上海崇明农业土壤中共平面多氯联苯的初步研究

采用同位素稀释质谱法,用高分辨率气相色谱-高分辨率质谱仪(HRGC-HRMS)对上海崇明农业土壤中12个共平面多氯联苯(co-PCBs)的含量进行了测定,并且对可能的来源进行了初步探讨。31个农业土壤中co-PCBs浓度范围为24.86~814.50 pg/g,平均值为92.65 pg/g,毒性当量浓度(I-TEQ)为0.032~0.486 pg/g,平均值为0.142 pg/g。经过比较,其浓度远远低于国内外污染土壤水平,和一般的农业土壤水平比较接近,认为该地区基本未受co-PCBs的污染。其中个别位点的毒性当量浓度较高,认为有必要对该地区可能的来源进行分析。主成分分析结果表明,崇明土壤co-PCBs可能来自市售Arcolor和各种燃烧,包括室内煤炭、木料燃烧以及固体或医疗废物燃烧的影响。作为生态岛屿建设的崇明,需要特别关注防止土壤中的co-PCBs进一步升高降低生态系统良性循环的完整性。

Coplanar PCBs in Agricultural Soils in Chongming Island

31 agricultural soil samples were collected in 2007 from Chongming Island,Shanghai,and concentrations of coplanar polychlorinated biphenyls(co-PCBs) were determined by HRGC-HRMS.Results indicated that total concentrations ranged from 24.86 to 814.50 pg/g dry weight with a mean of 92.65 pg/g(dw).Total TEQ ranged from 0.032 to 0.486 pg/g with a mean of 0.142 pg/g which was much lower than contaminated soil and similar to agricultural soils of other districts.So generally Chongming was thought not co-PCBs contaminated.However TEQ of sampling sites C8 and C31 was relatively higher than that of other sites,it is necessary to study possible sources.Principal component analysis(PCA) suggested that the other pollution sources of PCBs existed such as housecoal,hardwood combustion and municipal solid waste and medical waste combustion besides PCB(Arcolor).Construction as an ecological island of Chongming,requires special attention to prevent further increase of co-PCBs in soil,reducing the integrity of a healthy ecosystem.