GC-NPD and GC-MS Analysis of Preserved Tissue of Bhopal Gas Disaster: Evidence of Methyl Carbamylation in Post-Mortem Blood

Twenty-five preserved autopsy blood samples of Bhopal toxic gas exposed victims were analysed by gas chromatography (GC) coupled with either Nitrogen-Phosphorous detector (NPD) or mass spectrometer (MS) for the presence of methyl carbamyl valine in terms of valine methyl hydantoin (VMH). 84% of these samples showed a positive test for VMH on GC-NPD and the identity of the peaks were further confirmed on GC-MS. The concentration of VMH in the gas-affected positive blood samples ranged from 2.56 to 51.28 nanomoles. These results indicate entry of methyl isocyanate (MIC), one of the constituents of the toxic cloud caused by the disaster, into the blood stream of victims who had inhaled gas.