Key Laboratory of Pesticide Chemistry and Application, Ministry of Agriculture, Dep. of Pesticide, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
J Environ Qual. 2010 Apr 13;39(3):917-22. doi: 10.2134/jeq2009.0342. Print 2010 May-Jun.
Chloropicrin (CP) is highly volatile and may pose strong exposure risks for humans and the environment. A gelatin capsule formulation was developed to reduce atmospheric CP emissions and to improve application safety. The objective of this study was to determine the distribution, atmospheric emissions, and soil residual of CP after application in gelatin capsules to soil columns. Two treatments were studied: (i) CP liquid injection with polyethylene film and (ii) CP gelatin capsules with polyethylene film. For the CP liquid injection treatment, the concentration of CP peaked (120.7 microg cm(-3)) at the 20-cm depth 1 h after fumigant injection and decreased with time; at other depths, the CP concentration increased initially and decreased after a typical diffusion-dispersion process. For the gelatin capsule treatment, concentrations of CP at 20 cm depth increased slowly and peaked at 30.04 microg cm(-3) 264 h after application, indicating a slow CP release through the gelatin capsule shells. The results indicate that a rapid breakdown of gelatin capsules occurred between 11 and 12 d after application. The application of CP gelatin capsules reduced total CP emission by approximately 3 times compared with liquid injection with film cover. Similar residual soil CP was found between the liquid injection and the two gelatin capsule treatments. Chloropicrin gelatin capsules could be a promising new technology for reducing environmental emissions and potential human exposure.
氯化苦（CP）挥发性很强，对人类和环境可能构成很强的暴露风险。为此开发了明胶胶囊制剂，以减少 CP 的大气排放并提高应用安全性。本研究的目的是确定 CP 施用于土壤柱的明胶胶囊后在土壤中的分布、大气排放和残留情况。研究了两种处理方法：（i） CP 液体注射并用聚乙烯薄膜覆盖，以及（ii） CP 明胶胶囊并用聚乙烯薄膜覆盖。对于 CP 液体注射处理，施药后 1 小时 CP 的浓度在 20 厘米深度达到峰值（120.7 µg cm（-3）），并随时间降低；在其他深度，CP 浓度最初增加，然后经过典型的扩散-弥散过程降低。对于明胶胶囊处理，20 厘米深度的 CP 浓度缓慢增加，在施药后 264 小时达到 30.04 µg cm（-3）的峰值，表明 CP 通过明胶胶囊外壳缓慢释放。结果表明，施药后 11-12 天胶囊迅速破裂。与薄膜覆盖的 CP 液体注射相比，CP 明胶胶囊的应用将总 CP 排放量减少了约 3 倍。液体注射和两种明胶胶囊处理之间发现了相似的土壤 CP 残留。CP 明胶胶囊可能是减少环境排放和潜在人体暴露的一种有前途的新技术。
