乙撑硫脲在人参和土壤中残留分析与消解动态

通过田间试验和液相色谱分析技术研究了75%代森锰锌WP的杂质及代谢物乙撑硫脲在人参和土壤中残留分析与消解动态。试验结果表明:当75%代森锰锌WP的施药剂量为推荐剂量的2倍(6 250 g/hm2)时,其杂质及代谢物乙撑硫脲在人参和土壤中原始沉积量分别为0.025和0.032 mg/kg,半衰期分别为18.1和14.2 d。当使用75%代森锰锌WP施药1次,测得人参中乙撑硫脲残留量均低于欧洲规定的农药最高残留限量值(0.05mg/kg),按照推荐剂量3 125 g/hm2处理,建议我国乙撑硫脲在人参上的最大残留限量值可暂定为0.02～0.04 mg/kg,施药次数为1次。

Residue Analysis and Degradation Dynamics of Ethylenethiourea in Panax ginseng and Soil

Field trial and high performance liquid chromatography analysis were performed to study the residue and degradation dynamics of the impurity in Mancozeb(75% WP) and its metabolite ethylenethiourea in Panax ginseng and soil.Results of the field trial showed that,when the application dosage of Mancozeb(75% WP) was three times as much as the recommended dosage(6 250 g/hm2),the original deposition of ethylenethiourea in P.ginseng and soil were 0.025 and 0.032 mg/kg,and the half-life periods were 18.1 and 14.2 d,respectively.When the ginseng was sprayed with Mancozeb(75% WP) once,the ethylenethiourea residues in P.ginseng were all below the maximum residue limit of Europe(0.05 mg/kg).It is recommended that the maximum residue limits of ethylenethiourea in P.ginseng prayed once during the growth period according to the recommended dosage of Mancozeb(3 125 g/hm2) should be determined as 0.02-0.04 mg/kg temporarily.