Deaths Increase as Air Pollution Levels Rise
Then they matched the pollution data with death rates in those cities during the following 24-hour period, excluding all deaths caused by accidents, suicide and homicides. What the researchers found was that for every increase in PM10 levels, there was a 0.5% increase in the number of deaths. The largest increase was seen in deaths from cardiovascular and respiratory diseases. They also noted a small increase in deaths that they could attribute to a rise in ozone level.
Among the locations studied were six areas in California: Los Angeles, Oakland, Santa Ana-Anaheim, San Bernardino, San Diego, and San Jose, and three in Texas: Dallas-Fort Worth, Houston, and San Antonio. In addition, Atlanta, Chicago, Cleveland, Detroit, Miami, Minneapolis, New York, Philadelphia, Phoenix, Pittsburgh, and Seattle were included. All told the study encompassed more than 50 million people.
"What this provides is a national perspective on air pollution and its health effects," Samet tells WebMD. "Those who are most at risk are ... likely to be frail and have advanced heart and lung disease. The surprise in this data, and I do think I have been relatively conservative in interpreting the data, is that while we have gotten rid of our smoke stacks, we are still seeing health effects. We are taking the science and putting it together in a way that policy makers can pay attention to and it is important for them to pay attention to this."
Samet adds that the problem of particulate pollution is more pressing than global warming. "The contrast with global warming is we will always be deciding what to do based on models and projections and schedules that really exceed our lifespan. Here it is more immediate and we have evidence of effects."
"This is an important study because of the extreme thoroughness of their examination and their exhaustive analysis. It should convince some of the doubters," says Morton Lippmann, PhD, a professor of environmental medicine at New York University School of Medicine and a member of an EPA advisory committee on particulates.
As a cause of death, particulate pollution "is not in the same category as smoking and traffic accidents but it is bigger than radon in terms of [deaths]. It is analogous to, and larger than, environmental smoke," Lippmann says.