An estimated 700,000 Canadians will die prematurely over the next two decades because of illnesses caused by poor air quality, the Canadian Medical Association said in a report Wednesday.

This year, an estimated 21,000 Canadians will die from heart and lung illnesses brought on by breathing polluted air, the CMA said. Most of the deaths will be among people over 65, who are most vulnerable to heart disease.

The study predicts that 18,000 people will be admitted to hospital suffering from the effects of air pollution in 2031, up from 11,000 this year.

In the long term, air pollution leads to higher rates of cardiovascular disease by damaging muscle cells in the arteries of the heart, causing them to harden. In the short term, air pollution affects how blood clots leading to more heart attacks during bad air days, said Dr. Ted Boadway, the group's technical adviser on health and environment.

The costs of dirty air, in terms of treating the illnesses in hospital and visits to doctors, as well as indirect expenses for time off work, will add up to $10 billion this year.

The costs will rise to $250 billion by the year 2031 if no improvements are made, said Dr. Brian Day, CMA president.

"This is the time of the Olympics, and we're talking about air quality in China," said Day, an orthopedic surgeon based in Vancouver. "It's all well and good to criticize other countries, but let's get our own house in order."

Most of the premature deaths are expected to occur in Ontario and Quebec, home to 62 per cent of the country's population. Pollution drifting north from the U.S. Midwest, as well as from this country's manufacturing industries, are to blame. People living in cities and rural areas of central Canada suffer the health effects, Boadway told reporters.

"Approximately 70 per cent of acute premature deaths will come from these two provinces, possibly reflecting their poorer air quality relative to other parts of Canada," said the report, titled No Breathing Room: National Illness Costs of Air Pollution.

"Western Canada, with approximately 30 per cent of the population of Canada, accounts for one quarter of the acute premature deaths."

No province is performing well in terms of environmental illness from air pollution, said Day, noting the report's estimates assumed air pollution will not rise above current levels.

While the CMA does not make policy, Day urged governments to respond to the health effects of the environment, or pay the price at the polls, since everyone has to breathe.

A U.S. review released Wednesday also highlights how air pollution is linked to cardiovascular disease.

"Air pollution can be dangerous at levels that are within the accepted air quality standards," said author Dr. Boris Simkhovich, a researcher at the Heart Institute of the Good Samaritan Hospital in Los Angeles.

The American College of Cardiology, which published the review in the Aug. 26 issue of its journal, said the link offers "another compelling reason to campaign for improved air quality."