Air pollution kills people — even with new, stricter standards on emissions, according to a study released Tuesday.
The survey of more than 500,000 Americans shows that as air pollution levels rise in the areas where they live, rates of death rise. The researchers have even shown that as levels of certain pollutants in the air go up, rates of death go up — especially deaths from heart disease.
"Our data add to a growing body of evidence that particulate matter is really harmful to health, increasing overall mortality, mostly deaths from cardiovascular disease, as well as deaths from respiratory disease in nonsmokers," George Thurston of New York University's Langone Medical Center, who led the study, said in a statement.
The study involves air pollutants called particulates, in this case tiny particles 2.5 micrometers or less. They can settle deep into the lungs and are not coughed up like grit might be. They also often consist of dangerous heavy metals such as mercury or arsenic.
The team used a survey run by the National Institutes of Health and AARP, looking at more than 500,000 volunteers aged 50 to 71 in six states and two large cities, Atlanta and Detroit. They used Environmental Protection Agency data that breaks down exposure to air pollution by county or city.
Every extra 10 micrograms per cubic meter of air raised the risk of heart death between 2000 and 2009 by 10 percent, they report in the government journal Environmental Health Perspectives. And that tiny increase in air pollution raised the overall risk of death over the decade by 3 percent.
People who are poorer and less educated often live in more polluted areas and also have higher death rates, so the researchers accounted for that, along with age, race, marital status, smoking, weight and alcohol use. The effects held even when those other factors were considered.
"We need to better inform policymakers about the types and sources of particulate pollution so they know where to focus regulations," said Richard Hayes, a professor of population health and environmental medicine at NYU Langone who also worked on the study. "It is especially important to continue monitoring health risks as national standards for air pollution are strengthened."