Manganese Content Research Articles

The effect of manganese and carbon on the mechanical properties of the welded layer of the bucket teeth of the Hadfield steel excavator

The paper investigates the effect of the surfacing composition’s chemical structure (the manganese and carbon concentrations’ ratio) on the mechanical properties of the surfacing layer on Hadfield steel for increasing the durability of the products made from it, namely the excavator bucket’s teeth. Two criteria, namely the impact toughness and wear resistance of the coating, were chosen as optimization parameters. The assessment of the impact strength of the deposited coating was carried out on the Sharpie samples on the pendulum copra, and the wear test was carried out according to the Brinly-Haworth scheme in the conditions of samples’ abrasion with quartz sand. Wear resistance of Hadfield steel, containing 1.1% C and 13% Mn, was taken as a unit of wear resistance in these experiments. To determine the optimal coating modes, the active experiment with the application of mathematical planning methods was conducted. The obtained response surfaces and graphs of equal output lines make it possible to establish the level of studied factors’ influence on the optimization parameter. In order to analyze the influence of given factors on the optimization criteria, scatter plots with histograms were constructed, which make it possible to determine the rational values ​​of the selected optimization criteria graphically - impact toughness and wear resistance of the coating

Welding techniques and manganese concentrations in blood and brain: Results from the WELDFUMES study

This study used whole-brain mapping to investigate the effect of different welding processes on manganese (Mn) accumulation in the brain. Exposure measurements were performed at the welders’ workplaces about 3 weeks before a magnetic resonance imaging (MRI) examination. The welders were categorized into three main groups based on welding method, and the T1-relaxation rate (R1) was measured using quantitative MRI (qMRI). Welders using shielded metal arc welding (SMAW) were found to have lower accumulations of total Mn in clusters encompassing white matter, thalamus, putamen, pallidum, and substantia nigra compared with welders using inert gas tungsten arc welding (GTAW) or continuous consumable electrode arc welding (CCEAW). A positive correlation was found between Mn in red blood cells (Mn-RBC) and R1 in a region encompassing pre-and post-central gyri. The results of this study show that the accumulation of free, bound, or compartmentalized Mn ions in the brain differed depending on the welding method used. These differences were predominately located in the basal ganglia but were also found in regions encompassing white matter. The level of Mn-RBC was correlated to the deposition of Mn in the left primary somatosensory and motor cortex and may therefore be linked to neurological and neurobehavioral symptoms.

Assessment of Essential Trace Elements Cu, Zn, Mn, and Ni in Mediterranean Mussels (Mytilus galloprovincialis) from the Algerian Coast.

The aim of this study was to determine the levels of essential trace elements copper, zinc, manganese, and nickel in two size groups of mussels, Mytilus galloprovincialis, sampled from three sites along the Algerian coast with different levels of pollution. The results of this work are very interesting for determining the effect of mussel size on the variation of contaminant levels in environmental monitoring studies. Thirty individuals from 2 size groups, less than 4-cm and more than 4-cm shell length, were collected over 4 seasons at each site studied. The samples were dissected, and copper, zinc, manganese, and nickel were measured in the whole soft tissues by inductively coupled plasma mass spectrometry (ICP-MS). The maximum concentrations of copper, zinc, manganese, and nickel expressed in mg/kg dry weight at the three sites were 54.01, 146.25, 20.69, and 8.85, respectively. A clear distribution pattern of the studied elements was observed in the two size classes. In fact, significantly higher concentrations (P < 0.05) were found in individuals with a shell length of less than 4 cm. Significantly, higher concentrations (P < 0.05) were found in individuals with a shell length of less than 4 cm due to their high filtration and low excretion activities compared to long individuals. In addition, metal pollution index (MPI) values were higher in small bivalve individuals. The trace element contents found in the mussel samples of the present study showed large spatial and temporal variations among the different sites studied, highlighting the typical exposure of marine sites to different marine pollutants. Notably, elevated concentrations of copper were observed in the port of Zemmouri, likely due to port activities. Conversely, the highest levels of manganese and nickel were recorded at Boudouaou El Bahri, potentially attributable to the use of fertilisers by agricultural activities. Some shellfish samples had exceeded the permissible concentration levels of copper and manganese, thereby posing a danger to bivalve consumers.

Prolonged Copper Supplementation Modified Minerals in the Kidney, Liver and Blood, and Potentiated Oxidative Stress and Vasodilation of Isolated Aortic Rings in Young Wistar Rats.

Previous studies have highlighted that copper supplementation at 200% of the recommended daily dietary allowance modified vascular contraction and relaxation through increased reactive oxygen species (ROS) and prostaglandin formation, which modified the antioxidant status of middle-aged Wistar rats. In this study, young (1 month old) male Wistar rats (n/group = 10) received a diet supplemented with 6.45 mg copper/kg (100% of daily recommendation-Group A) for 8 weeks. The experimental group received 12.9 mg copper/kg of diet (200% of the daily recommendation-Group B). Experimental supplementation with 200% copper modified the copper concentration in the blood (1.21-fold, p = 0.04), liver (1.15-fold, p = 0.032), and kidneys (1.23-fold, p = 0.045), potentiated the ROS formation in the aortic rings, and enhanced the sensitivity of the aortic rings to the vasodilator acetylcholine. We observed an increased participation of nitric oxide (NO) derived from inducible NO synthase (iNOS) in vascular contraction and a decreased net effect of vasodilator prostanoids derived from cyclooxygenase-2 in vascular relaxation. In rat kidneys, the concentrations of potassium (1.08-fold, p = 0.001) and iron (1.13-fold, p = 0.046) were higher, while, calcium (0.88-fold, p = 0.001) and chromium (0.77-fold, p = 0.005) concentrations were lower. In the rat liver, magnesium (1.06-fold, p = 0.012) was higher. No differences were observed in the concentrations of sodium, zinc, manganese, selenium, cobalt, molybdenum, and vanadium. The antioxidant activity of water- and lipid-soluble compounds; total antioxidant status in the blood; and superoxide dismutase, catalase, and malondialdehyde levels in the heart did not change. In young rats, prolonged supplementation with 200% copper had a lesser effect than anticipated on oxidative stress and vascular reactivity. Detailed data on the status of trace elements and their interactions in patients of different age groups are strongly required for effective nutritional and therapeutic intervention.

Assessment of produced water from oil and gas field Gujar Khan, Punjab, Pakistan

This study was conducted to analyze the physiochemical and heavy metal concentrations in produced water of Missa Kaswal Oil field Gujar khan, Punjab, Pakistan. Produced water samples were collected from various locations points and analyzed for various parameters by using standard operation procedures. According to Pakistan Environmental Protection Agency, pH, temperature was noted with in permissible limit, total dissolved solids, chlorides, fluorides and oil and grease concentrations were found very high. The concentration of chloride and oil and grease were found several times higher as compared to Pak-EPA. Heavy metals results of the research samples are compared with Pakistan Environmental Protection Agency. From the results it was found that nickel (Ni), lead (Pb), manganese (Mn), zinc (Zn) and arsenic (As0 were within the permissible limits while chromium (Cr) concentration was observed in produced water above the permissible limits. So overall study concluded that wastewater which is released from oil and gas sector is highly polluted. So, it is strongly recommended that Pakistan Environmental Protection Agency should regular check and monitor that wastewater before releasing into the environment.

Evaluation of Heavy Metal Concentration in Sediments of Rupingazi River, Kenya

Heavy metal concentration (Cu, Zn, Fe, Mn, Ni) was evaluated in sediment samples of Rupingazi river during the wet and dry seasons. In this study, the sediment samples were collected from twenty sampling points along the river. The heavy metal levels were evaluated using Atomic Absorption Spectrphotometer.The obtained data was analyzed using one-way analysis of variance. The range of the concentration of copper was found to be 4.68- 12.69 mg/kg for the wet season and 0.98-24.10mg/kg for the dry season. The mean values of the concentration of iron was found to be 1422-6145.33 mg/kg for the wet season and 1254-5866.67 mg/kg for the dry season. The range of the concentration of Nickel was found to be 0.72- 30.73 mg/kg for the wet season and 2.63-12.48 mg/kg for the dry season. Concentration of manganese was found to be 48.03-411.20 mg/kg for the wet season and 6.15-248.35 mg/kg for the dry season Zinc concentration was found to be 26.29-167.10 mg/kg for the wet season and 4.82-28.39 mg/kg for the dry season. The Zinc, Manganese, Nickel Iron and Copper levels were not beyond the USEPA recommended limits.

LC-MS-Based Targeted Metabolite Profiling and Atomic Absorption Spectrophotmeter Based Mineral Analysis of Methanol Extract of Terminalia bellerica (Gaertn.) Leaves

Aim: Natural products in medicinal plants are one of the important sources for modern drug discovery. Plant-based formulations play an important role in management of numerous diseases. To discover the medical potential of natural products, it is important to understand the bioactive compounds present in medicinal plants. Hence the aim of the study is to identify the volatile compounds by LC –MS analysis and minerals by AAS assay present in the leaves of Terminalia bellerica. Study Design: This study investigates metabolites present in leaves of Terminalia bellerica have been studied by AAS and LC-MS techniques. Results: The AAS assay showed that the leaves of T. bellerica are particularly rich in iron (260 mg/kg) compared to their zinc, manganese, and copper content. Meanwhile, the LC-MS analysis identified chebulinic acid, chebulagic acid, punicafolin, myricetin, rutin, and galloyl punicalagin as being present in the highest concentrations. Conclusion: Results highlighted presence of considerable amount of iron and other minerals in methanolic extract of the leaves of T. bellerica, it may be used in the development of health supplements. The results also revealed that bioactive compounds in the methanolic extracts of T. bellerica leave used for drug design and making it safe to human health.

The Indica Hybrid Rice Containing an OsNRAMP5 Knockout Exhibits Better Adaptability Compared to Its Paternal Parent in the Middle Reaches of the Yangtze River

OsNRAMP5 is a pivotal gene involved in the uptake and transport of cadmium and manganese in rice plants. While the knockout of OsNRAMP5 has significantly decreased cadmium accumulation in rice grains, its impact on the adaptability of indica hybrid rice and its paternal parent still needs to be more adequately explored. This study conducted a three-year field experiment with two of the OsNRAMP5 knockout lines (indica hybrid rice LYDG-1 and its paternal parent DG-1) and their wild-type at four distinct locations in the middle reaches of the Yangtze River. Their adaptability was evaluated by cadmium and manganese accumulation, yield traits, and grain quality. The findings reveal that OsNRAMP5 knockout lines, when grown in mildly and moderately Cd-contaminated paddies, exhibit significantly and stably lower cadmium and manganese accumulation compared with the wild-type. However, there were no significant differences in cadmium and manganese content between LYDG-1 and DG-1. Regarding yield traits, OsNRAMP5 knockout lines did not show a significant reduction compared with the wild-type, except for DG-1 in soil with lower manganese content. For grain quality, the quality of the appearance of OsNRAMP5 knockout lines significantly improved compared with the wild-type. However, the milling quality of DG-1 significantly reduced compared with the wild-type, while this negative impact for LYDG-1 was only observed in soils with lower manganese content. Overall, the indica hybrid rice with an OsNRAMP5 knockout exhibits better adaptability than its paternal parent in the middle reaches of the Yangtze River. These findings offer valuable insights into the potential application and promotion of OsNRAMP5 mutant rice varieties in the middle reaches of the Yangtze River.

Study of Various Rootstocks and Scion on Leaf Nutrient Status in Mango (Mangifera Indica L.)

The current experiment, entitled “Study of various rootstocks and scions on leaf nutrient status in mango (Mangifera indica L.)” The experiment was framed in RBD (Randomized Block Design) with three replications studied for leaf nutrient analysis. The combination of five rootstocks and three scions, was carried out in the Department of Horticulture (Fruit and Fruit Technology), Bihar Agricultural University, Sabour, Bhagalpur, Bihar, during 2020–21 to evaluate the best combination regarding leaf nutrient content. The appropriate rootstock allows sufficient intake of nutrients and movement while additionally allowing for lesser fertilizer treatment rates, decreasing the possibility of leaching nutrients and toxicity while preserving fruit quality and yield. The analysis of the experiment macronutrient data related to N: P: K content in the leaf of the scion with the influence of different rootstocks has been presented in Table 1. The highest percentage of nitrogen, phosphorus and potassium were observed respectively treatments i.e. T7: Zardalu grafted on Olour (1.62%); T9: Bombay Green grafted on Olour (0.19 %); and T15: Bombay Green grafted on Mahmood Bahar (0.76%), whoever the investigation of micronutrients (Cu, Fe, Mn, and Mg) in leaves of different treatments of rootstocks has been presented in Table 2. The maximum value of copper, iron, manganese and magnesium content of leaf was observed respectively in the treatments i.e. (T13) Zardalu when grafted on Mahmood Bahar (38.33 ppm), (T8) Zardalu grafted on Mylepalium (109.00 ppm), (T4) Zardalu grafted on Mylipalium (0.24 ppm) and (T4) Zardalu grafted on Mylepalium (0.24ppm).

Microplastic and heavy metal contamination in sediments of the high-altitude Nundkol Lake of northwestern Himalayas-Kashmir

This study investigates heavy metal and microplastic contamination in the sediment of Nundkol Lake, a high-altitude glacial lake in the northwestern Himalayas. Sediment analysis revealed heavy metal concentrations significantly exceeding background levels, with average concentrations of cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), zinc (Zn), and chromium (Cr) recorded at 40.991 ppm, 54.434 ppm, 87,843.59 ppm, 1544.566 ppm, 83.288 ppm, 16.312 ppm, 104.571 ppm, and 106.514 ppm, respectively. Notably, the highest levels of Cu, Fe, Mn, and Pb were observed in sample GL2, indicating potential local geochemical anomalies. The trace elements were quantified using a Graphite Furnace - Atomic Absorption Spectrophotometer (Perkin Elmer-PinAAcle 900AA) for high precision.Microplastic analysis revealed an average abundance of 76±12.08 items/kg dry weight, predominantly fibers. The microplastics were mostly red (55.26 %), blue (36.84 %), orange (5.26 %), and green (2.63 %). Raman spectroscopy identified Polyamides (PA) as the predominant type (86.5 %), with the remainder being Polyethylene (PE) and Polypropylene (PP). The results suggest tourism, fishing, and trekking activities as major contributors to microplastic presence. This study uniquely combines the assessment of heavy metal and microplastic contamination in a high-altitude lake, providing a comprehensive view of pollutant dynamics. The findings highlight the need for tailored mitigation strategies and comprehensive monitoring programs to protect this fragile region. Applications include informing environmental policy, guiding pollution mitigation efforts, and promoting sustainable tourism practices. This study offers valuable insights into the environmental health of high-altitude lakes and underscores the need for efforts to mitigate anthropogenic impacts.

Investigating the relationship of co-exposure to multiple metals with chronic kidney disease: An integrated perspective from epidemiology and adverse outcome pathways

Systematic studies on the associations between co-exposure to multiple metals and chronic kidney disease (CKD), as well as the underlying mechanisms, remain insufficient. This study aimed to provide a comprehensive perspective on the risk of CKD induced by multiple metal co-exposures through the integration of occupational epidemiology and adverse outcome pathway (AOP). The study participants included 401 male mine workers whose blood metal, β2-microglobulin (β2-MG), and cystatin C (Cys-C) levels were measured. Generalized linear models (GLMs), quantile g-computation models (qgcomp), least absolute shrinkage and selection operator (LASSO), and bayesian kernel machine regression (BKMR) were utilized to identify critical nephrotoxic metals. The mean concentrations of lead, cadmium, mercury, arsenic, and manganese were 191.93, 3.92, 4.66, 3.11, 11.35, and 16.33 µg/L, respectively. GLM, LASSO, qgcomp, and BKMR models consistently identified lead, cadmium, mercury, and arsenic as the primary contributors to kidney toxicity. Based on our epidemiological analysis, we used a computational toxicology method to construct a chemical-genetic-phenotype-disease network (CGPDN) from the Comparative Toxicogenomics Database (CTD), DisGeNET, and GeneCard databases, and further linked key events (KEs) related to kidney toxicity from the AOP-Wiki and PubMed databases. Finally, an AOP framework of multiple metals was constructed by integrating the common molecular initiating events (reactive oxygen species) and KEs (MAPK signaling pathway, oxidative stress, mitochondrial dysfunction, DNA damage, inflammation, hypertension, cell death, and kidney toxicity). This is the first AOP network to elucidate the internal association between multiple metal co-exposures and CKD, providing a crucial basis for the risk assessment of multiple metal co-exposures.

Joint effects of tobacco smoke exposure and heavy metals on serum sex hormones in adult males.

This study aimed to explore the associations of tobacco smoke exposure (TSE) and heavy metal exposure on sex hormones and the joint effects between them in adult males. The study used data of 2244 adult males from the National Health and Nutrition Examination Survey (NHANES, 2013-2016). Weighted linear regression models were used to calculate their beta (β) coefficients and corresponding confidence interval (95% CI), which assessed the joint effects of TSE and heavy metals on sex hormones. Sex hormone-binding globulin (SHBG) showed a positive association with increased per standard deviation (SD) for cotinine (β=0.024 [0.004, 0.043]; P<0.001), lead (β=0.021 [0.002, 0.039]; P=0.028), and cadmium (β=0.034 [0.015, 0.053]; P<0.001). Manganese was positively associated with estradiol (E2) (β=0.025 [0.009, 0.042]; P=0.002). The subjects with higher cadmium levels were more likely to have higher total testosterone (TT) (β=0.042 [0.023, 0.062]; P<0.001). TSE and lead exerted synergistic effects on TT (p for interaction = 0.015) and E2 (p for interaction = 0.009), as also did TSE and cadmium on SHBG (p for interaction = 0.037). Compared with the reference group, TSE participants who were exposed to high concentrations of lead, cadmium, mercury, and manganese had significantly elevated TT levels, but these high levels presented no significant association with E2 levels. A significantly higher level of SHBG among TSE participants was detected in high concentrations for lead, cadmium, and mercury. TSE exacerbated sex hormone imbalances when combined with high levels of metal exposure. Smoking cessation is crucial, especially in the case of high levels of occupational exposure to heavy metals.

Nutritional prospects and heavy metal risks in fattened versus wild mud crabs of the Ganges-Brahmaputra delta: Implications for sustainable management

Scylla olivacea, or the mud crab, is a crucial economic contributor in Southeast Asia, notably in the coastal region of the Ganges-Brahmaputra delta. This study compared the nutritional and heavy metals of fattened and wild-captured mud crabs from the southwest coastal areas of the Ganges-Brahmaputra delta, focusing on proximate composition, fatty acids, amino acids, and heavy metals. Fattened mud crabs showed higher crude protein levels (13.2%–14.4%), particularly in males, and higher crude fat and ash contents than their wild counterparts. Among fatty acids, fattened crabs had the highest palmitic acid levels (34.0%–41.2%), whereas wild crabs were rich in linoleic and linolenic acids. Amino acid analysis revealed that histidine and arginine were the most prevalent essential amino acids in fattened and wild crabs, respectively. Elemental analysis indicated that calcium levels were high in both groups. However, zinc, copper, iron, and manganese concentrations exceeded recommended dietary allowances. Furthermore, the wild mud crabs contained heavy metals lower than that of the fattened mud crabs. Notably, nickel, lead, and cadmium levels surpassed maximum permissible limits, suggesting potential health risks in fattened and wild mud crabs. The concentration of Omega-3 fatty acids was higher in wild crabs than in cultured ones. These findings emphasize the need for cautious consumption and strict monitoring in mud crab aquaculture to ensure food safety and sustainability.

Appraisal on heavy metal contamination in tissues (gills, intestine, liver, and fillet) of &lt;i&gt;Parachanna obscura&lt;/i&gt; and the physicochemical properties of Oguta Lake, South-Eastern Nigeria.

The aim of this study is to provide baseline data on the investigation of concentrations of copper (Cu), lead (Pb), iron (Fe), manganese (Mn), and zinc (Zn) in various tissues (gills, intestine, liver, and fillet) of Parachanna obscura in Oguta Lake, and to assess physicochemical properties of Oguta lake to determine level of pollution and contamination. Twenty fish samples in total were collected at the fishermen landing site of the lake and analyzed using the Atomic Absorption Spectroscopy (AAS). Dissolved oxygen and temperature were measured on site using dissolved Oxygen meter (model 5509) and Mercury-in-glass thermometer respectively, while other parameters were analyzed in the laboratory. Results indicated Fe had the highest concentrations (1.479±0.003 mg/kg) especially in the gills, while Mn recorded least concentrations (0.001±0.000) mg/kg) of all metals analyzed. Values for Cu (0.026±0.002 mg/kg), Mn (0.001±0.000 mg/kg), Zn (.782±0.015 mg/kg), and Fe (1.479±0.030 mg/kg) levels were within FAO/WHO permissible limits in all tissues, whereas Pb (1.438±0.015 mg/kg) exceeded standard limits especially in the gills and intestines, indicating potential contamination and threats to aquatic and human health. Heavy metal concentrations in the tissues followed the order: gills &gt; intestine &gt; fillet &gt; liver. The physicochemical properties assessment of Oguta Lake indicated a stable temperature with mean value of (28.02±022 C). The lake's temperature supports aquatic life, but challenges like low transparency (1.22±0.13 m), acidic pH levels (5.83±0.09), elevated ammonium levels (0.63±0.03 mg/l), low nitrate-nitrogen levels (0.0±50.00 mg/l), and fluctuating dissolved oxygen (6.50±0.29 mg/l) levels suggests pollution from agricultural runoff or sewage. The findings proffer effective management through pollution control, enhanced buffering capacity, and rigorous monitoring to safeguard biodiversity and ensure longterm ecological health.

Chemical and Physical Characterization of Three Oxidic Lithological Materials for Water Treatment

Water treatment necessitates the sustainable use of natural resources. This paper focuses on the characterization of three oxidic lithological materials (OLMs) with the aim of utilizing them to prepare calcined adsorbent substrates for ionic adsorption. The three materials have pH levels of 7.66, 4.63, and 6.57, respectively, and organic matter contents less than 0.5%. All of the materials are sandy loam or loamy sand. Their electric conductivities (0.18, 0.07, and 0.23 dS/m) show low levels of salinity and solubility. Their CEC (13.40, 13.77, and 6.76 cmol(+)kg) values are low, similar to those of amphoteric oxides and kaolin clays. Their aluminum contents range from 7% up to 12%, their iron contents range from 3% up to 7%, their titanium contents range from 0.3% to 0.63%, and their manganese contents range from 0.007% up to 0.033%. The amphoteric oxides of these metals are responsible for their ionic adsorption reactions due to their variable charge surfaces. Their zirconium concentrations range from 100 to 600 mg/g, giving these materials the refractory properties necessary for the preparation of calcined adsorbent substrates. Our XRD analysis shows they share a common mineralogical composition, with quartz as the principal component, as well as albite, which leads to their thermal properties and mechanical resistance against abrasion. The TDA and IR spectra show the presence of kaolinite, which is lost during thermal treatments. The results show that the OLMs might have potential as raw materials to prepare calcined adsorbent substrates for further applications and as granular media in the sustainable treatment of both natural water and wastewater.

Assessment of the Heavy Metal Contaminations of Roadside Soil in Aizawl, Mizoram (India): An In-Depth Analysis Utilising Advanced Scientific Methodologies

The study was conducted to evaluate the heavy metal contamination levels in the roadside soil of Aizawl, Mizoram (India). Twelve sites were sampled monthly from August 2020 to July 2021, and concentrations of copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) were analyzed using atomic absorption spectrometer. The concentrations of heavy metals at the twelve studied sites varied widely from 0.43-1.06, 20.54-21.21, 2.69-3.41, 0.25-0.54, 0.31-0.49 and 1.35-1.77 for Cu, Fe, Mn, Ni, Pb, and Zn respectively. Pollution assessment tools such as the pollution load index, geo-accumulation index, and enrichment factor indicated moderate pollution levels. The study also observed fluctuations in the contamination levels due to the monsoon rainfall and the COVID-19 pandemic lockdown. Principal component analysis identified vehicular emissions, industrial activities, and atmospheric deposition as the potential sources of heavy metal contamination, with varying patterns observed at each site. While the observed heavy metal concentrations generally met permissible limits, the elevated levels suggested anthropogenic influences. It is crucial to continuously monitor and manage heavy metal contamination to mitigate potential health risks associated with heavy metal exposure.

Hydrogeochemical analysis of processes affecting HCH removal using ZVI-based treatment technology

In the 1960s, ca. 3000–5000 tons of HCH residue were disposed of in an overburden dump at the Hájek kaolin/uranium mine site (Czech Republic). The dump leachate, which has a 136 μg/l average total content of hexachlorocyclohexane (HCH) isomers, discharges into a local creek and contaminates the ecosystem. A full-scale prototype for the treatment of dump leachate comprised three sequential stages: 1) permeable reactive modules filled with macro-zerovalent iron (mZVI), 2) a biosorption module and 3) an aerobic wetland module. After commissioning, HCH removal efficiency reached 95%, but decreased to 70% over the following 230 days, primarily due to the efficiency of the mZVI modules dropping from 76% to 39%. Hydrogeochemical analysis and geochemical modelling revealed that the reduction in efficiency was mainly caused by passivation of mZVI surfaces and clogging of mZVI pore spaces through precipitation of goethite, calcite and rhodochrosite, or siderite and magnetite instead of goethite where boundary conditions for O2 differed. XRD analysis of the solid phase from the mZVI modules confirmed the geochemical modelling results. The major part of the precipitated products (46–66 wt%) comprised a ferric hydroxide amorphous phase, especially in the initial mZVI module inlet, with goethite the second most abundant precipitate (10–40 wt%). Siderite and calcite also mainly precipitated in the initial module inlet. In conclusion, mZVI appears to be a suitable reductant for HCH; however, the longevity of the ZVI-based treatment system was negatively affected by precipitates in the presence of high concentrations of iron, manganese and carbonate species.

Biofortification in garden peas through multi-micronutrient formulations

Soil micronutrient deficiencies lead to crops with low essential element concentrations, affecting human health through micronutrient malnutrition. Effective practices, like foliar nutrient application, improve crop quality and reduce malnutrition. The garden pea (Pisum sativum L. var. hortense) is cultivated worldwide for its nutritional value and such nutrient-rich crops, through agronomic biofortification, offer a sustainable solution to global health issues by addressing micronutrient deficiencies. Four liquid micronutrient formulations [Treatment 1 (T1), Treatment 2 (T2), Treatment 3 (T3), and Treatment 4 (T4)] were prepared using either water or vermiwash as a carrier, with variations that included the presence or absence of plant growth regulators (GA3 + NAA)] and evaluated along with commercially available formulations [Arka Vegetable Special (T5) and ProKissan (T6)]. Micronutrient formulations, particularly T3, demonstrated notable effects on various parameters, including plant height, biomass, root characteristics, pod weight, and micronutrient contents in seeds of garden pea var. Kashi Nandini. T3 significantly outperformed other formulations in promoting plant growth, resulting in higher values for plant height, biomass, branches per plant, nodule mass, root biomass, surface area, volume, and density. Yield parameters such as pod length, weight, number of pods, and seeds per pod were also positively influenced by micronutrient treatments, with T3 leading to the highest overall yield, with a 24.09 % increase per plant and a 13.39 % increase per hectare compared to the control. Additionally, foliar application of micronutrients increased the concentration of copper, zinc, iron, and manganese in seeds, positively impacting seed quality. Quality parameters, including total soluble solids, protein, total phenol, and total flavonoid contents, were significantly improved by micronutrient treatments, with T3 showing the most favorable outcomes. Texture analysis indicated that peas treated with T3 had lower firmness values, suggesting maintained tenderness and sweetness. Correlation analysis revealed strong positive associations between various growth parameters, yield traits, and micronutrient contents. Overall, foliar micronutrient application proved to be a valuable biofortification strategy for enhancing the performance and quality of garden peas.

Bacterial association with metals enables in vivo monitoring of urogenital microbiota using magnetic resonance imaging

Bacteria constitute a significant part of the biomass of the human microbiota, but their interactions are complex and difficult to replicate outside the host. Exploiting the superior resolution of magnetic resonance imaging (MRI) to examine signal parameters of selected human isolates may allow tracking of their dispersion throughout the body. Here we investigate longitudinal and transverse MRI relaxation rates and found significant differences between several bacterial strains. Common commensal strains of lactobacilli display notably high MRI relaxation rates, partially explained by elevated cellular manganese content, while other species contain more iron than manganese. Lactobacillus crispatus show particularly high values, 4-fold greater than any other species; up to 60-fold greater signal than relevant tissue background; and a linear relationship between relaxation rate and fraction of live cells. Different bacterial strains have detectable, repeatable MRI relaxation rates that in the future may enable monitoring of their persistence in the human body for enhanced molecular imaging.

Sources Analysis and Health Risk Assessment of Heavy Metals in Street Dust from Urban Core of Zhengzhou, China

Fifty-one street dust samples were systematically collected from the urban core of Zhengzhou, China, and analyzed for potentially toxic metals. The concentrations of vanadium (V), manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), lead (Pb), and nickel (Ni) in the samples surpassed the background values of the local soil, indicating a notable potential for contamination. Spatially, the traffic area was the most polluted with a total heavy metal concentration of Cu, Zn, As, Pb, and Ni, while the pollution levels were lower in the culture and education area and commercial area with total concentrations of V and Mn. Seasonal variations were discerned in the concentrations of heavy metals, with V, Cu, Zn, and As exhibiting heightened levels during the fall and winter, while Mn, Ni, and Pb reached peaks in the spring season. Zn exhibited the highest mean geo-accumulation index (Igeo) value at 2.247, followed by Cu at 2.019, Pb at 0.961, As at 0.590, Ni at 0.126, Mn at −0.178, and V at −0.359. The potential ecological risk index (RI) in the traffic-intensive area markedly exceeded other functional areas. Health risk assessments showed that children were more vulnerable to heavy metal exposure than adults, particularly through the ingestion pathway. Correlation analysis, principal component analysis (PCA), and cluster analysis (CA) were applied in conjunction with the spatial–temporal concentration patterns across various functional areas to ascertain the plausible sources of heavy metal pollutants. The results indicated that heavy metals in the urban street dust of Zhengzhou were multifaceted, stemming from natural processes and diverse anthropogenic activities such as coal burning, industrial emissions, traffic, and construction operations.