TTC Air Pollution Levels 10 Times Worse Than Outside Air

Researches compare level to Beijing air quality

A newly published study initiated by Health Canada and co-authored by McGill University and the University of Toronto found that air quality level on the TTC is the worst of all three major transit systems in the country.

The study, published in the Environmental Science & Technology Journal, found that air inside TTC subway stations was 10 times more polluted than the outside air. According to The Star, at levels of 95 micrograms per cubic metre, researchers say that’s approximately the level of air quality in the highly-polluted city of Beijing, China.

Toronto’s subway lines were tested for pollutant levels and compared to Vancouver’s SkyTrain and Montreal’s Metro system. It was found that Toronto’s pollutant levels are three times worse than the Montreal’s Metro.

The study was conducted between 2010 and 2011 by students, who carried backpacks with instruments that measure the fine particulate matter in the air.

Study co-author Greg Evans said “They would travel on the subway and either travel a route continuously, or get out at each station and make measurements there, then wait for the next train.”

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However, lead author Keith Van Ryswyk told The Star the research didn’t measure the effects those measurements had on TTC user’s health. Although, the particulate matter called PM2.5 has been associated with lung problems. Health Canada suggest that PM2.5 levels be kept “as low as possible.”

In an official statement, the TTC stated they are actively involved in the “vitally important role in reducing pollution caused by vehicle emissions.”

“This study was not intended to assess impacts on overall health; rather it looked at levels of certain commonly occurring particulates and pollution. This research was done in 2010 and 2011 at a time we had already started taking steps that will improve air quality on the trains and reduce certain pollutants in the underground stations.”

For more information about the study’s findings, read more at The Star.
Image courtesy C.P.Storm via Flickr