Effect of the Antiandrogen DDE on Anthropometric Measures at Birth - Anogenital Distance

Experimental studies have documented the p'p-DDT, p'p-DDE (a metabolite of DDT) and other organochlorine (OC) compounds have estrogenic and/or antiandrogenic activities capable of altering normal endocrine functions. It has been postulated that exposure to these toxins during embriogenesis may cause urogenital malformations. However, this hypothesis has not yet been evaluated in humans populations with relatively high levels of exposure. The primary goal of this project is to study in utero exposure to DDE in relation to anogenital distance in humans. Anogenital distance is measured from a gender and species specific landmark on the genitalia, such as the junction of the penis and the scrotum in male humans, to the center of the anus. Altered anogenital distance is a sensitive manifestation of prenatal endocrine disruption in animal models; whether it is a sensitive endpoint in humans has not been studied. We will test the hypothesis that DDE, an androgen-receptor blocker, decreases anogenital distance in male humans who have been chronically but not occupationally exposed to DDT in Mexico. Study participants will be newborns and their mothers who live in the state of Chiapas, Mexico and who have been exposed to DDT through house spraying programs to control malaria in this area. Anogenital distance will be measured at birth and in utero exposure to DDE will be determined by measuring DDE in maternal blood.

Demonstration that p'p-DDT or p'p-DDE may interfere with normal endocrine functions during embriogenesis will provide a model to increase our understanding of how other- more prevalent-environmental estrogens may act and will open new possibilities for research and potential control of etiologic factors related with this important public health problem....