Even low levels of air pollution increases risk of cancer
Prolonged exposure to particulate air pollution increases the risk of lung cancer even at levels below the European Union limit values, according to one of the largest studies of its kind published in The Lancet Oncology. In particular, there was a strong link to a type of lung cancer called adenocarcinoma, which frequently affect non-smokers.
The current study is based on the European Study of Cohorts for Air Pollution Effects (ESCAPE), which is coordinated by the University of Utrech in the Netherlands. Researchers from several departments at Karolinska Institutet participated in the Swedish part of the study, which was coordinated by the Institute of Environmental Medicine. In all, researchers used data from about 313,000 people in nine European countries. Air pollution concentration of particulate matter with a diameter of less than 2.5 micrometre (PM2.5), and less than 10 micrometre (PM10) was estimated at the participants' home addresses.
Sources of particulate matter air pollution include traffic, industry, and domestic heating. Participants were tracked for new lung cancer diagnoses in national and local cancer registries, and the researchers applied statistical modelling to separate the influence of air pollutants from other factors like smoking, diet, and occupation.
Among the participants, 2095 developed lung cancer during the average 13 years of follow up. The analysis showed that for every increase of 5 micrograms per cubic meter of PM2.5 pollution, the risk of lung cancer rose by 18%. For every increase of 10 micrograms per cubic meter in PM10 pollution the risk increased by 22%, with stronger effects indicated for adenocarcinomas.
According to the authors the association between particulate matter air pollution and the risk for lung cancer persisted also at concentrations below the existing European Union air quality limit values for PM10 (40 micrograms per cubic meter) and PM2.5 (25 micrograms per cubic meter).