A recent national study showing airborne soot remains a significant health hazard for women was based in part on data collected in Pittsburgh, where such pollution remains dangerously high.
Published in the Feb. 1 edition of the New England Journal of Medicine, the study used data from 65,893 post-menopausal women collected for the Women's Health Initiative, a well-respected research project that earlier had shown risks of hormone supplement to women's heart health. The new study found that women with higher concentrations of fine particulates in the air near their homes have increased risks of fatal cardiovascular disease.
"This is a wake-up call," said Lewis Kuller
, M.D., Ph.D., at Pitt's Graduate School of Public Health, who heads the WHI site here.
"We need to do a little better. In my 37 years in Pittsburgh, we've made big inroads in reducing air pollution. But it's still a problem."
Readings of fine-particulate pollution at one site near Pittsburgh, in Liberty Borough, regularly exceed federal standards. That site is in an active industrial valley, with plant- and vehicle-produced pollution trapped between hillsides. The recent study used those particulate numbers, submitted by the Allegheny County Health Department to the U.S. Environmental Protection Agency, along with pollution numbers from cities and areas between cities across the nation collected by the EPA.
Each woman's health was compared to the fine-particulate air pollution readings at the nearest monitoring site. The study looked not just at deaths, but also at heart attacks, coronary disease, strokes and clogged arteries. These problems were 24 percent more likely with every 10-unit rise in particles. Almost 3 percent of the women suffered some kind of cardiovascular problem.
Dr. Kuller said the latest study is consistent with previous studies linking particulates to lung and heart disease, but that this was a larger, better done study than done in the past.
The 1,733 women from his site included in the observational study come from a wide area -- some from as far away as Steubenville, Ohio; New Castle and Greensburg. He said the women signed onto WHI in 1984, when they were all in their mid-40s. Still relatively young and healthy at the beginning, their experiences with the onset of cardiovascular conditions was monitored. Dr. Kuller said this is another strength of the pollution study.
"It has a good, biological basis," adding that real physical changes occur in the body with long-term exposure to air pollution: "There are blood and inflammatory markers." He said the most vulnerable are people with asthma and congestive heart failure.
Dr. Kuller said the study adds to the epidemiological, clinical and experimental evidence that low levels of fine-particulate air pollution correlates to higher risk of heart disease.
"The Allegheny County Health Department is very cognizant of this," he said. "It's trying to keep [fine particulate] levels as low as possible. The answer is to be more efficient ... reduce the pollutants from the sources, including pollution that comes here from other parts, west of here."
Guillermo Cole, ACHD spokesman, said the numbers used by the study for the Pittsburgh subjects may not be good, since the Liberty site has among the highest fine-particulate numbers in the country: Out of 12 sites in the county in 2005, the annual average for Liberty was 21.5 micrograms per cubic meter of air. The lowest reading that year was 14.3 at North Park. The annual EPA standard is 15. Recent attempts to lower that number as a standard were unsuccessful.
Mr. Cole said Liberty's three-year average from 2003 to 2005 was 20.8. He said five other sites<