GC Determination of Trace Amount of Organophosphorous Pesticides in Aquaculture Water with Solid Phase Disk Extraction

GC with solid phase disk extraction was applied to the determination of 3 organophosphorous pesticides,i.e. roxion,methyl parathion and malathion in aquaculture water. The water sample was extracted by C18 solid phase disk,and eluted with acetone and dichloromethane. The analytes were separated on a SPB-608 capillary column and detected by NPD. Linear relationships between values of peak area and the mass concentration of 3 organophosphorous pesticides were kept in the same range of 0.02-1.0 μg·L-1,with detection limits (3S/N) in the range of 0.002 5-0.004 μg·L-1. The recovery rates measured by standard addition method were in the range of 93.0%-111%,with RSD (n=5) in the range of 0.13%-5.2%.