Characterization and Risk Assessment of Polycyclic Aromatic Hydrocarbons in Surface Water from Liaohe River, Northeast China

Abstract

ABSTRACTIn this study, the characteristics, probable source, and potential carcinogenic risk of 16 polycyclic aromatic hydrocarbons (PAHs) in surface water of the Liaohe River were investigated. Twelve sampling points were selected, and water samples were collected in both dry and flood periods of 2011. Sample analysis indicated that the concentration of total PAHs varied from 840.50 ng/L to 4274.73 ng/L in the flood period, and from 387.76 ng/L to 1997.83 ng/L in the dry period. The representative PAHs in the flood period were benz[a]anthracene (Baa), naphthalene (Nap), and chrysene (Chr), whereas Phenanthrene (Phe), fluoranthene (Flu), and pyrene (Pyr) were the representative PAHs in the dry period. The compositional pattern of PAHs indicated that four-ring PAHs were predominant in the flood period, whereas three-ring and four-ring PAHs dominated in the dry period. The different PAH congener ratios indicated that PAHs in surface water of the Liaohe River mainly originated from a mixed source in the flood period, and from combustion in the dry period. Based on the methods of Incremental Lifetime Cancer Risk (ILCR) and the benzo[a]pyrene toxic equivalent (TEQ), the potential cancer risk was quantitatively assessed, and the results suggested that there was a potential cancer risk in surface water of the Liaohe River and more attentions must be paid to the PAHs contamination. The cancer risk in the teenager group was the most, followed by the children group, adult group, and infant group, and toddler group was the least.