摘要
用气相色谱法研究了辛硫磷的不同加工制剂、不同用药量、不同后处理方法及在不同谷物上的残留量。结果表明,在用量相同,后处理方法一致的情况下,辛硫磷在谷物上的残留量是乳油>粉剂>粒剂。谷物上辛硫磷的残留量与原始用药量呈正相关。过筛,水洗都能除去谷物上部分辛硫磷的残留量,但制剂不同去除率有明显差异。日光晒能迅速除去辛硫磷在谷物上的残留量。表皮结构光滑的大豆,绿豆等辛硫磷的残留量低,而小麦、大麦、大米在相同情况下,残留量就高一些。但2.5%辛硫磷微粒剂在正常用量下(以干谷物计有效成分为2ppm)谷物经过筛、水洗后都不会超过允许残留限量(0.05ppm)。
Gc-6A equipped with FPD detector was used to measure the resi- dues of phoxim of different formulations,dosages and treatments in the storage grains.The results show that the residues of phoxim in the storage grains are 50% Ec>2.5% Dust>2.5% G;the residues are increased with doses,and are di- minished with sieving,washing or sunning。The residues of phoxim in beans are less than wheat and rice.If 2ppm (a.i.) of 2.5% phoxim(MG) is used once, and the residues of Phoxim in grains is less than 0.05ppm.
