GC Determination of 21 Organochlorine and 4 Organophosphorus Pesticides in Soil

GC was applied to the determination of 21 organochlorine and 4 organophosphorus pesticides (OCP′s and OPP′s) in soil. The sample (10 g) was extracted for 7 h with 200 mL of a mixture of acetone and nhexane (1+1) at 65 ℃ by soxhlet extraction. The extract was evaporated to ca. 2 mL and purified on SPE column. The column was eluted thrice with acetonnhexane (1+1) mixture, 2 mL of which were used in each elution. The eluate was evaporated to 1 mL and used for GC analysis. Separation on CLPⅡcapillary column and detection by ECD were used for determination of OCP′s, and separation on 1701 capillary column and detection by FPD were used for determination of OPP′s. Linear relationships between values of peak area and mass concentration of the 21 organochlorines and 4 organophosphoruses were kept in definite ranges. Detection limits (3S/N) found were ranged from 0.14 to 0.38 μg·kg-1. Values of recovery found by standard addition method were in the range of 68.0%-125%, with values of RSD′s (n=10) the range of 2.8%-5.9%.