Sumithion與 Parathion 遺毒消失快慢之比較

Abstract

Sumithion遺毒之分解較parathion為速，惟其遺毒之持續時間與用量之多寡關係甚大。若以含藥量1 ppm為遺毒安全基準，自第1表看出，在水稻莖葉中，以每公頃有效成份使用量750 gm（相當乳劑使用量1.5 kg）之低用量處理組，sumithion於處理後4天，其室內盆栽作物及田間供試作物上之遺毒含量皆不超過1 ppm，已符合本試驗之安全標準，而達安全程度。至Parathion於處理後7天，方能達到同一安全標準。關於高用量（每公頃有效成份2.25 kg）處理組，該二種藥劑於施藥後16天，尚皆不能達到絕對安全之程度。 自第2表看出，在稻穀中，於本試驗之施藥狀況下，sumithion乳劑，高濃度（1:1000倍），高用量（每公頃有效成份2.25 kg)，於慣用之採收前15天施藥，其在稻穀中之遺毒含量可保絕對安全。 The stabilities of sumithion [ο,ο-Dimethyl-ο-(3-methyl-4-nitrophenyl) phosphoro-thioate] and ethyl parathion residues on growing rice crops and green-stem cabbage were compared in this study. The experiments with 50% of the emulsion concen-trations of the chemicals were carried out in August to December 1962 and March to April, 1963. Residues were extracted into purified benzene, and filtered through filter tubes (dia. 4 cm × height 5 cm) containing 5 grams of Norit-A. The Averell-Norris (1948) colorimetric method and the dry film method with three-day old house flies were used for chemical analysis and bioassay respectively.