Police in Alberta are warning residents about W-18, a powerful opioid 100 times stronger than fentanyl, discovered during a drug bust last summer.
Calgary police said 110 fentanyl pills were seized from a home in Rocky View County in southern Alberta in August.
In December, tests from Health Canada confirmed three pills contained W-18.
"It's an ongoing concern based on the fact W-18 is 100 times more toxic than fentanyl," Martin Schiavetta, a staff sergeant with the Calgary Police Service Drug Unit, told Global News. "And we already know the deadly consequences fentanyl has."
The drug comes from a "W-series" of opioid compounds first discovered at the University of Alberta in 1982, according to the B.C. Centre for Disease Control. There are 32 compounds, W-1 to W-32, with W-18 being the most toxic.
W-18 is not currently regulated under the Controlled Drug and Substances Act and can be manufactured and bought freely, according to the B.C. Centre for Disease Control.
Mike Turner, with the Alberta Law Enforcement Response Teams, says while other cities haven't come across the drug it's a concern for the whole province.
"If it's surfaced in Calgary in fentanyl then it's something all our police agencies have to be cautious of," said Turner.
Staff Sgt. Schiavetta says W-18, like Fentanyl, is being produced in China with a majority of the drugs coming through ports in B.C.
"There is no way to really reduce the supply side because it's being produced in a foreign country," he said. "We really have to focus on the demand side, through awareness education and prevention."
Warnings about W-18 come in the wake of a spike in fentanyl deaths that raised alarms from law enforcement and health agencies across country.
Alberta Health said there were 213 fatal fentanyl overdoses in 2015 up from 120 fentanyl-related deaths in 2014. In 2011 there just six deaths reported.
The BC Corner Services says fentanyl killed about 90 people in British Columbia between January and August this year.
In response to the rapid increased in fentanyl related deaths Alberta Health Services announced Tuesday there will be expanded access to naloxone, a medication that aids in reversing the symptoms of an opioid overdose.
Health Canada is also proposing amendments to its prescription drug list that could make naloxone available without a prescription by the spring.
However, due to the strength of W-18 there is little evidence to suggest naloxone would have an effect in treating an overdose, the BC Centre for Disease Control says.
In Ontario, clusters of heroin overdoses in several cities have led to increased warnings from police about bootleg fentanyl.
The Waterloo Region say there were six overdoses between Jan. 23 and Jan. 26, with one of them being fatal. Heroin was a factor in five of the cases and fentanyl is suspected in at least one case. The Kingston Community Health Centres said there were four non-fatal overdoses and one fatal overdose reported between Jan. 23 and Jan. 28 in the Kingston area, with 3 cases possibly involving fentanyl.
Michael Parkinson, a spokesperson for Waterloo Region Crime Prevention Council, says it's hard to say if W-18 has reached Ontario because of a lack of timely toxicology reports.
"When it comes to prescription opioid consumption Canada leads all nations in the world. The U.S. is number two," he said. "There should be no surprise that we are now at crisis levels of opioid addiction and death."