RAPID-DETERMINATION OF DDT AND RELATED COMPOUNDS IN SOILS VIA CARBON SKELETON GAS CHROMATOGRAPHY-MASS SPECTROMETRY

The levels of DDT and related compounds in soil samples from an apple orchard have been determined. Extraction of residues was achieved by cyclic team extraction and by conventional solvent extraction methods allowing comparison of the two methods. Determination of the organochlorine residues present in the extracts was performed by gas-liquid chromatography-electron-capture detection and by carbon skeleton gas chromatography-mass spectrometry. Excellent agreement between the two determination techniques was achieved. Prior to application of p,p′-DDT, a value of approximately 0.4 ppm was obtained for ΣDDT in the soil. The major component of this total was DDE. After spraying the apple trees with technical grade p,p′-DDT, ΣDDT for the soil rose to 0.6 ppm. This increase was due to translocation of p,p′-DDT from the trees,. © 1979.