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1.
Chemosphere ; 244: 125543, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050340

RESUMO

Environmentally friendly and cost-effective techniques are required to reclaim land degraded during mining activities. Bioaccumulation of heavy metals (HMs) in vegetables grown on contaminated soils can increase human health risks. The potential effects of hardwood biochar (HWB) was assessed for chromium (Cr), zinc (Zn), copper (Cu), manganese (Mn) and lead (Pb) bioavailability in mine-contaminated soils and their subsequently bioaccumulation in crops and associated health risk. HWB was applied to chromium-manganese mine contaminated soils at the rate of 3% to investigate the efficiency of HWB for the second crop in crop rotation technique. Cilantro (Coriandrum sativum) and spinach (Spinaccia oleracea) were grown as second crop in the same pots which were already used for rice cultivation as first crop (without adding further amendments). Application of HWB decreased the concentrations of Cr, Zn, Cu, Mn, and Pb in cilantro by 25.5%, 37.1%, 42.5%, 34.3%, and 36.2%, respectively as compared to control. In spinach, the reduction in concentrations of Cr was 75.0%, Zn 24.1%, Cu 70.1%, Mn 78.0%, and Pb 50.5% as compared to control. HWB significantly (P < 0.01) reduced the HMs uptake in spinach cultivated in the amended soils as compared to the spinach in control. Bioaccumulation factor results also indicate that HWB decreased the bioaccumulation of selected HMs in cilantro and spinach, thus reducing health risks. Results of the study clearly demonstrate that the use of HWB can significantly reduce HMs in vegetables, associated health risk and improve food quality, therefore can be used as soil amendment for reclamation of mine-degraded soils.


Assuntos
Carvão Vegetal , Coriandrum/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Spinacia oleracea/metabolismo , Agricultura/estatística & dados numéricos , Disponibilidade Biológica , Cobre/metabolismo , Produtos Agrícolas/metabolismo , Exposição Dietética/estatística & dados numéricos , Humanos , Manganês/metabolismo , Metais Pesados/análise , Mineração , Oryza/metabolismo , Solo , Poluentes do Solo/análise , Verduras/metabolismo , Zinco/análise
2.
J Agric Food Chem ; 68(7): 1958-1965, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32003983

RESUMO

Heavy metal stress is a major growth- and yield-limiting factor for plants. Heavy metals include essential metals (copper, iron, zinc, and manganese) and non-essential metals (cadmium, mercury, aluminum, arsenic, and lead). Plants use complex mechanisms of gene regulation under heavy metal stress. MicroRNAs are 21-nucleotide non-coding small RNAs as important modulators of gene expression post-transcriptionally. Recently, high-throughput sequencing has led to the identification of an increasing number of heavy-metal-responsive microRNAs in plants. Metal-regulated microRNAs and their target genes are part of a complex regulatory network that controls various biological processes, including heavy metal uptake and transport, protein folding and assembly, metal chelation, scavenging of reactive oxygen species, hormone signaling, and microRNA biogenesis. In this review, we summarize the recent molecular studies that identify heavy-metal-regulated microRNAs and their roles in the regulation of target genes as part of the microRNA-associated regulatory network in response to heavy metal stress in plants.


Assuntos
Metais Pesados/metabolismo , MicroRNAs/metabolismo , Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Homeostase , MicroRNAs/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/genética
3.
Ecotoxicol Environ Saf ; 190: 110089, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31896472

RESUMO

The use of algae to adsorb heavy metals is an efficient and environmentally friendly treatment for contaminated water and has attracted widespread research attention. In this study, a meta-analysis of the heavy metal adsorption capacity of algae from five different phyla and the factors influencing these capacities was conducted. Phaeophyta was found to have a high heavy metal adsorption capacity, whereas Bacillariophyta had a relatively low adsorption capacity; Chlorophyta, Rhodophyta, and Cyanophyta had moderate adsorption capacities. Non-living algae were more effective in practical applications than living algae were. Algal biomass had a relatively high adsorption efficiency of 1-10 g/L, which did not increase significantly when algal concentration increased. The algal adsorption efficiency for initial heavy metal concentrations of 10-100 mg/L was higher than for concentrations of greater than 100 mg/L. The results further show that algal adsorption of heavy metals reached a maximum capacity of 80-90% within 20 min. Heavy metal adsorption by algae was not temperature-dependent, and it was more effective in moderately to weakly acidic environments (pH = 4-7.5). Considering these aspects for practical applications, algae from some phyla can effectively be used for heavy metal biosorption in contaminated water.


Assuntos
Clorófitas/metabolismo , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Adsorção , Biomassa , Concentração de Íons de Hidrogênio , Feófitas , Rodófitas , Temperatura Ambiente
4.
Environ Pollut ; 256: 113389, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31685327

RESUMO

The boreoatlantic gonate squid (Gonatus fabricii) represents important prey for top predators-such as marine mammals, seabirds and fish-and is also an efficient predator of crustaceans and fish. Gonatus fabricii is the most abundant cephalopod in the northern Atlantic and Arctic Ocean but the trace element accumulation of this ecologically important species is unknown. In this study, trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, and Zn) were analysed from the mantle muscle and the digestive gland tissue of juveniles, adult females, and adult males that were captured south of Disko Island off West-Greenland. To assess the feeding habitat and trophic position of this species, stable isotopes of carbon (δ13C) and nitrogen (δ15N) were measured in their muscle tissue. Mercury concentrations were positively correlated with size (mantle length) and trophic position. The Hg/Se ratio was assessed because Se has been suggested to play a protective role against Hg toxicity and showed a molar surplus of Se relative to Hg. Cadmium concentrations in the digestive gland were negatively correlated with size and trophic position (δ15N), which suggested a dietary shift from Cd-rich crustaceans towards Cd-poor fish during ontogeny. This study provides trace element concentration data for G. fabricii from Greenlandic waters, which represents baseline data for a northern cephalopod species. Within West-Greenland waters, G. fabricii appears to be an important vector for the transfer of Cd in the Arctic pelagic food web.


Assuntos
Bioacumulação , Decapodiformes/metabolismo , Monitoramento Ambiental/métodos , Metais Pesados/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Regiões Árticas , Oceano Atlântico , Clima Frio , Ecossistema , Feminino , Cadeia Alimentar , Masculino , Metais Pesados/metabolismo , Alimentos Marinhos/análise , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo
5.
Environ Pollut ; 256: 113378, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31662243

RESUMO

Heavy metal contamination is a serious environmental problem commonly monitored in various organisms. Small wild rodents are ideal biological monitors to show the extent of environmental pollution. The aim of this study was to evaluate the adverse effects of marble and stone quarries on the Levant vole, Microtus guentheri, inhabiting some polluted sites. In this context, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to analyze distribution of thirteen heavy metals (Fe, Al, Zn, Cu, Cr, Mn, Ni, B, Pb, As, Co, Cd, and Hg) in the organs (skins, bones, muscles, livers and kidneys) of the biological specimens, and the comet assay revealed DNA damage in blood lymphocytes for the first time. This study was conducted at close to the marble and stone quarries at Korkuteli, Antalya-Turkey during spring, summer, autumn (2017) and winter (2018) seasons. In spring and summer, genetic damage in blood lymphocytes from all polluted sites (sites 1-5) was significantly higher than that of controls, while in autumn it was higher in samples from three sites (sites 3-5). In terms of heavy metal distribution in organs, we found depositions of Fe, Al, Zn, Ni, Mn, Cr, Co, As and Pb primarily in the skin with its derivatives, Cu and Cd deposits in the kidney, Cu, Cd and B deposits in the liver, and As and Pb depositions in the bones. The study shows that certain organs (especially skin with its derivatives) and blood lymphocytes of Levant vole can be used as ideal indicators of heavy metal pollution. Our results suggest that the Korkuteli area could already be under the threat of heavy metal pollution.


Assuntos
Arvicolinae/metabolismo , Bioacumulação , Dano ao DNA , Monitoramento Ambiental/métodos , Poluentes Ambientais/toxicidade , Metais Pesados/toxicidade , Mineração , Animais , Arvicolinae/genética , Poluentes Ambientais/metabolismo , Metais Pesados/metabolismo , Estações do Ano , Turquia
6.
Environ Pollut ; 256: 113388, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31662258

RESUMO

The most significant risk factor for organisms living in an environment contaminated by heavy metals is the metal bioavailability. Therefore, an efficient ecotoxicological approach to metal contamination is the measure of bioaccumulation level in target organisms. In this work, we characterized the heavy metal bioaccumulation in honey bees, Apis mellifera ligustica, collected at 35 sites from Umbria (Central Italy). The comparison of our data with selected Italian investigations revealed metal bioaccumulation in honey bee matrix of the same order of magnitude, with Cd showing a higher variability. To generalize the results, we developed a Honeybee Contamination Index (HCI) based on metal bioaccumulation in honey bees. An application of the HCI to the present dataset revealed cases of low (sixteen sites), intermediate (eighteen sites), and high (one site) metal contaminations. The comparison of HCI values from the Umbrian dataset with values calculated for other Italian and European metadata showed that most of the Umbrian sites fell in the portion of low and intermediate contamination conditions. HCI represented a reliable tool that provided a piece of concise information on metal contamination in terrestrial environments. Parallel to this effort, we have determined, the metal concentrations in the airborne particulate matter (PM10) at three regional background-monitoring stations in Umbria. These stations are representative of the average air quality of the areas of the investigated apiaries. A comparative analysis of metal enrichment factors in PM10, and honey bees suggested that the contamination in the bees was related to the PM10 values only to a minor extent. On the other side, a clear enrichment of metals such as Cd, Mn, Zn, and Cu in the honey bees appeared to depend on very local conditions and was probably related to the use of pesticides and fertilizers, and the resuspension of the locally contaminated soils and agriculture residues.


Assuntos
Abelhas/metabolismo , Bioacumulação , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Metais Pesados/análise , Animais , Poluentes Ambientais/metabolismo , Itália , Metais Pesados/metabolismo , Praguicidas/análise , Praguicidas/metabolismo
7.
Environ Pollut ; 256: 113387, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677879

RESUMO

Constructed wetland effectiveness is often assessed by measuring reductions of contaminant concentrations in influent versus departing effluent, but this can be complicated by fluctuations in contaminant content/chemistry and hydrology. We assessed effectiveness of a constructed wetland at protecting downstream biota from accumulating elevated metal concentrations-particularly copper and zinc in effluents from a nuclear materials processing facility. Contaminants distributed throughout a constructed wetland system and two reference wetlands were assessed using six dragonfly nymph genera (Anax, Erythemis, Libellula, Pachydiplax, Tramea, and Plathemis) as biomonitors. Additionally, the crayfish, Cambarus latimanus, were analyzed from the receiving and two reference streams. Concentrations of Cu, Zn, Pb, Mn, Cr, Cd, and Al were evaluated in 597 dragonfly nymph and 149 crayfish whole-body composite samples. Dragonfly genera varied substantially in metal accumulation and the ability to identify elevated metal levels throughout components of the constructed wetland. Genera more closely associated with bottom sediments tended to accumulate higher levels of metals with Libellula, Pachydiplax, and Erythemis often accumulating highest concentrations and differing most among sites. This, combined with their abundance and broad distributions make the latter two species suitable candidates as biomonitors for constructed wetlands. As expected, dragonfly nymphs accumulated higher metal concentrations in the constructed wetland than reference sites. However, dragonfly nymphs often accumulated as high of metal concentrations downstream as upstream of the water treatment cells. Moreover, crayfish from the receiving stream near the constructed wetland accumulated substantially higher Cu concentrations than from downstream locations or reference streams. Despite reducing metal concentrations at base flow and maintaining regulatory compliance, metal fluxes from the wetland were sufficient to increase accumulation in downstream biota. Future work should evaluate the causes of downstream accumulation as the next step necessary to develop plans to improve the metal sequestering efficiency of the wetland under variable flow regimes.


Assuntos
Astacoidea/metabolismo , Monitoramento Ambiental/métodos , Metais Pesados/análise , Ninfa/metabolismo , Odonatos/metabolismo , Poluentes Químicos da Água/análise , Áreas Alagadas , Animais , Bioacumulação , Biodegradação Ambiental , Sedimentos Geológicos/química , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo
8.
Bull Environ Contam Toxicol ; 104(1): 90-95, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31728558

RESUMO

We conducted exposure assessment using toenails from 20 fishermen living in Bodo City, a community of the Niger delta region in Nigeria. This community has been affected by over 4000 oil spills and environmental disasters. Fishing is the primary source of food and income for individuals in this community. Previous research in Bodo City found elevated metal levels in fish. Toenails were used as a biomarker to investigate the feasibility for use in risk assessment studies in developing countries. The toenails collected had significantly higher manganese levels (median 5.8 µg/g) and lead levels (median 0.98 µg/g) than those reported in more developed countries, comparable levels to those from other low-middle incomes countries. These exposure levels are likely a direct result of exposures from the environmental disasters the community has experienced and would be related to increased risks for many diseases previously associated with heavy metal exposures.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Metais Pesados/metabolismo , Unhas/química , Poluentes Químicos da Água/metabolismo , Biomarcadores , Monitoramento Ambiental , Contaminação de Alimentos , Humanos , Chumbo , Manganês/análise , Metais Pesados/análise , Nigéria , Poluição por Petróleo , Alimentos Marinhos , Poluentes Químicos da Água/análise
9.
J Photochem Photobiol B ; 202: 111638, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31733613

RESUMO

The present study investigates the phycoremediation potentials of two microalgal consortia (MAC1 and MAC2) for treating sewage water and producing biomass with high lipid, protein and chlorophyll contents. During the study, the microalgal strains were tested for lipid enhancement, biomass production and contaminant removal from wastewater. The microalgal consortia showed prolific growth in wastewater with 75% dilution and accumulated higher lipid content of 31.33% dry cell weight in MAC1. The maximum biomass (50% diluted wastewater) for both the consortia was 1.53 and 1.04 gL-1. Total chlorophyll (19.17-25.17 µg mL-1) and protein contents (0.12-0.16 mg mL-1) for both the consortia were found to be maximum in 75 WW. MAC1 was capable of removing 86.27% of total organic carbon and 87.6% of chemical oxygen demand. Approximately, 94% of nitrate and phosphate contents were removed from the initial contents of wastewater. Heavy metal removal efficiency was also found to be better and showed 85.06% Cu, 75.2% Cr, 98.2% Pb, and 99.6% Cd removal by the algal consortia. Pyrolytic decomposition of algal consortia was observed using thermogravimetric analysis. The stepwise decomposition of algae indicated distinct losses of functional groups. The gas chromatography-mass spectrometric analysis revealed the majority of saturated fatty acids followed by monounsaturated and polyunsaturated fatty acids. Thus, the present study proved that both the consortia show tremendous potential for the treatment of domestic wastewaters with successive lipid enhancement for biodiesel production.


Assuntos
Biocombustíveis/análise , Ácidos Graxos/metabolismo , Microalgas/crescimento & desenvolvimento , Eliminação de Resíduos Líquidos/métodos , Proteínas de Algas/metabolismo , Biomassa , Clorofila/análise , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas , Metais Pesados/química , Metais Pesados/metabolismo , Microalgas/metabolismo
10.
Bull Environ Contam Toxicol ; 104(1): 134-143, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31748864

RESUMO

This study was carried out to develop mathematical regression equations for predicting the uptake of ten heavy metals (HMs) (cadmium, Cd; cobalt, Co; chromium, Cr; copper, Cu; iron, Fe; manganese, Mn; molybdenum, Mo; nickel, Ni; lead, Pb; zinc, Zn) by a vegetable species (Eruca sativa Mill.) in the Abha region (Saudi Arabia) based on the concentration of these HMs in soils amended with sewage sludge, organic matter (OM) content and soil pH. The resultant regression equations indicated that the three soil factors were significant predictors for the uptake of the ten HMs in the plant tissues. By applying a t test, we found that there are no significant differences between the actual and predicted values of the ten HMs in the E. sativa roots and leaves (P > 0.05), which reflects the goodness of fit of these equations for predicting the uptake of these HMs. Such types of equations may be helpful for evaluating the risk of cultivation of E. sativa plants in soils amended with sewage sludge.


Assuntos
Brassicaceae/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Brassicaceae/química , Cádmio/análise , Cobre/análise , Manganês/análise , Metais Pesados/análise , Níquel/análise , Folhas de Planta/química , Raízes de Plantas/química , Plantas , Arábia Saudita , Esgotos/química , Solo/química , Poluentes do Solo/análise , Verduras , Zinco/análise
11.
Ecotoxicol Environ Saf ; 190: 110084, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31869713

RESUMO

Metals in acid mine drainages (AMD) have posed a great threat to environment, and in situ economic environment-friendly remediation technologies need to be developed. Moreover, the effects of acidophiles on biosorption and migrating behaviors of metals in AMD have not been previously reported. In this study, the extremely thermoacidophilic Archaea, Acidianus manzaensis YN25 (A. manzaensis YN25) was used as a bio-adsorbent to adsorb metals (Cu2+, Ni2+, Cd2+ and Zn2+) from acidic solutions which were taken to imitate AMD. The values of their maximum biosorption capacities at both high (1 mM) and low (0.1 mM) metal concentrations followed the order: Cu2+ > Ni2+ > Cd2+ > Zn2+. With the elevations of temperature and pH value, the adsorption amounts of metals increased. The results also indicated that A. manzaensis YN25 had the highest adsorption affinity to Cu2+ in coexisting system of quaternary metals. Acid-base titration data revealed that carboxyl and phosphoryl groups provided adsorption sites for metals via deprotonation. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) further corroborated that amino played an important role in the biosorption process. The fitted Langmuir model illustrated monolayer adsorption occurring on cell surface. The possible adsorption mechanism of A. manzaensis YN25 mainly involved in electrostatic attraction and complexes formation. This study gives a profound insight into the biosorption behavior of heavy metals in acidic solution by thermoacidophilic Archaea and provides a probable novel strategy for in situ remediation of heavy metals pollution in AMD.


Assuntos
Acidianus/fisiologia , Biodegradação Ambiental , Mineração , Poluentes Químicos da Água/metabolismo , Adsorção , Archaea/metabolismo , Íons Pesados , Concentração de Íons de Hidrogênio , Íons , Metais Pesados/análise , Metais Pesados/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
12.
Ecotoxicol Environ Saf ; 187: 109828, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31639644

RESUMO

Different forms of aluminum (Al) in soil can be toxic to plants and the bacterial community. In our previous study, the distribution and toxicity to plants of soil Al species and soil labile Al fractions were examined. However, the toxicity of different forms of Al on the bacterial community has not been completely studied. In this study, five soil samples (pH: 4.92, 6.17, 6.62, 6.70, 8.51) were collected from Lichuan, China. Tall fescue was planted in rhizosphere boxes with those soils for 120 days. The toxicity of soil Al species and soil labile Al fractions on the bacterial community of near-rhizosphere (NR) soils and far-rhizosphere (FR) soils were analyzed. The effect of different forms of Al on bacterial community between NR and FR soils was small, but the difference was obvious according to the different spatial distribution of samples. An individual bacterial community has eosinophilia, and most bacterial communities are tolerant of heavy metals (e.g., Cu, Zn, Cd). The toxicity of exchangeable Al has a strong effect on the bacterial community. Meanwhile, the toxicity of Al3+ to the bacterial community is strong. In this study, the key finding was that the toxicity of the Al-F- complex toward the bacterial community and plants was different. AlF2+, AlF2+, AlF3, and AlF4- are toxic for the bacterial community, and the correlation decreases with the addition of F-. This finding is of considerable significance to the treatment of acid-contaminated soil and the study of the tolerance mechanism of plants toward Al.


Assuntos
Alumínio/toxicidade , Festuca/microbiologia , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Poluentes do Solo/toxicidade , Alumínio/química , Biodegradação Ambiental , Festuca/metabolismo , Concentração de Íons de Hidrogênio , Metais Pesados/metabolismo , Rizosfera , Solo/química , Poluentes do Solo/química
13.
Ecotoxicol Environ Saf ; 187: 109830, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31648074

RESUMO

A second intracellular copper/zinc superoxide dismutase (icCuZnSOD2) and manganese SOD (MnSOD) were cloned and characterized in Oxya chinensis. The open reading frame (ORF) of OcicCuZnSOD2 and OcMnSOD are 462 and 672 bp encoding 153 and 223 amino acids, respectively. OcicCuZnSOD2 contains two signature sequences, one potential N-glycosylation site, and seven copper/zinc binding sites. OcMnSOD includes a mitochondria targeting sequence of 7 amino acids at N-terminal, one signature sequence, two N-glycosylation sites, and four manganese binding sites. The secondary structure and homology model of OcicCuZnSOD2 include nine ß sheets, two Greek-key motifs, and one electrostatic loop. OcMnSOD contains nine α-helices and three ß-sheets. Phylogenetic analysis shows that OcMnSOD is evolutionarily conserved while OcicCuZnSOD2 may be gene duplication and is paralogous to OcicCuZnSOD1. OcMnSOD expressed widely in all tissues and developmental stages. OcicCuZnSOD2 showed testis-specific expression and expressed highest in the 5th-instar nymph and the adult. The optimum temperatures and pH values of the recombinant OcicCuZnSOD2 and OcMnSOD were 40 °C and 8.0. They were stable at 25-55 °C and at pH 5.0-12.0 and pH 6.0-12.0, respectively. The activity and mRNA expression of each OcSOD were assayed after chlorpyrifos treatments. Total SOD and CuZnSOD activities first increased then declined under chlorpyrifos stress. Chlorpyrifos induced the mRNA expression and activity of OcMnSOD as a dose-dependent manner and inhibited OcicCuZnSOD2 transcription. The role of each OcSOD gene in chlorpyrifos stress was investigated using RNAi and disc diffusion assay with Escherichia coli overexpressing OcSOD proteins. Silencing of OcMnSOD significantly increased ROS content in chlorpyrifos-exposed grasshoppers. Disc diffusion assay showed that the plates with E. coli overexpressing OcMnSOD had the smaller inhibition zones around the chlorpyrifos-soaked filter discs. These results implied that OcMnSOD played a significant role in defense chlorpyrifos-induced oxidative stress.


Assuntos
Clorpirifos/metabolismo , Gafanhotos/enzimologia , Proteínas de Insetos/fisiologia , Metais Pesados/metabolismo , Superóxido Dismutase/fisiologia , Animais , Cobre/metabolismo , Gafanhotos/classificação , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Manganês/metabolismo , Filogenia , Superóxido Dismutase/química , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Zinco/metabolismo
14.
J Environ Sci (China) ; 86: 87-96, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31787193

RESUMO

Sedum alfredii Hance is a cadmium (Cd)/zinc (Zn) hyperaccumulator native to China. However, its relatively low biomass restricted the large-scale application for heavy metal contamination remediation. The chromosome set doubling of S. alfredii in vitro was achieved by 0.1%-0.2% (W/V) colchicine treatment. The plant DNA ploidy was analyzed by flow cytometry and chromosome set doubling plants (CSD) were identified based on the obvious different sharp peak. A tissue culture experiment with different Cd treated levels and a field trial with natural polluted mined soil were conducted to study the effects of chromosome doubling on plant biomass and Cd accumulation in shoots. The results suggested that S. alfredii is a mixoploid. Compared with the wild type plants (WT), CSD exhibited typical "gigas" characteristics in morphology including stem thickness, root hair production, number of leaves and size of stoma guard cell. Fresh weight and dry weight of CSD were increased to 1.62-2.03-fold and 2.26-3.25-fold of WT. And Cd content of CSD showed a 17.49%-42.82% increase and 59% increase under tissue culture and field condition, accordingly. In addition, the TF and in BCF of CSD were 2.37- and 1.59-fold of WT, respectively. These results proved that it is feasible to promote phytoextraction efficiency of S. alfredii in Cd contaminated soils through chromosomal engineering, which provides a novel approach for hyperaccumulator application in phytoremediation.


Assuntos
Biodegradação Ambiental , Cromossomos , Metais Pesados/metabolismo , Sedum/genética , Poluentes do Solo/metabolismo , China , Sedum/metabolismo
15.
Environ Monit Assess ; 192(1): 31, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823064

RESUMO

A three-dimensional contaminant transport model of heavy metal (copper) was coupled with the hydrodynamics and suspended sediment transport module to simulate the transport and distribution of heavy metal (copper) of the Danshui River estuarine system in northern Taiwan. The coupled model was validated with observational data including the water level, tidal current, salinity, suspended sediment concentration, and copper concentration. The model simulation results quantitatively reproduce the measurements. Furthermore, the validated model was employed to explore the influences of the freshwater discharge and suspended sediment on the distribution of copper concentrations in the tidal estuarine system. The results demonstrate that a high freshwater discharge results in a decreasing copper concentration, while a low freshwater discharge raises the copper concentration along the estuarine system. If the suspended sediment transport module was excluded in the model simulations, the predicted copper concentration underestimated the measured data. The distribution of copper concentrations without the suspended sediment transport module was lower than that with the suspended sediment transport module. The simulated results indicate that the freshwater discharge and suspended sediment play crucial roles in affecting the distribution of copper concentrations in the tidal estuarine system.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Águas Salinas/química , Poluentes Químicos da Água/análise , Simulação por Computador , Cobre/análise , Cobre/metabolismo , Água Doce/química , Sedimentos Geológicos/química , Hidrodinâmica , Metais Pesados/metabolismo , Modelos Teóricos , Taiwan , Poluentes Químicos da Água/metabolismo
16.
Environ Sci Pollut Res Int ; 26(34): 35275-35280, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31745772

RESUMO

The objective of this study is to investigate the contributions of Mikania micrantha (chinese creeper) to remediate heavy metal pollutants present in an e-waste-contaminated soil. Different proportions of e-waste soil (0%, 25%, 50%, 75%, and 100% w/w) planted with Cynodon dactylon together with the test species were prepared for testing relative seed germination (RSG), relative root growth (RRG), and germination index (GI) tests. A significant higher value of GI (77.8%) was found in M. micrantha than that of the other species when planting in 100% e-waste-contaminated soil. A significant correlation (< 0.05) was found between heavy metal concentration and germination assays in M. micrantha. A significant decrease in heavy metal concentration of the polluted soil after the experiment indicated that biomolecule development studies to determine the aggregate benefit of M. micrantha for phytoremediation remain to be studied in future.


Assuntos
Resíduo Eletrônico , Metais Pesados/metabolismo , Mikania/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Germinação , Metais Pesados/análise , Solo , Poluentes do Solo/análise
17.
Environ Sci Pollut Res Int ; 26(36): 36942-36951, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31745797

RESUMO

Canadian goldenrod (Solidago canadensis L.) is a plant that grows in a variety of environmental conditions. It shows high capability to spread in various habitats, including fallow lands and brownfield land. The research aimed at analyzing the content of Pb and Zn in the underground (roots, rhizomes) and aboveground parts (stems, leaves, inflorences) of Solidago canadensis (SC) originating from two locations that are clearly different in terms of metal content in soil. Statistically significant differences were determined in the content of Pb and Zn in soil and particular morphological parts of the plant, depending on the sampling location. It has been shown that in the conditions of increased (compared with natural) Pb and Zn content in the soil, SC may serve as a bioaccumulator of these metals. It was determined that SC can be used as a phytostabilizer of Pb and Zn in soils heavily contaminated with these elements. The content of Zn in the aboveground parts of SC indicates that this plant can also be used for phytoextraction of soils contaminated with this metal.


Assuntos
Biodegradação Ambiental , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Solidago/metabolismo , Canadá , Chumbo/metabolismo , Metais Pesados/análise , Folhas de Planta/química , Raízes de Plantas/química , Solo , Poluentes do Solo/análise , Zinco/metabolismo
18.
Bull Environ Contam Toxicol ; 103(6): 822-827, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31583423

RESUMO

The present study shows the human health risk of Cd, Cu, Hg and Zn by consumption of clams Megapitaria squalida from Northwest Mexico, collected in 2013. The mean concentration for each metal in the soft tissue was: Zn > Cu > Cd > Hg; and mean values of 68.89 ± 37.59-30.36 ± 27.19, 8.77 ± 1.35-6.80 ± 0.36, 4.47 ± 0.21-3.18 ± 0.63 and 0.99 ± 0.81-0.52 ± 0.16 µg/g, respectively. Clam age was significantly negatively correlated (p < 0.05) with soft tissue Zn concentrations. For all metals there is a low level of human health risk associated with the consumption of M. squalida, but it is necessary to determine the specific characteristics of the human population of the study site.


Assuntos
Envelhecimento/metabolismo , Bivalves/química , Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Bioacumulação , Bivalves/crescimento & desenvolvimento , Humanos , Metais Pesados/metabolismo , México , Medição de Risco , Poluentes Químicos da Água/metabolismo
19.
Mar Pollut Bull ; 145: 436-447, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590808

RESUMO

Despite the beneficial aspect of aquatic food's consumption, bioaccumulation of toxic metals in fish can enhance the health risk for the consumers. Heavy metals were measured from editable tissues of some commercial fish species like Latis calcarifer, Silonia silondia, Clupisoma garua, Planiliza subviridis, Otolithoides pama, Tenulosa ilisa, Rhinomugil corsula, and Aila coila in the Meghna river estuary in Noakhali district. Heavy metals such as As, Pb, Cd, Cu, and Cr were detected by ICP-MS, which were significantly different (p ≤ 0.01), and the hierarchy of all mean concentrations were: Cu (5.14 mg/kg) > Pb (3.79 mg/kg) > As (1.08 mg/kg) > Cr (0.78 mg/kg) > Cd (0.12 mg/kg). The mean concentration of Cu (6.62 mg/kg) imparted to the maximum level in L. calcarifer, which slightly exceeded the Bangladesh food safety guideline. The mean BAFs of the contaminants were found as: Pb (1042.29) > Cr (1036.47) > As (934.84) > Cd (832.77) > Cu (772). Further, L. calcarifer, S. silondia, C. garua, and P. subviridis showed the bioaccumulative status. To assess the health risk effects, estimated daily intake (EDI), target hazard quotient (THQ) and carcinogenic risk (CR) were conducted. THQs for both adult and children consumers were <1, indicating that, consumers would not experience the non-carcinogenic health effects. Although children were more susceptible than adults, CR for all the consumers was found in the acceptable range (10-6 to 10-4).


Assuntos
Peixes/metabolismo , Carne/análise , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , Adulto , Idoso , Animais , Bangladesh , Qualidade de Produtos para o Consumidor , Estuários , Feminino , Contaminação de Alimentos/análise , Humanos , Masculino , Metais Pesados/metabolismo , Pessoa de Meia-Idade , Medição de Risco , Poluentes Químicos da Água/metabolismo , Adulto Jovem
20.
Mar Pollut Bull ; 145: 56-66, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590824

RESUMO

The concentration of nine trace elements were analyzed in the different tissue organs of commonly available crabs (Portunus sanguinolentus, Portunus pelagicus and Scylla serrate) and bivalve (Polymesoda erosa) species collected from the Miri coast, Borneo in order to evaluate the potential health risk by consumption of these aquatic organisms. Among the analyzed organs, metal accumulation was higher in the gill tissues. The essential (Cu and Zn) and non-essential (Pb and Cd) elements showed the highest (i.e. Zn) and lowest concentrations (i.e. Cd) in their tissue organs, respectively. The estimated daily intake and hazard indices of all metals in the muscle indicate that the measured values were below the provisional tolerable daily intake suggested by the joint FAO/WHO Expert Committee on Food Additives. Compared to Malaysian and international seafood guideline values the results obtained from the present study are lower than the permissible limits and safe for consumption.


Assuntos
Bivalves/metabolismo , Braquiúros/metabolismo , Metais Pesados/metabolismo , Frutos do Mar/análise , Oligoelementos/metabolismo , Animais , Bornéu , Malásia , Medição de Risco , Poluentes Químicos da Água/metabolismo
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