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Study: Smog may trigger heart attacks

July 23, 2010 12:00:00 AM PDT
Experts studying ozone, the major component of smog, have uncovered the first direct evidence that ozone can trigger heart attacks.The U.S. study tracked rats exposed to ozone and rats who breathed filtered air.

According to researchers, the rats exposed to ozone showed a decrease in a heart protective protein, triggering the death of heart cells.

However, researchers caution that more evidence is needed before human studies can begin.