Coming up for air

It took a concerned daughter of TT to put hard facts to something that most citizens are at least dimly aware of, the deteriorating quality of air in city centres and on highways.

Congested traffic jams and an absence of vehicle emissions control beyond visual inspection of automobiles for obviously bad exhaust have created concentrations of pollution on major roads according to a study by Trinidad-born University of Toronto (UT) student Kerolyn Shairsingh. Shairsingh undertook a three-week study in February 2018 during a visit home, bringing along air quality monitoring equipment to evaluate the levels of pollution near oil and gas refineries, urban residences and major roads. What she found was startling, but given local legislation, ultimately unsurprising. Air pollution laws passed in 2014 set limits for industry, where Shairsingh’s devices found less pollution compared to the levels found in high traffic areas.

The study focussed particularly on concentrations of black carbon and particulate matter in the ambient air at all ten locations. At one commercial site with frequent pedestrian traffic, her devices registered black carbon exposure levels 1.1 times higher than the limit for black carbon exposure set by Canada’s health regulators. Diesel may be a cheap fuel locally, but it’s a prime producer of black carbon, or soot, which can increase health risks for asthma, respiratory infection, lung cancer, strokes and cardiovascular mortality.

Shairsingh, who is a PhD candidate in UT’s Department of Chemical Engineering and Applied Chemistry under the supervision of Professor Greg Evans, found black carbon levels five times higher in Trinidad than in Tobago, higher concentrations during rush hour and spikes in concentrations near roadways serviced by diesel buses.

The research has been hampered by a lack of information in the subject area. There is no regulation of levels of particulate matter in TT, Shairsingh found, so there is no monitoring or records of levels nationwide for comparison, but her research suggests that these pollution levels are the result of trans-boundary pollution, particulate matter that’s common to this part of the Caribbean transported by airmasses originating in the Sahara Desert, North America and the Atlantic Ocean. This study plants an important flag for data collection on subject matter that should be of concern to all citizens, pointing as it does to other areas of concern beyond Sahara dust as an issue for respiratory health.

With two universities based locally, it’s also a beacon of challenge to TT science students to develop more studies that build an overdue corpus of peer-reviewed scientific data with enough integrity to offer national policy planners a fact-based point of reference to guide strategic decisions on environmental matters which affect everyone.