1-Bromopropane Cancer Inhalation Unit Risk Factor (IUR) Document - Scientific Review Panel on Toxic Air Contaminants (SRP) Review Draft

The Office of Environmental Health Hazard Assessment (OEHHA) is releasing a draft document summarizing the carcinogenicity and derivation of a cancer inhalation unit risk factor (IUR) for 1-Bromopropane (1-BP).  IURs are used to estimate lifetime cancer risks associated with inhalation exposure to a carcinogen. This document will be reviewed and discussed by the Scientific Review Panel on Toxic Air Contaminants (SRP) at its meeting on October 15, 2021. 

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 IURs for many air pollutants. This IUR was developed using the guidance in the most recent “Air Toxics Hot Spots Program Technical Support Document for Cancer Potency Factors,” finalized by OEHHA in 2009.

A draft of the 1-BP IUR document was released for a 45-day public review and comment period on May 12, 2021.  No public comments were received on the document.

The value proposed is as follows:

Inhalation Unit Risk Factor                        3.7 × 10-6 (µg/m3)-1

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 and Site Assessment and Climate Indicators Branch
Office of Environmental Health Hazard Assessment
1515 Clay Street, 16th Floor
Oakland, CA, 94612

E–mail: John.Budroe@oehha.ca.gov (link sends e-mail)
Telephone: (510) 906-2131

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