Distribution and ecological risk assessment of PAHs in rivers of Yanweiwan Village,Huzhou

Abstract:

In order to research pollution characteristics, sources and ecological risk assessment of polycyclic aromatic hydrocarbons (PAHs) from the rural rivers around the Taihu Lake, water and sediment samples were collected from 10 stations in Yanweiwan Village, Huzhou City, a typical rural area around the Taihu Lake. The content and composition of 16 priority PAHs were detected by high performance liquid chromatography (HPLC). The results showed that the survey area was at the medium to low PAHs pollution level and at the low risk, compared with other areas. According to the analysis of the distribution characteristics of PAHs pollution in water, the three sites with the highest mass concentration were the mixed areas of industrial and residential areas, respectively reaching 958.39 ng/L, 685.97 ng/L, 858.57 ng/L, and the PAHs were primarily composed of 2-3 rings. The results of characteristic ratio and principal component analysis indicated that PAHs mainly originated from combustion of straw and coal, and partly from oil pollution. The result of ecological risk assessment of sediments indicated that more than 80% of the area were considered risk-free,and a few areas maybe had a weak ecological risk, and serious ecological risk did not exist. The carcinogenic risk of the survey area was assessed by the carcinogenic equivalent mass concentration (TEQ). Results demonstrated that the industrial area and the garbage station had high potential carcinogenic risk, and the calculated mass concentration TEQ were 2.04 ng/m³ and 1.76 ng/m³ respectively.