RESUMO
Aqueous film-forming foams (AFFF), containing perfluorinated surfactants, can reach the environment. The objective of this study was to determine the ecotoxicity of AFFF, according to the type of fire to be fought (A1: 1.05 g.L- 1, A2: 3.15 g.L- 1 and A3: 6.30 g.L- 1), to bioindicators of different trophic levels. For Artemia salina a toxic effect was observed at sample A1 (at concentrations of 100%), A2 (at concentrations above 25%) and A3 (at concentrations above 12.5%). For Lactuca sativa all samples affected the number of germinated seeds, speed and percentage of germination and root length. To the Eisenia fetida earthworm, samples A2 and A3 were considered toxic due to the percent avoidance being 70% and 100%, respectively. In Macaca mullata renal cell culture test, none of the samples were toxic by the MTT test. Therefore, it is necessary to develop methods for the safe use of AFFF by professionals.
Assuntos
Artemia , Tensoativos , Poluentes Químicos da Água , Animais , Tensoativos/toxicidade , Poluentes Químicos da Água/toxicidade , Artemia/efeitos dos fármacos , Oligoquetos/efeitos dos fármacos , Incêndios , Lactuca/efeitos dos fármacos , Lactuca/crescimento & desenvolvimento , Fluorocarbonos/toxicidade , Testes de ToxicidadeRESUMO
The increased production and expanding demand for cellulosic products have required companies to provide solutions for the proper disposal of generated residues without compromising soil quality. In this context, the current research aimed at evaluating the ecotoxicological impacts of dregs application in subtropical soils. The experiments were carried out with the earthworm Eisenia andrei, the springtail Folsomia candida, and the potworm Enchytraeus crypticus in two subtropical soils (Neosol and Cambisol) collected in the southern region of Brazil. The considerable differences in texture and organic matter content motivated the choosing of these soils. The reproductive rate of all organisms was influenced, with varying EC50 values depending on the soil type. However, more pronounced effects were observed for Neosol. The springtail F. candida proved to be the most sensitive to contamination (EC50 = 5.8 g kg-1 for Neosol and 48.5 g kg-1 for Cambisol), followed by the earthworm E. andrei (EC50 = 62.4 g kg-1 for Neosol and 129.5 g kg-1 for Cambisol) and the potworm E. crypticus (EC50 = 67.2 g kg-1 for Neosol and 230.4 g kg-1 for Cambisol). As a result, while dregs can be used to correct soil acidity, they have been shown to have negative effects on important organisms responsible for functions critical to maintaining ecosystem quality.
Assuntos
Oligoquetos , Papel , Poluentes do Solo , Solo , Animais , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Solo/química , Brasil , Resíduos Industriais , Ecotoxicologia , Monitoramento AmbientalRESUMO
Copper is a trace element in plants and animals whose importance can be understood due to its role in different essential metabolic processes. Anthropogenic activities such as agriculture and mining are potential sources of pollution due to the emission of copper into the environment. Brazilian legislation ties soil quality to guideline values, among which the Prevention Value indicates the critical environmental limit for trace elements. The aim of this study was to obtain PVs for copper for two subtropical soils (Cambisol and Nitisol), given that the pedological richness was not considered when deriving the PVs contained in the federal normative. Reproduction assays followed ISO guidelines with the earthworm species Eisenia andrei and Perionyx excavatus, the enchytraeids Enchytraeus crypticus and Enchytraeus bigeminus and the springtails Folsomia candida and Proisotoma minuta. Results showed that the sensitivity of the organisms was greater in Cambisol. The most sensitive species were the earthworms, especially Perionyx excavatus (EC50 = 67.83 in Cambisol; EC50 = 264.96 in Nitisol). The springtails, on the other hand, were the least sensitive to contamination. These findings reinforce the need to include organisms from different ecological groups in ecotoxicological assessments. It was also observed that the PV adopted in federal legislation (= 60 mg kg-1) is in fact protective for the species and soils we evaluated, since the PVs we obtained based on the EC50 were 346.74 mg kg-1 in Nitisol and 134.05 mg kg-1 in Cambisol. It is important to note that our results do not exclude the need for evaluations with other subtropical soils, given the influence of their properties on the toxicity and bioavailability of copper to soil organisms.
Assuntos
Cobre , Oligoquetos , Poluentes do Solo , Solo , Solo/química , Animais , Brasil , Monitoramento AmbientalRESUMO
The massive influx of Sargassum natans and S. fluitans to the shores of the Mexican Caribbean has raised concerns regarding their potential impact on soil quality and health in coastal and agroecosystems. The effects of Sargassum accumulation remain largely unexplored. This study aimed to assess the impact of Sargassum on soil ecosystems by examining the behavior and survival of the epigean earthworm Eisenia fetida. The earthworm was exposed to varying concentrations of Sargassum (0, 25, 50, 75, and 100%) in two toxicological tests. Results from the avoidance test demonstrated that E. fetida exhibited strong aversion (> 80%) to a diet containing 100% Sargassum. Conversely, the acute test revealed minimal mortality, but growth decreased with increasing Sargassum concentrations. These findings can serve as early warning bioindicators for assessing the environmental risk posed by Sargassum in soil ecosystems.
Assuntos
Oligoquetos , Sargassum , Poluentes do Solo , Animais , Oligoquetos/fisiologia , Oligoquetos/efeitos dos fármacos , Sargassum/fisiologia , Poluentes do Solo/toxicidade , Solo/química , Comportamento Animal/efeitos dos fármacos , México , Monitoramento AmbientalRESUMO
The aim of this study was to formulate novel biomixtures with the ability to dissipate globally used pesticides. For this, an effective stabilization of two wastes, poultry litter and activated sewage sludge, was achieved through a combination of composting and vermicomposting, with the aid of the earthworm Eisenia fetida. Hence, two different mixtures were prepared combining the wastes with and without the addition of sewage sludge, and their physicochemical and microbiological characterization was examined during both processes. Earthworms reproduction was promoted by more than fourteen times the initial number of individuals introduced. This step made it possible to obtain substrates rich in organic matter, stable and non-pathogenic. The resulting vermicomposted substrates (V-C1 and V-C2) were used to produce two different biomixtures with wheat stubble (WS) and soil (S): SWSV-C1 and SWSV-C2, and they were tested for the remediation of a solution of five pesticides (2,4-D, cypermethrin, imidacloprid, acetochlor and dimethoate) in a 119-days assay. Comparisons were made with a WS-only biomixture (SWS) and a soil control. All biomixtures were more successful in dissipating the pesticides than soil; 2,4-D, dimethoate, and acetochlor degradation reached more than 99% in the three biomixtures after 28-56 days of assay. Biomixtures containing either vermicomposts acted faster than SWS, particularly for 2,4-D, dimethoate and cypermethrin. The total microbial activity was found to be higher in the two biomixtures containing vermicompost, which can be linked to their enhanced performance in the degradation of pesticides. Although the germination of Lactuca sativa proved that neither of the three spent biomixtures were phytotoxic at the end (germination index >60%), only SWSV-C1 and SWSV-C2 proved to be safe for the survival of E. fetida. This work confirms that vermicompost improves the success of biomixtures, not only in terms of pesticide removal, but also providing non-toxic spent biomixtures.
Assuntos
Compostagem , Oligoquetos , Praguicidas , Aves Domésticas , Esgotos , Poluentes Químicos da Água , Animais , Esgotos/química , Esgotos/microbiologia , Biodegradação Ambiental , Solo/química , Recuperação e Remediação Ambiental/métodosRESUMO
The aim of this work was to stabilize excess sludge (ES) coming from a wastewater treatment plant (WWTP) by vermistabilization and to evaluate ecotoxicological effects over the earthworm species Eisenia fetida. Three mixtures were made up in triplicate using different volume ratios of ES and soil (S) (100% ES, 70:30% ES:S and 30:70% ES:S in wet weight basis). Earthworms were added in order to compare vermicomposting vs. natural stabilization. The mixtures were monitored over 130 days through physical, chemical, pathological and biological analysis, following quality standards depicted in the US EPA 40 CFR Part 503, local regulations and background studies. Histopathological samples were processed as biomarkers of acute and chronic toxicity on earthworms, and germination assays were performed at the end of the experiment to assess phytotoxicity. In terms of pathogen depletion comparing initial and final values from each treatment, the mixtures with higher ES proportions (70 and 100%) with earthworms were the most efficient ones registering 64.8 and 75.5% of reduction of fecal coliforms (FC) respectively, while the lowest ES proportion with earthworms (30%) showed 54.7%. Final pathogens content in all the treatments with earthworms were significantly lower (ranged from 1360 to 1760 MPN g total solids-1) than the values registered in treatments without earthworms (ranged from 2400 to 4000 MPN g total solids-1) (p < 0.05). However, none of the treatments attained class A categorization (FC ≤ 1000 MPN g total solids-1) in terms of FC. Also, values of mean cocoon production and hatched juveniles along time were significantly higher in the treatments with 100 and 70% ES (p < 0.05), while the higher mean adult biomass was detected in the treatment with 30% ES. Volatile solids decrease ranged between 8.45 and 22.34% in treatments with earthworms and all values of specific oxygen uptake rate were below 1.5 mg O2 h -1 g total solids -1. There were not negative effects over behavior or reproduction of E. fetida adults, nor the presence of external and internal injuries. Final products from mixtures with earthworms presented a humus-like structure, were odorless and reached maturity values -presenting no phytotoxicity-with significant differences between germination index values of treatments with and without earthworms (p < 0.05). Vermistabilization is a successful eco-technology to sanitize excess sludge, acquiring an added-value material and contributing to its revalorization as organic amendments or fertilizers in soils within the circular economy framework and the United Nations' Sustainability Development Goals.
Assuntos
Oligoquetos , Esgotos , Animais , Oligoquetos/efeitos dos fármacos , Compostagem , Solo/químicaRESUMO
Soil contamination by antibiotics is a global issue of great concern that contributes to the rise of bacterial antibiotic resistance and can have toxic effects on non-target organisms. This study evaluated the variations of molecular, cellular, and histological parameters in Eisenia fetida earthworms exposed to sulfamethazine (SMZ) and tetracycline (TC), two antibiotics commonly found in agricultural soils. The earthworms were exposed for 14 days to a series of concentrations (0, 10, 100, and 1000 mg/kg) of both antibiotics. SMZ and TC did not affect the survival of E. fetida, however, other effects at different levels of biological complexity were detected. The two highest concentrations of SMZ reduced the viability of coelomocytes. At the highest TC concentration, there was a noticeable decline in cell viability, acetylcholinesterase activity (neurotoxicity), and the relative presence of mucopolysaccharides in the epidermis (mucous production). Glutathione S-transferase activity decreased in all TC treatments and at the highest SMZ concentration. However, levels of malondialdehyde and protein carbonyls did not change, suggesting an absence of oxidative stress. Tetracycline was neurotoxic to E. fetida and changed the integrity of the epidermis. Both antibiotics altered the intestinal microbiota of E. fetida, leading to a reduction in the relative abundance of bacteria from the phyla Proteobacteria and Bacteroidetes, while causing an increase in the phylum Actinobacteroidota. All observed changes indicate that both SMZ and TC can disrupt the earthworms' immune system and gut microbiome, while fostering the growth of bacteria that harbour antibiotic resistance genes. Finally, both antibiotics exerted additional metabolic and physiological effects that increased the vulnerability of E. fetida to pathogens.
Assuntos
Antibacterianos , Oligoquetos , Poluentes do Solo , Sulfametazina , Tetraciclina , Oligoquetos/efeitos dos fármacos , Animais , Sulfametazina/toxicidade , Tetraciclina/toxicidade , Poluentes do Solo/toxicidade , Antibacterianos/toxicidadeRESUMO
Biobeds are presented as an alternative for good pesticide wastewater management on farms. This work proposes a new test for in-situ biomonitoring of pesticide detoxification in biobeds. It is based on the assessment of visually appreciable injuries to Eisenia fetida. The severity of the injury to each exposed individual is assessed from the morphological changes observed in comparison with the patterns established in seven categories and, an injury index is calculated. A linear relationship between the proposed injury index and the pesticide concentration was determined for each pesticide sprayed individually in the biomixture. The five pesticides used were atrazine, prometryn, clethodim, haloxyfop-P-methyl and dicamba. In addition, a multiple linear regression model (i.e., a multivariate response surface) was fitted, which showed a good generalization capacity. The sensitivity range of the injury test was tested from 0.01 to 630 mg kg-1 as the total pesticide concentration. This index is then used to monitor the detoxification of these pesticides in a biomixture (composed of wheat stubble, river waste, and soil, 50:25:25% by volume) over 210 days. The results are compared with standardized tests (Eisenia fetida avoidance test and Lactuca sativa seed germination test) carried out on the same biomixture. The results are also compared with data on the removal of pesticides. The injury test showed a better correlation with the removal of pesticides than the avoidance test and seed germination test. This simple and inexpensive test has proved to be useful for decontamination in-situ monitoring in biobeds.
Assuntos
Monitoramento Biológico , Oligoquetos , Praguicidas , Praguicidas/análise , Praguicidas/metabolismo , Oligoquetos/metabolismo , Monitoramento Biológico/métodos , Animais , Atrazina/toxicidade , Atrazina/análise , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Monitoramento Ambiental/métodos , Águas Residuárias/química , Prometrina/toxicidade , DicambaRESUMO
This study characterized a nanosupplement based on coenzyme Q10 containing guarana (Paullinia cupana) and Brazil nuts oil (Bertholetia excelsa) (G-Nut). Determined cytotoxic and oxi-immunomodulatory effects on human peripheral blood mononuclear cells (PBMCs) and its effect on mortality of red Californian earthworms (Eisenia fetida) and on the immune efficiency of its coelomocytes immune by in vitro exposure to yeast dead microorganism. The cytotoxic and immunomodulatory effects of G-Nut and the GN-Free extract (0.25-3 mg/mL) were determined in PBMC cultures. Apoptotic, oxidative, and inflammatory markers were determined using biochemical, immunological, and molecular protocols. The effects of G-Nut and GN-Free extracts on mortality and immune efficiency were investigated in earthworms. G-Nut and GN-Free did not induce cytotoxic events in PBMCs, triggering the decrease in apoptotic (caspases 3 and 8) gene expression, lipid and protein oxidation levels, or pro-inflammatory cytokine levels. G-Nut and GN-Free did not trigger earthworm mortality and improved coelomocyte immune efficiency by increasing Eisenia neutrophil extracellular DNA traps and brown body formation when exposed to dead yeasts. The G-Nut nanoformulation is safe and can be used as a new form of food supplement by oral or transdermal delivery.
Assuntos
Bertholletia , Leucócitos Mononucleares , Nanopartículas , Oligoquetos , Paullinia , Extratos Vegetais , Ubiquinona , Animais , Oligoquetos/química , Humanos , Ubiquinona/análogos & derivados , Ubiquinona/farmacologia , Nanopartículas/química , Bertholletia/química , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Paullinia/química , Apoptose/efeitos dos fármacosRESUMO
Urban tropical lagoons are commonly impacted by silting, domestic sewage and industrial wastes and the dredging of their sediments is often required to minimize environmental impacts. However, the ecological implications of land disposal of dredged sediments are still poorly investigated in the tropics. Aiming to contribute to filling this gap, an ecotoxicological evaluation was conducted with dredged sediments from Tijuca Lagoon (Rio de Janeiro, Brazil) using different lines of evidence, including soil and sediment characterization, metal determination, and acute and avoidance bioassays with Eisenia andrei. Two different dredged sediment samples, a sandy sediment and another muddy one, were obtained in two distinct and spatially representative sectors of the Tijuca Lagoon. The sediments were mixed with an artificial soil, Ferralsol and Spodosol to obtain doses between 0 (pure soil) and 12%. The sediment dose that caused mortality (LC50) or avoidance responses (EC50) to 50% of the organisms was estimated through PriProbit analysis. Metal concentrations and toxicity levels were higher in the muddy sediment (artificial soil LC50 = 3.84%; Ferralsol LC50 = 4.58%; Spodosol LC50 = 2.85%) compared to the sandy one (artificial soil LC50 = 10.94%; Ferralsol LC50 = 14.36%; Spodosol LC50 = 10.38%), since fine grains tend to adsorb more organic matter and contaminants. Mortality and avoidance responses were the highest in Spodosol due to its extremely sandy texture (98% of sand). Metal concentrations in surviving earthworms were generally low, except sodium whose bioaccumulation was high. Finally, the toxicity is probably linked to marine salts, and the earthworms seem to accumulate water in excess to maintain osmotic equilibrium, increasing their biomass.
Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Oligoquetos , Sedimentos Geológicos/química , Animais , Brasil , Oligoquetos/efeitos dos fármacos , Solo/química , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análiseRESUMO
Co-exposure soil studies of pollutants are necessary for an appropriate ecological risk assessment. Here, we examined the effects of two-component mixtures of metal oxide nanoparticles (ZnO NPs or goethite NPs) with the insecticide chlorpyrifos (CPF) under laboratory conditions in short-term artificial soil assays using Eisenia andrei earthworms. We characterized NPs and their mixtures by scanning electron microscopy, atomic force microscopy, dynamic light scattering and zeta potential, and evaluated effects on metal accumulation, oxidative stress enzymes, and neurotoxicity related biomarkers in single and combined toxicity assays. Exposure to ZnO NPs increased Zn levels compared to control in single and combined exposure (ZnO NPs + CPF) at 72 h and 7 days, respectively. In contrast, there was no indication of Fe increase in organisms exposed to goethite NPs. One of the most notable effects on oxidative stress biomarkers was produced by single exposure to goethite NPs, showing that the worms were more sensitive to goethite NPs than to ZnO NPs. Acetylcholinesterase and carboxylesterase activities indicated that ZnO NPs alone were not neurotoxic to earthworms, but similar degrees of inhibition were observed after single CPF and ZnO NPs + CPF exposure. Differences between single and combined exposure were found for catalase and superoxide dismutase (goethite NPs) and for glutathione S-transferase (ZnO NPs) activities, mostly at 72 h. These findings suggest a necessity to evaluate mixtures of NPs with co-existing contaminants in soil, and that the nature of metal oxide NPs and exposure time are relevant factors to be considered when assessing combined toxicity, as it may have an impact on ecotoxicological risk assessment.
Assuntos
Clorpirifos , Nanopartículas Metálicas , Oligoquetos , Poluentes do Solo , Animais , Oligoquetos/efeitos dos fármacos , Clorpirifos/toxicidade , Nanopartículas Metálicas/toxicidade , Poluentes do Solo/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Óxido de Zinco/toxicidade , Inseticidas/toxicidade , Óxidos/toxicidadeRESUMO
Under laboratory conditions, the toxicological effects of pesticides tend to be less variable and realistic than under field conditions, limiting their usefulness in environmental risk assessment. In the current study, the earthworm Eisenia fetida was selected as a bioindicator for assessing glyphosate toxic effects in two different trials to solve this dilemma. In Trial 1, the worms were exposed for 7 and 14 days to concentrations of a commercial glyphosate formulation (1 to 500 mg a.i. kg-1) currently used in the field. In Trial 2, the worms were kept in nine soils collected from different plots with crops for 14 days of exposure. In both experiments, glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and acetylcholinesterase (AChE) activities and contents of lipid peroxidation (LPO) were evaluated. In T1, the glyphosate formulation produced a 40% inhibition of AChE activity and a significant increase in GST, SOD, CAT, and GPx activities and LPO contents in E. fetida on day 7. In T2, higher concentrations of glyphosate were detected in the soils of soybean, papaya, and corn (0.92, 0.87, and 0.85 mg kg-1), which induced a positive correlation between the levels of glyphosate residues with GST, SOD, CAT, GPx, and LPO and a negative correlation with AChE. These findings indicate that crop soils polluted with glyphosate elicited higher oxidative stress than under laboratory conditions, confirmed by IBRv2, PCA, and AHC analyses.
Assuntos
Glutationa Transferase , Glicina , Glifosato , Oligoquetos , Poluentes do Solo , Solo , Animais , Oligoquetos/efeitos dos fármacos , Glicina/análogos & derivados , Glicina/toxicidade , Poluentes do Solo/toxicidade , Solo/química , Glutationa Transferase/metabolismo , México , Catalase/metabolismo , Acetilcolinesterase/metabolismo , Glutationa Peroxidase/metabolismo , Superóxido Dismutase/metabolismo , Produtos Agrícolas , Herbicidas/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacosRESUMO
Mining is of great relevance to the global economy, but its activities are challenging due to socio-environmental impacts. In January 2019, an iron ore tailings dam collapsed in Brumadinho (Minas Gerais, Brazil) releasing 12 × 106 m3 of tailings, causing human losses and devastation around 3.13 × 106 m2 of a watershed. In this context, the present study aimed to investigate the potential toxic effects of tailings from the collapsed dam using earthworms Eisenia andrei as a model organism for terrestrial environments. An extensive set of tests was performed, including behavioral (avoidance), acute (mortality and biomass) and chronic tests, such as biomass, reproduction and cytotoxicity (viability and cell density and change in coelomocyte pattern). The physical-chemical characterization revealed a higher density of the tailings in relation to the control soil, which can result in physical changes, such as soil compaction and surface sealing. Aluminum, Ca, Fe, Hg, Mg, Mn, K, Na and P registered higher concentrations in the tailings compared to the control soil, while Total Nitrogen, Total Organic Carbon and Organic Matter were higher in the natural soil. Based on the avoidance test, an EC50 of 27.18 ± 2.83% was estimated. No lethality was observed in the acute exposure, nor variations in biomass in the acute and chronic assays. However, there was a tendency to reduce the number of juveniles in relation to cocoons in the proportions of 3125; 12.5 and 25%. Significant changes in viability, cell density and pattern of amebocytes and eleocytes were observed up to the 35th day of exposure. A multi-biomarker approach (Integrated Biological Response version 2) indicated concentration-dependent effects and attenuation of cellular changes over time. These are the first results of chronic effects on earthworms exposed to tailings from the B1 dam. Despite being conclusive, we highlight the possible heterogeneity of the tailings and the necessary care in extrapolating the results.
Assuntos
Desastres , Oligoquetos , Poluentes do Solo , Animais , Humanos , Solo/química , Mineração , Biomarcadores/metabolismo , Brasil , Poluentes do Solo/análiseRESUMO
Leachate, an effluent produced during solid waste decomposition, interacts directly with soil, mainly in dumpsite areas. Studies on terrestrial animal exposure to leachate are, however, lacking. Plants are the most frequently studied organisms, while animal studies, especially earthworms, are limited. Nevertheless, ecotoxicological assessments involving earthworms are crucial due to their role in soil health and ecosystem maintenance, which are paramount in understanding potential terrestrial ecosystem leachate effects. In this context, this study aimed to evaluate behavioral effects, sublethal cytotoxicity and antioxidant system alterations in Eisenia andrei earthworms chronically exposed to leachate from a closed dumpsite. Cytotoxicity was determined by coelomocyte density, viability and cell typing, while antioxidant system alterations were assessed through superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), reduced glutathione (GSH) and metallothionein (MT) determinations. Malondialdehyde (MDA) and protein carbonylation (PTC) levels were also determined as oxidative effect markers. Finally, the Biomarker Response Index (BRI) was assessed, aiming to quantitatively integrate the results of the investigated endpoints and establish a biological health state (BHS) for each leachate concentration. Leachate exposure led to leak responses at concentrations of up to 50%, but attraction at higher concentrations. Decreased cell density (28%) was observed after 48 days and reduced viability (50%), after 14 days of leachate exposure. The observed cell typing changes indicate anti-inflammatory immune system effects. Leachate exposure led to several antioxidant system alterations, increasing SOD (2-6 %), CAT (5-35 %) and GST (5-70 %) activities and GSH (7-37%) and MT (3-67%) levels. Earthworm antioxidant defenses were, however, able to prevent lipid peroxidation, which decreased (11-37%) following leachate exposure to concentrations above 12.5%, and PTC, which increased at 42 days (26%) and reduced at 56 days (12 %). This is the first PTC assessment in leachate-exposed earthworms. The increased carbonylation levels observed after 42 days alongside MDA decreases highlight the need for further research employing oxidative effect biomarkers other than MDA. Finally, an integrated approach employing the BRI was carried out, revealing mild initial changes evolving to moderate to major effects at the highest leachate exposure concentration, with an effect attenuation detected at the end of the experiment. In this sense, this study brings forth a significant novelty, employing a biomarker previously not assessed in earthworms, demonstrating an oxidative effect, alongside the use of the BRI as an integrative tool for the endpoints applied in this assessment.
Assuntos
Oligoquetos , Poluentes do Solo , Animais , Antioxidantes/metabolismo , Oligoquetos/metabolismo , Estresse Oxidativo , Ecossistema , Poluentes do Solo/toxicidade , Poluentes do Solo/metabolismo , Superóxido Dismutase/metabolismo , Solo , Biomarcadores/metabolismoRESUMO
The oligochaete Dero lutzi follows a life strategy that alternates between free-living periods in aquatic environments and endoparasitic phases. Most occurrences of D. lutzi in anurans are reported in species with arboreal habits, with studies limited to the recording of the oligochaete's presence in the host. Our study recovered specimens of D. lutzi from the tree frogs Scinax fuscovarius and Scinax. nasicus. We performed a morphological assessment of the parasite using light microscopy, for the first time, scanning electron microscopy. Molecular characterization of D. lutzi was carried out using the mitochondrial gene 16S rRNA and the nuclear gene 28S rRNA. Additionally, a phylogenetic tree was constructed to assess the species´position in relation to other group members. In our results, we confirmed the phenotypic morphological characteristics of the endoparasitic phase of D. lutzi. We also presented its phylogenetic position with other oligochaetes in the group, demonstrating the proximity between the endoparasite D. lutzi and the free-living oligochaete D. superterrenus.
Assuntos
Oligoquetos , Parasitos , Animais , Filogenia , RNA Ribossômico 16S , AnurosRESUMO
The widespread use of copper-based pesticides, while effective in controlling plant diseases, has been identified as a major source of copper contamination in soils. This raises concerns about potential adverse effects on earthworms, key players in soil health and ecosystem function. To inform sustainable pesticide practices, this study aimed to establish copper toxicity thresholds for earthworm avoidance in agricultural soils impacted by copper-based pesticides. We collected 40 topsoil samples (0-5 cm) from orchards and vineyards in the O'Higgins Region of central Chile, and 10 additional soils under native vegetation as background references. A standardized avoidance bioassay using Eisenia fetida assessed the impact of copper-based pesticides on the soils. Total copper concentrations ranged between 23 and 566 mg kg-1, with observed toxic effects on earthworms in certain soils. The effective concentration at 50% (EC50) for total soil copper, determined by Eisenia fetida's avoidance response, was 240 mg kg-1, with a 95% confidence interval of 193-341 mg kg-1. We further compared our EC50 values with existing data from agricultural soils impacted by mining activities. Interestingly, the results revealed a remarkable similarity between the thresholds for earthworm avoidance, regardless of the source of copper contamination. This observation underscores the universality of copper toxicity in agricultural ecosystems and its potential impact on soil biota. This study provides novel insights into copper toxicity thresholds for earthworms in real-world, pesticide-contaminated soils.
Assuntos
Oligoquetos , Praguicidas , Animais , Praguicidas/toxicidade , Cobre/toxicidade , Ecossistema , SoloRESUMO
Waste management practices are vital for human health and the environment in a world where natural resources stress is expected to increase with the growth of population. Our study aimed to evaluate the potential use of crop-livestock residue as a bulking agent associated with the ideal level of hydrated lime for the stabilization and sanitization of urban sewage sludge through the alkalization-composting process. Therefore, we determined the alkalization efficiency on the heavy metal concentration in urban sewage sludge, quantified the viable eggs of helminths in pure and alkalized sludge, and measured the rate of earthworms (Eisenia fetida) surviving in the vermicomposting process using different levels of alkalized urban sewage sludge associated with crop-livestock residue. Four sequential trials were carried out in a completely randomized design with three replicates. The lime alkalization reduced the levels of Ba, As, Pb, Cu, Cr, Mo, Ni, and Zn compared to the pure urban sewage sludge. Using 30% w/w of lime in the urban sewage sludge (SS-30) for composting process reduced the viable helminth eggs by 71, 72, and 69% for sugarcane bagasse (Saccharum officinarum; SB), fresh chopped Napier-grass (Pennisetum purpureum; NG), and bovine ruminal content (BR), respectively. The ideal level of hydrated lime for stabilization and sanitization of urban sewage sludge was found to be 30%, which was able to reduce the heavy metals. The residues have the potential as a bulking agent for the composting of urban sewage sludge when associated with alkalization. The lime alkalization decreases the total number of helminth eggs and the number of viable eggs. The possibility of starting a vermicomposting using the mixtures is promising, evidenced by the earthworm survival in composting urban sewage sludge mixed with crop-livestock residues after 45 days of composting. The earthworm survival is maintained by an association of at least 80% of the crop-livestock residues.
Assuntos
Cenchrus , Compostagem , Oligoquetos , Saccharum , Animais , Bovinos , Humanos , Celulose , Gado , EsgotosRESUMO
Soils that have a disproportion of metallic elements due to anthropic activities endanger the terrestrial fauna. This study evaluated whether earthworms (Eisenia foetida) exposed to ore tailings from Brumadinho region presented a higher frequency of genotoxic and mutagenic damages than annelids from a reference area (control). The animals were exposed to substrates containing 0%, 25%, 50%, 75%, and 100% iron mining waste. The results indicated increased DNA damage (p < 0.05), detected by the comet assay at 25% and 50%. There was a three-fold increase in micronuclei in animals on the substrates with the highest concentrations (75% and 100%) [F = 3.095; p = 0.02]. The earthworms lost weight as the percentage of mining waste increased. We concluded that E. foetida presented DNA damage in the contaminated soils of Brumadinho. However, more research is fundamental, once the environmental disaster in Brumadinho was one of the biggest mining catastrophe in Brazil.
Assuntos
Oligoquetos , Animais , Oligoquetos/genética , Mutagênicos/toxicidade , Brasil , Dano ao DNA , Ferro/toxicidade , Solo , Monitoramento Ambiental/métodosRESUMO
Chronic exposure to stress is a non-adaptive situation that is associated with mitochondrial dysfunction and the accumulation of reactive oxygen species (ROS), especially superoxide anion (SA). This accumulation of ROS produces damage-associated molecular patterns (DAMPs), which activate chronic inflammatory states and behavioral changes found in several mood disorders. In a previous study, we observed that an imbalance of SA triggered by rotenone (Ro) exposure caused evolutionarily conserved oxi-inflammatory disturbances and behavioral changes in Eisenia fetida earthworms. These results supported our hypothesis that SA imbalance triggered by Ro exposure could be attenuated by lithium carbonate (LC), which has anti-inflammatory properties. The initial protocol exposed earthworms to Ro (30 nM) and four different LC concentrations. LC at a concentration of 12.85 mg/L decreased SA and nitric oxide (NO) levels and was chosen to perform complementary assays: (1) neuromuscular damage evaluated by optical and scanning electron microscopy (SEM), (2) innate immune inefficiency by analysis of Eisenia spp. extracellular neutrophil traps (eNETs), and (3) behavioral changes. Gene expression was also evaluated involving mitochondrial (COII, ND1), inflammatory (EaTLR, AMP), and neuronal transmission (nAchR α5). LC attenuated the high melanized deposits in the circular musculature, fiber disarrangement, destruction of secretory glands, immune inefficiency, and impulsive behavior pattern triggered by Ro exposure. However, the effects of LC and Ro on gene expression were more heterogeneous. In summary, SA imbalance, potentially associated with mitochondrial dysfunction, appears to be an evolutionary component triggering oxidative, inflammatory, and behavioral changes observed in psychiatric disorders that are inhibited by LC exposure.
Assuntos
Oligoquetos , Estresse Oxidativo , Humanos , Animais , Espécies Reativas de Oxigênio/metabolismo , Oligoquetos/genética , Oligoquetos/metabolismo , Lítio/farmacologia , Rotenona/toxicidade , Superóxidos/metabolismo , Encéfalo/metabolismo , Superóxido Dismutase/metabolismo , Catalase/metabolismoRESUMO
Despite the importance of earthworms for soil formation, more is needed to know about how Pre-Columbian modifications to soils and the landscape. Gaining a deeper understanding is essential for comprehending the historical drivers of earthworm communities and the development of effective conservation strategies in the Amazon rainforest. Human disturbance can significantly impact earthworm diversity, especially in rainforest soils, and in the particular case of the Amazonian rainforest, both recent and ancient anthropic practices may be important. Amazonian Dark Earths (ADEs) are fertile soils found throughout the Amazon Basin, created by sedentary habits and intensification patterns of pre-Colombian societies primarily developed in the second part of the Holocene period. We have sampled earthworm communities in three Brazilian Amazonian (ADEs) and adjacent reference soils (REF) under old and young forests and monocultures. To better assess taxonomic richness, we used morphology and the barcode region of the COI gene to identify juveniles and cocoons and delimit Molecular Operational Taxonomic Units (MOTUs). Here we suggest using Integrated Operational Taxonomical units (IOTUs) which combine both morphological and molecular data and provide a more comprehensive assessment of diversity, while MOTUs only rely on molecular data. A total of 970 individuals were collected, resulting in 51 taxonomic units (IOTUs, MOTUs, and morphospecies combined). From this total, 24 taxonomic units were unique to REF soils, 17 to ADEs, and ten were shared between both soils. The highest richness was found in old forest sites for ADEs (12 taxonomic units) and REFs (21 taxonomic units). The beta-diversity calculations reveal a high species turnover between ADEs and REF soils, providing evidence that ADEs and REFs possess distinct soil biota. Furthermore, results suggest that ADE sites, formed by Pre-Columbian human activities, conserve a high number of native species in the landscape and maintain a high abundance, despite their long-term nature.