Octamethylcyclotetrasiloxane induces estrogenic effects in B6C3F1 mice.
Munson-A; He-B; Thodes-Bower-S; Miller-M; Meade-J
Toxicology 2001 Jul; 164(1-3):130
Octamethylcyclotetrasiloxane (D4) is a low molecular weight silicone which is extensively used in personal care products and foods because of its lubricity, low surface tension, and low heat of vaporization. The estrogenic activity of D4 was evaluated in these studies using both in vitro and in vivo methods. Intact female B6C3F1 mice demonstrated a progressive dose dependant decrease in serum estradiol levels following oral exposure to D4 with up to 50% suppression observed following a dose of 1000 mg/kg. Ovariectomized mice showed a dose-dependant increase in uterine weight (up to 3-fold) following D4 exposure which was blocked by pretreatment with the estrogen receptor atangonist ICI 182, 780. Uterine peroxidase activity was also increased in D4 exposed mice. In vitro, D4 at concentrations of 10^-6 and 10^-4M demonstrated dose-dependent competition with 3H-estradiol in an estrogen receptor-alpha binding assay. These data indicate that D4 has estrogenic activity which may be mediated through estrogen receptors.
Silicon-compounds; Estrogenic-hormones; Laboratory-animals; Dose-response; Exposure-levels; Animal-studies; Animals; Uterus; In-vitro-studies; Serological-techniques; Peroxidases