Ethylene Glycol n-mono Butyl Ether (EGBE) RELs – Draft for Scientific Review Panel on Toxic Air Contaminants (SRP)

The Office of Environmental Health Hazard Assessment (OEHHA) is releasing a revised draft document summarizing the toxicity and derivation of RELs for Ethylene Glycol n-mono Butyl Ether (EGBE).  These documents will be reviewed and discussed by the Scientific Review Panel on Toxic Air Contaminants (SRP) at its meeting on December 14, 2016 in Sacramento, CA.  RELs are airborne concentrations of a chemical that are not anticipated to result in adverse non–cancer health effects for specified exposure durations in the general population, including sensitive subpopulations.

OEHHA is required to develop guidelines for conducting health risk assessments under the Air Toxics Hot Spots Program (Health and Safety Code Section 44360(b)(2)). In response to this statutory requirement, OEHHA develops RELs for many air pollutants. The EGBE RELs were developed using the most recent “Air Toxics Hot Spots Program Technical Support Document for the Derivation of Noncancer Reference Exposure Levels,” finalized by OEHHA in 2008.

A draft of the EGBE REL document was released for a 60-day public review and comment period on August 14, 2015.  One set of comments was received.  The EGBE REL document was revised in response to those comments.  The post-public comment version of the EGBE REL document and the Responses to those comments were released on February 3, 2016, and reviewed by the SRP on March 4, 2016.  The EGBE REL document version being released today has been revised in response to the comments made by the SRP during the March 4, 2016 meeting.

The values proposed are as follows:

  • Acute REL (for a 1–hour exposure):  4700 micrograms per cubic meter (µg/m3)
  • 8–Hour REL (for repeated 8–hour exposures):  164 µg/m3
  • Chronic REL (for long–term exposures):  82 µg/m3

We are not seeking further comments from the public on the draft document.

Please direct any inquiries concerning technical matters or availability of the documents to:

Dr. John Budroe
Chief, Air Toxicology and Risk Assessment Section
Air, Community, and Environmental Research Branch
Office of Environmental Health Hazard Assessment
1515 Clay Street, 16th Floor
Oakland, CA, 94612

Telephone: (510) 622-3145

Information about dates and agenda for meetings of the Scientific Review Panel can be obtained from the California Air Resources Board web page at: