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1.
Environ Pollut ; 320: 121020, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36632970

RESUMO

Metabolomic and gut microbial responses of soil fauna to environmentally relevant concentrations of microplastics indicate the potential molecular toxicity of microplastics; however, limited data exist on these responses. In this study, earthworms (Eisenia fetida) were exposed to spherical (25-30 µm diameter) polystyrene microplastic-contaminated soil (0.02%, w:w) for 14 days. Changes in weight, survival rate, intestinal microbiota and metabolic responses of the earthworms were assessed. The results showed that polystyrene microplastics did not influence the weight, survival rate, or biodiversity of the gut microbiota, but significantly decreased the relative abundance of Bacteroidetes at the phylum level. Moreover, polystyrene microplastics disturbed the osmoregulatory metabolism of earthworms, as indicated by the significantly decreased betaine, myo-inositol and lactate, and increased 2-hexyl-5-ethyl-furan-3-sulfonic acid at the metabolic level. This study provides important insights into the molecular toxicity of environmentally relevant concentrations of polystyrene microplastics on soil fauna.

2.
J Hazard Mater ; 427: 128176, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-34996001

RESUMO

Examining transcriptomic and metabolic responses of earthworms to microplastic-contaminated soil is critical for understanding molecular-level toxicity of microplastics; yet very little research on this topic exists. We investigated influences of environmentally relevant concentrations (ERC) of polypropylene (PP) and polyethylene (PE) microplastic-contaminated soil on earthworms at the transcriptomic, metabolic, tissue and whole-body levels to study their molecular toxicity. The addition of PP and PE at ERC induced oxidative stress on earthworms, as indicated by the high enrichment of glutathione metabolism and increased glutamine at the transcriptomic and metabolic levels. Digestive and immune systems of earthworms were damaged according to the injuries of the intestinal epithelium, partial shedding of chloragogenous tissues and unclear structure of coelom tissues, which were confirmed by pathway analysis at the transcriptomic level. Significant enrichment of arachidonic acid and glycerolipid metabolisms indicated that PP and PE disturbed the lipid metabolism in earthworms. Significantly increased betaine and myo-inositol, and decreased 2-hexyl-5-ethyl-3-furansulfonate suggested that PP and PE caused differences in osmoregulation extent. In conclusion, most similar responses of earthworm might result from special size rather than type effects of PP and PE microplastics. Contamination of soils with microplastics even at ERC has health risks to earthworms; therefore, proper management of microplastics to reduce their input to the environment is key to reducing the health risks to soil fauna.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Microplásticos , Oligoquetos/genética , Plásticos/toxicidade , Polietileno/toxicidade , Polipropilenos/toxicidade , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Transcriptoma
3.
J Hazard Mater ; 398: 122825, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32768809

RESUMO

The toxicity of low-level arsenic (As)-contaminated soil is not well understood. An integrated proteomic and metabolomic approach combined with morphological examination was used to investigate the potential biological toxicity of As-contaminated soil based on an exposure experiment with the earthworm Eisenia fetida. The results showed that the earthworm hindgut accumulated high As concentrations resulting in injury to the intestinal epithelia, chloragogenous tissues and coelom tissues. Furthermore, As-contaminated soil induced a significant increase in betaine levels and a decrease in dimethylglycine and myo-inositol levels in the earthworms, suggesting that the osmoregulatory metabolism of the earthworms may have been disturbed. The significantly altered levels of asparagine and dimethylglycine were proposed as potential biomarkers of As-contaminated soil. The upregulation of soluble calcium-binding proteins and profilin, the downregulation of sodium/potassium-transporting ATPase, and the proteins changes identified by gene ontology enrichment analysis confirmed that the earthworms suffered from osmotic stress. In addition, the significant changes in glycine-tRNA ligase activity and coelomic tissue injury revealed that As accumulation may disturb the earthworm immune system. This work provided new insight into the proteomic and metabolic toxicity of low-level As-contaminated soil ecosystems in earthworms, extended our knowledge of dual omics and highlighted the mechanisms underlying toxicity.


Assuntos
Arsênio , Oligoquetos , Poluentes do Solo , Animais , Arsênio/análise , Arsênio/toxicidade , Ecossistema , Metabolômica , Proteômica , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
4.
Ecotoxicol Environ Saf ; 189: 109948, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31759738

RESUMO

Proper protocols for assessing the remediation effectiveness of contaminated soils are an important part of remediation projects. In the present study, the residual immobilization effectiveness of hydrated lime (L), hydroxyapatite (H), biochar (B) and organic fertilizer (F) alone and in combination was assessed by Eisenia fetida. The results showed that the application of amendments had no significant effect on the death rate and average fresh weight loss of earthworms. The earthworm Cd concentration increased with prolonged exposure time, however, the significant immobilization efficacy of amendments observed on the 7th day nearly disappeared after 28 days of exposure. The immobilization efficiencies, estimated by the earthworms internal Cd concentration, of L, H and B on the 7th day were 38.6%, 37.8% and 20.7%, respectively. These values decreased to 4.9%, 19.8% and 15.1%, respectively, on the 28th day. The detoxification effect of amendments was confirmed by the Cd subcellular fractionation in earthworms with lower proportions of Cd distributed in the metal-sensitive fractions in L, H and B treatments. The level of oxidative stress response of earthworms increased with exposure duration and amendments alleviated the oxidative damage induced by Cd to the earthworms. In addition, the pH and CaCl2-Cd in soils were both increased due to earthworm life activities and gut-related ingestion. In summary, the assessment of immobilization effectiveness of heavy metal-contaminated soils using Eisenia fetida was time-dependent. The immobilization efficacy of L and H performed better than B and F on the 7th day, while H and B performed better than L and F on the 28th day. Accordingly, the short-term earthworm exposure experiment (7 days) was recommended to be an alternative approach to time-consuming plant bioassays in assessment of reduced phytoavailability in chemical immobilization remediation. But the impact of earthworms on the immobilization effect of amendments needs to be considered in practical remediation.


Assuntos
Cádmio/análise , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/análise , Animais , Cádmio/toxicidade , Compostos de Cálcio , Carvão Vegetal , Durapatita , Fertilizantes , Oligoquetos/química , Óxidos , Solo/química , Poluentes do Solo/toxicidade
5.
Environ Pollut ; 251: 910-920, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31234257

RESUMO

The toxic sensitivity in different physiological levels of chromium (Cr) contaminated soils with environmentally equivalent concentrations (EEC) was fully unknown. The earthworm Eisenia fetida was exposed to a Cr-contaminated soil at the EEC level (referred to as Cr-CS) to characterize the induced toxicity at the whole body, organ, tissue, subcellular structure and metabolic levels. The results showed that the survival rate, weight and biodiversity of the gut microorganisms (organ) had no significant difference (p > 0.05) between control and Cr-CS groups. Qualitative histopathological and subcellular evaluations from morphology showed earthworms obvious injuries. The organelle injuries combined with the metabolic changes provided additional evidence that the Cr-CS damaged the nucleus and probably disturbed the nucleic acid metabolism of earthworms. 2-hexyl-5-ethyl-3-furansulfonate, dimethylglycine, betaine and scyllo-inositol were sensitive and relatively quantitative metabolites that were recommended as potential biomarkers for Cr-CS based on their significant weights in the multivariate analysis model. In addition, the relative abundance of Burkholderiaceae, Enterobacteriaceae and Microscillaceae of the earthworm guts in the Cr-CS group significantly increased, particularly for Burkholderiaceae (increased by 13.1%), while that of Aeromonadaceae significantly decreased by 5.6% in contrast with the control group. These results provided new insights into our understanding of the toxic effects of the EEC level of Cr contaminated soil from different physiological levels of earthworms and extend our knowledge on the composition and sensitivity of the earthworm gut microbiota in Cr contaminated soil ecosystems. Furthermore, these toxic responses from gut microorganisms to metabolites of earthworms provided important data to improve the adverse outcome pathway and toxic mechanism of the Cr-CS if the earthworm genomics and proteomics would be also gained in the future.


Assuntos
Cromo/toxicidade , Poluição Ambiental/análise , Oligoquetos/metabolismo , Oligoquetos/microbiologia , Poluentes do Solo/toxicidade , Solo/química , Animais , Bacteroidetes/crescimento & desenvolvimento , Burkholderiaceae/crescimento & desenvolvimento , Cromo/análise , Enterobacteriaceae/crescimento & desenvolvimento , Organelas/efeitos dos fármacos , Poluentes do Solo/análise
6.
Environ Sci Pollut Res Int ; 25(23): 23117-23124, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29860691

RESUMO

To explore the main controlling factors in soil and build a predictive model between the lead concentrations in earthworms (Pbearthworm) and the soil physicochemical parameters, 13 soils with low level of lead contamination were used to conduct toxicity experiments using earthworms. The results indicated that a relatively high bioaccumulation factor appeared in the soils with low pH values. The lead concentrations between earthworms and soils after log transformation had a significantly positive correlation (R2 = 0.46, P < 0.0001, n = 39). Stepwise multiple linear regression analysis derived a fitting empirical model between Pbearthworm and the soil physicochemical properties: log(Pbearthworm) = 0.96log(Pbsoil) - 0.74log(OC) - 0.22pH + 0.95, (R2 = 0.66, n = 39). Furthermore, path analysis confirmed that the Pb concentrations in the soil (Pbsoil), soil pH, and soil organic carbon (OC) were the primary controlling factors of Pbearthworm with high pathway parameters (0.71, - 0.51, and - 0.49, respectively). The predictive model based on Pbearthworm in a nationwide range of soils with low-level lead contamination could provide a reference for the establishment of safety thresholds in Pb-contaminated soils from the perspective of soil-animal systems.


Assuntos
Chumbo/metabolismo , Oligoquetos/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Animais , China , Modelos Biológicos
7.
Environ Pollut ; 239: 428-437, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29679940

RESUMO

Mercury is a globally distributed toxicant to aquatic animals and mammals. However, the potential risks of environmental relevant mercury in terrestrial systems remain largely unclear. The metabolic profiles of the earthworm Eisenia fetida after exposure to soil contaminated with mercury at 0.77 ±â€¯0.09 mg/kg for 2 weeks were investigated using a two-dimensional nuclear magnetic resonance-based (1H-13C NMR) metabolomics approach. The results revealed that traditional endpoints (e.g., mortality and weight loss) did not differ significantly after exposure. Although histological examination showed sub-lethal toxicity in the intestine as a result of soil ingestion, the underlying mechanisms were unclear. Metabolite profiles revealed significant decreases in glutamine and 2-hexyl-5-ethyl-3-furansulfonate in the exposed group and remarkable increases in glycine, alanine, glutamate, scyllo-inositol, t-methylhistidine and myo-inositol. More importantly, metabolic network analysis revealed that low mercury in the soil disrupted osmoregulation, amino acid and energy metabolisms in earthworms. A metabolic net link and schematic diagram of mercury-induced responses were proposed to predict earthworm responses after exposure to mercury at environmental relevant concentrations. These results improved the current understanding of the potential toxicity of low mercury in terrestrial systems.


Assuntos
Mercúrio/toxicidade , Metaboloma/efeitos dos fármacos , Oligoquetos/fisiologia , Poluentes do Solo/toxicidade , Animais , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Mercúrio/análise , Metabolômica , Oligoquetos/efeitos dos fármacos , Oligoquetos/metabolismo , Solo/química , Poluentes do Solo/análise
8.
Sci Rep ; 7(1): 13110, 2017 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-29026156

RESUMO

To characterize the potential toxicity of low Pb- and Cd-contaminated arable soils, earthworms were exposed to Pb contaminated ferrosol, cambosol or Cd contaminated ferrosol for two weeks. Polar metabolites of earthworms were detected by nuclear magnetic resonance. Data were then analyzed with principal component analysis followed by orthogonal signal correction-partial least squares-discriminant analysis and univariate analysis to determine possible mechanisms for the changes in metabolites. The survival rates, metal concentrations and bioaccumulation factor (BAF) of the earthworms were also measured and calculated as auxiliary data. The results showed that the metabolite profiles were highly similar in Pb-contaminated ferrosol and cambosol (R2 = 0.76, p < 0.0001), which can be attributed to similar response mechanisms. However, there was a more intense response in ferrosol likely due to higher Pb concentrations in earthworms. Metabolic pathways and BAFs exhibited apparent distinctions between Pb- and Cd-contaminated ferrosol, likely because they bind to different bio-ligands. The affected metabolic pathways were involved in alanine-aspartate-glutamate, purine, glutathione, valine-leucine-isoleucine biosynthesis and degradation and nicotinate and nicotinamide metabolism. Regarding the bioavailability in earthworms, Pb availability was higher for ferrosol than for cambosol. We confirmed that the potential toxicity of low Pb/Cd-contaminated soils can be characterized using earthworm metabolomics.


Assuntos
Cádmio/metabolismo , Chumbo/metabolismo , Oligoquetos/metabolismo , Poluentes do Solo/metabolismo , Animais , Poluição Ambiental , Metabolômica/métodos , Solo
9.
Environ Sci Pollut Res Int ; 22(15): 11658-68, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25850747

RESUMO

An intensive investigation was conducted to study the spatial distribution and temporal variety trend of mercury and arsenic in plant tissue and soil profile in the eastern of the Tibet Plateau and to explore the possible sources of these two elements. At present, rare information is available on mercury (Hg) and arsenic (As) of timberline forests in the Tibet Plateau. Here, we present preliminary results on these two elements in leaves, twigs, root, litterfall, and soil. Geostatistical analyst of the ArcGIS 10.0 was used to determine the trait of spatial distribution of these two elements. Total arsenic (TAs) mean concentrations in the leaves, twigs, root, litterfall, and A- and C-layer soil ranged from 0.12 mg kg(-1) (n = 60), 0.35 mg kg(-1) (n = 60), 0.48 mg kg(-1) (n = 42), 1.52 mg kg(-1) (n = 84), 16.51 mg kg(-1) (n = 69), and 26.72 mg kg(-1) (n = 69), respectively. Total Hg (THg) mean concentrations in leaves, twigs, root, litterfall, and A- and C-layer soil were 0.0121 mg kg(-1) (n = 60), 0.0078 mg kg(-1) (n = 60), 0.0171 mg kg(-1) (n = 42), 0.0479 mg kg(-1) (n = 84), 0.0852 mg kg(-1) (n = 75), and 0.0251 mg kg(-1) (n = 75), respectively. In general, litterfall trended to accumulate high concentrations of Hg and As. Mercury in the timberline forest showed an increasing trend, whereas arsenic concentrations showed a decreasing trend in A-layer soil and an increasing trend in C-layer soil due to the easy mobile ability of As. Southwest and southeast monsoon could be the influencing factors, and Hg emission from India and China was the possible source of this study area through using a HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model. It is believed that these observations may offer scientists and policymakers additional understanding of Hg and As concentrations in the remote timberline area, eastern of the Tibet Plateau.


Assuntos
Arsênio/análise , Monitoramento Ambiental , Florestas , Mercúrio/análise , Solo/química , Análise Espaço-Temporal , Traqueófitas , Folhas de Planta/química , Raízes de Plantas/química , Poluentes do Solo/análise , Tibet
10.
Ecotoxicology ; 23(6): 1086-98, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24817526

RESUMO

Concentrations of 14 heavy metals (Ag, As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Tl, V, and Zn) in needles, twigs, bark and xylem of spruce and fir collected at the timberline of eight sites along the Hengduan Mountains, eastern Tibetan Plateau, are reported. Twigs had the highest concentration for most of elements, while xylem had the lowest concentration. The connections between elements in twigs were much richer than other organ/tissues. Pb, Ni, As, Sb, Co, Cd, Hg, Cr and Tl which are partly through anthropogenic sources and brought in by monsoon, have been accumulated in twigs and needles by wet or dry deposition in south and east sites where are within or near pollutant sources. Under moderate pollution situation, vegetation are able to adjust the nutrient element (Cu and Zn) cycle rate, thus maintain a stable concentration level. Seldom V, Ag, and Mo are from external anthropogenic sources. Needles and twigs can be used as biomonitors for ecosystem environment when needles can simply distinguish the origin of elements and twigs are more sensitive to extra heavy metal input.


Assuntos
Abies/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/análise , Metais Pesados/análise , Picea/metabolismo , Poluentes Ambientais/metabolismo , Metais Pesados/metabolismo , Tibet
11.
Environ Sci Process Impacts ; 15(10): 1930-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24056779

RESUMO

In order to study the regional distribution, trait and possible source of chromium in the eastern Tibetan Plateau, we collected samples of xylem, bark, leaves and twigs in two parallel northwest-southeast belt transects (TA and TB) from the Hengduan Mountains. According to the Cr mean concentration, organ/tissue was split into two groups: the high-level organ/tissue (twigs: 1.476 mg kg(-1)) and the low-level organ/tissue (bark: 0.413 mg kg(-1), leaves: 0.340 mg kg(-1) and xylem: 0.194 mg kg(-1)). The mean Cr concentrations of twigs and leaves in TB samples were higher than those in the TA samples, and the mean Cr concentration in both sites gradually reduced from southeast to northwest. Both the southeasterly and southwesterly monsoons could be significant, influential factors in this connection. The top three mean Cr concentrations were S7, S1 and S8, which were closer to the developed city. Mean Cr concentrations in S3, S4 and S5, (remote, high mountains) were relatively low. The high mountains acting as a barrier to the monsoon and the distance from the big city may play important roles in the distribution of Chromium. Furthermore, the relationship between the mean Cr concentration and precipitation, timberline trees as bio-monitors of chromium pollution in polluted areas and the possible source of Cr in the eastern Tibetan Plateau are also discussed. This study may provide reliable proof of Cr contamination processes, and so help in future to prevent further Cr pollution, and also be helpful in understanding the important function of forest ecosystems in relation to atmospheric pollution and global change. To better understand the characteristics of temporal and spatial distribution of Cr concentration, we found that tree ring, fine roots and soil samples are good choices.


Assuntos
Cromo/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Componentes Aéreos da Planta/química , Árvores/química , Altitude , Componentes Aéreos da Planta/crescimento & desenvolvimento , Tibet , Árvores/crescimento & desenvolvimento
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