Polycyclic aromatic hydrocarbons (PAHs) in airborne particulate matter in Curitiba, Brazil and benzo(a)pyrene toxic equivalency factors (TEFs).

The concentration of PAHs in particulate matter was investigated in the city of Curitiba, located in south of Brazil. Urban atmospheric particulate matter was collected at six sampling sites whose characteristics were representative of the prevailing conditions. The concentration of particulate matter varied from 11.02 to 177.27 ng/m(3). Particulate matter was basically composed of PAHs with 3 and 4 aromatic rings and it agrees with results of air quality monitoring performed in other cities around the world. Molecular ratios, such as (Benzo(ghi)Perilene/Indene(cd)Pyrene, B(ghi)P/I(cd)P, indicate that the source of PAHs is gasoline engines in the downtown area and diesel engines in surrounding sites representing a heavy traffic situation. It was also investigated the toxic level of particulate matter using the BaP equivalency factor. The BaP(eq) for all samples was between 0.42 to 1.12 ng/m(3). The equivalency BaP(eq) indicated low health risk associated with exposure to the total PAHs content in environmental air.