On the Isolation and Identification of Organophosphorus Pesticide from Various Specimens of a Female Corpse and the Assay of Acetylcholinesterase Activity in the Blood

Recently, the authors have experienced the autopsy of a female victim who died of organophosphorus pesticide intoxication. Therefore, for the purpose of clarifying the dead cause, we carried out the separation and identification of organophosphorus pesticide from the specimens such as the stomach contents, cardiac blood and urine of this cadaver and further the measurement of acetylcholinesterase activity in the blood. The results were as follows. 1. Acetylcholinesterase activity in the serum and erythrocytes. The serum and erythrocytes were separated by centrifugation for 5 minutes at 3000rpm and subjected to the assay of acetylcholinesterase activity on the basis of Pilz's method. Acetylcholinesterase activities were 0.312μAq in the erythrocytes and 0.078μAq in the serum, respectively. These values abruptly lowered in comparison with those in the serum and erythrocytes of healthy human adults and the inhibition of acetylcholinesterase activity was clearly observed. 2. Separation and identification of organophosphorus pesticide Unknown organophosphorus pesticide was first extracted from the stomach contents, cardiac blood and urine with ethanol according to Stas-Ott's method and then the crude materials purified by use of both the silicagel column and thin-layer chromatographies. Subsequently the qualitative analysis of organophosphorua pesticide was undertaken by means of ρ-nitrophenol and Averell-Norris color reactiton, ultraviolet absorption spectrophotometry, infrared absorption spectrophotometry, thin-layer chromatography and gas chromatography. As a result, the organophosphorus pesticide extracted from various specimens of this cadaver was identified as malation.