四聚乙醛在烟草和土壤中的残留检测和消解动态.pdf

2006, 8( 4) : 344348 Chinese Journal ofP esticide Science 研究论文 * 张雪燕 , 代雪芳 ( , 650205) :建立了烟草和土壤中四聚乙醛残留量的气相色谱分析方法样品中残留的四聚乙醛用二 氯甲 提取, 中性氧化铝与活性炭混合柱净化,偏重亚硫酸钠溶液除去游离醛, 所得的四聚乙醛经 盐酸解聚成乙醛, 乙醛与 2, 4- 二硝基苯肼进行衍生化反应, 经硅胶柱净化, CNPD 测定其衍生 物方法的最小检出量为 0. 04 ng, 最低检出浓度为 0. 02~ 0. 10 mg/kg; 3 个添加水平的平均回收 率为 86% ~ 100%, 相对标准偏差(RSD )均小于 15% (n = 5)四聚乙醛在烟草及土壤中的残留试 验结果表明: 烟草植株对四聚乙醛的吸收在施药后4~ 5 d达到高峰, 之后缓慢下降,到 21d已接近 最低检出浓度 0. 04 mg/kg; 其在土壤中的半衰期约为 4 d; 在推荐使用剂量下, 四聚乙醛在干烟叶 中的残留量低于最低检出浓度 0. 10m g/kg, 不会对烟草造成残留污染 : 四聚乙醛; 烟草; 土壤;残留 : S481. 8; X592 : A : 2006 Degradation and Determ ination of the Residue ofM etaldehyde in Tobacco and Soil * ZHAN Xueyan , DA IXuefang ( Institute ofAgroEnvironmentalResources, Yunnan Academ y ofAgricultural Science, Kunm ing 650205, China) Abstract: A m ethod for determ ination of metaldehyde residues in tobacco was developed. M etaldehyde residueswere extracted from tobacco w ith dichlorom ethane and cleaned up w ith them ixture column of alum inum oxideactivated carbon. Interfering aldehydes w ere rem oved w ith sodium m etabisulphite solution. M etaldehyde was depolymerized w ith hydrochloric acid to acetaldehyde, which w as reacted w ith 2, 4dinitrophenylhydrazine. The derivative acetaldehyde 2, 4dinitrophenylhydrazone was cleaned up on silica gel colum n and determ ined by CNPD. The lmi it of detection of metaldehyde was 0. 04 ng. The lmi itof quantification of themethod for pesticide in tobacco and soilw as0. 02 to 0. 10mg/kg. The recoveries from 3 sam ples fortifiedw ithm e