Effects of particulate matter (PM) sources on mortality in Mediterranean cities: the MED-Particles project

Abstract

Background: Acute exposure to particulate matter (PM) has been linked to increases in mortality in several studies. Recently, some studies have examined which species and sources in the PM mixture are responsible for these associations, but this is not well documented in Southern Europe. The Mediterranean area has specific characteristics that influence air pollution levels and composition, such as highly urbanized areas with intense traffic, elevated sea traffic, intense solar radiation, and high frequency of wildfires and Saharan dust episodes. Aims: Examine the association between several PM sources and mortality in three Mediterranean cities. Methods: PM10 and PM2.5 concentrations were collected once or twice a week in three Spanish cities, Barcelona (2003-2010), Madrid (2007-2008) and Huelva (2003-2009). Source apportionment using positive matrix factorization was developed for both PM2.5 and PM10. A case-crossover regression analysis will be used to determine the effects of daily exposure to each source and non-accidental, cardiovascular and respiratory mortality for each city. Single-city estimates will be combined using meta-analysis. Results: Source apportionment resulted in three sources that were common in the three cities: traffic, mineral and industrial. Traffic accounted for 47%, 39% and 22% of PM2.5 concentrations in Barcelona, Madrid and Huelva, respectively. The city percentages were 9%, 18% and 13% for the mineral source. The industrial source was only detected in Barcelona and Huelva, where it accounted for 5% and 13% of PM2.5 concentrations. Similar percentages were found for PM10. Taken together, they common sources accounted for an average of between 56% and 71% of PM concentrations. Conclusions: Traffic is one of the main contributors to PM concentrations in the three cities. These sources will be linked to mortality in the subsequent analysis, including more cities, to provide the first multi-city study on health and PM sources in Europe. Acknowledgements: MED-PARTICLES EU LIFE10 ENV/IT/327