Polycyclic aromatic hydrocarbons in a bioassay-fractionated extract of PM10 collected in Sao Paulo, Brazil

Polycyclic aromatic hydrocarbons (PAHs) were measured in airborne particles (PM [0) collected in an urban site of Sao Paulo City, Brazil. Samples were Soxhlet extracted sequentially with dichloromethane and acetone, followed by solid phase fractionation. Increasing polar fractions (A-K) of dichloromethane and acetone extracts were obtained. Fractionated extracts were analyzed by gas chromatography/mass spectrometry and Salmonella microsuspension bioassay. Sixteen PAH compounds were quantified in dichloromethane B and C fractions, nevertheless the D and E fractions presented higher mutagenic activities. Concentrations of the individual PAHs ranged from 0.8 ng m(-3) (perylene) to 12.8 ng m(-3) (benzofluranthene), reaching a total concentration of 95.5ng m(-3). BaP/BgP and Pyr/BaP ratios indicated the presence of vehicular emissions and BghiP/Ind and Chr/BeP ratios suggested a contribution of wood combustion emissions. Further investigation is still necessary for a better understanding of the PAH sources in the urban atmosphere of Sao Paulo City. (C) 2002 Elsevier Science Ltd. All rights reserved.