Medication Present in St. Lawrence River

Chemotherapy products and certain hypertension and cholesterol medications are present in the St. Lawrence River.

A study conducted by Université de Montréal researchers reveals that downstream and upstream water from the Montreal wastewater treatment plant contains bezafibrate (cholesterol reducing medication), enalapril (hypertension medication), methotrexate and cyclophosphamide (two products used in the treatment of certain cancers). Only bezafibrate and enalapril, however, have been detected in the treated water leaving the wastewater treatment plant and in the surface water of the St. Lawrence River, where the treated wastewater is released.

A significant proportion of the drugs consumed are excreted by the human body in urine and end up in municipal wastewater. Chemotherapy products, such as methotrexate, are excreted by the body practically unchanged (80 to 90 per cent in their initial form).

The pharmaceutical compounds studied were chosen because of the large quantities prescribed by physicians. “Methotrexate and cyclophosphamide are two products very often used to treat cancer and are more likely to be found in water,” says Sébastien Sauvé, a professor of environmental chemistry at the Université de Montréal. “Even though they treat cancer, these two products are highly toxic. This is why we wanted to know the extent to which the fauna and flora of the St. Lawrence are exposed to them.”

The study was published in the Journal of Environmental Monitoring and produced by researchers from the Department of Chemistry of the Université de Montréal and the Environment Canada Aquatic Ecosystem Protection Research Division. It was funded by the Natural Sciences and Engineering Research Council of Canada, the National Council for Science and Technology of Mexico, the Canada Foundation for Innovation, the St. Lawrence Action Plan and Health Canada’s Chemicals Management Plan.