We conducted three experiments to determine whether BPA leached out of different types of animal caging under neutral conditions by using HPLC-grade water as the solvent and at room temperature (23 [+ or -] 2[degrees]C).
To study the in vivo effects of BPA exposure through cage and water bottle materials, we measured the uterine wet weight of prepubertal female mice housed in used polycarbonate cages with used polycarbonate water bottles versus mice housed in used polypropylene cages with glass water bottles; the objective was to establish the two extreme conditions of maximum and lowest exposure to BPA via caging materials.
A difference between our study and prior studies of the leaching of BPA is that we examined whether BPA would migrate passively out of used polycarbonate caging under the moderate conditions of standing undisturbed (not shaken during the experiment), normal room temperature, and a neutral, polar solvent (HPLC-grade water).