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Laboratory Estimation of Net Trophic Transfer Efficiencies of PCB Congeners to Lake Trout (Salvelinus namaycush) from Its Prey
Published on: August 29, 2014
Congener-specific distribution of polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls in animal feed
Byung-Hoon Kim1, Jin-Suk Jeong, Yoon-Seok Chang
1School of Environmental Science and Engineering, Pohang University of Science and Technology, Korea.
Abstract:
Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) were extracted by accelerated solvent extraction from animal feed samples and analysed by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). In all of the feed samples analysed, the concentrations of PCDD/Fs and PCBs were below the existing tolerance limit of 5 pg I-TEQ g(-1) and 200 ng g(-1) fat, respectively. The mean concentrations of the total PCDDs, total PCDFs and total PCBs were 1.73-11.50 pg g(-1), 0.23-11.91 pg g(-1) and 60.00-234.40 pg g(-1) feed, respectively. Investigation of the correlations among the concentrations of PCDDs, PCDFs and PCBs showed that samples containing increased amounts of PCDFs also contained higher concentrations of PCDDs, with an average ratio of PCDF:PCDD of about 1.23:1 (r(2)=0.72, p<0.05). The correlation between the concentrations of PCDD/Fs and PCBs was positive but not significant.
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