What we put into the air, we put into our lungs!

Article by: Dean Spence

About 30 per cent of the world’s carbon dioxide production comes from Canada and the U.S.A.  One quarter of this is associated with transportation–mostly single-passenger automobiles.

David Suzuki, Ph.D in Zoology, often notes the absurdity of transporting a ninety kilogram person in 2 tonnes of metal.  This is not sustainable, especially in urban areas where public transit is readily available.

Worldwide, the demand for cars is only increasing, especially in countries like China and India. Consider Delhi, where the air often contains six to 10 times the internationally accepted level of harmful fine particulate matter (PM2.5).  One major culprit of this is vehicles.  Every day, Delhi adds 1500 cars to its roads.  The Indian government recently announced plans requiring that odd and even license plate would alternate daily on the roads in Delhi for two weeks.

U of T professor Greg Evans, Ph.D, P.Eng., and his team study the sources, chemical transformation and health impacts of air pollutants.  Recently they have focused on traffic-related air pollution (TRAP) in large cities like Toronto.  According to Evans, TRAP is a key source of air pollution in Canadian cities which affects the health of 1 in 3 Canadians living near major roads.

“We are studying the pollutants in individual exhaust plumes as vehicles drive by our lab on College street,” Evans said via email.  “We have measured the exhaust of over 100,000 vehicles and found that a small portion of the vehicles are emitting a large portion of the pollution.  This represents a great opportunity to improve air quality, removing this small number of vehicles from the road, or cleaning up their emissions could produce a dramatic reduction in air pollution.”

Automobile technology has improved significantly in recent years, largely in response to stricter fuel-emission standards in countries such as Canada and the U.S.A.  However, as Suzuki points out in Everything Under the Sun, hybrid cars still use fossil fuels and electric car technology does not solve all of the issues because electricity often comes from coal-fired power plants.   Evans says there is often a trade-off with new vehicle technologies.

“We have been studying emissions from vehicles equipped with the new gasoline direct injection (GDI) engines.   These cars will soon be the dominant types sold in Canada.  These GDI equipped cars are more fuel efficient which is good news in terms of climate change.  However, after taking measurements in our vehicle emissions lab we have discovered they also emit more of a number of pollutants potentially increasing the burden on health.”

Evans and his team also investigate how aerosols impact human health and the environment.   He describes aerosol particles as either microscopic liquid or solid particles which are suspended in the air.  Aerosols can be created by such natural sources as oceans, deserts, forest fires and volcanoes.  They can also be created by such anthropogenic sources as vehicles, industrial processes, coal-based electricity generation, or even candles or cooking at home.

“They are a complicated soup of chemicals and can travel deep into our lungs,” Evans said. “The smallest ultra fine particles can even travel in blood cells to different parts in our bodies.  Every time we breathe we inhale millions of these particles, depending on how polluted the air is.  This can have substantial impacts on health.  Air pollution is the number one environmental burden on health, associated with over three million deaths a year globally.  Much if this burden is due to these aerosol particles.”

Much of the research that Evans and his team conduct is executed through The Southern Ontario Centre for Atmospheric Aerosol Research (SOCAAR).  As director of SOCAAR Evans heads the interdisciplinary centre that brings together medical personnel, atmospheric chemists and environmental engineers in collaborative, state-of-the-art facilities and in partnership with government and industry.

“SOCAAR’s main goal is to produce a broad, trans-disciplinary and actionable understanding of the origins, characteristics, environmental impact, and health consequences of atmospheric aerosols.  SOCAAR is also part of the Canadian Aerosol Research Network, along with sister centres in Dalhousie University and and the University of British Columbia.”

Evans’ research is not just limited to what he and his team investigate out of their College street lab.  They also have a mobile research facility that allows them to study air quality throughout Ontario.

MAPLE (Mobile Analysis of ParticuLate in the Environment) allows us to get out of the lab and investigate air quality at sites around Ontario.  Recently we have been using MAPLE to measure air quality across the GTHA through sampling.  We have also measured emissions from vehicles on the highway as we drive near them on the highway.”