Female lung cancer mortality and long-term exposure to particulate matter in Italy.

Background: Outdoor air pollution and particulate matter (PM) have recently been classified in Group 1 by IARC. In Italy there is no epidemiological study on the association between female lung cancer and PM as measured by the official monitoring stations. Methods: We estimated the dose-response relationship between female lung cancer mortality and available long-term outdoor PM10 and/or PM2.5 concentrations for all the Italian province capital city municipalities (respectively, 64 and 32 municipalities). Multiple regression analysis of standardized mortality rates (SMRates) for the period 2000-11, as a function of PM concentrations, considering percentage of smokers and deprivation index as additional explanatory variables, was performed for PM10 only. Results: The number of province capital cities with available PM2.5 data was not sufficient to detect a significant increment of SMRates as a function of concentrations. An SMRate increase of 0.325 for 1 µg m^-3 increment of PM10 concentration was calculated. Moreover, the attributable risk of the overall SMRates for the two subgroups of municipalities under/equal and above 20 µg m^-3 value was evaluated. Attributable deaths were computed by both the unitary SMRate increase and the attributable risk. A rough estimate of the impact of PM10 exposure at level above the WHO guideline value of 20 µg m^-3 in these 64 municipalities is between 2920 and 3449 lung cancer deaths out of 22 162 (13-16%). Conclusion: Maintaining the PM10 concentrations below such WHO recommendation, an overall saving of nearly 300 lung cancer deaths per year in a population of 8 146 520 women living in the municipalities at study has been evaluated. [ABSTRACT FROM AUTHOR]