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1.
Environ Geochem Health ; 45(5): 2415-2434, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35986856

RESUMO

Spatial distribution linked to geostatistical techniques contributes to sum up information into an easier-to-comprehend knowledge. This study compares copper spatial distribution in surface sediments and subsequent categorization according to its toxicological potential in two reservoirs, Rio Grande (RG) and Itupararanga (ITU) (São Paulo-Brazil), where copper sulfate is applied and not applied, respectively. Sediments from 47 sites in RG and 52 sites in ITU were collected, and then, copper concentrations were interpolated using geostatistical techniques (kriging). The resulting sediment distributions were classified in categories based on sediment quality guides: threshold effect level and probable effect level; regional reference values (RRVs) and enrichment factor (EF). Copper presented a heterogenic distribution and higher concentrations in RG (2283.00 ± 1308.75 mg/kg) especially on the upstream downstream, associated with algicide application as well as the sediment grain size, contrary to ITU (21.81 ± 8.28 mg/kg) where a no-clear pattern of distribution was observed. Sediments in RG are predominantly categorized as "Very Bad", whereas sediments in ITU are mainly categorized as "Good", showing values higher than RRV. The classification is supported by the EF categorization, which in RG is primarily categorized as "Very High" contrasting to ITU classified as "Absent/Very Low". Copper total stock in superficial sediment estimated for RG is 4515.35 Ton of Cu and for ITU is 27.45 Ton of Cu.


Assuntos
Sulfato de Cobre , Poluentes Químicos da Água , Sulfato de Cobre/toxicidade , Cobre/toxicidade , Cobre/análise , Ecotoxicologia , Sedimentos Geológicos , Brasil , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
2.
Environ Sci Pollut Res Int ; 29(4): 6294-6305, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34449024

RESUMO

Copper sulfate (CuSO4) is widely used in agriculture as a pesticide and foliar fertilizer. However, the possible environmental risks associated with CuSO4 use, particularly related to pollinating insects, have been poorly studied. In this study, we evaluated both lethal and sublethal effects of CuSO4 on the stingless bee Partamona helleri. Foragers were orally exposed to five concentrations of CuSO4 (5000, 1666.7, 554.2, 183.4, 58.4 µg mL-1), and the concentration killing 50% (LC50) was estimated. This concentration (142.95 µg mL-1) was subsequently used in behavioral, midgut morphology, and antioxidant activity analyses. Bee mortality increased with the ingestion of increasing concentrations of CuSO4. Ingestion at the estimated LC50 resulted in altered walking behavior and damage to the midgut epithelium and peritrophic matrix of bees. Furthermore, the LC50 increased the catalase or superoxide dismutase activities and levels of the lipid peroxidation biomarker malondialdehyde. Furthermore, the in situ detection of caspase-3 and LC3, proteins related to apoptosis and autophagy, respectively, revealed that these processes are intensified in the midgut of treated bees. These data show that the ingestion of CuSO4 can have considerable sublethal effects on the walking behavior and midgut of stingless bees, and therefore could pose potential risks to pollinators including native bees. Graphical abstract.


Assuntos
Antioxidantes , Sulfato de Cobre , Animais , Abelhas , Sulfato de Cobre/toxicidade , Sistema Digestório , Fertilizantes , Dose Letal Mediana
3.
Environ Sci Pollut Res Int ; 28(33): 45317-45334, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33860426

RESUMO

The increasing use and disposal of plastics has become a persistent problem in the marine environment, calling for studies that refer to realistic scenarios to understand their effects on biota. Particularly, the understanding about the effects of co-exposure with nanoplastic particles and metals on aquatic organisms is still limited. The present work aimed to investigate the acute toxicity of amino-functionalized polystyrene nanoparticles (PS-NH2; 50 nm) as proxy for nanoplastics on brine shrimp Artemia franciscana larvae under different culture conditions and at different stages of development, as well as the combined effect with two reference toxicants - potassium dichromate (K2Cr2O7) and copper sulfate (CuSO4). Nauplii (instar II or III larval stages) were exposed to different concentrations of PS-NH2 (0.005 to 5 µg mL-1) for up to 48 h, with or without agitation in order to mimic a more realistic environmental scenario. Larval mobility and PS-NH2 accumulation were monitored under microscopy. PS-NH2 alone showed toxicity only at the highest concentration tested (5 µg mL-1) regardless the incubation method used (61.2 + 3.1% and 65.0 + 4.5% with and without agitation, respectively). Moreover, instar III stage was the most sensitive to PS-NH2 exposure (38.2% immobility in 24 h of exposure; 5 µg mL-1). Evidence of PS-NH2 retention in the gastrointestinal tract in a concentration- and time-dependent manner was also obtained. Mixtures of PS-NH2 (0.005 and 5 µg mL-1) with different concentrations of K2Cr2O7 increased the immobilization rate of the larvae after 48 h of exposure, when compared to the K2Cr2O7 alone. Similar results were observed for CuSO4 in the co-exposure conditions at different concentrations. However, exposing nauplii to a mixture of PS-NH2 (0.005 µg mL-1) and CuSO4 decreased immobilization rate, in comparison to the group exposed to CuSO4 alone. The present work highlights the potential risk posed by nanoplastics to zooplanktonic species through their interaction with other toxicants.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Artemia , Sulfato de Cobre/toxicidade , Larva , Poliestirenos , Dicromato de Potássio/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
4.
Fish Physiol Biochem ; 46(6): 2377-2387, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33025302

RESUMO

Rapid industrialization results in the production of large quantities of waste that are commonly discharged into water bodies, leading to the damage of the aquatic ecosystem and freshwater organisms. Copper (Cu) can induce oxidative damage in fish muscle, the main fish portion that is consumed by humans. However, the responses of the Amazon fish Cichlasoma amazonarum and its capacity to withstand acute Cu concentrations found in Amazon water around mines remain unknown. Thus, the aim of this study was to evaluate whether exposure to Cu causes muscle oxidative stress and/or oxidative damage and impairs the fillet fatty acid profile of C. amazonarum acutely exposed to Cu found in Amazon waters around mines. Muscle reactive oxygen species and protein carbonylation levels were significantly higher in fish exposed to 1500 µg/L Cu compared with the control group, while muscle lipid peroxidation levels were significantly higher in fish exposed to 500, 750, and 1500 µg/L Cu compared with control group. Muscle antioxidant capacity against peroxyl radical's levels and glutathione peroxidase activity were significantly lower in fish exposed to 1500 µg/L Cu compared with the control group, while muscle superoxide dismutase activity was significantly lower in fish exposed to 750 and 1500 µg/L Cu compared with control group. The total content of saturated fatty acids was significantly higher in fish exposed to 1500 µg/L Cu compared with the control group, while the total content of monounsaturated fatty acids and sum of n3 fatty acids were significantly lower in fish exposed to 1500 µg/L Cu compared with control group. No significant difference was observed regarding muscle catalase, glutathione S-transferase, and glutathione reductase activities. Based on these lines of evidence, the results of this comprehensive study agree with the initial hypothesis that the exposure to Cu found in Amazon water around mines induces oxidative damage and inhibits enzymatic and non-enzymatic antioxidant response in the muscle of C. amazonarum exposed to high Cu levels. Moreover, the impairment of the fillet fatty acid profile appears to be mediated by oxidative damage, representing a negative impact on fish health.


Assuntos
Ciclídeos/metabolismo , Sulfato de Cobre/toxicidade , Ácidos Graxos/metabolismo , Músculos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Proteínas de Peixes/metabolismo , Glutationa Transferase/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Músculos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo
5.
Chemosphere ; 234: 187-195, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31212205

RESUMO

The exposure of bees to agrochemicals during foraging and feeding has been associated with their population decline. Sublethal exposure to agrochemicals can affect behavior and the microbiota. Gut microbiota is associated with insect nutritional health, immunocompetence, and is essential for neutralizing the damage caused by pathogens and xenobiotics. Research on the effect of the bioinsecticides and fertilizers on the microbiota of bees remains neglected. In this study, we assessed the sublethal effect of both bioinsecticide spinosad and the fertilizer copper sulfate (CuSO4) on the behavior and gut microbiota in forager adults of the stingless bee Partamona helleri (Friese), which is an important pollinator in the Neotropical region. Behavioral assays and gut microbiota profiles were assessed on bees orally exposed to estimated LC5 values for spinosad and CuSO4. The microbiota were characterized through 16S rRNA gene target sequencing. Acute and oral sublethal exposure to spinosad and CuSO4 did not affect the overall activity, flight take-off, and food consumption. However, CuSO4 decreased bee respiration rate and copper accumulated in exposed bees. Exposure to spinosad increased the proportional abundance of the genus Gilliamella, but CuSO4 did not alter the composition of the gut microbiota. In conclusion, sublethal exposure to CuSO4 induces changes in respiration, and spinosad changes the abundance of gut microorganisms of P. helleri.


Assuntos
Bactérias/isolamento & purificação , Abelhas/efeitos dos fármacos , Abelhas/microbiologia , Fertilizantes/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/microbiologia , Macrolídeos/toxicidade , Animais , Bactérias/classificação , Bactérias/genética , Abelhas/crescimento & desenvolvimento , Comportamento Animal/efeitos dos fármacos , Sulfato de Cobre/toxicidade , Combinação de Medicamentos , Dose Letal Mediana , RNA Ribossômico 16S/genética , Respiração
7.
Biol Trace Elem Res ; 189(2): 574-585, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30178145

RESUMO

Copper is a transition metal that exists in different chemical forms (e.g., Cu2+,Cu+, and Cu0) and at high concentrations it is toxic. Here, we investigated the Cu2+-induced toxicity in Drosophila melanogaster, evaluating the survival, locomotion, and the activity of acetylcholinesterase (AChE) and glutathione S-transferase (GST) enzymes. Flies were exposed to Cu2+(0.1-1 mmol CuSO4/kg of diet or approximately 0.1-1 mM Cu2+) and allowed to mate during 24 h. GST and AChE enzymes were evaluated in the larvae and in the head and the body (thorax + abdomen) of the adult male and females flies. The total number of adult females (0.4-1 mM) and males (0.75 and 1 mM) was decreased by CuSO4. The climbing ability was hampered in flies exposed to 1 mM Cu2+. In larvae, Cu2+(0.4-1 mM) increased AChE activity (P < 0.002). In males' heads, 0.4 mM Cu2+ increased the AChE activity (P < 0.01). In adults' bodies, Cu2+inhibited the activity in both sexes, but with greater effectiveness in males (0.1 to 1 mM) than in females (1 mM). Regarding GST activity, 0.1 mM Cu2+increased, but 1 mM decrease GST in larvae. In the head of flies, Cu2+decreased the GST activity at intermediate (0.4 mM) and increased GST at the highest concentration (1 mM) in males. In the bodies, the effect of Cu2+was similar. In conclusion, Cu2+exposure in D. melanogaster disrupted locomotion and enzymatic parameters that can be related to changes in AChE and in the detoxifying GST enzyme.


Assuntos
Sulfato de Cobre/toxicidade , Acetilcolinesterase/metabolismo , Animais , Catalase/metabolismo , Cobre/metabolismo , Drosophila melanogaster , Ativação Enzimática/efeitos dos fármacos , Feminino , Glutationa Transferase/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos
8.
World J Microbiol Biotechnol ; 34(8): 105, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-29971504

RESUMO

Vale dos Vinhedos appellation of origin has a very recent history as industrial wine making region. In this study we investigated the genetic and phenotypic variability of Saccharomyces cerevisiae strains isolated from South-Brazilian vineyards in order to evaluate strain fermentation aptitude and copper and sulphites tolerance. Merlot grape bunches were collected from three vineyards and yeast isolation was performed after single bunch fermentation. High genotypic variability was found and most of the genotypes revealed to be vine-specific. No industrial strain dissemination was present in the sampled vineyards, although it has been wildly reported in traditional winemaking countries. From the phenotypic traits analysis these Brazilian native strains showed good fermentation performances, good tolerance to sulphites and, in particular, a high copper tolerance level. Copper is the most important metal in the formulation of fungicides against downy mildew (Plasmopara viticola), one of the most harmful disease of the vines, and other fungal pests. The high tolerance to copper suggests an environmental adaptation to the strong use of copper-based fungicides, requested by the wet subtropical climate.


Assuntos
Variação Genética , Genótipo , Fenótipo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia , Agricultura , Brasil , Cobre/toxicidade , Sulfato de Cobre/toxicidade , DNA Fúngico/genética , Tolerância a Medicamentos , Fazendas , Fermentação , Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Genes Fúngicos , Mapeamento Geográfico , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/toxicidade , Cinética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/isolamento & purificação , Dióxido de Enxofre/toxicidade , Vitis/química , Vitis/microbiologia , Vinho/microbiologia
9.
Bull Environ Contam Toxicol ; 93(4): 442-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25168694

RESUMO

The sensitivity of Danio rerio to three chemicals was compared at two growth stages [larval (10 ± 2 after hatching) and post-larval (60 ± 4 days after hatching)] based on acute toxicity tests. Thirty-nine 48 h acute toxicity tests were performed with the substances CuSO4, NaCl and KCl. The 48 h LC50 values at the two growth stages were compared by independent samples t-tests. The results showed a clear decrease in sensitivity when post-larval organisms were used. Since acute toxicity test methods for D. rerio that recommend using post-larval stage fish do not represent the most sensitive stage of the test organism, our study suggests a revision of the methods to use larval fish.


Assuntos
Sulfato de Cobre/toxicidade , Modelos Animais , Cloreto de Potássio/toxicidade , Cloreto de Sódio/toxicidade , Testes de Toxicidade Aguda/métodos , Peixe-Zebra/metabolismo , Fatores Etários , Animais , Larva/efeitos dos fármacos , Dose Letal Mediana
10.
J Appl Toxicol ; 34(2): 214-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23401233

RESUMO

Zebrafish (Danio rerio) is increasingly employed for evaluating toxicity and drug discovery assays. Commonly experimental approaches for biotoxicity assessment are based on visual inspection or video recording. However, these techniques are limited for large-scale assays, as they demand either a time-consuming detailed inspection of the animals or intensive computing resources in order to analyze a considerable amount of screenshots. Recently, we have developed a simple methodology for tracking the locomotor activity of small animals cultured in microtiter plates. In this work, we implemented this automatic methodology, based on infrared (IR) microbeam scattering, for measuring behavioral activity in zebrafish larvae. We determined the appropriate culture conditions, number of animals and stage of development to get robust results. Furthermore, we validated this methodology as a rapid test for evaluating toxicity. By measuring the effects of reference compounds on larvae activity, we were able to estimate the concentration that could cause a 50% decrease in activity events values (AEC50), showing a strong linear correlation (R² = 0.91) with the LC50 values obtained with the standard DarT test. The toxicity order of the measured compounds was CuSO4 > 2,4-dinitrophenol > 3,4-dichloroaniline > SDS > sodium benzoate > EDTA > K2CrO4 ; regarding solvents, EtOH ≈ DMSO. In this study, we demonstrate that global swimming behavior could be a simple readout for toxicity, easy to scale-up in automated experiments. This approach is potentially applicable for fast ecotoxicity assays and whole-organism high-throughput compound screening, reducing the time and money required to evaluate unknown samples and to identify leading pharmaceutical compounds.


Assuntos
Ecotoxicologia/métodos , Atividade Motora/efeitos dos fármacos , Espalhamento de Radiação , Testes de Toxicidade , 2,4-Dinitrofenol/toxicidade , Compostos de Anilina , Animais , Cromatos/toxicidade , Sulfato de Cobre/toxicidade , Relação Dose-Resposta a Droga , Ácido Edético/toxicidade , Feminino , Larva/efeitos dos fármacos , Dose Letal Mediana , Masculino , Compostos de Potássio/toxicidade , Reprodutibilidade dos Testes , Benzoato de Sódio/toxicidade , Dodecilsulfato de Sódio/toxicidade , Peixe-Zebra
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