Bentazon (Basagran) belongs to the chemical group of benzothiadiazinones. Thus, this study aimed to estimate the influence of herbicide bentazon (3 µg.L, 6 µg.
View Article and Find Full Text PDFThe high demand for food consequently increases the entry of agricultural residues into water resources, and this phenomenon can affect non-target organisms in different ways. Environmentally relevant pesticide effects (per se or in combinations) are scarce in the scientific literature. Therefore, the aim of this study was to investigate: (1) the presence of pesticide residues in an important Brazilian source of water supply and power generation (Jacuí river), during 1 year of monitoring.
View Article and Find Full Text PDFThe insecticides imidacloprid (IMI), a neonicotinoid, and propoxur (PRO), an N-methylcarbamate compound, are pesticides widely used throughout the world. Although they are not used together to combat pests, both are often found in freshwater near agricultural areas. Thereby, the goal of this study was to evaluate the additive effects of IMI and PRO mixtures at environmental concentrations in relation to isolated compounds on Rhamdia quelen, a neotropical fish.
View Article and Find Full Text PDFBrazilian freshwater ecosystems are continuously exposed to pesticides and domestic sewage. The Uruguay River was chosen for this study because of its international importance, as it flows through Brazil, Argentina, and Uruguay. It receives contaminants such as pesticides and domestic residues.
View Article and Find Full Text PDFFreshwater ecosystems are constantly threatened by the advance of agricultural activities. Abiotic variables (such as temperature, ammonia, and nitrite) and contaminants (e.g.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
December 2020
Understanding how temperature alone affects biomarkers commonly used in ecotoxicology studies and biomonitoring programs is important to obtain a more real response in field studies, especially in freshwater. Thus, we analyzed the behavioral responses, the lethality, and the biochemical biomarkers in the freshwater crustacean Aegla longirostri at different water temperatures. Animals were exposed under laboratory conditions, to 18 °C, 21 °C, 24 °C, and 26 °C for 48 h.
View Article and Find Full Text PDFIntensive agricultural and livestock activities demand high pesticide use and, consequently, contaminants reach aquatic ecosystems. In the lower Jacuí River, southern Brazil, there is a lack of knowledge about pesticide residues in water samples and the biochemical responses in native fish species. Thus, this study aimed to estimate the influence of pesticide residues and water parameters to biomarker responses in the native fish Astyanax spp.
View Article and Find Full Text PDFAquatic environments are affected by the use of pesticides in agricultural areas near rivers. To assess the impact of pesticide residues on affected environments Danio rerio (zebrafish) embryos have become an alternative model for biomonitoring studies. In the present study, zebrafish embryos were used as bioindicator of water quality in the Vacacaí river, located in the city of Santa Maria, southern Brazil.
View Article and Find Full Text PDFZinc is an essential trace mineral that is involved in many biological processes. In elevated concentrations, this metal may have toxic effects for aquatic organisms. Physicochemical properties of water, such as salinity and hardness, can influence the bioavailability of zinc and, therefore its toxicity in aquatic environments.
View Article and Find Full Text PDFThis work investigated the preventive effect of diphenyl diselenide [(PhSe)] against the toxic effects of mercury in silver catfish (Rhamdia quelen). The animals were treated during 30 consecutive days with a (PhSe) supplemented feed (3.0 mg kg) or commercial feed.
View Article and Find Full Text PDFAlthough designed to control pests selectively, there is some evidence that environmental contamination by pesticides increases risks for humans and wildlife. In the present study, we evaluated biomarkers of oxidative stress in Astyanax jacuhiensis exposed to (5, 15 and 30 µg L) of carbamate Propoxur (PPX) for 96 h. Glutathione S-transferase (GST) in liver and gills showed reduced activity in all PPX concentrations tested.
View Article and Find Full Text PDFAtrazine (ATZ) is a herbicide worldwide used. That can cause oxidative damage in non-target organisms, such as fish. Furthermore, the threat of exposure to pesticides together with poor nutrition is hazardous to the normal development of fish, and supplementation of the fish diet with antioxidants compounds is an alternative approach to prevent the hazardous effects of pesticide exposure.
View Article and Find Full Text PDFCropping systems based on intensive land use and continuous application of agricultural chemicals inflict a threat to aquatic organisms since these substances will inevitably be carried in to water bodies where they can accumulate, particularly in lentic sites. Pesticides exposure in aquatic animals can cause changes that can be quantified through biomarkers. Thus, this study aimed to investigate the effects of season on oxidative stress and neurotoxicity biomarkers in Loricariichthys anus from a subtropical reservoir surrounded by agricultural areas in southern Brazil.
View Article and Find Full Text PDF