Characterization and distribution of polycyclic aromatic hydrocarbon contaminations in surface sediment and water from Gao-ping River, Taiwan

Abstract

The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in water and sediment samples collected from 12 locations in Gao-ping River, Taiwan were analyzed. Molecular ratios and principal component analysis (PCA) were used to characterize the possible pollution sources. Concentrations of total 16 PAHs (ΣPAHs) in water samples ranged from below method detection limits (<MDLs) to 9.4 μg/L with the mean value of 0.43±0.75 μg/L ( n=48), which were predominated by two- and three-ring PAHs. The ΣPAH concentrations in sediments ranged from 8 to 356 ng/g-dry weight with the mean value of 80.6±31.8 ng/g ( n=48). Three- and four-ring PAHs including phenanthrene, anthracene and pyrene were the dominant species in sediment samples. High contents of PAHs were found in the estuary of the river and in the vicinity of industrial areas. Ratios of specific PAH compounds including phenanthrene/anthracene (Phe/Ant), fluoranthene/pyrene (FL/Pyr), chrysene/benzo[a] anthracene (Chr/BaA), low-molecular-weight PAH/high-molecular-weight PAH (LPAH/HPAH) were calculated to evaluate the possible sources of PAH contamination. These ratios reflect a mixed pattern of pyrolytic and petrogenic inputs of PAHs in Gao-ping River. The petrogenic PAHs may be mainly from the leakage of crude oil and the refined products from urban vehicle traffic, while the pyrolytic PAH input is located in the proximity near the mouth of estuary of the River. The PCA analysis confirmed that petrochemical industrial parks located in the vicinity of estuary of Gao-ping River might be the possible source for the PAH input.