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1.
Chemosphere ; 262: 127808, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32755693

RESUMO

In terms of investigating the authentic plant biomonitoring and phytoextraction potentials, the samples of soils and shoots of the sun spurge (SS) and common nettle (CN), were collected near several polluted water bodies in the close vicinity of the copper mining/metallurgical complex in Bor (Serbia) and characterized with regard to the content of heavy metal(oid)s: As, Cd, Pb, Cu, and Zn. The methods applied in this work such as inductively coupled plasma-mass spectrometry, one-way analysis of variance, Pearson's correlation study, hierarchical cluster analysis, and the calculation of bioaccumulation rates (expressed through the so called mobility ratios, MRs), provided very informative data on the potentials of both investigated pioneer species. The most important findings were: 1) In most cases, SS was more effective in metal extraction/translocation/bioaccumulation than CN, and especially with regard to Cu; in this particular case, extremely high concentrations were recorded and also, some significant MRs were calculated, which may be a signal of its promising potential for Cu-phytoremediation, practically, Cu-phytoextraction; however, generally, the values of most calculated MRs were very low (<1, for both plants); 2) The shoots of both plants reflected soundly the current status of metal presence in the studied environment and they can be recommended for seasonal screenings of a general level of metal pollution in the areas of interest; however, specifically, they cannot reflect quite correctly the level of soil pollution; 3) Soil Cu, and As were detected in alarming concentrations.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Biodegradação Ambiental , Monitoramento Biológico , Cobre/análise , Metalurgia , Mineração , Plantas , Sérvia , Solo/química , Poluição da Água/análise
2.
Chemosphere ; 262: 127810, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32763578

RESUMO

Copper (Cu) is an essential element for humans and plants when present in lesser amount, while in excessive amounts it exerts detrimental effects. There subsists a narrow difference amid the indispensable, positive and detrimental concentration of Cu in living system, which substantially alters with Cu speciation, and form of living organisms. Consequently, it is vital to monitor its bioavailability, speciation, exposure levels and routes in the living organisms. The ingestion of Cu-laced food crops is the key source of this heavy metal toxicity in humans. Hence, it is necessary to appraise the biogeochemical behaviour of Cu in soil-plant system with esteem to their quantity and speciation. On the basis of existing research, this appraisal traces a probable connexion midst: Cu levels, sources, chemistry, speciation and bioavailability in the soil. Besides, the functions of protein transporters in soil-plant Cu transport, and the detrimental effect of Cu on morphological, physiological and nutrient uptake in plants has also been discussed in the current manuscript. Mechanisms related to detoxification strategies like antioxidative response and generation of glutathione and phytochelatins to combat Cu-induced toxicity in plants is discussed as well. We also delimits the Cu accretion in food crops and allied health perils from soils encompassing less or high Cu quantity. Finally, an overview of various techniques involved in the reclamation and restoration of Cu-contaminated soils has been provided.


Assuntos
Cobre/metabolismo , Produtos Agrícolas/fisiologia , Poluentes do Solo/metabolismo , Disponibilidade Biológica , Cobre/análise , Cobre/toxicidade , Produtos Agrícolas/metabolismo , Intoxicação por Metais Pesados , Humanos , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
3.
Chemosphere ; 262: 127843, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32777614

RESUMO

This study aimed to estimate the impact of an abandoned copper (Cu) mine on ecosystem environmental quality, using integrated ecological and biogeochemical analyses. Through a controlled experiment, the amount of Cu released by waste rocks, Cu adsorbed in soils, Cu geochemical behaviour and its leached amount were measured. Furthermore, to investigate the impacts of mine drainage on the adjacent ecosystem, samples of sediments, water and aquatic macroinvertebrates were analysed. We found that waste rocks still have high Cu concentration even after 30 years under weathering, ranging from 7782 to 8717 mg kg-1, associated mainly with carbonates, amorphous oxides and sulphides. It was estimated that 7.2 tonnes of Cu were released by waste rocks into the environment over last 30 years. The concentration of Cu observed in Ubari stream water was (


Assuntos
Cobre/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Brasil , Ecossistema , Poluição Ambiental/análise , Metais/análise , Mineração , Rios , Solo , Poluentes do Solo/análise , Sulfetos/análise
4.
Food Chem ; 334: 127563, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32791433

RESUMO

A new magnetic Cu(II) IIP (Fe3O4@IIP-IDC) is synthesized by polymerization of Imidazole-4,5-dicarboxylic acid functionalized Allyl chloride, and significant improvement of its performance has been compared. SPE parameters were optimized using Box-Behnken design to achieve the twin objectives of quantitative determination and removal of Cu(II). FLPSO kinetic model and BS isotherm model fits well with the capacity of 175 mg g-1. Analytical figures of merit includes a linearity range of 10-5,000 µg L-1 (R2 = 0.9986), preconcentration factor of 50 after eluting with 5 mL of 1 M HNO3, LOD of 1.03 µg L-1 and LOQ of 4.5 µg L-1. Accuracy was assessed by analysis of SRM (Standard Reference Material) and recovery experiments after spiking in food samples (Tea, coffee, chocolate, spinach, infant milk substitute) and battery wastewater. Ease of use, reusability (15 cycles), rapid adsorption and high selectivity makes it a promising candidate for efficient and selective removal and trace determination.


Assuntos
Cobre/análise , Análise de Alimentos/métodos , Impressão Molecular/métodos , Polímeros/química , Poluentes Químicos da Água/análise , Adsorção , Compostos Alílicos/química , Cobre/isolamento & purificação , Ácidos Dicarboxílicos/química , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Imidazóis/química , Limite de Detecção , Fenômenos Magnéticos , Águas Residuárias/análise , Poluentes Químicos da Água/isolamento & purificação
5.
Sci Total Environ ; 753: 142013, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32890867

RESUMO

Companies in the wood industry are constantly developing their outdoor products. The possibility of using bio-based chemicals as an alternative to traditional wood preservatives-regulated in Europe by The Biocidal Products Regulation No 528/2012-has been considered, but chemical leaching from the wood decreases its effectiveness and may negatively affect the environment. This study aims to compare the effectiveness of bio-based chemicals with potential use in wood preservation to commercially available preservatives, to investigate their fixation to wood and their ecotoxicity and to quantify the potentially toxic elements leached from the wood. Pyrolysis distillates of tree bark, organic acids found in distillates, Colatan GT10 tannin extract and log soaking liquid as a hardwood veneer process residue were tested and compared with commercial pine oil and a copper-based wood preservative. In the wood decay test of impregnated pine sapwood specimens, Colatan GT10 extract performed as well as the commercial wood preservatives. The same decay trial with leached specimens significantly reduced the performance of the bio-based chemicals. The results of the ecotoxicity test with photoluminescent Aliivibrio fischeri bacteria showed that many bio-based chemicals with potential use in wood preservation have markedly lower ecotoxicity than commercially available wood preservatives, but the ecotoxicity of some bio-based chemicals is higher, as in the case of some of the pyrolysis distillates. The wood preservation efficiency and the ecotoxicity of the studied chemicals had a poor correlation, implying that other factors besides treatment agent toxicity play a role in deterring fungal growth on treated wood. The amount of elemental toxins in the leachates was low. These results emphasize the importance of the chemical ecotoxicity of bio-based preservative compounds, as their detrimental effect on the environment can be higher than that of the traditional preservatives unless effectively linked to wood to prevent leaching.


Assuntos
Pinus , Madeira , Cobre/análise , Cobre/toxicidade , Europa (Continente) , Fungos , Madeira/química
6.
Bull Environ Contam Toxicol ; 105(5): 711-714, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33001235

RESUMO

The dusky grouper Epinephelus marginatus is predator fish subjected to be impacted due to the contamination of their habitats. A viable source of metal contamination, i.e., copper (Cu), in this species is the ingestion of contaminated food. The objective of this work was to verify the toxic effects of Cu contaminated feed in dusky grouper. A 15 days trial was conducted with three treatments: control, 1 g and 2 g Cu/kg of fish feed. After the trial, the gut was analyzed for Cu concentration and the liver for SOD and GST activity. The Cu concentration in the intestinal tract was significantly greater in fish from contaminated treatments when compared with control. The SOD was significantly lower in contaminated fish, and the GST did not show differences among treatments. Copper showed to be toxic for the species, as evidenced by gut accumulation and suggested by SOD response.


Assuntos
Ração Animal , Cobre/toxicidade , Conteúdo Gastrointestinal/química , Perciformes/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Cobre/análise , Ecossistema , Fígado/efeitos dos fármacos , Fígado/enzimologia , Modelos Teóricos , Alimentos Marinhos , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/análise
7.
Huan Jing Ke Xue ; 41(11): 5193-5200, 2020 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124264

RESUMO

There are complex interrelationships between plant microorganisms (phyllosphere and rhizosphere) and host plants, which can promote plant growth and enhance the tolerance of host plants to stress. In this study, we selected the dominant species Bothriochloa ischaemum as the research subject in a copper tailings dam. Using high-throughput sequencing, we investigated the structures of the fungal communities and diversities in the phyllosphere and rhizosphere of B. ischaemum. This study also explored the effects of heavy metal content on fungal community characteristics. The results showed that Ascomycota and Basidiomycota were the dominant phyla in the phyllosphere and rhizosphere of B. ischaemum. The diversities and richness of the rhizosphere fungal community were higher than that of the phyllosphere fungal community. The diversities of rhizosphere and phyllosphere fungal communities was affected by different heavy metals. Phyllosphere fungal diversity was mainly affected by the content of Zn and Cu in leaves, and the content of Pb in roots was the key factor affecting the diversity of the rhizophere fungal community. Furthermore, Pleosporaceae had a very significant positive correlation with Cd in the phyllosphere, and Nectriaceae had a significant positive correlation with Zn in the rhizosphere. These fungal communities could be used as indicators of ecological recovery in areas with heavy metal pollution. The results could provide an ecological basis for the exploration and utilization of phyllosphere or rhizosphere fungi resources during ecological restoration processes. This study also provides guidance for selecting the plant-microbial symbionts during ecological restoration in areas with heavy metal pollution.


Assuntos
Metais Pesados , Micobioma , Poluentes do Solo , Cobre/análise , Metais Pesados/análise , Rizosfera , Solo , Microbiologia do Solo , Poluentes do Solo/análise
8.
Huan Jing Ke Xue ; 41(8): 3675-3683, 2020 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124341

RESUMO

The interaction between microplastics, heavy metals, and antibiotics can lead to combined pollution, which could result in greater environmental damage. The pathway and mechanism of the interaction between microplastics, heavy metals, and antibiotics are the preconditions for evaluating the associated environmental risk; however, these are not well understood. As probe sorbates, the sorption behaviors of copper ions (Cu2+) and tetracycline (TC) on two microplastics [high density polyethylene (HPDE) and general-purpose polystyrene (GPPS)] in aqueous solution were investigated and the welding theory with relevant experimental results were discussed. The adsorption capacity of HDPE was greater than that of GPPS in a single Cu solution, whereas the reverse situation occurred in a single TC solution. Moreover, the adsorption capacity of the microplastics in a Cu2+-TC binary solution was larger than that in the single solutions. The pseudo-second-order kinetic models to describe the adsorption process were reasonable and the entire process could be divided into two phases:surface adsorption and internal diffusion. The Langmuir model provided a better fit of the data than did the Freundlich model. In the single solutions, the saturated adsorption amounts of Cu2+ and TC were 0.178 µmol·g-1 and 0.257 µmol·g-1, respectively, for GPPS, and 0.334 µmol·g-1 and 0.194 µmol·g-1, respectively, for HDPE. In the binary solution, the corresponding numerical values were 0.529 µmol·g-1 and 0.411 µmol·g-1, respectively, for GPPS and 0.471 µmol·g-1 and 0.341 µmol·g-1, respectively, for HDPE. The variations in the surface morphological characteristics and chemical functional groups were the main reasons for the difference in the adsorption behavior of microplastics. The variation of the pH of the adsorption system could change the existing forms and surface electrical properties of microplastics and adsorbed objects, and subsequently affected the equilibrium adsorption capacity. When the ambient temperature was in the range of 15 to 35℃, increasing the temperature was unfavorable for the adsorption process. Cu2+ and TC could produce a synergistic effect under the conditions of coexistence. The formation of complexes and bridging make Cu2+ and TC more easily adsorbed by microplastics.


Assuntos
Cobre , Poluentes Químicos da Água , Adsorção , Antibacterianos , Cobre/análise , Concentração de Íons de Hidrogênio , Íons , Cinética , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
9.
Water Res ; 186: 116383, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916622

RESUMO

Antifouling paints are biocidal products applied to ship and boat hulls in order to prevent the growth and settlement of marine organisms, i.e. fouling. The release of biocides from the surface of the paint film act to repel or poison potential settling organisms. Currently, the most commonly used biocide in antifouling paints is cuprous oxide. In the EU, antifouling products are regulated under the Biocidal Products Regulation (BPR), which states that the recommended dose should be the minimum necessary to achieve the desired effect. For antifouling products, the dose is measured as the release rate of biocide(s) from coating. In this study, the release rates of copper and zinc from eight different coatings for leisure boats were determined through static exposure of coated panels in four different harbors located in Swedish waters along a salinity gradient ranging from 0 to 27 PSU. The results showed the release rate of copper to increase with increasing salinity. Paints with a higher content of cuprous oxide were also found to release larger amounts of copper. The coatings' ability to prevent biofouling was also evaluated and no significant difference in efficacy between the eight tested products was observed at the brackish and marine sites. Hence, the products with high release rates of copper were equally efficient as those with 4 - 6 times lower releases. These findings suggest that current antifouling paints on the market are leaching copper in excess of the effective dose in brackish and marine waters. Additionally, the results from the freshwater site showed no benefit in applying a copper-containing paint for the purpose of fouling prevention. This indicates that the use of biocidal paints in freshwater bodies potentially results in an unnecessary release of copper. By reducing the release rates of copper from antifouling paints in marine waters and restricting the use of biocidal paints in freshwater, the load of copper to the environment could be substantially reduced.


Assuntos
Incrustação Biológica , Cobre , Incrustação Biológica/prevenção & controle , Cobre/análise , Metais , Pintura , Salinidade , Navios , Suécia
10.
Chemosphere ; 254: 126852, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957277

RESUMO

This study reports the environmental fate and ecological hazard of the three heavy metals (HMs), viz. copper (Cu), manganese (Mn) and zinc (Zn) in soil influenced by municipal solid waste (MSW) dumping. The experimental site is situated in the vicinity of Deepor Beel, a Ramsar site located in Guwahati, India. This study assessed (i) the distribution pattern of Cu, Mn and Zn in six geochemical fractionations; (ii) the mobility, bioavailability and toxicity of Cu, Mn and Zn based on eight contamination and ecological indices, and (iii) the impact of Cu, Mn and Zn on soil quality. Altogether, 18 soil samples were collected and analysed from the study site using stratified random sampling. Pollution indices and multivariate statistics were applied on the data to identify the level and source of analysed HMs. Sequential extraction has revealed that the binding strength of Cu, Mn and Zn had a uniform trend. Mobility and potential bioavailability of studied HMs were in the order Mn > Cu > Zn. Analysed HMs were dominantly associated with non-bioavailable fractions. The observed low values of various contamination factors indicated the lesser contamination load posed by these metals. Conversely, their high enrichment factor and geo-accumulation index values indicated the sources of these metals were anthropogenic. Overall, the pollution and ecological indices registered lower contamination. Yet, it would be prudent to adopt efficient MSW management strategies for eliminating any future risk emanating out of this dumping site and posing threat to nearby Deepor Beel and its associated flora and fauna.


Assuntos
Metais Pesados/análise , Medição de Risco , Poluentes do Solo/análise , Cobre/análise , Monitoramento Ambiental , Poluição Ambiental/análise , Índia , Manganês/análise , Zinco/análise
11.
PLoS One ; 15(9): e0239732, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986774

RESUMO

A large assemblage (n = 307) of architectural glasses (tesserae and windows) from the early 8th-century Umayyad residential site at Khirbat al-Minya was analysed by laser ablation inductively coupled plasma mass spectrometry. Trace element patterns are essential to establish the provenance of the base glass, while the comparative evaluation of the colouring and opacifying additives allow us to advance a production model for the manufacture of glass mosaic tesserae during the early Islamic period. The primary glass types are Levantine I and Egypt 1a, as well as a few older, reused tesserae, and Mesopotamian plant ash glass used for amber-coloured window fragments. Chemical data revealed fundamental differences in the colouring and opacification technologies between the Egyptian and Levantine tesserae. Co-variations of lead and bismuth, and copper, tin and zinc in the Egypt 1a tesserae provide first evidence for the production of different mosaic colours in a single workshop, specialising in the manufacture of tesserae of different colours. No such trend is apparent in the Levantine samples. Red, cobalt blue and gold leaf tesserae were found to be exclusively made from a Levantine base glass, indicating that the generation of some colours may have been a specialised process. The same may apply to the amber-coloured window glass fragments of Mesopotamian origin that exhibit very unusual characteristics, combining elevated copper (2% CuO) with an excess in iron oxide (5% Fe2O3). These findings have significant implications for the production model of strongly coloured glass and the exploitation of resources during the early Islamic period.


Assuntos
Arquitetura/história , Vidro/química , Vidro/história , Cor , Corantes/análise , Cobre/análise , Egito , Compostos Férricos/análise , História do Século XVIII , Chumbo/análise , Espectrometria de Massas/métodos , Oriente Médio , Minerais/análise , Estanho/análise , Oligoelementos/análise
12.
Ecotoxicol Environ Saf ; 202: 110913, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800248

RESUMO

Soil is considered as a sink for heavy metals. Human health is severely affected by the continuous intake of toxic heavy metals even in a very low concentration. In the present experiment, we determined the influence of nutritional status including control (fasted condition), glucose (fed state), plant protein (fed state), animal protein (fed state) and calcium (fed state) on soil cadmium (Cd) and copper (Cu) bioaccessibility using physiologically-based extraction test (PBET) method together with simulator of the human intestinal microbial ecosystem (SHIME) model. The bioaccessibility of Cd was 1.06-73.58%, 0.44-54.79% and 0-17.78% and Cu was 3.81-67.32%, 4.98-71.14%, and 0-17.54% in the phase-I, phase-II and Phase-III respectively (in this study gastric phase, small intestinal phase and colon phase were considered as phase-I, phase-II and Phase-III respectively). The outcomes showed that, the average Cd bioaccessibility was higher with animal protein addition compared with other treatments in different phases. So, the effect of animal protein on Cd bioaccessibility was higher than other treatments in the phase-I, phase-II and phase-III. Due to the addition of plant protein, the higher average bioaccessibility of Cu was noticed in phase-I and phase-II in comparison to other treatments. However, in phase-III, the higher average bioaccessibility of Cu was found due to control treatment comparing with other treatments. Therefore, the influence of plant protein was higher than other nutrients on Cu bioaccessibility in the phase-I and phase-II. Moreover, other nutrients showed variable influence on Cd and Cu bioaccessibility. So, nutritional status has a significant effect on bioaccessibility as well as human health risk assessment.


Assuntos
Cádmio/análise , Cobre/análise , Poluentes do Solo/análise , Ecossistema , Monitoramento Ambiental/métodos , Poluição Ambiental , Humanos , Intestinos/química , Metais Pesados , Nutrientes , Solo
13.
Aquat Toxicol ; 227: 105604, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32846286

RESUMO

River sediment is the ultimate sink for heavy metal pollution. Copper (Cu) and zinc (Zn) are consistently found at environmentally significant levels in sediments worldwide. We hypothesized that the bioavailability and potential ecological risk of Cu and Zn in river sediments may be affected by seasonal variations and spatial distribution. In this study, we tested our hypothesis using highly industrialized river sediments (Laojie River) as an example. The concentration of heavy metals, pollution indexes, and risk indexes were evaluated and multivariate statistical analyses were performed. We found that seasonal variations affect heavy metal contamination, pollution indexes, and potential ecological risk in sediments and this effect was more severe in the dry season. In addition, higher levels of metal contamination, pollution indexes, and potential ecological risk were observed midstream and downstream of the Laojie River. We found that Cu and Zn were the primary contaminants in Laojie River sediments and may originate from common anthropogenic sources. Analysis of the chemical fractions further revealed that Cu and Zn exhibited high mobility and potential bioavailability risk. In addition, a high percentage and amount of Cu and Zn were found in exchangeable fractions, suggesting they pose a great risk to aquatic organisms. Our results indicate that seasonal variations and spatial distribution affect the bioavailability and potential ecological risk of Cu and Zn in river sediments. These findings suggest that seasonal variations and spatial distribution are important parameters to consider for environmental monitoring and environmental management in aquatic environments.


Assuntos
Cobre/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Zinco/análise , Disponibilidade Biológica , China , Poluição Ambiental/análise , Sedimentos Geológicos/química , Metais Pesados/análise , Medição de Risco , Rios/química , Estações do Ano , Poluentes Químicos da Água/toxicidade
14.
Ecotoxicol Environ Saf ; 205: 111173, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32853866

RESUMO

Fulvic acids (FA) are one of the components of humic substances and play an important role in the interaction with metallic species and, consequently, the bioavailability, distribution and toxicity of metals. However, only a few studies have investigated these FA properties in specific environment, such as anthropogenic soils. Therefore, knowledge about FA molecular composition as well as the FA-metal interaction is essential to predict their behavior in the soil. For this reason, the aim of this study was to investigate the molecular composition of FA extracted from two sites in an anthropogenic soil (Terra Mulata), from the Amazon region, as well as their interactions with Cu(II) ions as a model. Results from 13C NMR, infrared and elemental analysis showed that these FA are composed mostly by alkyl structures and oxygen-functional groups, e.g., hydroxyl, carbonyl and carboxyl. The interaction with Cu(II) ions was evaluated by fluorescence quenching, in which the FA showed both high quantity of complexing sites per gram of carbon and good affinity to interact with the metal when compared with other soil FA. The results showed that the complexation capacity was highly correlated by the content of functional groups, while the binding affinity was largely influenced by structural factors. In addition, through the lifetime decay given by time-resolved fluorescence, it was concluded that static quenching took place in FA and Cu(II) interaction with the formation of a non-fluorescent ground-state complex. Therefore, this fraction of soil organic matter will fully participate in complexation reactions, thereby influencing the mobility and bioavailability of metal in soils. Hence, the importance of the study, and the role of FA in the environment, can be seen especially in the Amazon, which is one of the most important biomes in the world.


Assuntos
Benzopiranos/análise , Complexos de Coordenação/análise , Cobre/análise , Substâncias Húmicas/análise , Poluentes do Solo/análise , Solo/química , Benzopiranos/química , Disponibilidade Biológica , Brasil , Carbono/análise , Complexos de Coordenação/química , Cobre/química , Fluorescência , Íons , Modelos Teóricos , Poluentes do Solo/química
15.
Int J Phytoremediation ; 22(14): 1505-1514, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32643383

RESUMO

Widely used as wood preservatives for the last century, Pentachlorophenol (PCP) and chromated copper arsenate (CCA) have been shown to leach from treated surfaces and contaminate soil of wood storage sites. We performed a four-year field phytoremediation trial in southern Quebec (Canada) on a site contaminated with PCP and CCA with the following objectives: (1) assess the potential of willow, fescue, alfalfa and Indian mustard to tolerate and translocate CCA and PCP residues in their aerial tissues, (2) investigate the possibility of phytoextraction of dioxins and furans, and (3) test the effect of nitrogen fertilizer on phytoremediation performance. We showed that while nitrogen fertilization increased the chlorophyll content of plants, it did not result in a significantly greater plant biomass. We also showed that plants grown in the presence of PCP/CCA residues were able to translocate and concentrate trace elements in their aerial tissues, but also dioxins and furans (PCDD/F). This suggests that plants grown on sites polluted by PCP might contain dioxins and furans and should be treated as contaminated by these toxic chemicals. Finally, the reduction of soil contaminants at the end of the trial suggests that phytoremediation is a promising approach for decontaminating such sites.


Assuntos
Arsênico , Dioxinas , Furanos , Poluentes do Solo , Arseniatos , Arsênico/análise , Biodegradação Ambiental , Canadá , Cromo/análise , Cobre/análise , Dioxinas/análise , Quebeque , Solo , Poluentes do Solo/análise , Madeira
16.
Chemosphere ; 260: 127574, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32688316

RESUMO

Artisanal and small-scale gold mining (ASGM) operations are major contributors to the Philippines' annual gold (Au) output (at least 60%). Unfortunately, these ASGM activities lacked adequate tailings management strategies, so contamination of the environment is prevalent. In this study, soil contamination with copper (Cu), lead (Pb), zinc (Zn) and arsenic (As) due to ASGM activities in Nabunturan, Davao de Oro, Philippines was investigated. The results showed that ASGM-impacted soils had Cu, Pb, Zn and As up to 3.6, 83, 73 and 68 times higher than background levels, respectively and were classified as 'extremely' polluted (CD = 30-228; PLI = 5.5-34.8). Minerals typically found in porphyry copper-gold ores like pyrite, chalcopyrite, malachite, galena, sphalerite and goethite were identified by XRD and SEM-EDS analyses. Furthermore, sequential extraction results indicate substantial Cu (up to 90%), Pb (up to 50%), Zn (up to 65%) and As (up to 48%) partitioned with strongly adsorbed, weak acid soluble, reducible and oxidisable fractions, which are considered as 'geochemically mobile' phases in the environment. Although very high Pb and Zn were found in ASGM-impacted soils, they were relatively immobile under oxidising conditions around pH 8.5 because of their retention via adsorption to hydrous ferric oxides (HFOs), montmorillonite and kaolinite. In contrast, Cu and As release from the historic ASGM site samples exceeded the environmental limits for Class A and Class C effluents, which could be attributed to the removal of calcite and dolomite by weathering. The enhanced desorption of As at around pH 8.5 also likely contributed to its release from these soils.


Assuntos
Mineração , Poluentes do Solo/análise , Poluentes do Solo/química , Solo/química , Arsênico/análise , Arsênico/química , Cobre/análise , Cobre/química , Ouro/análise , Ferro/química , Compostos de Ferro/química , Chumbo/análise , Chumbo/química , Minerais/química , Filipinas , Sulfetos/química , Difração de Raios X , Zinco/análise , Zinco/química
17.
Bull Environ Contam Toxicol ; 105(2): 299-306, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32653945

RESUMO

Impacts on urban water resources are invariably caused by the development of urban centers and the occupation of the watershed. The release of untreated effluents and urban runoff are sources of metals in adjacent water bodies. It is therefore important to conduct studies on the occurrence of these trace elements in the environment and the risks posed to human health. The aim of the present study was to determine Cd, Pb, Cu, and Zn concentrations in water bodies located in the Bacanga and Cachorros watersheds and correlate the occurrence of these elements with physicochemical variables of the water (temperature, pH, dissolved oxygen, and electrical conductivity). The variables were determined at the collection site with the aid of a multiparameter kit. Heavy metal concentrations were determined using anodic stripping voltammetry. The results revealed that the streams were not contaminated with the metals analyzed. The only exception was copper in the Limoeiro and Murtura streams, both of which are located in the industrial complex.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes Químicos da Água/análise , Brasil , Cobre/análise , Humanos , Temperatura
18.
Environ Pollut ; 266(Pt 2): 115141, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32659625

RESUMO

Australian tropical freshwaters can experience extreme seasonal variability in rainfall and run off, particularly due to pulse events such as storms and cyclones. This study investigated how seasonal variability in dissolved organic matter (DOM) quality impacted the chronic toxicity of copper to a tropical green alga (Chlorella sp.) in the presence of two concentrations of DOM (low: ∼2 mg C/L; high: ∼10 mg C/L) collected from three tropical waters. Copper speciation and lability were explored using diffusive gradients in thin-films (DGT) and modelled maximum dynamic concentrations (cdynmax) using data derived from the Windermere Humic Aqueous Model (WHAM VII). Relationships between copper lability and copper toxicity were assessed as potential tools for predicting toxicity. Copper toxicity varied significantly with DOM concentration, source and season. Copper toxicity decreased with increasing concentrations of DOM, with 50% growth inhibition effect concentrations (EC50) increasing from 1.9 µg Cu/L in synthetic test waters with no added DOM (0.34 mg C/L) up to 63 µg Cu/L at DOM concentrations of 9.9 mg C/L. Copper toxicity varied by up to 2-fold between the three DOM sources and EC50 values were generally lower in the presence of wet season DOM compared to dry season DOM. Linear relationships between DGT-labile copper and dissolved copper were significantly different between DOM source, but not concentration or season. Modelled cdynmax consistently under-predicted labile copper in high DOM treatments compared to DGT measurements but performed better in low DOM treatments, indicating that this method is DOM-concentration dependent. Neither speciation method was a good surrogate for copper toxicity in the presence of different sources of natural DOM. Our findings show that DOM source and season, not just DOM concentration, affect copper toxicity to freshwater biota. Therefore, DOM quality should be considered as a toxicity-modifying factor for future derivation of bioavailability-based site-specific water quality guideline values.


Assuntos
Chlorella , Microalgas , Poluentes Químicos da Água/análise , Austrália , Cobre/análise , Água Doce , Estações do Ano
19.
Chemosphere ; 260: 127505, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32683021

RESUMO

Competitive and non-competitive batch experiments were conducted on flax fibers to study Zn2+, Cu2+, and Pb2+ ions biosorption performance. Biosorption efficiency was dependent on contact time, pH, and biosorbent concentration. The results under competitive conditions were different from those obtained in non-competitive form. A high affinity of lead, with a selectivity sequence in general of Pb > Cu > Zn was observed. The biosorption data fitted very well the Langmuir model for lead in both types of solutions and for zinc and copper in the monometal form. The fit with the Freundlich model was not as successful, except for copper in the ternary system. Regarding zinc under competitive conditions, the sorption process was quite difficult and thus the equilibrium data could not fit well the adsorption models. The maximum adsorption capacities (mmol.kg-1) were respectively 112, 122 and 71, for Pb, Cu and Zn in the single metal ion solution and 82, 57 and 8 only in the ternary, showing thus a high competition between metal ions when added simultaneously. Overall, lead could still be efficiently removed in spite of the presence of other ions while zinc would be overcome in the presence of lead and copper.


Assuntos
Cobre/análise , Linho/química , Chumbo/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zinco/análise , Adsorção , Concentração de Íons de Hidrogênio , Limite de Detecção , Modelos Teóricos , Soluções , Propriedades de Superfície
20.
Ecotoxicol Environ Saf ; 203: 110979, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678758

RESUMO

Recent EFSA (European Food Safety Authority) reports highlighted that the ecological risk assessment of pesticides needed to go further by taking more into account the impacts of chemicals on biodiversity under field conditions. We assessed the effects of two commercial formulations of fungicides separately and in mixture, i.e., Cuprafor Micro® (containing 500 g kg-1 copper oxychloride) at 4 (C1, corresponding to 3.1 mg kg-1 dry soil of copper) and 40 kg ha-1 (C10), and Swing® Gold (50 g L-1 epoxiconazole EPX and 133 g L-1 dimoxystrobin DMX) at one (D1, 5.81 10-2 and 1.55 10-1 mg kg-1 dry soil of EPX and DMX, respectively) and ten times (D10) the recommended field rate, on earthworms at 1, 6, 12, 18 and 24 months after the application following the international ISO standard no. 11268-3 to determine the effects on earthworms in field situations. The D10 treatment significantly reduced the species diversity (Shannon diversity index, 54% of the control), anecic abundance (29% of the control), and total biomass (49% of the control) over the first 18 months of experiment. The Shannon diversity index also decreased in the mixture treatment (both fungicides at the recommended dose) at 1 and 6 months after the first application (68% of the control at both sampling dates), and in C10 (78% of the control) at 18 months compared with the control. Lumbricus terrestris, Aporrectodea caliginosa, Aporrectodea giardi, Aporrectodea longa, and Allolobophora chlorotica were (in decreasing order) the most sensitive species to the tested fungicides. This study not only addressed field ecotoxicological effects of fungicides at the community level and ecological recovery, but it also pinpointed some methodological weaknesses (e.g., regarding fungicide concentrations in soil and statistics) of the guideline to determine the effects on earthworms in field situations.


Assuntos
Cobre/toxicidade , Monitoramento Ambiental/métodos , Compostos de Epóxi/toxicidade , Fungicidas Industriais/toxicidade , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Triazóis/toxicidade , Animais , Biodiversidade , Biomassa , Cobre/análise , Ecotoxicologia , Compostos de Epóxi/análise , Fungicidas Industriais/análise , Oligoquetos/crescimento & desenvolvimento , Medição de Risco , Solo/química , Poluentes do Solo/análise , Triazóis/análise
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