High levels of airborne particles recorded at Montreal's Trudeau airport

A McGill University study found a particularly high number of airborne particles on the grounds of Montreal's Pierre Elliott Trudeau Airport — including nanoparticles of heavy metals that are harmful to human health.

The findings, published in the latest issues of the scientific journal Environmental Pollution, are based on data collected from July to September 2017. The researchers recorded up to two million particles per cubic centimetre — higher than measurements taken in downtown Montreal and on major Montreal highways at rush hour, the study found.

McGill Prof. Parisa Ariya, who teaches in both the departments of chemistry and atmospheric and oceanic sciences, said the results more research is needed, quickly.

"Further studies should be performed in the future, and also very soon, to make sure that the impacts are not very elevated regarding health," Ariya said.

Difficult to detect

The metal and metal oxide particles detected were tiny — nanoparticles, less than 100 nanometres in size (or 0.0000001 metres).

The nanoparticles are so small, they have been been impossible to observe in the past, Ariya said, and even today, few researchers have the tools to measure them. The McGill team use a high-resolution scanning electron microscope.

Few other international airports have been subjected to such a high level of analysis, Ariya said. 

As a result, the level of potentially hazardous airborne particles detected at Trudeau airport is higher than that found to date at any other international airport, according to the study.

Ariya said this could be due to the high number of flights to and from Trudeau airport, the proximity of the airport to the city centre and the fact that Montreal is located on an island.

Health impacts

More than 30 chemical elements were detected in the airborne particles measured in the study.

While some of these elements are "not dangerous at all," according to Ariya, others are considered toxic by the United States Environmental Protection Agency.

Researchers found concentrations of zinc, nickel, iron and lead, as well as other heavy metals such as chromium, manganese and arsenic.

"Nanoparticles in the air are considered emerging contaminants because they are known to have health effects," she said.

Aéroports de Montreal (ADM), the organization that runs the airport, said its environment and sustainable development division would follow up on the results of the study with researchers over the coming weeks.

"This research is part of our desire to continue our development while minimizing our ecological footprint," ADM spokesperson Marie-Claude Desgagnés said.