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1.
J Environ Sci (China) ; 143: 138-147, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38644012

RESUMO

Tetramethylammonium hydroxide (TMAH) is an important compound that utilized and released by the rapidly expanding semiconductor industry, which could hardly be removed by the conventional wastewater treatment techniques. As a cholinergic agonist, the tetramethylammonium ion (TMA+) has been reported to induce toxicity to muscular and respiratory systems of mammals and human, however the toxicity on aquatic biota remains poorly known. We investigated the neurotoxic effects of TMA+ exposure on zebrafish, based on neurobehavior tests and a series of biomarkers. Significant inhibitions on the swimming distance of zebrafish larvae were observed when the exposure level exceeded 50 mg/L, and significant alterations on swimming path angles (straight and deflective movements) occurred even at 10 mg/L. The tested neurobehavioral endpoints of zebrafish larvae were significantly positively correlated with reactive oxygen species (ROS) and malondialdehyde (MDA), significantly negatively related with the activities of antioxidant enzymes, but not significantly correlated with the level of acetylcholinesterase (AChE). Such relationship indicates that the observed neurotoxic effects on swimming behavior of zebrafish larvae is mainly driven by oxidative stress, rather than the alterations of neurotransmitter. At the highest exposure concentration (200 mg/L), TMA+ evoked more severe toxicity on zebrafish juveniles, showing significantly stronger elevation on the MDA activity, and greater inhibitions on the activities of antioxidant enzymes and AChE, suggesting juveniles were more susceptible to TMA+ exposure than larval zebrafish.


Assuntos
Biomarcadores , Larva , Compostos de Amônio Quaternário , Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Poluentes Químicos da Água/toxicidade , Biomarcadores/metabolismo , Compostos de Amônio Quaternário/toxicidade , Larva/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Natação , Comportamento Animal/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
2.
Sci Total Environ ; 929: 172541, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38642747

RESUMO

Volatile methylsiloxanes (VMSs) earned serious concerns due to their detection and toxicities after their release to the environments. They were also detected in rivers around the globe, but their distribution remained to be explored in larger rivers with longer length, higher water volume and wider watershed. In the present study, 8 cyclic VMSs (cVMSs) and 7 linear ones (lVMSs) were investigated in 42 water samples (27 surface water (including 7 drinking source water) and 15 wastewater) from the Yangtze River Basin, China. Results showed that VMSs were detected in all sampling sites. In surface water, the concentrations of total cVMSs ranged from 17.3 to 4.57 × 103 ng/L, while those of lVMSs ranged from 1.72 to 81.6 ng/L. In wastewater, the total concentrations of cVMSs and lVMSs showed ranges of 17.6-1.66 × 103 ng/L and 2.59-252 ng/L, respectively. Apparently, cVMSs showed significantly higher concentrations than lVMSs. The concentrations of cVMSs followed an order of lower > upper > middle reaches, while those of lVMSs did not show clear distribution patterns. Among cVMSs, those with less Si numbers were dominant, while those with more Si numbers were dominant in lVMSs. Notably, the VMSs were also detected in 7 surface waters that served as drinking source waters, which earned them further concerns. In addition, the VMSs in surface water showed positive correlation with those in wastewater, which led to necessity in management on industrial emissions in the future.

3.
J Hazard Mater ; 452: 131253, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36966626

RESUMO

This study conducted a comprehensive investigation on the distribution and bioavailability of heavy metals (Cr, Co, Ni, Cu, Zn, Cd and Pb) in sediments along two typical transects from Yangtze River to the East China Sea continental shelf that spanning large physicochemical gradients. Heavy metals were mainly associated with the fine-grained sediments (enriched with organic matter), exhibiting decreasing trends from nearshore to offshore sites. The turbidity maximum zone showed the highest metal concentrations, which evaluated as polluted for some tested metals (especially Cd) using the geo-accumulation index. Based on the modified BCR procedure, the non-residual fractions of Cu, Zn and Pb were higher within the turbidity maximum zone, and significantly negatively correlated with bottom water salinity. The DGT-labile metals all positively correlated with the acid-soluble metal fraction (especially for Cd, Zn and Cr), and negatively correlated with salinity (except Co). Therefore, our results suggest salinity as the key factor controlling metal bioavailability, which could further modulate metal diffusive fluxes at the sediment-water interface. Considering that DGT probes could readily capture the bioavailable metal fractions, and reflect the impacts of salinity, we suggest DGT technique can be used as a robust predictor for metal bioavailability and mobility in estuary sediments.

4.
Bull Environ Contam Toxicol ; 109(2): 358-363, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35247065

RESUMO

The hydraulic conductivity of Na-montmorillonite in dual-cation solutions of Na+ and Mn+ (Mn+ = K+, Ca2+, Zn2+ and Al3+) with a constant ionic strength of 0.1 mol/L was determined. The focus of this study was on the influence of Mn+ on the grain-size distribution of montmorillonite and hence its hydraulic conductivity. All the tested cations showed a high affinity towards montmorillonite, and the high valency favored the exchange between Mn+ and Na+. The hydraulic conductivity of montmorillonite increased to the maxima and then decreased in a left-skewed log-normal shape as the cation exchange progressed. The grain size of montmorillonite concurrently decreased monotonically with the cation exchange. The XRD patterns of montmorillonite confirmed the occurrence of demixing of Na+ and K+ in the interlayers. It is proposed that the rearrangement and reaggregation of grains during cation exchange occurred, leading to variations in the hydraulic conductivity of montmorillonite.


Assuntos
Bentonita , Sódio , Adsorção , Cátions
5.
Environ Sci Pollut Res Int ; 28(40): 56392-56400, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34050911

RESUMO

Understanding of the plant uptake of ionizable organic compounds is critical to the evaluation of crop contamination, plant protection, and phytoremediation. This study investigated the time-dependent uptake of 2,4-dichlorophenol (DCP) by intact wheat seedling roots and subsequent translocation to shoots at pH 5.0 and 8.0. Sorption of DCP by cut roots and shoots at these two pHs was conducted to provide the uptake limits and the Donnan charge. For comparison, sorption was also conducted for 1,3-dichlorobenzene (DCB), a nonionizable compound having a structure similar to that of DCP. The DCB sorption isotherms were linear and independent of pH, yielding a consistent log Klip of 3.56 with both roots and shoots, reflective of the essential dominant role of lipids in plant partition uptake. Whereas the DCP sorption also showed a linear isotherm at pH 5.0 with log Klip = 2.88, the sorption at pH 8.0 was nonlinear with a concave downward shape, especially at low concentrations. With live wheat seedlings, the DCB uptake by roots and the DCB translocation to shoots rapidly approached a steady state, showing no obvious pH effect. On the DCP uptake by live plants, there was a rapid attainment of a steady state in roots at pH 5.0 coupled with a retarded transport to shoots due presumably to the polarity of DCP. At pH 8.0, the root uptake of DCP was comparatively slower and the translocation to shoots was completely inhibited due presumably to DCP ionization. At high pH, DCP was supposedly accumulated in an ionized form in root cells via an ion-trapping mechanism.


Assuntos
Clorofenóis , Plântula , Raízes de Plantas , Triticum
6.
Ecotoxicol Environ Saf ; 219: 112374, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34049226

RESUMO

This study determined the degradation of lindane in soil amended with biochar to evaluate the effects of biochar aging and microbial toxicity. Two biochars were prepared at 400 and 600 °C (BC400 and BC600) and subjected to acid washing to remove nutrition (WBC400 and WBC600). After 89 days of incubation under the alternate "wet-dry" conditions, scanning electron microscopy showed that acid washing rendered biochars especially susceptible to aging with structural collapse and fragmentation, with less surface covering. Aging impeded the release of toxic substances in BC400 and BC600 with reduced toxicity to degrading microorganisms. Lindane degradation was somewhat stimulated by biochar nutrition but mainly inhibited by adsorption. Acid washing facilitated the release of toxic substances and additionally reduced lindane degradation. The variations in fatty acid saturation degree (SFA/UFA) in soils confirmed the microbial toxicity of 5% WBC400 > 5% BC400 > 5% BC600 > 5% WBC600. High-throughput DNA sequencing showed that biochar delayed the formation of dominant degrading microbial communities in soil. Lindane degradation was completed by joint Sphingomonas, Flaviolibacter, Parasegetibacter, Azoarcus, Bacillus and Anaerolinaea. These findings are helpful for better understanding the effect of biochar in soil on long-term degradation of persistent organic pollutants.


Assuntos
Carvão Vegetal/química , Hexaclorocicloexano/metabolismo , Poluentes do Solo/metabolismo , Adsorção , Biodegradação Ambiental , Solo/química , Poluentes do Solo/análise
7.
Chemosphere ; 281: 130883, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34023758

RESUMO

Soil flushing is one of the common in-situ remediation technologies, in which the permeability of the soil determines its feasibility. Batch extractions showed that deionized water extracted about 20% Cu and 30% Cd from a soil. Electrolytes of 100 mmol/l NaCl, 500 mmol/l NaCl, and 167 mmol/l CaCl2 promoted the extractions to about 60% and 90%, respectively, with higher concentration and valence of cations being more effective. Presence of 100 mmol/l EDTA as a chelant further enhanced the extractions to near completion. Extractions appeared to occur concurrently via ion exchange, complexation with Cl- and predominantly chelation with EDTA. Column leaching in dynamic setups with electrolyte solutions in the presence of EDTA showed similar Cu and Cd removal degrees to the batch extractions. The permeability of soils during leaching decreased by up to 80%, decelerating time-dependent Cu and Cd removal, due to soil swelling by Na+. Electrolytes in leaching solutions well defended the permeability of soil against its decrease to as low as 3.5%, maintaining Cu and Cd removal rates. Formulating flushing solution with EDTA and proper electrolytes have advantages of not only enhancing extraction degrees but accelerating heavy metal removal from soil by regulating the permeability, with the potential to be extended to soils with high clay contents and thus low natural permeability.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio , Ácido Edético , Eletrólitos , Metais Pesados/análise , Permeabilidade , Solo , Poluentes do Solo/análise
8.
Water Sci Technol ; 83(9): 2075-2086, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33989177

RESUMO

Shortcomings of individual biochar or microbial technologies often exist in heavy metal removal from wastewater and may be circumvented by coupled use of biochar and microorganisms. In this study, Bacillus subtilis and each of three biochars of different origins (corn stalk, peanut shell, and pine wood) were coupled forming composite systems to treat a cadmium (Cd, 50 mg/L) wastewater formulated with CdCl2 in batch tests. Biochar in composite system enhanced the activity and Cd adsorption of B. subtilis. Compared with single systems with Cd removal up to 33%, the composite system with corn stalk biochar showed up to 62% Cd removal, which was greater than the sum of respective single B. subtilis and biochar systems. Further analysis showed that the removal of Cd by the corn stalk composite system could be considered to consist of three successive stages, that is, the biochar-dominant adsorption stage, the B. subtilis-dominant adsorption stage, and the final biofilm formation stage. The final stage may have provided the composite system with the ability to achieve prolonged steady removal of Cd. The biochar-microorganism composite system shows a promising application for heavy metal wastewater treatment.


Assuntos
Cádmio , Águas Residuárias , Adsorção , Bacillus subtilis , Cádmio/análise , Carvão Vegetal
9.
Chemosphere ; 278: 130474, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33839397

RESUMO

Blockage of nanoparticles on plant pore structures might produce phytotoxicity and affect plant uptake indirectly. This study examined the blocking and phytotoxic effects of fullerene nanoparticles (nC60) on plants at the cellular level. The malondialdehyde content in plant was normal during nC60 exposure, implying that nC60 caused no acute phytotoxicity, while the normalized relative transpiration significantly decreased, showing that the pore structure of roots was seriously blocked by nC60. High power optical microscopy and transmission electron microscope showed that root endothelial cells were squeezed, and inner wall structures were damaged by the extrusion of nanoparticles. Low nC60 concentrations inhibited root uptake of lindane, whereas high nC60 concentrations promoted root uptake of lindane, indicating that serious pore blocking by nC60 damaged root cell structure and hence ready transport of lindane from roots to shoots. Significant alterations of fatty acid (FA) saturation degree of root cell membrane indicated that nC60 led to phytotoxicity in the root cell membrane after long-term exposure and nC60 produced phytotoxicity in the process of blocking root pore structures and interfering with cell membrane fluidity. Moreover, the plant cell structures under phytotoxicity were more likely to be damaged mechanically by the extrusion of nanoparticles. These findings may be helpful to better understand the transport pathways of nanoparticles in plants, the phytotoxicity of nanoparticles and the potential risks of nanomaterials used in agriculture.


Assuntos
Fulerenos , Nanopartículas , Células Endoteliais , Fulerenos/toxicidade , Malondialdeído , Nanopartículas/toxicidade , Células Vegetais , Raízes de Plantas
10.
Chemosphere ; 275: 130021, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33647678

RESUMO

Surface oxygen-containing functional groups (OFGs) at different sites of carbonaceous materials showed different effects on the normalized monolayer adsorption capacity (QBET/A) obtained from the modified BET model. The OFGs on mesoporous surfaces inhibited the adsorption via the water competition, whereas those on the external surface promoted the adsorption due to the enhanced hydrophobic driving force and electrostatic forces, as analyzed from the adsorption molar free energy. Multiple linear relationships were established between the monolayer adsorption capacity QBET/A and the amounts of OFGs on mesoporous and the external surfaces ([O]meso and [O]external, respectively). The properties of aromatic adsorbate compounds, the polar area radio of aromatic molecule to water (PAad/w), and the log Kow together influenced the inhibition or promotion effects of OFGs. These results would allow predictions of adsorption behavior of aromatic compounds on carbonaceous materials on the basis of OFGs parameters. Theoretical calculations and simulations projected the configuration of aromatic molecules being parallel to the graphene sheets of carbonaceous materials. The symmetry-adapted perturbation theory (SAPT) energy decomposition showed that the electrostatic forces intensified with the increase of adsorbate polarity. These analyses revealed that the electrostatic forces were enhanced in the presence of OFGs and that the π-π EDA (electron donor-acceptor) was the main force.


Assuntos
Grafite , Oxigênio , Adsorção , Interações Hidrofóbicas e Hidrofílicas , Compostos Orgânicos
11.
Chemosphere ; 262: 127831, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32791367

RESUMO

The study was conducted to investigate the influence of the culture pattern on plant uptake and translocation of an organic chemical and the resultant acute response of plants, and to further reveal the interconnection. Plant exposure experiments were performed using a conventional rice seedling (Oryza sativa L. subsp. indica) under two kinds of culture patterns (viz., hydroponics and soil-based culture) with various culture matrices for a period of 7 days. The exposure concentration of lindane was ∼450 µg L-1 in the aqueous-phase matrices, and 200.1-756.0 µg kg-1 in the solid matrices. Lindane accumulation and its distribution in plant tissues were quantified, as well as the tissue biomass. The results showed the accumulation of lindane in all exposure groups were comparatively close over the period, confirming that the soil-bound lindane was scarcely available to plants. Similar trend of lindane uptake and translocation in seedlings was found among the groups under the same kind of cultivation pattern. In the hydroponic groups, lindane was mostly distributed in roots (about 60% at the end of exposure), whereas more lindane was translocated to shoots (approximate 70%) under the soil-based culture pattern. Allometric analysis demonstrated that the tissue part (root or shoot) with more lindane accumulation had a relatively higher growth rate over 7 days. Correspondingly, biomass allocation presented a slight trend of mutual proximity to lindane distribution. It was inferred that plants altered their allometric growth pattern to realize biomass re-allocation in response to the short-term lindane exposure, which could be considered as a plant defense strategy.


Assuntos
Hexaclorocicloexano/metabolismo , Oryza/metabolismo , Poluentes do Solo/metabolismo , Transporte Biológico , Biomassa , Hidroponia , Oryza/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Solo , Poluentes do Solo/análise
12.
Environ Pollut ; 264: 114689, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388302

RESUMO

Growing evidence suggests that microplastics can adsorb antibiotics and may consequently exacerbate effects on the health of exposed organisms. Our current understanding of the combined effects of microplastics and antibiotics on antibiotic resistance genes (ARGs) in soil invertebrates is limited. This study aimed to investigate changes in the microbiome and ARGs in Enchytraeus crypticus following exposure to a soil environment that contained both microplastics and antibiotics. Tetracycline (TC), polyamide (PA) and polyvinyl chloride (PVC) were used to construct microcosms of polluted soil environments (TC, PA, PVC, PA+TC, PVC+TC). The differences in microbiomes and ARGs were determined by bacterial 16S rRNA gene amplicon sequencing and high throughput quantitative PCR. The results show that compared with the Control or microplastics alone treatments, TC was significantly accumulated in E. crypticus when exposed to TC alone or in combination with microplastics (P < 0.05), but there were no significant differences about TC accumulation between TC, PA+TC, and PVC+TC treated E. crypticus (P > 0.05). Microplastics and TC significantly disturbed the microbial community, and decreased the microbial alpha diversity of E. crypticus (P < 0.05). However, there were no significant differences between TC, microplastics and their combined exposure treatments, and no toxic synergies on the diversity of E. crypticus microbiome between tetracycline and microplastics in soil environment. All the treatments increased the diversity of ARGs in E. crypticus (39-49 ARGs vs. 25 ARGs of control). In particular, treatments combining PVC and TC or PA and TC exposure resulted in greater ARGs abundance than the treatments when E. crypticus was exposed to PVC, PA or TC alone. These results add to our understanding of the combined effects of microplastics and antibiotics on the ARGs and microbiome of soil invertebrates.


Assuntos
Microbiota , Solo , Animais , Antibacterianos , Resistência Microbiana a Medicamentos , Genes Bacterianos , Microplásticos , Plásticos , RNA Ribossômico 16S , Microbiologia do Solo
13.
Environ Int ; 141: 105778, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32416373

RESUMO

Although increased contact time (aging) of pesticides in the soil decreases their bioavailability, this does not mean that the bound residues formed during the aging process pose fewer risk to the soil environment. Here the earthworm Eisenia fetida was exposed to organochlorine pesticide lindane in soil under different durations of lindane aging and exposure. The results of de novo RNA sequencing followed by molecular and biochemical validations demonstrated the aged lindane showed a different tendency to disrupt acetylcholine (ACh) transmission with the effects of fresh lindane to gamma-aminobutyric acid. Using own-developed earthworm activity test, we confirmed aged lindane prompted earthworms to exclusively exhibit a significant hypoactivity in locomotion, which could be explained by the inhibition of Ach system. This study suggested that the toxicity of pesticides would not depend solely on their free state components, and the awareness of long-term environmental risks from the bound states needs to be raised.


Assuntos
Oligoquetos , Praguicidas , Poluentes do Solo , Animais , Hexaclorocicloexano/análise , Hexaclorocicloexano/toxicidade , Praguicidas/toxicidade , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
14.
Ecotoxicol Environ Saf ; 192: 110289, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061990

RESUMO

Comparatively limited knowledge is known about the accumulation processes of tributyltin (TBT) and triphenyltin (TPT) in fish and aquatic plant in the freshwater environment, which has hindered a full understanding of their bioaccumulation potential and ecological risks. In the present study, sorption of TBT and TPT on dead biota of both carp and C. demersum from water via the batch equilibrium technique as well as uptake of them on live biota of both carp and C. demersum from water at a static and a dynamic kinetics tests were investigated, respectively. Both TBT and TPT exhibit a high affinity in carps and C. demersum. And C. demersum has a faster metabolism either for TBT or TPT than carp. The apparent uptake values (Cbio = 1904-8831 µg/kg) or bioconcentration factor (BCF = 3333-44000 L/kg) were one or two orders of magnitude higher than that of estimated by a simple sorption (405-472 µg/kg) or lipid model (74.5-149.6 µg/kg) for carp, indicating the uptake of TBT and TPT did not only depend on lipids but also oxygen ligands or macromolecules such as amino acids and proteins of the living organism. In contrast, the apparent Cbio values (149.1-926.4 µg/kg) of both TBT and TPT were lower than that of estimated by sorption model (1341-1902 µg/kg) for C. demersum, which were due to the rapid metabolic rate of them, especially for TBT. But no relation was observed between TBT and TPT concentrations and lipid contents in C. demersum.


Assuntos
Compostos Orgânicos de Estanho/farmacocinética , Compostos de Trialquitina/farmacocinética , Poluentes Químicos da Água/farmacocinética , Animais , Carpas/metabolismo , Cinética , Magnoliopsida/metabolismo
15.
Chemosphere ; 249: 126113, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32062208

RESUMO

The widespread occurrence and distribution of organotin compounds (OTCs) in both marine and freshwater ecosystems has aroused considerable concerns in most countries worldwide. In this work, individual kinetics of the elimination of three butyltins and three phenyltins from C. demersum L. were systematically studied for over 240 h in clean water after a 48h period of accumulation. All OTCs were rapidly metabolized to nontoxic inorganic tin by C. demersum L. through stepwise debutylation or dephenylation. In addition to inorganic tin, monobutyltin (MBT) and monophenyltin (MPT) were the primary degradation products of tributyltin (TBT) and triphenyltin (TPT), with small amounts of dibutyltin (DBT) and diphenyltin (DPT), respectively, also being present. The estimated half-life of TPT (240 h) in C. demersum L. was longer than that of TBT (100 h), although the TPT was less hydrophobic. The corresponding degradation mechanisms may be attributed to a cascade of enzymatic reactions of CYP450 enzymes in C. demersum L. The pH played an important role in both plant growth and TBT degradation. Although pH 8.9 was more suitable for C. demersum L. growth, it uptook and metabolized more TBT at pH 5.0, which may be because the cationic species TBT+ (at pH 5.0) was metabolized more easily than the neutral hydroxide species TBTOH (at pH 8.9). C. demersum L. may thus be the plant with the most potential for the remediation of OTC-contaminated freshwater environments.


Assuntos
Magnoliopsida/metabolismo , Compostos Orgânicos de Estanho/metabolismo , Poluentes Químicos da Água/metabolismo , Ecossistema , Água Doce , Compostos de Trialquitina , Poluentes Químicos da Água/análise
16.
Sci Total Environ ; 715: 136966, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32040999

RESUMO

The outdated test methodologies for terrestrial animals have limited the progress of soil ecotoxicology to some extent. To improve the behavioral testing of earthworms, a terrestrial model animal, a sensitive optical-based method for detecting locomotor activity was established. The method measured the fine quantified position offsets of each earthworm in place of a conventional overall response rate, which provided the feasibility for accurate analyses and comparisons. By setting appropriate thresholds, the time proportions of medium and burst states (mid-burdur%) could be an optimized endpoint with an ideal balance in output stability and sensitivity. In addition, we chose the head-end, which is the most flexible part of the earthworm, other than whole body to further elevate the sensitivity in indicating the changed traits. Using octopamine, serotonin, and a serial-dose of lindane exposure, the practice credibility of the test method was validated. Our developed locomotor test method overcame the innate characteristics of the earthworm, and was expected to provide a powerful phenotypic tool for ecological and ecotoxicological studies using earthworms and similar invertebrates.


Assuntos
Oligoquetos , Animais , Ecotoxicologia , Locomoção , Solo , Poluentes do Solo
17.
J Hazard Mater ; 387: 122012, 2020 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-31927355

RESUMO

It has been proved that nanoplastics can effectively adsorb pollutants and thus influence their behavior and availability. The combined toxic effects of nanoplastic and its adsorbed pollutant on the soil fauna are still not well known. We used high-throughput quantitative PCR to explore the effects of oral nanoscale polystyrene and tetracycline exposure on antibiotic resistance genes in the soil invertebrate Enchytraeus crypticus, and used bacterial 16S rRNA gene amplification sequencing to examine the response of the microbiome of E. crypticus. After 14 days of tetracycline and nanoscale polystyrene exposure, we terminated exposure and monitored the restoration of ARGs and microbiome in the E. crypticus. Results showed that the number of ARGs, especially macrolide-lincosamide-streptogramin B (MLSB), tetracycline ARGs, as well as multidrug ARGs, increased with exposure to nanoscale polystyrene and tetracycline. The abundance of Aminoglycoside and Beta_Lactamase ARGs in E. crypticus also significantly increased. The exposure significantly perturbed the abundance of families Microbacteriaceae, Streptococcaceae, Enterobacteriaceae, Rhodocyclaceae and Sphinomonadaceae. After terminating exposure for 14 days, the diversity and abundance of ARGs were not completely restored, while the microbiome was not permanently changed but reversibly impacted.


Assuntos
Antibacterianos/toxicidade , Farmacorresistência Bacteriana/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Poliestirenos/toxicidade , Poluentes do Solo/toxicidade , Tetraciclina/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Microbioma Gastrointestinal/genética , Genes Bacterianos/efeitos dos fármacos , Nanoestruturas/toxicidade , Oligoquetos/microbiologia
18.
Environ Pollut ; 256: 113463, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677875

RESUMO

Growing evidence suggests that metallic oxide nanoparticles can pose a severe risk to the health of invertebrates. Previous attention has been mostly paid to the effects of metallic oxide nanoparticles on the survival, growth and physiology of animals. In comparison, the effects on gut microbiota and incidence of antibiotic resistance genes (ARGs) in soil fauna remain poorly understood. We conducted a microcosm study to explore the responses of the non-target soil invertebrate Enchytraeus crypticus gut microbiota and resistomes to copper oxide nanoparticles (CuO NPs) and copper nitrate by using bacterial 16S rRNA gene amplicons sequencing and high throughput quantitative PCR. The results showed that exposure to Cu2+ resulted in higher bioaccumulation (P < 0.05) and lower body weight and reproduction (P < 0.05) of Enchytraeus crypticus than exposure to CuO NPs. Nevertheless, exposure to CuO NPs for 21 days markedly increased the alpha-diversity of the gut microbiota of Enchytraeus crypticus (P < 0.05) and shifted the gut microbial communities, with a significant decline in the relative abundance of the phylum Planctomycetes (from 37.26% to 19.80%, P < 0.05) and a significant elevation in the relative abundance of the phyla Bacteroidetes, Firmicutes and Acidobacteria (P < 0.05). The number of detected ARGs in the Enchytraeus crypticus gut significantly decreased from 45 in the Control treatment to 16 in the Cu(NO3)2 treatment and 20 in the CuO NPs treatment. The abundance of ARGs in the Enchytraeus crypticus gut were also significantly decreased to 38.48% when exposure to Cu(NO3)2 and 44.90% when exposure to CuO NPs (P < 0.05) compared with the controls. These results extend our understanding of the effects of metallic oxide nanoparticles on the gut microbiota and resistome of soil invertebrates.


Assuntos
Cobre/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Oligoquetos/fisiologia , Poluentes do Solo/toxicidade , Animais , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Microbioma Gastrointestinal/fisiologia , Microbiota/efeitos dos fármacos , Nitratos , Oligoquetos/efeitos dos fármacos , Oligoquetos/microbiologia , RNA Ribossômico 16S , Solo , Poluentes do Solo/análise
19.
Eur Rev Med Pharmacol Sci ; 23(24): 10931-10941, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31858561

RESUMO

OBJECTIVE: High mobility group box1(HMGB1) can be used as PAMP or alarmins to stimulate the innate immune system; however, previous research on immune thrombocytopenic purpura (ITP) mainly focused on its adaptive immunity. The study aimed to determine whether HMGB1 is associated with chronic ITP (cITP) during childhood and investigate its role in innate immunity in childhood cITP. PATIENTS AND METHODS: We recruited 80 patients to measure the expression of HMGB1, IL-17, and IL-10; 55 patients were recruited to measure the expression of TLR2 and TLR4 in monocyte and CD1c+dendritic cells, and 30 volunteers were included as controls. We focused on the expression of the NLRP3 inflammasome during childhood cITP. Furthermore, the impact of HMGB1 on the NLRP3 inflammasome was explored. RESULTS: The expressions of HMGB1 and IL-17 increased in children with cITP, while that of IL-10 decreased; HMGB1 was correlated with the expression of IL-17 and IL-10. The expression of TLR2 in CD14++CD16+, CD14+CD16++ monocytes increased significantly in comparison with the controls; the contrary was observed regarding TLR4. The expression of NLRP3, IL-1ß, and IL-18 was significantly higher in CD14 and CD1c, respectively. As the concentration of HMGB1 increased, the expression of NLRP3, IL-1ß, and IL-18 increased in different degrees. CONCLUSIONS: HMGB1 could be used as an early warning alarm for childhood cITP and is involved in developing cITP. HMGB1 could affect the incidence and development of chronic childhood ITP via the NLRP3, TLR2/TLR4 pathways.


Assuntos
Proteína HMGB1/imunologia , Púrpura Trombocitopênica Idiopática/imunologia , Células Cultivadas , Criança , Doença Crônica , Feminino , Proteína HMGB1/genética , Humanos , Imunidade Inata/imunologia , Masculino , Púrpura Trombocitopênica Idiopática/genética
20.
Environ Sci Pollut Res Int ; 26(23): 24223-24234, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31230245

RESUMO

Elucidation of the interaction between NACs and smectites is important to the understanding of the potential for transport of nitroaromatic compounds (NACs) in soils and to implementation of NAC-contaminated soil remediation. The adsorption of dinitrotoluene isomers (DNTs) and substituted dinitrobenzenes (SDNBs) by smectite was determined by batch equilibration and characterized by FTIR and XPS, along with molecular dynamics simulations. The adsorption of DNTs differed substantially among the isomers, attributed to the overall degree of nitro deflection relative to the aromatic ring plane. The substituents in SDNBs strengthened the electrostatic interaction between smectite K+ and nitro groups, facilitating SDNB adsorption to smectite. The competition between 2,4-DNT and 1,3-DNB, as well as the inclusion complexation of K+ by crown ether 18c6e, both reduced 2,4-DNT adsorption to smectite by weakening the K+-nitro interaction. All the results demonstrated that the electrostatic interaction between smectite K+ and nitro of NACs was the predominant force in mediating their adsorption. This was supported by FTIR spectra that the N-O bands shifted due to the weakening of N-O bonds and strengthening of C-N bonds via the electron transfer to cations. The XPS of smectite further manifested the cation-nitro interactions that the binding energies of K 2p 1/2, K 2p 3/2, and Si 2p shifted higher with 1,3-DNB adsorbed. Molecular dynamics simulations indicated the aromatic planes of 2,4-DNP and 2,4-DNAs were parallel to the basal plane of smectite and the oxygens of nitro groups in the molecules were directly coordinated with smectite K+.


Assuntos
Dinitrobenzenos/química , Silicatos/química , Poluentes do Solo/química , Adsorção , Cátions/química , Argila , Modelos Químicos , Solo
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