Long Term Exposure to Particulate Matter Associated With Increased Risk of Heart Attack

A European research team claims that long term exposure to particulate matter leads to an increased risk of heart attack.

The population based study conducted by scientists at Helmholtz Zentrum Munchen, uncovers the correlation between exposure to particulate air pollution and heart diseases. The researchers say that the association is very much apparent at particulate levels below the prescribed  European limit values (EU).

In order to investigate the effects of air pollution on health, the researchers looked at eleven population groups in Finland, Sweden, Denmark, Italy and Germany. The researchers identified that the high concentration of the particulate matter at the residence location elevates the risk of acute coronary event. The researchers evaluated data of more than 100,000 subjects.

None of the participants had a history of any cardiovascular disease at the start of the study. They were followed for the occurrence of a coronary events for an average of 11.5 years.

The atmospheric particulate matter(PM) are tiny particles and liquid droplets that contain acids, dust particles, metals or organic chemicals. They are suspended in the air as atmospheric aerosols and are known to have adverse effects on human health. They also have an impact on climate and precipitation. The naturally occurring particulates originate from volcanoes, forests, grassland fires etc. Exposure to particulate matter is the 13^th leading cause of death worldwide, according to the World Health Organization as it contributes to nearly 800,000 premature deaths each year.

In the current study, it was seen that a total of 5,157 people suffered a heart attack or unstable angina pectorsis in the follow-up years. These two are caused by the hardening of the coronary vessels. It was also seen that rise in 5 µg/m³ of annual concentration of PM2.5 or 10 µg/m³ of PM10 in the air led to a 13 and 12 percent increased risk of heart attack.

The risk was high even when the concentration level was below the present EU guidelines of 25 µg/m³ for PM2.5 and 40 µg/m³ for PM10.

"Our results show that exposure to particulate matter poses a significant health risk - and an even greater risk than previously thought," said Professor Annette Peters, lead author of the study. "The adverse health effects that occurred at exposure levels below the current specified limits are particularly alarming. The study therefore supports the demands to lower these limits." 

This study is documented in the British Medical Journal.