Notice of New Practice Regarding the Development of Proposition 65 Safe Harbor Levels for Newly Listed Chemicals
The Office of Environmental Health Hazard Assessment (OEHHA) of the California Environmental Protection Agency is the lead agency for the implementation of the Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65 or the Act). In order to provide compliance assistance for persons subject to the requirements of the Act, OEHHA develops Proposition 65 safe harbor levels - no significant risk levels (NSRLs) for carcinogens and maximum allowable dose levels (MADLs) for chemicals that cause reproductive toxicity. The NSRL is the daily intake level calculated to result in one excess case of cancer in an exposed population of 100,000, assuming lifetime (70-year) exposure at the level in question. The MADL is the level at which chemicals listed for reproductive toxicity would have no observable effect assuming exposure at 1,000 times that level. The NSRLs and MADLs are promulgated in Title 22, California Code of Regulations, sections 12705 and 12805 respectively. These levels assist interested parties in determining whether warnings are required for exposures to chemicals listed under Proposition 65, and whether certain discharges of listed chemicals to sources of drinking water are prohibited.
On November 2, 2007, OEHHA held a public workshop for the purpose of gathering input from interested parties concerning the relative importance of several proposed Proposition 65 regulatory actions and to gather input on potential regulatory items that should be considered. Several speakers suggested that OEHHA develop safe harbor levels for chemicals when they are added to the Proposition 65 list. OEHHA considered this suggestion and has determined that new internal practices regarding the development of safe harbor numbers can be implemented on a procedural basis, without the need for regulatory action.
OEHHA is therefore announcing a new practice regarding the development of safe harbor levels for newly listed chemicals. After a chemical is added to the Proposition 65 list, OEHHA as a general practice will strive to develop and release for public comment a draft safe harbor level within one year of the chemical’s listing. This one-year timeline is not mandatory or legally binding, but instead reflects OEHHA’s intent to provide draft safe harbor numbers in a timely manner that the public can use as guidance in determining when the warning requirement and discharge prohibition apply to newly listed chemicals. OEHHA may not be able to produce a draft safe harbor level within one year of a specific chemical’s listing or may decline to develop a safe harbor level for various reasons, such as resource limitations, competing workload priorities, or where development of a safe harbor level would be infeasible or unwarranted. Examples of such circumstances include but are not limited to: inadequate information on a chemical for quantitative risk assessment; or the likelihood of little or no human exposure to the chemical in California. The scientific complexity of developing a safe harbor level for a listing that is a complex mixture (e.g., environmental tobacco smoke) or a group or class of chemicals (e.g., polychlorinated biphenyls) may also delay or preclude developing such a level. Once a draft safe harbor level is released for public comment, OEHHA must adopt a final safe harbor level into regulation within one year, pursuant to the Administrative Procedure Act, or restart the regulatory process.
When issuing an official notice announcing the listing of a chemical, OEHHA will indicate in the notice whether it will initiate development of a draft safe harbor number at that time. If OEHHA decides against developing a safe harbor number for a newly listed chemical, the notice will state that members of the public who would like OEHHA to develop a safe harbor level for the chemical can submit a written request to OEHHA, along with their reason for wanting the safe harbor number. OEHHA will review any requests and then issue a written notice as to whether it will initiate development of a safe harbor number at that time.
In addition, OEHHA will continue to develop safe harbor numbers for currently listed chemicals.
- Public Workshop: Request for Public Participation in a Proposition 65 Regulatory Update Project