Photo: Environment Canada

Photo: Environment Canada

Most people who fish like a good tussle. But those who prefer less aggressive quarry might try wetting a line downstream from an ethanol plant. A new study of 19 sites in Minnesota and Iowa shows that the production of biofuels can put plant-based estrogens into the water of the sort that have been linked to feminization in fish. Effluents from other plant-based industries showed similar results, mimicking female hormones that can cause fish populations to collapse. And not all rural wastewater treatment plants are up to the task of removing the hazards.

Civil engineering research led by Prof. Paige Novak at the University of Minnesota found plant-based estrogens, known as phytoestrogens, in surface water downstream from industrial sites in eight of 19 cases.

Novak’s study found phytoestrogens at environmentally-relevant levels not only around biofuels manufacturers, but also near a soy milk factory, a barbecue meat processing facility and a dairy.

Treatment plants appear to be capable of removing the compounds, but water leaving one of the three plants Novak tested still had enough phytoestrogens to damage fish.

The study, to be published in the journal Environmental Toxicology and Chemistry, doesn’t identify the names or locations of the production or treatment facilities tested.

In Novak’s view, “Our nation needs to do some careful planning as we rapidly expand various plant processing industries.”