The Office of Environmental Health Hazard Assessment (OEHHA) of the California Environmental Protection Agency is announcing the availability of a draft document describing a proposed health-protective concentration (HPC) for noncancer effects of hexavalent chromium (Cr(VI)) in drinking water, as part of the update to the Cr(VI) Public Health Goal (PHG). A separate document describing the derivation of the HPC for cancer effects will be released at a later date.
A PHG is the level of a drinking water contaminant at which adverse health effects are not expected to occur from a lifetime of exposure. Cr(VI) is a known human carcinogen. For carcinogens, health-protective water concentrations are determined for both cancer and noncancer effects, and the lowest (most health-protective) value is selected as the PHG. The California Safe Drinking Water Act of 1996 requires OEHHA to develop PHGs based exclusively on public health considerations. PHGs published by OEHHA are considered by the State Water Resources Control Board in setting drinking water regulatory standards (Maximum Contaminant Levels, or MCLs) for California.
The draft technical support document, available for download, presents the scientific information available on the noncancer toxicity of Cr(VI), and the calculation of the proposed HPC for noncancer effects. The proposed HPC of 5 parts per billion (ppb) is based on chronic liver inflammation in female rats exposed to Cr(VI) in drinking water. As noted above, an HPC based on cancer will be released at a later date. Once cancer and noncancer HPCs have been determined, the lowest value will be selected as the PHG.
Any interested person or their authorized representative may submit public comments relevant to the proposed HPC. The public comment period for the draft document begins November 24, 2023 and ends January 8, 2024. The public is encouraged to submit written comments via OEHHA’s website, rather than in paper form. Comments may be submitted electronically through the following link: https://oehha.ca.gov/comments.
Hard-copy comments may be mailed or hand-delivered to the address below. Any written comments concerning this draft PHG document, regardless of the form or method of transmission, must be received by the PHG program by January 8, 2024, to be considered.
Following the workshop, public comment period and external scientific peer review, OEHHA will evaluate all the comments received, revise the document as appropriate, and make it available for an additional 30–day public comment period. After any subsequent revisions, the final document will be posted on the OEHHA website along with responses to the external peer review comments and to major comments received at the workshop and during the two public comment periods.
OEHHA is subject to the California Public Records Act and other laws that require the release of certain information upon request. If you provide comments, please be aware that your name, address, and e–mail may be available to third
parties.
If you would like to receive further information on this announcement or have questions, please contact Hermelinda Jimenez at PHG.Program@oehha.ca.gov or at (916) 324–7572.
Pesticide and Environmental Toxicology Branch
Office of Environmental Health Hazard Assessment
California Environmental Protection Agency
P.O. Box 4010, MS–12B
Sacramento, California 95812–4010
Attention: PHG Program
