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1.
J Environ Manage ; 301: 113849, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34619586

RESUMO

Engine oil consists of hazardous substances that adversely affect the environment and soil quality. Bioremediation (employing organisms) is an appropriate technique to mitigate engine oil pollution. In the present study, the earthworm species, Drawida modesta (epigeic) and Lampito mauritii (anecic) were used to restore the soil polluted with polycyclic aromatic hydrocarbons (PAHs) and total petroleum hydrocarbons (TPHs) from used engine oil. Four treatments were set up in addition to positive and negative controls. A maximum of 68.6% PAHs and 34.3% TPHs removal in the treatment with soil (1 kg), cow dung (50 g), used engine oil (7.5 mL) and earthworms was recorded after 60 days. Undoubtedly, earthworms effectively removed PAHs and TPHs from the oil-contaminated soil. PAHs were more strongly accumulated in D. modesta (16.25 mg kg-1) than in L. mauritii (13.25 mg kg-1). Further, histological analysis revealed the epidermal surface irregularity, cellular disintegration, and cellular debris in earthworms. The pH (6.3%), electrical conductivity (12.7%), and total organic carbon (35.4%) were significantly (at P < 0.05) decreased after 60 days; while, total nitrogen (62%), total potassium (76.2%), and total phosphorus (19.2%) were substantially increased at the end of the experiment. The seed germination assay with fenugreek indicates that germination percentage (95%), and germination index (179), were dramatically increased in earthworm inoculated treatments when compared to the negative control (without earthworms). The results reveal that there is a great scope for utilizing the earthworms, D. modesta and L. mauritii for the bioremediation of soils contaminated with PAHs and TPHs.


Assuntos
Oligoquetos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Animais , Biodegradação Ambiental , Bovinos , Feminino , Hidrocarbonetos , Solo , Poluentes do Solo/análise
2.
Chemosphere ; 286(Pt 2): 131567, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34343920

RESUMO

Soil bacterial community (SBC) and fertility are pivotal for the evaluation of phytoremediation performance. Although affected by earthworms (E) and arbuscular mycorrhizal fungi (AMF), little is known about the impacts of the E-AMF interaction on the variation of SBC and fertility in cadmium (Cd)-spiked soil. We elucidated these impacts in rhizosphere soil of Solanum nigrum L. Loss of nutrient availability, and SBC diversity was observed in Cd-polluted soil. AMF increased available phosphorous (AP), whereas E increased available potassium (AK). In soils with 60 and 120 mg/kg Cd, the contents of AK, AP, and soil organic matter (SOM) increased by 7.0-19.7%, 23.7-25.5%, and 11.5-17.4%, respectively; and the residual Cd after remediation decreased by 7.9-8.5% in soils treated with EAM compared to untreated soil. EAM-treated soil had higher alpha diversity estimators compared to uninoculated soil. The predominant bacterial phyla were Proteobacteria and Bacteroidetes, accounting for 72.5-84.0%. Redundancy analysis showed that total carbon (TC), SOM, pH, and C/N ratio were key factors determining SBC at the phylum level, explaining 26.9, 24.1, 15.1, and 14.8% of the total variance, respectively. These results suggested that EAM affected SBC composition by altering SOM, TC, and C/N ratio. The E-AMF cooperation ameliorates soil nutrients, SBC diversity, and composition, facilitating phytoextraction processes.


Assuntos
Microbiota , Micorrizas , Oligoquetos , Poluentes do Solo , Animais , Cádmio/análise , Fertilidade , Fungos , Raízes de Plantas/química , Solo , Microbiologia do Solo , Poluentes do Solo/análise
3.
Chemosphere ; 286(Pt 2): 131707, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34365170

RESUMO

2-Pentanone is an excellent organic solvent and extractant, which is widely used in industrial production. 2-Pentanone is harmful to soil organisms when it enters the soil. However, current studies have not clarified the response of the antioxidant enzyme superoxide dismutase (SOD) to 2-Pentanone and its mechanism. In this study, the response of earthworm antioxidant enzyme SOD to 2-Pentanone and its molecular mechanism was investigated at organism molecular levels. The results showed that the SOD activity of earthworms under 2-Pentanone stress was significantly inhibited, and the inability of superoxide anion radicals (·O2-) to be scavenged in time might be one of the reasons for the increase of lipid peroxidation. Under 2-Pentanone exposure conditions, catalase (CAT), an antioxidant enzyme closely related to SOD, and the total antioxidant capacity (T-AOC) of earthworms were activated to resist oxidative damage. On the other hand, the observation of earthworm microstructure provided evidence of a direct risk of 2-Pentanone on earthworm body wall tissues. Molecular-level assays have shown that 2-pentanone altered the secondary structure of SOD, which further led to the loosening of the SOD backbone structure and the extension of the polypeptide chain. On the other hand, 2-pentanone quenched the endogenous fluorescence of SOD in the form of static quenching and formed the 2-pentanone/SOD complex. Molecular simulation results suggested that 2-pentanone tended to bind on the surface of SOD rather than close to the active site, and it is speculated that the alteration of SOD structure is the key reason for the change in its activity. This study enriches the toxicological data of 2-Pentanone on soil organisms, thus responding to the current concerns about its ecological risk.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Catalase/metabolismo , Malondialdeído , Oligoquetos/metabolismo , Estresse Oxidativo , Pentanonas , Poluentes do Solo/toxicidade , Superóxido Dismutase/metabolismo
4.
Chemosphere ; 286(Pt 3): 131945, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34426272

RESUMO

Vermicomposting of food waste amended with biochar and cow dung was studied during a 90-day composting period. The improvement of the vermicomposting process by adding three mangrove fungal species as additional amendments were studied. The use of mangrove fungi Acrophialophora jodhpurensis as a bio-catalytic actor during vermicomposting proved to be beneficial in terms of final compost quality (available N, P and K) and the shortening of the composting period. All three fungal species, however, reached the neutral pH at the end of the composting period and appeared to be beneficial. Heavy metal (Cd, Ni, Pb, Zn, Cu and Cr) concentrations decreased throughout the composting process. Food waste can be treated using vermicomposting with biochar, cow dung and the mangrove fungi A. jodhpurensis. The final vermicomposting product is suitable for agricultural use.


Assuntos
Oligoquetos , Eliminação de Resíduos , Animais , Carvão Vegetal , Alimentos , Alimentos Orgânicos , Fungos , Sordariales
5.
Sci Total Environ ; 802: 149792, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34464790

RESUMO

The eco-sustainability of industrial processes relies on the proper exploitation of by-products and wastes. Recently, brewers' spent grain (BSG), the main by-product of brewing, was successfully recycled through vermicomposting to produce an organic soil conditioner. However, the pre-processing step there applied (oven-drying) resulted in high costs and the suppression of microbial species beneficial for soil fertility. To overcome these limitations, a low-input pre-processing step was here applied to better exploit BSG microbiota and to make BSG suitable for vermicomposting. During 51 days of pre-treatment, the bacterial and fungal communities of BSG were monitored by denaturing gradient gel electrophoresis (DGGE). Chemical (carbon, nitrogen, ammonium, nitrate content, dissolved organic carbon) and biochemical (dehydrogenase activity) parameters were also evaluated. Mature vermicompost obtained from pre-processed BSG was characterized considering its legal requirements (e.g., absence of pathogens and mycotoxins, lack of phytotoxicity on seeds), microbiota composition, and chemical properties. Results obtained showed that throughout the pre-process, the BSG microbiota was enriched in bacterial and fungal species of significant biotechnological and agronomic potential, including lactic acid bacteria (Weissella, Pediococcus), plant growth-promoting bacteria (Bacillus, Pseudomonas, Pseudoxhantomonas), and biostimulant yeasts (Pichia fermentans, Trichoderma reesei, Beauveria bassiana). Pre-processing increased the suitability of BSG for earthworms' activity to produce high-quality mature vermicompost.


Assuntos
Lactobacillales , Oligoquetos , Animais , Grão Comestível , Hypocreales , Pichia
6.
Sci Total Environ ; 804: 149994, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34798714

RESUMO

Most ecosystem functions attributed to earthworms are mediated by their internal microbiomes, and these are sensitive to disturbances in the external environment. However, few studies have focused on the response of the earthworm gut microbiome to soil chronosequence. Here, we used 16S rRNA high-throughput sequencing and high-throughput quantitative PCR to investigate the variations in bacterial communities and functional gene abundance in earthworm (Lumbricina sp.) guts and upland soils under 700 years of cultivation. Our results indicated that 700 years of upland cultivation significantly shaped bacterial communities and increased functional traits of microbes in earthworm guts, which were more sensitive to cultivation age compared to the surrounding soils. The earthworm gut bacterial community changed rapidly over the first 300 years of cultivation and then changed slowly in the following centuries. Along with the cultivation age, we also observed that the earthworm gut microbiota was successive towards a copiotrophic strategy (e.g., Xanthobacteraceae, Nocardioidaceae, Hyphomicrobiaceae, and Bacillaceae) and higher potential functions (e.g., ureC, nirS, nosZ, phoD, and pqqC). Furthermore, canonical correspondence analysis further revealed that soil pH, C:N ratio, soil organic carbon, and total nitrogen were key abiotic drivers shaping earthworm gut bacterial communities. Taken together, this study reveals the succession of bacterial communities and potential functions in earthworm guts within 700 years of upland cultivation, which may provide a broader space for us to rationally exploit and utilize the interactions between soil and earthworm gut microbiotas to benefit the soil nutrient cycling process.


Assuntos
Microbioma Gastrointestinal , Microbiota , Oligoquetos , Animais , Carbono , RNA Ribossômico 16S/genética , Solo , Microbiologia do Solo
7.
Environ Pollut ; 291: 118215, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34740293

RESUMO

Laboratory experiments in which earthworms were exposed to four different Sb spiked agricultural soils (acidic, neutral, alkaline and calcareous alkaline soil) were conducted in a climate-controlled room. The study surveyed the toxicity of Sb to the Eisenia fetida at the individual (mortality, growth inhibition, Sb accumulation), physiological (enzymatic activities), subcellular and tissue levels (histological damage), and for the induction of an avoidance response of Sb. The results showed that earthworms clearly avoided Sb spiked soil, and the avoidance response tended to be correlated to the exposure dose. The EC50 values of the net avoidance response in the four soils were as followed: S1 (acidic soil, 135 ± 37 mg kg-1) < S3 (alkaline soil, 430 ± 114 mg kg-1) < S4 (calcareous alkaline soil, 455 ± 29 mg kg-1) < S2 (neutral soil, 946 ± 151 mg kg-1). Different toxic effects of Sb to earthworms cultivated in the four types of soils were observed. Antimony was more toxic in a sandy alkaline soil than that in the other three soils tested. The LC50 of the 28 d mortality ranged as follows: S3 (22.2 ± 0.1 mg kg-1) < S2 (372 ± 177 mg kg-1) < S4 (491 ± 140 mg kg-1) < S1 (497 ± 29 mg kg-1). Changes in oxidative stress and the subcellular distribution of Sb in earthworms induced by Sb exposure differed between soil types. Additionally, histological damage in earthworm's epidermis and intestine were observed under Sb stress. Mortality, growth inhibition and Sb accumulation in the earthworms tended to increase with Sb exposure regardless of soil type and were all significantly correlated with the exposure dose. The growth inhibition and Sb concentration in tissues of earthworms were sensitive indicators of Sb bioavailability. The relatively comprehensive toxicological data provided herein can contribute to the toxicity threshold and assessment of bioavailability of Sb contaminated agricultural soil, and then to the ecological risk assessments.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Antimônio/toxicidade , Disponibilidade Biológica , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
8.
Artigo em Inglês | MEDLINE | ID: mdl-34769748

RESUMO

Pesticide adjuvants (PAs) are important components of pesticide. Nonetheless, limited information is available regarding their toxic effects on biota in terrestrial ecosystem. In the present study, the mortality, growth inhibition ratio, and avoidance behavior of Eisenia fetida were examined to investigate the ecotoxicological effects of toluene, xylene, and trichloroethylene and further their mixture. The 24 h median lethal concentration (24 h-LC50) of the three PAs were 300.23, 1190.45, and 5332.36 mg/kg, and the 48 h-LC50 values were 221.62, 962.89, and 4522.41 mg/kg, respectively. The mixture exhibited significant synergistic effect on the E. fetida. There was significant growth inhibition on E. fetida by the tested PAs. The avoidance threshold values of E. fetida for the tested PAs were 1100 mg/kg, 250 mg/kg, 5000 mg/kg, and 25% of the mixture, respectively. The results evaluated the toxic effects of the three PAs and their mixture on E. fetida, provided a basis for ecotoxicological risk assessment of PAs in the soil ecosystem.


Assuntos
Oligoquetos , Praguicidas , Poluentes do Solo , Animais , Ecossistema , Praguicidas/toxicidade , Medição de Risco , Poluentes do Solo/análise
9.
Ecotoxicol Environ Saf ; 227: 112949, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34755633

RESUMO

The current environmental hazard assessment is based on the testing of the pristine substance. However, it cannot be excluded that (nano)pharmaceuticals are excreted into sewage during the use phase followed by entry into wastewater treatment plants (WWTPs). Sorption to sewage sludge or release via effluent can result in modified ecotoxicological effects which possibly can only be detected with a modified test approach. The objective of our study was to investigate a realistic exposure scenario for metallic nanoparticles (NPs) in pharmaceutical products, excreted into effluent, and released into the environment after treatment in WWTPs. The test approach was illustrated by using gold (Au) NPs. Effluent from model WWTPs were investigated in aquatic tests (Daphnia magna, fish cell lines). Sewage sludge was used as a sole food source (Eisenia fetida) or mixed with soil and used as test medium (soil microorganisms, Folsomia candida, Enchytraeus crypticus). To cover the aspect of regulation, the test systems described in OECD-test guidelines (OECD TG 201, 211, 220, 232, 249, 317) were applied. Modifications and additional test approaches were included to meet the needs arising out of the testing of nanomaterials and of the exposure scenarios. The results were assessed regarding the suitability of the test design and the toxicity of Au-NPs. Except for activated sludge as a sole food source for E.fetida, the selected test approach is suitable for the testing of nanomaterials. Additional information can be gained when compared to the common testing of the pristine nanomaterials in the standardized test systems. Effects of Au-NPs were observed in concentrations exceeding the modeled environmental.


Assuntos
Nanopartículas Metálicas , Oligoquetos , Preparações Farmacêuticas/análise , Animais , Linhagem Celular , Daphnia , Ecotoxicologia , Peixes , Nanopartículas Metálicas/análise , Nanopartículas Metálicas/toxicidade , Esgotos , Testes de Toxicidade
10.
Artigo em Inglês | MEDLINE | ID: mdl-34639598

RESUMO

The distribution of organisms is governed by their habitat condition. We analyzed bacterial communities in the gut of the blackworm Lumbriculus variegatus by pyrosequencing of the extracted intestinal metagenomic DNA. Blackworms were collected from two sampling sites with differences in irradiance and riparian vegetation, where site GP7 was covered by riparian vegetation and site GP8 was exposed to sunlight. We obtained the filtered 6414 reads from three samples of each site. At GP7, 271 OTUs were identified, including 32 OTUs unique to the site, whereas at GP8, 238 OTUs were identified, including 22 unique OTUs. Among them, 18 OTUs were shared between both sites. The phylum Proteobacteria was a major component contributing 67.84% and 64.05% of sequences at sites GP7 and GP8, respectively, while each remaining phylum contributed less than 10% at both sites. The two sites differed in microbial community composition and KEGG-indicated biochemical pathways. Community indices such as species richness and Shannon diversity were higher at site GP7 than at GP8. Meanwhile, the abundance of Cyanobacteria was significantly higher at site GP8, while site GP7 showed a greater proportion of genes for membrane transport and carbohydrate metabolism, reflecting differences in food resources.


Assuntos
Cianobactérias , Microbioma Gastrointestinal , Oligoquetos , Animais , Água Doce , Microbioma Gastrointestinal/genética , Proteobactérias/genética , RNA Ribossômico 16S
11.
Ecotoxicol Environ Saf ; 226: 112861, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34628156

RESUMO

Natural ecosystems are frequently exposed to complex mixtures of different chemicals. However, the environmental risk assessment is mainly based on data from individual substances. In this study, the individual and combined effects on the terrestrial earthworm E. fetida exposed to the anionic surfactant sodium lauryl ether sulphate (SLES) and the pesticides chlorpyrifos (CPF) and imidacloprid (IMI) were investigated, by using the avoidance behaviour as endpoint. Earthworms were exposed to a soil artificially contaminated with five sub-lethal concentrations of each contaminant, both as single substances and in combination of binary and ternary mixtures. Overall results showed that IMI provoked the highest avoidance effect on earthworms, with a concentration value that induced an avoidance rate of 50% of treated organisms (AC50) of 1.30 mg/kg, followed by CPF (AC50 75.26 mg/kg) and SLES (AC50 139.67 mg/kg). The application of the Combination Index (CI) method, indicated that a deviation from the additive response occurred for most of the tested chemical mixtures, leading to synergistic or antagonistic avoidance responses. Synergistic effects were produced by the exposure to the two lowest concentrations of the CPF+IMI mixture, and by the highest concentrations of SLES+CPF and SLES+CPF+IMI mixtures. On the contrary, antagonistic effects were observed at the lowest concentrations of the binary mixtures containing the SLES and at almost all the tested concentrations of the SLES+CPF+IMI mixture (with the exception of the highest tested concentration). These results show that the avoidance test is suitable to assess the detrimental effects exerted on earthworms by chemical mixtures in soil ecosystems and the use of behavioural endpoints can increase the ecological significance of environmental risk assessment procedures.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Aprendizagem da Esquiva , Ecossistema , Solo , Poluentes do Solo/toxicidade
12.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3327-3334, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34658219

RESUMO

In this study, we examined the toxic effect of sublethal doses of acetochlor (1, 2, 4, 8 mg·kg-1) on earthworms by exogenous addition. The growth inhibition rate, cytochrome P450 isozymes (CYP1A2, 2C9 and 3A4) activities and the metabolomics were analyzed after seven days of exposure, to infer the toxicity threshold of acetochlor, screen the sensitive biomarkers from the levels of the individual, detoxified enzymes and small molecular metabolites, and elucidate the underlying toxicity mechanism. The results showed that CYP1A2, 2C9 and 3A4 activities were all significantly inhibited, and that the levels of ten metabolites (fructose-6-diphosphate, cytosine monophosphate, uridine monophosphate, adenosine monophosphate, adenosine, xanthine, fumaric acid, dihydroxyglutaric acid, ornithine and 16-hydroxyeicosatetraenoic acid) were significantly decreased by acetochlor exposure. The levels of six metabolites (adenosine succinic acid, succinic acid, arginine, tryptophan, asparagine and phenylalanine) were significantly increased when earthworms being exposed to 2-8 mg·kg-1 acetochlor. Acetochlor exposure caused oxidative damage to earthworms, weakened the glycolysis, disturbed the tricarboxylic acid cycle, disordered the purine and pyrimidine metabolism, and impaired the amino acids metabolism. Compared with the end point at individual level, the above 16 small molecule metabolites and CYP isozymes activities were more sensitive to acetochlor exposure. It was thus recommended that CYP isozymes (1A2, 2C9, and 3A4) activities and small molecular metabolites could be used as a set of biomarkers to diagnose the acetochlor pollution, given their high sensitivity and accuracy.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Toluidinas/análise , Toluidinas/toxicidade
13.
Folia Parasitol (Praha) ; 682021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34642289

RESUMO

Stomatocystis goerresi sp. n., a gregarine (phylum Apicomplexa, Monocystidae) parasite of an important invasive earthworm in North America, Amynthas tokioensis (Beddard), is described. This is the second species placed into the genus, and details of its morphology and life cycle support Stomatocystis Bandyopadhyay, Mitra et Göçmen, 2006 as a valid taxon. The new species is described using standard nomenclature, measurements, shape descriptors, and photographs of living cells. The parasite was found only in A. tokioensis, and absent in sympatric earthworm species, suggesting it arrived when the earthworms were introduced from their origin from Japan. The species is distinctive from the type species in the genus, S. indica Bandyopadhyay, Mitra et Göçmen, 2006, in being substantially larger in all stages, found in only the host's seminal vesicles, and found in a different host species from East Asia. The distinctive trophozoites/gamonts develop a large funnel structure ringed with a collar of pronounced ridges, and the funnel appears even in the smallest cells. This funnel varies greatly in relative size (to the cell body) and shape, sometimes forming a large fan. The life cycle of S. goerresi is described including distinctive syzygy in which the funnels fuse and then produce a large cell with local centres of isogamete production (thus sex without gender). Gametes are large ( ~5 µm) spheres with complex tips. Oocyst production is large, > 1,000 per mature gametocyst. The genus Stomatocystis is placed into the Monocystidae, but the life cycle of the new species differs from those of other monocystid taxa, which may mean the Monocystidae are not monophyletic or life cycles are variable within the family. Prevalence of S. goerresi at the type locality was high (~ 90%). The parasites destroy the earthworm's organ of sperm self-storage thus eliminating the male function in the hermaphroditic host which may influence the ability of the earthworm to invade and be successful at new sites.


Assuntos
Apicomplexa/crescimento & desenvolvimento , Apicomplexa/isolamento & purificação , Animais , Apicomplexa/classificação , Apicomplexa/genética , Espécies Introduzidas , Japão , Estágios do Ciclo de Vida , Masculino , Oligoquetos/parasitologia
14.
J Environ Sci (China) ; 109: 171-180, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34607666

RESUMO

Polymyxin B (PMB) is considered as the last line of antibiotic defense available to humans. The environmental effects of the combined pollution with PMB and heavy metals and their interaction mechanisms are unclear. We explored the effects of the combined pollution with PMB and arsenic (As) on the microbial composition of the soil and in the earthworm gut, as well as the spread and transmission of antibiotic resistance genes (ARGs). The results showed that, compared with As alone, the combined addition of PMB and As could significantly increase the bioaccumulation factor and toxicity of As in earthworm tissues by 12.1% and 16.0%, respectively. PMB treatment could significantly increase the abundance of Actinobacteria in the earthworm gut (from 35.6% to 45.2%), and As stress could significantly increase the abundance of Proteobacteria (from 19.8% to 56.9%). PMB and As stress both could significantly increase the abundance of ARGs and mobile genetic elements (MGEs), which were positively correlated, indicating that ARGs might be horizontally transferred. The inactivation of antibiotics was the main resistance mechanism that microbes use to resist PMB and As stress. Network analysis showed that PMB and As might have antagonistic effects through competition with multi-drug resistant ARGs. The combined pollution by PMB and As significantly promoted the relative abundance of microbes carrying multi-drug resistant ARGs and MGEs, thereby increasing the risk of transmission of ARGs. This research advances the understanding of the interaction mechanism between antibiotics and heavy metals and provides new theoretical guidance for the environmental risk assessment and combined pollution management.


Assuntos
Arsênio , Microbioma Gastrointestinal , Oligoquetos , Animais , Antibacterianos/toxicidade , Arsênio/toxicidade , Genes Bacterianos , Polimixina B/toxicidade , Solo
15.
Ecotoxicol Environ Saf ; 227: 112891, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34649139

RESUMO

Vermicomposting of Biomedical waste ash (BA) by the earthworm Eisenia fetida was studied with cow dung (CD) as nutrient medium. For 105 days, experiment was carried out in seven vermireactors containing varying ratios of BA and CD. Earthworm activity significantly reduced the pH (8.61-7.24), Electrical conductivity (EC) (4.1-1.62), Total organic carbon (TOC) (38.6-14.92), and Carbon and nitrogen (C/N ratios) (145.4-8.2) of all BA ratios. Levels of Total kjeldahl nitrogen (TKN) (0.26-1.82), Total available phosphorus (TAP) (0.22-0.64), Total potassium (TK) (2.05-12.08), and Total sodium (TNa) (47.53-92.26) were found to be increasing in the postvermicompost mixture. Although heavy metals content decreased from initial to final, it becomes below the permissible limits in the end product. The results showed that earthworm growth and fecundity were best in vermireactors containing 10-25% of BA. The best reproduction and growth of earthworms, demonstrate the vermicomposting's ability to manage hazardous solid wastes like BA. Use of vermitechnology to manage BA has not been performed yet in any kind of the research. Finally, it was determined that vermicomposting can be incorporated into overall plan for BA management. Thus nutrient-rich, detoxified, and physiochemically stable product may be used safely in agricultural processes.


Assuntos
Metais Pesados , Oligoquetos , Animais , Bovinos , Ecossistema , Feminino , Esterco , Nutrientes , Solo
16.
Aquat Toxicol ; 239: 105955, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34500378

RESUMO

Oligochaetes feed on bulk sediment and penetrate the sediment through the construction of burrows, making them especially vulnerable to sediment metal contamination. However, the few oligochaete species that have been tested to date are almost exclusively temperate test species. Although the warmwater adapted species Branchiura sowerbyi has been indicated as a promising candidate for tropical sediment toxicity testing, few (especially chronic) studies have been conducted so far to confirm this. Therefore, the aim of the present study was to evaluate the bioaccumulation and chronic 28d lethal and sublethal toxicity of arsenic (As) and zinc (Zn) to both the warmwater-adapted B. sowerbyi and the coldwater-adapted oligochaete Tubifex tubifex for comparison. Arsenic was more toxic to both oligochaete species than Zn. Inter- and intra-species variability in toxicity values of the two test species and other benthic invertebrates was within an order of magnitude. However, B. sowerbyi was the most sensitive species to As even for sediment concentration (EC50: 36.6 ± 2.1 µg/g and 147.1 ± 21.7 µg/g, for B. sowerbyi and T. tubifex, respectively) and for tissue concentration (ER50: 9.2 ± 0.9 µg/g and 887.0 ± 35.0 µg/g, for B. sowerbyi and T. tubifex, respectively). Finally, the Tissue Residue-effects Approach (TRA) using Effective Tissue Residues appears to be a promising way forward in advancing in this since it considers internal body concentrations.


Assuntos
Arsênio , Oligoquetos , Poluentes Químicos da Água , Animais , Arsênio/toxicidade , Bioacumulação , Sedimentos Geológicos , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade
17.
Environ Pollut ; 290: 118041, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523513

RESUMO

The presence of manufactured nano-objects (MNOs) in various consumer or their (future large-scale) use as nanoagrochemical have increased with the rapid development of nanotechnology and therefore, concerns associated with its possible ecotoxicological effects are also arising. MNOs are releasing along the product life cycle, consequently accumulating in soils and other environmental matrices, and potentially leading to adverse effects on soil biota and their associated processes. Earthworms, of the group of Oligochaetes, are an ecologically significant group of organisms and play an important role in soil remediation, as well as acting as a potential vector for trophic transfer of MNOs through the food chain. This review presents a comprehensive and critical overview of toxic effects of MNOs on earthworms in soil system. We reviewed pathways of MNOs in agriculture soil environment with its expected production, release, and bioaccumulation. Furthermore, we thoroughly examined scientific literature from last ten years and critically evaluated the potential ecotoxicity of 16 different metal oxide or carbon-based MNO types. Various adverse effects on the different earthworm life stages have been reported, including reduction in growth rate, changes in biochemical and molecular markers, reproduction and survival rate. Importantly, this literature review reveals the scarcity of long-term toxicological data needed to actually characterize MNOs risks, as well as an understanding of mechanisms causing toxicity to earthworm species. This review sheds light on this knowledge gap as investigating bio-nano interplay in soil environment improves our major understanding for safer applications of MNOs in the agriculture environment.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Bioacumulação , Ecotoxicologia , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
18.
Environ Pollut ; 290: 118038, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523524

RESUMO

Isoprocarb (IPC) is a conventional carbamate with high insecticidal activity, however, generalized use of it may cause soil contamination and adversely implicate non-target biota. Following OECD standardized toxicological protocols, the toxic effects of IPC on Eisenia fetida at lethal and sublethal concentrations were examined to elucidate its toxic modes of action as well as biochemical and detoxification responses of E. fetida. Acute toxicity tests showed that IPC induced a concentration-dependent rise of mortality, with LC50 of 8.20 µg/cm2 (48 h) in FPCT and 3.37 mg/kg (14 d) in AST, respectively. The ecotoxicological effects of IPC chronic exposure were measured by physiochemical, qRT-PCR and western blot analysis. Specifically, ROS, MDA and 8-OHdG contents were enhanced and T-AOC, SOD, CAT and POD activities diminished with increasing concentrations. While activities of CYP3A4 and CarE as well as expressions of Hsp70, GPx and GST were elevated upon IPC treatments, responsible for detoxifying mechanisms as implied by principal component analysis (PCA). Meanwhile, IPC diminished NRRT and inhibited AChE activities along with expressions of AChE-related genes. All these striking alterations between IPC-exposed earthworms and controls were illustrated in PCA model. More importantly, growth, reproductive and regenerative toxicity of IPC were observed with reduced cast production and soluble protein content, suppressed ANN protein and gene expressions, reversely modulated TCTP and Sox2 gene and protein, respectively. Taken together, deleterious perturbations could be induced by IPC in biophysiological homeostasis of E. fetida primarily through oxidative stress and neural dysfunction. This study not only highlighted potential hazard of IPC to earthworms in the terrestrial ecosystem, but also expounded upon mechanisms underlying toxic modes of action for IPC and detoxification of earthworms.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Carbamatos , Ecossistema , Estresse Oxidativo , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
19.
Lab Anim (NY) ; 50(10): 285-294, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34489599

RESUMO

Enchytraeids (Annelida) are soil invertebrates with worldwide distribution that have served as ecotoxicology models for over 20 years. We present the first high-quality reference genome of Enchytraeus crypticus, assembled from a combination of Pacific Bioscience single-molecule real-time and Illumina sequencing platforms as a 525.2 Mbp genome (910 gapless scaffolds and 18,452 genes). We highlight isopenicillin, acquired by horizontal gene transfer and conferring antibiotic function. Significant gene family expansions associated with regeneration (long interspersed nuclear elements), the innate immune system (tripartite motif-containing protein) and response to stress (cytochrome P450) were identified. The ACE (Angiotensin-converting enzyme) - a homolog of ACE2, which is involved in the coronavirus SARS-CoV-2 cell entry - is also present in E. crypticus. There is an obvious potential of using E. crypticus as a model to study interactions between regeneration, the innate immune system and aging-dependent decline.


Assuntos
COVID-19 , Oligoquetos , Animais , Humanos , Sistema Imunitário , Oligoquetos/genética , SARS-CoV-2 , Solo
20.
Nanoscale ; 13(35): 14666-14678, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533558

RESUMO

Assessing the risks of nanomaterials/nanoparticles (NMs/NPs) under various environmental conditions requires a more systematic approach, including the comparison of effects across many NMs with identified different but related characters/descriptors. Hence, there is an urgent need to provide coherent (eco)toxicological datasets containing comprehensive toxicity information relating to a diverse spectra of NPs characters. These datasets are test benches for developing holistic methodologies with broader applicability. In the present study we assessed the effects of a custom design Fe-doped TiO2 NPs library, using the soil invertebrate Enchytraeus crypticus (Oligochaeta), via a 5-day pulse via aqueous exposure followed by a 21-days recovery period in soil (survival, reproduction assessment). Obviously, when testing TiO2, realistic conditions should include UV exposure. The 11 Fe-TiO2 library contains NPs of size range between 5-27 nm with varying %Fe (enabling the photoactivation of TiO2 at energy wavelengths in the visible-light range). The NPs were each described by 122 descriptors, being a mixture of measured and atomistic model descriptors. The data were explored using single and univariate statistical methods, combined with machine learning and multiscale modelling techniques. An iterative pruning process was adopted for identifying automatically the most significant descriptors. TiO2 NPs toxicity decreased when combined with UV. Notably, the short-term water exposure induced lasting biological responses even after longer-term recovery in clean exposure. The correspondence with Fe-content correlated with the band-gap hence the reduction of UV oxidative stress. The inclusion of both measured and modelled materials data benefitted the explanation of the results, when combined with machine learning.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Oligoquetos , Animais , Aprendizado de Máquina , Nanopartículas/toxicidade , Titânio/toxicidade
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