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1.
Braz. j. biol ; 83: e249641, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1339363

RESUMEN

Abstract Estuaries receive daily inputs of chemical elements which can impact the quality of water and sediment, as well as the health of biota. In addition to the sediment, bivalve mollusks have been used in the chemical monitoring of these systems. This study investigated the presence and contents of As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in superficial sediment and in bivalves (Crassostrea gasar, C. rhizophorae and Mytella guyanensis) from estuaries in the south / extreme south of Bahia State, northeast Brazil. The samples were evaluated with inductively coupled plasma optical emission spectrometry (ICP-OES, Varian 710). Except for Cd, all other elements were found in the samples, being that Co was exclusive in the sediment. The estuaries equivalent to sampling stations #1 - Valença, #2 - Taperoá, #3 - Ilhéus and #4 - Belmonte showed levels of metals compatibles with those established by the Brazilian legislation, however, the #5 - Santa Cruz Cabrália, in addition to the presence of As, presented a high level of Pb and Cu in C. gasar, which was attributed to the impacts of nautical activities in that locality.


Resumo Estuários recebem entradas diárias de elementos químicos, que podem impactar a qualidade de água e do sedimento, assim como a saúde da biota. Além do sedimento, moluscos bivalves têm sido utilizados no monitoramento químico desses sistemas. Neste estudo investigou-se a presença e os teores de As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb e Zn no sedimento superficial e em bivalves (Crassostrea gasar, C. rhizophorae e Mytella guyanensis) de estuários do sul / extremo sul do estado da Bahia, Nordeste do Brasil. As amostras foram avaliadas por espectrometria de emissão óptica de plasma indutivamente acoplado (ICP-OES, Varian 710). Exceto Cd, todos os demais elementos foram encontrados nas amostras, sendo que Co foi exclusivo no sedimento. Os estuários equivalentes às estações amostrais #1 - Valença, #2 - Taperoá, #3 - Ilhéus e #4 - Belmonte mostraram níveis de metais compatíveis com os estabelecidos pela legislação brasileira, porém, a #5 - Santa Cruz Cabrália, além da presença de As, apresentou alto nível de Pb e de Cu em C. gasar, o que foi atribuído aos impactos por atividades náuticas nesse local.


Asunto(s)
Animales , Contaminantes Químicos del Agua/análisis , Bivalvos , Metales Pesados/análisis , Brasil , Monitoreo del Ambiente , Estuarios , Sedimentos Geológicos
2.
Braz. j. biol ; 83: e242536, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1339356

RESUMEN

Abstract Chromium (VI) a highly toxic metal, a major constituent of industrial waste. It is continuously release in soil and water, causes environmental and health related issues, which is increasing public concern in developing countries like Pakistan. The basic aim of this study was isolation and screening of chromium resistant bacteria from industrial waste collected from Korangi and Lyari, Karachi (24˚52ʹ46.0ʺN 66˚59ʹ25.7ʺE and 24˚48ʹ37.5ʺN 67˚06ʹ52.6ʺE). Among total of 53 isolated strains, seven bacterial strains were selected through selective enrichment and identified on the basis of morphological and biochemical characteristics. These strains were designated as S11, S13, S17, S18, S30, S35 and S48, resistance was determined against varying concentrations of chromium (100-1500 mg/l). Two bacterial strains S35 and S48 showed maximum resistance to chromium (1600 mg/l). Bacterial strains S35 and S48 were identified through 16S rRNA sequence and showed 99% similarity to Bacillus paranthracis and Bacillus paramycoides. Furthermore, growth condition including temperature and pH were optimized for both bacterial strains, showed maximum growth at temperature 30ºC and at optimum pH 7.5 and 6.5 respectively. It is concluded that indigenous bacterial strains isolated from metal contaminated industrial effluent use their innate ability to transform toxic heavy metals to less or nontoxic form and can offer an effective tool for monitoring heavy metal contamination in the environment.


Resumo O cromo (VI), metal altamente tóxico, é um dos principais constituintes dos resíduos industriais. É liberado no solo e na água, causa problemas ambientais e de saúde de crescente preocupação pública em países em desenvolvimento como o Paquistão. O objetivo básico deste estudo foi o isolamento e a triagem de bactérias resistentes ao cromo de resíduos industriais coletados em Korangi e Lyari, Karachi (24˚52'46,0"N 66˚59'25,7"E e 24˚48'37,5"N 67˚06'52,6"E). Do total de 53 cepas isoladas, sete cepas bacterianas foram selecionadas por enriquecimento seletivo e identificadas com base em características morfológicas e bioquímicas. Essas cepas foram designadas como S11, S13, S17, S18, S30, S35 e S48, apresentaram alta resistência aos metais contra concentrações variáveis (100-1500 mg / l) de cromo. Já as cepas S35 e S48 foram identificadas por meio da sequência 16S rRNA e apresentaram 99% de similaridade com Bacillus paranthracis e Bacillus paramycoides. Além disso, as condições de crescimento incluindo temperatura e pH foram otimizadas e ambas as cepas bacterianas apresentaram crescimento máximo na temperatura de 30 ºC, enquanto seu pH ótimo foi observado em 7,5 e 6,5, respectivamente. Conclui-se que o potencial de resistência dessas bactérias resistentes ao cromo pode ser efetivamente utilizado na remoção de cromo de efluentes industriais contaminados. Técnicas de base biológica usando bactérias ajudarão a fornecer métodos mais baratos e ecológicos de remoção, recuperação e desintoxicação de cromo.


Asunto(s)
Cromo , Metales Pesados , Bacillus , Bacterias/genética , Biodegradación Ambiental , ARN Ribosómico 16S/genética , Residuos Industriales/análisis
3.
Braz. j. biol ; 83: e247562, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1339410

RESUMEN

Abstract To investigate the role of cow dung in soil reclamation and bio assimilation along with bio accumulation of heavy metals in earthworm (P. posthuma) (N=900) earthworms were used and treatment groups of CD-soil mixture of different proportion of cow dung were designed. Nonlethal doses of lead acetate and cadmium chloride were added in treatment groups. Mature P. posthuma were released in each experimental pot maintaining the favorable conditions. The pH, carbon, nitrogen, phosphorus, exchangeable cations, and heavy metal level of each mixture was evaluated. The results indicated that bio-assimilation of Pb and Cd by P. posthuma were significantly (P ˂ 0.01) higher in different soil-CD treatments compared to control. Highest bio-assimilation of both metals was observed in T1 of both groups (Pb = 563.8 mg/kg and Cd = 42.95 mg/kg). The contents of both metals were significantly (P ˂ 0.05) lowered in casting. The nutrient concentration in the final castings of all soil-CD treatments were also equally transformed from less or insoluble to more soluble and available for plants, except for carbon level which increased with CD proportion. It is concluded that cow dung as organic matter has a positive effect on soil reclamation and bio-assimilation of metals by P. posthuma.


RESUMO Para investigar o papel do esterco de vaca na recuperação do solo e bioassimilação, juntamente com a bioacumulação de metais pesados ​​em minhocas (P. posthuma) (N = 900), minhocas foram usadas e grupos de tratamento de mistura CD-solo de diferentes proporções de esterco de vaca foram projetados. Doses não letais de acetato de chumbo e cloreto de cádmio foram adicionadas aos grupos de tratamento. P. posthuma maduros foram liberados em cada vaso experimental, mantendo as condições favoráveis. Foram avaliados o pH, carbono, nitrogênio, fósforo, cátions trocáveis ​​e nível de metais pesados ​​de cada mistura. Os resultados indicaram que a bioassimilação de Pb e Cd por P. posthuma foi significativamente (P ˂ 0,01) maior em diferentes tratamentos de solo-CD em relação ao controle. A maior bioassimilação de ambos os metais foi observada em T1 de ambos os grupos (Pb = 563,8 mg / kg e Cd = 42,95 mg / kg). O conteúdo de ambos os metais foi significativamente (P ˂ 0,05) reduzido na fundição. A concentração de nutrientes nas fundições finais de todos os tratamentos de solo-CD também foi igualmente transformada de menos ou insolúvel para mais solúvel e disponível para as plantas, exceto o nível de carbono que aumenta com a proporção de CD. Conclui-se que o esterco de vaca como matéria orgânica tem um efeito positivo na recuperação do solo e na bioassimilação de metais por P. posthuma.


Asunto(s)
Animales , Femenino , Oligoquetos , Contaminantes del Suelo , Metales Pesados/análisis , Suelo , Cadmio , Bovinos , Bioacumulación
4.
Mar Pollut Bull ; 177: 113489, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35325795

RESUMEN

Heavy metal-contaminated wastes can threaten mangrove forests, one of the most biodiverse ecosystems in the world. The study evaluated the geospatial distribution of heavy metals concentrations in soils, the ecological and human health risks, and metal contents in soil fractions and mangrove organisms in the Botafogo estuary, Brazil, one of the most environmentally impacted estuaries in the country. The metal concentrations exceeded by up to 2.6-fold the geochemical background; 91%, 59%, 64%, 31%, and 82% of the soils were contaminated with Cr, Zn, Pb, Cu, and Ni, respectively. Adverse effects to the biota may occur due to Cr, Cu, Ni and Pb exposures. Contents of clay and organic matter were the main factors governing the distribution of metals in soil, contributing to up to 63% of the total variability. However, the geospatial modeling showed that the predictive ability of these variables varied spatially with the metal and location. The ecological and human health risks assessments indicated that the metal concentrations in soils are safe for the environment and human beings. There was a low transfer of metals from the soil to the biota, with values of sediment-biota accumulation factor (SBAF) and biological accumulation coefficients (BAC) lower than 1.0, except for Zn (SBAF = 13.1). The high Zn bioaccumulation by Crassostrea rhizophorae may be associated with the concentrations of Zn in the bioavailable fractions.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Ecosistema , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Medición de Riesgo , Suelo/química , Contaminantes del Suelo/análisis
5.
Ying Yong Sheng Tai Xue Bao ; 33(3): 855-864, 2022 Mar.
Artículo en Chino | MEDLINE | ID: mdl-35524541

RESUMEN

Human activities have severely polluted environments during industrialization. Rotifers are commonly used as model species for ecotoxicological assays. The sensitivities of ecotoxicological indices of rotifers highly depend on different pollutants. We summarized available ecotoxicological indices of rotifers, and reviewed their sensitivity to commonly investigated pollutants. Under the stress of heavy metals, the life-table demographic parameters, physiological and biochemical indices generally show high sensitivity. In response to persistent organic pollutants, sexual indices generally show higher sensitivity than asexual ones. Some studies showed that swimming speed revealed higher sensitivity after exposure to several pollutants compared with life-table demographic and population growth indices. We suggested to consider swimming speed of rotifer as an alternative index for ecotoxicological assays. Overall, this study would provide a guideline for rotifer ecotoxicological studies in the future.


Asunto(s)
Metales Pesados , Rotíferos , Contaminantes Químicos del Agua , Animales , Ecotoxicología , Humanos , Rotíferos/fisiología , Natación , Contaminantes Químicos del Agua/toxicidad
6.
Anal Chim Acta ; 1208: 339791, 2022 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-35525583

RESUMEN

Oxidative stress of aquatic microorganisms under heavy metal stress is closely reflected by metabolite changes in cells but it is very difficult to study due to the fast metabolism process and severe in-situ measurements hurdle. Herein, the oxidative stress of cadmium on Euglena gracilis was systematically studied through multi-combined techniques. In particular, for the first time electrochemical approach was associated with Raman spectroscopy imaging to vividly to investigate temporal-spatially varied oxidative stress and its effects on cells metabolism, in which former real-time measured a volcanic relation of extracellular hydrogen peroxide versus the increase of cadmium stress, while the latter shows the corresponding metabolic changes by Raman imaging of single cells. This work builds a bridge to unravel the mechanism of cellular oxidative stress under harsh conditions in a more systematic and holistic approach, while holding a great promise to construct heavy metal biosensors precisely monitoring high heavy metal tolerance strains for environmental modification.


Asunto(s)
Metales Pesados , Microalgas , Cadmio/toxicidad , Peróxido de Hidrógeno , Metales Pesados/química , Metales Pesados/toxicidad , Estrés Oxidativo
7.
PLoS One ; 17(5): e0268268, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35594243

RESUMEN

Field portable X-ray fluorescence (FP-XRF) has tremendous potential in geoenvironmental engineering as a qualitative assessment tool. Identification of the elevated concentrations of the selected elements (Cr, Cu, Mn, Ni, Pb, and Zn) in various geomaterials like soil-like-material (SLM), incinerated bottom ash (IBA), construction and demolition waste (CDW), zinc tailings (ZT) and fly ash (FA) was performed by FP-XRF and compared with the local soil-Delhi silt. Comparably higher concentrations (mg/kg) of Cr (401.0), Cu (499.0), Pb (532.0), Zn (608.0) in SLM, Cr (195.0), Cu (419.0), Ni (93.0), Pb (931.0), Zn (771.0) in IBA and Cr (195.0), Cu (4000.0), Pb (671.0), Zn (7122.0) in ZT were observed. CDW and FA showed similar concentrations range as in local soils. FP-XRF was also used in-situ on local soil at 11 sites to examine its ability to identify the elements with significant variations in concentrations. The results showed high variability in Cl and S concentration values across the 11 sites attributed to the changing moisture content and dissolved salts. The concentration range for the remaining elements were similar at all sites. The verification of the detected elements through visual inspection of the spectrum was also carried out.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Monitoreo del Ambiente/métodos , Plomo , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisis , Zinc
8.
Environ Monit Assess ; 194(6): 441, 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35596091

RESUMEN

Cuba is a country with considerable potential for economic growth, and special efforts are made to increase the agricultural output. As food production depends on the quality of soils, heavy metal concentrations were measured in 39 soils in the province of Mayabeque, Cuba, and interpreted in light of anthropogenic activities and pedogenic conditions (soil type and properties). With median concentrations of 1.8 Cd, 60.3 Cr, 48.1 Cu, 36.2 Ni, 16.7 Pb, 55.0 Zn, and 0.1 mg/kg Hg, soils of Mayabeque were mostly below Cuban quality reference values (QRV) representing benchmarks of quality standards but no official threshold values. Only Cd concentrations were in many cases above the QRV of 0.6 mg/kg and some Cu concentrations above the one of 83 mg/kg. While Cd, Cr, and Ni concentrations were rather pedogenically driven, Cu, Pb, Zn, and Hg contents were rather anthropogenically influenced. When evaluated statistically, Cd and Cr showed most times a significant influence of both sources. In contrast, Ni and Zn could not be significantly related with the origins investigated in this study. Hence, the allocation of heavy metal concentrations to pedogenic or anthropogenic contamination or pollution sources is tentative and needs further investigations. Nevertheless, the present data adds information on soil heavy metal concentrations in the Caribbean region, serves as reference before further industrial development, and sets the ground for adaptation of the QRV for Cd and possibly future national environmental standards.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes del Suelo , Cadmio , China , Cuba , Monitoreo del Ambiente , Plomo , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
9.
Anal Chim Acta ; 1208: 339824, 2022 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-35525586

RESUMEN

Luminescent organic molecules are of important realistic significance to the human health and ecological environment due to their fascinating applications. Here we report the design and synthesis of luminescent organic-molecules by introducing two or four NH-pyrazolate groups as mercury-binding moieties to aromatic cores. Interestingly, the new aromatic tetraphenylene-bridged multi-NH-pyrazoles exhibit strong fluorescence in both aggregate and solid state and constitutes highly selective proof-of-concept luminescent sensor for Hg(II) ion among various competitive transition-metal ions in both organic and mixed solutions via metal-nitrogen binding. Especially, the present sensor including two NH-pyrazolyl groups showed an extremely high sensitivity with low limit of detection of 7.26 and 3.67 nM. The proposed design strategy provides a wide scope for the construction of unique turn-on sensors with substantial potential in the sense of heavy metal pollution in enviromental water samples.


Asunto(s)
Mercurio , Metales Pesados , Colorantes Fluorescentes/química , Humanos , Iones , Espectrometría de Fluorescencia
10.
Environ Monit Assess ; 194(6): 410, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35532857

RESUMEN

A great amount of iron ore tailings from the collapse of the Fundão dam in Southeast Brazil was deposited in an extensive agricultural area. The presence of this material creates insecurity for the resumption of agricultural activities, especially the cultivation of vegetables, which can accumulate metals at potentially toxic levels. In this study, two vegetables consumed in the affected area, arugula and radish, were cultivated in tailings and in soil. Productivity, photosynthetic pigment content, photosynthetic performance, metal accumulation, and the possible risk to food safety were analyzed. The productivity of both vegetables, arugula and radish, did not differ between cultivation in tailings and in soil. There were no differences in pigment content nor substantial differences in the photosynthetic parameters of plants grown in the two substrates. Plants grown in tailings had higher Fe, Mn, and Na contents than those grown in soil, reflecting the higher levels of these elements in the former. There were no visual signs of metal toxicity for plants grown in the tailings. The levels of metals potentially ingested through estimated consumption of arugula and radish grown in the tailings were below the maximum allowable limits for human consumption. In addition, calculated risk indices suggest a low potential for harm to the health of consumers of cultivated vegetables in the tailings. The results presented here suggest that agricultural cultivation in the tailings is viable and contribute to the resumption of vegetable cultivation in the region affected by the tailings released with the collapse of the Fundão dam.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Colapso de la Estructura , Brasil , Monitoreo del Ambiente , Inocuidad de los Alimentos , Humanos , Metales , Metales Pesados/análisis , Plantas , Suelo , Contaminantes del Suelo/análisis , Verduras
11.
Zhongguo Zhong Yao Za Zhi ; 47(7): 1913-1920, 2022 Apr.
Artículo en Chino | MEDLINE | ID: mdl-35534262

RESUMEN

This study explored whether Sagittaria sagittifolia polysaccharides(SSP) activates the nuclear factor erythroid-2-related factor2(Nrf2)/heme oxygenase-1(HO-1) signaling pathway to protect against liver damage jointly induced by multiple heavy metals. First, based on the proportion of dietary intake of six heavy metals in rice available in Beijing market, a heavy metal mixture was prepared for inducing mouse liver injury and HepG2 cell injury. Forty male Kunming mice were divided into five groups: control group, model group, glutathione positive control group, and low-and high-dose SSP groups, with eight mice in each group. After 30 days of intragastric administration, the liver injury in mice was observed by HE staining. In the in vitro experiment, MTT assay was conducted to detect the effects of SSP at 0.25, 0.5, 1, and 2 mg·mL~(-1) on HepG2 cell survival at different time points. The content of alanine transaminase(ALT) and aspartate aminotransferase(AST) in the 48-h cell culture fluid was measured using micro-plate cultivation method, followed by the detection of the change in reactive oxygen species(ROS) content by flow cytometry. The mRNA expression levels of Nrf2 and HO-1 in cells were determined by RT-PCR, and their protein expression by Western blot. HE staining results showed that compared with the model group, the SSP administration groups exhibited significantly alleviated inflammatory cell infiltration and fatty infiltration in the liver, with better outcomes observed in the high-dose SSP group. In the in vitro MTT assay, compared with the model group, SSP at four concentrations all significantly increased the cell survival rate, decreased the ALT, AST, and ROS content(P<0.05), and down-regulated Nrf2 and HO-1 mRNA and protein expression(P<0.05). SSP significantly improves inflammatory infiltration in the liver tissue of mice exposed to a variety of heavy metals and corrects the liver fat degeneration, which may be related to its regulation of the Nrf2/HO-1 signaling pathway, reduction of ROS, and alleviation of oxidative damage.


Asunto(s)
Metales Pesados , Sagittaria , Animales , Hemo-Oxigenasa 1/genética , Hemo-Oxigenasa 1/metabolismo , Hígado , Masculino , Metales Pesados/metabolismo , Ratones , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Polisacáridos/farmacología , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sagittaria/genética , Sagittaria/metabolismo
12.
Toxicol Ind Health ; 38(5): 249-258, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35513769

RESUMEN

Amiodarone (AMD) is an antiarrhythmic drug that induces idiosyncratic toxicity. Environmental pollutants, including heavy metals, could interact with its toxicity by affecting pharmacokinetics and pharmacodynamics. Other levels of interaction could exist in yeast, such as oxidative stress and the general stress response. In this study, we investigated the interaction of mercury chloride (HgCl2) and cadmium chloride (CdCl2) with AMD toxicity on Saccharomyces cerevisiae. Interaction type - synergistic, additive, or antagonistic - was determined by median drug effect analysis using "CompuSyn". HgCl2 potentiated AMD toxicity at high doses (≥ 71.4 µm, which yielded more than 60% inhibition). CdCl2 acted similarly at high doses (≥ 57.9 µm). An antagonistic effect appeared at lower doses with both heavy metals (≤ 49.4 µm for HgCl2 and AMD; ≤ 18.9 µm for CdCl2 and AMD). The threshold concentrations (HgCl2 or CdCl2 combined with AMD) that switched the interaction from antagonistic to additive, and then to synergistic, were decreased in the yeast strain mutant in catalase (CTT1), suggesting an important role for this enzyme. Moreover, mutation of the nutrient sensing receptor gene GPR1 caused the synergistic interaction of CdCl2, but not HgCl2, with AMD to occur at the lowest tested concentrations (1.2 µm). The reverse was obtained with the mutant strain in calcium-manganese transporter gene PMR1, where the synergistic interaction of HgCl2 with AMD occurred at concentrations (20.7 µm) lower than that of the wild type (71.4 µm). These results demonstrated a dose-dependent interaction between the two heavy metals with AMD toxicity, and the involvement of oxidative stress, calcium homeostasis, and nutrient sensing in the observed interaction.


Asunto(s)
Amiodarona , Mercurio , Metales Pesados , Amiodarona/toxicidad , Cadmio/toxicidad , Calcio , Mercurio/toxicidad , Metales Pesados/toxicidad , Saccharomyces cerevisiae/genética
13.
Food Chem ; 389: 133093, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-35500406

RESUMEN

Auto-fluorescence of cellulose paper is often considered as an interfering fluorescence, which directly impedes the cellulose paper as a substrate material. This paper creatively explored the composition and properties of auto-fluorescence, and lignosulfonate was primarily speculated as the main source of auto-fluorescence. Surprisingly, its spatial solid phrase dispersion-induced fluorescence enhancement behavior was found. Then, cellulose paper was modified with Mn-doped ZnS quantum dots, and the prepared ratiometric fluorescent paper chip has good performances on morphology, stability, and fluorescence properties. Besides, the paper chip exhibited different fluorescence responses to three heavy metal ions in water sample. The limit of detection for Cd2+, Hg2+ and Pb2+ reached 1.61 nM, 0.01 nM, and 0.02 nM, respectively. In short, the molecular simulation results theoretically proved that heavy metal ions owned substitution affinity with lignosulfonate. Ultimately, this study was the first attempt to utilize paper-based auto-fluorescence, which could better accelerate the development of paper-based chips.


Asunto(s)
Mercurio , Metales Pesados , Puntos Cuánticos , Celulosa , Iones , Puntos Cuánticos/química
14.
J Synchrotron Radiat ; 29(Pt 3): 765-774, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35511009

RESUMEN

Synchrotron radiation-based techniques [X-ray absorption near-edge structure (XANES) and X-ray fluorescence (XRF)] combined with inductively coupled plasma-mass spectrometry (ICP-MS) were used for the assessment of heavy metals concentrations as well as lead (Pb) and nickel (Ni) speciation in airborne particulate matter (PM10) over two residential sites in Greater Cairo. Nineteen 24 h high-volume samples collected at Giza (G) Square and Helwan (H) University (Egypt) were selected for this study. Mean concentrations of heavy metals in PM10 at both sites were found to have the same descending order of Pb > Cu > Ni > Cd > Co > As, of which concentrations of Pb, Cu, Ni and Cd in H samples were higher than those in G samples. For Pb, synchrotron-based XRF results were in good agreement with concentrations obtained by ICP-MS. The XANES spectra of PM10 at the Pb L2-edge and Ni K-edge were compared with those of Pb and Ni in model standard compounds to provide information on the potential oxidation states as well as the chemical forms of those elements. The data show that Pb has similar chemical environments in both series G and H with the predominance of Pb2+ oxidation state. Nickel was found as Ni(OH)2, NiO and Ni metal in the analyzed samples. However, the content of Ni in the background filter shows a very strong interference with that of the collected PM10. Carcinogenic and non-carcinogenic risks resulting from the inhalation of the studied heavy metals were assessed for children and adult residents and were found below the safe limits, at both sites.


Asunto(s)
Metales Pesados , Material Particulado , Adulto , Cadmio/análisis , Niño , Monitoreo del Ambiente , Humanos , Plomo/análisis , Metales Pesados/análisis , Níquel/análisis , Material Particulado/análisis , Medición de Riesgo , Sincrotrones
15.
J Environ Manage ; 315: 115184, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35523070

RESUMEN

Phytoremediation is a cost-effective, environmentally-friendly and emerging remediation technology that treats polluted areas using plants, having the potential to restore ecosystems and make compromised areas useable again, therefore returning a resource to community use. In the present work a study was conducted on the contamination of soil by heavy metals (Zn, Pb, Cr, Cd, and Co) in the mining area of Angouran (northwestern Iran) and on their uptake by 25 native species present in the mining district, in order to evaluate their potential use in phytoremediation interventions. Plant and soils from three sites around the mine were sampled and characterized, and metals accumulation and translocation were evaluated. Principal Component Analysis (PCA) and Cluster Analysis (CA) were applied to study the behavior of species in the accumulation and translocation of the elements in their tissues. The contents of Zn, Pb, Cr, Cd, and Co in the studied plants were, respectively, 31.77-723.05, 7.78-233.25, 1.77-21.57, 0.04-7.92, and 0.15-9.97 mg/kg. Among the 25 species, 13 plants showed translocation factor greater than one (TF > 1) for Zn, 14 for Pb, 3 for Cr, 10 for Co, and 6 for Cd. Marrubium cuneatum having an accumulation factor greater than one (AF > 1) for Zn and bioconcentration factor greater than one (BCF >1) for Cd can be considered as an accumulator and stabilizer for Zn and Cd, respectively. Also, the highest value of Pb (233.25 mg/kg) and Cr (21.57 mg/kg) were found in the shoot of this plant. Psathyrostachys fragilis with BCF >1 for Co and maximum Pb accumulation in the root can be used as a stabilizer plant for Pb and Co-contaminated soils. Besides, Stipa arabica and Verbascum speciosum, with TF > 1 and rather high AF, could be considered suitable species for removing Zn and Pb through phytoextraction. This research showed that some native species in the study area have considerable potential for developing phytoremediation strategies.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Biodegradación Ambiental , Cadmio/análisis , Ecosistema , Irán , Plomo/análisis , Metales Pesados/análisis , Minería , Plantas , Poaceae , Suelo , Contaminantes del Suelo/análisis , Zinc/análisis
16.
Inorg Chem ; 61(20): 7847-7858, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35523200

RESUMEN

Increasing global environmental pollution due to heavy metal ions raises the importance of research on new multifunctional materials for simultaneous detection and removal of these contaminants from water resources. In this study, we report a microporous 8-connected Zr4+ metal-organic framework (MOF) based on a terephthalate ligand decorated with a chelating 2-picolylamine side group (dMOR-2), which shows highly efficient fluorescence sensing and sorption of heavy metal cations. We demonstrate by detailed fluorescence studies the ability of a water-dispersible composite of dMOR-2 with polyvinylpyrrolidone for real-time detection of Cu2+, Pb2+, and Hg2+ in aqueous media. The limits of detection were found to be below 2 ppb for these species, while the system's performance is not affected by the presence of other potentially competitive ions. In addition, sorption studies showed that a composite of dMOR-2 with calcium alginate (dMOR-2@CaA) is an excellent sorbent for Pb2+ and Cu2+ ions with capacities of 376 ± 15 and 117 ± 4 mg per gram of dMOR-2@CaA, respectively, while displaying the capability for simultaneous removal of various heavy metal ions in low initial concentrations and in the presence of large excesses of other cationic species. Structural and spectroscopic studies with model ligands analogous to our material's receptor unit showed chelation to the 2-picolylamine moiety to be the main binding mode of metal ions to dMOR-2. Overall, dMOR-2 is shown to represent a rare example of a MOF, which combines sensitive fluorescence detection and high sorption capacity for heavy metal ions.


Asunto(s)
Estructuras Metalorgánicas , Metales Pesados , Colorantes , Iones , Plomo , Estructuras Metalorgánicas/química , Agua
17.
Mar Environ Res ; 177: 105637, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35526361

RESUMEN

Using a short food web, i.e. from prey (macro-algae) to predator (limpet), this study investigated the concentrations and biomagnification of heavy metals from macro-algae (Ralfsia verrucosa, Ulva lactuca and Gelidium pristoides) to limpet (Scutellastra cochlear, S. longicosta, S. granularis and Cellana capensis) species. Samples were collected from four sites (Mbhashe; Mthatha; Hluleka; Silaka Mouth) in four seasons (winter 2019; spring 2019; summer 2020; spring 2020). In the laboratory samples were digested with the normal protocols, subsequently analysed for heavy metals using inductively coupled plasma optical emission spectrometry (ICP-OES), while δ15N and δ13C isotopes were analysed with Isotope Ratio Mass Spectrometer (IRMS). There were significant differences of heavy metals concentration between species of macro-algae and limpet, and metal concentration was species-specific. Spatio-temporal differences of (δ13C) isotope was evident, indicating a wide source of energy. Using (δ15N) as a proxy for biomagnification (BMF) of metals, As did not show any sign of biomagnification (BMF<1) among all seasons and sites. Though mercury and Ni had BMF >1, negative regression slope showed biodilution of these metals to the next trophic level. The toxic Cd, Pb, and essential metals Zn and Cu indicated possible biomagnification (BMF >1) between sites and seasons respectively. This study showed that the selected limpet species are notable accumulators of heavy metals and these contaminants have the potential to biomagnify in the next trophic level suggesting that they are possibly unfit for human consumption in these study sites.


Asunto(s)
Gastrópodos , Metales Pesados , Contaminantes Químicos del Agua , Animales , Monitoreo del Ambiente , Cadena Alimentaria , Humanos , Isótopos/análisis , Metales Pesados/análisis , Sudáfrica , Contaminantes Químicos del Agua/análisis
18.
Bioresour Technol ; 355: 127259, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35550924

RESUMEN

The coexistence of nitrate (NO3--N) and heavy metals in the aquatic environment causes harm to both the aquatic ecosystem and human health. Here, fungal-sponge composite carriers (FSC) were assembled and immobilized with strain WZ39 in a bioreactor to remove NO3--N, Ca2+, and Cd2+. Stable bioreactor performance under heavy metal pressure was achieved. The highest removal efficiencies of NO3--N, Ca2+, and Cd2+ reached 100, 71.81, and 92.50%, respectively. Bacteria and precipitates were found in fungal mycelium and sponge. The precipitates composed of Ca3.9(Ca4.7Cd0.7)(PO4)6(OH)1.8, CaCO3, and CdCO3. Fluorescence excitation-emission matrix (EEM) and flow cytometric (FCM) analysis indicated bacteria in FSC exhibited a strong metabolic activity and high percentage of intact cells under heavy metal stress. High-throughput sequencing results showed Pseudomonas sp. WZ39 played a major role in the bioreactor. The potential functions associated with metabolism, heavy metal transfer, and biofilm formation had high relative abundance in the bioreactor.


Asunto(s)
Metales Pesados , Nitratos , Bacterias/genética , Biomineralización , Reactores Biológicos , Cadmio , Calcio , Desnitrificación , Ecosistema , Humanos , Óxidos de Nitrógeno
19.
Biomed Res Int ; 2022: 6811613, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35509711

RESUMEN

Medicinal plants have great importance to the consumer health, as beside beneficial compounds, plants can accumulate essential and nonessential metals from soil and surrounding environments, leading to consumer health risks. Assuming this, the present study is aimed at evaluating the elemental composition and daily dose standardization based on essential and nonessential trace element presence in of bark, leaves, and roots of Berberis baluchistanica Ahrendt, a common medicinal plant used as a folk medicine in the region. Atomic absorption and flame emission spectroscopy were performed to analyze the presence of essential and nonessential elements manganese (Mn), copper (Cu), lead (Pb), nickel (Ni), iron (Fe), sodium (Na), and potassium (K). Among the essential elements, K was present at high concentrations in the bark (8926.98 ± 0.32 µg/g), leaves (7922.77 ± 0.42 µg/g), and roots (6668.5 ± 0.96 µg/g) of the plant. The estimated concentration of Na was higher in leaves (1782.56 ± 0.13 µg/g), followed by roots (1089.5 ± 0.71 µg/g) and bark (572.8 ± 0.62 µg/g). The Fe concentration varied in the range of 394.7 ± 0.3 µg/g in bark, 1298.3 ± 0.54 µg/g in leaves, and 1208.9 ± 0.7 µg/g in roots. The trace transition element Mn was highest in leaves (42.7 ± 0.99 µg/g), followed by roots (33.5 ± 0.94 µg/g) and bark (22 ± 1 µg/g). The Cu concentration was low, ranging from 20.1 ± 0.63 to 22.67 ± 0.7 µg/g in leaves, bark, and roots. The obtained concentration of nonessential element Pb was relatively lower than the permissible range (10 mgL-1) established by the World Health Organization. The elemental concentrations in all parts were within the set limits for provisional tolerable daily maximum intake (PTDMI) and provisional tolerable weekly intake (PTWI), and the hazard quotient index (HQ) was below 1 for all toxic metals. The micro and macroelemental distribution and the overall medicinal potential of any medicinal plant can be correlated for dose risk estimation, which will be useful in providing knowledge regarding the contraindication associated with folk medicines. In the present study, based on the elemental composition, it was calculated that the daily safe dose for Berberis baluchistanica is approximately 2-5 g/day of raw powder for an adult, which must not be exceeded to this safe range.


Asunto(s)
Berberis , Metales Pesados , Plantas Medicinales , Oligoelementos , Plomo/análisis , Metales Pesados/química , Corteza de la Planta/química , Hojas de la Planta/química , Estándares de Referencia , Oligoelementos/análisis
20.
Sci Rep ; 12(1): 7172, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35504976

RESUMEN

The present study aims to assess the effect of a heavy metal burden on general health, biochemical parameters, an antioxidant enzyme, and reproductive hormone parameters in adult male brick kiln workers from Pakistan. The study participants (n = 546) provided demographic data including general health as well as body mass index. Blood was collected to quantitatively assess hematological, biochemical, and reproductive hormone parameters as well as heavy metal concentrations using both atomic absorption spectroscopy (AAS) and particle-induced X-ray emission (PIXE). The data showed that 10% of the brick kiln workers were underweight and 10% obese (P = 0.059), with workers also reporting multiple health issues. Heavy metal concentrations utilizing AAS revealed significantly (p = 0.000) higher levels of cadmium, chromium, and nickel, while PIXE detected more than permissible levels of Si, P, S, Cl, K, Ca, Zn, Ti (p = 0.052), Mn (p = 0.017), Fe (p = 0.055), Co (p = 0.011), Ni (p = 0.045), and Cu (p = 0.003), in the blood of kiln workers. Moreover, a significant increase in platelet count (P = 0.010), a decrease in sodium dismutase levels (p = 0.006), a major increase in reactive oxygen species (p = 0.001), and a reduction in protein content (p = 0.013) were evident. A significant increase in cortisol levels (p = 0.000) among the workers group was also observed. The concentration of LH and FSH increased significantly (p = 0.000), while that of testosterone decreased (p = 0.000) in the worker group compared with controls. A significant inverse relationship was found between cortisol, LH (r = - 0.380), and FSH (r = - 0.946), while a positive correlation between cortisol and testosterone was also evident (r = 0.164). The study concludes that increased heavy metal burden in the blood of brick kiln workers exposes them to the development of general and reproductive health problems due to compromised antioxidant enzyme levels, increased oxidative stress conditions, and a disturbing reproductive axis.


Asunto(s)
Metales Pesados , Exposición Profesional , Adulto , Antioxidantes/metabolismo , Biomarcadores , Hormona Folículo Estimulante , Humanos , Hidrocortisona/análisis , Masculino , Metales Pesados/análisis , Exposición Profesional/efectos adversos , Exposición Profesional/análisis , Testosterona/análisis
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