Acephate in biological fluids of two autopsy cases after ingestion of the chemical

Two autopsy cases, where the individuals were suspected of having ingested acephate, an organophosphorous insecticide, are reported. Acephate and its active metabolite, methamidophos (MP), were analyzed in the biological fluids by GC/MS, using the salting out method with liquid-liquid extraction columns. The first case was that of a 70-year-old man whose blood acephate was 149 microg/mL, and MP was 3.0 microg/mL. Serum pseudocholinesterase (ChE) activity was inhibited. No remarkable finding of injury or disease was determined as the cause of his death, but acute poisoning by acephate was mostly suspected. The second case was that of a 60-year-old man. A deep gash in the left neck injured the left common carotid artery in addition to the severely ischemic state of the primary organs. His blood acephate was 46 microg/mL, and MP was not detected. ChE activity was in the normal range. Hemorrhage was mainly suspected as the cause of his death. The concentrations of acephate and MP in human blood after oral ingestion are first reported here, and the acute toxic level of acephate is discussed.