PERINATAL AND POSTNATAL DEVELOPMENTAL TOXICITY OF BETA-MYRCENE IN THERAT

Beta-Myrcene (MYR) and essential oils containing this monoterpene have been widely used as scenting agents in cosmetics, detergents, soaps, and as flavouring additives in food and beverages. Recently, MYR was r eported to be an analgesic substance and the active principle of lemon grass tea. Despite the importance of human exposure to MYR, its toxico logical profile has not been comprehensively studied. The aim of this study was to provide data on the peri- and postnatal developmental tox icity of this terpene. MYR (0.25, 0.5, 1.0 and 1.5 g/kg) in com oil wa s given by gavage to female Wistar rats from day 15 of pregnancy, part urition and throughout the period of lactation up to weaning (postnata l day 21). The progeny were examined at birth and subsequently to wean ing. Mortality, weight gain and physical signs of postnatal developmen t (ear unfolding, incisor emption, fur development and eye opening) we re evaluated. When the exposed offspring reached maturity (120 days) t heir reproductive capacity was assessed. No adverse effects on the off spring were seen with the lowest dose tested, but 0.5 g/kg and higher doses decreased birth weight, increased perinatal mortality and delaye d the day of appearance of landmarks of postnatal development. Moreove r, fertility was impaired in female offspring exposed to the two highe st doses of MYR. From the data presented in this paper the no-observed -adverse-effect level for peri- and postnatal developmental toxicity c ould be wt at 0.25 g beta-myrcene/kg body weight.