The use of experimental design for optimisation of QuEChERS extraction of commonly used pesticides in Egyptian soil and drainage water and their determination by GC/MS

In this study, a Quick, Easy, Cheap, Effective, Rugged and Safe method (QuEChERS) method was optimised to extract 30 pesticides which are the most used in Egypt in soil and drainage water. Optimisation was performed by Experimental Design expert 7.1 to get better recoveries. The procedure combined with a developed GC-MS for determination of these pesticides. Total analysis time was 36 min with 1 ml injection volume. The limit of quantification (LOQ) was ranged between 4.59 ng/ml, and 15.91 ng/ml for all pesticides. Most standard deviations were in the range between 0.41 and 1.41 indicating satisfactory accuracy. The validated method was applied to Egyptian soil and drainage water samples brought from different places in Damietta city. Dimethoate, β-Endosulfan, DDD, Malathion, Vinclozolin, DDT, Endrin, Cyprodinil, Primiphos ethyl, Tetradifon, Parathion ethyl and Diazinon were detected and quantified. So risk assessment on human health should be considered especially for those pesticides.