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1.
Water Res ; 200: 117274, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34102386

RESUMO

Humans and wildlife are frequently exposed to complex mixtures of chemicals, with exposure rarely causing only one dominant effect. Consequently, there is an urgent need to develop strategies to assess exposures to multiple, hazardous chemicals and effects of such combinations. Here, the maximum cumulative ratio was used as part of a tiered approach to evaluate and prioritize risks of co-exposures to metals in 781 samples of surface water from Tai Lake, China. Multiple metals, including copper, lead, cadmium, nickel and zinc dominated the hazardous effects on aquatic organisms. Based on species sensitivity distributions developed from genus mean chronic values, crustaceans were the most susceptible to effects of metals. Results of a multi-generation experiment demonstrated adverse effects of mixtures of metals at environmentally relevant concentrations on growth and reproduction of the cladocerans, Daphnia magna and Moina macrocopa. Specifically, when exposed to metals body length and total number of offspring produced per adult female were less than the controls. Resistance of D. magna populations to mixtures of metals was significantly less, while, under similar conditions, M. macrocopa exhibited greater capacity to recover and the response to adverse effects occurred earlier. Demographic analysis models constructed using a Leslie matrix, used to predict population dynamics of the cladocerans, revealed that various effects of metal cocktails on individual-level endpoints was related to attenuation at the population level. By integrating all the observations, it was recommended that densities of populations of cladocerans in surface waters could be a useful parameter for indicating possible detrimental effects induced by toxic chemicals. Results of this study provide novel insights into risks posed by simultaneous exposure to multiple metals and reveal their potential adverse long-term effects on sensitive aquatic organisms.


Assuntos
Poluentes Químicos da Água , Animais , China , Daphnia , Feminino , Humanos , Metais/análise , Metais/toxicidade , Medição de Risco , Poluentes Químicos da Água/toxicidade
2.
Food Chem ; 362: 130168, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34090045

RESUMO

Multielement analysis and chemometric methods were proposed to discriminate the Sorrento lemon (PGI) juices according to geographical origin. In 2018 and 2019, 169 fruits from three farms in PGI area and two in not-PGI area were collected and analysed for essential and not-essential elements by ICP-MS. The PCA of multielement fingerprinting grouped lemon juices from PGI farms revealing a strong differentiation at small geographical scale. The S-LDA discriminated lemon juices for Mo, Ba, Rb, Mg, Co, Ca, Fe, Sr on the two production years, giving 97.7% correct classification, 98.5% accuracy and 93.8% external validation. The good correlation lemon juice vs cultivation soil and the soil discrimination by not-essential elements suggested the use of these elements as reliable indicators of lemon juice provenances. Despite lowering the number of variables, constituted by not-essential elements Ba, Rb, Ti, Co, the use of S-QDA discriminated the lemons juices with 87.5% accuracy and 83.9% validation.


Assuntos
Citrus/química , Análise de Alimentos/métodos , Metais/análise , Solo/química , Quimioinformática/métodos , Análise Discriminante , Análise de Alimentos/estatística & dados numéricos , Frutas/química , Sucos de Frutas e Vegetais/análise , Itália
3.
Food Chem ; 362: 130176, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111692

RESUMO

In the present work, multivariate designs were used to optimize an alkaline dissolution, assisted by ultrasound energy, procedure of goat meat using tetramethylammonium hydroxide (TMAH) aiming to determine Ca, Cu, Fe, K, Mg, Na and Zn by flame atomic absorption (FAAS) and emission (FAES) spectrometry. The optimal conditions found for the dissolution were in the following ranges: 0.4-0.5 g for the sample mass, 12-15 min of sonication and using 700-1000 µL of 25% TMAH at a temperature of 50 °C. The obtained limits of quantification varied between 0.221 (Mg) and 7.60 (Ca) µg g-1. Accuracy was assessed by comparing the results obtained by applying the proposed method with the digestion in an acid medium using a digesting block and by analyzing bovine liver certified reference material. The application of a t-test revealed that, at a 95% confidence level, there were no significant differences between the values obtained.


Assuntos
Análise de Alimentos/métodos , Carne/análise , Metais/análise , Espectrofotometria Atômica/métodos , Animais , Análise de Alimentos/estatística & dados numéricos , Cabras , Análise Multivariada , Compostos de Amônio Quaternário/química , Solubilidade , Espectrofotometria Atômica/estatística & dados numéricos , Temperatura
4.
Chemosphere ; 280: 130677, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33964762

RESUMO

There is growing evidence that e-waste recyclers may be exposed to potentially high levels of metals though associations between such exposures and specific work activities is not well established. In addition, studies have focused on metals traditionally biomonitored and there is no data on the exposure of recyclers to elements increasingly being used in new technologies. In the current study, levels of metals were measured in blood and urine of e-waste recyclers at Agbogbloshie (Ghana) and a control group. Blood and urine samples (from 100 e-waste recyclers and 51 controls) were analyzed for 17 elements (Ag, As, Ba, Cd, Ce, Cr, Eu, La, Mn, Nd, Ni, Pb, Rb, Sr, Tb, Tl, Y) using the ICP-MS. Most e-waste recyclers reported performing at least 4 different tasks in decreasing order as e-waste dismantling (54%), trading/selling of e-waste (45%), burning wires only (40%), and collecting wires after burning (34%). Mean levels of blood Pb, Sr, Tl, and urinary Pb, Eu, La, Tb, and Tl were significantly higher in recyclers versus controls. In general, the collectors and sorters tended to have higher elemental levels than other work groups. Blood Pb levels (mean 92.4 µg/L) exceeded the U.S. CDC reference level in 84% of the e-waste recyclers. Likewise, blood Cd, Mn, and urinary As levels in recyclers and controls were higher than in reference populations elsewhere. E-waste recyclers are exposed to metals traditionally studied (e.g., Pb, Cd, As) and several other technology-critical and rare earth elements which previously have not been characterized through human biomonitoring.


Assuntos
Resíduo Eletrônico , Monitoramento Biológico , Resíduo Eletrônico/análise , Monitoramento Ambiental , Gana , Humanos , Metais/análise , Reciclagem
5.
Environ Sci Technol ; 55(11): 7355-7364, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33973770

RESUMO

An increased risk of adverse biological effects of metals in sediments may be accompanied by high labile metal fluxes as measured by the diffusive gradients in thin films (DGT) technique. To improve the usefulness of the DGT technique for sediment quality risk assessments, we used the simpler and more cost-effective piston DGTs rather than planar DGT probes to measure bioavailable metal fluxes in naturally contaminated sediments with widely varying composition (properties, metals and concentrations) and assessed their prediction of toxicity to amphipod reproduction in a flow-through microcosm. DGT pistons were deployed in sediments under different conditions, both in the field (in situ) and in the laboratory in sediment cores (lab-equilibrated) and in homogenized sediments (lab-homogenized). We demonstrated that the metal flux toxic units, DGTTU, measured in situ best predicted the magnitude of toxicity to amphipod reproduction. For sediments that had been highly disturbed before testing, DGTTU were less predictive for observed toxicity, but the copper flux alone (DGTTU-Cu) was effective, indicating copper was the primary cause of toxicity in these highly perturbed sediments. Overall, our study highlighted that the adverse effects induced by excessive bioavailable metals in contaminated sediments can be consistently sensed by the DGT pistons.


Assuntos
Sedimentos Geológicos , Poluentes Químicos da Água , Disponibilidade Biológica , Monitoramento Ambiental , Metais/análise , Metais/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
6.
Environ Monit Assess ; 193(6): 348, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34018048

RESUMO

The change in the water quality of rainfall impacts water supply through the contamination of surface water and groundwater. The presence of potential sources for metals in the form of aerosol through atmospheric transportation from gold tailings dams, coal mines, and coal-fired power stations increases the risk of water quality deterioration in the Johannesburg region. Rainfall monitoring was conducted for one hydrological year. Rainfall amount was measured, and samples were collected for stable isotope and metal analysis. Some metals show very high concentration in the rainfall with a decreasing order from zinc, cadmium, copper to lead. Their presence in the water is not desirable, as a result of favourable pH and Eh conditions in the rainfall with contaminant inputs from the gold tailing dams, coal mines, and coal-fired power stations. Therefore, the Johannesburg rainfall can be considered as potentially toxic due to the constant input of meals into water supply dams and aquifers recharged by the rainfall.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Carvão Mineral/análise , Metais/análise , África do Sul
7.
Mar Pollut Bull ; 168: 112472, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34004480

RESUMO

This study comprises the first record of a juvenile Giant Devil Ray specimen for Rio de Janeiro, Southeastern Brazil, and its metal and metalloid contents. A scientometric assessment was also performed for the Manta and Mobula genera. Only five records were found, and only As, Cd, Pb, Hg, Pt, Pd and Rh have been assessed. All studies but one concerned human consumption. A significant knowledge gap on metal and metalloid ecotoxicology for mobulid rays is noted, indicating the emergence of a new field of research that th may be applied for wildlife conservation and management in response to anthropogenic contamination. Our study is also the first to provide Al, Cr, Cu, Fe, Mn, Sr, Ti, V and Zn contents for muscle, liver, brain and kidney for a mobulid ray and one of the scarce reports concerning As, Cd, Hg and Pb in muscle, liver and kidney.


Assuntos
Elasmobrânquios , Metaloides , Metais Pesados , Animais , Brasil , Ecotoxicologia , Monitoramento Ambiental , Humanos , Metaloides/análise , Metais/análise , Metais Pesados/análise
8.
J Environ Manage ; 292: 112824, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34033987

RESUMO

Phytomanagement is considered a suitable option in line with nature-based solutions to reduce environmental risks associated to metal(loid) mine tailings. We aimed at assessing the effectiveness of biochar from pruning trees combined with compost from urban solid refuse (USR) to ameliorate the conditions of barren acidic (pH ~5.5) metal(loid) mine tailing soils (total concentrations in mg kg-1: As ~220, Cd ~40, Mn ~1800, Pb ~5300 and Zn ~8600) from Mediterranean semiarid areas and promote spontaneous plant colonization. Two months after amendment addition were enough to observe improvements in chemical and physico-chemical tailing soil properties (reduced acidity, salinity and water-soluble metals and increased organic carbon and nutrients content), which resulted in lowered ecotoxicity for the soil invertebrate Enchytraeus crypticus. Recalcitrant organic carbon provided by biochar remained in soil whereas labile organic compounds provided by USR were consumed over time. These improvements were consistent for at least one year and led to lower bulk density, higher water retention capacity and higher scores for microbial/functional-related parameters in the amended tailing soil. Spontaneous growth of native vegetation was favored with amendment addition, but adult plants of remarkable size were only found after three years. This highlights the existence of a time-lag between the positive effects of the amendment on tailing soil properties being observed and these improvements being translated into effective spontaneous plant colonization.


Assuntos
Poluentes do Solo , Carvão Vegetal , Metais/análise , Solo , Poluentes do Solo/análise
9.
Biomed Res Int ; 2021: 6678931, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33869633

RESUMO

Information on the content of medicinal plants used in the treatment of diabetes is scarce in the literature. The objectives of this study were to determine the levels of macroelements and microelements in three different medicinal plant species including the dry samples and teas from Bauhinia forficata, Eleusine Indica, and Orthosiphon stamineus and assess the human health risks of ingestion of the tea. The content of the dry samples and teas was obtained using the technique of inductively coupled plasma optical emission spectrometry (ICP OES) after microwave digestion procedure. The hazard quotient (HQ) method was used to access the human health risks posed by heavy metal through tea consumption. The results revealed the presence of K, Mg, Na, P, Al, Fe, Zn, Mn, Cu, Ni, and Se in dry samples and plant teas. The dry plants have high concentration of K and P. All dry plants contain Mg, Na, Al, Fe, Mn, Ni, Zn, and Cu above the limit permissible level set by the World Health Organization (WHO). All the hazard index (HI) values in plant teas were found to be within safe limits for human consumption (HI < 1). The plants may have possible action benefits when used in popular medicine. However, the ingestion through capsules prepared by enclosing a plant powder or teas can be harmful to the health of diabetics. The prescription of this plant for the treatment of diabetes should be treated with caution.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Elementos Químicos , Plantas Medicinais/química , Humanos , Limite de Detecção , Metais/análise , Micro-Ondas , Minerais/análise , Folhas de Planta/química , Fatores de Risco , Espectrofotometria Atômica
10.
Sci Total Environ ; 779: 146423, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-33752014

RESUMO

The monitoring of soil metal(loid) contamination is of global significance due to deleterious effects that metal(loid)s have on living organisms. Soil biological properties such as enzyme activities (EAs) are good indicators of metal(loid) contamination due to their high sensitivity, fast response, and low-cost. Here, the effect of metal(loid) contamination on physicochemical properties and microbial functionality in soils sampled from within 10 km of a Cu smelter is investigated. Soil composite samples were randomly taken within 2, 4, 6, 8 and10 km zones from a mining industry Cu smelter. The EAs of dehydrogenase (DHA), arylsulfatase (ARY), ß-glucosidase, urease, and arginine ammonification (AA) were studied as indicators of metal(loid) contamination, which included the ecological dose (ED50) with respect to Cu and As contents. The community level physiological profile (CLPP), functional diversity, and catabolic evenness were evaluated based on the C-substrate utilisation. All EAs decreased in zones with high degrees of metal(loid) contamination, which also had low TOC and clay contents, reflecting long term processes of soil degradation. Positive and strong relationships between EAs and TOC were found. DHA and ARY activities decreased by approximately 85-90% in highly metal(loid) contaminated soils. DHA and AA showed significant ED50 values associated with available Cu (112.8 and 121.6 mg CuDTPA kg-1, respectively) and total As contents (30.8 and 31.8 mg As kg-1, respectively). The CLPP showed different metabolic profiles along the metal(loid) contamination gradients. Long-term stress conditions in soils close to industrial areas resulted in the decreasing of general biological activity, catabolic capacity, and functional diversity.


Assuntos
Metais Pesados , Poluentes do Solo , Cobre/análise , Monitoramento Ambiental , Poluição Ambiental , Metais/análise , Metais Pesados/análise , Solo , Poluentes do Solo/análise
11.
Mar Pollut Bull ; 166: 112267, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33752157

RESUMO

The role of Fe oxyhydroxides dynamic on metal bioavailability was studied in the Rio Doce estuary after the largest mining disaster in the world. Soon after the disaster in 2015, metals were associated with Fe oxyhydroxides under a redox-active estuarine environment. Our results indicate that organic matter inputs from plant colonization on deposited tailings over estuarine soils led to a reductive dissolution of Fe oxyhydroxides within two years. Soil pseudo-total Fe content decreased by 70% between 2015 and 2017, while the total metal contents (Cr, Cu, Ni, Pb, and Zn) decreased by 79% in the soil. The losses of Fe and metals coupled to changes in Fe oxides crystallinity reveal a future ephemeral control of Fe oxyhydroxides over metal immobilization. Our results suggest a potential chronic contamination at the estuary and points to an aggravating scenario for the following years due to the increasing dominance of poorly crystalline Fe oxyhydroxides.


Assuntos
Desastres , Metais Pesados , Poluentes do Solo , Monitoramento Ambiental , Estuários , Metais/análise , Metais Pesados/análise , Mineração , Solo , Poluentes do Solo/análise
12.
J Environ Sci Health B ; 56(4): 396-414, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33691593

RESUMO

The element concentrations in the fruitbodies of Leccinum scabrum from two forested upland sites and one lowland site of different geochemical background were compared to topsoil concentrations. The aim of the study was to establish baseline concentration datasets, gain insight into the species' bioconcentration potential and to assess the impact of anthropogenic factors. The validated methods for analysis include inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and cold-vapor atomic absorption spectroscopy (CV-AAS). Bioinclusion (bioconcentration factor > 1) by L. scabrum was observed for the elements Ag, Cd, Cu, K, Hg, Mn, Na, Mg, P, Rb, and Zn. In contrast, the elements Al, Ba, Ca, Fe, Ni, and Sr as well as the toxic Pb were bioexcluded. Among these elements, the toxic elements Cd and Pb are noteworthy regarding the aspect of human mushroom consumption. The medians of Cd in caps of L. scabrum from the upland sites were in the range of 5.6-6.6 mg kg-1 dm, with a maximum in an individual sample of 14 mg kg-1 dm, which is in the range of concentrations reported previously for polluted soils. Lead concentrations were much lower, with medians in the range of 0.79-1.3 mg kg-1 dm in caps and 0.48-0.59 mg kg-1 dm in stipes. Mineral contents of L. scabrum appear to be the result of a complex interaction of a species' characteristic physiology with local mineral soil geochemistry and with anthropogenic pollution factors.


Assuntos
Basidiomycota/química , Minerais/análise , Solo/química , Basidiomycota/metabolismo , Bioacumulação , Cádmio/análise , Monitoramento Ambiental/métodos , Contaminação de Alimentos/análise , Florestas , Humanos , Mercúrio/análise , Metais/análise , Metais/farmacocinética , Polônia , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética , Espectrofotometria Atômica , Distribuição Tecidual , Oligoelementos/análise
13.
Environ Geochem Health ; 43(4): 1385-1400, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33687604

RESUMO

This paper proposes the use of wetlands as a phytoremediation strategy for areas of mining and maritime influence in the southeast of Spain. Potentially toxic elements (PTEs) tolerant and salinity-resistant macrophytes (Phragmites australis, Juncus effusus and Iris pseudacorus) have been used. The experiment is carried out in an aerobic artificial wetland using representative sediments affected by mining activities in the study area. Selected species were placed in pots containing substrates made with different mixtures of topsoil and/or peat, mining residues (black or yellow sand). After six months, rhizosphere, root and aerial parts were collected. A transfer study of As, Pb, Zn and Cu is performed, determining contents in rhizosphere and plant (aerial and underground part). From these data, the TF and BCF were calculated for each plant in 15 different substrates. The work is complemented by an initial study of scanning electron microscopy (SEM-EDX) of plants. The obtained results indicate a tolerance of the metallophytes to these PTEs, which may favour the obtaining of a naturalized habitat that acts as an effective protective barrier to the ecosystem, that is easy to maintain and that avoid the risk of transfer to the trophic chain. The use of these species can be a complement to the chemical stabilization proposed for the whole area and carried out in experimental plots. Because they are perennial plants, it is necessary to continue with the experiments and obtain results in a longer period of time that allows to evaluate yield and stabilization.


Assuntos
Biodegradação Ambiental , Metais/farmacocinética , Plantas/metabolismo , Poluentes do Solo/farmacocinética , Áreas Alagadas , Compostos de Cálcio , Ecossistema , Concentração de Íons de Hidrogênio , Iris (Planta)/química , Iris (Planta)/metabolismo , Metais/análise , Metais/toxicidade , Mineração , Óxidos , Plantas/química , Poaceae/química , Poaceae/metabolismo , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Espanha
14.
Environ Pollut ; 276: 116721, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33601199

RESUMO

Historical mining activities cause widespread, long-term trace metal contamination of freshwater ecosystems. However, measuring trace metal bioavailability has proven difficult, because it depends on many factors, not least concentrations in water, sediment and habitat. Simple tools are needed to assess bioavailabilities. The use of biomonitors has been widely advocated to provide a realistic measure. To date there have been few attempts to identify ubiquitous patterns of trace metal accumulation within and between freshwater biomonitors at geographical scales relevant to trace metal contamination. Here we address this through a nationwide collection of freshwater biomonitors (species of Gammarus, Leuctra, Baetis, Rhyacophila, Hydropsyche) from 99 English and Welsh stream sites spanning a gradient of high to low trace metal loading. The study tested for inter-biomonitor variation in trace metal body burden, and for congruence amongst accumulations of trace metals within taxa and between taxa across the gradient. In general, significant differences in trace metal body burden occurred between taxa: Gammarus sp. was the most different compared with insect biomonitors. Bivariate relationships between trace metals within biomonitors reflected trace metal profiles in the environment. Strong correlations between some trace metals suggested accumulation was also influenced by physiological pathways. Bivariate relationships between insect biomonitors for body burdens of As, Cu, Mn and Pb were highly consistent. Our data show that irrespective of taxonomic or ecological differences, there is a commonality of response amongst insect taxa, indicating one or more could provide consistent measures of trace metal bioavailability.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Metais/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise
15.
Environ Geochem Health ; 43(7): 2781-2798, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33576940

RESUMO

In this work, we report metals concentrations in 80 PM10 samples collected at four sites in the Mexico City Metropolitan Area (MCMA): Tlalnepantla (NE), Xalostoc (NE), Merced (C), and Pedregal (S), during the dry/cold season (October to January) for the 2004-2014 period. Mean PM10 mass concentration (66.1 µg m-3) significantly exceeds the annual mean air quality guidelines recommended by the World Health Organization. The statistical analysis of concentration data and meteorological parameters allows us to recognize the importance of wind intensity speed (Wsp) and wind direction conditions in the enrichment of PM concentrations. The proximity and magnitude of the emitting source is also relevant for PM concentration. Such conditions favored that higher metal concentration was recognized at the north of the studied area. By means principal component analysis (PCA) was difficult to identify the groups of metals associated with specific sources (anthropogenic and geogenic) given the high complexity of the study area and the long period of time evaluated. Metal concentration trend shows an important positive trend for Pt, V and Cr, while PM10, Ni, Cu, Ag and Sb show a trend of moderate increase. In contrast, Pb and Co registered a strong percentage reduction, while Hg, Mn, As and Cd show a slight reduction, probably resulting from the implementation of regulatory measures and influenced by urban changes associated at the north of the studied area. The results of this research provide information that should be considered for evaluating the impact of anthropogenic sources and applying regulatory measures to control emissions.


Assuntos
Poluentes Atmosféricos/análise , Metais Pesados/análise , Metais/análise , Material Particulado/análise , Poluição do Ar/análise , Cidades , Monitoramento Ambiental/métodos , México , Estações do Ano , Vento
16.
Artigo em Inglês | MEDLINE | ID: mdl-33535884

RESUMO

This paper was aimed at reviewing recent studies related with the impact on environment and human health of metals and PCDD/Fs near cement plants. It has been particularly focused on the impact of cement plants located in Catalonia, Spain, which have been monitored by our research for more than ten years. Environmental monitoring studies were performed under different cement plant conditions. While some of our studies examined temporal trends of the levels of the above indicated pollutants, the main goal of other surveys was to assess the impact of implementing alternative fuels in the facilities. Even one of the studies was performed before and after the cement plant temporally ceased its industrial activity. The impact of cement plants burning alternative fuels on the emissions of metals and PCDD/Fs elsewhere was also reviewed. Regarding the cement plants in Catalonia, no significant differences were found, neither in the long-term follow-up studies, nor when alternative fuels are used, nor when a cement plant temporally stopped its activity. These results are in agreement with those reported for several stack emissions of other cement plants working under different conditions. We conclude that emissions of metals and PCDD/Fs by cement plants working with the best available techniques (BAT), should not cause a significant negative impact neither on the surrounding environment, nor on the human health of the population living in the neighborhood.


Assuntos
Poluentes Atmosféricos/análise , Dibenzofuranos Policlorados/análise , Instalações Industriais e de Manufatura , Metais/análise , Dibenzodioxinas Policloradas/análise , Materiais de Construção , Fontes Geradoras de Energia , Humanos , Medição de Risco , Espanha
17.
Ecotoxicol Environ Saf ; 212: 111944, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33524910

RESUMO

Trace metals in street dust originate from many natural and anthropogenic sources and may directly or indirectly affect daily life and health. Here, the enrichment factor (EF), an efficient parameter to assess the contamination by trace metals, was evaluated and compared in four different zones of the urban area of Nanchang city during different seasons. Results showed that EFs of trace metals have regional seasonal variations. The EF range of Cr, Ni, Cu, Zn, As, Cd and Pb were found to be (0.76-16.38), (0.66-9.06), (1.09-169.58), (1.52-36.16), (0.44-7.17), (2.07-78.38), (0.95-20.94), respectively. These values indicate minimal to significant pollution. The EF values of Zn, Cd and Pb in street dust show very similar variations as their median and mean values of EF are higher in certain zones, and their seasonal variations are similar. The Ni and As results suggest that anthropogenic influences for these elements are not significant. The Ni may be influenced by land use type rather than point sources and As may be attributed to natural sources. The Principal Component Absolute Scores - Multivariate Linear Regression (PCAS-MLR) model was used to identify the types and contributions of trace metal sources. The main sources of trace metals in dust were found to be industrial discharges and traffic emissions. However, the percentages of their contributions have significant regional differences. The relationship between the EF of trace metals and the ecological risk index (ERI) was also investigated, and indicates that seriously polluted areas correspond to high ERI regions. The land use types and characteristics of the source jointly affects the relationship between EFs and ERI.


Assuntos
Poeira/análise , Monitoramento Ambiental , Metais/análise , China , Cidades , Poluentes Ambientais/análise , Poluição Ambiental/análise , Metais Pesados/análise , Medição de Risco , Estações do Ano , Oligoelementos/análise , Urbanização
18.
Wei Sheng Yan Jiu ; 50(1): 79-85, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33517966

RESUMO

OBJECTIVE: To detect the concentrations of ten metals and metalloid elements in the atmospheric PM_(2. 5) in Chengguan district and Xigu district of Lanzhou City from 2015 to 2018, and analyze the pollutant concentration and its change trend. METHODS: From 2015 to 2018, 662 samples of PM_(2. 5) were collected from Chengguan district and Xigu district of Lanzhou City. The concentrations of 10 kinds of metals and metalloid elements such as lead(Pb), arsenic(As), mercury(Hg), cadmium(Cd), chromium(Cr), antimony(Sb), manganese(Mn), nickel(Ni), selenium(Se), beryllium(Be) were detected, and the change trends of different monitoring points, years, seasons and months were analyzed. RESULTS: There was a significant difference in lead content between Chengguan District and Xigu District(χ~2=4. 80, P<0. 05), the median of Pb content in Chengguan and Xigu District was 45. 30 and 37. 20 ng/m~3, which was higher than that in Xigu District; the difference of Mn content in the two districts was statistically significant(χ~2=21. 28, P<0. 05), the median in two District was 32. 04 and 23. 37 ng/m~3, which was higher than that in Xigu District; the median of Be content in the two districts was statistically significant(χ~2=11. 57, P<0. 05), and the median of Be content in two districts was 0. 05 and 0. 07 ng/m~3, Xigu Distric was higher than Chengguan, there was no significant difference in other seven elements(P>0. 05). From 2015 to 2018, the element content of PM_(2. 5) in Chengguan District decreased by 47. 66% compared with 2015; Xigu District in 2018 decreased by 43. 79% compared with 2015; the higher element Pb, Mn and As in Chengguan District decreased by 52. 93%, 47. 00% and 49. 37% compared with 2015; in Xigu District, the content in 2018 decreased by 46. 87%, 47. 49% and 41. 98%compared with 2015, the contents of the remaining seven elements decreased in 2018 compared with those in 2015. There was no statistical significance(P>0. 05) in different seasons except for the difference of Ni content(P<0. 05), and the content of other elements showed a significant seasonal change: winter>spring>autumn> summer. The trend of monthly concentration change in the two regions was basically the same, the concentrations of Sb, As, Pb, Mn, Cd, Ni, Se, Hg and Cr were higher in November and February of next year. In Chengguan District and Xigu District, Ni content was higher in July and August, respectively;and Hg in Xigu District was higher in June, and Be was higher in less months, especially in February, October and December. CONCLUSION: From 2015 to 2018, the levels of 10 metals and metalloids element pollutants in PM_(2. 5) samples from Chengguan District and Xigu District of Lanzhou City showed a decreasing trend year by year, and had obvious seasonal changes.


Assuntos
Mercúrio , Metaloides , Metais Pesados , Cidades , Monitoramento Ambiental , Metais/análise , Metais Pesados/análise
19.
Environ Pollut ; 274: 116547, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33548672

RESUMO

Wetland snakes, as top predators, are becoming globally recognised as bioindicators of wetland contamination. Livers are the traditional test organ for contaminant exposure in organisms, but research is moving towards a preference for non-lethal tissue sampling. Snake scales can be used as an indicator of exposure, as many metals bind to the keratin. We used laser ablation with inductively coupled plasma-atomic emission spectroscopy and mass spectrometry (LA-ICP-MS) to quantify the concentrations of 19 metals and metalloids (collectively referred to 'metals' hereafter) in Western tiger snake (Notechis scutatus occidentalis) scales from four wetlands along an urban gradient, and compared them to concentrations measured in captive tiger snake scales. We conducted repeat measures to determine the concentration accuracy of each metal using LA-ICP-MS. Concentrations in wild Western tiger snake scales were significantly higher than in reference tiger snake scales for most metals analysed, suggesting accumulation from environmental exposure. We compared the scale concentrations to sediment concentrations of sampled wetlands, and found inter-site differences between mean concentrations of metals in scales parallel patterns recorded from sediment. Four metals (Mn, As, Se, Sb) had strong positive correlations with liver tissue contents suggesting scale concentrations can be used to infer internal concentrations. By screening for a larger suite of metals than we could using traditional digestive methods, we identified additional metals (Ti, V, Sr, Cs, Tl, Th, U) that may be accumulating to levels of concern in tiger snakes in Perth, Western Australia. This research has progressed the use of LA-ICP-MS for quantifying a suite of metals available in snake scales, and highlights the significance of using wetland snake scales as a non-lethal indicator of environmental contamination.


Assuntos
Monitoramento Ambiental , Metais , Animais , Metais/análise , Serpentes , Austrália Ocidental , Áreas Alagadas
20.
Food Chem ; 351: 129285, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33640775

RESUMO

Macro- and microelement determination in chocolate bars by microwave-induced plasma optical emission spectrometry (MIP OES) was evaluated after microwave-assisted sample digestion. Optimization of the sample digestion was carried out, and the recommended conditions were obtained at a temperature of 190 °C, with a digestion time of 40 min and in a mixture constituted by 2.3 mL of nitric acid, 1.0 mL of hydrogen peroxide and 4.7 mL of water. The method was applied in the analysis of chocolate bars, and the concentration ranges of the elements determined were (in mg kg-1): Ca (653-3096); Cr (<0.6-2.8); Cu (<0.16-19.5); Fe (<1.6-227); Mg (147-2775); K (3554-8573); Mn (<0.03-25.2); Na (45.6-1095); Ni (3.2-10.2); P (1111-22594) and Zn (4.8-33.3). The association of the proposed microwave-assisted acid digestion with the MIP OES technique was adequate for multi-element determination in chocolate bars for routine analysis.


Assuntos
Chocolate/análise , Micro-Ondas , Gases em Plasma/química , Espectrofotometria/métodos , Digestão , Temperatura Alta , Peróxido de Hidrogênio/química , Limite de Detecção , Metais/análise , Ácido Nítrico/química , Água/química
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