Human waste could be feminizing fish in St. Lawrence

CBC reported last week that researchers from l’Universite de Montreal have found concentrations of estrogen 90 times the normal rate in the St. Lawrence River, just downstream from the Island of Montreal.
Sebastien Sauve, a professor of environmental chemistry at the university, said that researchers have found high levels of both naturally occurring estrodiol, and synthetic estrogenic compounds common in hormone replacement therapy medications taken by women.
Scientists at the Quebec’s National Institute for Science Research, who are studying the effects on fish of excessive hormones in the water, found that one third of the males of a common species of minnow downstream from Montreal had ovaries growing in their testes.
The belief is that the high estrogen levels in the St. Lawrence water might be from human waste. Other possible sources are said to be byproducts of plastics as they break down, or effluent from pulp and paper mills.
Montreal is planning to add ozonation at its wastewater treatment plant and is hoping the process will destroy the hormones and other pharmaceuticals.