摘要
为了解五氯硝基苯在土壤和西瓜中的消解动态及残留状况,研究了土壤和西瓜中五氯硝基苯的气相色谱检测方法,并在山东济南和浙江杭州进行了土壤和西瓜中五氯硝基苯残留状况和消解动态规律研究的田间试验。结果表明,在0.01～0.5 mg/kg的添加水平内,土壤和西瓜中五氯硝基苯的平均添加回收率为83.41%～93.17%,变异系数为3.37%～9.74%;土壤和西瓜中五氯硝基苯的最小检出量均为1.2×10^(-12)g,其中西瓜中五氯硝基苯的最低检出质量比为0.001mg/kg,土壤中为0.005 mg/kg。田间残留试验表明,五氯硝基苯在土壤和西瓜中的残留消解动态规律符合一级动力学反应模型,在土壤、全瓜和瓜瓤中的消解半衰期分别为4.13～6.08d、4.28～4.92d和3.67～4.10d。按推荐剂量和1.5倍推荐剂量在西瓜上各喷施质量分数为40%的多菌灵·五氯硝基苯可湿性粉剂1～2次,2次施药间隔为7d,距最后1次施药7d时,五氯硝基苯在瓜瓤中的最高残留量为0.005 8mg/kg,低于规定的果菜类蔬菜中五氯硝基苯的最大残留限量标准0.1mg/kg。
The present paper is aimed at introducing the findings of our dynamic research on the residue detection and degradation of pentachloronitrobenzene （PCNB） in watermelon and soil. In our research we have adopted an analytical method of gas chromatography so as to determine the pollution and degradation trends of the PCNB residue in watermelon and soil. The experimental results of our experiments and testing prove that the average recovery rate of PCNB is in a range of 83.41% -93.17% at the three spiking levels from 0.01 mg/kg to 0.50 mg/kg with their relative standard deviations of 3.37% - 9.74% in watermelon and soil. The detection limit turns to be 1.2 ×10^-12 g whereas the minimum mass ratio detected was 0.001 mg/kg in watermelon and 0.005 mg/kg in soil, respectively. A control and contrast trial experiment in Shandong provinee and Zhejiang pruvince was done with the finding results as follows： the degradation regulation of PCNB in watermelon and soil conformed to the first order ki- netics reaction model, with its haft-life being 4.13 -6.08 d, 3.67 - 4.92 d in the soil and the watermelon, respectively. Our research also shows that, when 40% carbendazim ＆ pentachloronitrobenzene wettable power was applied once and twice at an interval of 7 d with the dosages of 0.83 - 1.24 g/strain in the whole culture process, on the 7th day after the last application, the MRLs of PCNB would drop below 0. 1 mg/kg in the fruits and vegetables in accordance with the Chinese standard. Thus, it can be said that our experiments provide valuable scientific data for registration and secure application formulate of 40% carbendazim ＆ pentachloronitrobenzene wettable power, so as to protect agricultural environment and human health.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2010年第4期101-105,共5页
Journal of Safety and Environment
关键词
环境科学技术基础学科
五氯硝基苯
西瓜
土壤
消解动态
气相色谱法
basic disciplines of environmental science and technology
pentachloronitrobenzene
watermelon
soil
degradation dynamics
gas chromatography
