Chemical characterisation and source apportionment of PM2.5 and PM10 at rural, urban and traffic sites in Navarra (North of Spain)

PM10 and PM2.5 levels, concentrations of major components, trace elements, pH, conductivity and source apportionment were evaluated from samples collected during 2009 at three different locations (rural, urban and urban-traffic) in Navarra (North of Spain). Mean particulate matter concentrations were below the annual limit value for PM10 and annual target value for PM2.5 established by the European Directive 2008/50/EC and similar to those recorded at other locations in the North of Spain. The major components of PM10 in the three sampling stations were, by order of importance, OC + EC, NO3- and non-marine sulphate (nmSO42-), whereas the major components of PM2.5 were OC + EC, nmSO42- and NO3-. Delta pH values indicated that PM2.5 samples were more acidic than PM10 ones. The 90-96% of total trace elements contribution in PM2.5 and PM10 were described by P, Ti, Cr, Mn, Ni, Cu, Zn, Sr, Sn, Ba and Pb. Concentrations of those elements were lower than values obtained in Pamplona in 2002-2004 and similar to those found in other sub-urban and urban Spanish cities. PMF model identified 5 principle sources for PM10 and PM2.5 in Iturrama and Plaza de la Cruz (crustal, secondary sulphate, secondary nitrate, traffic and sea-salt aerosols) and 4 sources for PM10 in Bertiz (crustal, secondary sulphate, secondary nitrate and sea-salt). (C) 2011 Elsevier B.V. All rights reserved.