To the Editor.— Reports of possible harmful effects of pesticide residues in lanolin in Australia 1 recently prompted us to question the pesticide content of lanolin used as both an absorbent ointment and an ointment base. The absorbent ointment (anhydrous lanolin) is frequently used to treat sore, cracked nipples in breast-feeding mothers. In addition, the ointment base is used in pharmaceuticals and cosmetics. Two lots (numbers 5922 and 6441) of United States Pharmacopeia anhydrous lanolin from a single manufacturer were analyzed by the Division of Colors and Cosmetics, Food and Drug Administration (FDA). The analysis (Table) by the FDA indicated that pesticide contamination varied significantly between lots and that dimpylate (Diazinon), DDE (a metabolite of chlorophenothane [DDT]), lindane (benzene hexachloride [BHC], gamma), and alpha- and beta-BHC (isomers of hexachlorocyclohexane) were found in one or both samples (J. A. Wenninger, written communication, March 1988). The two additional lanolin lots (numbers 5631