摘要
采用气相色谱(GC-NPD)测定了马拉硫磷在柑桔及土壤中的消解动态和最终残留。样品用丙酮提取,经液液萃取净化,气相色谱氮磷检测器检测,外标法定量。结果表明:马拉硫磷在桔皮、桔肉、柑桔全果(果皮、果肉)和土壤中的添加回收率在0.05～1mg/kg水平时分别为90.1%～97.1%、85.0%～89.0%、85.3%～90.5%和85.8%～90.0%;相对标准偏差分别为2.06%～6.79%、4.00%～7.57%、2.47%～4.74和4.94%～7.06%。马拉硫磷的最小检出量为1.79×10-11g,在土壤和柑桔全果中的最低检出浓度分别为0.013和0.009mg/kg。马拉硫磷在柑桔全果和土壤中的半衰期分别为7.86～12.16d和1.0～2.0d;施药浓度为推荐剂量,最多3次,最后一次施药距采收间隔期为20d时,在收获的柑桔桔皮中马拉硫磷的残留量为0.026～0.117mg/kg,桔肉中的残留量低于最低检测浓度。
Gas chromatography equipped with a nitrogen-phosphorus detector （GC-NPD） was used in the field residue decline study and final residues of malathion in citrus and soil. Samples were extracted with acetone and the extracts were cleaned up by liquid-liquid extraction, followed by determination using GC. The recovery was from 90.1% to 97.1% for the citrus＇ pericarp, 85.0% - 89.0% for pulp, 85.3%- 90. 5 for the citrus and 85.8% - 90.0% for soil with coefficients of variation of 2.06% - 6.79% ,4.00%-7.57% ,2.47% - 4.74 and 4.94% - 7.06% respectively. The limit of detection was 1.79 × 10^-11 g. The limit of quantification was 0.013 mg/kg for soil, 0. 009 mg/kg for citrus, pericarp and pulp. The half-life of malathion was 7.86 - 12.16 days in citrus and 1.0 - 2.0 days in soil. When sprayed for 3 successive times at application rate of 0.30 g/L, at interval time of 20 d after the last application, the final residues of malathion in citrus＇ pericarp were between 0. 026 mg/kg to 0.117 mg/kg, and the final residues of malathion in citrus＇pulp were lower than 0. 009 mg/kg.
出处
《农药学学报》
CAS
CSCD
2008年第4期487-490,共4页
Chinese Journal of Pesticide Science
基金
农业部农药残留基金项目(NCR06076)
关键词
残留动态
马拉硫磷
柑桔
土壤
field residue decline study
malathion
citrus
soil
