RESUMEN
The aim of this study was to evaluate the influence of different stunning methods on the meat quality of Arapaima gigas fillets from fish farming. A total of 48 specimens of A. gigas in the weight class 11.1 to 14.0 kg were investigated; these fish were subjected to different stunning methods for slaughter: ice asphyxia (IA), air asphyxia (AA), electronarcosis (EE) and hypothermia followed by bleeding (HB). Then, data were obtained from the analysis of pH, rigor mortis index (RI), water activity (Aw), instrumental texture (compression strength, firmness and adhesiveness) and blood glucose and via instrumental colourimetry. During the study, for up to 15 days of refrigerated storage, the methods provided pH values below 6.0. A. gigas submitted to EE and HB remained longer in the pre-rigor status. In addition, they expressed lower percentages of Aw. The EE method resulted in better texture assignments in the fillets. The blood glucose values indicated that the fish subjected to EE were less stressed. Concerning instrumental colourimetry, the fillets submitted to EE and HB showed greater luminosity; the fillets subjected to AA showed greater red-green colour intensity, while the fillets subjected to EE showed greater yellow-blue colour intensity. Therefore, the fish did not suffer stress with electronarcosis, and the fillets showed better preservation, juiciness, and tenderness.
RESUMEN
Urbanization and agricultural activities increased environmental contaminants. Integrated analysis of water parameters and bioassays represents an essential approach to evaluating aquatic resource quality. This study aimed to assess water quality by microbiological and physicochemical parameters as well as the toxicological effects of water samples on the Ames test and Caenorhabditis elegans model. Samples were collected during (collection 1) and after (collection 2) pesticide application in the upper (S1), middle (S2), and lower (S3) sections of the Rolante River, southern Brazil. Metals were determined by GFAAS and pesticides by UPLC-MS/MS. Bioassays using the Ames test and the nematode C. elegans were performed. Levels of microbiological parameters, as well as Mn and Cu were higher than the maximum allowed limits established by legislation in collection 2 compared to collection 1. The presence of pesticide was observed in both collections; higher levels were found in collection 1. No mutagenic effect was detected. Significant inhibition of body length of C. elegans was found in collection 1 at S2 (P < 0.001) and S3 (P < 0.001) and in collection 2 at S2 (P = 0.004). Comparing the same sampling site between collections, a significant difference was found between the site of collection (F(3,6)=8.75, P = 0.01) and the time of collection (F(1,2)=28.61, P = 0.03), for the S2 and S3 samples. C. elegans model was useful for assessing surface water quality/toxicity. Results suggest that an integrated analysis for the surface water status could be beneficial for future approaches.
RESUMEN
Water pollution via natural and anthropogenic activities has become a global problem, which can lead to short and long-term impacts on humans' health and the ecosystems. Substantial amounts of individual or mixtures of organic pollutants move into the surface water via point and non-point source contamination. Some of these compounds are known to be toxic and difficult to remove from water sources, thus affecting their quality. Moreover, environmental regulations in high-income countries have become very strict for drinking water treatment over the past decades, especially regarding pesticides. This study aimed to evaluate the efficiency of different residential water treatments to remove 13 pesticides with distinct physicochemical characteristics from the drinking water. Nine water treatments were used: four membrane filters, an activated carbon filter, ultraviolet radiation, reverse osmosis, ion exchange resins, and ozonation. The trial was performed with tap water contaminated with an environmental concentration of 13 pesticides. According to the results, activated carbon and reverse osmosis were 100% efficient for pesticide removal, followed by ion exchange resins and ultraviolet radiation. Membrane filters, in general, showed low efficiency and should, therefore, not be used for this purpose.
Asunto(s)
Agua Potable , Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Humanos , Carbón Orgánico , Ecosistema , Rayos Ultravioleta , Purificación del Agua/métodos , Resinas de Intercambio IónicoRESUMEN
The indiscriminate use of pesticides represents high ecological risk in aquatic systems. Recently, the inclusion of epilithic biofilms as a reactive matrix has shown potential in diagnosing the health of water resources. The objective of this study was to use multiple matrices (water, suspended sediments, and biofilms) to discriminate contamination degrees in catchments with long and recent history of intensive pesticide use and to monitor growing season pesticides transfer to watercourses. Two catchments were monitored: one representative of "modern agriculture" in a subtropical environment, and another representative of recent agricultural expansion over the Pampa Biome in subtropical Brazil. Glyphosate and AMPA were accumulated in the biofilms and were detected at all sites and at all monitoring times, in concentrations ranging from 195 to 7673 µg kg-1 and from 225 to 4180 µg kg-1, respectively. Similarly, the fungicide tebuconazole has always been found in biofilms. The biofilms made it possible to discriminate the long-term history of pesticide use in the catchments and even to identify the influx pulses of pesticides immediately after their application to crops, which was not possible with active water sampling and even with suspended sediment monitoring. It is strongly recommended that, in regions with intensive cultivation of soybeans and other genetically modified crops, the presence of glyphosate and its metabolite AMPA be permanently monitored, a practice still very scarce in the literature.
Asunto(s)
Plaguicidas , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico , Productos Agrícolas , Estaciones del Año , Plantas Modificadas Genéticamente , Biopelículas , Agua , GlifosatoRESUMEN
Spatial-temporal monitoring of the presence of pesticides and pharmaceuticals in water requires rigor in the choice of matrix to be analyzed. The use of matrices, isolated or combined, may better represent the real state of contamination. In this sense, the present work contrasted the effectiveness of using epilithic biofilms with active water sampling and with a passive sampler-POCIS. A watershed representative of South American agriculture was monitored. Nine sites with different rural anthropic pressures (natural forest, intensive use of pesticides, and animal waste), and urban areas without sewage treatment, were monitored. Water and epilithic biofilms were collected during periods of intensive pesticide and animal waste application. After the harvest of the spring/summer crop, a period of low agrochemical input, the presence of pesticides and pharmaceuticals was monitored using the POCIS and epilithic biofilms. The spot water sampling leads to underestimation of the level of contamination of water resources as it does not allow discrimination of different anthropic pressures in rural areas. The use of endogenous epilithic biofilms as a matrix for the analysis of pesticides and pharmaceuticals is a viable and highly recommended alternative to diagnose the health of water sources, especially if associated with the use of POCIS.
Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Plaguicidas/análisis , Brasil , Fuentes de Información , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Biopelículas , Preparaciones Farmacéuticas , RíosRESUMEN
The soybean looper (SBL), Chrysodeixis includens (Walker, [1858]) (Lepidoptera: Noctuidae), is a soybean and cotton pest in South America countries. Field-evolved resistance of SBL to inhibitors of chitin biosynthesis has been reported in Brazil; however, this mode of action is still widely used against SBL. On this basis, we conducted laboratory bioassays to investigate if adjuvants (Nimbus®, TA 35®, Break-Thru® S 240, and Rizospray Extremo®) added to the teflubenzuron spray increase the mortality of SBL strains (resistant, heterozygous, and susceptible to chitin biosynthesis inhibitors). Using chromatography analysis, we also evaluated the amount of teflubenzuron on soybean leaves when applied alone or in combination with adjuvants. In laboratory bioassays, the biological activity of teflubenzuron increased against the susceptible SBL strain when adjuvants were added. In contrast, no relevant effects of adjuvants added to the teflubenzuron spray against heterozygous and resistant SBL larvae were detected. In leaf bioassays, even leaves from the upper third part of the plants containing a significantly higher amount of teflubenzuron (3.4 mg/kg vs 1.7 and 0.6 mg/kg); the mortality of SBL strains was similar when teflubenzuron was applied alone or in mixture with adjuvants. Our findings indicated that adjuvants added to teflubenzuron spray do not provide a substantial increase in the mortality of SBL strains resistant to chitin biosynthesis inhibitors. Therefore, it is necessary to reduce the use of this mode-ofaction insecticide against SBL and to give preference to other insecticides or control tactic.
A lagarta falsa-medideira, Chrysodeixis includens (Walker, [1858]) (Lepidoptera: Noctuidae), é uma praga da soja e do algodão nos países da América do Sul. A resistência de C. includens a inibidores da biossíntese de quitina tem sido relatada no Brasil. Entretanto, esse modo de ação ainda é amplamente utilizado para controle de C. includens. Com base nisso, conduzimos bioensaios em laboratório para investigar se adjuvantes (Nimbus®, TA 35®, Break-Thru® S 240 e Rizospray Extremo®) adicionados à calda inseticida de teflubenzuron aumentam a mortalidade de linhagens de C. includens (resistentes, heterozigotos e suscetíveis a inibidores da biossíntese de quitina). Usando análise cromatográfica, também avaliamos a quantidade de teflubenzuron em folhas de soja quando aplicado isolado ou em combinação com adjuvantes. Em bioensaios de laboratório, a atividade biológica do teflubenzuron aumentou para a linhagem suscetível quando os adjuvantes foram adicionados à calda inseticida. Em contraste, nenhum efeito relevante de adjuvantes adicionados ao teflubenzuron foi detectado para os heterozigotos e resistentes. Em bioensaios de folhas, mesmo naquelas do terço superior das plantas, as quais apresentaram uma maior deposição de teflubenzuron (3,4 mg/kg vs 1,7 e 0,6 mg/kg); a mortalidade das linhagens de C. includens foi semelhante quando o teflubenzuron foi aplicado isolado ou com adjuvantes. Nossos resultados indicam que os adjuvantes adicionados ao teflubenzuron não fornecem um aumento substancial na mortalidade de linhagens de C. includens resistentes aos inibidores da biossíntese de quitina. Portanto, é necessário reduzir o uso desse modo de ação para o manejo de C. includens e dar preferência a outros inseticidas ou tática de controle.
Asunto(s)
Animales , Glycine max , Control de Plagas , InsecticidasRESUMEN
Agriculture activities have increased the concentration of pesticides and metals in the environment. The excessive use of pesticides can generate an environmental impact and contribute to the development of human diseases. This study aimed to determine the presence of pesticides and metals in water samples collected in the Brazilian rural area in two different periods (before and after pesticide application) and to evaluate the alternative bioassays Lactuca sativa, Allium cepa, and Caenorhabditis elegans to monitoring toxicity in human drinking water samples. Eight sites in the rural area were selected and water samples were collected in two different periods of the year (before and after pesticide application). The presence of the pesticides was determinated by ultra-high performance liquid chromatography-tandem mass spectrometry and metals by inductively coupled plasma mass spectrometry. The potential toxicity of the water samples was performed with three different alternatives in vivo models (L. sativa, A. cepa, and C. elegans). Fifty-seven pesticides were analyzed and, according to the results, the most found ones were clomazone, atrazine, tebuconazole, metconazole, pyrimethanil, and carbofuran-3-hydroxide, which is a metabolic degradation product of insecticide carbofuran. The most detected metals were Cu, Cr, Mg, Fe, and Mn. The assays with L. sativa and A. cepa showed alterations in the period after pesticide application, while C. elegans presented changes in both periods compared to the same collection sites. These results indicate that bioassays, especially C. elegans, could be complementary and useful tools for monitoring the toxicity in drinking water samples.
RESUMEN
The aim of the current study is to investigate whether silver catfish (Rhamdia quelen) individuals exposed to commercial formulation of the chlorantraniliprole insecticide used in rice crops present changes in biochemical parameters. Fifty-four (54) silver catfish individuals were distributed in six units per tank (n = 6/repetition; triplicate/treatment) and subjected to the following treatments: T1-control, without insecticide; T2 (0.02 µg/L of insecticide) and T3 (0.20 µg/L of insecticide). Exposure time lasted 24 or 96 h, and it was followed by 96 h recovery in pesticide-free water. Results have indicated biochemical changes in cortisol, glucose, lactate and plasma protein levels, as well as few ionic changes in animals' gills during the exposure and recovery periods. Chlorantraniliprole incidence in water resulted in some biochemical changes in silver catfish specimens' plasma and gills throughout the acute exposure protocol (sub-lethal dose). Thus, chlorantraniliprole insecticide has caused osmoregulatory and/or biochemical imbalance in the investigated species under the herein adopted laboratory conditions; these changes did not get back to normal levels even after specimens were left to recover for 96 h in clean water.
Asunto(s)
Bagres , Insecticidas , Animales , Branquias , Humanos , Insecticidas/toxicidad , ortoaminobenzoatos/toxicidadRESUMEN
Contaminants of emerging concern (CECs) have been a focus of study for years, with investigations revealing the contamination of different environmental matrices (surface water, soil, air, and sediment) by diverse classes of microcontaminants. Understanding the contamination profiles requires identification and risk assessment of the microcontaminants. In the present work, analysis was made of the presence of 3250 compounds in 27 samples from the Conceição River (Rio Grande do Sul State, Brazil), using an SPE-LC-QTOF MS method. In total, 150 microcontaminants (confirmed and suspected) of different classes, especially pesticides and pharmaceuticals, were identified by an initial qualitative analysis. Subsequently, in silico predictions of eight endpoints, using quantitative structure-activity relationship ((Q)SAR) models, were employed to determine the risk of each previously screened microcontaminant. This large amount of (Q)SAR data, frequently with conflicting information in relation to the responses of the different endpoints, makes it difficult to define which microcontaminants should be prioritized for analysis. Therefore, in order to rank the identified microcontaminants by risk assessment, two multi-criteria decision-making (MCDM) ranking techniques (ToxPi and TOPSIS), associated with a weighting method, were performed to establish the order of priority for further quantitative analysis of the most hazardous microcontaminants. The two rankings were statistically similar, especially for the 20 highest priority microcontaminants. Nonetheless, sensitivity tests carried out for the ToxPi and TOPSIS outputs showed higher performance robustness of TOPSIS, compared to ToxPi. This is the first time that such an approach (screening/(Q)SAR/MCDM methods) has been performed in the context of microcontaminant environmental risk evaluation and demonstrated to be an available strategy to help rank the most concern microcontaminants identified in aqueous environment samples.
Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Plaguicidas/análisis , Medición de Riesgo , Ríos , Agua , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidadRESUMEN
Imidacloprid (IMI) is an insecticide used worldwide, a neonicotinoid that could cause toxicity in non-target organisms. Zebrafish (Danio rerio) is a model organism widely used in different fields of research such as behavioral studies, biochemical parameters as well as neurotoxicity research. Here, we investigate whether the exposure to three concentrations (0.15, 15, and 45 µg/L) of IMI for 96 h alters responses in zebrafish. Oxidative stress parameters and acetylcholinesterase activity (AChE) as well as the behavioral responses of locomotion were measured. IMI exposure decreased distance traveled in fish exposed to the 45 µg/L. In the exploratory activity, time spent and transitions to the top area of the water column decreased in fish exposed to all concentrations of IMI. In addition, exposures to 45 and 15 µg/L of IMI decreased episodes of erratic movement in the zebrafish. Exposures to IMI at a concentration of 45 µg/L decreased the time spent in erratic movements and increased the time spent with no movement (i.e., "freezing"). Glutathione S-transferase (GST) activity was increased in the brain of zebrafish exposed for 96 h to concentrations of 0.15 and 45 µg/L. Brain AChE activity was reduced and the levels of carbonyl protein (CP) increased in brain of zebrafish at concentrations of 15 and 45 µg/L. Lipid peroxidation measured by TBARS and, also non-protein thiols (NPSH) did not show any variation in the brain of zebrafish exposed to IMI. Changes in the activity of cholinergic neurotransmitters in the brain tissues of zebrafish indicate IMI toxicity. Exposures of fish over 96 h to IMI at a nominal concentration of 45 µg/L caused more extensive sublethal responses in zebrafish, but this concentration is well above those expected in the aquatic environment. Studies are warranted to evaluate the effects on behavior and biomarker responses in fish exposed over longer periods to IMI at environmentally relevant concentrations.
Asunto(s)
Contaminantes Químicos del Agua , Pez Cebra , Animales , Antioxidantes , Neonicotinoides/toxicidad , Nitrocompuestos , Estrés Oxidativo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidadRESUMEN
The 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. (2) in a laboratory study verify the effects of the most frequently, herbicide, fungicide, and insecticide found in Jacuí river (individualized or in a mixture) on biochemical parameters in different tissues of Oreochromis niloticus. Twenty pesticide residues were detected in superficial water samples, and two of them are banned in Brazilian territory. Atrazine (0.56 µg L-1), azoxystrobin (0.024 µg L-1), and imidacloprid (0.11 µg L-1) were the most frequently herbicide, fungicide, and insecticide, respectively, found in the river and were used in the laboratory assay. O. niloticus exposed to the pesticide mixture exhibited more biochemical effects than individualized exposure groups. This response can be a result of the combined pesticide effects, culminating in an additive or synergistic effect, depending on the biomarker. In individual exposure groups, atrazine presented the most pronounced alterations, followed by azoxystrobin and imidacloprid. Overall, pesticide exposure increased levels of oxidative stress parameters, reduced antioxidant enzyme activities, and induced acetylcholinesterase activity. These findings highlight the threat to aquatic organisms which may be exposed to a miscellaneous of toxic compounds in the environment.
Asunto(s)
Atrazina , Cíclidos , Plaguicidas , Contaminantes Químicos del Agua , Animales , Brasil , Plaguicidas/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidadRESUMEN
Brazil is one of the largest consumers of pesticides in the world, and these chemicals present a high contamination risk for the country's water bodies. The mechanisms of mobilization and transport of pesticides from cropland to river systems are controlled by runoff and erosion processes occurring at the catchment scale. In addition to the excessive use of pesticides, the transport processes of these substances are also accelerated by inadequate soil management and the absence of soil conservation measures at the catchment scale. The current research relied on hydrological monitoring to investigate the transport and persistence of pesticides in response to hydrological dynamics. The study was conducted in the Conceição River watershed where runoff and suspended sediment fluxes are continuously monitored at the outlet. This study area is representative of the grain production system in southern Brazil including the application of large amounts of pesticides combined with extensive runoff and erosion problems. Sample collection in the river for pesticide analysis included the analysis of both water and suspended sediment. The sediment deposit analysis was performed in a single location at 4 depths. Results demonstrate the occurrence of pesticides including simazine, 2,4-D, carbendazim, imidacloprid, tebuconazole, propiconazole, tetraconazole, and trifloxystrobin in water, while glyphosate and AMPA were detected in suspended sediments, and AMPA and carbendazim were found in sediment deposits. The study demonstrated the strong dependence of the mechanisms of pesticide mobilization and transport in the catchment with the intra- and interevent variability of hydro-sedimentary processes. Pesticide detections can be related to several factors, including the magnitude of the rainfall event, the period of pesticide application, or the transport of suspended sediment. All these factors are correlated, and the mechanisms of transportation play an important role in the connections between sink and sources. The results suggest that pesticide monitoring should take into account the runoff and erosion pathways in each particular catchment, and it should especially include the monitoring of major rainfall events for identifying and quantifying the occurrence of pesticides in the environment. The transport of pesticides indicates to be potentiated by intensive pesticide use, the magnitude of rainfall-runoff events, and the absence of runoff control measures (e.g., terracing). These results demonstrate that water and soil conservation techniques should be planned and coordinated at the watershed scale to reduce the connectivity of water and sediment flows from agricultural areas to river systems with the implementation of effective runoff control practices. This will control the mobilization agents (runoff), as well as limit the connection between the sources and the water bodies.
Asunto(s)
Plaguicidas , Agricultura , Brasil , Monitoreo del Ambiente , Sedimentos Geológicos , Plaguicidas/análisisRESUMEN
A wide variety of pharmaceuticals are discharged in water courses on a daily basis due to their incomplete removal from effluent in treatment plants. The aim of the current study was to assess the occurrence, fate and removal of pharmaceuticals from effluent and sludge samples collected in the biggest sanitary sewer plant in Southern Brazil. In total, 13 pharmaceuticals were detected in the influent through UHPLC-MS/M - paracetamol and caffeine recorded the highest concentrations, 137.98 and 35.29 µg L-1, respectively. The treated effluent presented 11 compounds. Antibiotics were the class recording the widest diversity; metronidazole showed the lowest concentration (0.023 µg L-1) and sulfamethoxazole presented the highest concentration (1.374 µg L-1) in influent samples. Seven pharmaceuticals were absorbed by the sludge; among them, one finds caffeine, ciprofloxacin and ofloxacin, which were quantified both in the effluent and in the sludge. On the other hand, doxycycline, fenbendazole, norfloxacin and tetracycline were only detected in sludge samples - their concentrations ranged from 0.026 to 5.034 mg kg-1. Clindamycin, oxytetracycline, sulfathiazole and trimethoprim concentrations increased throughout the treatment. There were high paracetamol and caffeine removal rates (>97%), and it may have happened due to degradation, photodegradation or chemical reaction. Ciprofloxacin and ofloxacin removal rate exceeded 83% mainly due to their sorption by sludge. Finally, the mass balance analysis highlighted high pharmaceutical loads (511.466 g d-1) discharged into recipient waterbodies. This outcome demands broadening the removal of these pharmaceuticals from sewage.
Asunto(s)
Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Purificación del Agua , Brasil , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
Trichlorfon is an organophosphate pesticide used extensively for controlling ectoparasites in aquaculture. Studies have found that trichlorfon caused environmental pollution and severe neurotoxic effects in several freshwater species. Feed additives such as flavonoids may reduce or prevent pesticide-induced toxicity in fish. The aim of the present study was to determine whether acute exposure to trichlorfon impairs behavior and causes oxidative damage in brains of silver catfish (Rhamdia quelen). We also sought to determine whether rutin would be capable of preventing or reducing these effects. Silver catfish were divided into four groups: groups A and C received basal feed, while groups B and D received feed containing 3 mg rutin/kg diet for 21 days. After 21 days, groups C and D were exposed for 48 h to a nominal concentration of 11 mg trichlorfon/L water. Fish exposed to trichlorfon showed significantly longer distances travelled and swimming performances than did unexposed fish. Cerebral levels of reactive oxygen species and lipid peroxidation were significantly higher in fish exposed to trichlorfon than in unexposed fish, while cerebral superoxide dismutase, catalase, glutathione peroxidase, and acetylcholinesterase (AChE) activities were significantly lower. Taken together, our findings suggest that dietary supplementation rutin completely prevented all alterations elicited by trichlorfon, except for cerebral AChE activity; the latter remained significantly lower compared to the unexposed group. In summary, rutin prevents trichlorfon-induced neurotoxicity in silver catfish.
Asunto(s)
Antioxidantes , Bagres/metabolismo , Plaguicidas/toxicidad , Rutina , Triclorfón/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , Acuicultura , Biomarcadores/metabolismo , Encéfalo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Rutina/administración & dosificación , Rutina/farmacologíaRESUMEN
The 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. The fish was exposed to IMI (0.11 µg/L), PRO (0.039 µg/L), or Mix (0.11 µg/L IMI plus 0.039 µg/L PRO) during 96 h. Glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), acetylcholinesterase (AChE) activities were determined. To verify oxidative damage thiobarbituric acid reactive substances (TBARS), protein carbonyl (PC), reactive oxygen species contents (ROS), antioxidant capacity against peroxides (ACAP) were determined in gills, liver, brain and muscle. The results shows that a mixture of these pesticides at environmental concentrations inhibited acetylcholinesterase activity in the brain and induced oxidative damage in all analyzed tissues. These results reinforce the hypothesis that mixture of contaminants present in environment could induce additive or synergistic effects on fish species.
Asunto(s)
Bagres , Plaguicidas , Contaminantes Químicos del Agua , Animales , Catalasa/metabolismo , Bagres/metabolismo , Colinérgicos/metabolismo , Branquias/metabolismo , Glutatión Transferasa/metabolismo , Hígado/metabolismo , Estrés Oxidativo , Plaguicidas/metabolismo , Plaguicidas/toxicidad , Superóxido Dismutasa/metabolismo , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidadRESUMEN
It is well documented today that pesticides, used in crop production, may modulate the immune system of healthy fish. However, there is still only limited information regarding the effects of these anthropogenic stressors in conjunction with natural stressors (pathogens), on the innate immune responses of freshwater fish. Thus, the aim of this investigation was to compare the innate immune response of two groups of fish (Rhamdia quelen), naturally infected with Aeromonas hydrophila, exposed and unexposed to a non-lethal concentration of chlorantraniliprole (CAP) insecticide (0.0 and 1.3 µg/L/24 h). Unhealthy fish exposed to CAP showed significant higher total leukocyte counts and neutrophils percentage compared to non-exposed infected fish). However, the monocytes and eosinophils percentage significantly decreased in fish exposed to CAP. Furthermore, lysozyme activity values measured in plasma, skin mucus, gill and intestine significantly reduced in fish exposed to CAP. The CAP-induced immunomodulation may interfere on the ability of the animal to heal or fight the infection, and possible contribute to the spread of bacterial infection in fish production or environment.
Asunto(s)
Bagres , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Insecticidas , Aeromonas hydrophila , Animales , Infecciones por Bacterias Gramnegativas/veterinaria , Inmunidad Innata , ortoaminobenzoatosRESUMEN
Brazilian 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. Thus, the aim of this study to assess the accumulation of pesticides in muscle of the fish Astyanax jacuhiensis, its biochemical responses, and the presence of pesticides in water. In total, seven pesticides were registered in water from both river sites. Eight pesticides were detected in fish muscle. The biochemical responses showed that brain lipid peroxidation (LPO) and protein carbonyl (PC) in A. jacuhiensis were higher in the summer. Muscle showed the highest LPO levels in the spring and the highest PC in the summer. Liver LPO and PC levels were higher in the spring and summer. In the gills, the PC was higher in the spring and the LPO in the spring and winter. In the brain and in the gills, glutathione-S-transferase activity was high in the summer and autumn. Catalase activity was lower during the winter and spring. Non-protein thiol (NPSH) levels were lower in the brain in the winter and spring. Muscle tissue showed lower NPSH in the winter (site 1). Liver NPSH showed increased levels in liver in the spring and winter (site 2). The biochemical results clearly is related to pesticides and/or to the presence of other contaminants in the water such as metals or domestic sewage. The accumulation of pesticides in fish muscle added evidence that pesticides have been used in the area surrounding the Uruguay River. In conclusion, the biomarkers assayed in the present study could be used in future investigations considering other sampling sites along Uruguay River.
Asunto(s)
Characidae/fisiología , Monitoreo del Ambiente , Plaguicidas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Biomarcadores/metabolismo , Brasil , Characidae/metabolismo , Characiformes/metabolismo , Characiformes/fisiología , Ecosistema , Branquias/metabolismo , Peroxidación de Lípido , Metales/metabolismo , Plaguicidas/análisis , Ríos/química , Estaciones del Año , Contaminantes Químicos del Agua/análisisRESUMEN
Monitoring of triphenyltin (TPhT) in the environment, particularly to control its misuse in agriculture, is of great importance because of its high toxicity. In this work, methods for determination of TPhT residues in surface water and soil samples by liquid chromatography with tandem mass spectrometry (LC-MS/MS) were developed and validated. Different sample volumes and pH and elution solvent types and volumes were evaluated for solid phase extraction (SPE) of TPhT in surface water samples. The optimized conditions were 500 mg sorbent Strata C18-E, 100 mL of the sample, pH adjusted to 9.0 and 1 mL of methanol containing acetic acid as the eluent. For a 10 g soil sample, the extraction was established using a modified QuEChERS method with 10 mL of acidified acetonitrile followed by a clean-up step by dispersive solid phase extraction (dSPE) with C18. A full factorial 23 design of experiments was applied to optimize the sample preparation method for soil samples. Practical method limits of quantification were 0.1 µg L-1 and 10 µg kg-1 for surface water and soil samples, respectively. Satisfactory accuracy, with recoveries from 86 to 107% for surface water and 72 to 87% for soil samples, as well as good precision, with an overall relative standard deviation (RSD) from 3 to 8% was observed. The validated methods were applied to real samples and some residues of TPhT were found, especially in soil samples (30 to 190 mg kg-1), indicating the suitability for routine analysis.
RESUMEN
A miniaturized sample preparation method was developed and validated for the multiresidue determination of 97 pesticides in wine samples. The proposed extraction procedure is based on the QuEChERS acetate method with dispersive solid phase extraction (d-SPE) for the clean-up step. Ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) was used for determination. The extraction and clean-up steps were evaluated to obtain the best conditions for the selected pesticides. Miniaturization of the sample preparation step provided a reduction in the consumption of samples and chemicals. The method limit of quantification was between 10 and 20 µg L-1. Trueness results, obtained by recovery assays at the spike levels 10, 20, 50 and 100 µg L-1, ranged from 70 to 120% with precision in terms of relative standard deviations (RSD) ≤ 20%. The method was successfully applied for the analysis of wine samples and different pesticides were found at concentrations from 14 to 55 µg L-1.
Asunto(s)
Residuos de Plaguicidas , Vino , Cromatografía Líquida de Alta Presión , Residuos de Plaguicidas/análisis , Extracción en Fase Sólida , Espectrometría de Masas en Tándem , Vino/análisisRESUMEN
Freshwater ecosystems are constantly threatened by the advance of agricultural activities. Abiotic variables (such as temperature, ammonia, and nitrite) and contaminants (e.g. pesticides) can potentially interact, increasing metabolism and the absorption of toxic substances, which can alter the ability of organisms to establish adequate stress responses. This study aimed to verify which pesticides were most frequently found and in the greatest quantities in low-order streams, and whether the combination of these pesticides with the abiotic variables altered the biological metabolism of aeglids. These freshwater crustaceans are important shredders that inhabit low-order streams and are sensitive to disturbances and/or abrupt environmental variations. The animals were exposed in situ in four streams (reference site and sites 1, 2, and 3). The reference site is a preserved stream with no apparent anthropogenic interference where aeglids still occur, while the other sites no longer exhibit populations of these animals and are influenced by agricultural activities. The exposure was performed bimonthly from November 2017 to September 2018 and lasted 96 h. Measured abiotic data and water samples were collected through all days of exposure. The analyzed biochemical parameters were acetylcholinesterase activity in muscle; and glutathione S-transferase, lipid peroxidation, protein carbonylation, non-protein thiols, antioxidant capacity against peroxides, and reactive oxygen species (ROS) in muscle, gills, and hepatopancreas. We found 24 active principles of pesticides, the most frequently being clomazone, atrazine, and propoxur. Bentazone was present at the highest amounts. The parameters evaluated in this study, including biochemical biomarkers and abiotic factors measured from the water, provided a separation of the months as a function of environmental conditions. There was a difference in activity and biomarker levels throughout the year within the same site and in some months between sites. The greater concentration or variety of pesticides associated with extreme abiotic (very high temperatures) data generated increased oxidative stress, with high levels of protein damage and considerable lipid damage in all tissues, as well as elevation in ROS, even with high levels of antioxidant capacity and non-protein thiols. With these data, we intend to warn about the risks of exposure to these environmental conditions by trying to contribute to the preservation of limnic fauna, especially aeglid crabs, because most species are under some degree of threat.