Deaths Increase as Air Pollution Levels Rise
Dec. 13, 2000 -- A daily stroll or jog through the park might be just what the doctor orders some people not to do, especially if they live in big cities. Scientists who study air pollution have been amassing information that shows tiny airborne particles are causing deaths and illnesses, particularly among older people. The most recent study about this kind of air pollution appears in the Dec. 14 issue of the prestigious New England Journal of Medicine.
Although it may be hard to accept that the air many of us breathe is downright dangerous, the fact remains that it is, according to the new study. John Vandenberg, PhD, the director of the National Research Program for Particulate Matter for the Environmental Protection Agency, doesn't mince words on the subject: "You can see with these large-scale studies [that] ... low levels of pollution are affecting the population. This probably translates into thousands of people having an early death every year, or tens of thousands of people," he tells WebMD.
Polluted air can contain nearly invisible "particulate matter" -- droplets or specks caused by vehicle gases, power plants, waste disposal facilities, fires, and industrial plants. Since 1987, the EPA has sought to monitor and limit particles that are smaller than 1/100ths of a millimeter, or 10 microns, called PM10 because of their dimensions. In addition, even smaller particles called PM2.5 have been regulated since 1997.
Previous studies have shown that PM10 particles are causing illnesses that are shortening people's lives; those with lung and heart disorders are most affected by this pollution. Experts tell WebMD that this newest study provides the strongest and clearest evidence to date that air fouled by these particles is also a killer. One expert said more people die from these particles every year than from second-hand smoke or exposure to radon.
The study was conducted by Jonathan Samet, MD, MS, professor and chairman of the Department of Epidemiology at the Johns Hopkins University School of Public Health, and his colleagues there. They analyzed specific, hourly readings on levels of ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide, as well as levels of PM10, for a 24-hour period in the 20 largest U.S. cities.