Avaliação in vivo do potencial estrogênico de amostra de água para consumo humano produzida por estação de tratamento do estado de São Paulo

• Autor(a) principal: Vaccari, Carolina [UNESP]
• Data de Publicação: 2013
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/121651
• topic: Água - Qualidade; Agua - Analise; Desreguladores endócrinos; Expressão gênica; Toxicologia; Water quality

Introduction: The release of raw sewage into rivers and lakes has drawn attention to an important issue nowadays: the water quality. Substances with estrogenic activity (xenoestrogens) are the best known endocrine disruptors, and these, as well as other chemical substances, may remain in the water even after the conventional treatment. Objective: This study investigated the estrogenic potential of a drinking water sample from a Sao Paulo State Water Treatment Plant, using a standardized bioassay: the uterotrophic assay (OECD; nº 440), supplemented by the vaginal cornification evaluation. Materials and methods: The drinking water distributed to the population was collected and concentrated as an extract using a cartridge filter for organic substances. Water extracts were chemically evaluated for emerging contaminants and also in vitro by a bioluminescent yeast assay with estrogen/androgen human receptors (BLYES, BLYAS). In vivo assay was conducted with female 21- day old Wistar rats that were exposed by gavage to drinking water extracts during 03 days at doses of 33.3, 166.5, and 333.0 mL equivalent of water/kg body weight, modeling a daily ingestion of 2 L, 5 L and 10 L of drinking water by a 60 kg human being. Results: Traces of caffeine (21ug/L), atrazine (2.2 ng/L), imidacloprid (0.88 ng/L) and fungicides like carbendazim (0.22 ng/L), azoxystrobin (0.23 ng/L) and tebuconazole (0.19 ng/L) were detected in the water extract by LC-MS/MS. These substances are emerging contaminants and potential endocrine disruptors. Androgen or estrogen agonistic extract activities resulted negative by the bioluminescent yeast assay (BLYAS, BLYES). Accordingly, the in vivo assay was negative: there was no significant increase of the uterus wet weight in the uterotrophic assay and no histological alterations in the uterus nor vaginal ephitelium. Serum levels of 17-βestradiol, FSH, LH and testosterone were not significantly influenced by treatment in this ...