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1.
Int J Mol Sci ; 24(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37762092

RESUMO

Microporous sodium titanosilicate, Na2TiSiO5, has been successfully prepared using the sol-gel method. The structural and morphological characterization of synthesized product has been made via thermal analyses (TG-DTG), X-ray diffraction (XRD), and electron microscopy (SEM and TEM). Adsorption properties of the synthesized Na2TiSiO5 nanopowder for Pb(II) removal of aqueous media was investigated in different experimental conditions such as the contact time, the initial metal concentration, the pH, and the temperature. The Pb(II) adsorption on Na2TiSiO5 was discussed according to the kinetics and thermodynamics models. The adsorption kinetics of Pb(II) have been better described by the PS-order kinetic model which has the highest fitting correlation coefficients (R2: 0.996-0.999) out of all the other models. The adsorption results have been successfully fitted with the Langmuir and Redlich-Paterson models (R2: 0.9936-0.9996). The calculated thermodynamic parameters indicate that the Pb(II) adsorption is an endothermic process, with increased entropy, having a spontaneous reaction. The results have revealed a maximum adsorption capacity of 155.71 mg/g at 298 K and a very high adsorption rate at the beginning, more than 85% of the total amount of Pb(II) being removed within the first 120 min, depending on the initial concentration.


Assuntos
Chumbo , Sódio , Termodinâmica , Entropia , Temperatura
2.
J Water Health ; 20(9): 1380-1392, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36170192

RESUMO

Fluoride has both beneficial and detrimental effects on human health. Concentrations of fluoride less than 1.0 mg/L in ingested water are beneficial for the rate of tooth decay, especially in children. The aims of the paper are as follows: (i) to monitor fluoride concentrations in drinking water samples (well water and tap water from the rural district of Valea Râmnicului, Romania); (ii) to study and select the optimal buffer solution and the optimal volume used in the analyses and (iii) to validate the potentiometric method for determining fluoride ions with a selective ion electrode. The values of fluoride ion concentrations in the groundwater samples and in tap water varied from 0.01 to 0.138 mg/L. The values for the hazard quotient for the studied samples varied from 0.01 to 0.13.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Criança , Água Potável/análise , Monitoramento Ambiental/métodos , Fluoretos , Flúor/análise , Água Subterrânea/análise , Humanos , Medição de Risco , Romênia , Poluentes Químicos da Água/análise
3.
J Dairy Res ; 83(2): 261-5, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27210498

RESUMO

This Research Communication reports analysis of 37 compounds comprising polycyclic aromatic hydrocarbons (PAHs), organochlorine and organophosphate pesticides (OCPS and OPPS) in milk powder (one brand each of commercial infant formulae, follow-on formulae and baby formulae purchased from a local supermarket in Romania). The selected analytes were investigated using gas chromatography-mass spectrometry (GC-MS), gas chromatography with electron capture detector (GC-ECD) and gas chromatography with thermionic sensitive detection (GC-TSD). The estimated limits of detection for most target analytes were in the µg/kg level (range 0·001-0·320 µg/kg). The purpose of the study was to determine the selected analytes, to assess the exposure of babies and infants and to produce data for comparison with tolerable limits according to the European Union Regulations. In most of the samples the organochlorine pesticides values were under the limit of detection. Exceptions were heptachlor epoxide and endosulfan sulphate, the last of which was found in all analysed samples at low concentrations. We also found detectable levels of ethoprophos, parathion-methyl, chlorpyrifos, prothiofos, guthion, disulfoton and fenchlorphos in most of the analysed samples. Benzo[a]pyrene, which is used as an indicator for the presence of PAHs, was not detected in selected samples. The low level of exposure to contaminants indicates that there are no health risks for the infants and babies that consume this brand of milk powder formulae.


Assuntos
Contaminação de Alimentos/análise , Alimentos em Conserva/análise , Leite/química , Praguicidas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Hidrocarbonetos Clorados/análise , Lactente , Fórmulas Infantis/química , Recém-Nascido , Concentração Máxima Permitida , Organofosfatos/análise , Romênia
4.
Biol Trace Elem Res ; 202(5): 2347-2356, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37542593

RESUMO

Mushrooms are a good source of protein and phenolic compounds which provides health benefits for humans. The purpose of this study was to compare the content of eight metals, protein, and total phenolics (TPC) of 5 different species (Agaricus bisporus-white and brown mushrooms, Agaricus cupreobrunneus, Auricularia cornea, Hypsizgus tesselatus, and Pleurotus eryngii species-complex) of edible mushrooms available on the Romanian market. Agaricus bisporus and Agaricus cupreobrunneus were purchased and cultivated in Romania and the other species were cultivated in other countries (Turkey and China). The metal content determined by graphite atomic absorption spectrometry (GTAAS) varied in the order Cu > Pb > Ni > Fe > Cr > Mn > Co > Cd. Almost all the samples contained a greater quantity of metals in the stalk than in the cap. In addition, the levels of toxic metals were low. The protein content of analyzed samples ranged from 0.0926 to 0.2743%, the highest value being observed in Pleurotus eryngii species-complex mushroom. TPC of extracts increased over time but there was a variability in the concentration for each mushroom species (0.25-12.25 mg GAE/g). The investigated mushroom species possess no health risk and may be potential nutritional supplements for human diets due to their phenolic compounds, protein, and mineral content.


Assuntos
Agaricales , Agaricus , Pleurotus , Humanos , Agaricales/química , Agaricus/química , Metais/análise , Medição de Risco
5.
Biol Trace Elem Res ; 201(3): 1547-1556, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35488023

RESUMO

In this study, the content of lead (Pb), cadmium (Cd), chromium (Cr) and manganese (Mn) was evaluated in soils and tomatoes (Lycopersicon esculentum) collected from rural areas of Dobrogea province, South-East of Romania. The risk to human health due to the heavy metal exposure via tomato consumption was also assessed.The results suggest that based on the contamination factor, the soils are moderately contaminated with Cd and Mn (Cf values of 1.266. and 1.40) and poorly contaminated with Pb and Cr. The bioconcentration factor (BAF) was below 1 and indicated that the studied species of Lycopersicon esculentum did not accumulate the monitored elements. Person's correlation analysis showed that there were significant relations between soil pH and BCF values of Cd, Pb, Cr and Mn in analysed tomatoes. The estimated daily intake of each metal was below the oral reference dose. The hazard quotient (HQ) and hazard index (HI) were below the acceptable level (< 1), and the cancer risk (CR) for Pb, Cd and Cr was found within acceptable levels (1.0 × 10-6-1.0 × 10-4). Based on health guidance values, it may be concluded that the analysed tomatoes do not present health risks to consumers in terms of content and accumulation of heavy metals. It is important to monitor the other toxic metals as well, in order to evaluate the heavy metal accumulation variation and the toxicity value of each metal in agricultural soils from both rural and industrial areas.


Assuntos
Metais Pesados , Poluentes do Solo , Solanum lycopersicum , Humanos , Cádmio/análise , Solo/química , Chumbo/análise , Monitoramento Ambiental , Medição de Risco , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Metais Pesados/análise , Cromo/análise , Manganês/análise , China
6.
Sci Total Environ ; 759: 143543, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33199012

RESUMO

The complex composition of grapes as well as the quite large variations of each component affect the processing thereof differently and at the same time influence the yield in must, its quality and the wine product; they also influence production losses, along with the quality and quantity of by-products. Vinification wastes cause ecological problems because the neutralization and use of fermentative wastes mixed with different compounds present a danger to the environment and to the health of the population. The ecological measures of protection of the environmental factors are very important, especially the economic efficiency obtained through the recovery of the by-products. This paper focuses on the possibilities of using the by-products obtained from the wine making process, based on the fact that this drink is the most widely known in the world, with the highest percentage in terms of beverage production and implicitly with the largest quantity of by-products obtained. The valorization of these by-products leads to obtaining very valuable products both from a nutritional and industrial point of view. Experimentally, the aim was to determine the physical and chemical characteristics of different types of grape pomace and must sampled from a winery in Romania. Thus, the determination of total acidity, conductivity, pH, total content of phenolic compounds, total nitrogen and total content of pectic substances was aimed. The experimental values obtained have shown that grape pomace is a valuable by-product of the wine industry and its valorization demonstrates an important economic efficiency.

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