氯化苦在土壤中的消解动态和残留量检测研究

[目的]研究氯化苦在土壤上的残留分析方法及在土壤中的消解动态和最终残留量。[方法]采用气相色谱法测定氯化苦在土壤中的残留，用石油醚对土壤样品进行超声波提取，毛细管柱色谱分离，电子捕获检测器进行测定，进行了3种添加浓度的回收率试验并进行实际样品检测。[结果]氯化苦的的最低检出限（LOD）为0.008mg／kg，土壤中最低检出浓度（LOQ）为0.020mg／kg，回收率89.5％—111.1％，变异系数为3.6％—7.2％，均在农药残留测定所允许的范围内。同时在0.008—2.000mg／L浓度范围内峰面积值与氯化苦浓度线性关系良好，且线性范围较宽，适合测定土壤中不同浓度水平的氯化苦。氯化苦的消解很快，在土壤中的半衰期为5.5d。[结论]该分析方法操作简单、快速，定量准确，可有效地测定土壤中氯化苦含量。

Study on Degradation Dynamics and Residues Detection of Chloropicrin in Soil

[Objective] The purpose was to study the analysis methods of Chloropicrin residue in soil and its digestion dynamics in soil and the final residue.[Method] Chloropicrin residues in soil were detected with gas chromatography.The sample were extracted with petroleum ether for ultrasonic extraction,separated with capillary column chromatography and determined with electron capture detector.The recovery test by adding 3 kinds of concn.was carried out and the actual samples were also detected.[Result] The minimum detection limit(LOD) of Chloropicrin was 0.008 mg/kg,the minimum detectable concentration in soil(LOQ) was 0.020 mg/kg,the recovery rate was 89.5%-111.1%,and coefficient of variation was 3.6%-7.2%,which were all in the allowed range of pesticide residue determination.At the same time,in 0.008-2.000 mg/L concn.range,there was a good linear relationship between the peak area value and the concentration of chloropicrin and the wide linear range was suitable for determination on Chloropicrin at different level in soil.Chloropicrin digested soon and its half-life in soil was 5.5 d.[Conclusion] This analysis method had characters of simple operation,rapid in velocity and accurate in quantification,which could be effective to measure the content of Chloropicrin in soil.