Analysis of organochlorine pesticides using solid-phase microextraction

A solid-phase microextraction (SPME) procedure has been developed to successfully extract eighteen chlorine-containing pesticides from water. A fused-silica fiber coated with a non-polar polydimethylsiloxane stationary phase was used to extract the analytes from water samples over a concentration range of 0.001 to 100 ng/ml. Limits of detection at a ng/l level were achieved with GC and flame ionization detection, and improved to sub ng/l levels using GC-MS, or GC with electron-capture detection (ECD). The reproducibility of the measurements between fibers was found to be very good, with precision typically below 20% R.S.D. within a single fiber. Qualitative analysis was performed on river and lake samples from Southern Ontario. Samples from the Arctic region of Canada were analyzed quantitatively using a dual ECD system.