Draft Air Toxics Hot Spots Program Guidance Manual for the Preparation of Risk Assessments for the Scientific Review Panel Oct 2014

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The Office of Environmental Health Hazard Assessment (OEHHA) is releasing the State’s Science Review Panel on Toxic Air Contaminants (SRP) draft document, Air Toxics Hot Spots Program Guidance Manual for the Preparation of Risk Assessments for review and comment by the panel at the Science Review Panel Meeting on November 12, 2014. This draft Guidance Manual has been developed by OEHHA, in conjunction with the Air Resources Board, for use in implementing the Air Toxics Hot Spots Program (Health and Safety Code Section 44360 et. seq.). OEHHA is required to develop guidelines for conducting health risk assessments under Section 44360(b)(2).
OEHHA developed three Technical Support Documents (TSDs) that provide the scientific basis for numeric values used in assessing health risks from exposures to facility emissions. The three TSDs describe non-cancer risk assessment (Technical Support Document for the Derivation of Noncancer Reference Exposure Levels, 2008), derivation of cancer potency factors (Technical Support Document for Cancer Potency Factors: Methodologies for derivation, listing of available values, and adjustments to allow for early life stage exposures, 2009), and exposure assessment methodology including stochastic risk assessment (Technical Support Document for Exposure Assessment and Stochastic Analysis, 2012). These TSDs underwent public and peer review, were approved by the State’s Scientific Review Panel, and adopted by OEHHA for use in the Air Toxics Hot Spots program. The SRP draft Guidance Manual combines the critical information from the three TSDs into a guidance manual for the preparation of health risk assessments. The Guidance Manual will now undergo review by the Scientific Review Panel.

The draft Guidance Manual was released for a 60-day public review and comment period on June 20, 2014.  Four sets of comments were received during this period.  Responses to these comments are also being released at this time, and are available below.  Changes based on these comments have been made to the Scientific Review Panel draft Guidance Manual.  Green highlight in the document are areas we specifically asked for the public to consider in their comments.  The yellow highlighted areas are changes made based on the comments received.

We are not seeking further comments from the public on the draft Guidance Manual at this time.

Please direct any inquiries concerning technical matters or availability of the documents to:
Dr. John Budroe
Air Community and Environmental Research Branch
Office of Environmental Health Hazard Assessment
1001 I St
Sacramento, CA, 95814
E–mail: John.Budroe@oehha.ca.gov
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.

Public Comments