Pollution May Trigger Heart Attacks
June 11 -- A study released in the journal Circulation by National Research Center for Environment and Health researchers says small air pollutants can trigger a heart attack within two hours of inhalation.
Microscopic particles spew from cars and refineries and power plants every day. Mounting evidence suggests that breathing these particles can be life threatening.
In the latest study, researchers found that the more particles in the air, the greater the risk of having a heart attack — up to a 48 percent greater risk. Those most affected are older people with chronic heart or lung disease.
The study was done in Boston, a city with relatively clean air. Researchers say the heart attack risk might be even greater in more polluted cities, such as Houston, Los Angeles or New York.
And the study suggests the damage may occur quickly.
"What we found was a very short-term effect," says Dr. Murray Mittleman, a specialist in cardiovascular disease at the Beth Israel Deaconess Medical Center and a professor at the Harvard School of Public Health. "Within about two hours of breathing in these very fine particles, the risk of heart attack was elevated."
Researchers say the problem begins when the particles penetrate deep into the lungs and cause inflammation. That triggers the lungs to release certain chemicals, which pass into the bloodstream and onto the heart, disrupting the heart's rhythm.
Scientists now measure the effects of the heart, beat by beat.
"These effects could be manifested by an increased heart rate, a lowered heart rate variability or evidence that the heart is not receiving enough oxygen," explains Henry Gong, Jr., professor at the Keck School of Medicine at the University of Southern California.
These effects may explain why more people suffer heart attacks on those hot, hazy, pollution-filled days of summer.
Related Stories
ABC News Live