Instinctively we know that exposure to high levels of air pollution can harm a person’s respiratory system. But there is research that air pollution increases cardiovascular problems and mortality. The World Health Organization estimates that air pollution is the major cause of 24% of deaths from coronary heart disease and 25% of fatalities due to strokes.1
The Environmental Defense Fund lists air pollution as the environmental danger that is most responsible for premature deaths.2 Read on to learn how air pollution impacts heart health and what can be done to manage exposure to dangerous air pollutants.
How air pollution affects heart health
When inhaled, many of the particles in polluted air are so tiny they can eventually reach the circulatory system, including the heart. Their impact includes a higher risk of irregular heartbeat, or arrhythmia, heart attacks, and stroke. This is especially true with long-term exposure, but damage to the heart can happen even over the short-term.3
Research has shown that once pollutants move into the circulatory system they can cause inflammation, damage blood vessels and increase arterial calcification – all of which help account for the increased potential for cardiovascular complications.4,5
Dangers of specific pollutants
Fine particulate matter, or PM2.5, and ultrafine particles infiltrate deeper into the lungs than other pollutants, which make them one the greatest dangers to heart health.6 PM2.5 are particles that are 2.5 microns or smaller in diameter, while ultrafine particles measure less than 0.1 microns in diameter.
The combustion of fossil fuels leads to the creation of volatile organic compounds and nitrogen oxides such as nitrogen dioxide, and once they react with each other, ozone is formed. Even short-term exposure has been known to cause chest pain. Long-term exposure has been blamed for chronic obstructive pulmonary disease (COPD).
When fossil fuels that contain sulfur are burned, sulfur dioxide (SO2) is released as a byproduct. SO2 has been identified as having a damaging impact on the cardiovascular system.
Another air pollutant that adds to an increased risk of heart disease is black carbon. Sources of black carbon emissions include:
- combustion engines (especially diesel)
- fireplaces and wood stoves
- coal and heavy oil heating systems
- waste burning
Some are more vulnerable to air pollutants
Studies have indicated that there are several groups more endangered by the harmful effects of air pollution. These groups include:
- pregnant women
- older adults
- people with pre-existing heart or lung disease
- those living in areas with elevated levels of pollutants in the air
A report from the National Toxicology Program detailed how exposure to transportation-related air pollution (TRAP) during pregnancy heightens the threat of severe changes in blood pressure, also called hypertensive disorders. Besides being known sources of pre-term births and low birth weight, these disorders are also linked to the deaths of pregnant women and their unborn children.7
Post-menopausal women were found to be at a higher risk of stroke if they were exposed daily, even in the short-term, to nitrogen oxides.8
A group of men and women 45- to 84-years-old were part of a study looking for a connection between air pollution and the levels of HDL cholesterol, also known as the good cholesterol, in their bodies. It was discovered that those in the group that experienced greater exposure to traffic-related pollution had lower levels of HDL cholesterol, which increases the risk of heart disease.9
The National Heart, Lung and Blood Institute is working with the U.S. Environmental Protection Agency (EPA), the Centers for Disease Control and Prevention (CDC) and other organizations to help improve communication to the public about these health concerns with the goal of lowering communal exposure to air pollution.
To protect your health from the damaging, sometimes fatal effects of pollutants in the air: