Bisphenol S modulates concentrations of bisphenol A and oestradiol in female and male mice.

1. Concern over endocrine-disrupting actions of bisphenol A (BPA) has prompted some manufacturers to remove it from consumer products. Among the chemical replacements in "BPAfree" products are other bisphenol analogues, such as bisphenol S (BPS). Given evidence that BPA and BPS possess similar oestrogenic activity, their capacity to interact and disrupt oestrogen homeostasis should be examined. 2. We investigated whether BPS can modulate concentrations of 14C-BPA, exogenous 3Hoestradiol (E2), or natural E2. CF-1 mice were each given a single subcutaneous injection of oil containing 0 (vehicle), 1, 3, or 9mg BPS, then given a dietary supplement containing either 50 lg/kg 14C-BPA or 5 lCi (14.5 ng) 3H-E2. BPS treatment elevated 14C-BPA concentrations in blood serum and certain reproductive organs of both sexes, but reduced 3H-E2 concentrations in blood serum of females. In another experiment, natural E2 was measured in urine 2-12 h after injection of 0 (vehicle), 1, or 3mg BPS. BPS reduced E2 concentrations at 10 h after injection in both sexes. 3. These results are consistent with evidence that BPS and BPA compete for access to metabolic enzymes, and that BPS can disrupt oestrogen homeostasis. These findings demonstrate the importance of considering multiple toxicants when determining regulatory exposure limits. [ABSTRACT FROM AUTHOR]