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1.
Chemosphere ; 352: 141331, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296205

RESUMO

The study is focused on one of the technology-critical elements (TCEs), Pt in the context of distinguishing ionic from metallic forms and assessing sorption capacity of soil. Solid-liquid extraction, cross-comparison of the results of two determination techniques and two decomposition methods enable quantitative determination of the ionic form and, indirectly, NPs in soil and plants. Information about ionic form is obtained after sample digestion with conc. HNO3 and AdSV determination, and total Pt content is determined after digestion using mixture of conc. HNO3 and conc. HCl. The recovery of Pt was in the range 99-110 % for both forms. The mobility (0.43 mol L-1 HAc) of Pt-NPs and Pt (II) was below 1 % even in the presence of citrates (after 2 month incubation). The long-term sorption study indicated that Pt retention (both forms) in the organic soil is related to formation of organic complexes, and the equilibrium is achieved after 2 days. When the soil is enriched in Fe2O3, stronger sorption is observed up to 2 days for both Pt forms (the mobility is 9-14 pp. lower), to finally achieve similar sorption as without modification, reaching 89/90 % for incubation with DI water, and 81/85 % with citrates. The addition of biocarbon/biochar does not play an important role in immobilization of Pt (II) and Pt-NPs.


Assuntos
Poluentes do Solo , Solo , Platina/análise , Poluentes do Solo/análise , Água , Citratos
2.
RSC Adv ; 13(41): 28834-28842, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37790094

RESUMO

The corrosion of the installations carrying high salinity water is particularly important in the case of utility and therapeutic waters, such as natural brine. The analysis of such complex systems is challenging in the context of routine analysis of Fe and Cr. Both elements can be determined by UV-Vis spectrophotometry after only 1 : 100 dilution and liquid-liquid extraction (LODFe = 0.03 mg L-1) or thermal chloride stripping (LODCr = 0.02 mg L-1). The corrosion process was characterized. Electrochemically accelerated corrosion showed uneven decomposition of the steel components - Cr is less easily released to the solution than Fe. Iron comprises 53% of the dissolved part, and Cr comprises 8.6%, while the steel originally contained 62% of Fe and 18% of Cr. During the short-term (one week) contact of the brine with stainless steel, the amounts of Fe and Cr released to the brine were insignificant from the perspective of its therapeutic value.

3.
Int J Phytoremediation ; 24(14): 1475-1490, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35216535

RESUMO

Pollution of the soils with toxic elements is a serious problem all over the world. One of environmentally friendly techniques of their removal is phytoremediation. This paper is a summary of literature data and the results of own studies about the potential of Sinapis alba for bioaccumulation of Tl, As and PGEs, and its usefulness in remediation of polluted environment. S. alba is characterized with low living requirements, BFs ≫ 1 and high TFs, especially for Tl (up to 3). The influence of different forms of studied elements on plants was discussed based on biomass production, morphological changes and the impact on photosynthesis activity. The plants were cultivated in hydroponics and solid media of various composition, for example, in soil supplemented with MnO2, which resulted in BFs lower 6-7 times for leaves, and about 3-4 times for stems, as well as twice lower leaf development. Application of advanced analytical techniques was presented in studies of the detoxification mechanisms, identification of particular chemical forms of the elements and the presence of phytochelatins and their complexes with the investigated elements.Novelty StatementThe paper summarizes both literature and original data on Sinapis alba exposed to such elements as thallium, arsenic and platinum group metals. The influence of different forms of studied elements on white mustard was discussed based on biomass production and morphological changes, as well as the impact on photosynthesis activity. The study covers such aspects as bioaccumulation, phytotoxicity as well as the usefulness of white mustard in remediation of polluted environment.


Assuntos
Sinapis , Poluentes do Solo , Biodegradação Ambiental , Tálio , Poluentes do Solo/análise , Compostos de Manganês , Óxidos , Solo/química , Plantas , Mecanismos de Defesa
4.
Chemosphere ; 279: 130572, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33866099

RESUMO

Honey bees became a frequently studied environmental research object due to the fact that they are considered as indicators of the environmental contamination with metals. Such studies require reliable methods of sample preparation that allow comparison of the results obtained in different laboratories. In this paper, different variants of sample preparation were examined, including washing, milling and mineralization. Determination of total contents of Cd, Pb, Co, Cr, Cu, and Zn was performed using ICP MS. Each procedure of the sample preparation was characterized in terms of repeatability and recovery and the resulting combined standard uncertainty was evaluated. The relative UNC ranges for the treatment procedures examined are: 11-16% (washing, open digestion), 13-14% (open digestion), 13-51% (washing, closed digestion), 12-37% (washing, milling, closed digestion), 13-68% (closed digestion), and 12-51% (milling, closed digestion). In almost all cases the lower limits of these ranges correspond to Zn determinations while the upper limits to Pb. Analytical results of metal determination obtained for samples prepared according to six different procedures do not differ significantly when compared within the expanded uncertainty (±2×u(c¯M)). The procedures were compared statistically using one-factor analysis of variance (ANOVA) and chemometrically on the basis of Principal Component Analysis (PCA), which allowed to demonstrate some general recommendations regarding environmental monitoring for matrices other than honey bees.


Assuntos
Oligoelementos , Animais , Abelhas , Monitoramento Ambiental , Poluição Ambiental , Análise de Componente Principal , Oligoelementos/análise
5.
Chemosphere ; 262: 127699, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32777609

RESUMO

Determination of Pd traces in environmental samples is still a challenging analytical task. The aim of this study was to propose an efficient system (i.e. ion-exchange resin and eluent) for Pd elution from SPE column after the analyte preconcentration. Moreover, the search was focused on solvents that would not interfere voltammetric determination of Pd, as well as ICP-MS analysis. Five ion-exchange sorbents were compared in terms of effective Pd separation from matrix components when using different eluents. The highest recovery (up to 91%) of palladium was obtained for Dowex 1 and ammonium buffer as the eluent. This solution not only provides relatively high palladium elution efficiency but also allows both voltammetric and ICP-MS determinations, without any additional sample preparation. It was proven that the proposed procedure including SPE separation and determination with AdSV and/or ICP-MS could be used for quantitative Pd measurement in environmental samples, such as quartz sand used for the monitoring of Pd emission in the areas of high traffic density.


Assuntos
Paládio/química , Troca Iônica , Resinas de Troca Iônica , Paládio/análise , Quartzo
6.
Anal Chim Acta ; 1076: 48-54, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31203963

RESUMO

The crucial point of this study was to verify the hypothesis that both thallium species are not affected by the procedure of photolysis when it is applied as a method of simplification of sample matrix containing surfactants, and that this method of sample pretreatment leads to reliable results of Tl speciation analysis. It is important especially because of high instability of Tl(III), which makes partial reduction of Tl(III)DTPA complex unavoidable. After conservation of Tl speciation by addition of DTPA the photolysis assisted with nanostructured hierarchically organized film was performed using "solar lamp" (Fe2O3/WO3/Fe2O3 film, pH 6, 380-800 nm). The results imply that under proposed photolysis conditions Tl(I) is not oxidized in the presence of water matrix, SDS nor DTPA. Also, even 100-fold excess of Fe(III) ions over Tl(I) ions does not accelerate the oxidation of Tl(I) to Tl(III), and already 2 h of heterogeneous photolysis allow to limit the interferences caused by SDS and obtain reliable results. The data obtained by anodic stripping voltammetry (ASV) were verified using an inter-method comparison with SEC ICP MS. Moreover, after 2 h irradiation the reduction rate of Tl(III)DTPA standard solution increased only slightly from 2-3% to 4-6%. The presence of river water matrix causes a slightly higher (9%) reduction of the trivalent form. These changes are irrelevant in the context of instability of Tl(III) compounds. This study indicates that "soft decomposition" can be applied in speciation analysis of thallium in water matrix.

7.
Environ Sci Pollut Res Int ; 26(1): 371-380, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30402693

RESUMO

The inspiration for this study was the anxiety of Warsaw beekeepers, who raised the question whether location of hives in large urban agglomerations results in changes in concentrations of xenobiotics, toxic elements, and micronutrients in honey bees. Preliminary studies required elaboration of the research methodology, as the studied object is characterized by a low degree of homogeneity and the method of sample preparation affects obtained results. From many tested approaches, the use of washed and milled abdomens of the bees is recommended. Results obtained for such prepared samples are slightly lower than for whole bees, but their repeatability is higher, which enables easier interpretation of the trends and comparison of different locations. The contents of selected elements (As, Al, Cd, Co, Cr, Cu, Mn, Pb, and Zn) were compared in bees from urban and rural areas. The studies were supported by pesticides analysis. Also, it was checked whether these substances are accumulated on the surface or inside the bee's body. The research indicates the markers of contamination: Al, As, and Cr on the surface and Cd inside the bodies of honey bees. The location of the hives does not influence significantly the content of "toxic," nutrient metals and metalloids in bees (slightly higher levels of As, Al, Pb, and Cd were found in bees from urban areas). In terms of exposure to these elements and pesticides, the large city environment is not harmful for honey bees.


Assuntos
Abelhas/química , Ecossistema , Monitoramento Ambiental , Poluentes Ambientais/análise , Praguicidas/análise , Oligoelementos/análise , Animais , Xenobióticos/análise
8.
Talanta ; 163: 72-77, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27886772

RESUMO

The developed by us electrochemical device for vitamin B2 (VB2; riboflavin) determination, without preconcentration step, in real products exhibits high sensitivity, selectivity, stability and low detection limit compared to those described in the literature. The determination procedure was based on the monitoring of the reduction current signal of VB2 bound with dsDNA anchored to the electrode surface through intermediary - carboxyphenyl layer. The application of such intermediary layer formed during electroreduction of appropriate diazonium salt at CV peak potential guarantees high efficiency of hybridization process and thus fully available places for VB2 interaction. Moreover, such intermediary layer provides good electrical contact, what is very important in the case of electrochemical sensors. The analytical range of work of the proposed VB2 sensor was between 0.08-1µM (30-377µgL-1) of riboflavin concentration. The obtained detection (LOD) and quantification limits (LOQ) were 24±2 and 55±5µgL-1, respectively. The proposed VB2 detection method was used for determination of riboflavin content in commercially available dietary supplements and yolk of hen egg samples. The accuracy of the obtained data was proved using comparison with an independent method (HPLC FLD).


Assuntos
Técnicas Biossensoriais/instrumentação , Eletroquímica/instrumentação , Limite de Detecção , Riboflavina/análise , Animais , Ovos/análise , Riboflavina/química
9.
BMC Plant Biol ; 16(1): 191, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27590049

RESUMO

BACKGROUND: Heavy metal exposure affect plant productivity by interfering, directly and indirectly, with photosynthetic reactions. The toxic effect of heavy metals on photosynthetic reactions has been reported in wide-ranging studies, however there is paucity of data in the literature concerning thallium (Tl) toxicity. Thallium is ubiquitous natural trace element and is considered the most toxic of heavy metals; however, some plant species, such as white mustard (Sinapis alba L.) are able to accumulate thallium at very high concentrations. In this study we identified the main sites of the photosynthetic process inhibited either directly or indirectly by thallium, and elucidated possible detoxification mechanisms in S. alba. RESULTS: We studied the toxicity of thallium in white mustard (S. alba) growing plants and demonstrated that tolerance of plants to thallium (the root test) decreased with the increasing Tl(I) ions concentration in culture media. The root growth of plants exposed to Tl at 100 µg L(-1) for 4 weeks was similar to that in control plants, while in plants grown with Tl at 1,000 µg L(-1) root growth was strongly inhibited. In leaves, toxic effect became gradually visible in response to increasing concentration of Tl (100 - 1,000 µg L(-1)) with discoloration spreading around main vascular bundles of the leaf blade; whereas leaf margins remained green. Subsequent structural analyses using chlorophyll fluorescence, microscopy, and pigment and protein analysis have revealed different effects of varying Tl concentrations on leaf tissue. At lower concentration partial rearrangement of the photosynthetic complexes was observed without significant changes in the chloroplast structure and the pigment and protein levels. At higher concentrations, the decrease of PSI and PSII quantum yields and massive oxidation of pigments was observed in discolored leaf areas, which contained high amount of Tl. Substantial decline of the photosystem core proteins and disorder of the photosynthetic complexes were responsible for disappearance of the chloroplast grana. CONCLUSIONS: Based on the presented results we postulate two phases of thallium toxicity on photosynthesis: the non-destructive phase at early stages of toxicant accumulation and the destructive phase that is restricted to the discolored leaf areas containing high toxicant content. There was no distinct border between the two phases of thallium toxicity in leaves and the degree of toxicity was proportional to the migration rate of the toxicant outside the vascular bundles. The three-fold (nearly linear) increase of Tl(I) concentration was observed in damaged tissue and the damage appears to be associated with the presence of the oxidized form of thallium - Tl(III).


Assuntos
Sinapis/efeitos dos fármacos , Sinapis/metabolismo , Tálio/toxicidade , Intoxicação por Metais Pesados , Metais Pesados/toxicidade , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Intoxicação , Sinapis/genética , Poluentes do Solo/toxicidade
10.
Mikrochim Acta ; 183: 177-183, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26766876

RESUMO

Alumina (Al2O3) with an average particle size of 63 µm was modified with the anionic surfactant sodium dodecyl sulfate (SDS) and then applied to (i) solid phase extraction and separation of both thallium(I) and thallium(III), and (ii) preconcentration of Tl(III) from waste water samples. Only Tl(III), in the form of its complex with diethylenetriaminepentaacetate (DTPA), was retained on the sorbent, from where it can be eluted with 40 % nitric acid. Thallium species were then quantified by ICP MS. The method was characterized by a LOD of 25 pg of Tl(I) and 160 pg of Tl(III) in 10 mL samples. A large excesses of Tl(I) over Tl(III) was tolerated, and relatively high levels of other metal ions, such as a 500-fold excess of Pb(II) and Cd(II), and a 2000-fold excess of Zn(II), respectively, do not interfere. The sorbent was easily prepared and possesses a high loading capacity, and these properties make it an attractive material for rapid and efficient extraction and speciation of Tl. Graphical abstract:Schematic of the SPE procedure for separation (with preconcentration) of Tl(III) from Tl(I) was developed and applied to direct speciation analysis of thallium in wastewater. Self-made columns packed with alumina coated with SDS were used. The method is resistant to interferences from Pb, Cd, Zn and tolerates a large excess of Tl(I) over Tl(III).

11.
Chemosphere ; 144: 1216-23, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26465967

RESUMO

The paper presents both "good" and "bad" results obtained during speciation analysis of thallium in plant tissues of a hyperaccumulator of this metal. The object was white mustard - Sinapis alba L. In this plant there were found traces of trivalent thallium. The crucial point of this study (especially in the case of so unstable thallium form as Tl(III)) was to prove that the presence of Tl(III) was not caused by the procedure of sample preparation itself, and that the whole analytical method provides reliable results. Choice of the method for conservation of the initial speciation, extraction with the highest efficiency and proving the correctness of the obtained data were the most difficult parts of the presented study. It was found that: both freezing and drying cause significant changes in the speciation of thallium; quantitative analysis could be performed only with fresh tissues of mustard plants; only short-term storage of an extract from fresh plant tissues is possible; the methodology is not the source of thallium (III); only the presence of DTPA can greatly limit the reduction of TI(III) to TI(I) (up to 1-3%); the UV irradiation results in disintegration of TI(III)DTPA in the presence of plant matrix (reduction up to 90%).


Assuntos
Monitoramento Ambiental/métodos , Sinapis/química , Poluentes do Solo/análise , Tálio/análise , Cromatografia Líquida de Alta Pressão/métodos , Oxirredução , Ácido Pentético/química , Folhas de Planta/química , Padrões de Referência , Poluentes do Solo/química , Espectrofotometria Atômica/métodos , Tálio/química
12.
Ann Agric Environ Med ; 21(2): 450-3, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24959808

RESUMO

INTRODUCTION: Infertility is defined as a state when a couple fails to conceive a pregnancy after one year of regular intercourse without the use of contraception. Alcohol consumption is one of the main stimulants which negatively affect the female and male reproductive system. OBJECTIVE: The objective of the study was analysis of the effect of alcohol consumption by the examined women on the quality of embryos obtained during in vitro fertilization programmes. MATERIAL AND METHODS: The study covered 54 women who received treatment due to infertility. The database and statistical analyses were performed using computer software STATISTICA 7.1 (StatSoft, Poland). RESULTS: The study showed that 42.59% from among 100% of the women in the study consumed alcohol. In the group of women who consumed alcohol, class A embryos constituted 4.35%, class B embryos - 86.96%, while embryos of class C - 8.69%. A statistically significant difference was observed between the classes of embryos and alcohol consumption by the women examined (p=0.001). In addition, a statistically significant relationship was found between the amount of alcohol consumed and the classes of embryos (p=0.005). A significantly larger number of class B embryos came from women who consumed more than 25 grams of ethyl alcohol daily (72.72%), compared to those who consumed alcohol sporadically (44.44%), or those who abstained entirely from alcohol (30.00%). CONCLUSIONS: Alcohol consumption causes the development of poorer quality embryos. Significantly more embryos of class B came from oocytes of women who consumed alcohol, compared to class A. An active campaign against alcohol consumption should be carried out among women at reproductive age to safeguard their fertility and future motherhood.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Adulto , Bebidas Alcoólicas/toxicidade , Embrião de Mamíferos/efeitos dos fármacos , Feminino , Fertilização in vitro/efeitos dos fármacos , Humanos , Polônia , Adulto Jovem
13.
Talanta ; 112: 73-9, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23708540

RESUMO

The main difficulty of speciation analysis of thallium lies in extremely low concentrations of Tl(III) in comparison to Tl(I), which is the dominating form of thallium in environmental samples. In this study, a sensitive method is presented for separation of trace amounts of Tl(III) from Tl(I) and preconcentration of Tl(III) using octadecyl silica gel modified with diethyldithiocarbamate (DDTC). Under optimal conditions, only Tl(III) is retained on the sorbent, and then eluted with 96% ethanol. After chemical decomposition of Tl(III)-DDTC complex, thallium is determined by inductively coupled plasma mass spectrometry. High performance liquid chromatography with ICP MS detection was used to control the correctness of the obtained results. Parameters affecting solid phase extraction (SPE) such as pH, type, concentration and volume of eluent, breakthrough volume, and the impact of sample salinity (chlorides) and other interfering ions (Cd(II), Zn(II), Pb(II), Cu(II), Sn(II)) were investigated. The limit of detection (LOD), evaluated for 2 mL of sample solution, was 0.10 ng for Tl(I) and 0.43 ng for Tl(III). The method was applied to the determination of Tl(I) and Tl(III) in the Baltic seawater samples enriched in both thallium species.


Assuntos
Espectrometria de Massas/métodos , Água do Mar/análise , Tálio/análise , Poluentes Químicos da Água/análise , Ditiocarb/química , Monitoramento Ambiental , Oceanos e Mares , Sílica Gel/química
14.
Talanta ; 93: 326-9, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22483918

RESUMO

Besides the dominant species in plants-Tl(I), noticeable amounts of Tl(III) (about 10% of total Tl content) were found in extracts of plants cultivated in the presence of tailing sediments, which are the main source of anthropogenic thallium already present in the environment. It is an important step of gaining knowledge about the detoxification mechanisms developed by Sinapis alba. This plant species is highly tolerant to Tl and it is able to cumulate high amounts of Tl and transport it into the above-ground organs. For more adequate estimation of accumulating abilities of S. alba, the elements' bioavailability was taken into consideration. The obtained bioconcentration factors of Cd (AF=0.6) and Zn (AF=1-2) were significantly lower than of Tl (AF=100-200). The biomass production was similar to the biomass of control cultivation. The results were based on ICP MS measurements of total elements' content and HPLC ICP MS for speciation analysis. The quality of obtained results was evaluated based on the intermethod comparison with voltammetry as a reference method. Comparison of data obtained using ICP MS and electrochemical methods (after a proper chemical treatment) was also used for indication of Tl(III) presence and for proving that Tl(I) was not transferred into Tl(III) during analytical procedures.


Assuntos
Sedimentos Geológicos/química , Minerais/química , Sinapis/crescimento & desenvolvimento , Sinapis/metabolismo , Solo/química , Tálio/química , Tálio/metabolismo , Biomassa , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Sinapis/efeitos dos fármacos , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Tálio/toxicidade
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