GC Determination of 12 Pesticides in Drinking Water with Solid Phase Extraction

GC with solid-phase extraction was applied to the determination of 12 pesticides in drinking water. Water sample (250 mL) was extracted on C18 solid phase extraction column (SPE). The pesticides on SPE column were eluted with ethyl acetate (5 mL) and n-hexane (5 mL) successvely. Anhydrous Na2SO4 was used for dehydration. The analytes were separated on DB-5MS capillary column and detected by ECD. Linearity range of decamethrin was 0.05-0.5 mg·L-1, and all the other pesticides′ were found between of 0.01-0.1 mg·L-1. Detection limit of the method for decamethrin was 24.2 ng·L-1 and other pesticides′ were below 10 ng·L-1. Values of average recovery of 12 pesticides in water ranged from 70.0% to 110%, and RSD (n=6) were less than 10%.