The air you breathe

Along with such well-known risk factors as high blood pressure and elevated levels of cholesterol, air pollution has now been identified as a risk factor for heart disease. Dr. Stephan van Eeden, a Heart and Stroke Foundation researcher, explains.

Q: How does air pollution affect our cardiovascular system?

A: Since the early 1990s, studies at Harvard and around the world have shown that people who live in large polluted cities die of heart attacks and stroke more than they do in smaller, cleaner communities. In all these studies the particles suspended in the air have been implicated in these adverse health effects. The particles are produced predominantly by industry, cars and trucks that burn oil, gas or other fossil fuels. What we have found is that these tiny particles are inhaled and enter deeply into the lungs where they induce inflammation in the lung tissues. This inflammation spills over into the bloodstream and inflame the blood vessels, which allows cholesterol and other substances to easily build up, a condition known as atherosclerosis, one of the main causes of heart attacks and strokes.

 Q: Health Canada reports that air pollution is responsible for about 6,000 premature deaths a year in this country. How many are due to heart disease and stroke?

 A: We estimate that between 60% to 80% of those premature deaths are directly due to cardiovascular disease.    

Q: What can Canadians do to reduce their risk of being exposed to air pollution?

A: Canadians, especially those who already are at risk because of their high blood pressure, diabetes and high cholesterol, or have heart disease, should try to reduce exposure to city smog whenever possible. They should also be physically active away from high traffic areas. So if you jog, do it in a park. If you walk to work, try using quiet side streets instead.

Q: What else can Canadians do about air pollution?

A: Walk, bike, take public transportation or buy a hybrid car – all of these activities will help to lower air pollution in cities. Canadians may also start demanding that their cities be designed to isolate high-traffic thoroughfares away from where people live.