Despite its hippie associations and "all-natural" branding, the cannabis industry has been using pesticides for decades. Legal cannabis was supposed to bring pesticides to safe levels but that doesn't necessarily mean consumers will be safe from the negative effects of pesticides — especially since state inspection programs aren't fool-proof, and there is little research on how inhaling pesticides, clinging onto marijuana bud, affect your health.
As Elise McDonough from High Times put it back in 2017, “Anyone who smokes cannabis, black-market or otherwise, is unwittingly participating in a huge uncontrolled experiment involving millions of human subjects.”
She’s not exaggerating. Pesticides have been a problem even for legal cannabis products in places like Oregon, Colorado, California, and Washington. Even Massachusetts with it’s 100 percent ban on pesticide use has experienced infractions.
One common pesticide used in cannabis cultivation is the insecticide bifenthrin, which is classified by the Environmental Protection Agency (EPA) as a possible human carcinogen. Another one, acephate, is neurotoxic to humans, is a possible carcinogen, and a potential endocrine disruptor. Meanwhile when the fungicide myclobutanil is heated up, it changes into hydrogen cyanide — a very poisonous and flammable liquid.
In 2013, a study in the Journal of Toxicology analyzed the potency of pesticides in legal marijuana at a medicinal dispensary in California. Researchers found that many of the chemicals present on cannabis buds were directly transferred into marijuana smoke and that the chances of pesticide exposure through cannabis smoke was high. But if you think this is just about flower, think again. Concentrates, like oil used in vapes, are no better and may be worse because when concentrating cannabis, you're also getting a higher concentration of pesticides.
While growers and regulators work things out, consumers need to take precautions, especially patients with impaired immune systems. Here are steps you can take:
1) Look at the packaging for organic certification stamps. These private certification programs have stepped in to fill the void that federal agencies have left behind. If you don’t see an organic certification stamp, demand that your dispensary carry certified products. Some certification programs include: Clean Green, Certified Kind, OMRI (Organic Materials Review Institute), California’s OIM (Organic Input Materials) Program, and Oregon-based Organic Cannabis Growers Society. Keep in mind that it’s not known if the benign organic materials these programs allow—neem, kelp, garlic, rosemary, fungicides, or bone meal—are safe to inhale, but they’re likely less carcinogenic.
2) Avoid cloned pot. Because cannabis buds can get contaminated systemically, clones taken from a mother plant that has absorbed pesticides will have small but significant concentrations, as well. Stick with cannabis grown from seed.
3) Try gastro-edibles. While it’s still not great to eat pesticides, your liver at least adds some extra protection that you don't get when you inhale them. This is not true for edibles you take orally as drops for quick absorption. It’s only the case for extracts put into your food or beverages.
As alarm grows, states have begun to implement tighter and more evidence-based restrictions on growers and dispensaries. For example, California has already shown improvements and Washington state now has a certification program regulated directly by a state department of agriculture.
Regardless, they are moving slowly and it still pays to be cautious. Know your grower and, if you’re not sure, have a gastro-edible instead.