FIRST EVIDENCE OF FISH ENDOCRINE DISRUPTION IN A FRESHWATER SYSTEM OF THE CENTRAL REGION OF ARGENTINA.

HUED, A. C.; BISTONI, M. A.; WUNDERLIN, D.

Los Cocos, Provincia de Córdoba, Argentina

Simposio; Simposio SETAC Argentina. "Ecotoxicología y Contaminación"; 2006

Sociedad de Toxicología y Química Ambiental (Society of Environmental Toxicology and Chemistry)

Endocrine disruption have become one of the most controversial issues for the last few years as research has revealed an increasing number of diverse man-made chemicals that acts as hormones causing endocrine, reproductive and developmental dysfunctions. The impacts of municipal sewage treatment effluent on fish assemblages and other aquatic organisms have been well documented in different watersheds of Argentina. However, the research for evidence of the effects of environmental endocrine disruptors on fish has not yet begun. The main goal of this work was to determine whether impairment from sewage discharge on Suquía River Basin influences different somatic characteristics of fish, in order to looking for endocrine disruption evidences. We compared males of Jenynsia multidentata (Anablepidae, Cyprinodontiformes) from populations located below the municipal sewage discharge of Córdoba city with individuals from an unpolluted site located upstream Córdoba city. This fish species was selected for its high abundance and wide distribution. The somatic parameters measured were: standard length (SL), weight (W), condition factor (CF), gonopodium length (GL), gonopodium somatic index (Gonop-SI), gonopodium angle (GA) and protuberance area (PA).The general condition of J. multidentata decreased on the most polluted site where the individuals presented the lowest values of SL and W. They also showed a significant decrease of GL, Gonop-SI, GA and PA, which indicated an impairment of reproductive characteristics. According to our results J. multidentata could be affected by environmental estrogenic substances. The gonopodium shortening would presumably be via disruption of gonopodium growth and development during sexual maturation. This work gives an important evidence of endocrine disruption on fish fauna of Suquía River Basin. KEY WORDS: endocrine disruption, fish, freshwater, Argentina.