The evolution of sulfur oxide levels and suspended particles in the air of the city of Valencia, 1979–1989

Abstract

The evolution of sulfur oxides and suspended particles (smoke and settleable materials) in the atmosphere of the Spanish Mediterranean city of Valencia, corresponding to the period 1979-1989, were determined. The contamination levels in industrial versus residential areas of the city were contrasted, as were the relative contributions of each zone to the mean total of each contaminant. Also determined were the mean annual concentrations of each contaminant in order to investigate long-term risks and the 98 percentile value in the case of short-term risk. Finally, a simple regression analysis was performed to find the inter-associations of these atmospheric contaminants and their relation to traffic density in each area. A decrease was observed in the emission levels of sulfur oxides and settleable materials in this period. On the other hand, the smoke levels were found to increase. A positive correlation was found between sulfur oxide concentration and traffic density. Likewise, no effectively reliable association was seen between smoke and traffic density.