采煤沉陷区水体有机氯农药的污染特征及风险评价

Pollution Characteristics and Risk Assessment of Organochlorine Pesticides in Water Bodies in Coal Mining Subsidence Area

为研究采煤塌陷水域不同深度水体有机氯农药(organochlorine pesticides,OCPs)的污染特征及风险评价,使用气相色谱-质谱联用仪(gas chromatography-mass spectrometry,GC-MS)对淮南谢桥矿农田塌陷区水体中的OCPs进行质量浓度测定,利用ArcGIS进行OCPs特征污染物六六六(hexachlorocyclohexanes,HCHs)和滴滴涕[2,2-bis(p-chlorophenyl)-1,1,1-triehloroethane,DDTs]分布特征及来源研究,并选择美国环境保护署(EPA)推荐的健康风险评价模型进行评价。结果表明:OCPs平均含量范围为583.45~797.62 ng/L,悬浮物中OCPs平均含量范围为418.03~610.11 ng/L,整体呈现出由表层到底层逐渐递增的趋势,研究区水域的OCPs质量浓度在中国水域中处于中等偏上水平,水体中HCHs主要来源于近期林丹等杀虫剂的使用,DDTs主要来源于农业三氯杀螨醇的污染。水体的非致癌健康风险指数为2.320×10^(-3)~6.813×10^(-3),致癌健康风险指数为6.814×10^(-7)~1.575×10^(-6),表明沉陷区水体中OCPs对人体未达到致癌风险。

In order to study the pollution characteristics and risk assessment of organochlorine pesticides(OCPs)in water bodies of different depths in coal mining subsidence waters,gas chromatography-mass spectrometry(GC-MS)was used to determine the mass concentration of OCPs in the water bodies of the farmland subsidence area of Huainan Xieqiao mine,and ArcGIS was used to carry out OCPs characteristic pollutants.The distribution characteristics and sources of hexachlorocyclohexanes(HCHs)and 2,2-bis(p-chlorophenyl)-1,1,1-triehloroethane(DDTs)were studied,and the health risk assessment model recommended by the United States Environmental Protection Agency(EPA)was selected for evaluation.The results show that the average content of OCPs range from 583.45 ng/L to 797.62 ng/L,and the average content of OCPs in suspended solids range from 418.03 to 610.11 ng/L,showing a gradual increase from the surface to the bottom.The mass concentration of OCPs in the waters of the study area is in the upper-middle level among the research rivers in China,which belongs to the high pollution level.HCHs in the water body are mainly derived from the recent use of lindane and other pesticides,and DDTs are mainly derived from the pollution of agricultural dicofol.The non carcinogenic health risk index of water body is 2.320×10^(-3)~6.813×10^(-3),the carcinogenic health risk index is 6.814×10^(-7)~1.575×10^(-6),indicating that OCPs in the water body of the subsidence area do not reach the risk of carcinogenesis to human body.