Analysis Of Heavy Metals Research Articles

Screening and Stress Responsive Characteristics of Potential Hyperaccumulator of Pb, Zn, and Cd Compound Heavy Metals

To screen for Pb, Zn, and Cd composite heavy metal hyperaccumulator plants, a survey, sampling, and analysis of dominant plants in typical lead-zinc mines and smelter areas in Baoji City were conducted. Potential Pb, Zn, and Cd composite heavy metal hyperaccumulator plants were initially screened, and a pot experiment of soil cultivation was carried out to observe the response characteristics of chlorophyll （chlorophyll a, chlorophyll b, carotenoids, and total chlorophyll）, antioxidant enzymes （SOD, CAT, and POD）, and other physiological indicators （MDA and proline） under the stress of Pb, Zn, and Cd composite heavy metals. A field experiment was also conducted to further verify and determine their enrichment ability for Pb, Zn, and Cd composite heavy metals, aiming to provide scientific basis and technical support for the remediation of Pb, Zn, and Cd composite heavy metal-polluted soil. The field survey revealed that Symphytum officinale L. met the international hyperaccumulator plant index requirements for the enrichment of Pb, Zn, and Cd, with enrichment quantity, bioconcentration factor （BCF）, and transfer factor （TF） all meeting the requirements. It was a potential hyperaccumulator plant for Pb, Zn, and Cd composite heavy metals. The soil cultivation pot experiment showed that as the gradient of Pb, Zn, and Cd composite heavy metal stress increased, the content of chlorophyll a, chlorophyll b, and total chlorophyll in S. officinale L. leaves gradually decreased, causing disruption to the plant's photosynthetic system when the gradient was greater than or equal to IV. The chlorophyll content in Ricinus communis L. leaves exhibited a "low-stimulation-high-inhibition" phenomenon, while excessive stress stimulated the activation of its own protective systems, leading to reduced toxicity. In addition, there were significant differences （P < 0.05） in the content of chlorophyll a, chlorophyll b, carotenoids, and total chlorophyll between S. officinale L. and R. communis L. both compared to the control treatment and between stress gradients. The SOD activity in the leaves of S. officinale L. and R. communis L. showed a trend of increasing first, then decreasing, and then increasing. The CAT activity in the leaves of S. officinale L. exhibited a "low-stimulation-high-inhibition" effect, whereas the CAT activity in the leaves of R. communis L. showed a trend of continuous decrease. The POD activity in the leaves of S. officinale L. generally increased, whereas in the leaves of R. communis L., it increased first, then decreased, and then increased. The MDA content in the leaves of S. officinale L. generally decreased, whereas in the leaves of R. communis L., it exhibited an upward trend. In addition, whether compared to the control between stress gradients, there were significant differences （P < 0.05） in the SOD, CAT, POD, MDA, and proline content of S. officinale L. and R. communis L. The field experiment results indicated that S. officinale L. could meet the hyperaccumulator plant index requirements for the enrichment of Pb, Zn, and Cd, making it a potential germplasm resource for Pb, Zn, and Cd composite heavy metal hyperaccumulator plants. It can be an ideal choice for the remediation of Pb, Zn, and Cd composite heavy metal-polluted soil.

Structural alterations in scales of Capoeta capoeta (Güldenstädt, 1773) from heavy metal-contaminated river water.

Heavy metal pollution, especially in freshwater, is a serious problem for aquatic organisms and human health. In this study, the scales of Capoeta capoeta living in the Karasu River (Turkey), which is estimated to be contaminated with pollutants, especially heavy metals, were examined for structural anomalies. Two stations on the river were selected for this purpose. Fish and surface water samples were taken at the stations. The heavy metal analyses were carried out in the water and the fish tissue. Heavy metal pollution was detected in the surface water. It was also observed that some heavy metals (As, Cu, Cd, Cr, Mn, Pb, Ni, Zn) accumulate in the fish tissue. Significant structural differences were observed on the dorsal surface of the scales, such as interrupted primary radii, damaged circuli, damaged focus, damaged anterior scale margin, broken focus, deformed scale structure, scattered chromatophores, dilatation of primary radii, loss of focus, damaged annuli, symmetry shift in the lateral line canal, eroded circuli, damaged posterior scale margin, double focus, branching in the primary radii, asymmetric circuli, incomplete annuli and interrupted secondary radii in each of the fish collected from the contaminated site. Heavy metals are suspected to be responsible for the structural anomalies in the scales. Based on these observations, it can be said that fish scales can be used as an effective indicator of water quality.

A potential toxicological risk assessment of heavy metals and pesticides in irrigated rice cultivars near industrial areas of Dhaka, Bangladesh.

Rice intake represents a significant pathway through which humans accumulate heavy metals. This study presents a comprehensive analysis of heavy metal and pesticide contamination in rice cultivars irrigated with industrial wastewater near Dhaka, Bangladesh, a region heavily influenced by industrial activities. This study employed a unique methodology that not only quantified the concentrations of heavy metals and pesticide residues in rice grains but also extended to evaluating the physicochemical properties of rice stems, husks, soil, and irrigation water. The findings revealed alarmingly high levels of heavy metals such as lead, cadmium, chromium, nickel, and mercury in the soil and irrigation water, with concentrations in some cases exceeding the World Health Organization safety thresholds by 2 to 15 times. Notably, the rice grains also exhibited significant contamination, including substantial amounts of diazinon and fenitrothion pesticides, exceeding the established safety limits. The study employed hazard quotients (HQs) and cancer risk (CR) assessments to evaluate the potential health risks associated with the consumption of contaminated rice. The results indicated HQ values were greater than 1 for rice grains across the sampled fields, suggesting a considerable non-carcinogenic health risk, particularly from lead exposure, which was found at levels twice the standard limit in all the sampling fields. Moreover, the CR values for As, Pb, Cd, Co, and Mn highlighted a significant carcinogenic risk in several instances.

Preparation, Quality control and Standardization of a Destructive Distillate <i>Swasakasa Nei</i> (SKN), A Traditional Siddha Herbal Pharmaceutic for <i>Swasakasam</i> (Bronchial Asthma)

Standardization is essential to ensure the quality and reliability of traditional medicines. This study aimed to collect, authenticate and purification of raw materials, preparation of <i>Swasakasa Nei</i> (SKN) according to SOP, and Quality evaluation and Standardization procedures following Pharmacopoeial Laboratory of Indian Medicine (PLIM) guidelines. SKN, prepared as <i>Kuzhithylam</i>, is used to treat <i>Swasakasam</i> (Bronchial Asthma) in the Siddha system of medicine. The organoleptic characters of <i>Swasakasa Nei</i> reveal that SKN was a black, thick semisolid with a smoky odour, greasy consistency, and free-flowing nature drug. Physicochemical analysis showed values for Saponification Value (202.19), Iodine Value (30), Acid Value (7.25%), Peroxide Value (0.58%), Refractive Index (1.462), Specific Gravity (0.9131 g/ml), Loss on Drying (34.17%), Total Fatty Matter (60.18%), Free Fatty Acids (1.06%), and Unsaponifiable Matter (0.98%). The congealing point was 19°C, with no mineral oil and definite oxidation on rancidity. HPTLC fingerprint analysis revealed multiple prominent peaks at various wavelengths. Microbial contamination tests showed no specific microbes, and aflatoxin assays confirmed SKN was free from Aflatoxins B1, B2, G1, and G2. Pesticide residue analysis detected no organochlorine, organophosphorus, or pyrethroids, and heavy metal analysis showed no trace elements or heavy metals. These standards affirm the authenticity, genuineness, and safety of SKN, contributing to its scientific validation.

Bacillus subtilis as an effective tool for bioremediation of lead, copper and cadmium in water

Bioremediation is a promising technique for the removal and recovery of contaminated areas, which is based on the ability of organisms to convert toxic substances into less harmful or inert compounds. Here, we evaluate the capacity of the Bacillus subtilis (BS) bacteria to bioadsorved heavy metals such as lead (Pb), copper (Cu) and cadmium (Cd) in water samples. Water samples were laboratory contaminated Pb at 500 ppm, Cu and Cd at 100 ppm. First, the growth curve of BS was plotted using Tryptone Soy Broth (TSB) at 100% (TSB100) and 33% (TSB33). Later, BS was studied in water containing all three metals separately and simultaneously. All solutions were stirred at 150 rpm, 35 ℃ for periods that ranged from 1 to 144 h. The heavy metal analyses were performed by X-ray fluorescence and Inductively Coupled Plasma Mass Spectrometry. The results showed that BS was resistant to Cu, Cd and Pb in water, with active multiplication and reduction in the concentration of the metals. The highest removal efficiency, in the presence of each heavy metal, reached 100% with Pb, 92.3% with Cd and 89% with Cu. In the solution with the mixture of heavy metals, Cd and Pb levels reduced significantly. However, the mixture of metals negatively affected the removal of Cu. In conclusion, the implement using Bacillus-type bacteria can be efficient in the biosorption of heavy metals from aqueous solutions and can be employed as a cost-effective treatment for the bioremediation of industrial effluents and contaminated areas.

Microwave Plasma Atomic Emission Spectroscopy (MP-AES): Alternative Spectroscopy Method for Heavy Metals Analysis in Water

Water is one of the necessities in our daily life, yet its pollution poses risks to human and ecological well-being. In this study, the presence of eight heavy metals in samples collected from two lakes and five tap water sources were investigated using microwave plasma atomic emission spectroscopy (MP-AES). Utilizing an alternative spectroscopy method, MP-AES able to achieve detection limits in the sub-parts per billion (ppb) level. Analysis of the water samples revealed that all eight metals were detected within a concentration range, from undetectable levels up to 0.93 mg/L. Moreover, the recovery on sample spike demonstrated an acceptable range of 107-114 %. These findings underscore the potential of MP-AES as a promising method for the analysis of heavy metals in water, offering valuable insights for water quality assessment and management.

NZVI@BC as a Soil Amendment and Its Effects on Potted Rice Growth and Soil Properties

This study investigated the effects of nano zero-valent iron-modified biochar (nZVI@BC) as a soil amendment on potted rice growth, soil properties, and heavy metal dynamics. Seven treatments with varying amounts of soil conditioner, biochar, and nZVI@BC were applied to potted rice. Results showed that nZVI@BC application significantly improved rice agronomic traits, with the 15 g·kg−1 treatment increasing the panicle formation rate by 15% and 100-grain weight by 8% compared to the control. Soil fertility was enhanced, with available phosphorus increasing from 137 to 281 mg·kg−1 in the most effective treatment. Heavy metal analysis revealed that nZVI@BC application did not increase soil heavy metal content, with Cd levels remaining below 0.3 mg·kg−1 across treatments. Notably, the 10 g·kg−1 nZVI@BC treatment showed potential for slight Cd immobilization, reducing its concentration from 0.32 to 0.26 mg·kg−1. Microbial community analysis showed that nZVI@BC altered soil microbial diversity and composition, with the 10 g·kg−1 treatment resulting in the highest fungal diversity (Chao1 index: 294.219). The relative abundance of the beneficial fungal class Agaricomycetes increased from 40% to 55% with optimal nZVI@BC application. These findings suggest that nZVI@BC has potential as an effective soil amendment for improving rice cultivation while maintaining soil health, microbial diversity, and potentially mitigating heavy metal contamination.

The toxicological analysis and safety assessment of heavy metals (Hg, Pb, Cd, and As) in food for special medical purposes (FSMP) available in Polish pharmacies for oncological patients

The presence of heavy metals in food products may seem an archaic concern; however, our study reveals that the risk is significant, unexpectedly in Food for Special Medical Purposes (FSMP) for oncology patients available in Polish pharmacies. This investigation fills that gap through a detailed toxicological analysis and health risk assessment of these heavy metals in FSMP products (n = 23) using inductively coupled plasma mass spectrometry (ICP-MS). Our comprehensive risk assessment involved evaluating (1) the concentrations of As, Cd, Hg, and Pb in both liquid and powdered FSMP formulations, (2) the amount of heavy metals ingested per serving as specified by the manufacturer, and (3) the cumulative daily and weekly intake adjusted for body weight, benchmarked against the provisional tolerable weekly intake (PTWI). While most samples were below PTWI limits, Cd levels raised concerns due to potential cumulative exposure risks, particularly for oncology patients consuming these products regularly. This study underscores the hidden dangers of heavy metal contamination in FSMP, emphasizing the need for vigilant monitoring and stringent regulatory frameworks to ensure patient safety. By uncovering these latent risks through meticulous toxicological assessment, our research provides crucial insights that could safeguard vulnerable populations. This study is significant due to concerns related to the complex risk assessment of FSMP for cancer patients, considering the complexity of oncological diseases and other comorbid factors, as well as the verification of available legal and regulatory acts of FSMP at the European Community level.

A multi-year heavy metal analysis of 72 dark chocolate and cocoa products in the USA.

Contamination of cocoa containing products, such as dark chocolate, with heavy metals including lead, cadmium and arsenic has been reported in the US. However, a formal exploration into the significance of this contamination, nor multi-year trends in the degree or scope remain unresolved. From 2014 to 2022, 72 consumer cocoa-containing products were purchased and analyzed for heavy metal contamination with lead (Pb), cadmium (Cd), and arsenic (As) in 4 distinct cohorts (2014, 2016, 2019, 2022). The thresholds used to assess heavy metal contamination were set to Prop 65 maximum allowable dose levels (MADLs) of 0.5 mcg/day, 4.1 mcg/day, 10 mcg/day for Pb, Cd, and As, respectively. Our analysis reports that 43, 35, and 0% of the products tested exceed Prop 65 MADLs for heavy metal concentrations, respectively, of Pb, Cd, and As, while 97.2% (70 of 72) fall below US FDA IRL limits established for Pb. Median concentrations of each metal tested were lower than even the conservative Prop 65 MADLs, indicating a potentially large effect of product outliers. This indicates that heavy metal contamination-in more than half of products tested-may not pose any appreciable risk for the average person when consumed as a single serving; however, consuming some of the products tested, or more than one serving per day in combination with non-cocoa derived sources heavy metals, may add up to exposure that would exceed the Prop 65 MADLs. Notably, "organic" products were significantly more likely to demonstrate higher levels of both Cd and Pb.

Assessment of the Impact of Heavy Metals on Clarias gariepinus Burchell and Heterobranchus longifilis Fish Species of Omambala River Basin of Anambra State Nigeria

Heavy metals are natural occurring minerals that are found in nature, as deposits in pure and mostly ore form. They are referred to as transition metals due their variable oxidation state, which as a result have made them to develop special properties among other elements in the periodic table. This study aimed to assess the levels of heavy metals (Lead, Chromium, Mercury, Cadmium, Iron, Zinc, Copper and Magnesium) in Clarias gariepinus and Hetrobrancus longifilis collected from the Omambala River. The fish samples were collected by fishermen at the fish landing site. The heavy metal analysis in the two fish species was studied using Atomic Absorbtion Spectrophotometer (AAS) and the instrument was calibrated with standard solutions. The result of this work showed that the highest compositions of heavy metals were: lead (Pb) content in C. gariepinus was 2.69±1.417 mg/l while in H. longifilis was 3.14±1.395 mg/l. However, Chromium content in C. gariepinus was 3.11±0.826 mg/l and in H. longifilis was 4.04±1.073 mg/l. Mercury in C. gariepinus was 3.98±1.903 mg/l and H. longifilis was 4.77±2.283 mg/l. Cadmium in C. gariepinus was 4.90±2.100 mg/l while H. longifilis was 4.83±2.019 mg/l. Moreover, Iron in C. gariepinus was 3.94±1.414 mg/l and H. longifilis was 4.31±2.077 mg/l. Zinc in C. gariepinus was 4.02±1.917 mg/l and H. longifilis was 5.47±2.607 mg/l. Copper in C. gariepinus was 2.62±0.720 mg/l while in H. longifilis was 3.01±0.828 mg/l. Magnesium in C. gariepinus shows 4.66±2.774 mg/l and H.longifilis shows 3.72±1.466 mg/l. The most prevalent heavy metals from the study were Zn, Cd, Hg, Mg, Fe, Cr, Pb, and Cu. It is therefore recommended that further research be made, and awareness created on the high health risk associated with frequent ingestion of these harmful mineral elements found in trace deposits in the Omambala River by the appropriate authority to ascertain their concentrations.

Microplastics and heavy metal contamination along a land-use gradient in a Himalayan foothill river: Prevalence and controlling factors

The co-occurrence of microplastics (MPs) and heavy metals in aquatic systems has raised significant concerns, yet their relationship in freshwater ecosystems remains poorly understood. This study aims to evaluate the prevalence of MPs and factors controlling their distribution in both water and sediment in the Markanda River, Northwest India. MPs were extracted from sediment and water samples using density separation and classified through fluorescence microscopy and Raman spectroscopy. Metal concentrations in river water samples were analyzed using ICP-MS, and their correlation with MP abundance was explored. The results indicated the widespread occurrence of MP pollution across the Markanda River basin, with particle concentrations ranging from 10 to 530 particles L−1 in surface water and 1330–4330 particles kg−1 dry weight (dw) in sediment samples. The variability in MP abundance at sampling sites along the Markanda River courses results from factors such as the proximity of industrial establishments and human habitation, while the influence of grain size on MP distribution appears to be limited. Pellets (88.5 %) and fragments (8.5 %) were the most abundant types of MPs, with polyethylene (45.45 %) and polystyrene (30.9 %) being the dominant forms in water samples. The ICP-MS analysis of heavy metals in water samples indicated elevated levels of As (1.67 to 32.31 ppb) in downstream areas of the river system, influenced by human activities. While metals exhibited correlation with each other, there was a weak association, except for As, with the levels of MPs in the Markanda River. The SEM-EDX analyses to characterize chemical elements absorbed onto the surface of MP showed distinct variations in upstream and downstream sites, with the presence of elements such as Mn, Ni, Cr, Zn, As, Se, and Cu found in downstream areas. We conclude that MPs contaminated with heavy metals potentially threaten the ecological security of freshwater aquatic systems and highlight the importance of management action to reduce plastic pollution worldwide.

Analysis of heavy metal and arsenic sources in mangrove surface sediments at Wulishan Port on Leizhou Peninsula, China, using the APCS-MLR model

Mangrove forests are sources and sinks for various pollutants. This study analyzed the current status of heavy metal and arsenic (As) pollution in mangrove surface sediments in rapidly industrializing and urbanizing port cities. Surface sediments of mangroves at Wulishan Port on the Leizhou Peninsula, China, were analyzed using inductively coupled plasma emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) for the presence of Cr, Pb, Ni, Zn, Cd, Cu, As, and Hg. The Pollution load index, Nemerow pollution index, and Potential ecological risk index were employed to evaluate the pollutant. Multivariate statistical methods were applied for the qualitative analysis of pollutant sources, and the APCS-MLR receptor model was used for quantification. This study indicated the following results: (1) The average content of eight pollutants surpassed the local background level but did not exceed the Marine Sediment Quality standard. The pollution levels across the four sampling areas were ranked as Ⅲ > Ⅳ > Ⅰ > Ⅱ. The area Ⅱ exhibited relatively lower pollution levels with the grain size of the sediments dominated by sand, which was not conducive to pollutant adsorption and enrichment. (2) The factor analysis and cluster analyses identified three primary sources of contamination. As, Cr, Ni, and Pb originated from nearby industrial activities and their associated wastewater, suggesting that the primary source was the industrial source. Cd, Cu, and Zn stem from the cement columns utilized in oyster farming, alongside discharges from mariculture and pig farming, establishing a secondary agricultural source. Hg originated from ship exhaust burning oil and vehicle emissions in the vicinity, representing the third traffic source. (3) The APCS-MLR receptor model results demonstrated industrial, agricultural, and traffic sources contributing 47.19 %, 33.13 %, and 13.03 %, respectively, with 6.65 % attributed to unidentified sources.

Characterization and Source Analysis of Heavy Metal(loid)s Pollution in Soil of an Industrial Park in Kunming, China

This study investigated the characteristics and sources of heavy metal(loid) pollution in the soil of a key industrial park in Kunming, China. In total, 60 soil samples (40 from agricultural land and 20 from construction land) were collected from and around the park. The soil pH and contents of Arsenic (As), lead (Pb), copper (Cu), zinc (Zn), cadmium (Cd), mercury (Hg), nickel (Ni), and chromium (Cr) were measured. The contents of the eight heavy metal(loid)s were analyzed using the background values of heavy metal(loid)s in the Kunming soil. The pollution load, geoaccumulation, and Nemero Comprehensive Pollution Indices were used for environmental risk evaluation. Cluster and principal component analyses were used to resolve heavy metal(loid) sources. Cd was enriched in construction and agricultural soils. As, Hg, Cd, Pb, Cu, and Zn exhibited large spatial differentiation and were significantly affected by the external environment. A regional pollution load index of 3.02 indicated overall heavy pollution. The pollution load index for each heavy metal(loid) indicated light pollution. The geoaccumulation index indicated relatively severe As, Cd, Cu, Pb, and Zn pollution. The Nemero Composite Pollution Index value showed that the study area was heavily polluted, with construction land being mildly polluted by Cd, and agricultural land being moderately polluted. The results of the spatial distribution show that there were high levels of contamination in the center. Correlation and principal component analyses showed that the pollution sources of the eight heavy metal(loid)s varied. Hg, Cd, and Pb originate primarily from industrial and agricultural pollution. Traffic sources significantly impacted Cu, Pb, Cd, and Cr. Natural sources are the main sources of Cr, Ni, and Cd. Ni is also affected by industrial sources, whereas Zn and Cu are affected by agricultural pollution. The influences of As, Cd, and Pb on the surface soil in the study area were more serious. Cd is more widely polluted and should be a priority in controlling soil heavy metal(loid)s.

Heavy metal analysis of wild edible mushrooms grown in Türkiye and assessment of possible carcinogenic and non-carcinogenic risk

In this study, heavy metals (HM) composition of in seventy-three wild edible mushroom (WEM) species collected from unpolluted areas in fourteen provinces of Türkiye was determined by X-ray fluorescence spectrometry. The concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Cd, Hg, Pb and As analyzed in WEM species varied from 1.1 to 76.3, 13.8–822.7, 9.5–8867.0, < 3.0–31.8, 5.1–44.4, 3.8–380.2, 17.9–912.0, < 0.5–19.5, < 0.8–4.9, < 0.9–15.6, < 0.8–31.9 and < 0.5–257.4 mg/kg dry weight, respectively. The concentrations of Cd and Pb were higher than the limits recommended by the Turkish Food Codex for cultivated mushrooms. The potential carcinogenic and non-carcinogenic risks caused by the ingestion of WEM species containing HMs were assessed by estimating the hazard and total cancer risk index. Non-carcinogenic risk assessment reveals no risk for consumption of the studied WEM species for adult consumers, except for two WEM species. On the other hand, 26 % of the values of the total cancer risk index assessed for Cr, As, Pb, and Ni in WEM species exceed the acceptable limit (≥ 10−4).

Methods for analysis and monitoring of heavy metals in the environment

This review surveys capabilities of modern instrumental analytical methods that provide low limits of detection for a wide range of elements. Some elements have their own toxic forms, so their identification is of particular importance. Researchers pay increased attention to the content of cadmium and lead due to their high immediate and delayed toxicity.It should be noted that those instrumental methods of analysis that are used to determine these important ecotoxicants are often used to determine other heavy metals. The following objects of analysis are considered – natural, river, sea waters; brines; bottom sediments; plants, including medicinal ones; precipitation; soil; as well as whole blood and blood serum; hair and animal fur; animal organs and tissues. Special attention is paid to eliminating matrix influences and reducing limits of detection using concentration procedures. Various types of extraction, sorption, precipitation, chemical transformation (hydride generation, etc.) are considered and applied to biological and environmental objects.The capabilities of modern instrumental methods of analysis for the determination of heavy metals and important ecotoxicants are considered and compared – single‐element (ETAAS, IVA, etc.) and multi‐element (ICP AES, ICP MS, XRF, etc.). The data is structured in the form of a table, which shows specific analysis methods, indicating the method of sample preparation and/or features of instrumental determination, a list of elements to be determined and the limits of detection.

The spatial distribution and source of heavy metals in soil-plant-atmosphere system in a large coal mining area

Due to the lack coupling analysis of heavy metals in soil-plant-atmosphere system, the migration and transformation of heavy metals remains unclear. In this study, 240 surface (0–20 cm) soil samples, 365 plant samples and 168 atmospheric dust samples were collected in a large coal mining area, in which selected heavy metals arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), plumbum (Pb), zinc (Zn) were analyzed, to elucidate the spatial distribution and source of heavy metals and their bioavailability. According to the results of ArcGIS mapping analysis, the distribution patterns of Cd, Cu, Pb, and Zn in the three media are similar, while the distribution characteristics of Cr and Ni are highly consistent. The factors contributing to these spatial distribution characteristics of heavy metals could be associated with human activities and the characteristics of the elements. Compared with the background value, Zn, Cr, Pb in soil, Zn, Cr, Cu in plants and Zn, Pb, Cu in atmospheric dust apparently accumulated. The geological accumulation pollution index (Igeo) shows that there exist mild to moderate levels of Cr and Cd pollution in soil, and mild to moderate levels of Cd, Cr, Pb, and Zn pollution in the air. The evaluation of potential risks of heavy metals showed moderate ecological hazards in soil and strong ecological hazards in atmospheric dust. The sources of heavy metals were assessed using principal component analysis (PCA), land use type, and spatial analysis. Anthropogenic factors are the main sources of heavy metal content. Coal-related industrial processes related to coal, sewage irrigation, the use of agricultural chemicals, and vehicle emissions may be anthropogenic sources of heavy metals.

Comparison analysis of bioactive constituents and heavy metals among original plants of Kuding tea from the genus Ilex

Kuding tea (KT) is the general name of a set of bitter-tasting herbal tea made from varied original plant species. However, limited information was reported about the difference of bioactive constituents, heavy metals, and bioactivities among those original species. In the present study, comparison analyses among heavy metals, polysaccharides, phenolics, flavonoids, and saponins constituents, as well as the antioxidant and antidiabetic activities were performed through colorimetry, UPLC-QTOF-MS, enzymatic assay and molecular docking techniques on the six KT original plants mainly from the genus Ilex. Results showed that Cd contents in the four KT original plants other than Ilex pubescens (IP) and Ilex cornuta (IC) and heavy metal contents including Pb, Cu, As and Hg in the all six plants were lower than standard limit values. Furthermore, contents of carbohydrate in polysaccharides (470.06 and 548.51 mg GLE/g), total phenolics (33.84 and 48.85 mg GAE/g), flavonoids (30.86 and 109.97 mg RE/g), phenolic acids (49.68 and 61.48 mg CAE/g), flavonols (18.47 and 19.19 mg RE/g), flavanols (0.18 and 0.14 mg CE/g), saponins (90.81 and 97.33 mg GSE /g) in IP and Ligustrum japonicum (LJ), as well as their antioxidant activity levels (IC50 607.41–780.44, and 547.06–754.00 mg/L) were all significantly higher than those in other four KT original plants. Moreover, a total of 6 and 9 compounds were tentatively characterized from IP and LJ, respectively, and molecular docking and molecular dynamics simulation were further used to analysis the interaction between α-glucosidase and bioactive compounds in IP. At last, principal component, hierarchical cluster, and correlation analysis indicated that carbohydrate content of polysaccharides, total phenols, flavonoids and phenolic acids were the main influencing factors to antioxidant abilities. Overall, according to our systematic analysis, IP possessed the highest antioxidant and antidiabetic potentials, thus might be a better KT original plants from the genus Ilex for further development and utilization.

Migration Characteristics Analysis of Heavy Metal in Oil Shale Based on In-situ Core Seepage Experiments

Migration Characteristics Analysis of Heavy Metal in Oil Shale Based on In-situ Core Seepage Experiments

Predicting heavy metal transport in groundwater around Lemna dumpsite: implications for residence utilizing borehole water in Cross River State, Nigeria

Groundwater is considered the most important natural resource to mankind. Groundwater constitutes an important part of the hydrological cycle and is more prone to pollution. Dumpsite located in close proximity to groundwater resources is highly susceptible to leachates pollution. Predicting the susceptibility of groundwater pollution is crucial to address industry-standard codes for groundwater flow, contaminant transport, local to regional-scale water quality, and source water protection issues. Therefore, predicting heavy metal transport in groundwater around Lemna dumpsite in Cross River State, Nigeria, was examined. Soil samples were purposively collected with a soil Auger, along a straight line at (5 m, 25 m and 50 m) in the dumpsite. Water samples were purposively collected from five (5) boreholes close to Lemna dumpsite. The study utilized pumping test method to obtain data for the analysis of heavy metal transport in groundwater. Data analysis of the laboratory results of soil and borehole water quality focuses on arsenic, lead, cadmium, chromium, nickel, and mercury. Paired sample t test was used to analyse the soil and borehole water quality. Visual Modflow was also used to analyse the solute transport of heavy metals in groundwater around Lemna dumpsite. The paired sample t test of the analysis of heavy metals in soil exhibited a significant difference (p < 0.05) compared to National Environmental Standard Regulation and Enforcement Agency limits. The paired sample t test of the analysis of heavy metals in borehole water exhibited a significant difference (p < 0.05) compared to World Health Organization limits. The significant level indicates contamination of the soil and borehole water. The findings revealed a spatial spread of 259.2000 m2/day, with the contaminant travelling up to 94,608 m2/year. The extent of heavy metals concentration exhibited a maximum of 0.991 mg/l to a minimum of (− 6.72 × 10–18 mg/l), with concentrations decreasing as the plume extend. The study recommends the need for remediation and stringent monitoring to mitigate heavy metal contamination of boreholes near Lemna dumpsite.

Global assessment of Algerian honeys quality by palynological, physicochemical analyses, trace elements and potentially toxic elements screenin

The quality of twenty Algerian honeys was assessed based on their palynological and physicochemical properties, and their trace and toxic elements composition. A qualitative pollen analysis was conducted to estimate the botanical origin. The physicochemical analyses included moisture content, pH, electrical conductivity, 5-hydroxymethylfurfural (HMF), colour, and the content of 3 sugars (fructose, glucose, and sucrose). The analysis of mineral and heavy metals included Zn, Mn, Fe, Cu, Cr, Ni, Pb, Cd, and As. The pollen spectrum showed a great diversity with 60 taxa identified. The palynological analyses revealed the presence of 15 honeys with pollen dominance (unifloral): Citrus sp., Eucalyptus sp., Ziziphus lotus (L.) Lam., Sinapis arvensis L., Dorycnium sp., Bupleurum sp., Echium sp., Lotus sp., and 5 honeys without pollen dominance (polyfloral). The physicochemical results showed that the samples conform to international quality standards, with few exceptions related to HMF, mainly due to beekeeping practices. The colour was from water white to dark amber. Pb and Cd concentrations were found to be below the maximum residue limits set by the European Directive with which the toxic elements were compared. These results would contribute to the assessment of Algerian honey and provide a database for the regulation of honey trade and consumer protection.