EPA researchers and partners are learning more about how people can better protect their cardiovascular health from air pollution.
A large body of research has been published in peer-reviewed journal articles by EPA and EPA-funded scientists on the health effects of air pollution, including the heart, nervous and vascular systems.
A significant body of research has shown that long-term exposure to fine particle pollution, known as PM2.5, can impact heart disease. Particles are emitted year-round from motor vehicles, power plants, industries, and naturally from forest fires. PM also develops from chemical reactions in sunlight from vapor and gaseous pollutants.
Scientists continue to study the association between air pollutants and pollutant mixtures and cardiovascular system and stroke. A sample of published research is listed below.
- Exposure to course particle pollution causes metabolic changes
Short-term exposure to rural coarse particulate matter leads to an increase in endothelial progenitor cell (EPC) levels, which is an indication of metabolic changes, according to an EPA-funded study. The rising levels of EPC can contribute to the risk of cardiovascular disease and diabetes.
The effect of acute exposure to coarse particulate matter air pollution in a rural location on circulating endothelial progenitor cells: results from a randomized controlled study, published in Inhalation Toxicology in August 2013.
- Link found between air pollution and susceptibility to metabolic syndrome
Scientists found that short-term exposures to concentrated air pollutants and ozone in obese rodents resulted in inflammation and oxidative stress in the fat around the heart and kidney. Rodents on a high-fructose diet had a greater response. The findings may provide a link between air pollution exposure and accelerated susceptibility to metabolic syndrome, a group of risk factors that increases your risk for heart disease and other health problems such as diabetes and stroke. The research was funded by EPA’s STAR program.
Ambient fine particulate matter and ozone exposures induce inflammation in epicardial and perirenal adipose tissues in rats fed a high fructose diet (PDF), (2 pp, 34K) published in Particle and Fibre Toxicology in 2013.
- Diesel exhaust can impact “good” cholesterol
Exposure to diesel emissions can change the function of high density lipoproteins (HDL) from good to bad. HDL is normally seen as the “good” cholesterol that helps moderate the bad effects of low density lipoproteins (LDL). The development of dysfunctional HDL resulting from exposure to diesel exhaust emissions could be a pathway by which air pollution leads to enhanced atherosclerosis and heart problems, according to the study funded by EPA’s STAR program.
Diesel exhaust induces systemic lipid peroxidation and development of dysfunctional pro-oxidant and pro-inflammatory high-density lipoprotein, published in Arteriosclerosis, thrombosis, and vascular biology on April 4, 2013.
- Can controlling high blood pressure protect against air pollution?
A study shows that when medication is used to reduce blood pressure in rodents who are genetically predisposed to hypertension, there is an extra benefit. Controlling blood pressure also reduced some of the negative health impacts of long-term exposure to diesel exhaust on the pulmonary and cardiovascular systems.
The research is making an important contribution to understanding how to improve public health since the World Health Organization estimates more than 30 percent of adults worldwide have high blood pressure. The paper was featured online by World Biomedical Frontiers, an organization that focuses on cutting-edge biomedical research from around the globe.
Diesel exhaust induced pulmonary and cardiovascular impairment: The role of hypertension intervention, published in Toxicology and Applied Pharmacology on April 15, 2013.
- Nitrogen dioxide may enhance cardiac effects of fine particulate pollution
Recent epidemiology studies associated nitrogen dioxide (NO2) exposure with cardiovascular effects and suggest that the gas is merely a marker of traffic-related air pollution. A study by EPA and Duke University Medical Center scientists examined effects of a mixture of NO2 and fine particles (PM2.5). The study suggests NO2 exposure may produce and enhance acute cardiovascular effects of fine particulate matter exposure.
Synergistic effects of exposure to concentrated ambient fine pollution particles and nitrogen dioxide in humans., published in Inhalation Toxicology on Oct. 24, 2012.
- Ozone may impact cardiovascular system
A clinical study by EPA found that ozone caused temporary changes in the cardiovascular system. The ozone exposure caused inflammation of the vascular system and resulted in a change in heart rate variability and a reduction in the ability of blood clots to dissolve, which are two risk factors for heart disease. This study shows ozone has the potential to impact the cardiovascular system.
Controlled Exposure of Healthy Young Volunteers to Ozone Causes Cardiovascular Effects, published in the American Heart Association’s journal, Circulation, on June 25, 2012.
- Higher health risk found for heart patients living near major highways
EPA’s Clean Air Research Center at Beth Israel Deaconess Medical Center has found that heart attack survivors face air pollution health risks associated with living near major highways. Over a study period of 10 years, heart attack survivors living less than 100 meters or 328 feet from a roadway were found to have a 27 percent higher health risk compared to survivors living at least 1,000 meters or 3,277 feet away. That risk lowered to 13 percent for those living between 200 and 1,000 meters or 656 to 3,277 feet from the roadway.
Residential Proximity to Major Roadway and 10-Year All-Cause Mortality After Myocardial Infarction, published in the American Heart Association’s journal, Circulation, on May 7, 2012.
- Fish oil may help heart patients
In a study, EPA scientists found evidence that omega-3 fatty acids (the kind found in most fish oil supplements) may protect the cardiovascular system from the harmful effects of fine particle pollution. The study found that 3 grams of fish oil daily helped to prevent symptoms such as a change in heart rate variability and heart rhythm that could contribute to heart problems in people with heart disease. Always check with your personal doctor before starting a dietary supplement such as fish oil.
Omega-3 Fatty Acid Supplementation Appears to Attenuate Particulate Air Pollution Induced Cardiac Effects and Lipid Changes in Healthy Middle-Aged Adults, published in Environmental Health Perspectives on April 19, 2012.
- Cardiac effects found with ozone exposure
EPA scientists found that exposure to varying levels of ozone has both direct and indirect effects on the heart. Rats exposed to 0.8 parts per million (ppm) of ozone experienced immediate and clear changes in heart function including heart arrhythmias and abnormal electrocardiograms (ECG). While there were no direct changes in heart function when the rats were exposed to 0.2 ppm of ozone, they were more likely to have alterations in heart function when the heart was stressed 24 hours after exposure.
Overt and latent cardiac effects of ozone inhalation in rats: evidence for autonomic modulation and increased myocardial vulnerability, published in Environmental Health Perspectives on Dec. 2, 2011.