AUTHOR=Jianrong Cao , Yanjun Liu , Sujie Yu 

TITLE=The concentrations and sources of PAHs and PCBs in soil from an oil field and estuary in the Yellow River Delta, China

JOURNAL=Frontiers in Environmental Science

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2022.1028299

DOI=10.3389/fenvs.2022.1028299

ISSN=2296-665X

ABSTRACT=This study was conducted to assess the occurrence of organic pollutants (i.e. polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs)) in the soil samples collected from  two sub-regions (an oil field and the Yellow River Estuary) in the Yellow River Delta (YRD), China. The concentrations of PAHs and PCBs in the soil were in the range of 157.8-481.7 μg kg-1 (dry weight) and 5.6-56.6 μg kg-1 (dry weight), respectively. The average concentration of PAHs in the soil samples from the oil field were 274.0 μg kg-1, and that in the estuary soil samples were 244.4μg kg-1. The average concentration of PCBs in the soil samples from the oil field and the estuary were 24.2 μg kg-1 and 10.8μg kg-1, respectively. The contribution of low molecular weight PAHs (two-ring and three-ring PAHs) was larger in the soil samples from the oil field than that in the estuary soil samples. Both PAHs and PCBs contaminations in the estuary area were lower than that in the oil field area. By using diagnostic ratios analysis, the main source of PAHs was attributed to petroleum input caused by the fuel oil or light refined petroleum products in the Gudong Oilfield. The amount of low-chlorine congeners (3-4 chlorine atoms) PCBs in soil samples from the oil field were higher than that in the estuary soil samples. The congeners analysis of PCBs and the correlation analysis between the concentrations of PCBs and PAHs were employed. The results indicated that the emission of PCBs in YRD were influenced by both Godong oilfield and other industrial sources.