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1.
Rev Environ Contam Toxicol ; 249: 1-27, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30725190

RESUMO

Metals are major abiotic stressors of many organisms, but their toxicity in plants is not as studied as in microorganisms and animals. Likewise, research in plant responses to metal contamination is sketchy. Candidate genes associated with metal resistance in plants have been recently discovered and characterized. Some mechanisms of plant adaptation to metal stressors have been now decrypted. New knowledge on microbial reaction to metal contamination and the relationship between bacterial, archaeal, and fungal resistance to metals has broadened our understanding of metal homeostasis in living organisms. Recent reviews on metal toxicity and resistance mechanisms focused only on the role of transcriptomics, proteomics, metabolomics, and ionomics. This review is a critical analysis of key findings on physiological and genetic processes in plants and microorganisms in responses to soil metal contaminations.


Assuntos
Adaptação Fisiológica/fisiologia , Ecossistema , Metais/toxicidade , Plantas , Microbiologia do Solo , Poluentes do Solo/toxicidade , Animais , Fungos , Metais Pesados , Solo
2.
Orv Hetil ; 160(36): 1407-1416, 2019 Sep.
Artigo em Húngaro | MEDLINE | ID: mdl-31492083

RESUMO

The author briefly summarizes the relationship between oxidative stress and changes in metal ion metabolism in pathological processes. Essential metal ions such as Ca, Mg, Fe, Cu, Zn, Se are essential in the living organisms, their metabolism and intracellular concentration are strictly regulated. Externally or intrinsically, altered metal ion metabolism can lead to metal ion accumulation or metal ion deficiency. Excess amounts of redox-active essential metals such as Fe, Cu, Co, Cr, Ni can induce free radicals under certain circumstances that cause inflammation, cell damage, and cancerous changes, although the molecular mechanism is still unclear in every detail. Changes in the metabolism of non-essential and non-variable valence metal ions also affect redox homeostasis. Despite the fact that each metal can react in a unique way and with different mechanisms, similar processes occur, where both metal deficiency and excessive metal induce oxidative stress. Antioxidant defense system is damaged, free radicals produced alter the redox balance, and redox homeostasis changed induces the production of cytokines and other transcription factors that affect the intracellular signaling pathways and affect the development of various diseases, including metabolic, cardiovascular, neurological diseases and cancer. Orv Hetil. 2019; 160(36): 1407-1416.


Assuntos
Radicais Livres/metabolismo , Homeostase , Metais/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Suscetibilidade a Doenças , Humanos , Metais/metabolismo , Oxirredução
3.
Food Chem ; 299: 125126, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31284243

RESUMO

The health risk assessment of exposure to toxic metals through the consumption food crops is very important. The present study was aimed to investigate the bioaccessibility of toxic metals (including arsenic, lead and cadmium) in rice through an in vitro gastrointestinal digestion model, and assess health risks associated with these metals in raw, cooked and digested rice. Total and bioaccessible concentration of metals were measured by introducing the prepared samples into the inductively coupled plasma-optical emission spectroscopy. Based on the results, the bioaccessible toxic metals in gastric phase were significantly higher than that in both oral and small intestinal phases. The estimated concentrations of these metals in the raw and cooked rice are very far from the actual exposure state. Therefore, to assess the extent of health risks associated with the subjected toxic metals through the rice consumption, the actual exposure value of the metals (bioaccessible value) should be considered.


Assuntos
Arsênico/farmacocinética , Cádmio/farmacocinética , Contaminação de Alimentos/análise , Chumbo/farmacologia , Metais/farmacocinética , Oryza/química , Arsênico/análise , Disponibilidade Biológica , Cádmio/análise , Culinária , Digestão , Humanos , Irã (Geográfico) , Chumbo/toxicidade , Metais/toxicidade , Medição de Risco
4.
Environ Pollut ; 252(Pt B): 1561-1573, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31277025

RESUMO

This review evaluates the three dynamic models (biokinetic model: BK, physiologically based pharmacokinetic model: PBPK, and toxicokinetic-toxicodynamic model: TKTD) in our understanding of the key questions in metal ecotoxicology in aquatic systems, i.e., bioaccumulation, transport and toxicity. All the models rely on the first-order kinetics principle of metal uptake and elimination. The BK model basically treats organisms as a single compartment, and is both physiologically and geochemically based. With a good understanding of each kinetic parameter, bioaccumulation of metals in any aquatic organisms can be studied holistically and mechanistically. Modeling efforts are not merely restrained from the prediction of metal accumulation in the tissues, but instead provide the direction of the key processes that need to be addressed. PBPK is more physiologically based since it mainly addresses the transportation, transformation and distribution of metals in the organisms. It can be treated conceptually as a multi-compartmental kinetic model, whereas the physiology is driving the development of any good PBPK model which is no generic for aquatic animals and contaminants. There are now increasingly applications of the PBPK modeling specifically in metal studies, which reveal many important processes that are impossible to be teased out by direct experimental measurements without adequate modeling. TKTD models further focus on metal toxicity in addition to metal bioaccumulation. The TK part links exposure and bioaccumulation, while the TD part links bioaccumulation and toxic effects. The separation of TK and TD makes it possible to model processes, e.g., toxicity modification by environmental factors, interaction between different metals, at both the toxicokinetic and toxicodynamic levels. TKTD models provide a framework for making full use of metal toxicity data, and thus provide more information for environmental risk assessments. Overall, the three models reviewed here will continue to provide guiding principles in our further studies of metal bioaccumulation and toxicity in aquatic organisms.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Metais/toxicidade , Modelos Teóricos , Oligoelementos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/metabolismo , Transporte Biológico , Ecotoxicologia , Cinética , Metais/metabolismo , Toxicocinética , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo
5.
Bull Environ Contam Toxicol ; 103(3): 391-399, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31338521

RESUMO

The aim of the study was to investigate acute (96-h LC50) toxicity of the complex metal (Zn, Pb, Cd, Cu, Ni and Cr) mixture (MIX) to European perch (Perca fluviatilis) and rainbow trout (Oncorhynchus mykiss), and to examine differences between locomotor and respiratory endpoints based on rapidness and sensitivity of fish responses to short-term (2 h) metal mixture exposure. MIX was prepared taking into consideration the maximum-permissible-concentrations (MPC) set for these metals in EU inland waters (Directive 2008/105/EC). The studied behavioral and respiratory responses of O. mykiss, in contrast to those of P. fluviatilis, were found to be significantly affected by the relationship between exposure duration and treatment. In O. mykiss, gill ventilation frequency (GVF) was found to be the most rapid and sensitive endpoint of all the investigated ones. However, the investigated behavioral and respiratory endpoints of P. fluviatilis showed its behavioral insensitivity to MIX exposure.


Assuntos
Comportamento Animal/efeitos dos fármacos , Brânquias/efeitos dos fármacos , Metais/toxicidade , Oncorhynchus mykiss/fisiologia , Percas/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Respiração
6.
Environ Pollut ; 252(Pt A): 270-280, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31154241

RESUMO

The Rodrigo de Freitas Lagoon (RFL - Rio de Janeiro, RJ, Brazil) is a highly polluted and eutrophic lacustrine system, which has been often used for the practice of aquatic sports, including during the 2016 Summer Olympic Games. This study proposes the evaluation of metal concentrations in surface sediments from the RFL before and after urban interventions performed for the 2016 Olympics, as well as their toxicity to the benthic amphipod Tiburonella viscana and embryos of the sea-urchin Echinometra lucunter. Metal concentrations determined in 2017 were significantly higher than those obtained in 2015 (especially Cu, Cd and Ni), suggesting that the interventions performed to fulfill the requirements of the Olympics increased metal contents in sediments. The sediments from the northern sector of the RFL were muddier, more organically enriched, exhibited higher metal concentrations and were more toxic to T. viscana when compared to the sediments collected in the southern sector. This fact is particularly important since the practice of sports, including during the 2016 Olympics, has been preferably performed in the northern sector. Metal distribution was strongly correlated with organic matter and mud contents. The toxicity to E. lucunter embryos was high for both northern and southern sediments; most of the samples led to 100% lack or abnormal embryonic development. The integration of physical, chemical and ecotoxicological data indicates that the mortality to T. viscana was correlated with metal contents, whereas the toxicity to E. lucunter was apparently related to the release of ammonia from the sediment to water column. Finally, high metal concentrations and the toxicity to aquatic organisms evidence the ecological risks to the biota from RFL.


Assuntos
Anfípodes/efeitos dos fármacos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais/toxicidade , Ouriços-do-Mar/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/análise , Animais , Organismos Aquáticos/efeitos dos fármacos , Brasil , Ecotoxicologia , Metais/análise , Poluentes Químicos da Água/análise
7.
Sci Total Environ ; 685: 332-344, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31176220

RESUMO

The present study assessed the spatial and temporal variations on metal bioaccumulation and biochemical biomarker responses in oysters Crassostrea gasar transplanted to two different sites (S1 and S2) at the Laguna Estuarine System (LES), southern Brazil, over a 45-days period. A multi-biomarker approach was used, including the evaluation of lipid peroxidation (MDA) levels, and antioxidant defense enzymes (CAT, GPx, GR and G6PDH) and phase II biotransformation enzyme (GST) in the gills and digestive gland of oysters in combination with the quantification of Al, Cd, Cu, Pb, Fe, Ni and Zn in both tissues. The exposed oysters bioaccumulated metals, especially Al, Cd and Zn in gills and digestive gland, with most prominent biomarker responses in the gills. Results showed that GPx, GR and G6PDH enzymes offered an increased and coordinated response possibly against metal (Zn, Ni, Cd and Cu) contamination in gills. GST was inversely correlated to Cd levels, being its activity significantly lowered over the 45-d exposure periods at S2. On contrary, in digestive gland GST was slightly positively correlated to Cd, revealing a compensatory mechanism between tissues to protect oysters' cells against oxidative damages, since MDA levels also decreased. CAT also appeared to be involved in the cellular protection against oxidative stress, being increased in gills. However, CAT was negatively correlated to Al levels, which might suggest a possible inhibitory effect of this metal in the gills of C. gasar. Differences between tissues were evident by the Integrative Biomarker Responses version 2 (IBRv2) indexes, which showed different pattern between tissues when studying the sites and exposure periods separately. This study provided evidence for the effectiveness of using a multi-biomarker approach in oyster C. gasar to monitor estuarine metal pollution.


Assuntos
Crassostrea/fisiologia , Monitoramento Ambiental , Metais/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Brasil , Estuários , Brânquias/metabolismo , Inativação Metabólica , Peroxidação de Lipídeos/efeitos dos fármacos , Metais/toxicidade , Oxirredução , Estresse Oxidativo/fisiologia , Poluentes Químicos da Água/toxicidade
8.
Mar Pollut Bull ; 142: 419-427, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31232319

RESUMO

This study investigated the network of polycyclic aromatic hydrocarbon (PAH) degraders in the Yangtze estuarine and coastal areas. Along the estuarine gradients, Proteobacteria and Bacteroidetes were the dominant bacterial phyla, and forty-six potential PAH degraders were identified. The abundance of genes encoding the alpha subunit of the PAH-ring hydroxylating dioxygenases (PAH-RHDα) of gram-negative bacteria ranged from 5.5 × 105 to 5.8 × 107 copies g-1, while that of gram-positive bacteria ranged from 1.3 × 105 to 2.0 × 107 copies g-1. The PAH-degraders could represent up to 0.2% of the total bacterial community and mainly respond to PAHs and Cu concentrations, which indicate anthropogenic activities. Salinity and pH showed negative regulating effects on the PAH-degrading potential and the tolerance of bacteria to pollutants. PAH degraders such as Novosphingobium and Mycobacterium exhibit heavy-metal tolerance and core roles in the network of PAH degraders. These outcomes have important implications for bioremediation.


Assuntos
Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Microbiologia da Água , Poluentes Químicos da Água/metabolismo , Bactérias/genética , Biodegradação Ambiental , Biodiversidade , China , Dioxigenases/genética , Dioxigenases/metabolismo , Estuários , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Concentração de Íons de Hidrogênio , Metais/análise , Metais/toxicidade , Mycobacterium/genética , Mycobacterium/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Proteobactérias/genética , Proteobactérias/metabolismo , Água do Mar/química , Água do Mar/microbiologia , Poluentes Químicos da Água/análise
9.
Environ Sci Pollut Res Int ; 26(24): 24806-24818, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31240654

RESUMO

Migration and transformation of toxic metal (loid) s in tailing sites inevitably lead to ecological disturbances and serious threats to the surroundings. However, the horizontal and vertical distribution of bacterial diversity has not been determined in nonferrous metal (loid) tailing ponds, especially in Guangxi China, where the world's largest and potentially most toxic sources of metal (loid) s are located. Distribution of bacterial communities was stable at horizontal levels. At the surface (0-10 cm), the stability was most attributed to Bacillus and Enterococcus, while bacterial communities at the subsurface (50 cm) were mainly contributed by Nitrospira and Sulfuricella. Variable vertical distribution of bacterial communities has led to the occurrence of specific genera and specific predicted functions (such as transcription regulation factors). Sulfurifustis (a S-oxidizing and inorganic carbon fixing bacteria) genera were specific at the surface, whereas Streptococcus-related genera were found at the surface and subsurface, but were more abundant in the latter depth. Physical-chemical parameters, such as pH, TN, and metal (loid) (As, Cd, Pb, Cu, and Zn) concentrations were the main drivers of bacterial community abundance, diversity, composition, and metabolic functions. These results increase our understanding of the physical-chemical effects on the spatial distribution of bacterial communities and provide useful insight for the bioremediation and site management of nonferrous metal (loid) tailings.


Assuntos
Bactérias/efeitos dos fármacos , Metais/análise , Metais/toxicidade , Mineração , Poluentes Químicos da Água/toxicidade , Biodiversidade , China , Monitoramento Ambiental/métodos , Consórcios Microbianos/efeitos dos fármacos , Consórcios Microbianos/genética , Tanques/microbiologia , RNA Ribossômico 16S , Streptococcus/efeitos dos fármacos , Microbiologia da Água , Poluentes Químicos da Água/análise
10.
Environ Pollut ; 249: 1081-1090, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31146314

RESUMO

In the present study, a screening level site-specific ecological risk assessment (ERA) was conducted on 10 abandoned metal mines in Korea to determine the ecological risk and prioritize the mines requiring further investigation. A cost-saving approach was adopted by combining both the chemical (ChemLoE) and the ecotoxicological (EcotoxLoE) lines of evidence for the evaluation of integrated risk (IR), rather than applying the full spectrum of Triad, including ecological LoE. The risk values for ChemLoE were derived by calculating the toxic pressure based on the total and 0.01 M CaCl2 extractable metal(loid) concentrations. The risk values for EcotoxLoE were based on the mortality and reproduction of the collembolan species Paronychiurus kimi in the mine soils. A response surface model with a central composite design (CCD) was constructed to standardize the effects of soil physicochemical properties (i.e., organic matter content, clay content, and soil pH) on the reproduction of P. kimi. The predicted number of offspring was used as a reference for the calculation of risk value for reproduction. The ChemLoE and EcotoxLoE values ranged from 0.34 to 1.00 and 0.12 to 0.49, respectively, in the surveyed mines. The contribution of the ChemLoE value to the IR was higher than that of the EcotoxLoE value for all mines. Overall, two of the 10 mines were classified as high-risk soils with high IR values (IR > 0.76), but large deviations were also observed between the LoEs in these mines, suggesting the need for further studies to confirm the potential risks. The future investigations of these mines should focus particularly on providing additional evidence to reduce the degree of uncertainty for risk assessment.


Assuntos
Artrópodes/efeitos dos fármacos , Monitoramento Ambiental/métodos , Metais/análise , Mineração , Poluentes do Solo/análise , Solo/química , Animais , Ecotoxicologia , Metais/toxicidade , Reprodução/efeitos dos fármacos , República da Coreia , Medição de Risco , Poluentes do Solo/toxicidade
11.
Chemosphere ; 232: 366-376, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31158631

RESUMO

Metals are present as mixtures in the environment, yet testing such complex mixture poses design and technical challenges. One possible solution is the use of fixed ratios, i.e. rays of increasing metal concentrations. But fixed ratios rays are compromised when soils dosed with metal salts are leached due to metal-soil selectivity rules. Two alternative metal forms, metal oxides and spinel minerals of quinary metal mixtures (Pb, Cu, Co, Ni, Zn), were evaluated for their toxicity to soil microorganisms measured by the activity of ammonia monooxygenases and acid-phosphatases in three soils. Leaching, a required step for salts, had a larger effect on ammonia monooxygenases than metals. Generally, metal salts were the most toxic form, while the spinel minerals were the least toxic form. Two extractants, CaCl2 and DTPA, were evaluated for their ability to link toxicity to metals across all three metal forms. Salt toxicity was closely linked to CaCl2 extractable concentrations but DTPA was the most appropriate for oxides. We strongly recommend combining fixed ratio rays with metal oxides for metal mixture studies, since soil ratios created using oxides were more precise and required less experimental effort compared to salts and spinel minerals. Furthermore, because DTPA and CaCl2 closely tracked the toxicity of more realistic metal forms (i.e. oxides), we recommend that field studies investigating metal mixtures use both DTPA and CaCl2.


Assuntos
Metais/toxicidade , Microbiologia do Solo , Poluentes do Solo/toxicidade , Testes de Toxicidade/métodos , Metais Pesados/análise , Solo , Poluentes do Solo/análise
12.
Environ Sci Pollut Res Int ; 26(22): 22625-22640, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31168715

RESUMO

Endogeic earthworm Metaphire posthuma (Valliant, 1868) is a common biological component of the tropical soil of India and other countries. The species is reported to influence fertility and porosity of soil and bear a high composting potential. Intensive agricultural, industrial, and mining activities increase the amount of toxic metals in soil causing physiological adversity in earthworm and other biotic components in soil. Coelomocytes, the chief immunoeffector cells of earthworm, perform diverse physiological functions under the challenge of toxins and pathogens. The experimental earthworms collected separately from soils with agricultural and tannery activities were subjected to quantitation of prooxidation and antioxidation parameters for estimation of oxidative stress. Total count, cellular aggregation, generation of reactive oxygen species (ROS), superoxide anion, nitric oxide, activities of phenoloxidase, superoxide dismutase, catalase and glutathione-s-transferase, and amount of total protein were estimated in the coelomocytes of M. posthuma as experimental end points of toxicity screening. Concentrations of cadmium, chromium, lead, and mercury were determined in the soil samples to assess the degree of toxic contamination. The increase in the amount of prooxidants and decrease in the activities of antioxidant enzymes indicated the signs of oxidative stress in the coelomocytes of the organism. Aggregation of circulating coelomocytes is considered as an immune response involved in pathogen encapsulation response as reported in many invertebrates. Decrease in coelomocyte aggregation in earthworm collected from contaminated sites suggested a state of inappropriate shift of the innate immune status. Toxin-induced oxidative stress and reductions in cell aggregation response are the signs of immunocompromisation of M. posthuma. Present findings bear a prospect of this experimental species as an indicator of soil pollution.


Assuntos
Coelomomyces/fisiologia , Metais/toxicidade , Oligoquetos/fisiologia , Poluentes do Solo/toxicidade , Agricultura , Animais , Antioxidantes/metabolismo , Cádmio/metabolismo , Catalase/metabolismo , Agregação Celular , Monitoramento Ambiental , Poluição Ambiental , Glutationa Transferase/metabolismo , Índia , Mineração , Oligoquetos/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Solo , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo
13.
Aquat Toxicol ; 212: 128-137, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31103734

RESUMO

We used the WHAM chemical speciation model and the WHAM-FTOX toxicity model to analyse the published results of laboratory toxicity experiments covering 52 different freshwater biological test species and 24 different metals, a total of 2037 determinations of EC50 with accompanying data on solution composition. The key extracted parameter was αM, the parameter in WHAM-FTOX that characterises the toxic potency of a metal on the basis of its estimated metabolically active body burden. For 16 data sets applying to metal-test species pairs with appreciable variations in solution composition, values of EC50 back-calculated from averaged values of αM showed significantly (p < 0.001) less deviation from the measured EC50 values than did the simple average EC50, confirming that the modelling calculations could account for some of the dependence of toxicity on chemical speciation. Data for different exposure times permitted a simple parameterisation of temporal effects, enabling values of αM,max (values at infinite exposure time) to be obtained, and the effects of different exposure times to be factored out for further analysis. Comparison of averaged values of αM,max for different metals showed little difference among major taxa (invertebrates, plants, and vertebrates). For Cd, Cu, Ni and Zn (the four metals with most data) there were significant differences among αM,max values for different species, but within-species variabilities were greater. Reasonably similar species sensitivity distributions of standardised αM,max applied to Cd, Cu, Ni and Zn. The average values, over all species, of αM,max increased in the order Al < lanthanides < Zn ∼ UO2 < Ni ∼ Cu < Pb < Cd < Ag. Considering all the αM,max values, there was a strong dependence (r2 = 0.56, p < 0.001) on Pearson's hardness-softness categories, and a slightly stronger relationship (r2 = 0.59) if ionic radius was included in the statistical model, indicating that softer, larger cations are the most effective toxicants.


Assuntos
Metais/toxicidade , Modelos Químicos , Poluentes Químicos da Água/toxicidade , Animais , Monitoramento Ambiental , Água Doce , Concentração Inibidora 50 , Invertebrados/efeitos dos fármacos , Modelos Estatísticos
14.
Environ Sci Pollut Res Int ; 26(20): 20510-20519, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31102223

RESUMO

Metal-contaminated sediments in lakes is a global concern that poses toxicological risk to aquatic organisms. This study performed bioassays using the submerged macrophyte, Vallisneria natans (Lour.) Hara, exposed to contaminated sediments collected from five locations in Dianchi Lake, Yunnan, China. Among the sediments collected, Igeo showed enrichment of As and Cd in Dianchi Lake sediments. In spite of enriched toxic metals at some locations, laboratory bioassays found no significant difference in leaf biomass or leaf photosynthesis rate between the sites. Root biomass and root activity showed significant differences between locations and were negatively correlated with the concentration of As, Cd, Hg, and Pb in sediment but not related to Cr. The above correlations were strongest for Hg and As, respectively. Accumulation of Cd and Pb to leaves of bioassay plants was observed, but this was not evident for As and Cr. Overall, the results indicate that V. natans can be used as a bioassay organism and measures of root toxicity are sensitive to metal concentrations present in Dianchi Lake sediments. Furthermore, the study species holds promise for use as a biomonitor of Cd and Pb sediment metal content.


Assuntos
Sedimentos Geológicos/análise , Hydrocharitaceae/efeitos dos fármacos , Metais/toxicidade , Poluentes Químicos da Água/toxicidade , Organismos Aquáticos/efeitos dos fármacos , China , Ecotoxicologia/métodos , Biomarcadores Ambientais , Sedimentos Geológicos/química , Hydrocharitaceae/crescimento & desenvolvimento , Hydrocharitaceae/metabolismo , Lagos , Metais/farmacocinética , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Testes de Toxicidade Crônica , Poluentes Químicos da Água/farmacocinética
15.
Ecotoxicol Environ Saf ; 180: 632-645, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31132559

RESUMO

Increasing concentrations of metals in soil have posed a serious threat to the soil environment. The control and evaluation of soil metal hazards demand the establishment of soil ecological criteria, which is mainly based on the obtainment of toxicity thresholds. As the most typical representative of soil-dwelling springtails, Folsomia candida performs numerous essential ecological functions in soil and has been extensively used to investigate metal toxicity effects and thresholds. This review outlined the current state of knowledge on the metal toxicity thresholds to Folsomia candida, including (1) toxicity thresholds of soil metals for the different endpoints, (2) the influence factors of metal toxicity thresholds including the test conditions, the chemical forms of metal, the soil physicochemical properties, aging time and leaching, (3) the bioavailable fractions predicting metal toxicity thresholds, (4) the internal threshold of metals. To conclude, several recommendations for future research are given to obtain the more reliable toxicity thresholds and further supplement the toxicity data of metals to Folsomia candida.


Assuntos
Artrópodes/efeitos dos fármacos , Biomarcadores Ambientais/efeitos dos fármacos , Metaloides/toxicidade , Metais/toxicidade , Poluentes do Solo/toxicidade , Animais , Artrópodes/fisiologia , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Biomarcadores Ambientais/fisiologia , Metaloides/farmacocinética , Metais/farmacocinética , Solo/química , Poluentes do Solo/farmacocinética , Testes de Toxicidade
16.
Environ Pollut ; 251: 264-276, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31082611

RESUMO

The Pearl River Estuary (PRE) is the third largest estuary in China, where estuarine organisms are under metal stress at various biological levels. Based on the metal concentrations measured in oyster Crassostrea hongkongensis, we documented a change in dominance of metal contamination from Cd, Cr, Cu, Ni and Zn to Ag, Cd, Cu and Zn. In general, metal concentrations were higher in upstream stations and displayed a clear up-downstream gradient. Compared to the historical values, we noted the reductions in Cd, Cr and Ni concentrations, and the changing inputs due to evolving industrial activities were responsible for shaping the metal contamination profile in the PRE region. Along with metal concentrations, a suite of biomarkers was analyzed. Among the metals measured in the oyster tissues, Ag, Cd, Cu, Ni and Zn showed the strongest associations with pro-oxidant and oxidative stress responses (superoxide dismutase, lipid peroxidation and lysosomal membrane destabilization) and detoxification responses (glutathione and metallothionein), suggesting that the present metal contamination still exerts significant amount of stress in biota in the PRE. Metal contamination in estuaries in China is still severe compared to other countries, therefore continuous efforts should be taken to monitor the changing metal profiles with necessary control and remediation measures.


Assuntos
Crassostrea/fisiologia , Metais/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , China , Crassostrea/metabolismo , Monitoramento Ambiental , Estuários , Metalotioneína/metabolismo , Metais/análise , Metais Pesados/análise , Estresse Oxidativo , Rios , Alimentos Marinhos , Poluentes Químicos da Água/análise
17.
Environ Sci Pollut Res Int ; 26(17): 17858-17864, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31065978

RESUMO

The phenotypic diversity of ant workers plays a fundamental role in their biology. In this study, we asked if the body size variation of monomorphic workers of the ant Lasius niger (Formicidae) responds adaptively to metal pollution in a post-mining metal-polluted area. Nest samples of workers were collected along a pollution gradient to calculate the within-colony variance in body size (expressed as maximum head width, HW). The results showed that the body size variation of L. niger was unrelated to the pollution index but demonstrated considerable variation between colonies even within the same study site. We suggest that the differences in morphological diversity between the colonies of L. niger could be shaped by colony personality traits, i.e., by colony-specific foraging and/or the feeding efficiency of nursing workers. The study supports previous findings, showing that morphological traits in Lasius ants are weakly related to environmental metal pollution.


Assuntos
Formigas/anatomia & histologia , Metais/análise , Poluentes do Solo/análise , Animais , Formigas/efeitos dos fármacos , Formigas/fisiologia , Tamanho Corporal , Monitoramento Ambiental , Poluentes Ambientais , Poluição Ambiental , Metais/toxicidade , Mineração , Poluentes do Solo/toxicidade
18.
Chemosphere ; 229: 589-601, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31100630

RESUMO

The study aimed to evaluate the physiological mechanisms underlying differences in metals and metalloid uptake and tolerance of two tree species cultivated in mining waste material. Two-year old Acer platanoides L. and Tilia cordata Mill. were cultivated in mining sludge characterized by high pH, salinity and an extremely high concentration of As. Both species were able to develop leaves from leafless seedlings, however, their total biomass was greatly reduced in comparison to control plants, following the severe disturbances in chlorophyll content. Phytoextraction abilities were observed for T. cordata for Ba, Nb, Rb and Se, and phytostabilisation was stated for Pd, Ru, Sc and Sm for both species, Ba and Nd for A. platonoides and Be for T. cordata only. Metal exclusion was observed for the majority of detected elements indicating an intense limitation of metal transport to photosynthetic tissue. A diversified uptake of elements was accompanied by a species-specific pattern of physiological reaction during the cultivation in sludge. Organic ligands (glutatnione and low-molecular-weight organic acids) were suppressed in A. platanoides, and enhanced biosynthesis of phenolic compounds was observed for both species, being more pronounced in T. cordata. Despite its higher accumulation of key metabolites for plant reaction to oxidative stress, such as phenolic acids, flavonoids and organic ligands, T. cordata exhibited relatively lower tolerance to sludge, probably due to the increased uptake and translocation rate of toxic metal/loids to aerial organs and/or restricted accumulation of salicylic acid which is known to play a decisive role in mechanisms of plant tolerance.


Assuntos
Acer/crescimento & desenvolvimento , Mineração , Poluentes do Solo/farmacocinética , Tilia/crescimento & desenvolvimento , Acer/efeitos dos fármacos , Arsênico/análise , Arsênico/farmacocinética , Biodegradação Ambiental , Clorofila/metabolismo , Metais/farmacocinética , Metais/toxicidade , Fotossíntese/efeitos dos fármacos , Fotossíntese/fisiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Especificidade da Espécie , Tilia/efeitos dos fármacos , Árvores/efeitos dos fármacos , Árvores/crescimento & desenvolvimento
19.
Environ Sci Pollut Res Int ; 26(17): 16939-16951, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31028621

RESUMO

Mining activities are responsible for the elevated input levels of suspended sediment and hazardous metals into the riverine ecosystem. These have been shown to threaten the riverine fish populations and can even lead to localized population extinction. To date, research on the effects of mining activities on fish has been focused within metal contamination and bioaccumulation and its threat to human consumption, neglecting the effects of suspended sediment. This paper reviews the effects of suspended sediment and metal pollution on riverine ecosystem and fish population by examining the possibilities of genetic changes and population extinction. In addition, possible assessments and studies of the riverine fish population are discussed to cope with the risks from mining activities and fish population declines.


Assuntos
Monitoramento Ambiental/métodos , Peixes/crescimento & desenvolvimento , Sedimentos Geológicos/química , Metais/toxicidade , Mineração , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Humanos , Metais/análise , Dinâmica Populacional , Poluentes Químicos da Água/análise
20.
Environ Toxicol Pharmacol ; 69: 120-128, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31026736

RESUMO

Few studies have compared the biological effects of PM2.5 from coal combustion, gasoline exhaust and urban ambient air, and the roles of polycyclic aromatic hydrocarbons (PAHs) and metals playing in the process remain unclear. In this study, PM2.5 samples from coal combustion, gasoline exhaust and urban ambient air were analyzed for 16 PAHs and 23 metals. Cytotoxic and inflammatory effects of different PM2.5 were evaluated on differentiated THP-1 and A549 cells, respectively. We found that the coal combustion PM2.5 samples induced stronger cytotoxic and inflammatory effects (p < 0.05). Pearson's correlation and principal component analysis showed that the PAHs containing four or more benzenoid rings and specific metals of cadmium, thallium, zinc and lead were positively related to the biological effects. Our results suggested that coal combustion PM2.5 might be a more serious health hazard. Specific PAHs and metals might be account for the PM2.5 induced biological effects.


Assuntos
Poluentes Atmosféricos/toxicidade , Carvão Mineral , Gasolina , Metais/toxicidade , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Emissões de Veículos/toxicidade , Células A549 , Poluentes Atmosféricos/análise , Sobrevivência Celular/efeitos dos fármacos , Cidades , Humanos , Metais/análise , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Células THP-1 , Emissões de Veículos/análise
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