AIR POLLUTION: Study links premature deaths to traffic emissions (05/01/2009)
Robin Bravender, E&E reporter
People who experience chronic exposure to traffic-related air pollution are more likely to die sooner than those with lower exposures, according to a recent study.

Those with higher exposure to nitrogen oxide (NOx) are 17 percent more likely to die for any reason and 40 percent more likely to die from circulatory disease, according to a study published today in the journal Environmental Health Perspectives.

Nitrogen oxides form when fuel burns at high temperatures, such as in motor vehicle engines. Mobile sources like diesel trucks, cars and motorcycles are responsible for more than half of all U.S. NOx emissions, according to U.S. EPA.

Researchers from Canadian universities, the Canadian government and the University of California, Berkeley, studied the correlation between exposure to NOx and premature death at locations across Toronto between 1992 and 2002.

Their findings add to a growing body of evidence that traffic-related air pollution substantially raises the risk of premature death, said Michael Jerrett, the study’s lead author.

These are fairly large risk estimates for anyone living in a big city anywhere in the world, Jerrett said.

Because the study’s 2,360 subjects were drawn from a respiratory disease clinic in Toronto, the high prevalence of heart disease probably limits the findings to populations with high numbers of susceptible individuals, the report notes. However, the large risks uncovered here and in other studies implicate traffic-related air pollution as a public health risk, the study says.

“Across many different societies, we’ve seen significant improvements in the emission controls for automobiles,” Jerrett said, noting that the health risks posed by traffic pollution could grow more serious.

“The number of cars and trucks on the road is going up at a nearly exponential rate, particularly in the developing world,” he said. “These exposures are likely to go up, and they’re going to affect large populations.”

Click here to read the study.