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1.
Food Chem ; 452: 139434, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38733680

RESUMEN

Arthrospira (Limnospira) maxima (A. maxima) and Chlorella vulgaris (Ch. vulgaris) are among the approved microalgae and cyanobacteria (MaC) in the food industry that are known to be safe for consumption. However, both organisms are controversial regarding their vitamin B12 content, due to the possible occurrence of pseudo-cobalamin. Concurrently, their nutrition profiles remain understudied. The main purpose of the present study was to identify their nutrition profiles, focusing mainly on vitamin B12, amino acids, and micronutrients under iron-induced hormesis (10 mg/L Fe in treated samples). Our findings indicate a higher B12 content in A. maxima compared to Ch. vulgaris (both control and treated samples). Using liquid chromatography with tandem mass spectrometry (LC-MS/MS), the cyanocobalamin content was determined as 0.42 ± 0.09 µg/g dried weight (DW) in the A. maxima control and 0.55 ± 0.02 µg/g DW in treated A. maxima, resulting in an insignificant difference. In addition, the iron-enriched medium increased the amount of iron in both tested biomasses (p < 0.01). However, a more pronounced (approximately 100×) boost was observed in Ch. vulgaris, indicating a better absorption capacity (control Ch. vulgaris 0.16 ± 0.01 mg/g Fe, treated Ch. vulgaris 15.40 ± 0.34 mg/g Fe). Additionally, Ch. vulgaris also showed a higher micronutrient content. Using both tested microalgae, meeting the sufficient recommended daily mineral allowance for an adult is possible. By combining biomass from A. maxima and Ch. vulgaris in a ratio of 6:1, we can fulfill the recommended daily allowance of vitamin B12 and iron by consuming 6 tablets/6 g. Importantly, iron hormesis stimulated amino acid composition in both organisms. The profile of amino acids may suggest these biomasses as promising potential nutrition sources.


Asunto(s)
Aminoácidos , Chlorella vulgaris , Micronutrientes , Spirulina , Vitamina B 12 , Chlorella vulgaris/química , Chlorella vulgaris/metabolismo , Chlorella vulgaris/crecimiento & desarrollo , Vitamina B 12/metabolismo , Vitamina B 12/análisis , Micronutrientes/análisis , Micronutrientes/metabolismo , Aminoácidos/metabolismo , Aminoácidos/análisis , Spirulina/química , Spirulina/metabolismo , Valor Nutritivo , Microalgas/química , Microalgas/metabolismo , Microalgas/crecimiento & desarrollo , Espectrometría de Masas en Tándem , Hierro/metabolismo , Hierro/análisis
2.
Ecotoxicol Environ Saf ; 270: 115823, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38176180

RESUMEN

Two-dimensional materials have recently gained significant awareness. A representative of such materials, black phosphorous (BP), earned attention based on its comprehensive application potential. The presented study focuses on the mode of cellular response underlying the BP interaction with Chlamydomonas reinhardtii as an algal model organism. We observed noticeable ROS formation and changes in outer cellular topology after 72 h of incubation at 5 mg/L BP. Transcriptome profiling was employed to examine C. reinhardtii response after exposure to 25 mg/L BP for a deeper understanding of the associated processes. The RNA sequencing has revealed a comprehensive response with abundant transcript downregulation. The mode of action was attributed to cell wall disruption, ROS elevation, and chloroplast disturbance. Besides many other dysregulated genes, the cell response involved the downregulation of GH9 and gametolysin within a cell wall, pointing to a shift to discrete manipulation with resources. The response also included altered expression of the PRDA1 gene associated with redox governance in chloroplasts implying ROS disharmony. Altered expression of the Cre-miR906-3p, Cre-miR910, and Cre-miR914 pointed to those as potential markers in stress response studies.


Asunto(s)
Chlamydomonas reinhardtii , Chlamydomonas reinhardtii/metabolismo , Transcriptoma , Fósforo/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Comprensión , Cloroplastos/genética , Cloroplastos/metabolismo
3.
Sci Total Environ ; 851(Pt 2): 157984, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-35987235

RESUMEN

The distribution and geochemistry of arsenic (As) in water and sediments of the Zenne River, a small urban river flowing through Brussels (Belgium), were assessed based on the results of 18 sampling campaigns performed between 2010 and 2021. In general, concentrations of As sharply increase between Vilvoorde and Eppegem and are up to 6-8 times higher in the section downstream of Eppegem in comparison to the upstream part of the Zenne. The monitoring surveys in which the grab water samples were taken at a 1-hour sampling frequency revealed that the large temporal variability in As concentrations found in the downstream part of the river is driven by the tidal cycle. The diffusive gradients in thin films (DGT) technique was used to assess the DGT labile As species in surface water and sediment porewater. Three DGT sorbents (Metsorb, Lewatit FO 36, and ZrO2) for the determination of total As were applied to compare their performance, and the 3-mercaptopropyl-functionalized silica (3-MFS) was used for the speciation of As(III) in porewater. Arsenic species are fully labile in surface waters as the DGT time-integrated concentrations of As were in good agreement with the average concentrations calculated from the grab samplings. In sediment porewaters, As is predominantly present as non-DGT labile species (66-93 %), and the DGT labile As fraction is dominated by As(III). Flux calculations evaluating the relative importance of different As sources to the Zenne River revealed the presence of a point source on the tributary Tangebeek, which contributes to 87 % of the As load carried by the Zenne River.


Asunto(s)
Arsénico , Contaminantes Químicos del Agua , Arsénico/análisis , Monitoreo del Ambiente/métodos , Disponibilidad Biológica , Contaminantes Químicos del Agua/análisis , Bélgica , Agua , Dióxido de Silicio , Sedimentos Geológicos
4.
Environ Sci Pollut Res Int ; 29(40): 61383-61396, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35445304

RESUMEN

The distribution of mercury species was studied in all aquatic ecosystem components (i.e., water, sediment, emergent aquatic plants, invertebrates and omnivorous and piscivorous fish) of the Záskalská water reservoir (Central Bohemia, Czech Republic) which is in the vicinity of an abandoned cinnabar mine. The results indicate that the transport of mercury from the cinnabar mine is the major source of mercury in the Záskalská reservoir. The legal maximum limit (0.07 µg/L) for total mercury concentration in water samples was exceeded only during rainy periods. The total mercury concentration in the surface sediments was in the range from 0.22 to 9.19 mg/kg in dry matter (up to 0.2% CH3Hg+) and was sample site-specific. The dominant form of mercury in sediments was mercury sulphide (22.9-79.2%). The emergent macrophytes accumulated mercury primarily by the roots from sediments, and no significant translocation of mercury to leaves was observed. The legal maximum limit for mercury content in fish muscle (0.5 mg/kg in the fresh matter) was exceeded up to 4.48 times for piscivorous fish. Hazard index values indicate a health risk concern for children and for people consuming more than 100 g of fish muscle per day. Our results emphasise the need to implement legal restrictions on the consumption of piscivorous fish caught in ecosystems downstream of abandoned cinnabar mines.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Animales , República Checa , Ecosistema , Monitoreo del Ambiente , Peces , Agua Dulce , Humanos , Mercurio/análisis , Compuestos de Mercurio , Agua , Contaminantes Químicos del Agua/análisis
5.
Chemosphere ; 288(Pt 2): 132545, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34648791

RESUMEN

The ability of submerged aquatic plants (Elodea canadensis, Myriophyllum spicatum, Ceratophyllum demersum) and a natant plant (Eichhornia crassipes) to bioaccumulate mercury was evaluated in a laboratory experiment as well as in a real aquatic ecosystem situated in the vicinity of a cinnabar mine. Moreover, the ability of the diffusive gradients in the thin films technique (DGT) to predict mercury bioavailability for selected aquatic plants was tested. The submerged plants had sufficient bioaccumulation capacity for long-term phytoaccumulation of mercury in a real aquatic ecosystem. The determined bioaccumulation factor was greater than 1000. On average, the submerged plant leaves accumulated 13 times more mercury than the leaves of the natant aquatic plants. Chlorides at concentrations up to 200 mg/L had no statistically significant effect on mercury accumulation, nevertheless, the presence of humic acid in the water environment resulted in its significant (p < 0.002) decrease. A strong positive correlation (r > 0.66) was determined between mercury concentration in the input parts (leaves and/or roots) of the aquatic plants and the flow of mercury into DGT units.


Asunto(s)
Mercurio , Disponibilidad Biológica , Ecosistema , Compuestos de Mercurio
6.
Talanta ; 240: 123168, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34954614

RESUMEN

Monitoring of uranium in the environment using the Diffusive Gradients in Thin-films (DGT) technique gains in importance as it can provide unique information about the bioavailability of the element and allows its long-term in-situ measurement. Hence, in this study, four DGT binding phases (Chelex-100, Dow-PIWBA, Diphonix, and Lewatit FO 36 resins) were evaluated for uranium monitoring to assess the robustness of their performance in estuarine and marine environments. These DGTs were deployed along the Scheldt estuary (Belgium and the Netherlands) over four campaigns between 2014 and 2021. The DGT performance (ratio of the DGT-determined vs. dissolved U concentration in grab water sample) varied with the water salinity. The Chelex-100 DGTs generally provided good performance in freshwater (median ratios close to 1.0), but an inverse correlation with the increasing salinity was observed (median ratios 0.7 at the stations with salinity >5). The Lewatit FO 36 DGTs provided good performance in the salinity range 0-18 (median ratios 1.0). However, a strong negative influence was observed at stations with high salinity levels (>18, ratio 0.6) and during the long-term deployment in seawater (ratios <0.5 over deployment periods ≥2 days). The Dow-PIWBA and Diphonix DGTs provided overall similar results with excellent performances along the whole salinity gradient (median ratios 1.1 and 1.0, respectively). Nevertheless, the long-term deployment trial in seawater (salinity ∼27) revealed the robustness of Diphonix DGTs that provided outstanding results even after 28 days of deployment (ratio 1.0). The differences in the performance of tested DGT resins were mostly given by the changes of U speciation along the salinity gradient. The speciation modelling of U showed that calcium uranyl carbonate complexes dominate along the Scheldt estuary (from 97 to 86% seawards) with increasing fraction of UO2(CO3)34- (from 2 to 14%) towards the mouth.


Asunto(s)
Uranio , Contaminantes Químicos del Agua , Difusión , Monitoreo del Ambiente , Estuarios , Geles , Poliestirenos , Polivinilos , Salinidad , Uranio/análisis , Contaminantes Químicos del Agua/análisis
7.
Sci Rep ; 11(1): 17125, 2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34429471

RESUMEN

The intensive use of insecticides in global agricultural production has attracted much attention due to its many adverse effects on human health and the environment. In recent years, the utilization of nanotechnology has emerged as a tool to overcome these adverse effects. The aim of this work was to test different microparticles (zinc oxide (ZnO MPs) and silicon dioxide microparticles (SiO2 MPs)), and silver nanoparticles (Ag NPs) and to study their toxicity on a model organism, Tenebrio molitor. A comprehensive comparative study, which included more than a thousand mealworms divided into nine separate groups, was conducted. In addition to pure nano/microparticle solutions, the effect of particles mixed with the microalgae extract Chlamydomonas reinhardtii was also observed. Pure Ag NPs and SiO2 MPs resulted in larval mortality of more than 70% compared to that of pure ZnO MPs, in which the mortality rate was approximately 33%. A mixture of the algal extract with zinc oxide microparticles resulted in mortality that was double compared to that observed with pure ZnO MPs. In parallel, atomic absorption spectrometry (AAS) was used to determine the difference in the concentration of trace elements in the bodies of dead and live larvae.


Asunto(s)
Chlamydomonas reinhardtii/química , Insecticidas/toxicidad , Nanopartículas del Metal/química , Extractos Vegetales/química , Tenebrio/efectos de los fármacos , Animales , Insecticidas/química , Plata/química , Zinc/química
8.
Environ Pollut ; 283: 117092, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33892369

RESUMEN

Knowledge of the concentration of the bioavailable forms of mercury in the soil is necessary, especially, if these soils contain above-limit total mercury concentrations. The bioavailability of mercury in soil samples collected from the vicinity of abandoned cinnabar mines was evaluated using diffusive gradients in the thin films technique (DGT) and mercury phytoaccumulation by vegetables (lettuce, spinach, radish, beetroot, carrot, and green peas). Mercury was accumulated primarily in roots of vegetables. The phytoaccumulation of mercury into edible plant parts was site-specific as well as vegetable species-specific. The mercury concentration in edible parts decreased in the order: spinach leaf ≥ lettuce leaf ≥ carrot storage root ≥ beetroot storage root > radish storage root > pea legume. The translocation index as well as the target hazard quotient indicate the possible usability of soils from the vicinity of abandoned cinnabar mines for planting pod vegetables (peas). A strong positive correlation (r = 0.75 to 0.92, n > 30, p < 0.05) was observed between mercury concentration in secondary roots, the storage roots, leaves of vegetables and the flux of mercury from soil to the DGT units, and the effective concentration of mercury in soil solutions.


Asunto(s)
Mercurio , Contaminantes del Suelo , Disponibilidad Biológica , Mercurio/análisis , Compuestos de Mercurio , Suelo , Contaminantes del Suelo/análisis , Verduras
9.
Talanta ; 228: 122234, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33773713

RESUMEN

The sorption ability of Lewatit FO 36-DGT resin gel, which has been developed for arsenic determination, towards uranium was tested by batch experiments within this study for the first time. Since the uptake efficiency of uranium was 99.0 ± 0.4% and the maximum uptake capacity was not achieved even at the U spike of 1250 µg in the solution, the Lewatit FO 36 resin seems to be a suitable binding phase for DGT resin gels for the determination of uranium. The resin gel also does not display any significant sorption selectivity in favour of one element over another. A novel protocol for simultaneous elution of arsenic and uranium from Lewatit FO 36 resin gel was therefore proposed in this study. The elution efficiencies of 90.3 ± 3.9% and 85.2 ± 3.1% for As and U, respectively, were obtained using 5 mL of 1 M NaOH at 70 °C for 24 h. The comparison with the original elution protocol using microwave-assisted elution by 0.25 M NaOH and 0.17 M NaCl at 130 °C for 16 min indicates, that the novel elution protocol provides good results in the performance of arsenic elution and, in addition, allows simultaneous elution of uranium. Moreover, the elimination of NaCl from the elution process allows a fast and simple analysis of both elements using ICP-MS, and therefore, the Lewatit FO 36-DGT technique can become more commonplace among laboratories without the need to modify the analytical method as proposed in the original study.

10.
Toxics ; 9(2)2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33546233

RESUMEN

Selenium nanoparticles (SeNPs) are fast becoming a key instrument in several applications such as medicine or nutrition. Questions have been raised about the safety of their use. Male rats were fed for 28 days on a monodiet containing 0.5, 1.5, 3.0 and 5.0 mg Se/kg. Se content in blood and liver, liver panel tests, blood glucose, total antioxidant capacity (TAC), the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were analysed. Liver and duodenum were subjected to histopathology examination. The weight gain of rats showed no differences between tested groups. Se content in blood was higher in all treated groups compared to the control group. The liver concentration of Se in the treated groups varied in the range from 222 to 238 ng/g. No differences were observed in the activity of AST (aspartate aminotransferase), ALP (alkaline phosphatase) and TAS (total antioxidant status). A significant decrease in ALT activity compared to the control group was observed in the treated groups. GPx activity varied from 80 to 88 U/mL through tested groups. SOD activity in liver was decreased in the SeNP-treated group with 5 mg Se/kg (929 ± 103 U/mL). Histopathological examination showed damage to the liver parenchyma and intestinal epithelium in a dose-dependent manner. This study suggests that short-term SeNP supplementation can be safe and beneficial in Se deficiency or specific treatment.

11.
Environ Toxicol Chem ; 39(9): 1670-1677, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32516439

RESUMEN

Knowledge of the fractionation of mercury in soils in the vicinity of abandoned cinnabar mines is essential for assessing the usability of soils for the cultivation of agriculturally important crops. Two different sequential extraction methods and the technique of diffusive gradients in thin films (DGT) were applied and compared for fractionation of mercury in soils from mercury-contaminated sites intended for farming purposes. The mercury found in these soils was primarily in the form of mercury sulfide (58.6-83.9%), followed by 6.7 to 15.4% of organically bound mercury and 2.9 to 23.2% of elemental mercury. Up to 10.3% of labile mercury species were determined by both sequential extraction methods in these soils. However, only 0.01 to 0.13% of mercury was determined as a bioavailable fraction using the DGT technique. Both sequential extraction methods tested for the fractionation analysis of mercury in contaminated soils were in excellent agreement. The content of the mobile (labile) mercury determined by the sequential extraction methods was statistically significantly higher (p < 0.0001) than the content of bioavailable mercury determined by the DGT technique. Environ Toxicol Chem 2020;39:1670-1677. © 2020 SETAC.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminantes del Suelo/análisis , Suelo/química , Disponibilidad Biológica , Fraccionamiento Químico , Difusión , Mercurio/análisis , Soluciones
12.
Anal Chim Acta ; 1102: 36-45, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32043994

RESUMEN

An ion-exchange resin Lewatit FO 36 was used for the preparation of a new resin gel for the diffusive gradient in thin films technique (DGT). The DGT method was optimized for the accumulation of four bioavailable arsenic species (AsIII, AsV, monomethylarsonic acid, dimethylarsinic acid) in the aquatic environment. The total sorption capacity of Lewatit FO 36 resin gel was 535 µg As disc-1. The microwave-assisted extraction in the presence of NaCl (10 g L-1) and NaOH (10 g L-1) was used for the isolation of arsenic species from the Lewatit FO 36 resin gel. The elution efficiency of arsenic was 98.4 ± 2.0%. Arsenic was determined by the optimized electrothermal atomic absorption spectrometry (ET-AAS) method using palladium modifier, pre-atomization cool-down step and tungsten carbides coating of graphite tube. The Lewatit FO 36 resin gel provides accurate results (cDGT/cSOL ratio 0.86-1.00) in the pH range 4-8. No significant influence of experimental conditions was observed in the presence of chlorides (0-0.5 mol L-1) and humic acid (0-100 mg L-1). Only a very high concentration of phosphates (10 mg L-1) caused a slight decrease in the diffusion coefficients of MMA and AsV species (8.4% and 12.4%, respectively). The presence of iron (0-1 mg L-1) caused a decrease in the diffusion coefficients, but with regard to the common concentrations of iron (less than 0.3 mg L-1), the negative effect was considered not significant for AsIII and DMA in natural water. The DGT-ET-AAS method was applied for the determination of bioavailable arsenic species in the spiked river water samples and also in-situ in the water reservoir. The new resin gel was characterized by a homogeneous gel structure with excellent reproducibility (< 5% variation of results between batches) and high sorption capacity which suggests its possible long-term application (up to 286 days in the environment with the arsenic concentration of 100 µg L-1).

13.
Chemosphere ; 234: 373-378, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31228839

RESUMEN

The diffusive gradients in thin films technique (DGT) was used for the determination of bioavailable mercury in urban soils, and results were compared to the mercury accumulation by Pisum sativum L. (pea) parts (leaf, root, stem, blossom, legume, and green seed). The total mercury concentration in soil samples was ranged between 0.084 and 0.326 mg kg-1. The soil solutions contained 0.15%-0.20% of mercury present in soils. In the soil solution, 2.21%-3.45% of mercury was available for DGT units. The highest mercury content was determined in the leaf and root of the pea plant, and the lowest in the consumable part of the pea plant (green seed). Mercury concentration in the parts of the pea plant increased over time, alongside the growth of the plant. The effect of acid precipitation on mercury bioavailability was statistically non-significant (p = 0.53). Significant and positive correlations were found between mercury flux into DGT unit, and mercury flux into the root (r = 0.989), leaf (r = 0.985), and stem (r = 0.904) of the pea plant. The obtained results suggest that the DGT method could be used for description of the uptake of mercury by pea plant parts in non-contaminated and slightly contaminated soils.


Asunto(s)
Mercurio/farmacocinética , Pisum sativum/metabolismo , Suelo/química , Disponibilidad Biológica , Mercurio/análisis , Métodos , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Semillas/metabolismo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/farmacocinética
14.
Environ Toxicol Chem ; 38(2): 321-328, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30620786

RESUMEN

We assessed the relationship between the diffusive gradient in thin film (DGT) technique using the new ion-exchange resin Ambersep GT74 and the uptake of mercury (Hg) by a model plant cultivated on metal-contaminated agricultural soils under greenhouse conditions. Based on the total Hg content, 0.37 to 1.17% of the Hg passed to the soil porewater from the solid phase, and 2.18 to 9.18% of the Hg is DGT-available. These results were confirmed by calculating the R value (the ratio of the concentrations of bioavailable Hg measured by DGT and soil solution), which illustrated the strong bonding of Hg to the solid phase of soil and its extremely low mobility. Only inorganic Hg2+ species were found in the metal-contaminated agricultural soils, as determined by a high-performance liquid chromatography-cold vapor atomic fluorescence spectrometry speciation analysis. The Hg was distributed in Miscanthus × giganteus organs in the following order for all sampling sites: roots (55-82%) >> leaves (8-27%) > stems (7-16%) > rhizomes (4-7%). Environ Toxicol Chem 2019;38:321-328. © 2018 SETAC.


Asunto(s)
Monitoreo del Ambiente/métodos , Mercurio/análisis , Poaceae/metabolismo , Contaminantes del Suelo/análisis , Suelo/química , Disponibilidad Biológica , Transporte Biológico , Cromatografía Líquida de Alta Presión , Resinas de Intercambio Iónico/química , Mercurio/metabolismo , Modelos Biológicos , Contaminantes del Suelo/metabolismo
15.
Chemosphere ; 211: 1109-1112, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30223326

RESUMEN

The ability of the DGT technique to predict Hg2+ bioavailability for input tissues (skin, gills, and scales) of common carp in the presence of chloride ions and humic acid (HA) was evaluated. The mercury accumulation by the DGT units and input tissues of carp decreased with an increasing concentration of chloride ions (29-180 mg L-1) and HA (0-5 mg L-1). In the presence of chloride ions and HA, statistically significant correlations (Pearson's correlation coefficients 0.731-0.954) were determined between the rate of mercury accumulation by input tissues of carp and the rate of mercury accumulation by the DGT units. The laboratory experiments suggest the possibility of using the DGT technique for predicting the mercury bioaccumulation in natural aquatic ecosystems instead of commonly used input tissues of fish.


Asunto(s)
Carpas/metabolismo , Cloruros/análisis , Sustancias Húmicas/análisis , Mercurio/farmacocinética , Escamas de Animales/química , Animales , Disponibilidad Biológica , Ecosistema , Branquias/química , Mercurio/análisis , Métodos , Piel/química , Contaminantes Químicos del Agua/análisis
16.
Chemosphere ; 187: 181-187, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28846974

RESUMEN

The mercury bioaccumulation by common carp (Cyprinus carpio L.) tissues (gills, skin, eyes, scales, muscle, brain, kidneys, liver, and spleen) and the capability of the diffusive gradient in thin film (DGT) technique to predict bioavailability of mercury for individual carp's tissues were evaluated. Carp and DGT units were exposed to increasing concentrations of mercury (Hg2+: 0 µg L-1, 0.5 µg L-1, 1.5 µg L-1 and 3.0 µg L-1) in fish tanks for 14 days. In the uncontaminated fish group, the highest mercury concentration was determined in the muscle tissues and, in fish groups exposed to mercury, the highest mercury concentration was determined in the detoxification (kidneys) and input (gills) organs. A strong and positive correlation between the rate of mercury uptake by the DGT technique and the rate of mercury accumulation by fish tissues (gills, skin, scales, and eyes) was observed.


Asunto(s)
Carpas/metabolismo , Mercurio/análisis , Mercurio/farmacocinética , Animales , Disponibilidad Biológica , Difusión , Branquias/química , Branquias/metabolismo , Riñón/química , Riñón/metabolismo , Cinética , Músculos/química , Músculos/metabolismo
17.
Chemosphere ; 185: 1011-1018, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28753902

RESUMEN

Heavy metal pollution is an important concern because of its potential to affect human health. This study was conducted to analyze plants growing on a landfill body and in its surroundings to determine their potential for heavy metal accumulation. In addition, the enrichment coefficient (EC) for the plant/soil system was used for determining the environmental contamination from a landfill in terms of heavy metal accumulation. The samples were taken in 2013-2014. Of the analyzed metals, iron achieved the highest values in the samples, i.e. - stalk (103.4-6564.6 mg/kg DM), roots (6563.6-33,036.6 mg/kg DM), leaf (535.1-11,275 mg/kg DM) and soil (12,389-39,381.9 mg/kg DM). The highest concentrations were determined in 2013 for Fe, Mn and Zn. Iron achieved the highest concentrations in the years 2013-2014. Next, EC values were then calculated, with the highest noted for Cd. Cd, as well as Cr, Ni and Zn are accumulated mostly in the leaves, whereas Co, Cu, Fe, Hg, Mn and Pb are accumulated mainly in the roots of T. vulgare.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo , Tanacetum/metabolismo , Contaminación Ambiental , Humanos , Hierro , Metales Pesados/análisis , Raíces de Plantas/química , Suelo , Contaminantes del Suelo/análisis , Instalaciones de Eliminación de Residuos
18.
Anal Chim Acta ; 866: 21-26, 2015 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-25732689

RESUMEN

A diffusive gradient in thin films technique (DGT) was combined with liquid chromatography (LC) and cold vapor atomic fluorescence spectrometry (CV-AFS) for the simultaneous quantification of four mercury species (Hg(2+), CH3Hg(+), C2H5Hg(+), and C6H5Hg(+)). After diffusion through an agarose diffusive layer, the mercury species were accumulated in resin gels containing thiol-functionalized ion-exchange resins (Duolite GT73, and Ambersep GT74). A microwave-assisted extraction (MAE) in the presence of 6M HCl and 5 M HCl (55 °C, 15 min) was used for isolation of mercury species from Ambersep and Duolite resin gels, respectively. The extraction efficiency was higher than 95.0% (RSD 3.5%). The mercury species were separated with a mobile phase containing 6.2% methanol+0.05% 2-mercaptoethanol+0.02 M ammonium acetate with a stepwise increase of methanol content up to 80% in the 16th min on a Zorbax C18 reverse phase column. The LODs of DGT-MAE-LC-CV-AFS method were 38 ng L(-1) for CH3Hg(+), 13 ng L(-1) for Hg(2+), 34 ng L(-1) for C2H5Hg(+) and 30 ng L(-1) for C6H5Hg(+) for 24 h DGT accumulation at 25 °C.

19.
Anal Chim Acta ; 819: 42-8, 2014 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-24636409

RESUMEN

The diffusive gradients in thin films (DGT) technique, utilizing resin gel with ion-exchange resin Duolite GT73 and new ion-exchange resin Ambersep GT74, was investigated for the accumulation of four mercury species (Hg(2+), CH3Hg(+), C2H5Hg(+), C6H5Hg(+)). The diffusion coefficients of mercury species in agarose gel calculated on the basis of Fick's Law were mercury species-specific. The diffusion coefficients of Hg(2+) and CH3Hg(+) at 25 °C (9.07±0.23×10(-6) cm(2) s(-1) and 9.06±0.30×10(-6) cm(2) s(-1), respectively) were very similar, but the diffusion coefficients of C2H5Hg(+) (6.87±0.23×10(-6) cm(2) s(-1)) and C6H5Hg(+) (3.86±0.19×10(-6) cm(2) s(-1)) were significantly lower. Influence of experimental conditions (pH, selected cations, chlorides and humic substance) on mercury species accumulation by DGT was studied. The DGT technique was applied to river water spiked with mercury species.

20.
J Sep Sci ; 36(9-10): 1509-15, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23441059

RESUMEN

The molecularly imprinted SPE directly coupled to RP LC-MS/MS method has been developed and successfully validated for the determination of six hormones in water and sediment samples. The method is based on the use the home-made column filled with a molecularly imprinted sorbent (imprinted against estrogens) that was used under nonaqueous conditions. Thus, its high selectivity could be utilized resulting in low matrix components' coextraction. The method showed excellent recovery (92-105%) and satisfactory sensitivity (LOQs water: 1.9-4.0 ng/L; LOQs sediment: 0.2-0.5 ng/g). The intra- and interprecision for water and sediment was in the range of 4.0-6.0% and 4.4-7.6%, respectively. Finally, 20 water and sediment samples collected from the Svratka river were analyzed. Only estrone was quantified in eight water samples (4.4-7.1 ng/L); no analytes were found in sediment samples.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Sedimentos Geológicos/química , Hormonas/química , Ríos/química , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/química , Automatización , Hormonas/aislamiento & purificación , Impresión Molecular , Polímeros/síntesis química , Polímeros/química , Extracción en Fase Sólida/instrumentación , Contaminantes Químicos del Agua/aislamiento & purificación
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