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1.
Environ Geochem Health ; 46(6): 208, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806960

RESUMO

Concentrations of potentially toxic elements (PTEs) like arsenic, uranium, iron, and nitrate in the groundwater of the Majha Belt (including Tarn Taran, Amritsar, Gurdaspur, and Pathankot districts) in Punjab, India were measured to evaluate the health risks associated with its consumption and daily use. The average concentrations of these elements in some locations exceeded the WHO-recommended values. Arsenic and iron toxicity levels were found to be higher in the Amritsar district, while uranium toxicity was more prevalent in Tarn Taran. The Trace Element Evaluation Index suggests that Amritsar is one of the districts most affected by toxic elements. According to the US Environmental Protection Agency's (USEPA) guidelines, the HQ values of U, Fe, and nitrate were less than one, indicating that there is no non-carcinogenic health risk for adults and children. However, the hazard quotient (HQ) value for arsenic was greater than one, indicating a higher possibility of health risk due to arsenic in the study area. The total hazard index values of 44.10% of samples were greater than four for arsenic, indicating that people in the Majha Belt are at a very high health risk due to the usage of water for drinking and domestic purposes. The cancer risk assessment values for arsenic in children (5.69E + 0) and adults (4.07E + 0) were higher than the accepted limit of USEPA (10-4 to 10-6) in the Majha Belt. The average radiological cancer risk values of U for children and adults were 8.68E-07 and 9.45E-06, respectively, which are well below the permissible limit of 1.67 × 10-4 suggested by the Atomic Energy Regulatory Board of DAE, India. The results of this study confirm that the residents of the Majha Belt who use contaminated groundwater are at a serious risk of exposure to arsenic in the Amritsar district and uranium in Tarn Taran district.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Índia , Água Subterrânea/química , Medição de Risco , Arsênio/análise , Poluentes Químicos da Água/análise , Humanos , Urânio/análise , Nitratos/análise , Monitoramento Ambiental , Ferro/análise , Criança , Adulto
2.
Environ Pollut ; 351: 124032, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670425

RESUMO

Benthic fluxes refer to the exchange rates of nutrients and other compounds between the water column and the sediment bed in aquatic ecosystems. Their quantification contributes to our understanding of aquatic ecosystem functioning. Near-bed hydrodynamics plays an important role at the sediment-water interface, especially in shallow lakes, but it is poorly considered by traditional measuring techniques of flux quantification, such as sediment incubations. Thus, alternative sampling techniques are needed to characterize key benthic fluxes under in-situ hydrodynamic conditions. This study aimed to evaluate the performance of two promising methods: relaxed eddy accumulation (REA) and mass transfer coefficient (MTC). We applied them in a hyper-eutrophic shallow lake to measure the fluxes of ammonium, phosphate, iron, and manganese ions. For the first time, REA revealed hourly nutrient flux variations, indicating a strong lake biogeochemical dynamics at short time-scales. Daily average fluxes are of similar orders of magnitude for REA and MTC for ammonium (24 and 42 mmol m2 d-1), manganese (1.0 and 0.8), and iron (0.8 and 0.7) ions. They are one order of magnitude higher than fluxes estimated from sediment incubations, due to the difficulty in reproducing in-situ oxygen and hydrodynamic conditions in the laboratory. Although the accuracy of both techniques needs to be improved, the results revealed their potential: REA follows the short-term biogeochemical dynamics of sediments, while MTC could be widely used for lake monitoring because of its simpler implementation.


Assuntos
Compostos de Amônio , Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Poluentes Químicos da Água , Lagos/química , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Compostos de Amônio/análise , Ecossistema , Hidrodinâmica , Ferro/análise , Manganês/análise , Fosfatos/análise , Eutrofização
3.
J Environ Manage ; 356: 120559, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38471324

RESUMO

In November 2015, a catastrophic rupture of the Fundão dam in Mariana (Brazil), resulted in extensive socio-economic and environmental repercussions that persist to this day. In response, several reforestation programs were initiated to remediate the impacted regions. However, accurately assessing soil health in these areas is a complex endeavor. This study employs machine learning techniques to predict soil quality indicators that effectively differentiate between the stages of recovery in these areas. For this, a comprehensive set of soil parameters, encompassing 3 biological, 16 chemical, and 3 physical parameters, were evaluated for samples exposed to mining tailings and those unaffected, totaling 81 and 6 samples, respectively, which were evaluated over 2 years. The most robust model was the decision tree with a restriction of fewer levels to simplify the tree structure. In this model, Cation Exchange Capacity (CEC), Microbial Biomass Carbon (MBC), Base Saturation (BS), and Effective Cation Exchange Capacity (eCEC) emerged as the most pivotal factors influencing model fitting. This model achieved an accuracy score of 92% during training and 93% during testing for determining stages of recovery. The model developed in this study has the potential to revolutionize the monitoring efforts conducted by regulatory agencies in these regions. By reducing the number of parameters that necessitate evaluation, this enhanced efficiency promises to expedite recovery monitoring, simultaneously enhancing cost-effectiveness while upholding the analytical rigor of assessments.


Assuntos
Ecossistema , Compostos de Ferro , Solo/química , Monitoramento Ambiental , Mineração , Brasil , Ferro/análise , Cátions , Rios/química
4.
Environ Sci Pollut Res Int ; 30(59): 124010-124027, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37996578

RESUMO

This paper develops a process-level carbon emission calculation model for iron and steel enterprises through the carbon emission mechanism of the whole production process. The relationship between material, energy and carbon flows is considered and combined. The carbon emissions of enterprises are divided into industrial emissions and combustion emissions, and the indirect emissions of purchased intermediate products and electricity purchased from the grid are also considered. Carbon emission targets and corresponding emission reduction strategies are formulated at the enterprise and process levels. For example, consider an iron and steel enterprise. The different types of carbon emissions are accounted for, with their reduction potential analysed based on the carbon material flow analysis method. The results show that the carbon emission of this enterprise is 1930.87 kgCO2/t (CS), and the combustion emission caused by energy flow is the main contributor to the enterprise's carbon emission, accounting for 57.02% of the total emission. The carbon emission during iron-making accounts for 69.06% of the entire process and is critical in any carbon emission reduction of the enterprise. Among them, process emissions from the blast furnace process account for 81.79% of industrial emissions of the whole process, which is 356.51 kgCO2/t (CS), and is the main challenge of low carbon transformation in this extensive process. This study highlights that increasing the integrated steel-making scrap ratio and electric furnace steel production can break through the existing emission reduction limits. A 65.02% carbon emission reduction can be achieved, and using green electricity can reduce emissions by 24.15%. Reasonably determining the amount of purchased coke and paying attention to the high-value recycling of byproduct gas resources in the plant are essential to achieve low-carbon economic development of steel.


Assuntos
Dióxido de Carbono , Aço , Dióxido de Carbono/análise , Aço/análise , Carbono/análise , Ferro/análise , Reciclagem , China
5.
Nutrients ; 15(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37375704

RESUMO

The anthropogenic environment and diet introduce many metals into the human body, both essential and toxic. Absorption leads to systemic exposure and accumulation in body fluids and tissues. Both excess and deficiency of trace elements are health hazards. The primary aim of the present study was to evaluate the concentration of 51 elements in liver samples and 11 selected brain regions obtained at post-mortem examination from a population of adults living in south-eastern Poland (n = 15). A total of 180 analyses were performed by inductively coupled plasma mass spectrometry in two independent replicates. The collected data show very high individual variability in the content of the investigated elements. Macroelements such as sodium, magnesium, phosphorus, potassium, calcium, iron, and zinc occurred in the highest concentrations and with the greatest statistically significant variations. Although the elemental content of the brain and liver differed significantly, the strongest positive correlation between liver and polus frontalis was observed for the essential element selenium (0.9338) and the strongest negative one for manganese (-0.4316) and lanthanum (-0.5110). The brain areas studied have different requirements for phosphorus, manganese, iron, and molybdenum. In addition, males had a significantly (p < 0.05) higher brain content of lanthanides and actinides than females. The results of this study show that the inhabitants of south-eastern Poland are exposed to a fairly uniform accumulation of aluminum and vanadium in the brain, which have the highest affinity to the thalamus dorsalis. This result proves that there is environmental exposure to these elements.


Assuntos
Selênio , Oligoelementos , Masculino , Adulto , Feminino , Humanos , Manganês/análise , Oligoelementos/análise , Selênio/análise , Ferro/análise , Fósforo , Encéfalo , Fígado/química
6.
Environ Monit Assess ; 195(5): 608, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37095291

RESUMO

The current study aimed to examine how some gastropods absorbed trace metals (Chicoreus ramosus and Hemifusus pugilinus). The existence of 17 elements, including aluminium, arsenic, boron, calcium, cadmium, cobalt, chromium, copper, iron, potassium, lithium, manganese, sodium, nickel, phosphorus, lead, and zinc (Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mn, Na, Ni, P, Pb, and Zn), was confirmed by inductively coupled plasma-mass spectroscopy (ICP-MS) analysis of trace metals. According to the ICP-MS results, C. ramosus (Al: 1.97 ± 0.2 µg/g, Fe: 1.93 ± 0.2 µg/g, and As: 1.52 ± 0.4 µg/g) and H. pugilinus (Al: 1.85 ± 0.7 µg/g, Fe: 1.68 ± 0.6 µg/g, and As: 1.37 ± 0.6 µg/g) both had significant amounts of aluminium, iron, and arsenic, respectively. Zinc concentrations of 0.58 to 0.7 µg/g (C. ramosus) and 0.67 to 0.2 µg/g were recorded (H. pugilinus). The elemental composition of the surface of the sample was confirmed by scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX) micrographs, which also showed the degree of trace metal absorption in the chosen gastropod species.


Assuntos
Arsênio , Gastrópodes , Oligoelementos , Animais , Arsênio/análise , Alumínio , Bioacumulação , Monitoramento Ambiental/métodos , Oligoelementos/análise , Zinco/análise , Ferro/análise
7.
Environ Monit Assess ; 195(2): 299, 2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36640219

RESUMO

Use of medicinal herbs is now gaining popularity especially among the low-income people because it is cheap, readily available and its "seeming" lack of side effects. However, environmental pollution is a potential threat to its continued use. This study examines the effect of air pollution on the soil and consequently on the medicinal herbs grown on such soils. Soil and four medicinal herbs, Chromolaena odorata, Vernonia amygdalina, Carica papaya and Ocimum gratissimum, commonly used in the south western part of Nigeria either as purely medicinal herbs, soup vegetables or both were carefully harvested from Fasina, a polluted area, and Moro, a relatively unpolluted area, all in Ile-Ife, Nigeria. Samples were prepared following standard practice and analysed for nickel, chromium, cadmium and lead using atomic absorption spectroscopy (AAS). The results showed that elemental concentrations at the two locations were within the permissible limit for both soil and herbs, the statistical test also established no significant difference between the two locations. However, toxic metals concentrations (chromium, cadmium and lead) were found higher at the polluted site while that of the essential metal, nickel, was higher at the unpolluted site. Of the four metals, cadmium has the highest transfer ratio (0.39 and 0.34) while lead has the least (0.21 and 0.25) for Moro and Fasina sites respectively. Similarly, Chromolaena odorata has the highest transfer ratio (0.34) while Carica papaya has the least (0.28). In conclusion, gradual build-up of the toxic metals at the polluted site is evident and may eventually contaminate the herbs.


Assuntos
Metais Pesados , Plantas Medicinais , Poluentes do Solo , Humanos , Metais Pesados/análise , Ferro/análise , Níquel/análise , Cádmio/análise , Plantas Medicinais/química , Nigéria , Solo/química , Monitoramento Ambiental , Poluentes do Solo/análise , Poluição Ambiental/análise , Cromo/análise
8.
Chemosphere ; 312(Pt 1): 137176, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36400198

RESUMO

This study aims to conduct statistical optimization of nZVI synthesis parameters towards the removal efficiency of phosphorus (P) and nitrate (NO3-), considering for the first time the cost-effectiveness index. The detailed statistical analysis was implemented to evaluate the main effects and interactions of eight synthesis parameters, including reductant concentration (RC), reductant delivery rate (RDR), reductant liquid volume (RLV), pH, aging time (AGT), mixing speed (MS), temperature (T), and precursor concentration (PC). Results revealed that the experimental optimization of the synthesis factors improved the removal efficiency of NO3- and P by 27 and 9%, respectively, with respect to that before the optimization. ANOVA statistical results indicated the significance of RP (%) and [Formula: see text] (%) models with F-values of 4.480 × 108 and 23,755.08, respectively. Moreover, the p-values of all the eight main linear effects were less than 0.05 in both two models of RP (%) and [Formula: see text] (%). However, most of the interaction parameters were not statistically significant (higher than 0.05) in the case of [Formula: see text] (%), which is unlike RP (%) where all interaction parameters were statistically significant (less than 0.05). The normal probability plots of factors effects provided significant evidence of the significance of the investigated parameters RC had the highest positive statistically significant effect on RP (%) followed by RLV, RDR, MS and T. In case of [Formula: see text] (%), RLV had the highest positive significant effect, followed by AGT > RDR > pH > T > MS. The cost-effective optimal constraints in this study resulted in the best economically optimized values of the nZVI synthesis parameters in terms of higher reactivity and reduced synthesis cost.


Assuntos
Poluentes Químicos da Água , Análise Custo-Benefício , Poluentes Químicos da Água/análise , Ferro/análise , Substâncias Redutoras/análise , Nitratos/análise , Água
9.
Curr Med Imaging ; 19(7): 749-755, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36017836

RESUMO

INTRODUCTION: Since the most prominent effect of iron is increasing R2* and R2 relaxation rates, the iron-overload liver shows little signal with conventional T1ρ sequences like RARE. Whereas UTE MR imaging sequences can detect the signal from short T2/T2* relaxation components in tissues. This study aims to evaluate the difference in R1ρ profiles and compare the correlations between RARE-based and UTE-based sequences with LIC in assessing rat liver iron overload. METHODS: Iron dextran (Sigma, 100 mg Fe/ml) was injected into thirty-five rats (25-100 mg/kg body weight), while the rats in the control group were injected with saline (n=5). The liver specimen was taken after one week. A portion of the largest hepatic lobe was extracted to quantify the LIC by inductively coupled plasma, and the remaining liver tissue was stored in 4% buffered paraformaldehyde for 24 h before MRI. Spin-lock preparation with RARE readout and 2D UTE readout pulses were developed to quantify R1ρ on a Bruker 11.7T MR system. RESULTS: The mean R1ρ value of the rat liver with UTE-based R1ρ sequence was significantly higher compared to the RARE-based R1ρ sequence (p<0.001). Spearman's correlation analysis (two-tailed) indicated that the R1ρ values were significantly correlated with LIC for both UTE-R1ρ and RARER1ρ sequences (r = 0.727, P < 0.001, and r = 0.712, P < 0.001, respectively). CONCLUSION: The current study adds to evidence that there is a correlation between iron concentration and R1ρ. Moreover, the UTE-based R1ρ sequence is more sensitive to the liver iron than the RAREbased R1ρ sequence. R1ρ might serve as a complementary imaging biomarker for liver iron overload quantification.


Assuntos
Sobrecarga de Ferro , Humanos , Ratos , Animais , Sobrecarga de Ferro/diagnóstico por imagem , Ferro/análise , Imageamento por Ressonância Magnética/métodos , Fígado/diagnóstico por imagem , Complexo Ferro-Dextran
10.
Environ Sci Pollut Res Int ; 30(9): 23295-23311, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36322352

RESUMO

The existence of potentially toxic elements (PTEs) in water bodies has posed a menace to human health. Thus, water resources should be protected from PTEs, and their effect on the exposed population should be investigated. In the present investigation, the concentrations of PTEs such as lead (Pb), mercury (Hg), manganese (Mn), and iron(Fe) in the drinking water of Shiraz, Iran, were determined for the first time. In addition, hazard quotient, hazard index, cancer risk, and sensitivity analysis were applied to estimate the noncarcinogenic and carcinogenic impacts of Pb, Hg, Mn, and Fe on exposed children and adults through ingestion. The mean concentrations (µg/L) of Pb, Hg, Mn, and Fe were 0.36, 0.32, 2.28, and 8.72, respectively, in winter and 0.50, 0.20, 0.55, and 10.36, respectively, in summer. The results displayed that Fe concentration was more than the other PTEs. PTE concentrations were lower than the standard values of the Environment Protection Agency and World Health Organization. Values of the degree of contamination and heavy metal pollution index for lead, mercury, manganese, and iron were significantly low (< 1) and excellent (< 50), respectively. Based on the Spearman rank correlation analysis, positive and negative relationships were observed in the present study. The observations of the health risk assessment demonstrated that mercury, lead, iron, and manganese had an acceptable level of noncarcinogenic harmful health risk in exposed children and adults (hazard quotients < 1 and hazard index < 1). The carcinogenic risk of lead was low (< E - 06), which can be neglected. Monte Carlo simulation showed that water intake rate and mercury concentration were the most critical parameters in the hazard index for children and adults. Lead concentration was also the most crucial factor in the cancer risk analysis. The results of the present study proved that the drinking water of Shiraz is safe and healthy and can be confidently consumed by people.


Assuntos
Água Potável , Mercúrio , Metais Pesados , Neoplasias , Poluentes do Solo , Adulto , Criança , Humanos , Chumbo/análise , Água Potável/análise , Manganês/análise , Irã (Geográfico) , Monitoramento Ambiental/métodos , Metais Pesados/análise , Mercúrio/análise , Ferro/análise , Medição de Risco/métodos , Carcinógenos/análise , Carcinogênese , Poluentes do Solo/análise
11.
Environ Monit Assess ; 194(Suppl 2): 774, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36255503

RESUMO

Analysis of temporal patterns of high-dimensional time-series water quality data is essential for pollution management worldwide. This study has applied dynamic factor analysis (DFA) and cluster analysis (CA) to analyze time-series water quality data monitored at the five stations installed along the La Buong river in Southern Vietnam. Application of the DFA identified two types of temporal patterns, one of the run-off driven parameters (total suspended solid (TSS), turbidity, and iron) and the other of diffuse source pollution. The association of the variables like BOD5 and COD at most stations to the run-off-driven parameters revealed their sharing of drivers. On the contrary, separating variables like phosphate (PO43) at the three upstream stations from the run-off patterns suggested their local point-source origin. The DFA-derived factors were later used in the time-point CA to explore the seasonality of water quality parameters and their pollution intensities compared to regulatory levels. The result suggested intensification in wet season of Fe, TSS, BOD5, and COD concentrations at most sites, which are unobservable in run-off detached parameters like reactive nitrogen, phosphate (PO43-), and E. coli. These findings generated robust insights to support water quality management for river habitat conservation.


Assuntos
Rios , Poluentes Químicos da Água , Humanos , Monitoramento Ambiental/métodos , Escherichia coli , Vietnã , Qualidade da Água , Análise Multivariada , Ecossistema , Nitrogênio/análise , Fosfatos/análise , Ferro/análise , Povo Asiático , Poluentes Químicos da Água/análise , Poluição da Água/análise
12.
J Environ Manage ; 323: 116214, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36115238

RESUMO

Due to anthropogenic actions, the presence of pollutants in water bodies, such as toxic metals, are increasingly negatively affecting water quality, biodiversity and sustainable goals worldwide. Therefore, decentralization of water pollution monitoring with low-cost devices, such as using smartphones, suggests an innovative green technology for in situ and real-time control. In this study, a Handheld Smartphone Spectrophotometry System (HSSS) was developed to estimate copper and iron concentration water samples. The system mainly comprises a portable commercial spectrometer (GoSpectro) that can measure the spectrum of light in the visible region. The HSSS LOD and LOQ for copper were equal to 0.589 and 1.784 mg/L, respectively, and 0.479 and 1.450 mg/L, respectively for iron. In addition, the results of copper and iron concentrations in samples with unknown concentrations using HSSS were close to the Benchtop Spectrophometer (BS). Finally, HSSS performance showed to be a new green technology for water quality management with potential applications for monitoring water resources and also providing further possibilities to measure other pollutants by the same technique, in addition to metals.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes Químicos da Água , Cobre/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Ferro/análise , Metais Pesados/análise , Smartphone , Análise Espectral , Poluentes Químicos da Água/análise , Poluição da Água/análise
13.
Metallomics ; 14(9)2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36087072

RESUMO

The children today are in the midst of the epidemic of neurodevelopmental disorders. In this metallomics study for the scalp hair samples of total 2550 children with autistic disorders (2108 males and 442 females aged 0-15 years), it was demonstrated that near one-half of the infantile individuals aged 0-3 years are suffering from zinc deficiency and toxic metal burdens. Zinc level correlated closely to the index of zinc/iron ratio more than zinc/copper ratio. Furthermore, there were significant relationships between zinc deficiency and toxic metal burdens such as lead and aluminum, which were inversely associated with not only zinc level but also zinc/iron ratio with higher regression coefficients of r = -0.486 and -0.551 (P < 0.00001), respectively. High-significant inverse association was detected between zinc and molybdenum concentration (r = -0.509) and also between zinc/iron ratio and molybdenum (r = -0.548). These findings suggest that infantile zinc deficiency relates to the high burdens of not only toxic but also some essential metals such as molybdenum, iron, and manganese and that these various mineral imbalances play principal roles in the etiology of neurodevelopmental disorders. We expect that the early assessment and intervention of the mineral imbalances (or dis-homeostasis) in individual child open an avenue for evidence-based individualized treatment of neurodevelopmental disorders and also of the comorbid immune disorders, in near future.


Assuntos
Cobre , Transtornos do Neurodesenvolvimento , Alumínio , Criança , Cobre/análise , Feminino , Humanos , Ferro/análise , Masculino , Manganês/análise , Minerais , Molibdênio , Transtornos do Neurodesenvolvimento/diagnóstico , Zinco/análise
14.
Environ Monit Assess ; 194(9): 635, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35922718

RESUMO

Sediments from banks of the Sutlej River and roadside soils from vicinity of Ropar wetland (collected during pre- and post-monsoon seasons, 2013) were analysed to determine the spatiotemporal distribution of potentially toxic elements (PTEs, viz. arsenic, cadmium, cobalt, chromium, copper, iron, manganese, lead and zinc), which when present in high concentrations may pose health hazards and ecological risk. Contamination factor, degree of contamination, modified degree of contamination, metal pollution index, pollution load index, enrichment factor, geoaccumulation index and ecological risk index were also determined for these PTEs in the study area. Sediment and soil samples were found to be alkaline and non-saline (pH > 7.0; EC < 4500 µS cm-1) with sodium and potassium as major ions. Iron (mg kg-1) was found to be most abundant in sediments (1477.59-6512.45) and soils (922.64-12,455.00). Cadmium content in sediments exceeded the threshold value (0.99 mg kg-1) at 2 (pre-monsoon) and 3 (post-monsoon) sampling sites. In both seasons, cadmium (0.10-2.05) and cobalt (11.40-17.52) contents (mg kg-1) exceeded the threshold limits (0.06 and 8.00 respectively) in all roadside soils. Significant spatiotemporal variation (p ≤ 0.05) was observed for pH; EC; and calcium, magnesium, copper, iron and zinc contents. Low to moderate potential ecological risk was observed for both roadside soils (31.80-213.82) and sediments (41.47-236.73). Contamination factor, enrichment factor and geoaccumulation index for cadmium were highest in roadside soils (6.84, 46.91 and 2.19, respectively) and sediments (7.64, 167.46 and 2.35, respectively) due to settlement of coal fly ash released from the industrial setups, on sediments/soils of the study area.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/análise , Cobalto/análise , Cobre/análise , Monitoramento Ambiental , Sedimentos Geológicos/química , Ferro/análise , Metais Pesados/análise , Medição de Risco , Solo/química , Poluentes do Solo/análise , Áreas Alagadas , Zinco/análise
15.
Environ Sci Pollut Res Int ; 29(54): 82014-82029, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35748987

RESUMO

This study aimed to quantify the exposure of foundry workers to crystalline silica and associated cancer and non-cancer health risks using a probabilistic approach. Breathing zone air samples were collected according to the NIOSH 7602 method and analyzed using Fourier transform infrared spectroscopy. The health risks posed by crystalline silica were then assessed using the EPA-developed inhalation risk assessment model and Monte Carlo simulation. The sensitivity analysis was also conducted to determine the contribution of input parameters to the health risks. The mean concentration of crystalline silica in six foundry stations ranged from 0.029 to 0.064 mg m-3, exceeding the occupational exposure limits. The average values of cancer risks were greater than the USEPA level, i.e., 1E - 6 in all workstations of the foundry. Workers in sand preparation and molding stations suffered the greatest cancer risks, with the mean value of 2.35E - 5 and 2.10E - 5, respectively. Non-cancer hazard quotient exceeded 1 in all foundry stations ranging from 1.56 (in melting and pouring) to 3.37 (in sand preparation). The 95% upper-bound values of the health risks decreased by 77.52% and 56.77%, assuming the use of engineering controls and wearing respirators by workers, respectively. Sensitivity analyses indicate that concentration was the most sensitive factor contributing to the carcinogenic (46.13%) and non-carcinogenic (67.08%) risks. These findings can aid managers in gaining a better understanding of the silica risks faced by foundry workers and the role of engineering controls and respirators in protecting workers' health.


Assuntos
Exposição Ocupacional , Dióxido de Silício , Humanos , Dióxido de Silício/análise , Ferro/análise , Areia , Irã (Geográfico) , Exposição Ocupacional/análise , Medição de Risco , Exposição por Inalação/análise
16.
Eur J Radiol ; 154: 110412, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35724580

RESUMO

PURPOSE: To evaluate the diagnostic accuracy of the dual gradient-echo (GRE) in- and out-of-phase sequences as a quantitative tool for hepatic iron overload in comparison with MRI R2* relaxometry in paediatric patients with beta-thalassemia. METHOD: Sixty-three patients with beta-thalassemia major (transfusion-dependent) or beta-thalassemia intermedia (transfusion- and non-transfusion-dependent) were referred from the paediatric department (haematology unit) to the radiology department at a university hospital. The paediatrician conducted a clinical examination for the studied group, assessed their laboratory data, conducted R2* relaxometry and dual gradient echo sequences to calculate R2* and relative signal intensity index at the axial mid-section of the liver, and studied their correlation. A 1.5 Tesla MR scanner was used (Achieva; Philips Medical Systems, the Netherlands). Data were fed to the computer and analysed using the IBM SPSS software package version 20.0 (Armonk, NY: IBM Corp). The Kolmogorov-Smirnov test was used to verify the normality of distribution. The significance of the results was determined at the 5% level. The Chi-square, Fisher's exact correction, Pearson coefficient, and Bland-Altman tests were used. RESULTS: Dual gradient-echo in- and out-of-phase sequences using visual assessment accurately assessed 93.65% of our patient group with hepatic iron overload. A significant correlation was found between the relative signal intensity index and hepatic MRI R2* relaxometry (p < 0.001, r = 0.861). CONCLUSIONS: Dual gradient-echo in and out-of-phase sequences are good imaging tools for hepatic iron detection and quantification. These sequences showed good correlation with R2* relaxometry (r = 0.861, p < 0.001).


Assuntos
Sobrecarga de Ferro , Talassemia beta , Criança , Humanos , Ferro/análise , Sobrecarga de Ferro/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Talassemia beta/complicações , Talassemia beta/diagnóstico por imagem
17.
J Water Health ; 20(6): 888-902, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35768965

RESUMO

This study investigated groundwater pollution and potential human health risks from arsenic, iron, and manganese in the rural area of Jashore, Bangladesh. Study results show that the mean value of groundwater pH is 7.25 ± 0.31, with a mean conductivity of 633.94 ± 327.41 µs/cm, while about 73, 97, and 91% of groundwater samples exceeded the Bangladesh drinking water standard limits for As, Fe, and Mn, respectively. Groundwater pollution evaluation indices, including the heavy metal pollution index, the heavy metal evaluation index, the degree of contamination, and the Nemerow pollution index, show that approximately 97, 82, 100, and 100% of samples are in the high degree of pollution category, respectively. Spatial distribution exhibited that the study area is highly exposed to As (73%), Fe (82%), and Mn (46%). In the case of non-carcinogenic health risk via oral exposure, about 94% of samples suggest a high category of risk for infants, and 97% of samples are found to be at high risk for children and adults. The carcinogenic risk of arsenic via an oral exposure pathway suggests that approximately 97% of the samples are found to be at high risk for infants, and all of the samples are at high risk for both adults and children.


Assuntos
Arsênio , Água Subterrânea , Metais Pesados , Poluentes Químicos da Água , Adulto , Arsênio/análise , Arsênio/toxicidade , Bangladesh , Criança , Monitoramento Ambiental , Humanos , Ferro/análise , Manganês/análise , Manganês/toxicidade , Medição de Risco , Poluentes Químicos da Água/análise
18.
Biodemography Soc Biol ; 67(2): 133-149, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35593158

RESUMO

This study is conducted to decompose inequality in four important micronutrient intakes, i.e. calcium, iodine, iron, and zinc due to socioeconomic factors during 2006-2016. For this purpose, data were taken from national-level surveys, i.e. HIES-2006 and HIICS-2016. We applied a recently proposed decomposition method based on copula function to decompose between year changes in the consumption of micronutrients into structure and composition effect. The results show that average calcium and iron intakes increased by 518.54 (mg) and 0.962 (mg), respectively, while average iodine and zinc intakes decreased by 2.009 (mg) and 3.411 (mg), respectively, during the decade. Estimates of structure effect show that calcium, iodine, and iron consumption increased on average, i.e. 525.316 (mg), 14.615 (mg), and 2.15 (mg), respectively, while zinc intake decreased by 2.735 (mg). The composition effect is negative for all the four micronutrients, implying that consumption of calcium, iodine, iron, and zinc decreased as 6.7766 (mg), 16.624 (mg), 1.189 (mg), and 0.677 (mg), respectively. The main factors of this change are household income, urbanization, provinces, and household size. The policymakers need to know the importance of socioeconomic factors to improve hidden hunger in terms of micronutrient intakes.


Assuntos
Iodo , Micronutrientes , Cálcio , Humanos , Ferro/análise , Paquistão , Fatores Socioeconômicos , Zinco/análise
19.
Sci Rep ; 12(1): 4460, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292709

RESUMO

Diet based on cereal, vegetables, oleaginous and dried fish are providing essential metallic elements. It can be also a source of exposure to toxic metallic elements. The aims of this study were to evaluate the contents on nine metallic trace elements (Fe, Zn, Mn, Co, Cd, Pb, Cu, Ni, Cr) in some major raw foodstuffs including rice, maize, peanut, tomato and dried fish in Burkina Faso and assess the health risk of these elements. Two hundred twenty-two samples were collected and analyzed by atomic absorption spectrometry. The health risk assessment was based on the United States Environment Protection Agency (USEPA) model. Iron and Zinc were the elements with the highest concentrations in the investigated foodstuffs. The iron highest median value (68.80 mg/kg) was observed in dried fish followed by maize (43.09 mg/kg) and peanuts (28.92 mg/kg). Rates of 77.95%, 66.66% and 32.5% obtained respectively fro tomato, maize and rice samples were above the maximum limit of lead set by Codex Alimentarius while 47.6%, 71.16% and 0% of maize, tomato and rice samples respectively have shown concentration above the maximum limit of cadmium. Chromium had shown higher contribution rate to the maximum daily intake of 167.11%, 34%, 2% and 8.53% for rice, maize and peanut respectively. A non-cancer risk situation has been observed on rice, maize and peanut consumption. None of the index risk values was above the threshold set by USEPA.


Assuntos
Metais Pesados , Oryza , Oligoelementos , Animais , Burkina Faso , Monitoramento Ambiental , Ferro/análise , Metais Pesados/análise , Oryza/química , Medição de Risco , Oligoelementos/análise
20.
Environ Sci Pollut Res Int ; 29(29): 44954-44969, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35143004

RESUMO

As carbon peaking and carbon neutrality have become a global consensus, more and more countries have introduced relevant policies to adapt to their own countries and formulated corresponding time roadmap. The industrial sector, especially the steel sector, which produces high levels of pollution and carbon emissions, is facing significant pressure to transform its operations to reduce CO2 emissions. Previous studies have shown the importance of financial development (FD) in environmental protection; however, the impact of FD on the CO2 emissions of the steel sector is ignored. This paper examines the impact of FD on the CO2 emissions of the iron and steel industry from a global perspective using comprehensive panel data from a total of 30 countries during the period from 1990 to 2018. Empirical results show that an improved level of FD in a given country reduces the CO2 emissions of the iron and steel industry. The mechanism analysis indicates that FD promotes the upgrading of the structure of the iron and steel industry and the reduction of the CO2 emissions by means of the three-stage least square method. Our results also show that the effect of FD on reducing the CO2 emissions of the iron and steel industry in developing countries is less than its effect in developed countries. Estimation results also show the existence of the environmental Kuznets curve hypothesis in the iron and steel industry. Finally, we discuss the policy implications of achieving carbon neutrality in the steel sector.


Assuntos
Poluentes Atmosféricos , Aço , Poluentes Atmosféricos/análise , Carbono/análise , Dióxido de Carbono/análise , Desenvolvimento Econômico , Ferro/análise , Aço/análise
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