[TAS method for the detection of methyl parathion (0.0-dimethyl-(p-nitrophenyl)-thiophosphoric acid ester) and various transformation products in organic materials].

A simplified TAS method was used to determine parathion-methyl (0.0-dimethyl-0-p-nitrophenyl phosphorothioate), methyl-paraoxon and p-nitrophenol in samples of animal origin and in foodstuffs. These substances were isolated by thermomicropartition in the TAS oven, with immediate uptake of the condensate on thin-layer plates. Identifications was done directly from the sample or from the residue of a crude extract. After partition by thin-layer chromatography, the compounds were rendered visible by coupling with suitable amines. By means of the TAS method it was possible to detect 2-4 ppm parathion-methyl and methyl-paraoxon, or 3-4 ppm p-nitrophenol directly from samples, or 0,05-0.10 ppm of the first two compounds and 0.1-0.5 ppm of p-nitrophenol in the residue of extracts.