Probabilistic health risk assessment of polycyclic aromatic hydrocarbons and polychlorinated biphenyls in urban soils from a tropical city of India

Distribution of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in urban soils, and their risk for humans was evaluated and presented in this article. The average concentration of Sigma 16PAHs, Sigma carcinogenic PAHs, Sigma 28PCBs and Sigma dioxin-like PCBs was 631.6 +/- 244.5g kg(1), 568.8 +/- 238.8g kg(1), 11.57 +/- 2.00g kg(1) and 2.58 +/- 0.34g kg(1), respectively. Environmental and human health risk assessment parameters such as benzo(a)pyrene total potency equivalent (BaP TPE), index of additive cancer risk (IACR), life time average daily dose (LADD) and incremental lifetime cancer risk (ILCR) have been estimated and discussed. The average benzo(a)pyrene total potency equivalent (BaP TPE) estimate was 0.194mg kg(1) and ranging between 8.9x10(4) to 0.87mg kg(1). The incremental life time cancer risk (ILCR) of PAHs through soil ingestion for adults and children was estimated as 8.1x10(6) and 4.2x10(5), respectively. However, the cancer risk (ILCR) from non-dioxin-like PCBs and dioxin-like PCBs for adults and children ranged between 3.31x10(8) to 1.741x10(7) and 1.46x10(5) to 7.56x10(5), respectively. These estimated risks were lower than acceptable limits, based on incremental cancer risk from soil exposure. Overall, index of additive cancer risk (IACR) and hazard quotient (HQ) for PAHs and PCBs was lower than safe limit of 1, indicating no environmental and human health risk from PAHs and PCBs in this area of study.