A volatile organophosphorus insecticide. It is of high acute toxicity but its rapid metabolism renders it safe under correct conditions of use. It is directly active without having to be metabolized first. SELECTED PROPERTIES Physical characteristics - When pure a colourless liquid, b.p. 35°C at 0.05 Torr, density 1.415 at 25°C. Corrosive to mild steel and other metals. Solubility - Water at 20°C, 0.9%, kerosine 2-3%. Miscible with aromatic hydrocarbon solvents, chlorinated hydrocarbon solvents and alcohols. Stability - Stable to heat, hydrolyses in aqueous solutions. The saturated aqueous solution is decomposed at the rate of 3% per day (half life 23 days). Decomposition occurs more rapidly in alkali and in strongly acid solutions. At pH 1 complete hydrolysis occurs within 50 minutes at room temperature. The vapour is rapidly hydrolysed in air. Compatible with most technical pesticides.