Insp. Howie Page says two men in their early 20s accidentally overdosed and were hospitalized due to use of such drugs, which are meant for research purposes and not recreational use.
He says police believe the victims purchased the drugs online and took them because they thought their effects would be similar to those of cocaine or ecstasy.
Police say the substances, which can be snorted, smoked, injected or diluted in a liquid, are not controlled by the Controlled Drugs and Substances Act.
But they want people to know that the drugs (sold as ethylphenidate and methylbenzypiperazine) may be fatal to some and in fact, many of the packages are labelled as "not for human consumption."
Page says people may have a "false sense of safety" when they read things from unknown sources on the Internet advising them on the use of certain drugs.
"Consumers have no way of knowing if the substance received is actually the substance which it's purported to be," he said, adding there could also be issues with the purity or concentration of a drug or how it reacts with alcohol.
"The bottom line is, we don't want a death," he said.
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