title: Canadian urban air quality, 1971--1975.
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000032:analysis*; D002170:Canada; D004782:Environmental Health; D006262:Health; D006801:Humans; D012621:Seasons; D014504:Urban Health
chemical_list: D000393:Air Pollutants