Lack of oestrogenic effects of food preservatives (parabens) in uterotrophic assays

The oestrogenic activity of the parabens, methyl-, ethyl- and propyl p-hydr oxybenzoate, widely used as antimicrobials in food, and butyl p-hydroxybenz oate, which is used in cosmetic products, and their shared main metabolite p-hydroxybenzoic acid was investigated in a mouse uterotrophic assay, Immat ure B6D2F1 mice were treated with oral or subcutaneous doses of the test co mpounds for three consecutive days, p-Hydroxgybenzoic acid and butyl p-hydr oxybenzoate were also tested by the subcutaneous route in a rat uterotrophi c assay. A significant increase in the uterus weight at day 4 was considere d an oestrogenic effect. In the mouse assay, none of the compounds tested p roduced any oestrogenic response at dose levels up to 100 mg/kg body weight per day, for ethyl p-hydroxybenzoate even at a dose level of 1000 mg/kg bo dy weight per day. In immature Wistar rats, subcutaneous administration of butyl p-hydroxybenzoate produced a weak oestrogenic response at 600 mg/kg b ody weight per day. (C) 2000 Elsevier Science Ltd. All rights reserved.