Environmental Xenoestrogens: Short-term Exposure of Low Doses of Lindane, Dieldrin, Dibutyl Phthalate, and Diethylhexyl Phthalate Increases Uterine Weight in Young Female Mice

Abstract

An in vivo method was developed to test the potential estrogenic activity of Lindane, Dieldrin, Dibutyl phthalate (DBP), and Diethylhexyl phthalate (DEHP) in 7-8 week old, virgin female mice. The mice were dosed for three consecutive days at the following dosages: a) 3.38 µM kg -1 day -1 for estrogen E2, b) 2.61 µM kg -1 day -1 for lindane, c.) 4.2 µM kg -1 day -1 for dieldrin, d) 6.43 µM kg -1 day -1 for DEHP and at e) 5.77 µM kg -1 day -1 for DBP. The uterine weights without fluids relative to mice weight, which was targeted as the biomarker (response), were significantly affected by the doses administrated. The statistical analyses showed increases in the average relative weights of uteri of 0.0071g for E2, 0.0092 for lindane, 0.0062 for dieldrin, 0.0068g for DEHP and 0.0056g for DBP compared with 0.00225 for the control (n = 5). These results show that all compounds used in this study have estrogenic effects in these mice under these conditions. Lindane was considered to be a strong estrogen while DBP was considered to be a weak estrogen. What are the implications of these findings for human exposure to similar low doses of any of these compounds, singly, sequentally or simultaneously? What are the policy and ethical responsibilities for addressing such potentially adverse effects within humans or wildlife.