DETERMINATION OF TOXAPHENE IN SOIL BY ELECTRON-CAPTURE NEGATIVE-ION MASS-SPECTROMETRY AND CAPILLARY COLUMN GAS-CHROMATOGRAPHY

Although toxaphene is now limited in use, interest in its analysis continues because of its persistence and widespread atmospheric transport in the environment and its presence in many dump-sites all over the world. Top soil samples collected from a dump site were analyzed for toxaphene residues. Analyses were performed by wall-coated open tubular column gas chromatography in tandem with electron-capture negative-ion mass spectrometry. Since the concentrations of toxaphene residues were at mg/kg levels, the application of a mass spectrometer as a substance-selective detector has been applied. Advantages of this mode of real-time acquisition in continuous repetitive scanning of mass spectra has significant advantages in comparison to the selected-ion monitoring technique. An average R.S.D. of 10% and recoveries of 90 to 109% were obtained. Levels down to 50 mu g/kg are obtainable.