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Determination of PCB Residues in Vegetables by GC-MS

This paper examines a method for the simultaneous detection of 12 different dioxin-like polychlorinated biphenyl (PCB) residues in vegetables. A qualitative and quantitative determination of PCB residues in vegetables was undertaken by a combination of high-speed freezing centrifugation, solid phase extraction, purification, concentration, and GC- MS and GC-ECD. From this combination of methods, 12 different PCBs were detected in vegetables over a linear concentration range of 0.001 to 2 µ g/L (ppb), with detection limits ranging from 0.4ppb to 0.5 ppb, a linear correlation coefficient of 0.99, recoveries ranging from 96.25%-117.5%, and a relative standard deviation ≤ 21%(RSD) .