May 8, 2019 – California NORML has submitted testimony to the state Office of Environmental Health Hazard Assessment (OEHHA) opposing the inclusion of cannabis on the state’s Prop 65 list of known reproductive hazards. Prop 65 requires businesses to post warning signs regarding the presence of substances known to pose a risk of reproductive harm or cancer. Marijuana smoke has already been classified as a carcinogen by OEHHA in spite of human studies showing it doesn’t cause respiratory cancer.
In written testimony, Cal NORML argued that existing scientific evidence on the risks of prenatal cannabis use is unclear, and that warnings are unnecessary in any case because they are already required by current Dept. of Public Health regulations. These require that all cannabis products be labeled, “Cannabis use while pregnant or breastfeeding may be harmful.”
Last month, the OEHHA asked for evidence regarding reproductive toxicity of cannabis, cannabis-related chemicals, marijuana smoke, cannabis extracts, and delta-9-THC. Cal NORML argued that these terms aren’t chemically well defined, since cannabis and its extracts contain many ingredients, such as CBD, THC acid, CBD acid, THCV, CBG, CBN, and dozens of terpenes, which have never been studied for reproductive effects.
To date, the only human pregnancy studies that have been conducted involve women who smoked marijuana during pregnancy. However, smoking is already a known risk factor for reproductive harm. No human study has ever been conducted using cannabis edibles, vapes, extracts, or cannabinoids other than THC. Those studies that have looked at marijuana use during pregnancy have come to conflicting results. Some have concluded that marijuana smoking during pregnancy is linked to low-birthweight babies, while others have not. A recent meta-analysis of 31 studies found maternal marijuana use during pregnancy is not an independent risk factor for adverse neonatal outcomes, and that such associations as have been alleged may be attributable to tobacco use and other confounding factors.
In light of the inconclusive evidence, Cal NORML argues there are no grounds for new Prop 65 hazard warnings. Given that state regulations already require warnings against cannabis use during pregnancy, Cal NORML recommends that future warnings be coordinated by the Dept. of Public Health and Bureau of Cannabis Control, who oversee cannabis regulations. “Further OEHHA warnings at this point would be unwarranted and likely to confuse matters,” says Cal NORML director Dale Gieringer. “California consumers are already bombarded with so many vague and unfocused Prop 65 warnings that they tend to tune out and ignore them, and the cannabis industry has enough to worry about without more superfluous regulations.”