READ THIS NEXT: 3 Ways Your Stomach Is Telling You That Your Heart’s in Trouble. A wide body of research has established a connection between short-term exposure to ambient air pollution and acute coronary syndrome (ACS). This is known to result in hospitalizations and deaths in areas with excessive air pollution. Building on that research, an April 2022 study published in the American Heart Association journal Circulation has learned that inhaling certain air pollutants in particular can increase your heart attack risk “within an hour.” Having analyzed data from nearly 1.3 million ACS patients receiving hospital care in China, the team learned that hourly concentrations of nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO), were all linked with raised heart attack risk. “These associations were strongest in the concurrent hour of exposure,” the study authors noted.ae0fcc31ae342fd3a1346ebb1f342fcb READ THIS NEXT: If Your Legs Feel Like This, Get Your Heart Checked. The researchers pointed out that fine particulate matter (PM2.5) was associated with adverse heart events during the hour of exposure, while coarse particulate matter (PM2.5-10) was not. “Particulate matter contains microscopic solids or liquid droplets that are so small that they can be inhaled and cause serious health problems,” explains the Environmental Protection Agency (EPA). “Some particles less than 10 micrometers in diameter can get deep into your lungs and some may even get into your bloodstream.” A separate EPA report confirms that “long-term exposure to fine particulate matter, known as PM2.5, can impact heart disease.” The EPA warns that depending where you live, you may come into contact with air pollutants that “adversely affect the heart” on a regular basis. “Air pollution particles are emitted year round from motor vehicles, power plants, industries, and forest fires and are created when sunlight interacts with vapor and gaseous pollutants,” the environmental authority explains. The Circulation study says that exposure to such pollutants “may trigger the onset of ACS, even at concentrations below the World Health Organization air-quality guidelines,” a fact that the study authors described as a “surprise.” Haidong Kan, PhD., a professor in the School of Public Health at Fudan University in Shanghai and a lead author of the study, explained: “Any concentrations of air pollutants (such as fine particulate matter, nitrogen dioxide, sulfur dioxide and carbon monoxide) recorded in the present study may have the potential to trigger the onset of a heart attack.” However, experts from the American Heart Association also noted that “as levels of the studied pollutants rose, so did the risk for heart attacks.” While anyone can experience the adverse effects associated with air pollution, the researchers behind the study noted that some people may be at an outsized risk of acute heart events. “Greater magnitude of associations was observed among patients older than 65, without a history of [tobacco use] or chronic cardiorespiratory diseases, and in the cold season,” they wrote. Especially if you are in a high-risk group, it’s essential to try to limit your exposure to air pollutants when possible. Wearing a face mask in places with clear evidence of air pollution—or avoiding those areas entirely—can help mitigate your risk. READ THIS NEXT: Not Doing This Before Bed Could Be Hurting Your Heart, Experts Warn.