Study of the profile of polycyclic aromatic hydrocarbons in atmospheric particles (PM10) using multivariate methods

The scope of the present study is to identify and quantify the main sources of polycyclic aromatic hydrocarbons (PAHs) in the Candiota region, Rio Grande do Sul, Brazil. Four sampling sites at a distance of 50 km from the emission source were selected: Aceguá, Aeroporto, 8 de Agosto and Pedras Altas. Samples were collected from February 2001 to October 2001, using an HV PM10 sampler for high volumes during a continuous period of 24 h every 15 days. The filters containing the particulate matter were extracted with dichloromethane in soxhlet and later analyzed by gas chromatography/mass spectrometry (GC/MS). The average concentrations of PAHs varied from 0.051 to 1.791 ng m−3. The analysis of their distribution amongst the main emission sources was done through the diagnosis of concentration ratios of PAHs, as well as using statistical methods like factor analysis. The statistical analysis separated the 13 compounds studied in 3 Factors, grouping under Factor 1 emissions from the combustion of coal and wood, under Factor 2 vehicular emissions from the combustion of diesel oil and gasoline and under Factor 3 emissions from unburned diesel oil and gasoline.