洗涤方法对有机磷农药残留的影响

Effects of different washing methods on pesticide organophosphorus residues

目的比较不同洗涤方法对果蔬表面有机磷农药去除效果的影响.方法利用可食用的无毒物质洗米水、面粉水、小苏打和食用碱4种洗涤溶液,对残留有机磷类农药(以氧化乐果为例)的蔬菜样品(白菜)进行清洗,经萃取、浓缩后,用磷钼蓝比色法进行测定.结果面粉水的清洗效果最好,通过对面粉水清洗效果进行单因素实验和正交实验,得出最佳清洗效果条件为面粉水浓度为3.5 g/500 mL、浸泡时间为17 min、浸泡温度为32℃,农药去除率达到83%.氧化乐果在为0.8~32.0μg/mL范围内线性范围良好,线性方程为Y=0.011X?0.005,相关系数为0.9955,检出限为0.8μg/mL.结论用面粉水对果蔬进行清洗,能够有效减少农药残留,此法简单、便捷、价廉,适合在日常生活中使用.

Objective To compare the effects of different washing methods for removing of organophos-phorus pesticides residual from the vegetable samples. Methods Four non-toxic substances (rice washing water, flour water, baking soda and dietary alkali) were used for the removing of organophosphorus pesticides residual (omethoate was taken for instance) from the vegetable samples (cabbage), then detected through phosphor molydate blue after extraction and concentration. Results It was showed the least residual quantity was using flour water. Using single factor experiment and orthogonal experiment, the conditions of best clean-ing effect were flour water concentration for 3.5 g per 500 mL water, soaking time for 17 min, soaking tem-perature for 32 ℃, and the pesticide removal rate reached to 83%. A good linear range was obtained between 0.8~32.0μg/mL, and the linear equation was Y=0.011X-0.005 with correlation coefficient of 0.9955, the limit of detection was 0.8μg/mL. Conclusion It is effective to reduce pesticide residues on the fruits and vegeta-bles by using flour water, and the method is simple, convenient and cheap, and suitable for use in daily life.