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Black Death: Why SF's Street Heroin May Soon Become Even More Dangerous

From Mexican black tar heroin to “Colombian mimic”: how a Latin American peace treaty could mean more overdose fatalities.

Actual size of one $10 hit of black tar heroin.

This story is part of our special report on the private tragedies and public toll of our injection drug epidemic. 
Read more of One City, Under the Syringe here.


The heroin sold in 2017 San Francisco is mostly the same low-grade stuff that has ruled the streets since the mid-1980s: so-called black tar heroin, a crude, sticky, and relatively unrefined dark-brown opiate grown and processed in Mexico. But there are signs that a higher-quality product could be hitting the streets—and if it does, experts say, the city’s injection drug problem could get a lot more deadly.

Dan Ciccarone, a UCSF School of Medicine professor who has studied local and national heroin use extensively, says that for three decades, almost all heroin in San Francisco has been of the black tar variety. By contrast, in the Midwest and on the East Coast, powdered heroin—more refined, and more powerful—has dominated the market.

Ciccarone speculates that this division between black tar and powdered heroin resulted from high-level agreements worked out in the 1980s between the Colombian drug cartels, who controlled the illicit trade east of the Mississippi River, and their Mexican counterparts, who controlled the territory west of it. The Colombians sent their higher-grade powdered heroin to the east; the Mexicans, who hadn’t yet mastered the refining process, sent black tar to the west. But the status quo changed during the long peace negotiations between Colombia’s FARC guerrillas and the government, which concluded this June. One result of the negotiations was that the guerrillas stopped producing heroin for the cartels. Mexico stepped in to fill the void. Thanks to what Ciccarone calls a “technology transfer” in which the Colombians taught the Mexicans how to refine their heroin, Mexican cartels replaced the high-quality East Coast powdered heroin with a similar product. However, that new product hasn’t yet been available on the West Coast. “San Francisco seems to be a little stuck in time, which is good,” Ciccarone says. “My theory is that we simply don’t get heroin from that supply chain.”

Why is it good that San Francisco has been “stuck” with black tar heroin? One word: fentanyl. Starting around 2013, traffickers across the country routinely began adding the synthetic opioid to heroin to increase its potency. Because fentanyl is so strong (it’s 40 to 50 times more powerful than heroin, which itself is three times stronger than morphine), even a tiny amount can cause a fatal overdose. (Making matters worse, the fentanyl that’s added is often bootleg and can contain dangerous impurities.) According to federal drug seizure data, overdoses caused by fentanyl and other synthetic opioids doubled between 2013 and 2016, with approximately 64,000 deaths in the United States. The sudden appearance of fentanyl (both in heroin and in pill-form opioids like knockoff OxyContin), the doubling of the number of heroin users nationally since 2008, and a drop in heroin’s price are the three factors primarily responsible for the national opioid overdose crisis.

So far, San Francisco has been largely shielded from that developing crisis for a simple reason: The black tar heroin that still dominates the streets here is much harder to cut with fentanyl than powdered heroin is.

But the city’s relative immunity from the overdose crisis that has devastated much of the country may be ending. “There have been reports over the last couple of years of a gray powdered heroin,” Ciccarone says. He hasn’t heard if it’s what the DEA calls a “Colombian mimic”—“because the Colombians taught the Mexicans how to make it”—but Holly Bradford, who as head of the San Francisco Drug Users Union (a needle exchange with more than 1,000 participants) has an unsurpassed connection to the street, thinks it might be. “People say they’re seeing more and more powdered heroin on the streets,” she says. One user says it’s available in Civic Center. If powdered heroin becomes easily available here, and is as widely adulterated with fentanyl as powdered heroin is elsewhere, the toll of overdoses in San Francisco is sure to rise.


Originally published in the October issue of San Francisco

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