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1.
Heliyon ; 10(17): e37250, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39296217

RESUMO

Human health is being increasingly exposed to fluoride and nitrate ingestion globally due to anthropogenic alternations in groundwater resources. In the present research work, a hazard quotient (HQ), Monte Carlo simulation (MCS), and geographic information systems (GIS) have been used to estimate the non-carcinogenic health risk of nitrate and fluoride in vulnerable adults, teenagers, and children living in far-flung areas of Uttar Pradesh, Northern India. About 110 samples from some nearby populations were collected and analyzed for nitrates by ion chromatography and fluoride by a fluoride-selective electrode. The results indicated that the concentrations of fluoride and nitrate in the sampling areas ranged from 0.21 to 1.71 mg/L and 0.4-183.54 mg/L, respectively, with mean concentrations of about 1.20 mg/L and 51.52 mg/L for fluoride and nitrate, respectively. The results indicated that 27.27 % of the fluoride samples (27 out of 110) and 45.45 % of the nitrate samples (44 out of 110) were above the standard limits set by WHO. The calculated average HQ values fluoride and Nitrate for children, teenagers and adults were 1.88, 0.98, 0.90 and 3.02, 1.57, 1.45 respectively The 95th percentile HQ values for fluoride were 2.87 for children and 1.03 for adults, while those for nitrate were 4.10 for children and 1.98 for adults. Results of the health risk assessment show that there is a high potential for both non-carcinogenic and cancer risks from fluoride and nitrate through the consumption of groundwater. The Monte Carlo simulation showed the uncertainties and increased risks for children; therefore, one can infer that rural groundwater of the Mathura region, Uttar Pradesh, India, must be treated to make it potable for consumption.

2.
Nanoscale ; 16(28): 13445-13456, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38920340

RESUMO

The unpaired electron in the gold clusters (Aun, n = no. of Au atoms) with an odd number of total electrons is solely responsible for the magnetic properties in the small-sized Au nano-clusters. However, no such unpaired electron is available due to pairing in the even number of atom gold clusters and behaving as a diamagnetic entity similar to bulk gold. In this work, we unveiled the spin-density distribution of odd Aun clusters with n = 1 to 19 that reveals that a single unpaired electron gets distributed non-uniformly among all Au-atoms depending on the cluster size and morphology. The delocalization of the unpaired electron leads to the spin dilution approaching a value of ∼1/n spin moments on each atom for the higher clusters. Interestingly, small odd-numbered gold clusters possess spin-magnetic moments similar to the delocalized spin moments as of organic radicals. Can cooperative magnetic properties be obtained by coupling these individual magnetic gold nanoparticles? In this work, by applying state-of-the-art computational methodologies, we have demonstrated ferromagnetic or anti-ferromagnetic couplings between such magnetic nanoclusters upon designing suitable organic spacers. These findings will open up a new avenue of nanoscale magnetic materials combining organic spacers and odd-electron nano-clusters.

3.
Sci Rep ; 14(1): 5381, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443485

RESUMO

The qualitative and quantitative assessment of groundwater is one of the important aspects for determining the suitability of potable water. Therefore, the present study has been performed to evaluate the groundwater quality for Achhnera block in the city of Taj, Agra, India, where groundwater is an important water resource. The groundwater samples, 50 in number were collected and analyzed for major ions along with some important trace element. This study has further investigated for the applicability of groundwater quality index (GWQI), and the principal component analysis (PCA) to mark out the major geochemical solutes responsible for origin and release of geochemical solutes into the groundwater. The results confirm that, majority of the collected groundwater samples were alkaline in nature. The variation of concentration of anions in collected groundwater samples were varied in the sequence as, HCO3- > Cl- > SO42- > F- while in contrast the sequence of cations in the groundwater as Na > Ca > Mg > K. The Piper diagram demonstrated the major hydro chemical facies which were found in groundwater (sodium bicarbonate or calcium chloride type). The plot of Schoellar diagram reconfirmed that the major cations were Na+ and Ca2+ ions, while in contrast; major anions were bicarbonates and chloride. The results showed water quality index mostly ranged between 105 and 185, hence, the study area fell in the category of unsuitable for drinking purpose category. The PCA showed pH, Na+, Ca2+, HCO3- and fluoride with strong loading, which pointed out geogenic source of fluoride contamination. Therefore, it was inferred that the groundwater of the contaminated areas must be treated and made potable before consumption. The outcomes of the present study will be helpful for the regulatory boards and policymaker for defining the actual impact and remediation goal.

4.
Sci Rep ; 13(1): 18971, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37923921

RESUMO

This study quantifies the groundwater fluoride contamination and assesses associated health risks in fluoride-prone areas of the city of Taj Mahal, Agra, India. The United States Environmental Protection Agency (USEPA) risk model and Monte Carlo Simulations were employed for the assessment. Result revealed that, among various rural and urban areas Pachgain Kheda exhibited the highest average fluoride concentration (5.20 mg/L), while Bagda showed the lowest (0.33 mg/L). Similarly, K.K. Nagar recorded 4.38 mg/L, and Dayalbagh had 1.35 mg/L. Both urban and rural areas exceeded the WHO-recommended limit of 1.5 mg/L, signifying significant public health implications. Health risk assessment indicated a notably elevated probability of non-carcinogenic risk from oral groundwater fluoride exposure in the rural Baroli Ahir block. Risk simulations highlighted that children faced the highest health risks, followed by teenagers and adults. Further, Monte Carlo simulation addressed uncertainties, emphasizing escalated risks for for children and teenagers. The Hazard Quotient (HQ) values for the 5th and 95th percentile in rural areas ranged from was 0.28-5.58 for children, 0.15-2.58 for teenager, and 0.05-0.58 for adults. In urban areas, from the range was 0.53 to 5.26 for children, 0.27 to 2.41 for teenagers, and 0.1 to 0.53 for adults. Physiological and exposure variations rendered children and teenagers more susceptible. According to the mathematical model, calculations for the non-cancerous risk of drinking water (HQ-ing), the most significant parameters in all the targeted groups of rural areas were concentration (CW) and Ingestion rate (IR). These findings hold relevance for policymakers and regulatory boards in understanding the actual impact and setting pre-remediation goals.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Criança , Adulto , Adolescente , Humanos , Fluoretos/efeitos adversos , Fluoretos/análise , Método de Monte Carlo , Poluentes Químicos da Água/análise , Água Potável/análise , Índia , Medição de Risco , Monitoramento Ambiental
5.
Environ Sci Pollut Res Int ; 29(4): 5881-5890, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34431052

RESUMO

Prevalence of fluorosis is a worldwide public health problem especially in many states of India. It is necessary to find out the fluoride endemic areas to adopt remedial measures to the people on the risk of fluorosis. The target goals of this research were to assess (a) the exposure of fluoride concentration; (b) probabilistic risk assessment, sensitivity analysis, and uncertainty through intake of groundwater among population of Agra City (infants, children and adults) by Crystal Ball software; and (c) spatial distribution of HQ and fluoride concentration. A total of sixty samples from standing tube wells/hand pumps were gathered from selected and identified fluoride prevalent areas in Agra City. The concentration of fluoride scrutinized was obtained to be ranging from 1.32 to 4.60 mg/L with mean value of 2.36 in Agra City, and more than 91% of samples investigated surpassed the allowable level set for fluoride concentration in potable water 1.5 mg/L, although 9% of the samples were well within the drinking water guidelines (0.5-1.5 mg/L). The hazard quotient (HQ) was obtained to an enormous difference in the exposure dose in infants (1.66-3.91), children (1.87-4.4), and adults (0.92-2.16), correspondingly. The non-carcinogenic HQ values in the group of infants, children, and more than 90% of adults were higher than those of the safety level (i.e., HQ >1). Consequently, the non-carcinogenic risks (HQ level) of fluoride vary from the most to the least: children, infant, and adults, respectively. With 87.41% certainty, the results indicated that the HQ values are between 1 and 3.42. So, infant is the most vulnerable group to fluoride consumption in study area. Uncertainty analysis results indicated that the children group's HQ level was between 1 and 1.90 with 38.48% certainty. To avoid further worsening of the situation as far as health is concerned, remedial actions like alternate sources of water supply and appropriate treatment of water need to be adopted besides required medical attention to affected people.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Adulto , Criança , Água Potável/análise , Monitoramento Ambiental , Fluoretos/análise , Sistemas de Informação Geográfica , Humanos , Lactente , Método de Monte Carlo , Medição de Risco , Análise Espacial , Poluentes Químicos da Água/análise
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