额尔古纳河水域表层水体六六六类农药的残留与分布特征

Residues and distribution characteristics of hexachlorocyclohexanes in surface water from Erguna River Basin

利用SPE-GC-ECD方法对额尔古纳河流域表层水体六六六类(HCHs)农药的残留进行测定,分析其分布特征,并且初步确定了组成特征以及来源。结果表明,额尔古纳河流域4种六六六类农药均有不同程度的检出,检出频率最高的是α-六六六,额尔古纳河流域六六六类农药总量浓度范围在N.D～4.5ng/L之间,属于自然浓度背景水平。分析总量浓度变化趋势以及异构体组成情况,额尔古纳河流域六六六类农药属于面源污染。考虑到湿地通常为污染物沉积的汇,也是释放产生的源,所以额尔古纳河流域中的六六六类农药来自于二卡湿地通过沉积物冲刷、水体交换释放。

The contents of hexachlorocyclohexanes(HCHs) from 22 samples in Erguna River Basin were measured by Solid Phase Extraction-gas chromatographyelectron Capture Detection (SPE-GC-ECD) According to the distribution characters,component characterstics and source apportionment of HCHs were confirmed.The results shows:4 HCHs were founded in almost every sample from Erguna River Basin,α-HCH was the highest frequently detected HCHs.The concentration of total HCHs in the surface water of the studied River Basin ranged from Not Detected to 4.5ng/L,it belongs to the natural background.Though analyzing the total concentration changing and the characters,from the studied River Basinshows that the pollutant belongs to the non-point source pollution.Consideringthat the wetland is usually the sink as well as the source of the release of the pollutant,the HCHs in the Erguna river basin may comes from er-ka wetland which is released by sediment erosion and water exchange.