INTERSEX AND LIVER ALTERATIONS INDUCED BY LONG-TERM SUBLETHAL EXPOSURE TO 17a-ETHINYLESTRADIOL IN ADULT MALE CNESTERODON DECEMMACULATUS (PISCES: POECILIIDAE)

BRIAN JONATHAN YOUNG,; GABRIELA CARINA LÓPEZ; DIEGO SEBASTIÁN CRISTOS; DIANA CRISTINA CRESPO ; GUSTAVO MANUEL SOMOZA; PEDRO CARRIQUIRIBORDE

ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY

SETAC PRESS

Lugar: Buenos Aires; Año: 2017 vol. 36 p. 1738 - 1745

0730-7268

Abstract: The aim of the present study was to assess the responses of the gonopodium morphology and the gonadal and liver histology ofadult male Cnesterodon decemmaculatus to sublethal long-term exposure concentrations of 17a-ethinylestradiol (EE2). Twoexperiments were conducted exposing the fish to waterborne concentrations of EE2 ranging from 20 ng/L to 200 ng/L for 8 wk, 12 wk,and 16 wk. Intersex gonads were observed after 8 wk and 16 wk in fish exposed to 200 ng EE2/L and 100 ng EE2/L, respectively.Oocytes? development from testis germ cells and replacement of the efferent duct periodic acid-Schiff?positive secretion surroundingspermatozeugmata by parenchymal tissue and duct structure alterations were the major observed changes in the gonads. In contrast, noresponse was observed in the gonopodium morphology. Liver histology was also altered, showing increasing steatosis, single-cellnecrosis to generalized necrosis, and disruption of acinar organization from 100 ng EE2/L to 200 ng EE2/L. In summary, the presentresults showed that although EE2 was not able to alter the morphology of a developed gonopodium, it was capable of inducingdevelopment of testicular oocytes in adult male C. decemmaculatus at environmentally relevant concentrations. Thus, externally normalbut intersex C. decemmaculatus males would be expected in the wastewater-receiving streams that the species inhabits. According to theliterature, the present study would be the first indicating estrogen-induced intersex in adult male poeciliid.