Diethylhexyl phthalate magnifies deposition of 14C–bisphenol A in reproductive tissues of mice

Endocrine disrupting chemicals are found in diverse common products, including cosmetics, food packaging, thermal receipt paper and plastic containers. This exposes most people in developed countries through ingestion, skin absorption and inhalation. Two ubiquitous endocrine disrupting chemicals, bisphenol A (BPA) and diethylhexyl phthalate (DEHP) can interact in disrupting blastocyst implantation in inseminated females. We hypothesized that DEHP might increase the bioavailability of BPA in tissues by competing for metabolic enzymes. We injected 0, 3, 9 or 18 mg DEHP into female and male mice and allowed 30 min for the chemical to circulate before giving them a food supplement containing 50 μg kg^{-1 14} C-BPA. Animals were dissected 1 h following ¹⁴ C-BPA administration and various tissue samples were acquired. Samples were solubilized and radioactivity was measured via liquid scintillation counting. In cycling females, DEHP increased BPA deposition in the muscle, uterus, ovaries and blood serum relative to controls. In peri-implantation females, DEHP increased deposition of BPA in the uterus, ovaries and serum relative to controls. In males, DEHP doses increased BPA deposition in serum and epididymis relative to controls. These results are consistent with the hypothesis that DEHP competes with BPA for conjugating enzymes such as UDP-glucuronosyltransferase, thereby magnifying the presence of BPA in estrogen-binding reproductive tissues. Copyright © 2017 John Wiley & Sons, Ltd.