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1.
Braz. j. biol ; 84: e263534, 2024. tab
Artigo em Inglês | VETINDEX | ID: biblio-1384080

RESUMO

Honey is one of the best nutritious substances in the world, having different services in the body functions regulation. Ten elements (K, Na, Ca, Co, Cr, Mn, Mo, Ni, Pb, Se) from honey samples were analyzed from 80 different locations of Punjab and ten floras. The aim of the present study was to determine the quality and quantity of minerals and Physico-chemical analysis in honey. A flame photometer was used to measure the concentration of major minerals (K, Ca and Na). The concentration of micro minerals (Co, Cr, Mn, Mo, Ni, Pb and Se) was analyzed using Atomic Absorption Spectrometer. The concentration of macro-elements obtained was as follow (in ppm): K (166-1732), Na (107-418) and Ca (07-99), while the concentration of microelements (in ppm) Co (1-2), Cr (>1), Mn (<1), Mo (1.818), Ni (1.911), Pb (<1) and Se (1.968). The most abundant minerals were potassium, calcium and sodium, ranging between 396-810.5, 17.5-640.63 and 169.88-238.62 ppm, respectively. However, the trace mineral elements of honey were obtained in the order of decreasing Se > Co > Ni > Pb > Cr > Mo > Mn. The findings showed that all the heavy metals like Co, Cr, Ni and Pb were present in trace amounts and close to International Honey Quality Standard. The result of given honey samples represented highest value of moisture (31.23%), color (80 mm pfund), pH (8.23), acidity (72.02 meq/kg), electrical conductivity (0.85 ms/cm) and ash contents (0.83%).


O mel é uma das substâncias mais nutritivas do mundo, possuindo diversos serviços na regulação das funções do organismo. Dez elementos (K, Na, Ca, Co, Cr, Mn, Mo, Ni, Pb, Se) de amostras de mel foram analisados em 80 locais diferentes de Punjab e dez floras. O objetivo do presente estudo foi determinar a qualidade e quantidade de minerais e análises físico-químicas em mel. Um fotômetro de chama foi usado para medir a concentração dos principais minerais (K, Ca e Na). A concentração de microminerais (Co, Cr, Mn, Mo, Ni, Pb e Se) foi analisada utilizando espectrômetro de absorção atômica. A concentração de macroelementos obtida foi a seguinte (em ppm): K (166-1732), Na (107-418) e Ca (07-99), enquanto a concentração de microelementos (em ppm) Co (1-2), Cr (> 1), Mn (< 1), Mo (1,818), Ni (1,911), Pb (< 1) e Se (1,968). Os minerais mais abundantes foram potássio, cálcio e sódio, variando entre 396-810,5, 17,5-640,63 e 169,88-238,62 ppm, respectivamente. No entanto, os oligoelementos do mel foram obtidos na ordem decrescente Se > Co > Ni > Pb > Cr > Mo > Mn. Os resultados mostraram que todos os metais pesados ​​como Co, Cr, Ni e Pb estavam presentes em quantidades vestigiais e próximos ao Padrão Internacional de Qualidade do Mel. O resultado de determinadas amostras de mel representou o maior valor de umidade (31,23%), cor (80 mm pfund), pH (8,23), acidez (72,02 meq/kg), condutividade elétrica (0,85 ms/cm) e teor de cinzas (0,83%).


Assuntos
Metais Pesados/isolamento & purificação , Mel/análise , Minerais/isolamento & purificação , Índia
2.
Braz. j. biol ; 84: e258106, 2024. tab, mapas, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1374669

RESUMO

The antioxidant enzyme system is an important defense mechanism to cope with Reactive Oxygen Species (ROS) produced due to exposure to heavy metals. In the present study lead (Pb), chromium (Cr), arsenic (As), cadmium (Cd) and nickel (Ni) in water and the antioxidant activity of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) was investigated in three species (Metrocoris communis, Limnogonus fossarum fossarum, and Aquarius adelaidis) of water striders collected from the industrial triangle of Punjab, Pakistan. The results of present study revealed that Pb, Cr, As, Cd and Ni were according to the permissible amount of WHO. The antioxidant activity of SOD, CAT and POD was found significantly different among species against oxidative stress, but found the highest activity of determining parameters in A. adelaidis. This is one of the pioneer studies in Pakistan reporting the role of water striders as a bioindicator of heavy metals present in the water through antioxidants enzyme variations. The current results supported that variant level of antioxidant enzyme activities in different species of water strider were reflective of heavy metal pollution in the Industrial triangle of Punjab, Pakistan and will be a useful ecotoxicological tools to evaluate the detrimental effects of heavy metal pollutants in aquatic organisms.


O sistema enzimático antioxidante é um importante mecanismo de defesa para lidar com Espécies Reativas de Oxigênio (EROs) produzidas por causa da exposição a metais pesados. No presente estudo, o chumbo (Pb), o cromo (Cr), o arsênio (As), o cádmio (Cd), o níquel (Ni) em água e a atividade antioxidante da superóxido dismutase (SOD), catalase (CAT) e peroxidase (POD) foram investigados em três espécies (Metrocoris communis, Limnogonus fossarum fossarum e Aquarius adelaidis) de gafanhotos coletados no triângulo industrial de Punjab, Paquistão. Os resultados do presente estudo revelaram que Pb, Cr, As, Cd e Ni estavam de acordo com a quantidade permitida pela OMS. A atividade antioxidante de SOD, CAT e POD foi significativamente diferente entre as espécies diante do estresse oxidativo, mas encontrou a maior atividade de determinação de parâmetros em A. adelaidis. Este é um dos estudos pioneiros no Paquistão que relatam o papel dos water striders como bioindicador de metais pesados ​​presentes na água por meio de variações de enzimas antioxidantes. Os resultados atuais indicaram que o nível variante de atividades de enzimas antioxidantes em diferentes espécies de water striders refletiu a poluição por metais pesados ​​no triângulo industrial de Punjab, Paquistão, e será uma ferramenta ecotoxicológica útil para avaliar os efeitos prejudiciais de poluentes de metais pesados ​​em organismos aquáticos.


Assuntos
Animais , Poluição da Água , Metais Pesados , Biomarcadores Ambientais , Organismos Aquáticos , Gafanhotos , Antioxidantes
3.
Braz. j. biol ; 84: e256071, 2024. tab, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1374665

RESUMO

The present study was conducted to measured heavy metals in cyprinid fishes in rivers of District Khuzdar Balochistan, Pakistan. In the present study, 25 fish samples were collected that belonged to 8 order of 13 families, The Cyprinidae family had the largest number of eight fish species. Present study is focused on Heavy metals in cyprinid fishes. Heavy metals accumulation like Zinc, Manganese, Copper, and Nickel was evaluated in water and various organs of fishes. Atomic Absorption Spectroscopy was used for the identification of these heavy metals in fish species and water bodies. The average concentration (mg/L) of Zn 0.26-0.41, Mn 0.030- 0.073, Cu 0.017—0.080 and NI 0.14-0.79 were observed in water. The Concentration (mg/L), of Zn Conc 0.383-.028 Mn Conc .073- .030 Cu Conc 080-.017 NI Conc .79-.14. The concentration of heavy metals was found both similar and varied simultaneously across the whole research area. Zinc concentration was reported highest, whereas Copper was at the lowest concentration in all fish species .The concentration of heavy metals, in all the fish species under this study, was above the threshold of WHO limits.


O presente estudo foi realizado para medir metais pesados em peixes ciprinídeos em rios do Distrito Khuzdar Balochistan, Paquistão. No presente estudo, foram coletadas 25 amostras de peixes pertencentes a 8 ordens de 13 famílias. A família Cyprinidae apresentou o maior número de oito espécies de peixes. O presente estudo está focado em metais pesados em peixes ciprinídeos. O acúmulo de metais pesados como zinco, manganês, cobre e níquel foi avaliado na água e em vários órgãos dos peixes. A Espectroscopia de Absorção Atômica foi utilizada para a identificação desses metais pesados em espécies de peixes e corpos d'água. A concentração em água ((mg/L),) Zn Conc. 0,383-.028 Mn Conc. .073- .030 Cu Conc. 080-.017 NI Conc. 0,79-.14. A concentração de metais pesados foi considerada semelhante e variou simultaneamente em toda a área de pesquisa. A concentração de zinco foi relatada mais alta, enquanto o cobre estava na concentração mais baixa em todas as espécies de peixes. A concentração de metais pesados, em todas as espécies de peixes neste estudo, estava acima do limite dos limites da Organização Mundial da Saúde (OMS).


Assuntos
Animais , Poluição da Água , Metais Pesados , Rios , Peixes , Paquistão
4.
Braz. j. biol ; 84: e260355, 2024. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1374663

RESUMO

Bioaccumulation of toxic heavy metals in the human body can give rise to adverse health effects, the severity of which depends upon their dosage and duration of exposure. In this study, yearlings of two different species of edible fish, i.e., Tor putitora (Mahseer) and Ctenopharyngodon Idella (grass carp), were exposed to different concentrations of lead nitrate in a controlled environment of aquarium for three different lengths of duration (14, 28, and 60 days). The bioaccumulation of lead in different organs, including gills, skin, muscles, liver, intestine, and swim bladder of the fish, was assessed using atomic absorption spectrometry. Generally, the highest lead concentration was observed in the gills and lowest in the muscles for both species at each experimental dosage and duration. In 14-days exposure, the relative pattern of bioaccumulation in different organs was observed as gill > liver > skin > intestine > swim bladder > muscle for both fish species. Similarly, the pattern of bioaccumulation observed in 28-days exposure was as: gill > liver > intestine > skin > swim bladder > muscle in both species. Whereas, pattern in 60-days exposure was observed as gill > liver > intestine > swim bladder > muscle > skin. The data shows that grass carp had stored higher concentrations of lead than Mahseer, which may be attributed to the fact that they are omnivorous. Furthermore, the lowest bioaccumulation was recorded in the muscles until the 56th day of the exposure, after which the concentration steadily increased in the muscles. The observed pattern highlights the importance of exposure's duration to lead; chronic exposure could result in its bioaccumulation at toxic concentrations in the muscles, which is particularly of concern because the fish muscles are heavily consumed as food worldwide.


A bioacumulação de metais pesados tóxicos no corpo humano pode causar efeitos adversos à saúde, cuja gravidade depende de sua dosagem e duração da exposição. Neste estudo, filhotes de duas espécies diferentes de peixes comestíveis, ou seja, Tor putitora (Mahseer) e Ctenopharyngodon idella (carpa-capim), foram expostos a diferentes concentrações de nitrato de chumbo em um ambiente controlado de aquário por três diferentes períodos de duração (14, 28 e 60 dias). A bioacumulação de chumbo em diferentes órgãos, incluindo brânquias, pele, músculos, fígado, intestino e bexiga natatória dos peixes, foi avaliada por espectrometria de absorção atômica. Geralmente, a maior concentração de chumbo foi observada nas brânquias e a menor nos músculos para ambas as espécies em cada dosagem e duração experimental. Na exposição de 14 dias, o padrão relativo de bioacumulação em diferentes órgãos foi observado como brânquia > fígado > pele > intestino > bexiga natatória > músculo para ambas as espécies de peixes. Da mesma forma, o padrão de bioacumulação observado em 28 dias de exposição foi: brânquia > fígado > intestino > pele > bexiga natatória > músculo em ambas as espécies. Já o padrão de exposição de 60 dias foi observado como brânquia > fígado > intestino > bexiga natatória > músculo > pele. Os dados mostram que a carpa-capim armazenou maiores concentrações de chumbo do que a Mahseer, o que pode ser atribuído ao fato de serem onívoras. Além disso, a menor bioacumulação foi registrada nos músculos até o 56º dia de exposição, após o que a concentração aumentou de forma constante nos músculos. O padrão observado destaca a importância da duração da exposição ao chumbo; a exposição crônica pode resultar em sua bioacumulação em concentrações tóxicas nos músculos, o que é particularmente preocupante porque os músculos dos peixes são muito consumidos como alimento em todo o mundo.


Assuntos
Animais , Carpas , Saúde Pública , Metais Pesados , Peixes , Bioacumulação
5.
Braz. j. biol ; 84: e252143, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364526

RESUMO

Cadmium (Cd) is one of non-essential heavy metals which is released into environment naturally or anthropogenically. It is highly persistent toxic metals that are exceptionally distressing industrial and agriculture activities by contaminating soil, water and food. Its long-duration endurance in soil and water results in accumulation and uptake into plants, leading to the food chain. This becomes a serious global problem threatening humans and animals as food chain components. Living organisms, especially humans, are exposed to Cd through plants as one of the main vegetative food sources. This review paper is concentrated on the symptoms of the plants affected by Cd toxicity. The absorption of Cd triggers several seen and unseen symptoms by polluted plants such as stunted growth, chlorosis, necrosis and wilting. Apart from that, factors that affect the uptake and translocation of Cd in plants are elaborated to understand the mechanism that contributes to its accumulation. By insight of Cd accumulation, this review also discussed the phytoremediation techniques-phytoextraction, phytostimulation, phytostabilization, phytovolatization and rhizofiltration in bioremediating the Cd.


O cádmio (Cd) é um dos metais pesados ​​não essenciais que é liberado no meio ambiente de forma natural ou antropogênica. São metais tóxicos altamente persistentes que prejudicam excepcionalmente as atividades industriais e agrícolas, contaminando o solo, a água e os alimentos. Sua resistência de longa duração no solo e na água resulta em acúmulo e absorção pelas plantas, levando à cadeia alimentar. Isso se torna um sério problema global que ameaça humanos e animais como componentes da cadeia alimentar. Os organismos vivos, principalmente os humanos, são expostos ao Cd através das plantas como uma das principais fontes de alimento vegetativo. Este artigo de revisão concentra-se nos sintomas das plantas afetadas pela toxicidade do Cd. A absorção de Cd desencadeia vários sintomas visíveis e invisíveis por plantas poluídas, como crescimento atrofiado, clorose, necrose e murcha. Além disso, são elaborados fatores que afetam a absorção e translocação de Cd nas plantas para entender o mecanismo que contribui para o seu acúmulo. A partir do conhecimento do acúmulo de Cd, esta revisão também discutiu as técnicas de fitorremediação - fitoextração, fitoestimulação, fitoestabilização, fitovolatização e rizofiltração na biorremediação do Cd.


Assuntos
Plantas/toxicidade , Cádmio , Metais Pesados , Alimentos/toxicidade
6.
Braz. j. biol ; 84: e248946, 2024. tab, mapas, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364502

RESUMO

Environmental pollutants may often alter the genetic components of natural populations. In this study, heavy metals and genetic diversity in land snail (Achatina achatina) from three populations of south-western Nigeria were investigated, using the Atomic Absorption Spectrometry and DNA Sequencing technology respectively. Metal analysis revealed that the snails accumulated lead (Pb) and nickel (Ni) in high concentrations in two of the three states, while cadmium (Cd) was the least detected. Editing and alignment of the sequences of all snail accessions generated a range of 384bp to 419 bp. Analysis of Molecular Variance (AMOVA) in all 18 accessions was low at only 16%. The query coverage (QC) ranged between 96% and 100%, with 14 (77.8%) of the 18 accessions showing 100% identity. Pairwise comparison of the accessions studied also showed a high genetic similarity. The unweighted pair group method with arithmetic mean (UPGMA) generated two main clusters. Cluster I was unique and contain one sample (AaOy06) while the other cluster are very closely related and can be further sub-divided into sub-clusters. The similarity index of between the clusters is 0.5357. The close similarity among the accessions may be due to the geographical proximity of the three states. The uniqueness of accession AaOy06 in comparison to other accessions might be due to the negative influence of heavy metal, particularly lead. The determination of evolutionary relationships among snail populations may be useful towards the breeding efforts of the species in Nigeria.


Os poluentes ambientais podem frequentemente alterar os componentes genéticos das populações naturais. Neste estudo, metais pesados e diversidade genética em caramujos terrestres (Achatina achatina) de três populações do sudoeste da Nigéria foram investigados, usando a tecnologia de espectrometria de absorção atômica e sequenciamento de DNA, respectivamente. A análise dos metais revelou que os caramujos acumularam chumbo (Pb) e níquel (Ni) em altas concentrações em dois dos três estados, enquanto o cádmio (Cd) foi o menos detectado. A edição e o alinhamento das sequências de todos os acessos de caramujos geraram uma faixa de 384pb a 419pb. A análise de variância molecular (AMOVA) em todos os 18 acessos foi baixa em apenas 16%. A cobertura da consulta (QC) variou entre 96% e 100%, com 14 (77,8%) dos 18 acessos apresentando 100% de identidade. A comparação pareada dos acessos estudados também mostrou alta similaridade genética. O método de grupo de pares não ponderados com média aritmética (UPGMA) gerou dois clusters principais. O cluster I era único e contém uma amostra (AaOy06), enquanto o outro cluster está intimamente relacionado e pode ser subdividido em subclusters. O índice de similaridade entre os clusters é 0,5357. A grande semelhança entre os acessos pode ser devido à proximidade geográfica dos três estados. A singularidade do acesso AaOy06 em comparação com outros acessos pode ser devido à influência negativa de metais pesados, particularmente chumbo. A determinação das relações evolutivas entre as populações de caramujos pode ser útil para os esforços de reprodução da espécie na Nigéria.


Assuntos
Animais , Caramujos , Variação Genética , Metais Pesados , Poluentes Ambientais
7.
Food Chem ; 398: 133866, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35964561

RESUMO

Seaweeds are a rich source of nutritional and functional compounds, but they also accumulate heavy metals. Here, the chemical composition (crude protein, total lipids, Nitrogen Free Extract and fiber) and the presence of minerals (Na, K, Ca, Mg, P, Fe, Mn, Cu, Zn, Mo, Se) and unwanted elements (As, Cd, Hg, Pb, Ni, Cr, Al) were determined in eleven seaweeds from Chile. Depending on the species, a good contribution to the Recommended Dietary Allowance for K, Ca, Mg, Fe, Mn and Se was observed, and low Na/K ratios (<1.0) as well. The health risk assessment indicated low hazard due to intake of seaweed meal. The mean values of As, Hg, and Pb were below the maximum limits set for food supplements and feed ingredients. The seaweeds studied have a suitable chemical composition for their uses as food and feed ingredients, although Cd levels should be monitoring especially in brown seaweeds.


Assuntos
Mercúrio , Metais Pesados , Alga Marinha , Cádmio/metabolismo , Chile , Monitoramento Ambiental , Chumbo/metabolismo , Mercúrio/metabolismo , Metais Pesados/análise , Alga Marinha/química
8.
J Hazard Mater ; 443(Pt B): 130283, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36370480

RESUMO

Metal(loid)s contamination poses a serious threat to ecosystem biosafety and human health. Phytoremediation is a cost-effective and eco-friendly technology with good public acceptance, although the process does require a significant amount of time for success. To enhance the phytoremediation efficiency, numerous approaches have been explored, including soil amendments application with chelators to facilitate remediation. Sulfur (S), a macronutrient for plant growth, plays vital roles in several metabolic pathways that can actively affect metal(loid)s phytoextraction, as well as attenuate metal(loid) toxicity. In this review, different forms of S-amendments (fertilizers) on uptake and translocation in plants upon exposure to various metal(loid) are evaluated. Possible mechanisms for S application alleviating metal(loid) toxicity are documented at the physiological, biochemical and molecular levels. Furthermore, this review highlights the crosstalk between S-assimilation and other biomolecules, such as phytohormones, polyamines and nitric oxide, which are also important for metal(loid) stress tolerance. Given the effectiveness and potential of S amendments on phytoremediation, future studies should focus on optimizing phytoremediation efficiency in long-term field studies and on investigating the appropriate S dose to maximize the food safety and ecosystem health.


Assuntos
Metais Pesados , Poluentes do Solo , Humanos , Biodegradação Ambiental , Poluentes do Solo/análise , Metais Pesados/análise , Biofortificação , Ecossistema , Plantas/metabolismo , Enxofre
9.
Sci Total Environ ; 858(Pt 2): 159662, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36302423

RESUMO

This study was conducted to address the changes in the surface distribution of trace metals (cobalt, copper, iron, cadmium, nickel, zinc, lead and molybdenum) as they are advected from the Gulf of Cadiz to the Alboran Sea, through the Strait of Gibraltar (south Iberian Peninsula), regions of great ecosystemic importance. Trace metals concentrations were measured in samples collected during two oceanographic cruises, together with the main factors affecting their spatial distribution and temporal variability (i.e., wind and surface currents). Several rivers, the main source of trace metals in this region, flow into the Gulf of Cadiz which is connected with the Alboran Sea through the Strait of Gibraltar by the general circulation pattern. The surface circulation pattern leads to an offshore-eastward gradient that is highly influenced by wind variability. An increase in vertical turbulence induced by the winds or the tidal cycle causes the dilution of trace metals' concentration by mixing rich-metal superficial waters with poor-metal subsurface waters. Additionally, along the eastward displacement of surface waters, several water retention zones have been described (Trafalgar, Camarinal, the Coastal Cyclonic Gyre) that imply an increase in trace metals concentration close to the coast. In addition, our results suggest that the coastal edges of the Strait of Gibraltar also act as a source of certain metals to the Alboran Sea, probably due to the industries in the proximity areas.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Oligoelementos/análise , Metais/análise , Cádmio/análise , Metais Pesados/análise
10.
Sci Total Environ ; 858(Pt 2): 159750, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36309279

RESUMO

Heavy metal pollution by accelerating urbanization is an emerging socio-environmental issue that poses a potential risk to human health and the environment. In this scenario, street dust is a primary source of contaminants. Here, the metal concentrations in street dust of one of the biggest Brazilian cities were assessed aiming to identify and quantify the sources of contamination. The metal bioaccessibility and estimated probabilistic (non)-carcinogenic risks to humans were also evaluated. Thirty-six dust samples were collected in the metropolitan region of Recife. Results showed that the traffic governed the distribution and accumulation of metals in street dust. Emissions from vehicles were the primary source (> 70 %) of heavy metals, except for Cd, which had a mixed origin (natural, traffic, and industrial). Moderate to heavy dust contamination by Ba, Cu, Mn, Pb, and Zn were found, with a very high potential ecological risk. The main exposure route depended on the metal. Barium, Cu, and Pb had ingestion rather than dermal contact as the main route of exposure, while inhalation and dermal contact posed the main risks to Mn and Cr, respectively. The risk for children was higher than for adults. The probabilities of unacceptable carcinogenic risk scenarios (TCRI >10-6) for children and adults were 27 and 4 %, respectively, with Cr being the most concerning metal for the health of the urban population.


Assuntos
Poeira , Metais Pesados , Adulto , Criança , Humanos , Poeira/análise , Brasil , Chumbo , Monitoramento Ambiental/métodos , Metais Pesados/análise , Cidades , Medição de Risco/métodos , Carcinógenos/análise , China
11.
Sci Total Environ ; 858(Pt 2): 159819, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36334671

RESUMO

Unintentional ingestion of metal-contaminated soils may pose a great threat to human health. To accurately evaluate the health risks of heavy metal(loid)s in soils, their bioaccessibility has been widely determined by in vitro assays and increasingly employed to optimize the assessment parameters. Given that, using meta-analysis, we analyzed the literature on farmland heavy metal(loid)s (As, Cd, Cr, Cu, Hg, Pb, Ni, and Zn) in Chinese main grain production regions, and collected their total and bioaccessibility data to accurately assess their human health risks. Monte Carlo simulation was used to reduce the uncertainty in metal concentration, intake rate, toxicity coefficient, and body weight. We found that the mean concentration (0.47 mg/kg) and geological accumulation index (Igeo, 0-5.24) of Cd were the priority position of controlling metals. Moreover, children are more vulnerable to carcinogenic risks than adults. Soil mineralogy, physicochemical properties, Fe, and the types of in vitro assays are the influencing factors of bioaccessibility discrepancy. Furthermore, appropriate bioaccessibility determination methods can be adapted according to the differences in ecological receptors for the risk assessment, like developing a "personalized assessment" scheme for polluted farmland soil management. Collectively, bioaccessibility-based models may provide an accurate and effective approach to human health risk assessment.


Assuntos
Metais Pesados , Poluentes do Solo , Criança , Adulto , Humanos , Solo/química , Poluentes do Solo/análise , Cádmio/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , China , Medição de Risco/métodos , Grão Comestível/química
12.
Sci Total Environ ; 858(Pt 2): 159895, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336052

RESUMO

Si/Al-based adsorbents are effective adsorbents for capturing heavy metals in incineration flue gases at high temperatures in the furnace. In this work, the adsorption characteristics and adsorption mechanisms of Si/Al-based adsorbents for lead and cadmium vapors were studied using a combination of experimental and density functional theory (DFT) calculations. The trapping performance of a series of Si/Al-based adsorbents for Pb and Cd vapors was investigated using a self-designed gas-solid two-phase rapid adsorption experimental system. The results showed that kaolinite and montmorillonite exhibited better heavy metal adsorption capacity than SiO2 and Al2O3, and were significantly stronger for Pb than for Cd. Chemisorption dominated the capture of Pb/Cd by Si/Al-based adsorbents at high temperatures. The results of DFT calculations indicated that the chemisorption mechanisms dominated the adsorption of Pb and Cd species on the metakaolinite (001) surface, and the adsorption energy of Pb species on the metakaolinite surface was greater than that of Cd species. The exposed O atoms and unsaturated Al atoms of metakaolinite (001) surface were effective adsorption active sites for heavy metals and their chlorides. In the adsorption reaction, the binding of Pb/Cd atoms and surface exposed O sites, as well as the strong interaction between Cl and unsaturated Al atoms, were responsible for the capture of Pb and Cd chlorides by metakaolinite.


Assuntos
Incineração , Metais Pesados , Cádmio/química , Adsorção , Chumbo , Dióxido de Silício , Cloretos , Gases/química , Metais Pesados/química , Modelos Teóricos
13.
Environ Pollut ; 316(Pt 2): 120596, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36343852

RESUMO

The health risk of soil heavy metals pollution has been gaining increasing public concern. However, many countries have not set their own health risk assessment (HRA) framework and most of the existing studies directly referred to the USEPA risk assessment model and parameters. For those countries that do not propose an original HRA framework, the experience of developed countries is crucial for advancing their own HRA system. This study systematically reviewed the development of HRA framework in some representative developed countries. The theoretical basis, conceptual model, progress, and challenges of HRA researches concerning soil heavy metals pollution were summarized. By recalling and comparing the health risk-related laws and guidance in the USA, UK, and Japan, results showed that the construction of HRA framework varied between these countries, but HRA has become the main method for deriving their soil environmental criteria. We further summarized the evaluation scales, land use types, exposure pathways, and sensitive receptors of HRA studies, and highlighted the key parameters affecting health risk outputs. There has been a shift toward the incorporation of probabilistic modeling, metals bioavailability, and sources emission characteristics into recent HRA studies. Nonetheless, challenges remained on how to minimize the uncertainty of generating probability distribution and detecting metal bioavailability. To facilitate the development of HRA framework, it was advised that developing countries should strengthen the theoretical researches of health risk and localization researches of exposure factors. Future directions are suggested to tend to: 1) promote sensitive analysis to quantify the impact of distribution assumptions on health risk outputs, 2) derive reasonable risk threshold and consistent evaluation protocol for bioavailability-based health risk assessment method, and 3) strive to explore the combined health effect of exposure to heavy metals in soil through source-media-receptor integrated studies.


Assuntos
Metais Pesados , Poluentes do Solo , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Metais Pesados/análise , Solo , Medição de Risco , China
14.
Chemosphere ; 312(Pt 2): 137193, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36370766

RESUMO

Clean water shortages require the reuse of wastewater. The presence of organic substances such as humic acids in wastewater makes the water treatment process more difficult. Humic acids can significantly affect the removal of heavy metals and other such toxins. Humic acids is formed by the decomposition and transformation of animal and plant remains by microorganisms, and naturally exists in soil and water. It is necessary to degrade and remove humic acids from wastewater. As it seriously human health, effective technologies for removing humic acids from wastewater have attracted great interest over the past decades. This study compared existing techniques for removing humic acids from wastewater, as well as their limitations. Physicochemical treatments including filtration and oxidation are basic and key approaches to removing humic acids. Biological treatments including enzyme and fungi-mediated humic acids degradation are economically feasible but require some scalability. In conclusion, the integrated treatment processes are more significant options for the effective removal of humic acids from wastewater. In addition, humic acids have rich utilization values. It can improve the soil, increase crop yields, and promote the removal of pollutants.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Purificação da Água , Humanos , Substâncias Húmicas/análise , Águas Residuárias , Purificação da Água/métodos , Solo/química , Poluentes Químicos da Água/metabolismo
15.
Environ Pollut ; 316(Pt 2): 120622, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370975

RESUMO

The metal-organic frameworks/cotton fabric composites (MOFs/CFCs) have emerged as a new type of prospective materials for environmental cleanup, due to their convenient recyclability and high removal efficiency towards hazardous pollutants. However, their practical applications are limited by complicated synthetic conditions, insufficient interface bonding and poor adsorption capacity. Herein, for the first time, a robust ethylenediaminetetraacetic acid (EDTA)-functionalized MOFs/CFC is prepared based on UiO-66-NH2 crystals by using EDTA dianhydride as the cross-linking agent, and applied for simultaneous removal of heavy metals and dyes, as well as degradation of chemical warfare agents. The as-prepared EDTA-UiO-66-NH2/CFC shows extraordinary monocomponent adsorption performance with maximum adsorption capacity of 158.7, 126.2, 131.5, 117.4 and 104.5 mg/g for Cd(II), Cu(II), methylene blue, crystal violet and safranin O, respectively. Interestingly, in metal-dyes binary system, the uptake of Cu(II) by EDTA-UiO-66-NH2/CFC increases significantly when co-existing high concentration of dyes. The results indicate that the synergistic and simultaneous removal of both dyes and metal from complex systems can be realized by EDTA-UiO-66-NH2/CFC via multiple mechanisms. The EDTA-UiO-66-NH2/CFC also exhibits an outstanding catalytic performance for degrading dimethyl 4-nitrophenylphosphate. Besides, it can be reused for several times without obvious decrease of its adsorption and catalysis efficiencies. More impressively, the cross-linking reaction approach can not only anchor UiO-66-NH2 crystals firmly onto cotton fabric, but also facilitate in-situ formation of abundant adsorption sties on the adsorbent surface. Therefore, this work offers a simple and versatile synthetic strategy to develop high-performance environmental material for multiple pollutants remediation.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Corantes , Ácido Edético , Organofosfatos , Poluentes Químicos da Água/química , Adsorção
16.
Environ Pollut ; 316(Pt 2): 120629, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370976

RESUMO

This study deals with the potential release of metal/loids from sulfide mine wastes upon weathering and the health risks associated with their accidental ingestion. To address this, a complete chemical and mineralogical characterization of a variety of sulfide mine wastes was performed alongside a determination of metal/loid bioaccessibility through leaching tests simulating human digestive and lung fluids. The mine wastes consisted predominantly of Fe (35-55% of Fe2O3) and exhibited high concentrations of trace metalloids such as As (382-4310 mg/kg), Pb (205-15,974 mg/kg), Cu (78-1083 mg/kg), Zn (274-1863 mg/kg), or Sb (520-1816 mg/kg). Most wastes with high concentrations of soluble compounds are considered hazardous according to the European regulations due to the exceedance of threshold values for As, Pb, Cr, Cu, Sb, sulfates, and Zn determined by standardized tests. In general terms, the absorption of waste-hosted metals through both digestive and respiratory routes was low compared to the total metal contents of the wastes, with values below 8% of the total concentration in wastes for most metal/loids including Cu, Zn, As, Cd, Tl, or U. However, some metals exhibited a significantly higher absorption potential, especially through the respiratory route, reaching values of up to 17% for Cr and 75% for Pb, highlighting the strong bioaccessibility of Pb in certain sulfide wastes. Despite the high metal/loid concentrations observed in the studied wastes, a health risk assessment indicated that some non-carcinogenic effects could be observed in children only following the accidental digestion of Pb.


Assuntos
Metaloides , Metais Pesados , Poluentes do Solo , Criança , Humanos , Poluentes do Solo/análise , Chumbo , Monitoramento Ambiental , Mineração , Metaloides/análise , Sulfetos , Metais Pesados/análise , Medição de Risco
17.
Sci Total Environ ; 858(Pt 1): 159504, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36265645

RESUMO

The behavior and stability of trace metals in sediment are important to the ecology of rivers. Deteriorated water quality from domestic wastewater discharge has been studied extensively, but the effect of domestic wastewater on trace metals in sediment is poorly understood. To investigate this, we simulated the water quality degradation process through leaching experiments using domestic wastewater as the leaching solution. The results indicated that domestic wastewater does not negatively influence the stability and fractionation of trace metals in this experimental model, the existence of phosphate was the pacing factor for this phenomenon. Single-factor control treatment groups showed that a leaching solution with pH < 6, NaCl, NH4Cl, NaNO3, and humic acid promoted the dissolution of trace metals from sediment, whereas NaH2PO4 inhibited this process and increased their stability in sediment. The response of trace metals behavior to NaCl, NH4Cl, and extreme pH levels was more sensitive than NaNO3 and HA. Chloride ions can form relatively stable compounds with trace metals, reducing the activity of trace metals in the solution and promoting the release of trace metals from sediment, but it has positive effect on Pb and Zn stability and negative effect on Cu. Extreme pH conditions (pH > 10) and higher concentrations of leaching solutions (NaCl, NH4Cl, NaNO3, and HA) led to an increase in the Cu leaching concentration from sediment and the transformation to unstable fractions, while the impact on the stability of Zn and Pb was beneficial or had little effect. These experiment groups indicated that phosphate is beneficial to the stability of trace metals even at the condition of water degradation and can decrease the ecological risk caused by trace metals.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Sedimentos Geológicos/química , Metais Pesados/análise , Qualidade da Água , Águas Residuárias , Cloreto de Sódio , Chumbo , Oligoelementos/análise , Fosfatos , Poluentes Químicos da Água/análise , Monitoramento Ambiental
18.
Sci Total Environ ; 858(Pt 1): 159672, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306838

RESUMO

Graphene oxide is a two-dimensional carbon nanomaterial and has gained huge popularity over the last decade. Because, the graphene oxide can be dispersed in water easily and it is one of the most researched two-dimensional materials in the current time. The extraordinary properties shown by graphene oxide (GO) are due to its unique chemical structure; includes various hydrophilic functional groups containing oxygen such as carboxyl, hydroxyl, carbonyl and tiny sp2 carbon domains surrounded by sp3 domains. These groups are very peculiar for various applications as they allow covalent functionalisation with a plethora of compounds. Large surface area, intrinsic fluorescence, excellent surface functionality, amphiphilicity, improved conductivity, high adsorption capacity and superior biocompatibility are some of the chemical properties have drawn research from various fields. Graphene oxide has various interactions such as coordination, chelation, hydrogen bonding, electrostatic interaction, hydrophobic effects, π-π interaction, acid base interaction etc., with various metal ions. This review is focused on the removal of metals and metal ions due to their interactions mentioned above. Further, potential of composites of graphene oxide in the removal of metal and metal ions is also discussed. Further, the current challenges in this field at industrial-scale are also discussed.


Assuntos
Grafite , Metais Pesados , Poluentes Químicos da Água , Metais Pesados/química , Poluentes Químicos da Água/análise , Grafite/química , Adsorção , Íons , Carbono
19.
Sci Total Environ ; 858(Pt 1): 159799, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36309257

RESUMO

Direct discharge of chromium-containing waste water and improper disposal of waste residues in industrial sites may lead to the vertical migration of metals into aquifers, posing serious threat to soil-groundwater system. The heterogeneity in soil profile further aggravates the complexity and unpredictability of this transport process. However, topsoil was the main focus of most studies. Herein, the vertical transport and transformation of Cr in soils at different depths in three industrial sites (i.e., Shijiazhuang, Zhuzhou, and Guangzhou) were investigated to delineate Cr transport and retention characteristics under complex conditions. Regional and vertical differences in soil properties led to the specificity in Cr migration behaviors among these three sites. Correlation analysis showed that soil pH (r = -0.909, p < 0.05) and Fe content (r = 0.949, p < 0.01) were the major controlling factors of Cr(VI) migration and transformation in aquifers. Furthermore, the soil of Zhuzhou site showed the maximum adsorption capacity for Cr(VI) (0.225 mol/kg), and the strongest reduction ability of Cr(VI) was observed in the Guangzhou soil. Results of model-based long-term forecast indicated that the Cr(III) concentration in the liquid phase of Guangzhou subsoil could reach 0.08 mol/m3 within 20 years. Heavier rainfall condition exacerbated the contamination due to an increased pollutant flux and enhanced convection. Specially, Cr was fixed in the topsoil of Zhuzhou site with the formation of PbCrO4 and presented least vertical migration risk. The conclusions above can provide scientific theoretical guidance for heavy metal pollution prevention and control in industrial contaminated regions.


Assuntos
Metais Pesados , Poluentes do Solo , Solo/química , Poluentes do Solo/análise , Cromo/análise , Metais Pesados/análise
20.
Sci Total Environ ; 858(Pt 1): 159732, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36309268

RESUMO

Anthropogenic activities such as mining, smelting industries, and the application of pesticides in agriculture might result in contamination of multiple heavy metals in the environment. Heavy metal contamination of sediment is a serious environmental problem, and thus the remediation of contaminated sediment is a worldwide challenge. Several strategies have been developed for the remediation of contaminated sediment, however the ecological risk and ecotoxicity of the restored sediment have rarely been evaluated. We assessed whether river sediment highly contaminated with heavy metals could be restored using microbial bioleaching followed by evaluating the residual toxicity and ecological risk of the microbially remediated sediment. Sequential extraction revealed that the bioavailable levels of Cu, Ni, and Zn in the contaminated sediment exceeded sediment quality guideline (SQG) thresholds. It was consequently found that acidophilic sulfur-oxidizing Acidicaldus sp. SV5 effectively bioleached Cu, Ni, and Zn from the contaminated sediment, reducing the bioavailable fraction of these elements below SQG thresholds. The ecological risk assessment indicated that SV5-driven remediation significantly reduced the potential ecological risk of the contaminated sediment. The residual ecotoxicity of the microbially remediated sediment was also tested with the soil nematode Caenorhabditis elegans. There was a significant decrease in the body burden of Cu, Ni, and Zn in C. elegans and a reduction in the toxicological effect on survival, growth, and reproduction in the microbially remediated sediment. Our study suggests that a combination of chemical analysis, chemical-based ecological risk assessment, and ecotoxicity tests would be helpful for the development of efficient and eco-friendly strategies for the restoration of contaminated sediment, which could be incorporated into sediment quality management practices.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Animais , Rios , Sedimentos Geológicos , Caenorhabditis elegans , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Medição de Risco , Monitoramento Ambiental , China
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