In the week leading up to 4/20 — wherein thousands of cannabis enthusiasts gathered in Golden Gate Park to smoke pot — the San Francisco Police Department distributed a disturbing narrative to the media.

“Last year, we had numerous attendees pass out from using marijuana laced with fentanyl,” SFPD Captain Una Bailey wrote in a statement. “Fentanyl is one of the strongest opiate drugs on the market, being 50 to 100 times stronger than morphine. A tiny bit too much can be fatal.”

It’s a serious claim. If there were fentanyl discovered in marijuana in S.F., that would be news-worthy — if for no other reason than it’s never been documented anywhere, nationwide. The Drug Enforcement Administration even said so in a report from March.

But in trying to track down the evidence behind this fentanyl-laced marijuana, SF Weekly got stuck. The Department of Public Health — which, in response to our inquiries, both SFPD and the San Francisco Fire Department directed us to — monitors the annual number of fatal overdoses citywide. They told us that there were no confirmed fentanyl overdoses at Hippie Hill on 420 in 2018 (or, for that matter, in 2019).

There’s a good reason why this is false: Fentanyl has a really low combustion point.

“You literally can’t smoke it directly,” says Eliza Wheeler of the Harm Reduction Coalition. “When people smoke fentanyl, which many people do, you have to smoke it on foil. You cannot put a flame directly to the drug. If you sprinkle it on a bud it destroys the actual drug by burning it. It’s not even actually possible to get high from smoking it that way.”

Wheeler has reached out to SFPD several times about the spread of misinformation, but Bailey’s newsletter is still up. SF Weekly has also reached out to her directly to verify her claims, but didn’t hear back.

If this seems like a standard case of cops not knowing what they’re talking about when it comes to drugs, well, it is. But spreading misinformation can have sweeping health impacts. After claiming fentanyl-laced marijuana caused overdoses in 2018, Bailey then added that, “When dealing with a fentanyl overdose, the first responder treating the individual is also at risk as the fentanyl can be absorbed through the skin.”

Multiple drug experts have disproven this claim about absorption through skin contact. Citing an American College of Medical Toxicology study, the Harm Reduction Coalition states that “opioid toxicity (i.e., “overdose,” or respiratory depression) from transdermal and airborne exposure to Illicitly Manufactured Fentanyl (IMF) is a near scientific impossibility.”

Further, it appears that once misinformation about drug use has been spread, the city doesn’t seem interested in correcting itself. If, for example, SFPD inaccurately warned of a measles risk at a massive event with no traceable evidence to that effect, the Department of Public Health would no doubt respond quickly, asking them to issue a correction.

At the end of the day, false information about drug use is more harmful than some baseless urban legend about razor blades in Halloween candy.

“The fentanyl hysteria has many layers of problematic consequences far beyond a bunch of stoners being nervous about their drugs. It weaponizes fentanyl, and when you weaponize a drug that by default creates a weapon-wielder — and those people are even further demonized,” Wheeler says. “This whole narrative of these ‘bad actors’ poisoning everyone, poisoning innocent cannabis smokers on 420 is not true. No one is going to go to kill 15,000 potheads.”

And, she adds, it’s distracting. “You have a whole city of people Downtown who are using fentanyl, and we’re working really hard to make sure they don’t die.”