California’s New Safe Harbor Regulations Warn That Cannabis During Pregnancy Can Affect Child Birthweight, Behavior, and Learning Ability

News & Events

November 1, 2022


California’s New Safe Harbor Regulations Warn That Cannabis During Pregnancy Can Affect Child Birthweight, Behavior, and Learning Ability

As of October 1, 2022, California has adopted new safe harbor warnings for cannabis under Proposition 65. These warnings provide language on the potential adverse effects of prenatal cannabis exposure and may have implications for certain cannabis product manufacturers and businesses.

The California Office of Environmental Health Hazard Assessment (OEHHA) has issued new regulations regarding specific safe harbor exposure warnings, particularly during pregnancy. The regulations state that certain cannabis products and businesses need to include new safe harbor warning language in their labeling and/or signage in order to maintain compliance under California Proposition 65.

OEHHA’s new safe harbor warnings apply to cannabis products with the potential for exposure to cannabis smoke or delta-9-tetrahydrocannabinol (delta-9-THC) via inhalation, ingestion, or dermal application. Further, the new warnings apply to potential environmental exposures to cannabis smoke or delta-9-THC from businesses where delta-9-THC is smoked, vaped, or dabbed (i.e., inhaled in small quantities).

The new safe harbor warnings for cannabis are unique, as they include specific language regarding potential adverse effects from cannabis exposure during pregnancy. For example, to maintain compliance, cannabis products intended to be smoked need to warn consumers that the State has determined that smoking cannabis increases cancer risk and during pregnancy exposes a child to delta-9-THC and other chemicals that can affect the child’s birthweight, behavior, and learning ability. This updated language may reflect a change in OEHHA’s approach for labeling certain products under Proposition 65, where greater detail may be required in warnings. Further, OEHHA determined that use of the popular short-form warning for cannabis products is insufficient because it “does not provide the level of specificity needed for cannabis (marijuana) smoke and delta-9-THC exposures.” OEHHA continues, stating that the new safe harbor warning language “clearly conveys the adverse developmental effects cannabis smoke and delta-9-THC can cause when used by pregnant women.”

OEHHA allows for a one-year transition period for businesses to label their products with compliant warnings. OEHHA also states that businesses are free to substitute their own warning language for the agency’s wording; however, the use of OEHHA’s language is a defense against claims that other warning language does not meet the “clear and reasonable standard.” This suggests that certain businesses may risk non-compliance if they choose to develop their own safe harbor warning.

For more information, refer to OEHHA’s website and/or contact Gradient.

Topics:  Cannabis, Delta-9-THC, Pregnancy, Proposition 65, Product and Consumer Safety


Steven Boomhower, Ph.D.
Senior Toxicologist

Tom Lewandowski, Ph.D., DABT, ERT, ATS

Kim Reynolds Reid
Principal Scientist

James Rice, Ph.D.
Senior Environmental Scientist