《Spatial distribution, source identification, and human health risk assessment of PAHs and their derivatives in soils nearby the coke plants》
Website:https://doi.org/10.1016/j.scitotenv.2022.160588
Graphical Abstract:
ABSTRACT:
The coking industry can generate large amounts of polycyclic aromatic hydrocarbons (PAHs) and their derivatives, which may negatively impact the environment and human health. In this study, soils nearby a typical coking plant were sampled to assess the impact of coke production on the surrounding residential areas and human health. The mean concentration of PAHs and their derivatives in residential area soils nearby the coking plant was 4270 ng/g dw, which was 1 order of magnitude higher than that observed in areas far from the coke plant and approximately 4 times lower than that revealed the coke plant. In addition, the results showed that the coking processing area was the most contaminant area of the coke plant (mean: 74.4 μg/g dw), where was also the main source of pollutants in residential areas. In terms of vertical soils in coking plant, the maximum levels of chemicals (mean: 205 μg/g dw) were presented at the leakage of underground pipelines, where were much higher than those in surface soils, and decreased with the increase of depth. The analysis of variance (ANOVA) results showed that there were obvious differences in the concentrations of 6-nitrochrysene between the plant, residential areas and the control areas. Meanwhile, 6-nitrochrysene had potential cancer risk (CR) for human in the coking site. Thus, 6-nitrochrysene was the most noteworthy among PAH derivatives. Furthermore, the CR (mean: 5.94×10-5) and toxic equivalent quantities (TEQs) (mean: 14.8 μg·TEQ/g) of PAHs and their derivatives was assessed in this study. This finding suggested that PAHs and their derivatives especially those extremely toxic chemicals (Nitro-PAHs (NPAHs) and Br/Cl-PAHs (XPAHs)) might pose a potential health risk to residents nearby the coke plant. The current study provides further insights into the pollution characteristics of PAHs and their derivatives in coke plants and potential risks to the workers and surrounding residents.