more from WebMD:
The additional risk is slight compared with classic heart attack risk factors like high blood pressure, smoking, or diabetes. But researchers say it’s significant because many people are exposed to air pollution, and heart disease is the leading cause of death in industrialized countries.
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this is the first study to show even short-term exposure to air pollution is enough to increase the near-term risk of heart attack.
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The air pollutants included in the review were ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter.
The results showed all major air pollutants, with the exception of ozone, were associated with a slight increase in heart attack risk.
Researchers say there are several possible explanations for the association between air pollution and heart attack.
For example, previous studies have shown that exposure to air pollution increases inflammation, which is linked to heart attack risk.
In addition, research has shown that exposure to air pollution may increase the heart rate and may make the blood more likely to form potentially dangerous clots.