Despite the documented effectiveness of the N95 mask in filtering fine particles emitted by forest fires, which cause a decrease in air quality in several regions of Quebec, the wearing of it by the population of sectors concerned is not recommended by the national director of public health, Luc Boileau.
” Levels [de polluants] to which we are exposed are not extremely high,” notes Luc Boileau, in an interview with Duty Tuesday. In this context, the expert and his team do not consider it necessary to recommend that Quebecers in regions affected by smog wear an N95 mask, even if several studies demonstrate its effectiveness.
During the night from Monday to Tuesday, the air quality deteriorated greatly in the greater Montreal area and in the Outaouais, among other things, due to the forest fires that have been raging for a few days in the north of Province. In the metropolis, which was covered in a thick cloud of smog on Tuesday, the air quality index reached around 80 in the early afternoon in the city center. This index – deemed “bad” when it exceeds 50 – is determined by analyzing the concentration of five pollutants present in the atmosphere, such as carbon monoxide and fine particles.
If this concentration of pollutants is considerably above normal, it remains limited, tempers Alexandre Barris, toxicologist at the Regional Directorate of Public Health in Montreal. In this context, wearing a mask outside “is really not one of our recommendations at the moment”, he indicates. A position shared by Luc Boileau, who specifies that the concentration of pollutants in the air should be much higher for the wearing of the N95 mask to be recommended outdoors by Public Health.
Risks
However, exposure to smog for several hours can have negative health effects that can lead, in some cases, to hospitalizations. “The people who most often arrive at the emergency room because of the smoke are the outside workers”, specifies the Dr Stéphane Trépanier, director of public health at the CISSS de l’Abitibi-Témiscamingue. A university study conducted in 2021 has also shown that Canadians are more at risk of being victims of premature deaths related to exposure to air pollution generated by forest fires, which would also increase the risk of being preyed upon. lung or brain cancer, according to another study.
Thus, “if for more essential work you have to be outside for an extended period, it is always possible to use an N95 mask, but it is not something that is generally recommended for the population. of Abitibi-Témiscamingue,” noted Mr. Trépanier. In addition, while the effectiveness of the N95 mask in filtering pollutants emitted by forest fires has been demonstrated by several university studies, surgical masks and cloth face coverings are “really not effective” , recalls the Dr Luc Boileau.
Respirologist and professor at the University of Ottawa Shawn Aaron believes, for his part, that Quebec Public Health should recommend more wearing the N95 mask to people at risk who go outside during episodes of smog. “I think Public Health should warn people at risk, those with illnesses, children and the elderly, to limit their outdoor activities and that if they are outside for more than 30 minutes, they must wear a N95 mask,” he insists.
In general, “even people in good health” should be careful “not to do high-intensity activities outside,” recalls Éric Lavigne, who is an adjunct professor at the School of Epidemiology and of public health from the University of Ottawa. He also recommends that people working several hours outside wear a mask, “preferably the N95”. “It’s really the type of mask that will protect us best. »
