A new study by The Southern Ontario Centre for Atmospheric Aerosol Research at the University of Toronto has found that in some instances, GO train passengers are at risk of being exposed to diesel exhaust.

The results were first shared with the Toronto Star, who reported that anyone riding in the first car, or directly behind the train’s locomotive, have a higher risk of exposure.

The study, which measured the air in coaches on the Richmond Hill line for ultrafine particles and black carbon, is set to be published in the Atmospheric Environment journal.

The study also found that the levels of ultrafine particles and black carbon inside the coaches were lower when the train was in push mode, which occurs when the locomotive is at the back of the train as opposed to the front.

Metrolinx has already been made aware of the study’s findings overtime and have been making various changes to combat the amount of pollution inside its trains’ coaches.

“We want to assure everyone who relies on GO Transit every day that we place the highest priority on their health and safety and we will continue to monitor and report on air quality to ensure we see improvements,” Metrolinx chief operating officer Greg Percy told the Star.

Following the Star’s initial article, Metrolinx has also published a statement in response to the study’s findings.

“The study notes the diesel locomotives tested are similar to those used by other public transit agencies in cities such as Vancouver, Chicago, San Francisco, Washington D.C., Boston, Los Angeles, and Seattle, so we’re hopeful this work will result in improvements that can be applied throughout the industry. It also notes that this is not an issue for trains that are being pushed by the locomotive from behind, which accounts for roughly half of our trips.“

Read the full statement here.