An improved method was developed for the determination of dieldrin in various kinds of wool fabrics. Dieldrin was extracted under reflux with acetone-methanol (1 : 1), purified by Florisil column chromatography, and determined by gas chromatography with 63Ni-ECD. From wool fabrics processed in the laboratory with a moth-proofing preparation, Dielmoth XC-E 3·H/C, dieldrin was recovered in 91-94% yield by this method. Dieldrin content in 72 wool products analysed were as follows : 50-183μg/g in doeskin A and B, tuxedo cloth, muslin A, and blanket A ; 1.64-8.10μg/g in doeskin C and D, muslin B and C, babies'socks and men's socks ; 3.3-23.0μg/g in regenerated wool A-H ; 0.02-0.32μg/g in washed wool, wool tops, worsted yarn, and 49 other products. These data show that, though in a few cases, dieldrin is still being used as a moth-proofing agent for wool fabrics.
