Study shows heat and smog are killers

Smog is responsible for more than 800 deaths a year in Toronto, and extreme heat makes the problem even worse, a new government study has found.

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The issue appears to be just as bad, in relative terms, in three smaller cities – Montreal, Ottawa and Windsor, Ont. – that were studied by a team of scientists from Toronto's public health department, the federal government and McMaster University in Hamilton.

Data from the study were released in Toronto on Monday, which happened also to be the first day this year that that city announced a heat alert, advising residents to:

• Keep cool.
• Take rests.
• Drink lots of water, whether they are thirsty or not.
• Check on elderly or frail neighbours, relatives and friends who live alone.
• Take advantage of air conditioning in public places such as malls, community centres and libraries.

Monday was also the 14th day this year that Ontario's environment department issued a smog alert for Toronto. That matches the total number of smog warnings that were issued in all of 2004 – and this year's summer has not yet officially started.

The study measured the impact of extreme cold, extreme heat and air pollution on premature deaths in the four cities over a 46-year period.

It concluded that extreme heat was killing an average of 120 people a year in Toronto, 121 in Montreal, 41 in Ottawa and 37 in Windsor.

Extreme cold was responsible for an average of 105 deaths a year in Toronto, 143 in Montreal, 54 in Ottawa and 32 in Windsor.

The air pollution that causes smog was found to be the cause of 822 deaths a year in Toronto, 818 in Montreal, 368 in Ottawa and 258 in Windsor.

The study predicted that heat-related deaths will double by 2050 and triple by 2080 because of global warming.

Increased air pollution will cause a 20 per cent increase in smog-related deaths by 2050 and a 25 per cent increase by 2080, the study estimated.

The scientists recommended the federal government introduce a national heat warning system such as Toronto's.

And they urged the federal government to focus on mandatory, rather than voluntary measures to meet Canada's targets under the Kyoto Protocol for reducing smog and greenhouse gases.

• INDEPTH: Kyoto Protocol