Geochemistry and origin of PM10 in the Huelva region, Southwestern Spain.

The results of chemical analysis of PM(10) atmospheric dust samples collected between July 2001 and June 2002 in rural and urban background monitoring stations in Huelva (South-western Spain) are reported. In order to identify the sources and quantify their contribution to PM(10), principal component analysis and receptor modelling techniques were performed using independent variables of the complete series of concentrations of PM(10) contents. The Ria of Huelva is considered to be one of the high industrial estates in Spain, where several metallurgical, petrochemical and fertilizer industrial estates are located, surrounded by areas of a high ecological interest such as Doñana National Park. Annual means of 29-33 and 37 micro g PM(10)m(-3) were obtained for the study period in rural and urban monitoring stations, respectively. These values are below the mean annual limit value for 2005 and onwards from the Directive 1999/30/EC [EU, 1999. 1999/30/CE Council Directive relating to limit values for sulphur dioxide, nitrogen dioxide and oxide of nitrogen, particulate matter and lead in ambient air. The Council of the European Union]. High PM(10) episodes in rural and urban areas occurred during African dust events. Episodically, the emissions of plumes from industrial estates reach rural areas causing peak episodes of PO(4)(3-) Cu, Ti Pb and As. Anthropogenic particles arising from metallurgical emissions (pyrite, chalcopyrite and sphalerite) were observed in the rural sites. The annual mean As concentrations measured in PM(10) in the city of Huelva and surrounding rural areas (144 and 84-51mg Askg(-1) in PM(10), respectively) are several times high the concentrations obtained in other Spanish monitoring stations (7-57mg Askg(-1)). The source apportionment analyses allowed the quantification of the contribution to PM(10) of an industrial mixed source in the rural background.