四川凉山藏彝青少年头发中多氯联苯污染水平的研究

Levels of Polychlorinated Biphenyls in Tibetan and Yi Adolescents' Hair from Liangshan Prefecture,Sichuan Province

本研究采用索式提取-气相色谱-质谱(GC-MS)分析了39份来自四川省凉山州藏族、彝族青少年(11~19岁)头发样品中的12种类二英多氯联苯(DL-PCBs)的浓度水平及其同族体组成,并分析了其浓度与民族、食肉和饮奶习惯及性别的相关性.结果表明,头发样品中PCBs的检出率为100%,DL-PCBs的总含量为(102.2±14.3)pg·g-1,含量范围9.6~991.6pg·g-1,表明该地区受到DL-PCBs的污染程度较轻.PCB-77、PCB-105、PCB-118为主要单体,占ΣDL-PCBs的84.7%.凉山州彝族青少年头发样品中的PCBs浓度显著高于藏族,且其浓度与每周食肉、饮奶频次具有相关性(P<0.05),表明通过饮食摄取的PCBs可能是造成浓度差异的原因之一.该地区藏、彝青少年女性发样中PCBs浓度显著高于男性(P<0.05).

Adolescents’( 11-19 years old) hair samples( n = 39) collected from Liangshan prefecture,Sichuan Province were analyzed for 12 dioxin-like polychlorinated biphenyl( DL-PCBs) congeners by gas chromatography-mass spectrometry( GC-MS). The levels and distribution characteristics of DL-PCBs in Tibetan and Yi Adolescents’ hair were studied,meanwhile,the relationships between the levels of DL-PCBs and the nationalities,eating habits and genders were addressed. The results indicated that the average concentration of PCBs was( 102. 2 ± 14. 3) pg·g-1with the range from 9. 6 pg·g-1to 991. 6 pg·g-1. The concentration levels of this region were relatively low. PCB-77,PCB-105 and PCB-118 were the major congeners,contributing to 84. 7% of the total. The levels of PCBs in Yi teenagers’ hair were higher than those in Tibetan,and the concentration in hair was related to the frequency of eating meats and drinking milk per week. It might be attributed to the different eating habits of these two nationalities. When gender was considered,significantly higher concentrations were found in female than in male( P < 0. 05).