Friday Favorites: Pesticides in Marijuana

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

California was the first state to legalize medical marijuana. When labs started reporting they were finding high levels of “pesticide residues,” the LA city government “covertly acquired and then tested” three samples from dispensaries, and found that two of the three samples had “exceedingly high levels” of a pesticide—up to a thousand times the legal limit.

Yeah, but how much ends up inside the consumer? Only about 10 percent or so of the pesticides in tobacco make it through a filtered cigarette, which was found to be comparable to using cannabis in a water pipe with filters attached. But use a regular bong, and about half the pesticides end up in your lungs. And, a glass pipe is even worse. Because most users don’t attach a carbon filter to their bongs with seven and a half grams of activated charcoal, “in general the portion of pesticide recovery [from cannabis would be] alarmingly high and is a serious concern.” Although we don’t know “precisely how damaging these chemicals are, the fact they are present in smoke at such high levels should be concerning.” “Considering these results, high pesticide exposure through cannabis smoking is a significant possibility, which may lead to further health complications in cannabis consumers”—especially if we’re talking about medical marijuana. Sick, vulnerable people, potentially making things worse.

“[T]he potential of pesticide and chemical residue exposures to cannabis users is substantial and may pose a significant toxicological threat in the absence of adequate regulatory frameworks.” Okay, so what are states doing about it? Colorado recently suffered some “high-profile recalls of…marijuana batches” contaminated with “harmful pesticides” that made it into some of the edibles. Evidently, “growers sometimes find themselves…overwhelmed by pest issues [and] resort to nuclear tactics”—trying anything to protect their crop. This has created “a public safety threat,” with “intensified toxicity in concentrated products of particular concern.” “[P]esticide levels were [found to be] approximately 10x higher in concentrated cannabis products,” like the oils and waxes sometimes used in edibles or dabbed as concentrates.

“A study of pesticide use on cannabis crops in Oregon” found a similar problem. A survey of samples off store shelves in Washington state found five out of six contaminated, “including [with] potentially neurotoxic and carcinogenic agents.” “Many [samples] harbored multiple contaminants, attaining levels” basically off the chart, including “24 distinct pesticide agents,” insecticides, fungicides—none of which are approved for use on cannabis. But, it’s not their fault—the EPA hasn’t approved any because it’s still a federally illegal crop. In fact, testing labs in California have “become hesitant to publicize their service or list agents for which they could [test], as they suspected that such information” might just be used as an instruction manual by unscrupulous growers to seek out even more toxic agents.

Okay, so just regulate it. They’ve tried, but guess what the biggest barrier was they came up against? Surprise, surprise, the cannabis industry—the multi-billion-dollar cannabis industry. Like the tobacco industry before it, “the cannabis industry is attempting to weaken pesticide regulations.” “Reportedly, the Colorado Department of Agriculture…initially hoped to limit permissible pesticides to the most nontoxic,” but this proposal was quashed by industry pushback, just like the tobacco industry was able to do.

Big Tobacco “has provided a detailed road map for” King Cannabis: “deny addiction potential, downplay known adverse health effects, create as large a market as possible as quickly as possible, and protect that market through lobbying [and campaign contributions].” “[B]olstered by enormous profits,” the tobacco industry was able to get itself “exempted from every major piece of consumer protection legislation.” So that should be a cautionary tale for us now, given that public health advocates have definitely fewer billions to work with.

Big Tobacco may not just be providing the roadmap, but waiting in the wings to own the road. “As a result of [lawsuits] against the tobacco industry, more than 80 million pages of internal company documents became available.” And what they reveal is “that since at least 1970, despite fervent denials, major multinational tobacco companies” like Philip Morris having been scheming, willing, and prepared to enter the legalized marijuana market to become Big Blunt. “Because of the tobacco industry’s demonstrated ability and willingness to modify its products to increase addictiveness, obfuscate information, deceive the public, and…target vulnerable groups to increase demand, the industry also has the power to dramatically change [the game.]”

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Image credit: Andrea via Adobe Stock photos. Image has been modified.

Motion graphics by Avocado Video