Extraction and gas-liquid chromatographic determination of hexachlorophene from several plant tissues

Conditions are described for extraction, cleanup, derivatization, detection, and quantitation of hexachlorophene (HCP) residues from several types of plant material. Wet plant tissue was homogenized and extracted with ethyl ether, dried, and methylated with excess diazomethane. Samples were precleaned by column chromatography on silica gel with benzene-petroleum ether (1 + 1), and then 1-10 microliter concentrated sample was chromatographed on a 6' column of 3% SE-30 on 80-100 mesh Gas-Chrom Q. The detection limit for the electron capture detector was less than 0.1 ng dimethoxyhexachlorophene and 1 ppb HCP in plant tissue. Recoveries (%) of 11-610 ppb HCP added to tissue averaged 94.3 for tomatoes, 86.4 for green peppers, 92.6 for cucumbers, 93.3 for green beans, 93.7 for peanut hay, and 91.6 for peanut shells.