Fish exposed to treated wastewater have altered behavior

Science Daily –

A team of researchers from Environment Canada and Climate Change Canada and McMaster University have found that fish living downstream from a wastewater treatment plant showed changes to their normal behaviour — ones that made them vulnerable to predators — when exposed to elevated levels of antidepressant drugs in the water.

The findings, published as a series of three papers in the journal Scientific Reports, point to the ongoing problem of prescription medications, personal care products and other drugs that end up in the watershed and the impact they have on the natural environment.

“Fish can be seen as the canaries in the coal mine,” says Sigal Balshine, a professor in the Department of Psychology, Neuroscience & Behaviour at McMaster and one of the authors on the papers. “The fish that make their homes in the receiving waters downstream from wastewater treatment plants absorb these chemicals and therefore can be our water sentinels.”

For their research, the team caged gold fish at various sites in Cootes Paradise watershed — designated as a Great Lakes Area of Concern by an international environmental commission — and at a control site in Jordan Harbour, which is located between Beamsville and St. Catharine’s on the shores of Lake Ontario.

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