Department of Applied Chemistry, College of Science, China Agricultural University, 2 Yuanmingyuanxilu, Haidian District, Beijing 100193, China.
Institute of Pesticide and Environmental Toxicology, Guangxi University, 100 daxuedonglu, Nanning 530005, China.
Int J Environ Res Public Health. 2014 May 16;11(5):5372-81. doi: 10.3390/ijerph110505372.
A modified quick, easy, cheap, effective, rugged (QuEChERS) method with multi-walled carbon nanotubes (MWCNTs) as reversed-dispersive solid phase extraction (r-DSPE) material was applied to the analysis of pirimiphos-methyl and deltamethrin residues in stored rice. Two dustable powder (DP) formulations (2% pirimiphos-methyl and deltamethrin DP; 5% pirimiphos-methyl DP) were applied in simulated storehouse trials in the lab. The residues and dissipation of the two pesticides in stored rice were investigated. Slow dissipation of both pesticides was observed in stored rice. The half-lives of pirimiphos-methyl were 23.9-28.9 days, and those of deltamethrin were 23.9-24.8 days. Residues of pirimiphos-methyl from application rates of 4.5-6.75 a.i. mg/kg (active ingredient milligram per kilogram) and 10-15 a.i. mg/kg were 1.6-3.8 mg/kg and 3.0-4.5 mg/kg at 60 days Pre-harvest Interval (PHI). Residues of deltamethrin from an application rate of 0.5-0.75 a.i. mg/kg were 0.13-0.14 mg/kg at 60 days PHI. Both pesticides residues were below the Maximum Residue Limits (MRLs) established by the Codex Alimentarius Commission (CAC). Therefore, at the recommended dosages they are safe for use on stored rice.
采用改良的快速、简便、廉价、有效、耐用（QuEChERS）方法，以多壁碳纳米管（MWCNTs）作为反分散固相萃取（r-DSPE）材料，用于分析储存在稻谷中的甲基嘧啶磷和氯菊酯残留。两种可湿性粉剂（DP）制剂（2%甲基嘧啶磷和氯菊酯 DP；5%甲基嘧啶磷 DP）在实验室模拟仓库试验中进行了应用。研究了两种农药在储存在稻谷中的残留和消解情况。在储存在稻谷中，两种农药的消解都很慢。甲基嘧啶磷的半衰期为 23.9-28.9 天，氯菊酯的半衰期为 23.9-24.8 天。在施用量为 4.5-6.75 a.i. mg/kg（有效成分毫克/千克）和 10-15 a.i. mg/kg 时，60 天收获前间隔期（PHI）的残留量为 1.6-3.8 mg/kg 和 3.0-4.5 mg/kg。在 0.5-0.75 a.i. mg/kg 的施用量下，氯菊酯的残留量在 60 天 PHI 时为 0.13-0.14 mg/kg。两种农药的残留量均低于食品法典委员会（CAC）规定的最大残留限量（MRLs）。因此，在推荐剂量下，它们在储存在稻谷中使用是安全的。
