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1.
Food Chem Toxicol ; 187: 114586, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38493978

RESUMO

The risk assessment of heavy metals in tea is extremely imperative for the health of tea consumers. However, the effects of varietal variations and seasonal fluctuations on heavy metals and minerals in tea plants remain unclear. Inductively coupled plasma optical emission spectrometry (ICP-OES) was used to evaluate the contents of aluminum (Al), manganese (Mn), magnesium (Mg), boron (B), calcium (Ca), copper (Cu), cobalt (Co), iron (Fe), sodium (Na), zinc (Zn), arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), and antimony (Sb) in the two categories of young leaves (YL) and mature leaves (ML) of tea (Camellia sinensis) cultivars throughout the growing seasons. The results showed significant variations in the contents of the investigated nutrients both among the different cultivars and growing seasons as well. Furthermore, the average concentrations of Al, Mn, Mg, B, Ca, Cu, Co, Fe, Na, Zn, As, Cd, Cr, Ni, and Sb in YL ranged, from 671.58-2209.12, 1260.58-1902.21, 2290.56-2995.36, 91.18-164.68, 821.95-5708.20, 2.55-3.80, 3.96-25.22, 37.95-202.84, 81.79-205.05, 27.10-69.67, 0.028-0.053, 0.065-0.127, 2.40-3.73, 10.57-12.64, 0.11-0.14 mg kg-1, respectively. In ML, the concentrations were 2626.41-7834.60, 3980.82-6473.64, 3335.38-4537.48, 327.33-501.70, 9619.89-13153.68, 4.23-8.18, 17.23-34.20, 329.39-567.19, 145.36-248.69, 40.50-81.42, 0.089-0.169, 0.23-0.27, 5.24-7.89, 18.51-23.97, 0.15-0.19 mg kg-1, respectively. The contents of all analyzed nutrients were found to be higher in ML than in YL. Target hazard quotients (THQ) of As, Cd, Cr, Ni, and Sb, as well as the hazard index (HI), were all less than one, suggesting no risk to human health via tea consumption. This research might provide the groundwork for essential minerals recommendations, as well as a better understanding and management of heavy metal risks in tea.


Assuntos
Arsênio , Camellia sinensis , Metais Pesados , Humanos , Estações do Ano , Cádmio/análise , Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Metais Pesados/análise , Arsênio/análise , Minerais , Cromo/análise , Níquel/análise , Manganês/análise , Alumínio/análise , Medição de Risco , Zinco/análise , Chá/química
2.
Sci Total Environ ; 913: 169641, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38159765

RESUMO

This study investigated the fate of phosphorus (P) in 8 full-scale municipal wastewater treatment plants (WWTPs) in Shanghai, China, in which both biological nutrient removal and aluminum-based chemical phosphorus removal were used. The results showed that 83.8-98.9 % P was transferred to the sludge in the 8 WWTPs by both chemical and biological reactions. P speciation analysis indicated that chemical P precipitates accounted for 84.3 % in the activated sludge, of which crystalline AlPO4 and amorphous iron­phosphorus compounds (FePs) were the main components. Sludge with more water-soluble and weakly adsorbed P was generated in the anaerobic-anoxic-oxic (A/A/O) process than in other processes. Among the 8 WWTPs, the one with the largest flow rate and relatively short sludge retention time (SRT) had the best potential to release P from all types of sludge. The recovery potential of P from thickened sludge can be improved by separately thickening the sludge produced in the high-efficiency sedimentation tank or feeding it into the dewatering process directly. Different P removal chemicals and dosing points changed the amount of chemical precipitate formed but had little effect on the composition of P accumulating organisms (PAOs) at the genus level. Although aluminum-based coagulants were applied in the investigated WWTPs, Fe in wastewater had the most positive effect on the proliferation of PAOs. The synthesis of polyphosphate was also related to the metabolism of PAOs as it affected transmembrane inorganic phosphate (Pi) transport and polyhydroxybutyrate (PHB) synthesis. The in-depth understanding of the fate of P is beneficial to improve P recovery efficiency in WWTPs.


Assuntos
Esgotos , Purificação da Água , Esgotos/química , Fósforo/análise , Alumínio/análise , Sais , China , Polifosfatos/análise , Reatores Biológicos , Anticorpos , Eliminação de Resíduos Líquidos/métodos
3.
Chemosphere ; 346: 140643, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37939924

RESUMO

The effects of two types of layered double hydroxides (LDH) in-situ treatment on sediment phosphorus (P) mobilization and microbial community's structure were studied comparatively. The results presented that magnesium/aluminum-based (MA) and magnesium/iron (MF)-based LDH displayed great phosphate uptake ability in aqueous solution in a broad pH range of 3-8. The maximum phosphate sorption capacity of MA was 64.89 mg/g, around four times greater than that of MF (14.32 mg/g). Most of phosphate bound by MA and MF is hard to re-liberate under reduction and ordinary pH (5-9) conditions. In the in-situ remediation, the MA and MF capping/amendment both prevented P migration from the sediment to the overlying water (OL-water) under long-term anaerobic conditions, and MA had a better interception efficiency compared to MF in the same application mode. MA amendment significantly reduced mobile P (Mob-P) content in sediment and could remain its stable Mob-P inactivation capacity over a wide pH range. On the contrary, MF amendment increased Mob-P content in sediment and exhibited a variable ability to inactivate Mob-P under elevated pH conditions. MF can decrease Mob-P content at pH of 7 and 11 but increase Mob-P content at pH of 8-10. Under resuspension conditions, MA and MF capping groups still maintained low P levels in OL-water, while MA capping simultaneously showed a certain degree of resistance to sediment resuspension, but it had a weaker stabilizing effect for sediment than MF. Microbial community analysis manifested neither MA nor MF addition observably altered the sediment microbial diversity, but impacted the functional microorganisms' abundance and reshaped the microbial community's structure, intervening the sediment-P stabilization. Viewed from environmental friendliness, control efficiency, stability of P fixation capacity, and application convenience, MA capping wrapped by fabric is more suitable for addressing internal P loading in eutrophic lakes and holds great potential application.


Assuntos
Fósforo , Poluentes Químicos da Água , Fósforo/química , Magnésio/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Fosfatos/farmacologia , Fosfatos/análise , Água/química , Lagos/química , Alumínio/análise
4.
Environ Sci Pollut Res Int ; 30(59): 123643-123656, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37991616

RESUMO

The global "copper-poor and aluminum-rich" situation has made the possibility of "copper saving with aluminum" an important topic. This study established a framework for analyzing multiple substances' coupled flows at the product level based on material flow analysis (MFA), and took the household air conditioning system of the Chinese mainland in 2020 as an example to characterize the coupled flows of aluminum and copper. The results showed that the system consumed 0.69 million tons of aluminum and 2.10 million tons of copper, and discharged 0.17 million tons of aluminum and 0.43 million tons of copper to the environment cumulatively to achieve 13.2 million terajoules of final heat exchanged and serve 1.24 billion square meters during lifetime in mainland China alone, secondary aluminum and copper accounted for only 22.61% and 24.83% of the total consumption, and the in-use stocks increased by 0.19 million tons of aluminum and 0.70 million tons of copper. The external dependency of copper ore was 92.83%, which was significantly higher than the 44.29% of bauxite. The comprehensive utilization efficiency of copper reached 77.88%, which was slightly higher than the 70.80% of aluminum. The conclusion indicates that under the premise of meeting use requirements, promoting "replacing copper with aluminum" can improve the stability and safety of China's material supply chain, but there is a need to further boost the production efficiency of aluminum in primary production.


Assuntos
Alumínio , Cobre , Alumínio/análise , Cobre/análise , Ar Condicionado , China , Óxido de Alumínio/análise
5.
ACS Chem Neurosci ; 14(15): 2792-2801, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37436111

RESUMO

A new anthracene-based probe (E)-N'-(1-(anthracen-9-yl)ethylidene)-2-hydroxybenzohydrazide (AHB) has been efficiently synthesized and characterized by various spectroscopic methods. It exhibits extremely selective and sensitive fluorometric sensing of Al3+ ions with a large enhancement in the fluorescent intensity due to the restricted photoinduced electron transfer (PET) mechanism with a chelation-enhanced fluorescence (CHEF) effect. The AHB-Al3+ complex shows a remarkably low limit of detection at 0.498 nM. The binding mechanism has been proposed based on Job's plot, 1H NMR titration, Fourier transform infrared (FT-IR), high-resolution mass spectrometry (HRMS), and density functional theory (DFT) studies. The chemosensor is reusable and reversible in the presence of ctDNA. The practical usability of the fluorosensor has been established by a test strip kit. Further, the therapeutic potential of AHB against Al3+ ion-induced tau protein toxicity has been tested in the eye of Alzheimer's disease (AD) model of Drosophila via metal chelation therapy. AHB shows great therapeutic potential with 53.3% rescue in the eye phenotype. The in vivo interaction study of AHB with Al3+ in the gut tissue of Drosophila confirms its sensing efficiency in the biological environment. A detailed comparison table included evaluates the effectiveness of AHB.


Assuntos
Alumínio , Doença de Alzheimer , Animais , Alumínio/análise , Alumínio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Doença de Alzheimer/tratamento farmacológico , Drosophila , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Antracenos
6.
Anal Bioanal Chem ; 415(18): 4501-4510, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37041278

RESUMO

In the present work, the potential benefit of using multi-cumulative trapping headspace extraction was explored by comparing the results using solid-phase microextraction (SPME) coated with divinylbenzene/carboxen/polydimethylsiloxane and a probe-like tool coated with polydimethylsiloxane. The efficiency of a single 30-min extraction, already explored in previous work, was compared with that of multiple shorter extractions. We evaluated three different conditions, i.e., three repeated extractions for 10 min each from different sample vials (for both the probe-like tool and SPME) or from the same vial (for SPME) containing brewed coffee. The entire study was performed using comprehensive two-dimensional gas chromatography coupled with mass spectrometry. The two-dimensional plots were aligned and integrated using a tile-sum approach before any statistical analysis. A detailed comparison of all the tested conditions was performed on a set of 25 targeted compounds. Although a single 30-min extraction using the probe-like tool provided a significantly higher compound intensity than SPME single extraction, the use of multiple shorter extractions with SPME showed similar results. However, multiple extractions with the probe-like tool showed a greater increase in the number of extracted compounds. Furthermore, an untargeted cross-sample comparison was performed to evaluate the ability of the two tested tools and the different extraction procedures in differentiating between espresso-brewed coffee samples obtained from capsules made of different packaging materials (i.e., compostable capsules, aluminum capsules, aluminum multilayer pack). The highest explained variance was obtained using the probe-like tool and multiple extractions (91.6% compared to 83.9% of the single extraction); nevertheless, SPME multiple extractions showed similar results with 88.3% of variance explained.


Assuntos
Café , Odorantes , Café/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Alumínio/análise , Cápsulas , Microextração em Fase Sólida/métodos , Dimetilpolisiloxanos
7.
Biol Trace Elem Res ; 201(11): 5455-5467, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36701086

RESUMO

Trace elements (TE) contamination of foods and beverages constitutes a public health issue. In this context, the main objective of this study was to determine metals and metalloids content in coffee and to assess the health risks associated with contaminated coffee consumption. To this end, 44 samples of coffee from different origins, forms, and packaging types were analyzed. TE analysis was performed by ICP-MS after digestion. The data analysis was based on principal components analysis (PCA) and analysis of variance (ANOVA). Health risk assessment was determined by the estimated daily intake (EDI), target hazard quotient (THQ), and hazard index (HI). The findings showed that TE levels in coffee varied widely. The highest levels were related to aluminum (Al) (59.88 ± 54.86 mg/kg), manganese (Mn) (16.26 ± 24.59 mg/kg), copper (Cu) (11.60 ± 11.55 mg/kg), and cadmium (Cd) (9.92 ± 10.32 mg/kg). In terms of coffee form and packaging type, a significant difference (P < 0.0001) was observed in nickel (Ni), chromium (Cr), zinc (Zn), cobalt (Co), Cu, Mn, and Al content. The highest EDI was found in Al (0.0109 mg/kg BW/day) in ground coffee packaged in capsules. In terms of chronic daily intake (CDI), Cd and Al were above the reference dose (RfD). THQ of these elements were greater than 1.0, and HI was above the value of 1.0 in different forms of coffee. More interdisciplinary research on the relationships between the metal concentrations in coffee samples and those in feed, water, and soil would be quite interesting.


Assuntos
Metais Pesados , Oligoelementos , Oligoelementos/análise , Metais Pesados/análise , Café , Cádmio/análise , Manganês/análise , Alumínio/análise , Medição de Risco , Monitoramento Ambiental
8.
Sci Total Environ ; 861: 160683, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36481151

RESUMO

Coagulants such as polyaluminium chloride (PAC) are widely used for removing phosphorus from eutrophic water, but its application for water treatment can potentially harm the environment. In this study, a four-timepoint exposure experiment was performed at week 1, 3, 7 and 10 to investigate how microbial communities in lake sediments respond to different concentrations of PAC (RS (raw lake water with nothing added), Low, Medium and High). The results showed that, while PAC can efficiently decrease the amount of C, N and P in lake water, the presence of residual aluminum and aluminum precipitates can greatly affect the microbial communities in lake sediments. In particular, different concentrations of PAC and exposure time affected the microbial diversity and structure of lake sediments, with changes being especially obvious at high concentration of PAC after 10 weeks of exposure. Moreover, the use of PAC significantly increased the relative abundances of Gammaproteobacteria and Competibacter, while reducing those of Thermodesulfovibrionia, Vicinamibacterales, and BSV26 in time- and concentration-dependent manners. Network analysis further showed strong correlations between differential bacterial species of PAC in high concentration at 10 weeks, which further suggested that PAC treatment changed the complex structure of microbiota in lake sediment. Finally, correlation analysis indicated a close connection between water parameters and differential species induced by PAC treatment. Overall, PAC contamination changed the microbial communities at different taxonomy levels and influenced the functional pathways to potentiate the P removal, and the results offered interesting insights into the use of PAC in water treatment and its impact on biogeochemical cycling. These results indicated that more attention need to be paid to the potential impact of chemical phosphorus removing reagents on the environment, including eutrophic water.


Assuntos
Alumínio , Microbiota , Alumínio/análise , Bactérias , Lagos/química , Fósforo/análise
9.
Anal Bioanal Chem ; 415(13): 2511-2521, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36482082

RESUMO

The present paper discusses the use of a high-concentration-capacity tool, HiSorb, to investigate the impact of capsule material on the aroma profile of espresso-brewed coffee. The specific high-concentration-capacity probe used is characterized by a sorbent volume (63 µL) intermediate between the solid-phase microextraction (SPME) fiber (0.6 µL) and the stir-bar sorptive extraction rod (126 µL). The extraction performance of the HiSorb was compared, in terms of both absolute signal and compound coverage, with both an equivalent sorbent (polydimethylsiloxane) and a divinylbenzene/carboxen/polydimethylsiloxane SPME fiber using both targeted and untargeted approaches. The HiSorb showed superior extraction compared with the SPME fibers. The HiSorb was then optimized in terms of extraction time and temperature and used to investigate the volatile profile of 23 espresso-brewed coffees prepared with capsules made of different materials-aluminum, compostable, and aluminum multilayer pack-prepared using a refillable capsule. Comprehensive two-dimensional gas chromatography equipped with a reverse fill/flush flow modulator and coupled to mass spectrometry was used to obtain a chromatographic fingerprint of the volatile profile of the brewed coffee. The data were aligned and compared using a tile-based approach, and the results were obtained by performing raw data mining within the same software platform. The data mining enabled the extraction of informative features responsible for the differentiation between the different capsule materials, showing a significant depletion in aroma intensity in the compostable capsule.


Assuntos
Café , Odorantes , Cromatografia Gasosa-Espectrometria de Massas/métodos , Café/química , Odorantes/análise , Alumínio/análise , Microextração em Fase Sólida/métodos
10.
Braz. j. biol ; 83: 1-8, 2023. graf, tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468806

RESUMO

Although richness and distribution of woody species in the Cerrado physiognomies have been extensively studied, the shifts of woody species from savanna physiognomies to dry forests have not yet been addressed. Here, we investigate the effect of soil physical-chemical traits on the woody species turnover between adjacent cerrado stricto sensu and dry forest physiognomies. Woody species were surveyed, and soil and topographic variables measured, in 30 10×40 m plots systematically distributed, with 15 plots in each physiognomy. We found a spatially structured distribution of woody species, and differences of soil traits between cerrado stricto sensu and dry forest areas, mainly related to the aluminum saturation, base saturation, and available phosphorus. Aluminum saturation increased toward the savanna area, while base saturation increased toward the dry forest. Most woody species predominated in one physiognomy, such as Callisthene major in the cerrado stricto sensu and Anadenanthera colubrina in the dry forest. Only 20% of the species were widely distributed across both physiognomies or, not often, restricted to the intermediary values of the soil gradient. General results indicate that contrasting soil traits between cerrado stricto sensu and dry forest produce a strongly spatially organized and sharp transition in terms of species distribution between these physiognomies.


Embora a distribuição e a riqueza em espécies arbóreas nas fitofisionomias do Cerrado venham sendo bastante estudadas, a transição entre savanas e florestas deciduais ainda não foi abordada. Investigamos o efeito de características físico-químicas do solo sobre a distribuição de espécies arbóreas em região de contato entre cerrado sentido restrito e floresta estacional decidual (FED). As espécies arbóreas foram amostradas sistematicamente, e variáveis de topografia e características do solo foram medidas em 30 parcelas de 10×40 m, sendo 15 parcelas em cada fisionomia. A distribuição das espécies arbóreas foi espacialmente estruturada, e as características do solo diferiram entre as áreas de cerrado sentido restrito e FED, principalmente relacionadas à saturação de alumínio, saturação de bases e teores de fósforo. A saturação de alumínio aumentou em direção ao cerrado sentido restrito, enquanto a saturação de bases aumentou em direção à FED. A maioria das espécies arbóreas predominou em uma das fisionomias, como Callisthene major em cerrado sentido restrito e Anadenanthera colubrina em FED. Apenas 20% das espécies foram amplamente distribuídas em ambas as fisionomias ou, em poucos casos, restritas aos valores intermediários do gradiente de solo. Os resultados indicam um forte contraste de características do solo entre o cerrado sentido restrito e a FED, assim como uma transição acentuada e espacialmente organizada quanto à distribuição de espécies arbóreas.


Assuntos
Alumínio/análise , Florestas , Fósforo/análise , Pradaria , Solo/química
11.
Artigo em Inglês | MEDLINE | ID: mdl-36231252

RESUMO

Tea plants can accumulate aluminum (Al) in their leaves to a greater extent than most other edible plants. Few studies, however, address the Al concentration in leaves at different positions, which is important information for tea quality control. Leaves from four different cultivars of Camellia sinensis L. grown in Hawaii were analyzed for Al concentrations at 10 different leaf positions. Each cultivar was harvested in the winter and summer to determine seasonal variations of Al concentrations in the leaves. The results showed that Al concentrations in the winter leaves were an average of 1.2-fold higher than those in the summer leaves, although the seasonal variations were not statistically significant. The total Al concentration of successively lower leaves showed an exponential increase (R2 ≥ 0.900) for all four cultivars in the summer season, whereas those of the winter leaves fit a bi-phase linear regression (R2 ≥ 0.968). The regression of the Al concentrations against the top-5 leaf positions in the winter season fit one linear regression, while that against leaf positions 6-11 fit another linear regression. The average Al concentrations between the third leaf and the shoot plus first two leaves increased approximately 2.7-fold and 1.9-fold for all cultivars in the winter and summer months, respectively. The Al concentrations in the rest of the leaves increased approximately 1.5-fold in a sequential order. The target hazard quotient being between 1.69 × 10-2 and 5.06 × 10-1 in the tea leaf samples of the four cultivars in Hawaii were all less than 1, suggesting negligible health risks for consumers. The results of this study may be useful for directing harvest practices and estimating tea quality.


Assuntos
Camellia sinensis , Alumínio/análise , Folhas de Planta/química , Estações do Ano , Chá
12.
Artigo em Inglês | MEDLINE | ID: mdl-36141460

RESUMO

Children are highly vulnerable to chemical exposure. Thus, metal and metalloid in infant formulas are a concern, although studies in this regard are still relatively scarce. Thus, the presence of aluminum, arsenic, cadmium, tin, mercury, lead, and uranium was investigated in infant formulas marketed in Brazil by inductively coupled plasma mass spectrometry, and the Target Hazard Quotients (THQ) and Target Cancer Risk (TCR) were calculated in to assess the potential risk of toxicity for children who consume these products continuously. Aluminum ranging from 0.432 ± 0.049 to 1.241 ± 0.113 mg·kg-1, arsenic from 0.012 ± 0.009 to 0.034 ± 0.006 mg·kg-1, and tin from 0.007 ± 0.003 to 0.095 ± 0.024 mg·kg-1 were the major elements, while cadmium and uranium were present at the lowest concentrations. According to the THQ, arsenic contents in infant formulas showed a THQ > 1, indicating potential health risk concerns for newborns or children. Minimal carcinogenic risks were observed for the elements considered carcinogenic. Metabolic and nutritional interactions are also discussed. This study indicates the need to improve infant formula surveillance concerning contamination by potentially toxic and carcinogenic elements.


Assuntos
Arsênio , Mercúrio , Metaloides , Metais Pesados , Neoplasias , Urânio , Criança , Humanos , Lactente , Recém-Nascido , Alumínio/análise , Arsênio/análise , Arsênio/toxicidade , Brasil/epidemiologia , Cádmio/análise , Carcinógenos/análise , Carcinógenos/toxicidade , Saúde da Criança , Contaminação de Alimentos/análise , Intoxicação por Metais Pesados , Fórmulas Infantis/análise , Mercúrio/análise , Metaloides/análise , Metais Pesados/análise , Receptores de Antígenos de Linfócitos T , Medição de Risco , Estanho/análise , Urânio/análise
13.
Environ Monit Assess ; 194(11): 807, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36123411

RESUMO

Organic and inorganic nitrogen ions in the environment play important role across environmental matrices. Rainwater samples collected from ambient and different roofing surfaces (zinc, aluminium, asbestos and stone-coated roofing sheets) from selected locations at Ogale, Rumuodomaya/Rumuodome, Diobu and Chokocho within Rivers State, Niger Delta, Nigeria, from April to June, July to August and September to October depicting three regiments of early, mid and late rains. The samples were analysed for Kjeldahl nitrogen, ammonium, nitrate and nitrite using APHA methodology. Quantitative assessment showed that Kjeldahl nitrogen were in range of 0.11 to 28.05 mg/L; ammonium 0.50 to 20.22 mg/L, nitrate from 0.12 to 22.69 mg/L and nitrite from 0.15 to 3.90 mg/L. Parameters decreased from early to late rain, which can be attributed to rain dilution factor potential, wind pattern and emission from anthropogenic sources that influenced the rainwater quality across surfaces. Nitrogen results showed that dry and wet deposition has great impact; atmospheric aerosols and biogeochemical interactions can affect water quality. Monthly variation showed that Ogale had high regression compared to other locations due to close proximity to oil and gas emission and marine contribution. Neutralization factor showed that nitrate-nitrite compounds have strong correlation with ammonium ion. Non-carcinogenic risk assessment using US EPA model showed hazard index less than one (1), thus no associated health effect of nitrate and nitrite in rainwater. In conclusion, it is evident that nitrate/nitrite levels and other nitrogen derivatives in rainwater in crude oil-producing Niger Delta and its continuous consumption can cause negative health outcome.


Assuntos
Compostos de Amônio , Petróleo , Aerossóis/análise , Alumínio/análise , Compostos de Amônio/análise , Quimiometria , Monitoramento Ambiental/métodos , Nigéria , Nitratos/análise , Nitritos/análise , Nitrogênio/análise , Óxidos de Nitrogênio/análise , Compostos Orgânicos , Petróleo/análise , Medição de Risco , Zinco/análise
14.
Chemosphere ; 307(Pt 4): 135799, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35931251

RESUMO

The morphology and metal oxidation states of atmospheric aerosols are pertinent to their formation processes and ensuing interactions with surrounding gases, vapors and other environments upon deposition, such as human respiratory tract, soil and water. Although much progress has been made in recent years through single-particle techniques, considerably less is known with respect to the three-dimensional (3D) internal morphology of single atmospheric aerosol particles due to the limited penetration depth of electron microscopy. In this study, for the first time, a novel synchrotron-based transmission X-ray microscopy (TXM) methodology has been developed to visualize the 3D internal chemical mixing state and structure of single particles. The results show that the TXM is more applicable to the imaging of solid particles containing high-density elements, e.g., iron (Fe), aluminum (Al), silicone (Si), carbon (C) and sulfur (S), and/or solid particles of sizes larger than about 100 nm. In addition, the TXM is capable to reveal the fine 3D topographic features of single particles. The derived 3D internal and external information would be difficult to discern in the 2D images from electron microscopy. The TXM 3D images illustrate that aerosol particles exhibit complex internal mixing state and structure, e.g., homogeneously-, heterogeneously-mixed, multiple inclusions, fibrous, porous, and core-shell configuration. When coupled with the synchrotron-based X-ray fluorescence spectrometry (XRF) and absorption near-edge spectroscopy (XANES) of an X-ray nanoprobe in the energy range of 4-15 keV, the 3D morphology of single particles is further supplemented with the spatial distribution and oxidation sates of selected elements, including Fe, vanadium (V), manganese (Mn), chromium (Cr) and arsenic (As). The presented cross-platform, synchrotron-based methodology shows promise in complementing existing single-particle techniques and providing new insights to the heterogeneity of single-particle micro-physicochemical states relevant to the aerosol chemistry, optical properties, and their environmental and health impacts.


Assuntos
Arsênio , Manganês , Aerossóis/análise , Alumínio/análise , Carbono , Cromo/análise , Gases/análise , Humanos , Ferro/química , Manganês/análise , Silicones , Solo , Enxofre , Síncrotrons , Vanádio/análise , Água/análise
15.
Environ Sci Process Impacts ; 24(1): 89-101, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-34904604

RESUMO

Phosphorus (P) is one of the key limiting nutrients for algal growth in most fresh surface waters. Understanding the determinants of P accumulation in the water column of lakes of interest, and the prediction of its concentration is important to water quality managers and other stakeholders. We hypothesized that lake physicochemical, climate, and watershed land-use attributes control lake P concentration. We collected relevant data from 126 lakes in Maine, USA, to determine the major drivers for summer total epilimnetic P concentrations. Predictive regression-based models featured lake external and internal drivers. The most important land-use driver was the extent of agriculture in the watershed. Lake average depth was the most important physical driver, with shallow lakes being most susceptible to high P concentrations; shallow lakes often stratify weakly and are most subject to internal mixing. The sediment NaOH-extracted aluminum (Al) to bicarbonate/dithionite-extracted P molar ratio was the most important sediment chemical driver; lakes with a high hypolimnetic P release have low ratios. The dissolved organic carbon (DOC) concentration was an important water column chemical driver; lakes having a high DOC concentration generally had higher epilimnetic P concentrations. Precipitation and temperature, two important climate/weather variables, were not significant drivers of epilimnetic P in the predictive models. Because lake depth and sediment quality are fixed in the short-term, the modeling framework serves as a quantitative lake management tool for stakeholders to assess the vulnerability of individual lakes to watershed development, particularly agriculture. The model also enables decisions for sustainable development in the watershed and lake remediation if sediment quality is conducive to internal P release. The findings of this study may be applied to bloom metrics more directly to support lake and watershed management actions.


Assuntos
Lagos , Fósforo , Alumínio/análise , Matéria Orgânica Dissolvida , Fósforo/análise , Qualidade da Água
16.
J Complement Integr Med ; 19(2): 233-242, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34957732

RESUMO

OBJECTIVES: In alternative medicine, plants pay a major role. Some plants are known for their poisonous nature but still have some importance in the herbal drug industry for their medicinal value. Strychnos nux-vomica is one such plant. Its nuts are called as poison nut due to the presence of alkaloids. Both the nut and its minerals are having medicinal properties and hence the present study was indented to understand the nature of primary metabolites and multi elemental composition. METHODS: The nuts of S. nux-vomica were procured, authenticated, powdered and subjected to proximate analysis parameters, visualization of thin layer chromatographic separation (TLC) and finger print profiling through high performance thin layer chromatographic (HPTLC); surface morphology by scanning electron microscopy, energy dispersive X-ray analysis, X-ray fluorescence spectrometry, X-ray photoelectron spectrometry, powder X-ray diffractometry and inductively coupled plasma optical emission spectrometry. RESULTS: In HPTLC, 7 spots each under 254 nm, 366 nm, derivatization with vanillin sulphuric acid (VSR) reagent appeared and 2 spots with Dragendorff's reagent. In HPTLC, 12 peaks at 254 nm, 9 peaks at 366 nm, 7 peaks at 520 nm after derivatization with VSR reagent detected. Elements such as potassium, calcium, magnesium, chlorine, aluminium, iron, manganese, sodium, nickel, phosphorus, copper, zinc, sulphur and silicon were identified. PXRD revealed that the presence of potassium chloride, calcite and dolomite as major elemental composition. CONCLUSIONS: The presence of all the above elements has vital roles on human physiology. Potassium, calcium, chlorine, aluminium, nickel, phosphorus, sulphur and silicon are reported for the first time in this study.


Assuntos
Strychnos nux-vomica , Alumínio/análise , Cálcio , Cloro , Humanos , Níquel , Nozes , Fósforo/análise , Potássio , Sementes/química , Silício/análise , Análise Espectral , Strychnos nux-vomica/química , Enxofre/análise
17.
Int J Mol Sci ; 22(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34681960

RESUMO

Effects of Al content on the formation and the photoluminescence properties of CaAlSiN3:Eu2+ phosphor (CASIN) were investigated by a combustion synthesis method. XRD (X-ray diffraction), combined with PL (photoluminescence), TEM-EDS (transmission electron microscope equipped with an energy-dispersive X-ray spectroscope), and SAED (selected area electron diffraction) measurements, show that the bar-like CASIN gives a stronger emission than the plate-like and agglomerated fine particles. The emission intensity increases as the Al content increased from Al = 0.2 to Al = 0.8, which resulted from the extent of formation of CASIN increases. Then, the emission intensity decreases as the Al content is increased from Al = 0.8 to Al = 1.5, which resulted from the transformation of morphology of CASIN and a large amount formation of AlN. In addition, the extent of formation of CASIN increases with increasing Al from Al = 0.2 to Al = 1.2 and begins to decrease as Al is further increased to 1.5, and thus the peak emission wavelength increases from 647 nm to 658 nm as the Al molar ratio is increased from 0.2 to 1.2 and begins to decrease when further increasing the Al molar ratio to 1.5, which resulted from the large amount of AlN formed.


Assuntos
Alumínio/metabolismo , Cálcio/química , Carbazóis/química , Európio/química , Luminescência , Substâncias Luminescentes/química , Fósforo/química , Alumínio/análise
18.
Mol Nutr Food Res ; 65(15): e2100345, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34061440

RESUMO

SCOPE: Boron is a trace element that naturally occurs in soil, making mineral and medicinal water important contributors to overall intake. Thus, in a systematic screening, the mean boron concentrations of 381 German mineral and medicinal waters are determined. METHODS AND RESULTS: Boron concentrations in mineral and medicinal waters are analyzed by inductively coupled mass spectrometry (ICP-MS). Highest boron values find in waters from the southwest of Germany. The boron content of the waters is positively correlated with the concentration of most other analyzed bulk elements, including calcium, potassium, magnesium, and sodium. Mineral waters with either low (7.9 µg L-1 ), medium (113.9 µg L-1 ), or high (2193.3 µg L-1 ) boron content are chosen for boron exposure experiments in fruit flies (Drosophila melanogaster) and humans. In flies, boron-rich mineral water significantly increases boron accumulation, with the accumulation predominantly occurring in the exoskeleton. In humans, serum boron and 24-h urinary boron excretion significantly increase only in response to the intake of boron-rich mineral water. CONCLUSION: Overall, the current data demonstrate that mineral and medicinal waters vary substantially in the content of boron and that boron-rich mineral water can be used to elevate the boron status, both in flies and humans.


Assuntos
Boro/análise , Boro/farmacocinética , Drosophila melanogaster/efeitos dos fármacos , Água Doce/análise , Águas Minerais/análise , Adulto , Alumínio/análise , Animais , Disponibilidade Biológica , Boro/sangue , Boro/urina , Suplementos Nutricionais , Água Doce/química , Alemanha , Voluntários Saudáveis , Humanos , Lítio/análise , Masculino , Oligoelementos/análise
19.
Chem Biodivers ; 18(8): e2100257, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34101363

RESUMO

Allophylus edulis (A. St.-Hil., A. Juss. & Cambess.) Radlk. (Sapindaceae) is an edible plant from the South American biodiversity that is a potential source of bioactive compounds. The mineral content and antioxidant activity of Allophylus edulis leaves were investigated, as well as the composition and the antioxidant activity of the essential oil. The mineral content was determined by ICP - OES and the antioxidant assays were assessed by ABTS, DPPH and FRAP. The essential oil was obtained by hydrodistillation and analyzed by GC/MS. Calcium, potassium, phosphorus, sulfur, and magnesium were the main minerals found in A. edulis leaves. Of the toxic metals that were present, a low level of aluminum was detected. The essential oil of A. edulis has (E)-nerolidol as major compound and both, the leaves, and the essential oil isolated from the leaves have antioxidant potential. These findings could provide a framework for developing new food and non-food products with A. edulis leaves.


Assuntos
Antioxidantes/química , Minerais/química , Óleos Voláteis/química , Sapindaceae/química , Alumínio/análise , Biodiversidade , Produtos Biológicos/química , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Sapindaceae/metabolismo , Sesquiterpenos/análise , América do Sul
20.
J Sci Food Agric ; 101(11): 4523-4531, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33454954

RESUMO

BACKGROUND: Phosphorus (P) is an essential mineral nutrient for crop growth and development. Much remains unknown regarding the content and distribution of P forms in different soil aggregates as affected by tillage practices. A 3-year field experiment was conducted to investigate the effects of no-tillage (NT), rotary tillage (RT), subsoiling (SS), and deep tillage (DT) on soil aggregate distribution pattern, aggregate-associated P content, and to understand the conversion trend. RESULTS: Tillage has the potential to accelerate the processes in transforming macro-aggregates (> 0.25 mm) into micro-aggregates (< 0.25 mm). Greatest aggregate stability was attained under RT. Total phosphorus (TP) and available phosphorus (AP) under NT were increased by 21.1-82.0% in contrast to other tillage treatments. The NT had high content in inorganic phosphorus (IP), aluminum phosphorus (Al-P), and iron phosphorus (Fe-P) with 416.7, 107.9, and 99.1 mg·kg-1 on average, respectively. Aggregates with a size dimension of < 2 mm were more sensitive than other sizes of aggregates. IP was evenly distributed throughout all aggregates, ranging from 336.3 to 430.6 mg kg-1 . No differences in organic phosphorus (OP) were found in all tillage treatments, while NT promoted the transformation of labile OP to IP. The AP and OP were generally more abundant in aggregates of 2 to 0.25 mm and < 0.25 mm. CONCLUSION: Short-term NT can improve soil structure and increase P reserves, thus, enhancing the conversion of P from being scarce to available. © 2021 Society of Chemical Industry.


Assuntos
Agricultura/métodos , Fósforo/análise , Solo/química , Alumínio/análise , China , Fertilizantes/análise
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