It’s a fact, isn’t it? Every car’s emissions contribute to pollution. Not so fast… a team of inquiring Canadians have coughed up some useful clarification. Most of the pollution comes from a fraction of the traffic. More like 1 in every 4 cars produce the vast majority of harm.


Autoblog turned us on to some eye-opening studies by researchers at the University of Toronto. They reveal almost all automotive pollutants come from a fraction of total vehicles. The lethal 25% contribute 95% of black carbon, 93% of carbon monoxide. Plus 76% volatile organic compounds that are known-carcinogens.

And which are the evil minority? Older cars, badly tuned cars, and whether the driver is heavy-footed and erratic.

The researchers also found that the impact of pollution extends much farther from a major roadway than initially thought. Poor air quality is now being detected from as far as 300 yards (3 football fields) from a major roadway. A major roadway doesn’t have to be a 10 lane superhighway… a modest four-lane street with steady traffic could qualify.

Who doesn’t live within that radius? Looks like it’s time to move to Duluth and become wind farmers. Click on the CLEANEST CITIES IN THE US to see which are.