Ultrafine particles linked to over 1,000 deaths per year in Canada's two largest cities

A new study conducted in Canada's two largest cities has linked about 1,100 premature deaths per year to an unregulated air pollutant. Ultrafine particles (UFPs) primarily come from vehicle emissions and industrial activities. Canada's federal and provincial governments have not set concentration limits for UFPs, as they have for larger fine particles known as PM2.5.