Quantificação de substâncias com atividade estrogênica e caracterização da toxicidade embriolarval em zebrafish (Danio rerio) nos efluentes das estações de tratamento de esgotos sul e norte e no Lago Paranoá, Brasília-DF

Abstract

Sewage release results in the disposal of various pollutants in water bodies, including the so-called emerging pollutants. Among these are the endocrine disrupters, exogenous agents that mimic the natural hormones binding to cell receptor sites activating or blocking cell signaling pathways that trigger hormone function. These pollutants have been found in environmental samples all over the world, including Brazil, at low concentrations causing effects to exposed organisms. In this context, the aims of this study were to investigate the occurrence of three emerging pollutants with estrogenic activity (17β-estradiol-E2, 17α-ethinylestradiol-EE2 and bisphenol A-BPA) in water samples from Paranoá Lake and effluent of Sewage Treatment Plants (STPs), North and South, in Brasília-DF; Evaluate the toxicity of both environmental samples as the pollutant most frequently detected (BPA) to zebrafish embryonic development. In addition, it was tested, in the same animal model, sub lethal doses of BPA by biochemical markers. Finally, the environmental concentrations detected were compared with effect concentrations, described in literature, for aquatic animals from the first and second trophic levels. In the quantification analysis, samples were processed by solid phase extraction (SPE) and subjected to an analytical method developed in HPLC/DAD/FL. In this case, the mobile phase was acetonitrile with water in the ratio 40:60 (v/v), acidified with trifluoroacetic acid (0,12%) in isocratic condition. All the toxicity assays was performed following the OECD Protocol 236 (Guideline on Fish Embryo Toxicity Test-FET). The results showed that BPA was the most predominant pollutant in analyzed samples, with 100% of detection in the treated wastewater and 23% in surface water. The concentrations found were between <394-1231 ng L-1 in the effluent and <197-644 ng L-1 in Lake samples. Other compounds, E2 and EE2, showed low frequency of detection (<18%) in both Lake and effluent samples and, for only one effluent sample, EE2 was quantified in concentration of 591 ng L-1 .Toxicity tests showed that water samples from Paranoá Lake and South STP effluent were no toxic to zebrafish embryos; BPA is slightly toxic to zebrafish embryos (LC50 13.45 mg L-1) and was rapidly degraded in an aqueous medium (4-5 days). However, effects on hatching (CEO = 10 mg L-1), delayed pigmentation, craniofacial formation (CEO = 21.54 mg L-1) and inhibition of GST (CEO = 11.68 ug L-1) were observed in embryos exposed to BPA. In addition, the levels at which the three pollutants were found in the analyzed samples are among the effects concentrations reported in the literature for aquatic animals of the first and second trophic levels, with the exception of BPA for primary consumers. Moreover, the literature suggests that BPA tends to be less toxic than E2 and EE2. It follows that, despite being the most often detected in samples, BPA is the one with less toxicity to aquatic animals. This data contribute to enlarge the database related to the presence of contamina...

Occurrence of 17α-ethinylestradiol in Paranoá Lake watershed (Brasília, Brazil): sewage, freshwater and treated water

“…In this case, regions that adopt contraceptive pills as birth control will probably exhibit higher EE2 concentrations. The EE2 concentrations detected in the treated (P2, P4 and P6) sewage ranged from 0.23 up to 1.50 ng L -1 , lower than that reported by Silva (2015), of about 500 ng L -1 in treated sewage from the same plants evaluated in 2015. The differences observed between these two years (2015 and 2017) may be due to planning that may have forced changes in the plant operating systems.…”

Avaliação ecotoxicológica da água residuária do café por meio de bioensaios com Danio rerio

“…promover respostas rápidas e de fácil interpretação durante um curto período de exposição. Várias características favorecem o uso desta espécie no monitoramento ecotoxicológico, entre elas: grande adaptabilidade, facilidade no cultivo e manutenção, facilidade de reprodução em laboratório, entre outros (Silva, 2015).…”

“…Durante os ensaios para estimar a CL 50-48h, logo nas primeiras horas de exposição às amostras das soluções-teste, foram observadas mudanças significativas no comportamento dos animais. Tais mudanças ocorrem, principalmente, pela baixa concentração de oxigênio dissolvido nas amostras de ARC na qual os animais foram expostos, Silva et al (2015) explica que a redução de oxigênio dissolvido ocorre devido ao elevado consumo de matéria orgânica por microorganismos existentes neste efluente.…”

“…A qualidade da bebida oriunda dos grãos brasileiros é um fator relevante para o sucesso do produto, além disso, a avaliação da qualidade do café é feita por vários parâmetros que podem prejudicar a qualidade e variam do cultivo até a industrialização (Silva et al, 2015).…”

Removal of Bisphenol S (BPS) by Adsorption on Activated Carbons Commercialized in Brazil

“…Concentrations of BPA have been detected in Lake Paranoá, located in the Federal District (FD), ranging from 0.002 to 1.231 μg/L [ 9 , 10 , 11 , 12 ]. In 1960, Brasília, the capital of Brazil, was founded, and since then, the population has increased.…”