CNN —
The number of people killed or disabled from certain heart diseases caused by exposure to air pollution has increased significantly since 1990, to 31 percent worldwide, according to a study published Wednesday in the Journal of the American Heart Association.
Researchers say particulate pollution is particularly to blame. Also known as PM2.5 or particulate matter pollution, this pollution is a mixture of solid and liquid droplets suspended in the air. It can come in the form of dirt, dust, soot, and smoke, according to the U.S. Environmental Protection Agency. Particulate pollution comes from coal-fired and natural gas-fired power plants. Vehicles, agriculture, unpaved roads, construction sites, and wildfires can also cause this pollution.
Particle pollution is particularly dangerous: PM2.5 particles are invisible because they are 1/20th the width of a human hair, and they travel past the body’s normal defences. Instead of being expelled when you exhale, they can get stuck in the lungs or enter the bloodstream.
Particles can cause irritation and inflammation, which can lead to respiratory diseases. Studies have shown that long-term exposure to particle pollution can cause cancer, dementia, depression, respiratory diseases and various heart diseases.
In the new study, researchers analyzed nearly 30 years of mortality and disability data from a set of studies called the Global Burden of Disease 2019, which provides population estimates for 204 countries and includes information on mortality and disability from exposure to particulate matter pollution.
The data tracked two heart-related problems: stroke and ischemic heart disease, a condition in which the heart doesn’t get enough blood and oxygen primarily due to a buildup of plaque in the arteries.
The researchers found that the combined number of premature deaths and years of heart disease-related disability that could be attributed to exposure to particulate pollution increased from 2.6 million in 1990 to 3.5 million in 2019. Premature deaths alone fell 36.7% over that period, but it wasn’t all good news.
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“The decline in deaths may be considered good news as it indicates improved access to healthcare, air pollution control measures and treatment. However, the increase in disability-adjusted life years suggests that while fewer people are dying from cardiovascular disease, more people are living with disability,” said Dr. Farshad Farzadfar, a professor of medicine at the Center for Noncommunicable Disease Research, Institute of Endocrinology and Metabolism, Tehran University of Medical Sciences in Iran and co-author of the study.
The study found that men are much more likely to die from exposure to particulate pollution than women, and wealthy countries lost the fewest years of life due to this pollution, but also the most people living with heart-related problems.
Experts say pollution-related heart disease will likely continue to rise as global temperatures rise, and previous studies have found that heatwaves and days with high pollution levels can double the risk of a fatal heart attack.
Although many countries have enacted laws and incentives to reduce air pollution, nearly the entire world population breathes air that exceeds World Health Organization air quality standards, and the number of days with “very unhealthy” and “hazardous” air quality is increasing every year, largely due to the climate crisis. In 2011 alone, a study found that exposure to this type of pollution was responsible for 107,000 premature deaths in the United States alone, not just from heart disease but from all causes.