The new villain in the opioid drug crisis sweeping Canada, often with deadly results, fentanyl is now showing up in London added into other drugs, including marijuana, authorities are warning.

Urine tests conducted on people who reported using only heroin or smoking pot tested positive for the powerful drug, the London area’s public health office reported Thursday.

One pot activist said he’s skeptical that fentanyl is being cut into marijuana, but officials were taking no chances after the tests, issuing a rare warning involving police and three different health agencies.

“Finding fentanyl in drugs like marijuana means that people who think they are doing something minor may end up dying of overdose,” Dr. Chris Mackie, the region’s medical officer of health, stressed.

The urine tests were run this week at Addiction Services of Thames Valley’s London treatment clinic.

The Middlesex-London Health Unit also says there have been reports that fentanyl — a drug 100 times more powerful than morphine — has hit the streets in powdered form in London and is being snorted like cocaine.

The spectre that potentially deadly fentanyl is being cut into other street drugs, contaminating even marijuana, should be an extra wake-up call to those who use illegal drugs without knowing what they might contain, officials with the health unit, addiction treatment service, Canadian Mental Health Association and London police said.

“Users have no way of knowing what they are ingesting and too often the results are tragic,” said London police Chief John Pare. “Recently, our police service has found that many illicit drugs have traces of fentanyl in them.”

Smoking marijuana is seen as harmless by many, especially with the federal Liberal government moving on an election vow to make recreational use of pot legal by July 1, 2018.

But since ingesting even small amounts of fentanyl can be fatal, authorities are worried.

“When people use illicit drugs, there’s no way to know exactly what they’re doing,” Mackie said.

London marijuana activist Eric Shepperd said he’s skeptical that marijuana is being contaminated by fentanyl.

“I’m not sure if the report here is necessarily accurate by those who reported smoking only marijuana. They may have done something else and are just declining to speak about it. That does happen from time to time,” he said.

Shepperd said he’s never heard of fentanyl being found in marijuana.

“It’s always been an urban myth. It’s always been something you hear from overly concerned people about cannabis and not knowing what’s in it,” he said.

Dr. Mike Hart, who operates the Ready To Go medical cannabis clinic in London, said he’s never heard of a case where fentanyl has been put in marijuana.

“I’ve never heard of this happening before. I think it could possibly be difficult to detect in someone who’s an inexperienced user because you’re not sure if you’re feeling different because of the cannabis or feeling different because of the fentanyl,” he said.

“The safest way to get cannabis is to go to a medical clinic . . . and to get a physician to prescribe you cannabis that’s specifically for you and is the right ratio and the right strains.”

jbieman@postmedia.com

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