We investigated mammary gland differentiation and cell proliferation in rats after acute exposure to xenoestrogens. Pubertal female Sprague-Dawley rats (six/group) were treated for 1 week with diethylstilbestrol (DES), genistein, o,p'-DDT, Aroclor 1221, Aroclor 1254, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), or the vehicle, sesame oil. Animals were killed 18 hr after the last treatment. Analy...

DDT (dichlorodiphenyltrichloroethane), a pesticide once used widely in agriculture and now limited to public health use, remains a controversial chemical because of a combination of benefits and risks. DDT or its breakdown products are ubiquitous in the environment and in humans. Compounds in the DDT family have endocrine actions and have been associated with reproductive toxicity. A previous s...

BACKGROUND Previous studies of DDT and breast cancer assessed exposure later in life when the breast may not have been vulnerable, after most DDT had been eliminated, and after DDT had been banned. OBJECTIVES We investigated whether DDT exposure in young women during the period of peak DDT use predicts breast cancer. METHODS We conducted a prospective, nested case-control study with a media...

Complete sex reversal of fish is accomplished routinely in aquaculture practices by exposing fish to exogenous sex steroids during gonadal differentiation. A variety of environmental chemicals are also active at sex steroid receptors and theoretically possess the potential to alter normal sexual differentiation in fish. However, in controlled environmental chemical exposures to date, only parti...

Organochlorine pesticides (OCPs), viz. β-hexachlorocyclohexane (β-HCH), γ-HCH, aldrin, dieldrin, endrin, heptachlor, endosulfan-I, endosulfan-II, heptachlor endoepoxide, heptachlor exoepoxide, mirex, dicofol, o,p'-dichlorodiphenyltrichloroethane (o,p'-DDT), p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), dichlorodiphenyldichloroethane (DDD), and dichlorodiphenyltrichloroethylene (DDE) and 12 o...

Mallard ducks were fed diets containing various levels of technical DDT or chemically pure p,p'-DDT, or dieldrin. Either technical DDT or p,p'-DDT at 20 ppm or greater, or dieldrin at I 0 ppm caused a statistically significant reduction in e9gshell thickness, weight, and calcium. Shells of eggs from ducks fed 40 ppm of p,p -DDT were about 20% thinner than those from control ducks, and shells of...

The cytokinesis-block micronucleus (CBMN) assay is one of the standard cytogenetic tools employed to assess chromosomal damage subsequent to exposure to genotoxic/cytotoxic agents, and is widely applicable to plant, animal and human cells. In the present study, the CBMN assay was used to assess the baseline damage in binuclear human peripheral blood lymphocytes exposed to 25 microg/L p,p'-DDT f...

Hermansson, A. 2007. Effects on the reproductive system in domestic fowl (Gallus domesticus) after embryonic exposure to estrogenic substances. Doctor’s dissertation ISSN 1652-6880 ISBN 978-91-576-7319-0 Environmental pollutants with estrogenic activity have a potential to disrupt oestrogendependent developmental processes. Thus, the aim of this thesis was to investigated how embryonic exposure...

The insecticide DDT is still used in specific areas of South Africa for indoor residual spray (IRS) to control malaria vectors. Local residents could be exposed to residues of DDT through various pathways including indoor air, dust, soil, food and water. The aims of this study were to determine the levels of DDT contamination, as a result of IRS, in representative homesteads, and to evaluate th...

BACKGROUND The organochlorine dichlorodiphenyltrichloroethane (DDT), a known estrogen mimic and endocrine disruptor, has been linked to animal and human disorders. However, the detailed mechanism(s) by which DDT affects cellular physiology remains incompletely defined. OBJECTIVES We and others have shown that DDT activates cell-signaling cascades, culminating in the activation of estrogen rec...