DETERMINATION OF TOXAPHENE IN SOIL BY ELECTRON-CAPTURE NEGATIVE-ION MASS-SPECTROMETRY AFTER FRACTIONATION BY HIGH-PERFORMANCE GEL-PERMEATION CHROMATOGRAPHY

Toxaphene is extracted from soil by standard procedures using Soxhlet or sonication methods. The extract is fractionated by high-performance gel permeation chromatography (HPGPC), which separates toxaphene from the bulk of co-extractives including polychlorinated biphenyls. This HPGPC fractionation has broad application to many problems of environmental analysis. A solid-phase extraction cleanup with silica gel further removes any polar components present in the collected fraction. Determination of toxaphene is accomplished by electron-capture negative ion mass spectrometry (ECNI-MS) after introduction by capillary gas chromatography. Levels down to 100 mug/kg in soil are obtainable. Brief mention is made of high-resolution ECNI-MS carried out at a resolution of 10 000.