A Europe-wide study indicates that even low levels of air pollution increase the risk of developing lung cancer. Ole Raaschou-Nielsen of the Danish Cancer Society Research Centre in Copenhagen, Denmark, who was involved in the study, said: “We found no threshold below which there was no risk.” ( The Australian , 10 Jul 2013). This is a concern given that the European Union has set the limits of safe air pollution at 25 μg per m3 of air for PM2.5 (particulate matter of less than 2.5 μm in diameter) and 40 μg per m3 for PM10.

The European Study of Cohorts for Air Pollution Effects (ESCAPE) used health data from 312,944 individuals in 17 European cohort studies. Air pollution levels were based on residential addresses and available land use information. During a mean follow-up of 12.8 years, 2,095 cases of lung cancer were diagnosed. The meta-analysis showed a significant association between lung cancer and PM10 concentrations (a hazard ratio of 1.22, with a 95% confidence interval of 1.03–1.45 per 10 μm per m3).

Although the risk of developing lung cancer from exposure to air pollution is low per individual, air pollution affects a large number of people and therefore has a substantial impact on public health. Takashi Yorifuji, of Okayama University Graduate School of Environmental and Life Science, Japan, stated: “At this stage, we might have to add air pollution, even at current concentrations, to the list of causes of lung cancer and recognize that air pollution has large effects on public health.” ( The Telegraph , 10 Jul 2013). This comment was strengthened by Jon Ayres, of the Institute of Occupational and Environmental Medicine in Birmingham, UK, who stated: “There is now no doubt that fine particles are a cause of lung cancer.” ( New York Daily News , 10 Jul 2013).