Spatial and temporal biomarkers responses of Astyanax jacuhiensis (Cope, 1894)(Characiformes: Characidae) from the middle rio Uruguai, Brazil

Abstract

Due to intense agricultural activity in the rio Uruguai (South Brazil), there is the potential for aquatic contamination by agrochemicals. In this region, there are many reservoirs to meet the water demand for rice fields, forming lentic environments. In line with this information, the aim of this study was to show a comparative analysis of some biomarkers, such as lipid peroxidation (TBARS), gluthatione S-transferase (GST), non-protein thiols (NPSH), amino acids (AA) and piscine micronucleus tests (MNE) in Astyanax jacuhiensis from lentic and lotic environments in the middle rio Uruguai region, comparing warm and cold seasons. Eight pesticides were found in water samples, with propoxur having the highest concentration found in both environments and seasons. Fish from the warm season showed higher levels of biochemical biomarkers, and fish from the cold season showed higher levels of MNE and AA. TBARS and AA presented higher levels in fish from the river, while GST, NPSH, MNE and AA presented higher levels in fish from dams. These environments have different characteristics in terms of redox potential, aeration, sedimentation, trophic structure, agrochemicals input and others, which may affect the physiological and biochemical responses of fish in against adverse situations.Devido à intensa atividade agrícola no rio Uruguai (Sul do Brasil), há potencial para contaminação aquática por agrotóxicos. Há muitos reservatórios para atender a demanda de água de campos de arroz, formando ambientes lênticos. De acordo com estas informações, o objetivo do presente estudo foi mostrar uma análise comparativa de alguns biomarcadores como a peroxidação lipídica (TBARS), glutationa S-transferase (GST), tióis não-protéicos (NPSH), aminoácidos (AA) e teste písceo de micronúcleos (MNE) em Astyanax jacuhiensis amostrados em ambientes lóticos e lênticos da região do médio rio Uruguai, comparando estações quentes e frias. Oito pesticidas foram encontrados em amostras de água, sendo propoxur a maior concentração encontrada em ambos os ambientes e estações. Peixes da estação quente apresentaram maiores níveis de biomarcadores bioquímicos e peixes da estação fria apresentaram maiores níveis de MNE e AA. TBARS e AA apresentaram maiores níveis nos peixes de rio, enquanto GST, NPSH, MNE e AA apresentaram níveis mais elevados em peixes da represa. Estes ambientes têm características diferentes, com potencial redox, aeração, sedimentação, estrutura trófica, a entrada de agroquímicos e outros que podem afetar as respostas fisiológicas e bioquímicas de peixe contra situação adversa.

Use of nontarget organism Chironomus sancticaroli to study the toxic effects of nanoatrazine

“…In the China, Tan et al (2020) reported the occurrence of atrazine (4.1 μg L −1 ) in surface water, exceeding 2 times the limit allowed by the Ministry of Health (2007). In Brazil, in aquatic ecosystems, have been detected atrazine concentrations (2.7, 2.89, 4.1, 4.92 and 9.33 μg L −1 ) until 4.66 times higher than the permitted by Brazilian legislation for freshwater, as well as levels that exceed the value stipulated by United State and China (Armas et al 2007;Della-Flora et al 2019;Loro et al 2015;Moreira et al 2012). This is worrying, since the results obtained in the present study indicate that the concentration of 2 μg L −1 caused Although atrazine has been detected in low concentrations in surface waters in several countries, it must be monitored in environmental studies, since it has also been detected with values above what is allowed (Table 3), because your presence in aquatic environments can affect the ecosystem, causing an imbalance in the environment (Albuquerque et al 2020).…”

“…However, this herbicide still is widely used in other countries, an example Brazil, where the National Environmental Council (CONAMA, Resolution 357/2005, updated and modified by Resolution 430/2011) establishes that the maximum concentration of atrazine for freshwater (surface waters intended for human consumption and the protection of aquatic life) must be 2 μg L −1 . Despite this established value, concentrations higher than the recommended have been found in aquatic environments (Armas et al 2007;Della-Flora et al 2019;Loro et al 2015;Moreira et al 2012).…”