U. Kiigemagi, Lucia R. Durand, M. Becerra
Mar 1, 1990
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0
Influential Citations
3
Citations
Journal
Journal of Agricultural and Food Chemistry
Abstract
An analytical method developed for the determination of ethoprop in fresh and spent mint hay included initial extraction with hexane in the presence of anhydrous sodium sulfate, cleanup using charcoal and deactivated Florisil, and quantitation by phosphorus-specific flame photometric gas chromatography. Mint oil samples were introduced directly onto the deactivated Florisil columns, and the ethoprop concentration in the eluate was again determined by gas chromatography. The method is sensitive to 0.002 ppm in mint hay and to 0.05 ppm in mint oil. Recoveries averaged 90% for samples fortified immediately before analysis and 89% for samples stored 4-58 weeks. Residue data from nine locations collected over three seasons showed traces of ethoprop in almost all fresh and spent hay samples ranging from <0.002 to 3.36 ppm. Ethoprop residues in mint oil ranged from <0.05 to 114 ppm, the highest residue being in spearmint oil treated at 13.2 kg of AI/ha 90 days before harvest.