The problems are that drugs are making it through water-treatment processes to be discharged in “clean” water and sent back into rivers and lakes, and that these drugs can affect aquatic life. The study found cocaine, amphetamines, MDMA, ephedrine, opioids, and more in various water samples from the Grand River watershed in Southern Ontario, “albeit in low concentration.”
When treated water was found to contain drugs, it was usually not in any amount that would affect humans, but fish are much smaller and more likely to be exposed to contaminated water (by dint of their living in water). While most prescription drugs have been tested for their effects on fish, many illegal drugs have not…
All Things Chronic 
I lived in Canada for a while. I’m sad to hear of all the changes and environmental problems they’ve been having. But the water problem is larger and older than even this article will lead you to believe. Frogs were the first to feel the effects of water pollution. There are many years – decades now, probably – of documented frog abnormalities due to water table pollution. It’s only getting worse. The next story will be about how the birds who eat the fish are showing signs of contamination. It WILL work itself up the food chain. Act now!
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I’m not a scientist, but it seems like plastics and pollution are bigger threats to the fish, birds, and water than the drugs. But since humans have agreed to take all these drugs, both legal and illegal, we should be aware of and test for any environmental damage that occurs. Unfortunately, the drug war concentrates on the damage from drugs like opioids and cocaine, when the focus should really be on endocrine disruptors and antibiotics. Those are the drugs that cause deformities like we’ve found in frogs and other amphibians.
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Excellent point!! Thanks for posting such vital information.
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