Heavy traffic is often associated with air pollution but a new study from the University of Toronto suggests it’s a major contributor to water pollution, too. The study, published in the journal Environmental Research Letters, found that chemicals commonly used in vehicle fluids, tires and paints were much higher in rivers next to roads with heavy traffic. “We found a strong relationship between traffic and the concentration of these chemicals,” says Tife Awonaike, a recent PhD graduate from the department of physical and environmental science at U of T Scarborough who is lead author of the study.