某水域鱼样中PCDDs和PCDFs污染的调查

INVESTIGATION ON PCDD/FS CONTAMINATION LEVEL IN 31 FISH SAMPLES FROM A TYPICAL WATER AREA.

目的:采用较大样品量首次对我国某水域的鱼样品进行二恶英污染水平的现状调查研究,发现同系物指纹特征,并对二恶英膳食暴露进行了初步估算。为制定我国食品二恶英污染限量标准提供和积累重要的基础数据。方法:依据美国国家环保局标准方法EPAl6 13所界定的HRGC/HRMS技术对样品中的PCDDs/Fs进行定性和定量分析。结果:以湿重计算的总PCDD/Fs平均浓度是2 38pg/g ,以WHO TE 9计算所得的平均浓度是0 35pg/s。研究发现,不同种类的鱼样品间PCDD/Fs水平相差很大。OCDD ,2 ,3,7,8—TCDF是二恶英同系物中最主要的优势污染同系物。其毒性的主要贡献以1,2 ,3,7,8—PeCDD、2 ,3,4 ,7,8-PeCDF为主。在污染同系物分布上以二恶英类化合物为主。该地区人群摄入鱼的二恶英PCDD/Fs的平均膳食暴露量的估算是0 6 3pgWHO TEQ/kgBW·day。与欧盟制定的限量标准相比(1 0pgWHO -TEQ/g) ,个别鱼体中的二恶英平均污染水平超过该限量标准。结论:该水域中的鱼已受到了一定程度的PCDD/Fs污染。应该全面开展各类食品中二恶英污染现状的研究,以制定适合我国国情的食品二恶英限量标准,保护人们健康。

Objective:To study and evaluate PCDD/Fs contamination level primarily in a typical water and PCDD/Fs dietary intake from fish for local people,and then to provide a foundational data for national PCDD/Fs limit standard in fish.Methods:Dibenzo-p-Dioxins and Dibenzo-Furans in fish samples was performed and analysed by isotope dilution HRGC/HRMS using multiple ion detection mode(MID),which was a advanced and authority technique named US EPA1613 method.Results:The average concentration of 31 sea fishes was 2.38 pg/g wet weight,and the average Total Toxicity Equivalency Factor(TEQ) was 0.35 pg/g wet weight.The PCDD/Fs contamination level was different from sample to sample.A congener-specfic profile dominated by OCDD and 2,3,7,8-TCDF was found,and the main contributor of toxicity was 1,2,3,7,8-PeCDD、2,3,7,8-PeCDF.The evaluation dietary intake of PCDD/Fs from fish for local people was 0.63 pg WHO-TEQ/kg BW·day.Conclusion:The PCDD/Fs contamination level in some individual fishes exceeded the limit standards of European Commission,PCDD/Fs contmination status in animal originated food in China should be studied as soon as possible in order that limit standard can put forward to protect people's health.