Chiral pharmaceuticals, racemic or enantiomerically pure forms and their metabolites, can reach aquatic ecosystems via wastewater effluents (inefficient treatment operations) or by direct human disposal. They may negatively affect nontarget organisms even at low environmental concentrations. To make an accurate risk evaluation, the (eco)toxicity of both enantiomers needs to be assessed.
View Article and Find Full Text PDFThe increased detection of the recreational drug 3,4-methylenedioxymethamphetamine (MDMA) in aquatic ecosystems, has raised concern worldwide about its possible negative impacts on wildlife. MDMA is produced as racemate but its enantioselective effects on non-target organisms are poorly understood. Therefore, this study aimed to provide a comprehensive study of the toxicity of MDMA and its enantiomers in the early life stages of zebrafish (Danio rerio).
View Article and Find Full Text PDFButylone (BTL) is a chiral synthetic cathinone available as a racemate and reported as contaminant in wastewater effluents. However, there are no studies on its impact on ecosystems and possible enantioselectivity in ecotoxicity. This work aimed to evaluate: (i) the possible ecotoxicity of BTL as racemate or its isolated (R)- and (S)- enantiomers using Daphnia magna; and (ii) the efficiency of advanced oxidation technologies (AOTs) in the removal of BTL and reduction of toxic effects caused by wastewaters.
View Article and Find Full Text PDFSynthetic cathinones (SC) are drugs of abuse that have been reported in wastewaters and rivers raising concern about potential hazards to non-target organisms. In this work, 44 SC were selected for in silico studies, and a group of five emerging SC was prioritized for further in vivo ecotoxicity studies: buphedrone (BPD), 3,4-dimethylmethcathinone (3,4-DMMC), butylone (BTL), 3-methylmethcathinone (3-MMC), and 3,4-methylenedioxypyrovalerone (MDPV). In vivo short-term exposures were performed with the protozoan (28 h growth inhibition assay) and the microcrustacean by checking different indicators of toxicity across life stage (8 days sublethal assay at 10.
View Article and Find Full Text PDFThe presence of new psychoactive substances (NPS), like metaphedrone (3-MMC), in aquatic environments raises concern about the potential negative effects on ichthyofauna. Therefore, the aim of this study was to evaluate the potential effects of 3-MMC on zebrafish embryonic development, behaviour, and DNA integrity. For that, embryos were exposed during 96 h post-fertilization to 3-MMC (0.
View Article and Find Full Text PDFMDMA (3,4-methylenedioxymethamphetamine) is a chiral psychoactive recreational drug sold in illicit markets as racemate. Studies on the impact of MDMA on aquatic organisms are scarce. While enantioselectivity in toxicity in animals and humans has been reported, none is reported on aquatic organisms.
View Article and Find Full Text PDFVenlafaxine is a chiral antidepressant detected in aquatic compartments. It was recently included in the 3rd Watch List from the European Union. The present study aimed to investigate venlafaxine toxicity effects, targeting possible enantioselective effects, using two aquatic organisms, daphnia (Daphnia magna) and zebrafish (Danio rerio).
View Article and Find Full Text PDFKetamine is a chiral drug used for various clinical purposes but often misused. It is metabolized to norketamine, an active chiral metabolite. Both substances have been detected in environmental matrices, but studies about their enantioselective toxic effects are scarce.
View Article and Find Full Text PDFThe main intent of this work (after the by chance finding, in archived histological slides) is to characterize one previously non-described liver lesion of the Iberian barbel from the Vizela River (Portugal). This ran through a textile and dyeing industrial region. The lesion type was made of groups of foamy cells (presumptive macrophages), which appear either as a "smaller non-nodular form," without a connective tissue capsule and displaying an irregular profile, or as a "bigger nodular form," presenting a thin capsule and a circular profile.
View Article and Find Full Text PDFTransformation of the river catchment and the river bed cause significant changes in the functioning of river ecosystems. The main effects of anthropogenic transformations are hydrological changes, such as lower current velocity or an increase of nutrient content, and higher temperature. Zooplankton reacts rapidly to the new environmental conditions in rivers, increasing its richness and abundance.
View Article and Find Full Text PDFThis study focused on the use of sound playbacks as acoustic deterrents to direct native potamodromous migratory species away from all kind of traps. The effects of two acoustic treatments, a repeated sine sweep up to 2 kHz (sweep-up stimulus) and an intermittent 140 Hz tone, were tested in three fish species native to Iberia: Salmo trutta, Pseudochondrostoma duriense and Luciobarbus bocagei. In contrast with S.
View Article and Find Full Text PDFPurpose: The Miranda donkey (Equus asinus) is an endangeredasinine from Miranda do Douro region, located in the north east of Portugal. We studied the antimicrobial resistance and virulence genes in Escherichia coli and Enterococcus spp. isolates from these animals.
View Article and Find Full Text PDFMany methods in freshwater biomonitoring tend to be restricted to a few levels of biological organization, limiting the potential spectrum of measurable of cause-effect responses to different anthropogenic impacts. We combined distinct organisational levels, covering biological biomarkers (histopathological and biochemical reactions in liver and fish gills), community based bioindicators (fish guilds, invertebrate metrics/traits and chironomid pupal exuviae) and ecosystem functional indicators (decomposition rates) to assess ecological status at designated Water Framework Directive monitoring sites, covering a gradient of human impact across several rivers in northern Portugal. We used Random Forest to rank the variables that contributed more significantly to successfully predict the different classes of ecological status and also to provide specific cut levels to discriminate each WFD class based on reference condition.
View Article and Find Full Text PDFFish are bioindicators of water pollution, and an increased rate of their erythrocyte nuclear morphological abnormalities (ENMAs)-and particularly of erythrocyte micronuclei (EMN)-is used as a genotoxicity biomarker. Despite the potential value of ENMAs and MN, there is scarce information about fish captured in Iberian estuaries. This is the case of the Portuguese estuaries of the Mondego, Douro and Ave, suffering from different levels of environmental stress and where chemical surveys have been disclosing significant amounts of certain pollutants.
View Article and Find Full Text PDFLiver lesions in wild fish have been associated with xenobiotic exposure. Facing reports of pollution in the Douro River estuary (north of Portugal), we have been making field surveys using fishes and targeting histopathological biomarkers of exposure and effect. Herein, we intended to better characterize and report the rate of one poorly understood lesion-hepatocellular fibrillar inclusions (HFI)-found in European flounder (Platichthys flesus).
View Article and Find Full Text PDFAim: To study the effect of nebivolol on liver fibrosis induced by common bile duct ligation (BDL) in rats.
Materials And Methods: After BDL, Wistar rats were divided into three groups (n=24): SO, sham-operated animals; BDL, BDL rats without treatment; BDL+N, BDL rats treated with nebivolol for five weeks. Alanine aminotransferase, aspartate aminotransferase, gamma glutamyltransferase, total bilirubin and albumin levels were assessed.
Many environmental pollutants can exert adverse effects on exposed organisms, including fish, leading to disruption of the endocrine system. Enzymes involved in the sex steroid biosynthesis are potential targets for the toxic action of pollutants. In this context, we investigated the hypothesis that selected estrogenic chemicals-the pharmaceutical estrogen ethinylestradiol (EE2), the phytoestrogen genistein (GEN), and the industrial compound bisphenol A (BPA)-may cause endocrine disruption by directly disturbing steps of fish steroidogenic pathways.
View Article and Find Full Text PDFThe increased pollution in ecosystems reinforces the importance of both chemical monitoring and biological monitoring of streams and rivers, as an effective water quality-based approach to assess aquatic ecosystem health. In this study, gudgeon (Gobio gobio) and mullet (Mugil cephalus) liver histopathology (biomarker) and some macroinvertebrate community indexes and metrics (bioindicator) were used to evaluate the effect of the wastewater treatment plant (WWTP) of Febros (Avintes) in Febros River water quality and ecosystem health. Regarding macroinvertebrate communities, the Belgian Biotic Index (BBI) and Iberian Biological Monitoring Working Party (IBMWP) indexes suggested that Febros water was slightly polluted, even though the worst situation was found downstream the WWTP discharge.
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