels For Nickel And Nickel Compounds
  [03/23/12]
• Materials for Consideration by the Scientific Review Panel at Their Next Meeting (August 30, 2011)
  Air Toxics Hot Spots Program – Proposed Reference Exposure Levels For Caprolactam And Nickel
  [07/29/11]
• Proposed Reference Exposure Levels for Caprolactam and Nickel
  [04/01/11]
• Materials for Consideration by the Scientific Review Panel at Their Next Meeting (January 21, 2011) [12/27/10]
  • Proposed Revisions to the Technical Support Document for Cancer Potency Factors, Appendix C - Use of the Toxicity Equivalency Factor (TEFWHO 97 and TEFWHO 05) Scheme for Estimating Toxicity of Mixtures of Dioxin-Like Chemicals
  • Proposed Reference Exposure Levels for Caprolactam
• Proposed Revised Reference Exposure Levels For Nickel And Nickel Compounds
  [06/04/10]
• Proposed Reference Exposure Levels For Methylene Diphenyl Diisocyanate, Toluene Diisocyanate And Caprolactam: Announcement Of Public Workshops
  [06/02/10]
• Proposed Reference Exposure Levels for Caprolactam
  [05/20/10]
• Proposed Revised Reference Exposure Levels For Toluene Diisocyanate And Methylene Diphenyl Diisocyanate
  [04/23/10]
• Adoption of the Revised Air Toxics Hot Spots Program Technical Support Document for the Derivation of Noncancer Reference Exposure Levels and RELs for Six Chemicals
  [12/19/08]
• Adoption of Chronic Reference Exposure Levels for Silica (crystalline, respirable)
  [02/10/05]
• Document Available: Draft Chronic Reference exposure for Silica (Crystalline, respirable), and OEHHA's responses to public comments
  [11/03/04]
• Air Toxic Hot Spots Program - Chronic Toxicity Summary: Silica (Crystalline, Respirable).  Materials for Review by the Scientific Review Panel for Air Toxics
  [03/18/04]
• Adoption of Chronic Reference Exposure Level for Fluorides Including Hydrogen Fluoride
  [08/14/03]
• Notice of Extension of Public Comment Period Air Toxic Hot Spots Program - Chronic Toxicity Summary: Silica (Crystalline, Respirable)
  [05/16/03]
• Notice of Public Comment Period on Air Toxics Hot Spots Program - Chronic Toxicity Summary Silica (Crystalline, Respirable)
  [04/25/03]
• Notice to Interested Parties Substances to be included in the Air Toxics Hot Spots Program Risk Assessment Guidelines, Part III: Technical Support Document "Determination of Noncancer Chronic Reference Exposure Levels": Phosphine and Triethylamine
  [09/03/02]
• Notice to Interested Parties Discussion of substances to be included in the Air Toxics Hot Spots Program Risk Assessment Guidelines, Part III: Technical Support Document "Determination of Noncancer Chronic Reference Exposure Levels": Fluorides including Hydrogen Fluoride, Phosphine and Triethylamine
  [07/10/02]
• Notice to Interested Parties Adoption of Chronic Reference Exposure Level for Carbon Disulfide
  [05/17/02]
• Notice to Interested Parties Discussion of substances to be included in the Air Toxics Hot Spots Program Risk Assessment Guidelines, Part III: Technical Support Document "Determination of Noncancer Chronic Reference Exposure Levels"
  [04/19/02]
• Adoption of Chronic Reference Exposure Levels (RELs) for Airborne Toxicants
  [12/28/01]
• Air Toxics Hot Spots Program Risk Assessment Guidelines Part III. The Determination of Chronic Reference Exposure Levels - 22 Chemicals
  [01/22/01]
  • Download the 22 chemical summaries
• Notice of Public Comment Period on Air Toxics "Hot Spots" Program Risk Assessment Guidelines
  [07/21/00]
• Air Toxics Hot Spots Program Risk Assessment Guidelines Part III. The Determination of Chronic Reference Exposure Levels for Airborne Toxicants - 16 Chemicals
  [05/02/00]
  • Download the 16 Chemical Summaries
• Air Toxics Hot Spots Program Risk Assessment Guidelines Part III. The Determination of Chronic Reference Exposure Levels for Airborne Toxicants. 22 Chemicals
  [02/23/00]
  • Download Risk Assessment Guidelines, Part III
    (includes methodology for developing chronic RELs and the first 22 chemical summaries)
• Notice to Interested Parties Notice of Public Comment Period on Air Toxics "Hot Spots" Program Risk Assessment Guidelines - 2nd Set of 40 Chronic RELs - Comment Period Closed (10/27/99)
  [09/27/99]
• Air Toxics Hot Spots Program Risk Assessment Guidelines Part III. The Determination of Noncancer Chronic Reference Exposure Levels for Airborne Toxicants (22 chemicals) and OEHHA's Responses to Public Comments - Revised DRAFT
  [06/11/99]
• Air Toxics Hot Spots Program Risk Assessment Guidelines
  Part I. Technical Support Document for The Determination of Acute Reference Exposure Levels for Airborne Toxicants.
  [04/05/99]
• Response to Comments on the Scientific Review Panel Draft of the Air Toxic Hot Spots Risk Assessment Guidelines Part 1: Determination of Acute Reference Exposure Levels for Airborne Toxicants (received by OEHHA Jan. 18, 1999)
  [03/01/99]
• Download Risk Assessment Guidelines Part I and Response to Comments on the Scientific Review Panel Draft of the Air Toxic Hot Spots Risk Assessment Guidelines Part 1: Determination of Acute Reference Exposure Levels for Airborne Toxicants (November 1998
  [02/04/99]
• OEHHA (1995) Responses to Public Comments on Determination of Acute Toxicity Levels for Airborne Toxicants and Evaluation of Acute Non-Cancer Health Effects
  [01/29/99]
• Notice to Interested Parties
  Notice of Public Comment Period on Air Toxic "Hot Spots" Program Risk Assessment Guidelines, Part II: Technical Support Document for the Determination of Acute Reference Exposure Levels for Airborne Toxicants. - Comment Period Closed (11/30/1998)
  [10/30/98]
• Notice to Interested Parties Notice of Extension of Public Comment Period for Air Toxics "Hot Spots" Guidelines Part III: Technical Support Document for Determining Chronic Reference Exposure Levels - Comment Period Closed (01/29/98)
  [12/26/97]
• Notice to Interested Parties October 31, 1997 Notice of Public Comment Period and Notice of Public Workshops on Air Toxic "Hot Spots" Program Risk Assessment Guidelines, Part III: Technical Support Document for the Determination of Noncancer Chronic Reference Exposure Levels - Comment Period Closed (12/30/97)
  [10/01/97]

Flex Your Power Web site

Energy efficiency and conservation information. Find incentives/rebates, technical assistance, retailers, product guides, case studies and more.

AMBER ALERT: Save a Child

AMBER ALERT empowers law enforcement, the media and the public to combat abduction by sending out immediate information.