茶园用药安全性指标的设计

根据20余种化学农药在茶树上降解动态的研究结果,提出了茶园用药安全性指标设计的概念。从农药被喷施在茶树上到随茶汤进入人体整个过程,在影响人体安全的因素中,作者选用了农药的5个物理、化学和生物学参数作为选择农药在茶园中适用性的安全性指标,也可供有针对性地合成农药结构设计时参考。上述5项指标中有4项属农药常用参数。这5项指标是:①在茶树鲜叶上的半衰期;③蒸气压;⑧水中溶解度;④允许每日摄入量(ADI);⑤大白鼠口服急性 LD_(50)。每项指标分为4级,其累计值即为该农药的安全性评价值。累计值低于或等于10属

Design of Safety Parameters for Selecting the Pesticide Used in the Tea Garden

A model of safety evaluation for selecting the pesticide used in the tea garden wassuggested by the author according to the experimental results of the degradative dynamicsof more than 20 pesticides on the tea bush.Among the main factors influencing thedegradation of pesticides and the safety of human from the pesticide was applied onthe tea bush to the pesticide residue entered the human body with the tea infusion,5 physical,chemical and biological parameters of pesticides were selected as thesafety indexes by the author in the purpose of selecting the pesticide suitable in the teagarden.It also would be useful in the structural design of synthesizing the pesticidepurposefully.It comprises the following 5 selective parameters and each of which issub-divided into 4 classes.(1)Half-life(HL_(50))on fresh tea leaves:1st class<0.6days;2nd class 0.61-1.5 days;3rd(?)class 1.51-3.0 days;4th class>3.0 days.(2)Vapour pressure of pesticide(mm Hg,20-25℃):1st class>1×10~(-5);2nd class1×10~(-5)—1x10~(-6);3rd class 1x10~(-6)—1x10~(-7);4th class<1×10~(-7).(3)Watersolubility of pesticide(ppm,20-25℃):1st class<1;2nd class 1-100;3rd class101-200;4th class>200.(4)ADI value(Acceptable Daily Intake)of pesticide(mg/kg.day):1st class>0.01;2nd class 0.005-0.01;3rd class 0.001-0.0049;4th class<0.001.(5)Oral LD_(50)of acute toxicity in rats(mg/kg):1st class>500;2nd class 101-500;3rd class 31-100;4th class<30.The evaluation ofthe safety of pesticides is based upon the cumulative value of the above 5 parameters.It is showed that the lower the cumulative values,the safer the pesticide.If thecumulative value of a pesticide is over 12,it can not be used in the tea garden.