Health risk assessment of inhabitants exposed to PAHs particulate matter in air

Abstract

The presence of polycyclic aromatic hydrocarbon compounds (PAHs) was investigated in the particulate matter of samples taken at six sampling sites in the city of Curitiba (southern Brazil). The concentrations of suspended particulate matter ranged from 11.02 to 177.27 ng/m³. The analysis showed that 14 of the 16 PAHs are considered a priority compound by the USEPA (US Environmental Protection Agency). The mixture of PAHs was predominantly composed of PAHs with 3 and 4 aromatic rings. Isomer pair ratios show that the main source of PAHs was from burning fossil fuels (gasoline and diesel oil), although other sources may have contributed also. Benzo(a)pyrene, (BaP), regarded one of the most toxic PAHs, was present in all samples, but with concentrations lower than the maximum concentrations defined by some EU Countries. The risk assessment was conducted using the toxic equivalent factor (TEF) considering the toxicity of the individual PAHs compared to BaP. The BaP_eq for all samples was between 0.42–1.12 ng/m³. The equivalent BaP_eq indicated low health risk associated with exposure to the total PAHs content in air. The incremental lifetime cancer risk (ILCR) model was used to find the risk level for workers close to the emitting pollution sources. Outdoor exposure showed no risk for the amount of PAHs emitted. The acceptable risk is 10⁻⁶; however, all results were lower than this value.

Keywords:

• PAHs
• inhalation exposure
• risk assessment
• ILCR
• particulate matter
• air quality
• TEFs
• benzo(a)pyrene
• cancer risk
• outdoor exposure

Acknowledgments

To CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) for financial support (Grant 473238/2008-0 and 577060/2008-2).