Occurrence of polycyclic aromatic hydrocarbons in groundwater from rural areas in eastern China: Spatial distribution, source apportionment and health cancer risk assessment

Polycyclic aromatic hydrocarbons (PAHs) pollution in well water has become more widespread, especially in rural areas. The development of small workshops has brought economic growth; however, a sharp increase in the level of pollution due to combustion of fossil fuels has also been observed. A lack of effective measures to control environmental pollution and strict legislation in these regions can contribute to higher PAHs emissions. In the study, the distribution and level of 16 PAHs in well water in rural eastern China were reported. The total concentrations of 16 priority PAHs varied from 4 to 169 ng/L, and an arithmetic mean of 38 ± 25 ng/L. Moreover, the highest PAHs content was found in well water from Shandong Province, and the average concentration was 60 ± 48 ng/L. The distribution of total 16 PAHs illustrated a decreasing trend from north to south. However, the distribution of PAHs with 2-rings and 4-rings was found to be higher in Jiangsu and Hebei province, respectively. The PAHs source identification results showed that the dominant source was coal and biomass combustion, which was consistent with the local conditions. The values of health cancer risks (CRs) were calculated, and that indicated that hazard quotients of nine non-carcinogenic contaminants were lower than one and might not have negative health risks. However, for carcinogenic PAHs, CRs values of the dermal pathway were higher than 10−6, and those for benzo [a]pyrene (BaP) and dibenzo [a, h] anthracene (DbA) were even higher (>10−4), indicating significant high risks to children and adults.