柳州岩溶地下河水体有机氯农药分布特征

Distribution characteristics of organochlorine pesticides in karst subterranean river in Liuzhou

采用气相色谱（配ECD检测器）对柳州鸡喇和龙寨两条岩溶地下河不同位置水体中18种有机氯农药（OCPs）组分进行分析。结果表明,除异狄氏剂醛外,其余17种OCPs均有不同程度检出,OCPs浓度变化范围为107.68~1101.55ng/L,均值为532.515ng/L。OCPs主要组分为：α-HCH、β-HCH、γ-HCH、δ-HCH、p,p＇-DDE、o,p＇-DDT、p,p＇-DDD、p,p＇-DDT、六氯苯、七氯、艾氏剂。其中DDTs和HCHs含量最高,二者之和占到总OCPs的75.8%~96%。对其污染源进行分析,发现地下河水体中DDTs主要源自土壤。HCHs来源相对复杂,可能源于工业品或者长距离大气运输,也可能是近期有林丹的输入使其浓度增高。与国内外各水体相比,本次研究的两条岩溶地下河有机氯农药含量相对较高。

Water samples collected from different positions of two subterranean rivers in Liuzhou Karst Area are tested for 18 kinds of organochlorine pesticides（OCPs） by gas chromatography coupled with an electron capture detect （GC/ECD）. The results show that except dieldrin aldehyde, 17 kinds of OCPs are detected in different levels and the OCPs concentration range from 107. 68 to 1 101. 55ng/L, with a mean value 532. 515ng/L. Main OCPs are α-HCH, β-HCH, γ-HCH, δ-HCH, p,p＇-DDE, o,p＇-DDT, p,p＇-DDD, p,p＇- DDT, HCB, Heptachlor, Aldrin. Content of the DDTs is the highest. HCHs and OCPs account for 75.8%-96% of the total. Meanwhile, the origins of organochlorinated pesticides in the water are investigated. DDTs mainly comes from soils. HCHs source is relatively complex, probably originated from industry or long atmospheric transport. Recently use of lindane can also make HCHs input concentration increase. Comparing concentration of OCPs in different kinds of water from the world, organochlorine pesticides content is relatively at high level in these two karst underground rivers.