Determination of methylthio and methylsulphone polychlorinated biphenyls in tissues of patients with 'yusho'.

The liver, lung and mesenteric adipose tissue of three patients with 'yusho', polychlorinated biphenyl (PCB) poisoning, and two control persons were analysed for methylthio and methylsulphone metabolites of PCBs by gas chromatography with electron capture detection, gas chromatography-mass spectrometry and mass fragmentography. The tissues were shown to contain two congeners of methylthio PCBs with four chlorine atoms, and 16 congeners of methylsulphone PCBs with three, four, five or six chlorine atoms. The concentrations of methylthio PCBs in the liver, lung and adipose tissue of the yusho patients were 0.1-0.5, 0.2-1.4 and 0.5-1.0 micrograms/kg, respectively, and those of methylsulphone PCBs were 0.3-0.7, 1.0-2.5 and 0.7-1.0 micrograms/kg, respectively. The concentration ratios of methylthio and methylsulphone PCBs to unchanged PCBs were 1-2% in the liver, 4-8% in the lung and 0.1-0.2% in the adipose tissue for yusho patients, indicating that these metabolites accumulate slightly more in the lung and liver than in the adipose tissue, relative to PCBs. The tissue levels of the PCB metabolites in control persons were about one tenth of those in yusho patients.