Analysis, source identification and health risk assessment of polychlorinated biphenyls (PCBs) in surface soils from different land types of northern, eastern and western parts of city of Tehran, Iran

Polychlorinated biphenyls (PCBs) are a group of persistent organic pollutants that due to their characteristics including bioaccumulation potential and persistence in the environment; can pose adverse effects on human and environmental health. Therefore, this study was performed to analysis, source identification and health risk assessment of PCBs in surface soil samples collected from some land types of northern, eastern and western parts of city of Tehran in 2019.

In this descriptive cross-sectional study, a total of 45 surface soil samples were collected from 15 sampling sites including business districts, residential areas, cultural and educational areas, public green space and roadside. After extraction of analytes, the gas chromatography/mass spectrometry (GC–MS) method was used to determination of PCBs in the soil specimens. All statistical analyses were performed using the SPSS software.

Based on the results obtained, 13 congeners of PCBs were detected in the analyzed soil samples. Also, the minimum, maximum and mean concentrations of ∑13PCBs (µg/kg) were 0.031, 23.1 and 6.77, respectively. Moreover, the results of principal component analysis (PCA) and significant distribution of low molecular weight homologues of PCBs in the analyzed soil samples indicated that the presence of PCB compounds in the soil samples would be connected with combustion processes in the soil. Besides, since among the detected PCBs, the TEF values only established for PCB189, therefore, exposure to contaminated soil with this congener could be lead to a "very low level of carcinogenic risk".

Given that PCBs have adverse effects on the environment and human health, detection, content determination, source identification and periodic monitoring of these compounds in different mediums especially water and soil for human and environmental health maintenance are recommended