GC Determination of 16 Organochlorine Pesticides in Water with Headspace Solid Phase Microextraction

Water sample (8.00 mL) was placed in 20 mL headspace flask and saturated with 3 g of sodium chloride. The solution was extracted for 60 min at 70℃ at a vibration rate of 250 r·min^-1, using the extract fiber of poly (dimethylsiloxane)/divinylbenzene (PDMS/DVB). After extraction, the PDMS/DVB extract fiber was inserted into GC and desorbed for 4 min. The extract was separated by GC using HP-5 chromatographic column as stationary phase. Linear relationships between values of peak area and mass concentration of 16 organochlorine pesticides were found in definite ranges, with detection limits (3.143s) in the range of 0.001-0.005 μg·L^-1. Test for recovery was made by standard addition method, giving results in the range of 70.6%-132%, with RSDs (n=6) ranged from 3.7% to 30%. The preservation of organochlorine pesticides in water was studied by the above method.