Initiation of Risk Assessments for Chemicals in Drinking Water (2014)

The Calderon-Sher California Safe Drinking Water Act of 1996 requires the Office of Environmental Health Hazard Assessment (OEHHA) to post notices on its web site of water contaminants for which it is initiating development of public health goals (PHGs).  PHGs are concentrations of chemicals in drinking water that are not anticipated to produce adverse health effects. PHGs are non-regulatory in nature but are to be used as the health basis to update the state's primary drinking water standards (maximum contaminant levels, or MCLs) established by the State Water Resources Control Board (SWRCB) for chemicals subject to regulation.

This public notice announces the initiation of reviews for nine chemicals:

  • Carbofuran
  • Diquat
  • Endrin
  • Radium-226
  • Radium-228
  • Strontium-90
  • Thiobencarb
  • Toxaphene
  • Tritium

Updates of existing PHGs for these chemicals are being initiated based on the availability of new data, methodology updates, environmental exposures, and/or potential significance.  OEHHA is requesting information on these contaminants that could assist in updating the risk assessment and potentially calculating a revised PHG.

OEHHA’s 2014 Initiation Report, which provides information the office has identified to date as relevant to the preparation of the PHG on the chemicals covered in this notice is available for download below.

All information submitted to OEHHA in response to this request is considered public.  Please do not submit proprietary information.  In order to be considered during the update process, OEHHA must receive information by 5:00 p.m. on Monday, November 17, 2014.  We encourage you to submit information in electronic form, rather than in paper form. Information transmitted by e-mail should be addressed to with the chemical name in the subject line.  Information submitted in paper form may be mailed or delivered in person to the address below:

Hermelinda Jimenez
PHG Program
Pesticide and Environmental Toxicology Branch
Office of Environmental Health Hazard Assessment
1515 Clay St., 16th floor
Oakland, California 94612
If you have any questions, please contact Ms. Hermelinda Jimenez at (510) 622-3173 or email