Plasma Optical Emission Spectrometry Research Articles

Copper-Based Metal–Organic Framework: Synthesis, Characterization and Evaluation for the Hydrogenation of Furfural to Furfuryl Alcohol

AbstractA novel Cu-MOF was synthesized at room temperature from commercially available and inexpensive reagents. The pre-catalyst was characterized using X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, inductively coupled plasma-optical emission spectroscopy, Fourier transform-infrared spectroscopy, powder X-ray diffraction, Brunauer-Emmet-Teller (BET) and scanning electron microscopy-energy dispersive X-ray spectroscopy. The Cu-MOF was characterized as microporous material with BET surface area and pore volume of 7.47 m2/g and 0.27 cm3/g, respectively, and is stable in most solvents. The MOF was evaluated as a heterogeneous catalyst for the hydrogenation of furfural to furfuryl alcohol (FA). Cu-MOF exhibited a high conversion of FF (76%) with selectivity towards FA (100%) at 140 °C, 50 bar for 24 h. The MOF was reused four consecutive times with a loss in catalytic performance. The decrease in catalytic activity could be attributed to the formation of inactive Cu(0) as revealed by HR-TEM and XPS studies. The HR-TEM of spent Cu-MOF showed a uniform particle size diameter of 3.5 nm. This work is significant in providing new strategies for the design and fabrication of highly selective MOF catalysts for the FF upgrading.

Characterization of Traditional Pottery Artifacts from Yucatán Peninsula, México: Implications for Manufacturing Process Based on Elemental Analyses

The present work is focused on developing and implementing a minimally invasive methodology for material characterization of traditional pottery from Yucatan, México. The developed methodology, which combines elemental (X-ray fluorescence spectroscopy (XRF), inductively coupled plasma-optical emission spectroscopy (ICP-OES), and Laser-Induced Breakdown Spectroscopy (LIBS)) and molecular (fiber optic reflectance spectroscopy (FORS)) spectroscopic analytical techniques, allowed for the characterization of contemporary pottery objects manufactured following traditional recipes in the town of Uayma, Yucatán, México and raw materials associated with the pottery manufacturing process. The results allowed us to detect and estimate the number of selected elements and helped to infer the presence of complex materials such as iron oxides, aluminosilicates, and calcium carbonate. Additionally, the analysis indicated two pottery groups separated by their elemental and molecular composition, corresponding to the sources of raw materials employed by the potters. It confirmed the absence of toxic compounds in ceramic objects, a significant concern for potters, as some objects are intended for domestic use. The research findings provide reassurance about the safety of these products.

Chemical composition, mutagenicity, and cytotoxicity of urban submicron particulate matter (PM1) in Agra, India

This study, conducted in Agra, India, examined the mass concentrations, chemical compositions, and seasonal variations of submicron particles (PM1). The concentrations of metals, water-soluble inorganic ions (WSIs) including anions (F−, Cl−, NO₃−, SO₄2−) and cations (Ca2+, K+, Mg2+, NH₄+, Na+), organic carbon (OC) and elemental carbon (EC) and polycyclic aromatic hydrocarbons (PAHs) in PM1 extract were determined using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), Ion Chromatography, Thermogravimetric Analysis and Gas Chromatography-Mass Spectrometry (GC–MS) respectively. For morphological observation of PM1 particles, Field Emission Scanning Electron Microscopy-Energy Dispersive X-ray spectrometry (FESEM-EDS) was used. The annual average concentration of PM1 was 82.9 ± 33.4 μg/m3, which exceeds the World Health Organisation's (WHO) safe limit for PM2.5 of 5 μg/m3 by a factor of 17. The PM1 mass composition included metals (31 %), WSIs (28 %), OC and EC (9.8 %), and PAHs (0.4 %). Winter recorded the highest PM1 concentration (96.1 ± 25.8 μg/m3), followed by post-monsoon, summer, and monsoon seasons. The average concentration of PAHs was 364.6 ± 226.6 ng/m3. Positive Matrix Factorization (PMF) identified traffic, emissions from biomass/coal and wood combustion, industrial/stationary sources, and secondary aerosols as potential contributors. The Ames test revealed the presence of frameshift mutations and base pair substitutions, especially in winter and post-monsoon. Additionally, PM1 exhibited cytotoxic effects on V-79 cells, with heightened toxicity during winter and prolonged exposure in other seasons. This study underscores the urgent need to address local emission sources and establish regulatory standards for PM1 in urban areas.

ICP-OES analysis of Lithium in honey, royal jelly, bee bread, propolis, and bees following microwave-assisted sample preparation

AbstractLithium is a natural, ubiquitously-occurring alkali metal found in varying amounts in foods like honey. Recently, lithium chloride (LiCl) was described to be effective against varroosis, a parasitic disease leading to loss of honey bee colonies with limited therapy options. However, LiCl treatment is not currently authorized for use in honey bee colonies. Such treatment might result in elevated lithium amounts in honey. To address this, a robust method for quantifying lithium in honey was validated using a microwave-assisted digestion technique combined with Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES), achieving detection levels as low as 0.151 mg/kg. The method was applied to 65 commercially available, randomly chosen honey samples, all of which had lithium levels below the limit of quantitation (LOQ). Furthermore, the method was successfully adapted for use with more complex bee matrices, including royal jelly, bee bread, propolis, and whole bees.

Quantification of selected heavy metals through inductively coupled plasma-optical emission spectrometry in containers of yogurts used in Erbil City, Krg, Iraq

Heavy metals are recently introduced in the manufacturing of various household utensils. The objective of this study was to investigate different heavy metals contents in the composition of yogurts containers collected from the markets of Erbil City. The collected containers were aluminum containers and plastic containers with several colors. An inductively coupled plasma optical emission spectrometer was used to analyse the contents of nine heavy metals including cadmium, cobalt, chromium, copper, iron, lead, manganese, nickel, and zinc. The level of total detected metal load found in the analyzed containers. The recorded level for total detected metal load in the overall aluminum containers sample was very high and approximately 27 times more than that level in the overall plastic containers sample. Lead and cadmium were known as toxic heavy metals and detected with a high amount in the aluminum containers composition. The total contamination in the aluminum containers composition was noticeably exceeded the permissible world limits for heavy metals in packaging materials. Results obtained clarified that the white color of plastic containers is more preferable and safer than the dark or other multi-color plastic containers items in terms of heavy metals. KEY WORDS: Aluminum and plastic container, Heavy metal, ICP-OES, Yogurt Bull. Chem. Soc. Ethiop. 2024, 38(6), 1509-1519. DOI: https://dx.doi.org/10.4314/bcse.v38i6.1

Assessment of heavy metal levels in cow's milk and associated health risks in the vicinity of the MIDROC Laga Dambi gold mine in Ethiopia

IntroductionThe possible health effects of consuming milk contaminated with heavy metals have been the subject of considerable concern worldwide. ObjectiveThe aim of this study was to determine the level of heavy metals in cow's milk in the vicinity of MIDROC Laga Dambi gold mine and to assess their possible health risks for consumers. MethodsNine composite samples were formed by aggregating 243 milk samples obtained in triplicates from 81 domestic milk-producing households. Inductively coupled plasma-optical emission spectroscopy was used to measure the amount of heavy metals after samples digestion under optimal conditions. ResultsThe heavy metals concentrations obtained were 13.913˗7.843, 9.505˗3.589, 5.972˗3.147, 2.288˗1.851, 0.403˗0.143, 0.436˗0.128, 0.26˗0.153, 0.143˗0.048, 0.160˗ND (not detected), and 0.140˗ND mgkg−1for Fe, Zn, Pb, Mn, Hg, Cr, Cd, As, Ni, and Co, respectively. Of the heavy metals identified, the levels of Pb, As, Cd, and Hg exceeded the recommended value. Based on the estimated daily intake (EDI), the total health quotient (THQ) is higher than unity even for Pb alone. It has been found that the consumption of cow milk increases the health index (HI) by 2.972. Ninety five percent of the HI in the study area was explained by the toxic heavy metals (Pb, Cd, As, and Hg) in the cow milk, which were found to be beyond the safe limit. ConclusionThis demonstrates that there is a health risk to the population who consume cow’s milk sourced from the vicinity of MIDROC Laga Dambi gold mine. To safeguard the public’s health, we advised strict monitoring and legislative control for the safety of cow’s milk originating from study area.

Study on the homologous effects on the performance of alkali metal-doping MgO-based adsorbents for CO2 capture

In this article, MgO-based adsorbents with different structure and surface property were prepared by combustion of the colloids containing Mg and alkali metal. At the same time, CO2 adsorption performance tests are conducted to compare the doping effect of alkali metal on MgO adsorbents. As confirmed, the introduction of lithium, sodium, and potassium can reduce the grain size of MgO and enhance the basicity, especially increasing the concentration of oxygen vacancies on MgO surface which exposed more basic adsorption active sites and was more conducive to CO2 adsorption. Among them, the one doped with 0.5 % K which had more electron shell numbers showed larger surface area and smaller crystal size. Most importantly, it provided more number of basic sites along with the improved strength of surface basicity due to the more oxygen vacancies. As a result, the maximum CO2 uptake (1.09 mmol/g) at the adsorption time of 60 min can be obtained which still remained at 0.67 mmol/g after 16 cycles of CO2 adsorption–desorption. With the aid of N2 physical adsorption, inductively coupled plasma-optical emission spectroscopy, powder X-ray diffraction, scanning electron microscope, X-ray photoelectron spectroscopy, electron paramagnetic resonance, and chemical adsorption, the relationship between CO2 adsorption capacity of MgO-based adsorbent and homologous regularity of alkali metal was disclosed. In other words, by comparing the CO2 adsorption performance of MgO adsorbents prepared by doping different alkali metals, CO2 adsorption capacity increased with the increase of electron shell numbers. Such a configuration is in favor of the electron supply of the p-orbitals and weakens the Mg–O bonds which promoted the formation of oxygen vacancies. The found will provide in-depth understanding for the modification and performance improvement of MgO-based adsorbents.

Mechanism of Improving Etching Selectivity for E-Beam Resist AR-N 7520 in the Formation of Photonic Silicon Structures

The selectivity of the reactive ion etching of silicon using a negative electron resist AR-N 7520 mask was investigated. The selectivity dependencies on the fraction of SF6 in the feeding gas and bias voltage were obtained. To understand the kinetics of passivation film formation and etching, the type and concentration of neutral particles were evaluated and identified using plasma optical emission spectroscopy. Electron temperature and electron density were measured by the Langmuir probe method to interpret the optical emission spectroscopy data. A high etching selectivity of 8.0 ± 1.8 was obtained for the etching process. The optimum electron beam exposure dose for defining the mask was 8200 pC/m at 30 keV.

Evaluation of iron speciation reference materials by wavelength-dispersive X-ray fluorescence, inductively coupled plasma optical emission spectroscopy, and flame/graphite furnace atomic absorption spectrometry for palaeoredox analysis

Fe speciation is crucial for distinguishing various redox conditions and thus offers valuable insights into the evolution of life and the environment throughout geological history. Monitoring experimental processes using reference materials is essential to ensure the consistency and reliability of Fe speciation analyses across laboratories. In this study, we evaluate the extraction processes and analytical methods used in the analysis of Fe speciation in four marine shale reference materials (WHIT, KL133, KL134, and BHW). A simple and feasible extraction process to extract Fecarb, Feox, and Femag that enables the simultaneous horizontal shaking of multiple samples by securing centrifuge tubes in foam racks is evaluated. Additionally, we compare the effects of the heating method on the extraction of FeR by heating the solution with a boiling water bath and a Bunsen burner. A new droplet method is devised for the instrumental analysis of Fe speciation using samples with high concentrations of total dissolved solids and organic matter matrices using wavelength-dispersive X-ray fluorescence spectrometry. A specialized PTFE support holder is designed to dry the filter paper in situ during sample preparation. We also compare figures of merits of wavelength-dispersive X-ray fluorescence spectrometry (WD-XRF), inductively coupled plasma-optical emission spectroscopy, and flame/graphite furnace atomic absorption spectrometry, including sample preparation, accuracy, precision, method limit of quantification, and linear range. The proposed WD-XRF droplet method will greatly simplify the sample preparation process and improve the efficiency of Fe speciation analysis.

Uncovering sediment pollution sources: A comparative assessment of two South African Estuaries

Richards Bay Harbour is South Africa's largest and busiest deep-water port by tonnage, and this ongoing shipping and port activities will expectedly result in metal contamination issues. The adjacent Mhlathuze Estuary is a nature reserve with a long history with Richards Bay Harbour and may be prone to metal contamination from multiple sources. The study investigates the sources of contaminated sediments in these two South African estuaries arising from their proximity to various anthropogenic activities. Investigating these sources of contamination is crucial for developing effective pollution control strategy since Richards Bay Harbour and Mhlathuze Estuary are regarded as estuaries of national conservation importance in South Africa. To provide further insights, sediment samples were acid digested and quantified for metal concentrations using Inductively coupled plasma-optical emission spectrometry (ICP-OES). Multivariate (SIMPROF and cluster) analysis was used to identify how sampling sites in Richards Bay Harbour and Mhlathuze Estuary were grouped based on sediment metal concentrations. Results of pollution load index for Richards Bay Harbour showed site 4 to be heavily polluted, while site 3 in Mhlathuze Estuary showed moderate pollution. Multivariate analysis (SIMPROF and cluster) further revealed sites related to anthropogenic activities and those that were unpolluted. Engaging this advanced analysis enhanced the ability to delineate potential pollution sources and further helped in the identification of the main contributors to sediment pollution. The findings indicate that port and industrial activities are the major contributors to sediment contamination at the estuaries. The results provide specific insights into the sources of pollution, informing targeted environmental management and policy-making efforts to protect and improve the estuarine environments.

Modeling and simulation for the sustainable recovery of aromatics (BTX) from petrochemical industrial wastewater.

Petrochemical wastewater is a major industrial source of pollution that produces a variety of toxic organic and inorganic pollutants, naturally present or added during the process. These pollutants are a serious threat to the soil, water, environment, and human being due to their complex and hazardous nature. Glycols such as monoethylene glycol (MEG), diethylene glycol (DEG), triethylene glycol (TEG), and aromatics (BTX-benzene, toluene, and xylene) are the most common organic impurities present in petrochemical wastewater. The objective of this paper is to recover aromatics and water from petrochemical industrial wastewater. The reclamation process is used to remove inorganic impurities such as heavy metals Fe, Zn, Pb, Mn, Al, Ni, As, Cr, Cu, Cd, and K and salts. In the present work, 1% sodium bi-carbonate (NaHCO3) is used to precipitate the inorganic impurities present in the wastewater at 40°C atmospherically. Aspen Hysys simulation software is used for modeling and simulation for the treatment process using NRTL (non-random-two-liquid) thermodynamic model. The process generated from Aspen Hysys is validated with lab experiments. To support global sustainable development, this study is focused on reducing, reusing, and recycling separation techniques such as centrifuge separation and vacuum distillation have been used. The characterization of regenerated water was performed using ICP-OES (inductively coupled plasma-optical emission spectroscopy) to determine the reduction in heavy metals. It was found that > 99.5% of heavy metals were removed. The regeneration of these aromatics is necessary for economic and environmental reasons so that it can be reused to avoid its disposal in and contamination of natural environments.

Elemental composition of post-wildfire biomass ashes and partly burned woody species in Bohemian Switzerland National Park, Czech Republic.

The study explored the post-wildfire elemental composition of parts (wood, bark, branch, cone, trunk, litter, twig, needle, sward, fallow, sapling, etc.) and by-products (biomass ashes, partly burnt parts, and char) of different woody species in the Bohemian Switzerland National Park, Czech Republic, and considered their effects on soils. Multi-elemental analysis of the fire by-products of the woody species was determined with inductively coupled plasma-optical emission spectrometry and mass spectrometry and compared with control biomass samples unaffected by wildfire. Most fire by-products were slightly alkaline, with acidic ashes obtained from blueberry wood. The by-products of the wildfire were characterized by varied total contents of macro (P, Ca, K, Mg, and S), micro (Na, Mn, Fe, Cu, and Zn), and other elements (B, Co, Mo, and V) vital to soil fertility and plant growth. The mean content of macro elements in the biomass ashes was up to 4.16 P, 23.5 Ca, 2.48Mg, 63K, and 5.57 S g kg-1. These values were comparatively lower than published data for ashes obtained under optimized conditions, e.g., those combusted in power generation facilities. Conversely, partly burnt parts-an indication of incomplete combustion-had higher 9.22 P, 79 Ca, and 5.99Mggkg-1 contents in spruce needles than in biomass ashes and the control. Variations in woody species and anthropogenic activities in areas of wildfires produced varied As, Cd, Cr, Ni, and Pb contents above EU fertilizer regulation. Caution in applying biomass ashes from wildfires on fields is required due to risk/toxic elements input from anthropogenic activities. Wildfire effects on the elemental composition of woody species can provide information on plant parts most suitable for biomass ashes for soil and ecosystem safety.

Potentially toxic metals in Northeast Ethiopian agricultural soils: implications for Solanum lycopersicum (Tomato) production and human health.

Exposure to heavy metal-contaminated vegetables, irrigation water and agricultural soil is one of the most challenging environmental issues worldwide. This study aimed to evaluate the health effects of potentially toxic metals (PTMs) including Cr, Cd, Fe, Pb, Cu, Zn, and Co from agricultural soil, irrigation water, and tomato plants collected from the Abuarie irrigation site, Northeast Ethiopia. The samples were digested using acid digestion method, and its concentration was quantified using Inductively Coupled Plasma-Optical Emission Spectroscopy. The concentrations of PTMs in the soil, tomato, and irrigation water samples ranged from 49,020 ± 275 (Fe) to 11.85 ± 0.44 (Cd), 170 ± 1.98 (Fe) to 0.29 ± 0.006 (Cd) mgkg-1, and 0.24 ± 0.003 (Fe) to 0.025 ± 0.005(Ni)mgL-1 , respectively. The results revealed Zn, Ni, Cd and Cr in soil, all metals in tomato, and Cu, Ni, Cd and Pb in irrigation water sample were above the World Health Organization threshold values. Moreover, the separate and cumulative exposure to farm soil, irrigation water, and consumption of tomato were investigated using the hazard quotient (HQ) and hazard index (HI) values, respectively. The results revealed that individual exposure to each sample type did not have a significant impact on health (HQ < 1). However, simultaneous exposure to all of the sample types (soil, tomato and irrigation water) at the same time had a high likelihood of affecting health (HI > 1). The total carcinogenic concentrations of Cr, Cd, Ni, and Pb were greater than 1 × 10-4, revealing that farmers have a high probability of developing cancer during their lifetime. Minimizing simultaneous exposure to soil, tomato, and irrigated water for local people is highly recommended to prevent the risk of PTMs.

Assessing Elemental Diversity in Edible-Podded Peas: A Comparative Study of Pisum sativum L. var. macrocarpon and var. saccharatum through Principal Component Analysis, Correlation, and Cluster Analysis

This study assessed eleven elements in 24 edible-podded peas, including sugar snap pea and snow pea genotypes aiming to identify promising parents for nutraceutical breeding. Elemental concentrations of pods (dry weight basis) were estimated through inductively coupled plasma-optical emission spectroscopy (ICP-OES). The ranges for these elements varied significantly, highlighting the diverse elemental profiles within the edible-podded pea genotypes. All the elements exhibited a high genotypic and phenotypic coefficient of variation along with considerable heritability and hereditary progress. Positive and significant correlations were recorded among all elements, suggesting the potential for simultaneous selection for these traits. Principal component analysis (PCA) revealed that the first two components accounted for 80.56% of the variation. Further, cluster analysis, based on Euclidean distance, grouped the 24 cultivars into two major clusters. Cluster I exhibited higher means for all estimated concentrations compared to Cluster II. Notably, Dwarf Grey Sugar and Arka Sampoorna from the snap pea group and PED-21-5 and Sugar Snappy from the sugar snap pea in Cluster II demonstrated superior elemental concentration in whole pods. The selected edible-podded pea genotypes serve as valuable genetic resources for new cultivar development, particularly in biofortification efforts targeting whole pod nutrient composition.

Contrasting metal bioaccumulation in marine benthic invertebrate groups in polluted harbor sediments

This study examined the sediment metal fractions and availability to infer bioaccumulation in marine harbor benthic organisms. Total metals were analyzed using atomic absorption spectrometry and inductively coupled plasma-optical emission spectrometry for chemical fractions and organisms. The results showed similar metal concentrations and distribution driven by rivers and harbor pollution. We found significant differences in metal accumulation in marine benthic groups, highest in scavenger species. Their metal concentrations in decreasing order were 1.97–4568, 0.10–1260, 1.64–159, and 0.105–112 μg g−1 dw for hermit crabs, forams, bivalves, and polychaetes. Moreover, certain organisms, such as tusk shells, sea pens, bivalves, forams, and isopods, may exhibit selective metal accumulation. Biota-sediment accumulation factors (>1) were highest for essential metals like Cu, Zn, and Mn, while toxic metals like As, Cr, Co, and Ni increased. This concurrent assessment provides more comprehensive data for metal bioaccumulation in marine benthic ecosystems.

Chitosan-stabilized gold nanoparticles decorated with a thiodiacetic acid nanoprobe for selective detection of arsenic(iii) in rice and water samples.

A sensitive and selective method for the detection of arsenic(iii) (As3+) based on chitosan-stabilized gold nanoparticles (CS/AuNPs) decorated with a 2,2'-thiodiacetic acid (TDA) nanoprobe was developed and used to detect and indicate the contamination of rice, drinking water and environmental water samples. AuNPs were reduced and stabilized with CS and subsequently functionalized with TDA. As3+ interacted with the carboxylate group of TDA to form an As-TDA complex, inducing the aggregation of CS/AuNPs@TDA. The aggregation of CS/AuNPs@TDA was accompanied with a change in color from red to bluish purple and a shift in surface plasmon resonance wavelength from 525 nm to 645 nm. The response for the detection of As3+ was linear at concentrations from 10 to 1000 μg L-1 with a limit of detection of 6.1 μg L-1. The method exhibited selectivity toward As3+ among various cations (As5+, Cu2+, Fe3+, Fe2+, Hg2+, Al3+, Cr3+, Cd2+, Co2+, Ni2+, Pb2+ and Zn2+) and anions (Br-, Cl-, F-, SO4 2-, NO3 - and PO4 2-). The CS/AuNPs@TDA nanoprobe was applied to detect As3+ in rice, drinking water and environmental water samples. The results were consistent with those obtained via inductively coupled plasma-optical emission spectrometry (ICP-OES). Satisfactory recoveries ranging from 88.22% to 105.74% (RSDs of 0.25-2.99%) were obtained from spiked samples.

Correlation between serum heavy metals and the risk of oral squamous cell carcinoma and oral potentially malignant disorders

Oral squamous cell carcinoma (OSCC) is a serious public health problem in various Asian countries, including Sri Lanka, and a combination of cultural practices, lifestyle factors, and genetic predispositions influences the incidence of these cancers. The examination of the connection between exposure to heavy metals and the probability of developing oral potentially malignant disorders (OPMD) and OSCC has been limited in its scope, and the overall consequences of such exposure remain largely unknown. This study aims to clarify the link between serum levels of heavy metals and the risk of OSCC and OPMD. The concentrations of seven heavy metals—namely, arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), lead (Pb), and zinc (Zn)—were analyzed in serum samples from 60 cases and 15 controls in the Sri Lankan cohort. The Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) was used for the analysis. Subsequently, the data underwent statistical evaluation via the Kruskal–Wallis H test, using the Statistical Package for Social Sciences (SPSS) version 28 software, with a confidence interval set at 95%. A p-value less than 0.05 was considered statistically significant. The cohort consisted of 48 men and 27 women, with 15 patients each diagnosed with OSCC, OSF, OLK, and OLP, and 15 healthy controls. The study used the Kruskal–Wallis Test to compare metal concentrations across groups, finding significant differences for all metals except As and Pb. Significant associations were observed between age, past medical history, drug history, gender, smoking, alcohol consumption, and betel chewing. The Spearman Correlation test showed significant correlations between the concentrations of Cr, Co, Cu, As, and Zn and the presence of cancer/precancer conditions. The study’s findings suggest that heavy metal contamination may be linked to the development of OSCC and precancerous conditions. When comparing OSCC and OPMD cases with controls, the serum concentrations of As and Pb did not differ significantly. However, Cd, Cr, Co, Cu, and Zn exhibited significantly higher concentrations among cases compared to controls (p < 0.05). This study observed significant variations in the levels of these five heavy metals among cancerous (OSCC), premalignant (OPMD), and healthy tissues, suggesting a potential role in the progression of malignancies. These findings underscore the importance of environmental pollution in this specific context.

Re-designing nano-silver technology exploiting one-pot hydroxyethyl cellulose-driven green synthesis.

Re-designing existing nano-silver technologies to optimize efficacy and sustainability has a tangible impact on preventing infections and limiting the spread of pathogenic microorganisms. Advancements in manufacturing processes could lead to more cost-effective and scalable production methods, making nano-silver-based antimicrobial products more accessible in various applications, such as medical devices, textiles, and water purification systems. In this paper, we present a new, versatile, and eco-friendly one-pot process for preparing silver nanoparticles (AgNPs) at room temperature by using a quaternary ammonium salt of hydroxyethyl cellulose (HEC), a green ingredient, acting as a capping and reducing agent. The resulting nano-hybrid phase, AgHEC, consists of AgNPs embedded into a hydrogel matrix with a tunable viscosity depending on the conversion grade, from ions to nanoparticles, and on the pH. To investigate the synthesis kinetics, we monitored the reaction progress within the first 24h by analyzing the obtained NPs in terms of particle size (dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM)), Z-potential (ELS), surface plasmon resonance (UV-VIS), crystallographic phase (XRD), viscosity, and reaction yield (inductively coupled plasma-optical emission spectrometry (ICP-OES)). To explore the design space associated with AgHEC synthesis, we prepared a set of sample variants by changing two independent key parameters that affect nucleation and growth steps, thereby impacting the physicochemical properties and the investigated antimicrobial activity. One of the identified design alternatives pointed out an improved antimicrobial activity in the suspension, which was confirmed after application as a coating on nonwoven cellulose fabrics. This enhancement was attributed to a lower particle size distribution and a positive synergistic effect with the HEC matrix.

Novel Microwave Assisted-Hydrogen Peroxide Digestion of Coal and Fuel Oils Using Methionine as a Capping Reagent for the Determination of Mercury by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES)

A novel analytical method was developed for quantifying total mercury in fuel oils using methionine as a capping reagent. Methionine was added to fuel and standard solutions as a preserving agent before microwave-assisted hydrogen peroxide digestion (MW-AHPD). To the best of our knowledge, it is the first-time methionine was used as a capping reagent for the total determination of mercury in fuel oils using ICP-OES with a pneumatic nebulizer. Multivariate optimization tools (two-level half factorial and central composite design) were used to investigate the most influential parameters of the MW-AHPD method. The best conditions were 0.1 g sample mass, 5 mol L−1 [H2O2], 5. 95 mol L−1 [methionine], 36 min and 200 °C with accepted trueness (93–107%) and precision (1.94%). The developed MW-AHPD procedure provided a coefficient of determination (R2) of 0.9989, limit of detection (LOD) of 0.25 µg L−1 and limit of quantification (LOQ) of 0.8 µg L−1. The newly developed MW-AHPD procedure was validated using hydride generation-ICP-OES and there was no statistical difference at 95% confidence level between the newly developed method and the standard protocol. Therefore, the newly developed MW-AHPD procedure was applied with coal, crude oil, gasoline, diesel oil, and kerosine samples and the concentration levels were from 0.876 ± 0.023 to 0.938 ± 0.082 µgg−1, 0.383 ± 0.043 to 0.506 ± 105 µgg−1, 0.306 ± 0.010 to 0.390 ± 0035 µgg−1, 0.360 ± 0.003 to 0.431 ± 0.001 µgg−1 and < DL, respectively.

Potential human health risk assessment associated with Hg, Cd, Pb, and As in sardines and shrimp from four Egyptian coastal governorates

Heavy metal contamination in seafood is a developing concern due to the potential negative consequences on human health. Egypt's coastal regions are important for seafood production and consumption, making it critical to assess the safety of these aquatic resources. The current study examined toxic metal levels (Hg, Pb, Cd, and AS) in 96 samples of sardine and shrimp from four Egyptian coastal governorates (Alexandria, Kafr El-Sheikh, Damietta, and Port Said) from 2019 to 2021. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) was used to investigate the four hazardous metals. The recovery percentages of the determined metals ranged between 97 % and 99 %. Limits of detection (LOD) and limit of quantification (LOQ) for the determined metals ranged from 0.001 to 0.0077 mg/l and from 0.0035 to 0.026 mg/l, respectively. Mercury (Hg) was not found in any of the samples tested. The concentrations of Pb and Cd in the sardines and shrimp samples were higher in the winter seasons than in the summer seasons. Meanwhile, the difference in seasons had no effect on the concentration of As in the sardines and shrimp samples. The highest concentrations of the other three metals in the sardine and shrimp samples were used to calculate the Estimated Daily Intake (EDI), Target Hazard Quotient (THQ), and Hazard Index (HI). The obtained THQ as well as the HI of Pb, Cd, and As were all less than 1.0 (with the exception of sardine samples from Kafr El-Sheikh Governorate, which recorded 1.262), indicating that there is no significant health risk to the consumer from consuming such sardines and shrimp from these governorates. The effect of different seasons on the concentrations of the metals under study does not have a specific behavior, but varies according to the governorate, the type of sample, and the type of contaminated metal. Due to the high level of contamination with heavy metals in sardine samples collected from Kafr El-Sheikh governorate (TTHQ = 1.26), an environmental study is required to determine the causes of contamination and control them.