According to University of Toronto study published in the Atmospheric Pollution Research journal, air pollution could be spreading up to three times farther than previously thought. This could change how we have to think about the effects of infrastructure design on public health. Past research on air pollution from vehicle tailpipes has shown poor air quality anywhere between 100 to 250 meters (330 feet to 800 feet) of major roadways. The UT researchers have found that concentrations of pollutants from traffic are still double at a distance of 280 meters (920 feet) downwind from highway 400 north of Toronto. According to Health Canada, “poor air quality from traffic pollution is associated with a number of health issues, such as asthma in children and other respiratory diseases, heart disease, cancer and increased rates of premature death in adults.” The Canadian Medical Association attributes 21,000 premature deaths each year (!) in Canada to air pollution.
— source treehugger.com