Heart Disease and Air Pollution

How particle pollution affects the heart

The EPA says particles smaller than 10 micrometers can get deep into the lungs, some may even get into the bloodstream, and exposure can affect both the lungs and the heart. The studies it cites link particle pollution to premature death in people with heart or lung disease, nonfatal heart attacks and irregular heartbeat.^[2]

AirNow adds that when people with heart or lung disease and older adults are exposed to these small particles, they are more at risk of hospital and emergency room visits or, in some cases, death from heart or lung disease.^[4]

The American Lung Association separates short-term from long-term exposure. Short-term exposures of hours to days can trigger cardiovascular events, hospitalizations and deaths. Long-term exposure over months to years can increase the risk of strokes and coronary heart disease and cause premature deaths.^[5] The National Institute of Environmental Health Sciences (NIH) notes research showing fine particles can impair blood vessel function and speed up calcification in arteries.^[7]

Why you can't rely on symptoms alone

This is the most important point in the EPA's guidance. For people with heart disease, the EPA says exposure to high particle levels can cause serious problems in a short time, even heart attacks, with no warning signs. People with heart disease shouldn't assume they are safe just because they feel fine.^[3]

The EPA lists symptoms such as chest pain or tightness, palpitations, shortness of breath, or unusual fatigue as possible signs of a serious problem.^[3] If you have them, follow the plan your doctor gave you, and get emergency care for chest pain.

Who is most at risk

The EPA's particle pollution sensitive groups are people with heart or lung disease, older adults, children, people with diabetes and people of lower socioeconomic status.^[3] The American Lung Association adds that older adults are more likely to have chronic illnesses such as heart and lung disease, which exposure to unhealthy air can make worse.^[6]

What to do when the AQI is orange or higher

• Cut back on exertion. At a particle AQI of 101–150 (Code Orange), the EPA advises people with heart disease and the other sensitive groups to reduce prolonged or heavy exertion.^[3]
• Plan routes away from traffic. The EPA says walkers, runners and cyclists can reduce exposure by avoiding busy roads, and drivers can set ventilation to "recirculate" on busy roads.^[3]
• Clean the air indoors. The EPA recommends choosing a portable air cleaner with a CADR big enough for the room. It reports that studies with portable HEPA air cleaners found small improvements in cardiovascular and respiratory health, typically measurable rather than noticeable.^[8] Avoid air cleaners that intentionally produce ozone.^[8]
• Check before you go out. Use the city air quality pages or the outdoor time calculator to plan around high readings.

Ask your cardiologist or primary care doctor how air quality should fit into your own care plan.

What the AQI colors mean

AirNow reports the Air Quality Index (AQI) for five pollutants regulated under the Clean Air Act: ground-level ozone, particle pollution (PM2.5 and PM10), carbon monoxide, sulfur dioxide and nitrogen dioxide.^[1]

• Green, 0–50 (Good): air pollution poses little or no risk.^[1]
• Yellow, 51–100 (Moderate): acceptable, but there may be a risk for people who are unusually sensitive to air pollution.^[1]
• Orange, 101–150 (Unhealthy for Sensitive Groups): members of sensitive groups may experience health effects; the general public is less likely to be affected.^[1]
• Red, 151–200 (Unhealthy) and above: some members of the general public may experience health effects, and sensitive groups may experience more serious effects.^[1]

Check today's reading for your area on the city air quality pages or at AirNow.gov.