DEVELOPMENTAL ABNORMALITIES OF THE GONAD AND ABNORMAL SEX-HORMONE CONCENTRATIONS IN JUVENILE ALLIGATORS FROM CONTAMINATED AND CONTROL LAKESIN FLORIDA

The reproductive developments of alligators from a contaminated and a control lake in central Florida was examined. Lake Apopka is adjacent to an EPA Superfund site, listed due to an extensive spill of dicofol and DDT or its metabolites. These compounds can act as estrogens. Cont aminants in the lake also have been derived from extensive agricultura l activities around the lake that continue today and a sewage treatmen t facility associated with the city of Winter Garden, Florida. We exam ined the hypothesis that an estrogenic contaminant has caused the curr ent failure in recruitment of alligators on Lake Apopka. Supporting da ta include the following: At 6 months of age, female alligators from L ake Apopka had plasma estradiol-17 beta concentrations almost two time s greater than normal females from the control lake, Lake Woodruff. Th e Apopka females exhibited abnormal ovarian morphology with large numb ers of polyovular follicles and polynuclear oocytes. Male juvenile all igators had significantly depressed plasma testosterone concentrations comparable to levels observed in normal Lake Woodruff females but mor e than three times lower than normal Lake Woodruff males. Additionally , males from Lake Apopka had poorly organized testes and abnormally sm all phalli. The differences between lakes and sexes in plasma hormone concentrations of juvenile alligators remain even after stimulation wi th luteinizing hormone. Our data suggest that the gonads of juveniles from Lake Apopka have been permanently modified in ovo, so that normal steroidogenesis is not possible, and thus normal sexual maturation is unlikely.