Does outdoor air pollution cause lung cancer deaths? IARC says it does. It is an historical day for epidemiology, toxicology and public health – this 17^th of October – since the greatest world authority on carcinogenic agents presented in Paris the results of monograph n. 109 about outdoor air pollution. Classified as Group 1, i.e. carcinogenic for humans, outdoor air pollution is now considered as dangerous as vinyl chloride, asbestos, formaldehyde or ionizing radiations.