Gardner A M, Abramovitch A
J Assoc Off Anal Chem. 1984 Nov-Dec;67(6):1082-5.
A procedure was developed to determine chlorinated methylthiobenzenes and their respective sulfur oxidation products in fish. Perch samples fortified at the 0.1 ppm level with 2,4,5-trichloromethylthiobenzene, pentachloromethylthiobenzene, and their sulfoxides and sulfones were extracted and cleaned up using an adaptation of the official AOAC method for multiple residues of organochlorine pesticides. The Florisil column cleanup was modified; 200 mL 6% petroleum etherethyl ether eluted the methylthiobenzenes, 200 mL 50% PE-EE eluted the sulfones, and 200 mL EE eluted the sulfoxides. Recoveries determined by electron capture (ECD) gas chromatography (GC) were 75-101% for the methylthiobenzenes and their sulfones and 63-93% for the sulfoxides. Co-extracted materials in the Florisil eluates that interfered with the ECD/GC quantitation were removed by partitioning the sulfoxides and sulfones into sulfuric acid and by thin layer chromatography on silica gel, using methylene chloride-hexane (50 + 50) as the developing solvent. Seven fish samples containing residues of chlorinated benzenes or polychlorinated biphenyls (PCBs) were examined for chlorinated methylthiobenzenes, methylthio-PCBs, and their oxidation products by matching GC retention times obtained with the EC detector and a flame photometric detector operated in the sulfur mode. These analytes were not found in the fish samples above a detection level equivalent to 0.02 ppm 2,4,5-trichloromethylthiobenzene.
已开发出一种用于测定鱼类中氯代甲基硫苯及其各自硫氧化产物的方法。用2,4,5 - 三氯甲基硫苯、五氯甲基硫苯及其亚砜和砜在0.1 ppm水平对鲈鱼样品进行强化，然后采用美国官方分析化学家协会（AOAC）测定有机氯农药多残留的方法进行提取和净化。对弗罗里硅土柱净化方法进行了改进；用200 mL 6%石油醚 - 乙醚洗脱甲基硫苯，200 mL 50%石油醚 - 乙醚洗脱砜，200 mL乙醚洗脱亚砜。通过电子捕获（ECD）气相色谱（GC）测定的回收率，甲基硫苯及其砜为75 - 101%，亚砜为63 - 93%。通过将亚砜和砜分配到硫酸中以及在硅胶上用二氯甲烷 - 己烷（50 + 50）作为展开溶剂进行薄层色谱，去除了弗罗里硅土洗脱液中干扰ECD/GC定量的共提取物。通过匹配用电子捕获检测器和在硫模式下操作的火焰光度检测器获得的GC保留时间，对七个含有氯苯或多氯联苯（PCBs）残留的鱼类样品进行了氯代甲基硫苯、甲硫基多氯联苯及其氧化产物的检测。在鱼类样品中未发现这些分析物的含量超过相当于0.02 ppm 2,4,5 - 三氯甲基硫苯的检测水平。
