Atomic Absorption Spectrometry Research Articles

Assessment of heavy metals contamination/pollution of phosphogypsum waste of the Mdhilla region (Gafsa, southern Tunisia).

Tunisia is currently faced with the extremely delicate problem of managing the millions of tons of phosphogypsum (PG) discharges which is already causing considerable environmental damage. The research carried out in this work is part of a geochemical assessment of the level of heavy metal contamination in phosphogypsum waste from the Mdhilla region (Gafsa, southern Tunisia). The assessment of ETM contamination/pollution is based on the relatively simple principles of measuring concentrations, calculating indices, and comparing them with established standards, which vary according to the nature of the element, its toxicity, and the receiving environment. Six PG samples are taken from the storage heaps right next to the chemical group's plant. Our investigations to assess the level of heavy metals contamination focused on: zinc (Zn), chromium (Cr), copper (Cu), nickel (Ni), and cadmium (Cd). These metallic elements are measured by atomic absorption spectrometry. To achieve our objectives, we calculated several indices, such as the geo-accumulation index (Igeo), the contamination factor (FC), the degree of contamination (DC), and the sediment pollution index (IPS). The index approach enables us to predict the extent of heavy metal pollution in these PG discharges from the Mdhilla region. The Mdhilla region's PG heavy metals contents show the following order of abundance: Zn > Ni > Cr > Cd > Cu. Calculation of contamination/pollution indices reveals in principle polymetallic contamination dominated by three elements: cadmium, nickel, and copper.

The Bioaccumulation of Potentially Toxic Elements in the Organs of Phragmites australis and Their Application as Indicators of Pollution (Bug River, Poland)

The bioaccumulation of potentially toxic elements (PTEs) in aquatic plants is critical in assessing the quality of aquatic environments and the risks associated with anthropogenic activities. This research involved using Phragmites australis as a bioindicator in a comprehensive assessment of the spatial variation in pollution within the Bug River catchment, employing advanced statistical methods to identify pollution sources. The study aimed to investigate the bioaccumulation of PTEs in different parts of the P. australis plant and to evaluate their suitability as bioindicators of contamination. Plant samples were collected from 32 locations in the Bug River catchment, and the concentrations of metals such as Cd, Pb, Cr, Ni, Zn, Cu, Fe, and Mn were determined by atomic absorption spectrometry. The results indicated that PTE accumulation was highest in the roots, underscoring their crucial role in monitoring metal concentrations. Metal concentrations differed based on land use within the catchment area, with the highest levels observed in urbanized regions, highlighting the significant impact of human activities like wastewater discharge and transport emissions. The highest concentrations were observed for Fe, Mn, and Zn, while Cd concentrations were notably elevated in agricultural areas. The analyses confirmed that P. australis serves as an effective bioindicator of heavy metal contamination and can be employed in long-term biomonitoring programs.

Association of whole blood essential metals with neurodevelopment among preschool children.

Essential metals may play roles in neurodevelopment. The aim was to evaluate the associations of magnesium (Mg), iron (Fe), copper (Cu), and zinc (Zn) levels with neurodevelopment among preschool children. The medical records of eligible children enrolled between January 2019 and July 2022 were retrospectively reviewed for required information. The quantitative measurement of metals was conducted using atomic absorption spectroscopy, while screening of neurodevelopment was performed using the Ages and Stages Questionnaire. Modified Poisson regression and Bayesian kernel machine regression (BKMR) analyses were used to evaluate the prevalence ratio (PR) of their independent and joint associations. 662 (14.8%) children were found to have possible neurodevelopmental delays. Modified Poisson regression showed that Mg, Cu, and Zn levels were independently and negatively associated with the risk of neurodevelopmental delay. The PRs (95% CIs) for per log2 increment of the above metals were 0.35 (0.19-0.62), 0.57 (0.42-0.77), and 0.63 (0.42-0.96). These negative associations were more pronounced in the gross motor and personal-social domains while considering the concrete five domains. BKMR showed a negative association of metal mixture with the risk of neurodevelopmental delay. Mg, Cu, and Zn were inversely associated with neurodevelopmental delay. Sufficient essential metal levels are important for neurodevelopment. Essential metals play a key role in neurodevelopment. The association of essential metal mixture with neurodevelopment is relatively scarce. Preschool children with possible neurodevelopmental delay are found to have lower Mg, Cu, and Zn levels than their counterparts. Single Mg, Cu, Zn levels, and elevated essential metal mixture are negatively associated with the risk of possible neurodevelopmental delay.

Phytochemical screening, nutritional, antinutritional, antioxidant, GCMS and mineral analysis of Zanthoxylum rhetsa (Roxb.) DC: Insights from tribal consumption in Mizoram, Northeast India

The plant Zanthoxylum rhetsa Roxb, a member of the Rutaceae family, holds dual significance in certain communities, particularly in Mizoram, Northeast India, where it is valued for its medicinal properties and consumed as a vegetable. This study comprehensively analyzes the phytochemical, nutritional, antinutritional, and antioxidant properties and the mineral content of Z. rhetsa, a plant traditionally consumed by tribal communities in this region. Minerals such as aluminum, copper, iron, manganese, nickel, and zinc were measured using Atomic Absorption Spectroscopy (AAS). Gas Chromatography-Mass Spectrometry (GC-MS) analysis was conducted to determine the chemical composition of the samples. Phytochemical screening revealed the existence of several bioactive components, such as tannins and flavonoids, while nutritional studies validated the plant's abundance of key nutrients. Among the minerals, manganese was found in the highest concentration (481.356 mg/100 g of DW), while nickel was present in the lowest concentration (1.614 mg/100 g of DW). The total calorific content was ascertained to be 51.344 Kcal/100g, adequate for dietary requirements. Additionally, the total phenolic content measured was 8.28 mg/g in gallic acid equivalent, and the total flavonoid content was 43.04 mg/g in quercetin equivalents. The existence of antinutritional compounds in differing amounts necessitates meticulous evaluation, particularly with the intake of fruits that may possess elevated levels of these substances. This comprehensive assessment highlights the nutritional significance of Z. rhetsa in local diets, emphasizing its dual role as a source of beneficial nutrients and potential antinutritional factors.

Ecological and Health Risks from Trace Elements Contamination in Soils at the Rutile Bearing Area of Akonolinga, Cameroon

This study evaluates the concentrations of trace elements (TEs) in soils from the rutile deposit area of Akonolinga, Cameroon, and analyzes the associated health risks. A total of 25 samples were analyzed using flame atomic absorption spectrometry (FAAS). The results show that TE concentrations follow the decreasing order Fe, Ti, Zr, Mn, Cr, V, Ba, Zn, Nb, Ni, Pb, Ga, Cu, Co, Y, Br, and Sn. Pollution indices and the Pearson correlation matrix reveal moderate correlations between Fe and several other TEs, indicating a common origin. Enrichment Factors show significant enrichment in Zr, Nb, and Ti, with notable enrichment in Cr and Co at certain sites. Although the Geo-Accumulation Index indicates no direct contamination and the overall ecological risk is low, the Contamination Factor reveals high levels for Cr, Nb, Ti, and Zr. The carcinogenic risk is moderate, while non-carcinogenic risks are high for children and considerable for adults. These research highlight the potential public health impacts in this mining region and provide essential baseline data for future environmental risk management.

Determination of Metal Cadmium (Cd), Copper (Cu), Iron (Fe) and Zinc (Zn) in Drinking Water from The Boring Well of Surbakti Village, Karo District by Atomic Absorption Spectrophotometry Method

Water is an essential requirement for human existence. In addition to traditional water usage, water is essential for enhancing the quality of human existence and facilitating industrial and technological endeavors. An investigation was conducted on the contents of Cadmium (Cd), Copper (Cu), Iron (Fe), and Zinc (Zn) in drinking water from drilled wells in Surbakti Village, Karo District, employing Atomic Absorption Spectrophotometry (AAS) techniques. Sampling occurred during weeks 1, 2, 3, 4, and 5 and was subsequently digested with concentrated nitric acid until a volume of 15 mL was attained. The metal concentrations of Cd, Cu, Fe, and Zn were quantified using Atomic Absorption Spectroscopy (AAS) using a calibration curve. The findings indicated a concentration of Cd at 0.0031 mg/L, Cu at 0.0470 mg/L, Fe at 0.2741 mg/L, and Zn at 0.2929 mg/L. In this instance, Cd produced a greater concentration of drinking water standards compared to Cu, Fe, and Zn. Nonetheless, it nonetheless met the drinking quality standards established by Regulation Minister of Health No. 492/Menkes/Per/VII/2010.

Algal Biosensors for Detection of Potentially Toxic Pollutants and Validation by Advanced Methods: A Brief Review

The presence of potentially toxic pollutants, such as pesticides and metal ions, even at low concentrations, can significantly impact aquatic environmental health. This pollution is a globally widespread problem and requires fast and reliable analysis, especially for in-situ identification/quantification. Atomic absorption spectrometry and plasma-based spectrometry techniques have been considered the most analytical tools used to monitor potentially toxic metal ions in aquatic media and other related matrices. The dynamics of global climate change and its correlation with pollution, especially from anthropogenic sources, have encouraged the development of other faster analytical tools for monitoring these pollutants. A noteworthy alternative for determining potentially toxic pollutants is using algae-based biosensors, resulting in a cost reduction and simplification of environmental analysis, enabling a more reliable comprehension of the role of humans in climate change. These biosensors, which may not have the highest sensitivity in quantification, have demonstrated remarkable potential in the identification of potentially toxic pollutants and several field applications. Biosensors can be an excellent biotechnology solution for monitoring global environmental changes. Thus, this review highlights the main advances in developing and comparing algae-based biosensors and other analytical possibilities for the identification of potentially toxic pollutants and their possible applications in environmental analysis.

Assessment of human health risks posed by toxic heavy metals in Tilapia fish (Oreochromis mossambicus) from the Cauvery River, India

Heavy metal toxicity is a serious threat to human health due to its bioaccumulation, biomagnification, and persistent nature in the environment including aquatic systems. In the recent past, heavy metal contamination in the environment has occurred due to various anthropogenic sources. The concentration of potentially toxic heavy metals was determined by Atomic Absorption Spectroscopy in Tilapia (Oreochromis mossambicus), a highly farmed and consumed fish species in southern parts of India. The mean levels of Fe were found to be higher in major organs of the fish with the highest levels in liver (Mean 1554.4 ± 1708.7 mg/kg) and lowest in the muscles (Mean 130.757 ± 33.3 mg/kg). Correlation Matrix analysis revealed relationships between the occurrence of various heavy metals in different organs of fish and indicated similar origins and chemical properties. Target hazard quotient for Cd, Co, Pb, and Cr in the Liver, Co and Cr in the Gills, and Co in Muscle were > 1 for adults, which showed a significant health risk from the combined effects of these metals. The potential health risk to humans, according to the cancer risk (CR) assessment is attributed mainly to Cd and Cr levels. Overall, moderate fish consumption is advised to limit the bioaccumulation of heavy metals over prolonged exposure and associated health risks.

Saturated absorption spectroscopy of 87Rb atoms using structured light: Observation of narrow hyperfine and crossover resonances

Abstract An experiment on the saturated absorption spectroscopy (SAS) of 87Rb-D2 line is performed using the Laguerre-Gaussian (LG) beam as structured light. The theoretical simulation of which is done by considering a four-level atom-laser coupled system. The theoretically simulated spectra fairly match with the experimentally observed spectra. The line-width narrowing behavior of both the observed hyperfine and crossover resonances in the Doppler-broadened probe absorption spectra is attributed by the spatially dependent Rabi frequency of the pump LG beam irrespective of the characteristics of the probe beam. The results also illustrated that the narrowing behavior of the line shapes of the hyperfine structure using the LG beam is universal in nature, i.e. irrespective of hyperfine or crossover transitions. This structured light-induced narrowing of line-width of the sub Doppler hyperfine and crossover resonances can be utilized for high-precision laser frequency locking at a particular hyperfine or crossover transition. Moreover, a significant narrowing of hyperfine and crossover resonances with the variation of the orbital angular momentum (OAM) number of the LG beam shows that the generated SAS signal can be manipulated by using the OAM of the structured light as a control knob.

Conversion Single Reagent of n-Propanol to 1,1-Dipropoxypropane Using Cr/Activated Carbon Catalyst

Synthesis of 1,1–dipropoxypropane from a single reagent of n-propanol using Cr/Activated Carbon (Cr/AC) as a catalyst has been done. Activated carbon (AC) was prepared by activating coconut shell carbon at 650 °C in the atmosphere of N2 at a flow rate of 20 mL/min for 4 h, and then it was washed using acetone in a Soxhlet for 15 rounds, washed three times by 1.0 M HCl, and finally, it was sieved at 60–80 mesh. Metal content was analyzed using atomic absorption spectroscopy (AAS) and represented by Na, Ca, and Fe. The AC was impregnated with Cr (VI) solution and reduced with H2 at 650 °C. The acidity of the Cr catalyst was determined by the adsorption of ammonia. Optimation of n-propanol conversion to 1,1-dipropoxypropane using Cr/AC catalyst in the atmosphere of N2 was conducted in an oven using variations of temperature of 450, 500, and 550 °C, amount of catalyst of 5, 10, and 15 g, and flow rate of alcohol of 0.10, 0.50, and 0.90 mL/min. The conversions of 1,1-dipropoxypropane were analyzed by GC-MS and 1H-NMR. The results showed that the AC's metal content significantly decreased after washing with acetone and 1.0 M HCl. The AC and Cr/AC had 2.49 and 8.27 mmol/g acidity, respectively. The highest product of 1,1-dipropoxypropane of 65.0% was reached at 450 °C using a 5 g catalyst at a flow rate of the alcohol 0.10 mL/min.

Phytoremediation of Mercury and Cyanide Contaminated Soils by Physic Nut (Jatropha curcas L.) and Citronella Grass (Cymbopogon nardus)

Mercury and cyanide are compounds that have the potential to pollute the environment, both of which are found in the tailing waste of artisanal and small-scale gold mining (ASGM). The purpose of this study was to determine the ability of physic nut (Jatropha curcas L.) and citronella grass (Cymbopogon nardus) to absorb mercury and cyanide in soils polluted with tailings waste based on the value of transfer factors. During this research stage, the remediation of soil polluted with amalgamation tailings and cyanide tailings was carried out for 28 days. Soil sampling was carried out every seven days for 28 days, while root and leaf sampling was carried out on day 28, analysis of mercury and cyanide content in soil and plants using atomic absorption spectroscopy (AAS) and UV-visible spectrophotometer. After 28 days of remediation, mercury and cyanide levels may decrease in soil by 93.7% for mercury and 81.8% for cyanide. The decrease can be caused by absorption and accumulation in plants, where mercury and cyanide accumulate more in physic nut than citronella grass. Physic nut and citronella grass have a transfer factor value of <1 for mercury and cyanide, so they are an excluder plant, except for the accumulation of mercury in physic nut from cyanide tailings soil, which has a transfer factor value of >1, which is an accumulator plant.

Impact of acute PM2.5 exposure on pediatric blood lead levels: evidence from Beijing, China

Research on the effects of fine particulate matter (PM2.5) on blood lead levels (BLL), particularly in children, remains limited. This study aimed to investigate the relationship between acute ambient PM2.5 exposure and BLL in children aged below 14. A total of 23,732 children were included in the study, with BLL measured using atomic absorption spectrometry. Generalized additive models (GAM) were employed to analyze the connection between children’s BLL and acute PM2.5 exposure. From April 2008 to June 2017, Beijing’s average PM2.5 concentration was 91.71 ± 74.55 μg/m³, approximately 2.62 times higher than the annual average concentration recommended by the WHO Ambient Air Quality Standard (35 μg/m³). The mean (±SD) BLL of children was 0.2105 ± 0.0963 μmol/L, with a median of 0.20 μmol/L. The data indicated an increase in BLL with age and a significant difference in BLL between boys and girls (p < 0.05). The analysis revealed a non-linear relationship between BLL and PM2.5 exposure after adjusting for variables such as gender, age, blood levels of Cu, Fe, Ca, Mg, Zn, analysis batch, and heating season. PM2.5 exposure significantly impacted children’s BLL.

Study on the Thermal Control Performance of Mg-Li Alloy Micro-Arc Oxidation Coating in High-Temperature Environments

This paper reports on the successful preparation of a low absorption–emission thermal control coating on the surface of LAZ933 magnesium–lithium alloy using the micro-arc oxidation method. This study analyzed the microstructure, phase composition, and thermal control properties of the coating using Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), UV–visible near-infrared spectroscopy (UV-VIS-NIR) and infrared emissivity measurements. The results indicate that the hemispherical emissivity of the coating remains unaffected with an increase in temperature and holding time, while the solar absorption ratio gradually increases. The thermal control performance of the coating after a high-temperature experiment was found to be related to the diffusion of the Li metal element in the magnesium lithium alloy matrix, as determined by X-ray photoelectron spectroscopy (XPS), flame graphite furnace atomic absorption spectrometry (GFAAS) and Glow Discharge Optical Emission Spectroscopy (GD-OES). As the holding time is extended, the coating structure gradually loosens under thermal stress. The Li metal element in the substrate diffuses outward and reacts with O2, H2O and CO2 in the air, forming LiO2, LiOH, Li2CO3 and other products. This reaction affects the coating’s solar absorption ratio in the end.

Activated Charcoal-Alginate Platform for Simultaneous Local Delivery of Bioactive Agents: At the Nexus of Antimicrobial and Cytotoxic Activity of Zn2+ Ions

Antimicrobial resistance (AMR) is a global public health threat that affects cancer patients more than the general population. In this work, a composite system based on Zn-alginate hydrogel and activated charcoal (AC) particles that, upon contact with physiological fluids, simultaneously releases bioactive agents (Zn2+ and AC particles impregnated with povidone–iodine) was designed to locally address specific problems characteristic for malignant wounds (MWs). This composite was comprehensively investigated in vitro regarding its morphology (field-emission scanning electron microscopy), Zn2+ release (flame atomic absorption spectrometry), iodine adsorption and desorption from AC particles (energy dispersive X-ray analysis and UV–visible spectroscopy) as well as its antimicrobial and antitumor activity. With respect to the ongoing AMR crises, antimicrobial activity was tested against a wide range of wild multi-drug resistant bacterial and yeast strains, all isolated from patient wounds. Since Zn2+ ions proved to be selectors of resistant strains of bacteria, the synergistic activity of AC particles and adsorbed iodine was shown to be crucial for excellent antibacterial activity. On the other hand, the synergy of AC particles and Zn2+ ions showed an equally strong antifungal effect. In addition, antimicrobial concentrations of Zn2+ ions showed cytotoxic activity against two cancer cell lines derived from cancers affecting skin either as metastatic cancer (breast cancer MDA-MB-453 cell line) or primary cancer of the skin (malignant melanoma Fem-X cell line), which enables Zn2+ ions to be further investigated as potent local agents targeting malignant cells.

The effect of water filter pitchers on the mineral concentration of tap water.

To investigate the effect of water filter pitchers on the concentration of different minerals in tap water. Nine water filter pitchers (A-I) were chosen based on consumer preferences and Amazon reviews. Each filter was tested for its ability to modify the concentrations of fluoride, calcium, magnesium, potassium, and sodium in tap water. Tap water samples were collected before and after filtration, at various intervals (1, 5, 10, 30, 50, 75, and 100 L) during filtration, and analyzed using an ion-specific electrode (fluoride) and atomic absorption spectrometry (other minerals). Statistical analyses were conducted to compare filtered and unfiltered water mineral concentrations. Water filter pitcher effect: Filters F (p < 0.001) and G (p = 0.030) decreased fluoride concentrations. All filters except I (p = 0.235) and H (p = 0.717) decreased calcium concentrations (p < 0.01). Filters E (p = 0.018), D (p = 0.014), and G (p = 0.010) decreased magnesium concentrations. Filters I (p = 0.028) and D (p = 0.009) increased potassium concentrations. Filter A (p = 0.002) increased sodium concentrations, while C (p = 0.034) decreased sodium concentrations. Effect of filter aging: All filters affected mineral concentrations over time but to varying extents. Filter G had the most pronounced effect on reducing mineral concentrations compared to all others. No filter was able to completely remove fluoride from tap water, contrary to the claims made by three manufacturers. The present study highlighted that water filter pitchers vary greatly in their ability to affect mineral concentrations in tap water during their use. Further research is needed to develop more effective water treatment solutions.

Evaluation of Cadmium, Lead, Chromium, and Nickel Content in Various Types of Nuts: Almonds, Cashews, Hazelnuts, Peanuts, and Walnuts - Health Risk of Polish Consumers.

World production and consumption of nuts continue to rise year on year. Nuts, due to their high nutrient content, are becoming increasingly popular among consumers. A potential health risk may result from the consumption of nuts contaminated with metallic trace elements like cadmium or lead. In this research, we measured the content of Cd, Pb, Cr, and Ni in various edible nuts. All elements were detected using the electrothermal atomic absorption spectrometry analytical technique (ETAAS). The study material comprised 69 nut samples including almonds, cashews, hazelnuts, peanuts, and walnuts available on the Polish market. Indicators such as the hazard quotient (HQ) and hazard index (HI) were used to assess the health risk of consumers. The concentrations of elements in all analyzed samples of nuts were as follows: Cd: peanuts > almonds > hazelnuts > walnuts > cashews, Pb: peanuts > almonds > hazelnuts > walnuts > cashews, Ni: cashews > peanuts > walnuts > hazelnuts > almonds, Cr: almonds > cashews & hazelnuts > peanuts > walnuts. Health risk indicators estimated for consumers whose diet is rich in nuts, in which metallic trace elements were recorded, indicate that an unacceptable impact may occur, and the risk of negative health effects (non-cancer) will be moderate to high.

Use of lignocellulose-degrading enzyme bio-cemented soils in the construction industry

In their activity, termites break down biomass into glucose, forming cementitious compounds. This results in rainfall-resistant mounds for their shelters, which interests the construction industry. This study explored the potential application of the abundant naturally bio-cemented termite mound soils in highway construction. Experimental investigations compared these mound soils to surrounding soils, revealing that mound soils are 68.2% finer in particle size distribution and have 81.4% lower organic content. Atterberg limits indicated 14.6% higher plasticity and a 5.3% increase in specific gravity for mound soils. Atomic Absorption Spectroscopy (AAS) showed no significant difference in chemical composition. Proctor tests indicated that the compaction characteristics of the soils were comparable, confirming their engineering viability without modifications. Mound soils exhibited a twofold increase in Unconfined Compressive Strength (UCS) and a 33.9% increment in California Bearing Ratio (CBR) strength. One-way ANOVA tests confirmed these differences with p-value ranges of 0.0056-0.0361 below the 0.05 significance threshold. The study advocates utilising eco-friendly naturally bio-cemented mound soils in highway construction, meeting minimum standards. Mound soils from one acre can construct up to 2,500m highway, optimising resource use, promoting sustainability by repurposing natural materials, and significantly reducing carbon emissions. Further research on soil improvement using lignocellulose-degrading enzymes is recommended.

A Comparative Study of the Physio-Mechanical Properties of Iron Fillings and Mild Steel Chips in Reinforced Particleboard

This study compared the physio-mechanical characteristics of mild steel chips and iron fillings on sawdust-produced particleboard to regular particleboard made from sawdust alone, using identical production conditions. Particle board was made using 1.18mm sawdust, 3mm mild steel chips, and iron filler with diameters of 0.15mm, 0.425mm, 0.6mm, 1.18mm, and 2.0mm. 70g of sawdust, 40g of iron fillings, and 40g of mild steel chips were used in the production process. 50ml urea formaldehyde was used as a binder. The atomic absorption spectroscopy was determined for iron fillings and mild steel chips. Particleboards were produced at a temperature of 160°C and a pressure of 20 tons for 15 minutes. Mechanical property tested indicates that particleboard containing iron filings has a lower Modulus of rupture (MOR) because the size of the iron filings in the particleboard reduces as the MOR increases. The particle size of iron filling with the value of 2.0mm had the least MOR of 3.99mpa/m2 in iron filling samples. The MOR of Mild steel chips was higher compared to all the samples analyzed. Modulus of Elasticity (MOE) of particleboard produced from iron filings increases as the particle sizes of iron filings increases. The samples containing iron filings alone showed the highest MOE of 244.89 MPa/m2 for 2.0 mm particle board, while the ones containing mild steel chips had the highest MOE of 282.82 MPa/m2 across all samples, suggesting their strength as reinforcement. The rate of water absorption and thickness of swell of particleboard produced from iron filings increases as the size of the iron fillings increase.

Assessment of the Environmental Impact of Fly Ash on the Concentration of Heavy Metals around Cement Company of Northern Nigeria

This study assessed the impact of Coal Fly Ash on the concentration of Heavy metals in water, soil, and vegetables (moringa and spinach) in the environment of Cement Company of Northern Nigeria. The samples collected were digested, and analysed for heavy metals concentration using Atomic Absorption Spectroscopy. The concentrations of heavy metals obtained in water samples were higher than the WHO/SON permissible limit, except for Cu and Zn which are below the standard limits. The average concentration of Pb, Mn, Cd, and Ni in all plant samples was higher than the permissible limit, except Cd in spinach sample. The roots of the spinach accumulate higher concentrations of heavy metals than the leaves and stem, while leaves of moringa accumulate higher than the roots and stem. The concentration of heavy metals in soil sample was below the WHO limit. Comparatively the plants samples have the highest concentrations of heavy metals than the water and soil samples. The coal fly ash from the Cement Company must have contributed to the significant concentration of Heavy metals in the environment making the water and plants from the study area unfit for human and animal consumption.

The Utilization of Vegetable Powders for Bread Enrichment—The Effect on the Content of Selected Minerals, Total Phenolic and Flavonoid Content, and the Coverage of Daily Requirements in the Human Diet

The aim of this study was to evaluate the content of selected minerals and total phenolic and flavonoid content of wheat bread and bread enriched with varying amounts of carrot powder (CP) and pumpkin powder (PP). In addition, the coverage of daily requirements of selected minerals was evaluated after the consumption of 100 g of each type of bread. The research included seven types of bread: wheat bread (WB) and bread enriched with 10%, 20%, and 30% CP and PP. The vegetable powders were obtained by freeze-drying. The concentrations of minerals—sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn)—were determined by atomic absorption spectroscopy (AAS) method. Coverage of daily requirements after consumption of a serving of bread was determined based on Recommended Daily Allowance (RDA) and Adequate Intake (AI) ratios for minerals, according to the nutritional standards for the Polish population. The addition of 10% PP led to a greater increase in Na, K, Mg, and Cu in the bread compared to CP, while for Ca, Fe, Zn, and Mn a greater increase was observed with the addition of 10% CP than PP. Among macronutrients, the greatest changes in content were recorded for Ca—the addition of 10 and 20% CP and PP resulted in increases of 66, 113, 51 and 59%. Among micronutrients, the addition of CP and PP to wheat bread caused the largest changes in Cu (46–150% increase) and Mn (25–99% increase) content. Additionally, there was a tenfold increase in total phenolic content (TPC) when 30% CP was added to the bread. Consuming 100 g of bread with CP and PP provided the greatest coverage of K (41–60%), Cu (8–17.5%), and Mn (6–17%). These findings suggest that fortification of bread with vegetable powders has the potential to be a useful method of enriching the mineral composition and increasing the proportion of selected minerals in the human diet.