TT traffic pollution comparable to busiest highway in N America

Traffic-related air pollution near major roadways in TT is so intense that it is comparable to highways in places like Toronto and Detroit.

The study, by Trinidadian-born University of Toronto student Kerolyn Shairsingh, found that levels of black carbon around industrial areas on the islands were elevated to levels comparable to Ontario Highway 401, North America’s busiest highway. Levels near major roads in Trinidad were significantly higher.

This is the first study of local emissions done in TT, a release from the Canadian university said.

Shairsingh is a doctoral candidate in chemical engineering. The findings of her study were published recently in the Journal of Science and the Total Environment.

The study focused on black carbon content, also known as soot, which is released from gasoline and diesel engine exhaust and has been linked to negative health outcomes, including lung conditions and cancer.

Shairsingh, in a release, said she was motivated to research local concentrations of black carbon after years of experiencing asthma attacks every time she travelled home.

“I have nephews who also have asthma. Sometimes they can’t go outside and play because they would be wheezing,” said Shairsingh. “I always knew that the air quality was poor, but nobody monitors any air quality here at all.”

When she visited home in February 2018, she decided to take air-quality monitoring equipment with her. Shairsingh set up ten monitoring sites across TT over a three-week period, including some near oil and gas refineries, urban residences, and major roads, including highways and bus routes.

“What shocked me is that it’s actually traffic that is more of the culprit than the industries here, at least for this particular pollutant,” says Shairsingh.

One site, a commercial area in Trinidad with frequent sidewalk traffic, showed black-carbon levels 1.1-times higher than Health Canada’s proposed limit for long-term black-carbon exposure. Long-term exposure to black carbon has been shown to pose health risks such as asthma, respiratory infections, lung cancer, strokes and cardiovascular mortality.

Shairsingh said the major source of black carbon is diesel exhaust. At half the price of gasoline, diesel fuel is prevalent in many of the half-million vehicles driven daily in TT.

Although the country passed air-pollution legislation in 2014, Shairsingh said the guidelines were mostly geared towards industry.

“There’s nothing for the monitoring of vehicles at all,” she says.

Shairsingh hopes this study of local emissions will be the first step towards improving the air quality, either through cleaner fuel sources or through retrofitting large vehicles such as buses and trucks.

She is also working on a documentary, Clearing the Air, to further spread awareness of the issue among the residents of TT and beyond.