Ronald N. Shiotsuka

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Bisphenol A (BPA) was evaluated at concentrations of 0, 0.015, 0.3, 4.5, 75, 750, and 7500 ppm ( approximately 0.001, 0.02, 0.3, 5, 50, and 500 mg/kg/day of BPA) administered in the diet ad libitum to 30 CD((R)) Sprague-Dawley rats/sex/dose for 3 offspring generations, 1 litter/generation, through F3 adults. Adult systemic toxicity at 750 and 7500 ppm in(More)
Bisphenol A (BPA) is a monomer used in the manufacture of a multitude of chemical products, including epoxy resins and polycarbonate. The objective of this study was to evaluate the effects of BPA on male sexual development. This study, performed in CF-1 mice, was limited to the measurement of sex-organ weights, daily sperm production (DSP), epididymal(More)
Dietary bisphenol A (BPA) was evaluated in a mouse two-generation study at 0, 0.018, 0.18, 1.8, 30, 300, or 3500 ppm (0, 0.003, 0.03, 0.3, 5, 50, or 600 mg BPA/kg/day, 28 per sex per group). A concurrent positive control group of dietary 17beta-estradiol (0.5 ppm; 28 per sex) confirmed the sensitivity of CD-1 mice to an endogenous estrogen. There were no(More)
The pharmacokinetics of bisphenol A (BPA), including the quantification of the major BPA metabolite BPA-monoglucuronide conjugate (BPA-glucuronide) was studied in Sprague-Dawley rats at different stages of gestation. 14C-BPA was administered orally at 10 mg BPA/kg body weight (0.2 mCi/rat) to nongravid rats and to other groups on gestation days (GD) 6, 14,(More)
Bisphenol A (BPA) is a chemical used primarily as a monomer in the manufacture of numerous chemical products, such as epoxy resins and polycarbonate. The objective of this study was to evaluate potential effects of BPA on sexual development of male rats and was designed to clarify low-dose observations reported as preliminary results by Sharpe et al.(More)
Previous studies demonstrated the rapid clearance of bisphenol A (BPA) from blood following oral administration to adult rats with the principal metabolite being BPA-monoglucuronide (BPA-glucuronide). Since the ontogeny of glucuronyl transferases (GT) differs with age, the pharmacokinetics of BPA were studied in neonatal animals. (14)C-BPA was administered(More)
This study was conducted to determine the potential of bisphenol A (BPA) to induce functional and/or morphological effects to the nervous system of F(1) offspring from dietary exposure during gestation and lactation according to the Organization for Economic Cooperation and Development and U.S. Environmental Protection Agency guidelines for the study of(More)
The received dose, tissue distribution, metabolism, routes and rates of excretion of [(14)C]-4, 4(')-methylenediphenyl diisocyanate (MDI) were investigated in the male rat following a 6-h inhalation exposure to [(14)C]-MDI at a target concentration of 2 mg m(-3). The mean dose received was equivalent to 0.078 mg MDI per animal, of this between 25 and 32% of(More)
The potential exposure of workers to both 2,4-toluene diisocyanate (2,4-TDI) and 2,6-TDI led to an investigation of the comparative respiratory sensitization potential of these two isomers. Separate groups of guinea pigs were either sham exposed or exposed to one of the isomers 3 h/day for 5 consecutive days (sensitization phase). The mean concentration(More)
Fischer-344 rats were exposed to 0.0, 0.3, 1.0, or 2.0 mg Cd/m3 as CdCl2 aerosol for 6 h/d, 5 d/wk, for 62 exposure days. Exposure to 2.0 mg Cd/m3 resulted in rapid weight loss, and all of the animals died within the first 45 exposure days. As a group, female rats survived significantly longer than the males. Exposure to Cd resulted in dose-dependent(More)