Proposal for the Adoption of a Unit Risk Value for Naphthalene - Materials for Review by the Scientific Review Panel for Air Toxics

Mar 18, 2004

The Office of Environmental Health Hazard Assessment (OEHHA) has developed a draft document describing a unit risk factor for estimating cancer risk associated with inhalation of naphthalene, for use in implementing the programs for Toxic Air Contaminants (Health and Safety Code Section 39650 et seq.) and Air Toxics Hot Spots (Health and Safety Code Section 44300 et seq.). In order to solicit public comment this draft document was made available on the OEHHA Web Site on January 23, 2004, commencing a public review period, including a public workshop, which ended on March 8, 2004.

OEHHA proposes a unit risk for use in estimating the lifetime cancer risk associated with inhalation exposures to naphthalene, based on the results of recent studies by the National Toxicology Program. The document, which describes toxicity data on naphthalene, and the derivation of the unit risk factor, is in the form of a toxicity summary to be included as an addendum to the Air Toxics Hot Spots Program Risk Assessment Guideline, Part II: Technical Support Document for Describing Available Cancer Potency Factors , along with additional background and supporting material.

OEHHA has received public comments on this document, which was amended in response. The modified document, along with the comments received and OEHHA's responses to them, will be presented to the Scientific Review Panel on Toxic Air Contaminants at their next meeting scheduled for ~~April 9, 2004~~ May 19th . The materials to be presented to the Panel are available as pdf files.

Further information about dates, locations and agenda for meetings of the Scientific Review Panel can be obtained from the ARB web page at http://www.arb.ca.gov/srp/srp.htm .