上海崇明岛农田土壤中多氯联苯的残留特征

Residues of polychlorinated biphenyls in agricultural fields of Chongming Island in Shanghai

在上海崇明岛采集了101个耕层土壤样品,利用GC-μECD测定了8种多氯联苯(PCBs)浓度,并对其进行多元统计分析,探讨了其可能的污染来源.结果表明,样品PCBs浓度范围为n.d.～261ng/g,均值为56.0ng/g,低氯联苯含量和检出率均较高.不同土壤利用方式对PCBs残留量有一定影响,表现为水稻田土壤>大棚蔬菜西瓜田土壤>露天蔬菜西瓜田土壤.主成分分析和相关性研究结果显示,土壤中低氯联苯同系物间相关性较好,污染来源可能为同一类.

Residues concentration of 8 polychlorinated biphenyls（PCBs） congeners in 101 soil samples collected at Chongming Island of Shanghai were determined by GC-μECD.Concentrations of PCBs were between ND and 261ng/g with average of 56.0ng/g.Concentration and detection rate of low chlorinated homologues of PCBs were higher than high chlorinated homologues.Concentrations of PCBs varied with the changes of agricultural land use.Depended on the residue concentration level,the series of land use appeared as following：paddy soil〉green house vegetable and watermelon soil〉traditional vegetable and watermelon soil.Principal component analysis（PCA） and correlation analysis were introduced to investigate source of PCBs.The result showed that lower chlorinated homologues of PCBs were well correlated and implies that they maybe originate from similar sources.