Cancer Inhalation Unit Risk Factor (IUR) for Isoprene

Jul 17, 2024

The Office of Environmental Health Hazard Assessment (OEHHA) is announcing the availability of a draft document for review by the Scientific Review Panel on Toxic Air Contaminants (SRP). This draft summarizes the carcinogenicity data and presents the derivation of a cancer inhalation unit risk factor (IUR) for isoprene, as part of the Air Toxics Hot Spots program. Cancer IURs are used to estimate lifetime cancer risks associated with inhalation exposure to a carcinogen.

Public Comment Draft

The public comment period for the draft isoprene IUR began on February 16, 2024 and ended on April 2, 2024. During the comment period, OEHHA held two public workshops. No public comments were received.

Public Workshops

Public workshops were held in Southern and Northern California to provide the public with an opportunity to ask questions and provide public comment about the cancer IUR for isoprene.

Southern California – in person
March 8, 2024, 9:00 AM – 12:00 PM
Room CC-2, South Coast Air Quality Management District
21865 E. Copley Drive, Diamond Bar, CA 91765

Northern California – in person and virtual
March 15, 2024, 9:00 AM – 12:00 PM
Sierra Hearing Room, Cal EPA Building
1001 I Street, Sacramento, CA 95814

Public Workshop Recording

Public Workshop Presentation