Kembra L Howdeshell
Affiliation: U.S. Environmental Protection Agency
- A mixture of five phthalate esters inhibits fetal testicular testosterone production in the sprague-dawley rat in a cumulative, dose-additive mannerKembra L Howdeshell
Reproductive Toxicology Division, NHEERL, ORD, United States Environmental Protection Agency USEPA, Research Triangle Park, North Carolina 27711, USA
Toxicol Sci 105:153-65. 2008..These data demonstrate that individual phthalates with a similar mechanism of action can elicit cumulative, dose additive effects on fetal testosterone production and pregnancy when administered as a mixture...
- Mechanisms of action of phthalate esters, individually and in combination, to induce abnormal reproductive development in male laboratory ratsKembra L Howdeshell
Reproductive Toxicology Division, National Health and Environmental Effects Laboratory, Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, NC 27711, USA
Environ Res 108:168-76. 2008..Since phthalate ester metabolites are detected in maternal and fetal body fluids, and androgen-signaling and insl3 are highly conserved among mammals, phthalates may potentially affect human reproductive development...
- Gestational and lactational exposure to ethinyl estradiol, but not bisphenol A, decreases androgen-dependent reproductive organ weights and epididymal sperm abundance in the male long evans hooded ratKembra L Howdeshell
US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Reproductive Toxicology Division, Research Triangle Park, North Carolina 27711, USA
Toxicol Sci 102:371-82. 2008..05-1.5 mug/kg/day did not significantly affect any male endpoint in the current study. These results demonstrate that developmental exposure to oral micromolar doses of EE can permanently disrupt the reproductive tract of the male rat...
- Cumulative effects of in utero administration of mixtures of "antiandrogens" on male rat reproductive developmentCynthia V Rider
MD 72, Endocrinology Branch, Reproductive Toxicology Division, NHEERL, ORD, U S Environmental Protection Agency, RTP, North Carolina 27713, USA
Toxicol Pathol 37:100-13. 2009..In this study, the complex mixture behaved in a dose-additive manner. Our results indicate that compounds that act by disparate mechanisms of toxicity display cumulative, dose-additive effects when present in combination...
- Dose-response assessment of fetal testosterone production and gene expression levels in rat testes following in utero exposure to diethylhexyl phthalate, diisobutyl phthalate, diisoheptyl phthalate, and diisononyl phthalateBethany R Hannas
Toxicology Assessment Division, Reproductive Toxicology Branch, U S Environmental Protection Agency, National Health and Environmental Effects Research Laboratory, Research Triangle Park, North Carolina 27711, USA
Toxicol Sci 123:206-16. 2011....
- Transgenerational effects of Di (2-ethylhexyl) phthalate in the male CRL:CD(SD) rat: added value of assessing multiple offspring per litterLeon Earl Gray
Endocrinology Branch, RTD, NHEERL, ORD, USEPA, Research Triangle Park, North Carolina 27711, USA
Toxicol Sci 110:411-25. 2009....
- The herbicide linuron reduces testosterone production from the fetal rat testis during both in utero and in vitro exposuresVickie S Wilson
U S Environmental Protection Agency, Office of Research and Development, NHEERL, Research Triangle Park, NC, USA
Toxicol Lett 186:73-7. 2009..These results indicate the malformations induced by linuron and phthalate esters in male offspring are similar because both reduce fetal T levels during the critical period of sex differentiation but suggest that the mechanisms differ...
- Differential expression of the phthalate syndrome in male Sprague-Dawley and Wistar rats after in utero DEHP exposureVickie S Wilson
U S Environmental Protection Agency, ORD, NHEERL, Reproductive Toxicology Division, MD 72, Research Triangle Park, NC 27711, USA
Toxicol Lett 170:177-84. 2007....
- Estrogenic chemicals in plastic and oral contraceptives disrupt development of the fetal mouse prostate and urethraBarry G Timms
Division of Basic Biomedical Sciences, University of South Dakota School of Medicine, Vermillion, SD 57069, USA
Proc Natl Acad Sci U S A 102:7014-9. 2005..Acceleration in the rate of proliferation of prostate epithelium during fetal life by small amounts of estrogenic chemicals could permanently disrupt cellular control systems and predispose the prostate to disease in adulthood...
- Exposure to a low dose of bisphenol A during fetal life or in adulthood alters maternal behavior in micePaola L Palanza
Department of Evolutionary and Functional Biology, Parma University, Parco Area delle Scienze 11A, 43100 Parma, Italy
Environ Health Perspect 110:415-22. 2002..The changes seen in maternal behavior may be the result of a direct effect of BPA on the neuroendocrine substrates underlying the initiation of maternal behavior...
- Low phytoestrogen levels in feed increase fetal serum estradiol resulting in the "fetal estrogenization syndrome" and obesity in CD-1 miceRachel L Ruhlen
Division of Biological Sciences, University of Missouri Columbia, Columbia, Missouri 65211, USA
Environ Health Perspect 116:322-8. 2008..Although estrogenic chemicals can disrupt development of the reproductive system, there is debate about whether phytoestrogens in soy are beneficial, benign, or harmful...
- Cumulative effects of dibutyl phthalate and diethylhexyl phthalate on male rat reproductive tract development: altered fetal steroid hormones and genesKembra L Howdeshell
North Carolina State University, Department of Molecular Biomedical Sciences, Raleigh, North Carolina 27606, USA
Toxicol Sci 99:190-202. 2007....
- Bisphenol A is released from used polycarbonate animal cages into water at room temperatureKembra L Howdeshell
Division of Biological Sciences, University of Missouri, Columbia, Missouri, USA
Environ Health Perspect 111:1180-7. 2003..Our findings suggest that laboratory animals maintained in polycarbonate and polysulfone cages are exposed to BPA via leaching, with exposure reaching the highest levels in old cages...
- Prochloraz inhibits testosterone production at dosages below those that affect androgen-dependent organ weights or the onset of puberty in the male Sprague Dawley ratChad R Blystone
Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, North Carolina 27695, USA
Toxicol Sci 97:65-74. 2007....
- Sensitivity of fetal rat testicular steroidogenesis to maternal prochloraz exposure and the underlying mechanism of inhibitionChad R Blystone
Department of Environmental and Molecular Toxicology, NC State University, Raleigh, NC 27695, USA
Toxicol Sci 97:512-9. 2007..These results demonstrate that PCZ lowers testicular testosterone synthesis by inhibiting CYP17 activity which likely contributes to the induced malformations in androgen-dependent tissues of male offspring...