Air pollution puts people's hearts at risk, report says

BY LAUREL MYERS

Diet and lifestyle aside, people now also need to worry about the air they're breathing and the impact it has on their hearts, according to a report released Monday by the Heart and Stroke Foundation.

The 2008 Report Card on Canadian's health revealed air pollution is now a year-round threat to the heart health of Canadians. However, only three percent of those surveyed recognized the problem, while seven out of ten Canadians thought air pollution tends to be worse in the summer.

And although Canadians seem to make the connection between pollution and some major diseases, heart disease is highly under-recognized, the report said.

"If you do have an underlying heart condition, diabetes or are elderly, you're risk of heart attack or stroke is increased by 76 percent on poor air quality days," said Stephen Samis, director of health policy at the Heart and Stroke Foundation of Canada.

"(However), evidence shows that even people without an underlying heart condition, every 10 unit increase of fine particulate matter can increase your risk or a heart attack by up to 69 percent."

Fine particulate matter refers to tiny particles or droplets in the air that are two and a half microns or less in diameter, and come from a variety of sources including factories, motor vehicles, windblown dust and wood stoves or backyard burning. Samis explained fine particulate matter was isolated in the report card because it has been shown to be the worst type of pollution for heart health.

However, in comparison to other established risk factors of heart health, the risk factor of air pollution is still lower on the spectrum.

"The most important risk factors for cardiovascular disease continue to be poor diet, lack of physical activity and smoking," the director said. "Also, the science around air pollution and cardiovascular disease is still unfolding whereas the science around something like smoking is very well established.

"You're much more likely to have a heart attack or stroke because you smoke than because of air pollution."

According to the report, while 63 percent of those surveyed believe air quality has a major effect on health, 61 percent don't let smog advisories affect what they do outdoors.

"We encourage Canadians who don't have a heart condition, diabetes or are elderly to be physically active, even outdoors and even on bad air days," Samis said. "You're still better off going outside than not. But If you are going to go outside for a run or walk, do so away from vehicles and other sources of pollution."

In Sudbury in particular, Samis said the peak level of fine particulate matter pollution measured in the air is just below the Canadian standard of 30, a better score than a number of communities across the province.

"Sudbury was once known for the pollution that came from the Inco smelter," he said, adding this ranking points to another area the Heart and Stroke Foundation was trying to get across in  their report card.

"Because the smokestack in Sudbury is built so high, the wind carries a lot of the pollution away from the city," he said.

"That type of pollution can travel up to 800 kilometers. Whichever way the winds are blowing, that's where the pollution goes."

The highest reading in Ontario came from Burlington with a reading just below 50.

During the winter, the issue of fine particulate matter pollution becomes an issue as many Northerners rely on wood stoves and fireplaces for their source of heat, which is also a source of dangerous air pollution. Wood-burning stoves and fireplaces are responsible for 28 percent of fine particulate matter pollution in Canada, a statistic that was shocking to the researchers at the Heart and Stroke Foundation, Samis said.

The survey reports 44 percent of Canadians living in communities of less than 10,000 use wood heat through the winter, 70 percent of those on a daily or almost daily basis.

"If Canadians choose wood-heating as their heat source, they should choose a stove that is approved by the Canadian Standards Association or by the Environmental Protection Agency," Samis said. "They are built according to performance standards that aim at limiting harmful emissions."

All in all, though Samis admitted people should be concerned with what they're breathing in, the other risk factors of cardiovascular disease trump air pollution.

"While it's still a risk factor, it's far more important to quit smoking or to take a walk."