October 17th 2017, The McGill Daily said in an article that Montreal was the second worst city in Canada for air pollution. It is the second most polluted right behind the town of Sarnia, Ontario. Sarnia, Ontario is an industrial city which explains why it would be number one. The World Health Organization (WHO) is the creator of the ranking of the most polluted cities of Canada. Although Montreal has a low ranking Canada still ranks third in the world for air quality according to the same organization.