Abstract:

This study had been carried out to investigate the residue behavior and environmental safety of 40% emamectin benzoate and chlorpyrifos EW in rice and paddy. The residues of emamectin benzoate and chlorpyrifos in samples were determined by HPLC-FLD and GC-ECD, respectively. And the field trials were conducted to reveal the dissipation and terminal residue of emamectin benzoate and chlorpyrifos in rice and paddy. The results showed that emamectin benzoate and chlorpyrifos dissipated rapidly in paddy water, soil and rice straw, and the half-lives of emamectin benzoate were 17.55, 35.55, 19.10 h, the half- lives of chlorpyrifos were 0.90-1.36 days, 3.02-5.30 days and 4.43-5.82 days, respectively. when 40% emamectin benzoate and chlorpyrifos EW was applied twice at recommended dosage in rice field, the final residues of emamectin benzoate were not detected in the rice that harvested more than 21 days after the last application, and the final residues of chlorpyrifos in the rice were below the maximum residue limit (MRL) 0.1 mg/kg of rice in China. So the rice harvested at this time was safe for human consumption.