The California Office of Environmental Health Hazard Assessment’s (OEHHA) has extended the comment period on a proposed amendment to Section 25821(a) of Title 27 of the California Code of Regulations, which addresses calculating the exposure level to chemicals listed under Proposition 65 as reproductive toxicants.

The Safe Drinking Water and Toxic Enforcement Act of 1986, also known as Proposition 65, prohibits a company from knowingly exposing any individual to a listed chemical without first providing a "clear and reasonable warning"" to such individual. The law provides an exemption from the need to provide a warning where exposures are below a "safe harbor." Section 25821 requires that exposure be determined by multiplying the “level in question” (i.e., the concentration of a chemical in a given medium) by the reasonably anticipated rate of exposure to that chemical by the average users of a consumer product.

OEHHA first proposed amending Section 25821 on October 5, 2018. At that time, OEHHA proposed: 1) to clarify that where a business presents evidence of the “level in question” of a listed chemical in food based on the average of multiple samples of that food, the level in question cannot be calculated by averaging the chemical’s concentration in foods from various lots; and 2) to require that exposures to reproductive toxicants from consumer products be calculated as the arithmetic mean of the rate of intake or exposure for product users (as opposed to the geometric mean). (For more details on the original proposal, see the PackagingLaw.com article, Comment Period on Calif. Prop 65 Requirements for Calculating Exposure Extended.)

After reviewing the comments received on the October 2018 proposal, OEHHA modified the proposed regulation on July 5, 2019, to state that the concentration of a listed chemical in a food product may be based on the concentration in the product as it is offered for sale to the end consumer, even if the product contains ingredients sourced from different manufacturers or producers. In addition, OEHHA decided not to proceed with the amendment to establish the arithmetic mean as a default in calculating the reasonably anticipated rate of intake or exposure for average users of a consumer product. Comments were originally due by July 12; however, on July 12, OEHHA announced it was extending the comment period to August 5, 2019.