The amount of cocaine in America's largest city containing traces of fentanyl remains low, but contamination is on the rise, according to data obtained by VICE via New York's Freedom of Information Law (FOIL).

Forensic tests on cocaine seized by the New York City Police Department (NYPD) over the last three years show that of 59,364 individual samples, just over one percent—691—contained traces of the super potent opioid.

The figure contradicts a narrative being pushed by health and crime agencies, as well as the White House and much of the media, that drug dealers are routinely lacing cocaine with fentanyl. In 2017, NYC’s health department launched a publicity campaign warning that recreational cocaine users were at "exceptionally high risk of overdose" from fentanyl-laced cocaine, an effort that recently reached bars and clubs in Brooklyn.

It may not be as high as portrayed, but the ratio of cocaine samples testing positive for fentanyl has been edging up, albeit by modest amounts, from 0.4 percent in 2016 to 1.5 percent last year. During the first three months of this year, the ratio was 2.1 percent.

Graphics by Lia Kantrowitz

"This data shows that, although the rise in the rate of contamination is concerning, the accidental cross-contaminating rate is low and purposeful contamination is not happening. So the level of public health concern should remain low," said Professor Dan Ciccarone, a leading authority on the US drug market at the University of California in San Francisco.

Ciccarone said cross contamination rates in the drug trade are inevitable, as they are in other industries. For example, a report by the UK Food Standards Agency found that 8.3 percent of frozen UK chicken and 13.6 percent of frozen non-UK chicken had become contaminated with salmonella, a potentially lethal bacteria.

He said monitoring the situation using detailed drug seizure forensics was a key public health strategy. "Using drug seizure data means we can move from fear-based opinion—for example, that 'fentanyl is everywhere'—to data-driven facts," added Ciccarone.

While the NYPD data, collected between January 2016 and March this year, is useful, he added that positive tests for traces of fentanyl in police labs did not indicate whether or not there was enough of the drug to impact the human body.

"Fentanyl is contaminating small amounts of cocaine. But at what level—is the level of contamination clinically meaningful or worrisome? We need to move from qualitative testing, just knowing the presence of a drug, to quantitative testing, how much of a drug is present," he said. "For example, fentanyl can be detected in nanograms—one billionth of a gram. Yet it is used medically in micrograms, one millionth of a gram. It is lethal at 2mg, one thousandth of a gram, but a million times larger than a nanogram. This huge range shows the importance of quantitative drug testing."

The NYPD data also revealed the number of methamphetamine and ketamine seizures testing positive for fentanyl was on the rise.

In April, a VICE investigation found no concrete evidence of dealers systematically mixing fentanyl into cocaine. Nor did law enforcement data show fentanyl contaminating cocaine outside of the low-end street drug market, where cocaine, including crack, and fentanyl-heroin are more often used together. These users are also more likely to be busted by police than wealthier users, meaning their samples are most likely over-represented in the NYPD's data. It is not wealthy cocaine snorters overdosing from cocaine and fentanyl—it is those from poorer communities using street cocaine with heroin that contains fentanyl.

The NYPD figures fall roughly in line with other cocaine-fentanyl data sets previously reviewed by VICE. In Pennsylvania, the DEA's office tested 30,914 cocaine exhibits seized in the state between 2015 and 2017, of which 0.6 percent contained traces of fentanyl. Testing countrywide also showed that cocaine and fentanyl is a rare mix. Of more than 34,000 samples containing fentanyl seized by police across America and sent to the National Forensic Laboratory Information System (NFLIS) for testing in 2016, 1.4 percent also contained cocaine. And of 2,555 drug batches containing fentanyl tested by the DEA in 2018, 1.1 percent contained only fentanyl and cocaine in combination.

The NYPD data also revealed the number of methamphetamine and ketamine seizures testing positive for fentanyl was on the rise.

Of the 3,582 samples of methamphetamine tested over the three years, 2.2 percent—82 of them—were found with traces of fentanyl. But contamination has increased more steeply than it has with cocaine. In 2016, 0.5 percent of meth samples came up positive for fentanyl, with 2.9 percent in 2017 and 2.2 percent in 2018. In the first three months of this year, it was 4.4 percent.

Methamphetamine is a drug sometimes taken by heroin users and sold on the low-level street drug market, and so may be a case, as with cocaine, of the contamination occurring as a result of sloppy cutting and bagging by dealers.

Yet the results for ketamine, a dissociative anesthetic drug with no established associations to the street fentanyl-heroin trade, are more of a surprise. Fentanyl was found in 8.1 percent of 1,328 samples in the last three years. This high figure was mainly the result of a high proportion of ketamine samples—79 out of 394—which tested positive for fentanyl in 2017. For the first three months of 2019, the ratio had dropped to 3.8 percent. Even so, the mix was not entirely unheard of. Last year someone in Louisiana, Kentucky reportedly overdosed and was hospitalized after taking cocaine and ketamine. Hospital tests on the drugs found the ketamine contained traces of fentanyl.

"The finding that fentanyl is contaminating very dissimilar drugs, such as ketamine, is concerning," said Ciccarone. "Yet again, we need to get quantitative data in order to best advise the drug using public."

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