Residues of carbofuran and its two carbamate metabolites in field-treated rutabaga.

Carbofuran was applied over seeded rutabaga cv. York and residues (corrected for recovery) of carbofuran, 3-hydroxy- and 3-ketocarbofuran in the harvested roots averaged 0.15, 0.23 and 0.07 ppm in peel and 0.09, 0.14 and 0.05 ppm in pulp, respectively. Samples were extracted by hot acid digestion, partitioned in methylene chloride and cleaned up on Florisil. The 3-hydroxy-carbofuran was ethoxylated and the compounds were converted into their dinitrophenyl ethers and analysed by electron capture gas chromatography using 3% OV-3 column.