Air pollution studies that ignore the effects of noise may overestimate the health effects of emissions
27 October 2018
Air pollution and transportation noise are both associated with an increased risk of heart attacks. Studies on air pollution that do not take into account traffic noise tend to overestimate the long-term effect of air pollution on heart attacks, concluded a study by the Swiss Tropical and Public Health Institute published in the European Heart Journal.
Where air pollution is high, the level of transportation noise is usually also elevated. Not only air pollution negatively impacts health, but also car, train and aircraft noise increases the risk for cardiovascular diseases and diabetes, as previous research has demonstrated.
The study looked at the combined effects of air pollution and transportation noise for heart attack mortality, by considering all deaths that occurred in Switzerland between 2000 and 2008. Analyses that only included fine particulates (PM2.5) suggest that the risk for a heart attack rises by 5.2% per 10 µg/m3 increase in the long-term concentration at home.
Studies that also account for road, railway and aircraft noise reveal that the risk for a heart attack attributable to fine particulates in fact increases considerably less; 1.9% per 10 µg/m3 increase. These findings indicate that the negative effects of air pollution may have been overestimated in studies which fail to concurrently consider noise exposure.
“Our study showed that transportation noise increases the risk for a heart attack by 2.0 to 3.4% per 10 decibels increase in the average sound pressure level at home,” said Martin Röösli, Head of the Environmental Exposures and Health Unit at Swiss TPH, and lead author of the published research. “Strikingly, the effects of noise were independent from air pollution exposure.”
The study also found that people exposed to both air pollution and noise are at highest risk of heart attack. Hence, the effects of air pollution and noise are additive.
Source: Swiss TPH