Concentrations Of Metal Elements Research Articles

Magnetic response and bioaccessibility of toxic metal pollution in outdoor dustfall in Shanghai, China

Toxic metal content testing, environmental magnetic monitoring and in vitro bioaccessibility experiments each have their own advantages and are often used independently for environmental monitoring, but there are few studies that combine the three to evaluate the hazards of toxic metals to humans. This paper investigated the total content, magnetic properties and bioaccessibility of nine potentially toxic metal elements (Zn, Sn, Pb, Cu, Fe, Ni, Cr, Sr, Mn) in dustfall from different functional zones in Shanghai, China, and systematically compared the related results. The results show that these nine metal elements have different degrees of contamination and enrichment in outdoor dustfall, and their content distribution shows the following trend: Zn>Sn>Pb>Cu>Fe>Ni>Cr>Sr>Mn. Magnetic characteristics χlf and SIRM are mostly positively correlated with the metal elements, indicating that the higher the content of magnetic minerals in the sample, the higher the concentration of metal elements. It was also found that χlf, SIRM, and χARM can well reflect the characteristics of dustfall pollution. The magnetic minerals have a certain degree of enrichment, and the particle size of the magnetic minerals is relatively coarse, mainly in the form of coarse multi-domain and pseudo-single-domain particles, which are largely derived from anthropogenic pollution. The χlf and PM10 concentrations in the precipitation show relatively similar spatial trends, so χlf, SIRM, and χARM can be used as air pollution indices to facilitate the evaluation of metal elements pollution in dustfall. The overall trend in gastric bioaccessibility is Pb>Zn>Mn>Cu>Cr. Due to the increase in the pH of digestive fluid, the bioavailability of toxic metals decreases significantly from the gastric stage to the intestinal stage. χlf, SIRM, and χARM/SIRM are all related to the bioaccessibility of toxic metals in the intestinal stage, so they can be used as toxicity indicators to evaluate the bioaccessibility of toxic metals in dustfall.

Analysis of heavy metal characteristics and health risks of edible mushrooms in the mid-western region of China

This study determined the content of metal elements (As, Cd, Cr, Hg, Pb) in 9 edible mushrooms using ICP-MS, and evaluated the harm of long-term consumption of edible mushrooms to human health. The results showed that the concentrations of metal elements decreased in the order of Cd > As > Cr > Pb > Hg in edible mushrooms. The concentrations of Cd, As, Pb, and Hg were 22.95%, 8.20%, 1.64%, and 3.28% higher, respectively, than the maximum standards in China, whereas Cr did not exceed the limit. The detection rate of metal elements in Morchella esculenta (L.) Pers (M. esculenta), and Agaricus blazei Murill (A. blazei) were relatively high. The results of single factor evaluation and target hazard coefficient (THQ, HI) indicated that Dictyophora indusiata (Vent.ex Pers) Fisch (D. indusiata), A. blazei and M. esculenta were the main sources of risk. In addition, the HI values in ascending order were: Pb (0.43) < Cr (0.68) < Hg (0.92) < Cd (7.21) < As (14.02), indicating that Cd and As were the primary sources of health risks in edible mushrooms. To ensure food safety, it is recommended to strengthen the supervision of edible mushrooms, make reasonable choices, and reduce exposure levels of heavy metal pollution.

Assessment of contamination levels, potential ecological and human health risks due to trace elements pollution in the vicinity of the Lolodorf uranium deposit, Southern Cameroon.

The current study assessed the contamination levels and associated ecological and health risks due to hazardous trace elements in soils from Awanda and Mvengue, located in the vicinity of the Lolodorf uranium deposit in Southern Cameroon. Qualitative and quantitative analyses of the soil samples were performed using energy-dispersive X-ray spectrometry. The results indicated that the mean concentrations of metallic and trace elements in soil samples increased in the following order: U < As < Th < Pb < Cu < Ni < Zn < Cr < Mn < Fe < Al. The average concentrations of U, As, Th, Pb, Cu, Ni, Zn, Cr, Mn, Fe, and Al ranged between 0.9-3, 2.9-3.8, 9.2-15, 13.1-20.3, 11.5-42.5, 31.1-60.7, 42.9-91.6, 94.50-170.9, 100.45-500.57, 4874.8-88340 and 226147.5-324240.0mg/kg, respectively. The contamination levels of trace elements were assessed and the human health risk of chemical elements was determined. The investigated elements' average contamination factors (CF) results showed the highest mean CF recorded for Al followed by Cr, Th, Pb, Zn, Cu, Ni, Fe, U, Mn, and As. Furthermore, the findings showed that 90% of soil samples can be classified as considerably contaminated with Al, 100%, and 60% as moderately contaminated with Cr and Th, respectively. The Geo-accumulation indices of Mn, Cr, Th, U, Ni, Zn, Cu, As, and Pb were lower than 1, suggesting low contamination levels for these elements. The ecological factors and risk indices indicated a low ecological risk in the investigated area. In terms of human health risk, ingestion was identified as the primary pathway for both carcinogenic and non-carcinogenic risks, with children found to be more exposed to both risks than adults. Al, Cr, and Fe were found to be the main contributors to non-carcinogenic health risks, while Cr and Ni were the main contributors to carcinogenic health risks.

Trace Metal Elements (TMEs) in Groundwater Around the Former Industrial Gold Mine of Poura in Burkina Faso – West Africa

The objective of this study is to assess the quality of groundwater around the first industrial mine in Burkina Faso, whose activities have been closed since 1999. The diagnosis of pollution by trace metal elements of groundwater around the old Poura gold mine was carried out through the determination of the contents of Trace Metal Elements (TME) at MP-AES and the measurements of the physicochemical parameters in situ on 38 samples of borehole water. These data made it possible to calculate the pollution risk index, to establish correlations between the different physicochemical parameters on the one hand and with the trace metal elements on the other hand, from the Pearson matrix and to carry out a multivariate statistical analysis, in particular that in principal components (PCA), with a view to determining the origin of the polluting elements. The results obtained made it possible to identify four samples of groundwater with an acidic pH (GWF18 (6.44), GWF19 (6.39), GWF23 (6.1) and GWP01 (5.99)) and 34 samples of groundwater whose Cd, Al, Fe, As, Pb, or Hg contents are higher than the standards in force in Burkina Faso. The Pollution risk Index (PI) indicates that 35 groundwater samples are slightly polluted and 3 groundwater samples are very heavily polluted (GWP01 (PI = 456%), GWF06 (PI = 132.5%), GWF03 (PI = 105.1%)). The Pearson correlation matrix and the principal component analysis (PCA) show that the origin and mobilization of the trace metal elements involved (Al, As, Cd, Cr, Fe, Hg and Pb) are linked to natural mineralization and anthropogenic activities such as mining and agricultural activities, favored by the infiltration of water into the subsoil through geological structures such as fractures and faults.

Black powder and mineral deposits in the LPG production and processing line: Analytical study and formation mechanisms

The accumulation of mineral deposits such as black powder causes severe impacts throughout the gas production and transport process. The phenomenon takes place from gas wells to LNG/LPG treatment plants and terminals. The complexity lies in understanding the mechanisms by which these materials are formed in random quantities, as well as their varied nature. The aim of this study is to monitor black powder and other mineral deposits formation in a chain of gas production and processing situated in the south of Algeria and unravel their root causes. To that extent, an analytical study was carried out on four samples of both mineral deposits and black powder taken from an LPG processing and production unit. The adopted analytical approach included an exploration of the textural and structural properties. It also involves a composition characterizations related to the content of metallic elements, moisture, organic and mineral matter. The particle distribution is also determined. The analytical study was conducted using gravimetric determination, XRD, XRF, SEM/EDX and Raman spectroscopy. Particle distribution was given by Laser granulometry technique. The results of the DRX/FRX and EDX characterization primarily revealed that the samples contain a variety of mineral components such as iron oxides; magnetite Fe3O4 and hematite Fe2O3, iron oxy-hydroxide FeO(OH), iron sulphide FeS2, calcite CaCO3, SiO2 and halite NaCl. The presence distribution of these components depends on the location of the sample in gas line. Granulometry study shows that black powder contamination can be spread over a wide spectrum of particle sizes ranging from 1.51 µm to 678.50 µm. This study has allowed to elucidate the nature and distribution of particles deposited at different positions in the LPG production chain and to propose probable mechanisms for their formation.

Susceptibility and Metallics Elements in Soil Struck by Lightning in West Kotawaringin Regency, Central Kalimantan

Abstract Magnetic susceptibility is a magnetic parameter that assesses a magnetic material’s susceptibility to external magnetic fields. Magnetic susceptibility values can determine the properties of magnetic minerals related to the elements they contain. This research aims to determine the value of magnetic susceptibility and metal element content in soil struck by lightning in West Kotawaringin Regency. Sample measurements were performed using the Bartington MS2B instrument to determine the magnetic susceptibility value and XRF (X-ray fluorescence) to determine the metal element content in the soil samples. The magnetic susceptibility value obtained for sample A with low frequency (&lt;10 strikes per month) was 26.1 x 10−8 m 3/kg; for sample B with medium frequency (11–200 strikes per month), it was 538.4 x 10−8 m 3/kg; and for sample C with high frequency (&gt;20 strikes per month), it was 24.4 x 10−8 m 3/kg. Fe (388,000 mg/kg) was the most prevalent metal element in samples B and C, while element V (300 mg/kg) was the least prevalent in sample A. The sample with the highest metal element content was Fe (388,0 mg/kg), while sample A had the lowest metal element content, V (300 mg/kg). The highest correlation value between magnetic susceptibility and metals is 0.9 (K); 0.96 (Cr); 0.98 (Fe); and 1.00 (Ca, Ni, Zn, and Re).

Exploring ultrafine particle emission characteristics from in-use light-duty diesel trucks in China using a portable measurement system

Diesel vehicle exhaust is one of the major contributors to ultrafine particles (UFPs) in urban areas in China. However, there is still a lack of knowledge about UFPs emission characteristics from current in-use diesel vehicles. This study has carried out an on-road test of 10 in-use Light-duty Diesel Trucks (LDDTs) with different emission control standards in China using a self-established portable measurement system based on the Electronic Low-pressure Impactor (ELPI) and characterized the ultrafine particle number (PN) concentration, particle size distribution and metal element contents. The results revealed a significant reduction of 93.37% in the average PN0.1 emission factor of LDDTs from China IV to China VI. Notably, LDDTs compliant with the China VI vehicle emission control standard exhibited the lowest PN0.1 and PM0.1 emission factors, measuring 4.991×1014 #/km and 0.627 g/km, respectively. By taking into account emissions under real driving conditions, we found that the PN emission rates grow with the increase of the Vehicle Specific Power (VSP). The cold-start phase had higher PN emissions than the hot-start phase, with 8590, 1890, 477, and 22 times higher than those of the ambient air (1.18×105 #/cm3), respectively. The installation of Diesel Particulate Filter (DPF) can decrease UFPs by more than 99.8%, while the PN emission factor during the DPF regeneration stage (1.85×1016 #/km) increased by 5 orders of magnitude that of the DPF normal works (7.51×1011 #/km). Metal element contents analysis shows that Fe, Ca, Al and Mg are the dominant elements in UFPs of LDDT exhaust gas, but the element of Ni is slightly increasing in a China VI, possibly due to the new automotive engine exhaust manifolds being made of Ni instead of cast iron for the purpose of having more high-temperature resistance. Our study demonstrates the importance of monitoring and routine maintenance of exhaust after-treatment systems.

Facile synthesis of in situ bismuth-doped calcium phosphate nanocomposite integrated injectable biopolymer hydrogel slurry for bone regeneration

The bionics of natural bone structures plays an essential role in the selection of materials for bone tissue engineering. Although the content of trace metallic elements in bone is low, they have significant effects on the process of bone growth and metabolism. Up to now, the applications of “green” heavy metals in bone regeneration are limited. Herein, in this study, we present a straightforward one-pot strategy for the synthesis of in situ bismuth-doped amorphous calcium phosphate nanocomposites (RBCP), effectively integrating the beneficial properties of each component. The characterization of these products can be readily optimized by adjusting reaction parameters. Our in vitro studies show that under coordination of each component, the RBCP biomaterial demonstrates distinguished biocompatibility and significantly accelerates vascular pattern formation within just 4 h by stimulating the expression of angiogenesis-related genes in human umbilical vein endothelial cells (HUVECs). In vivo experiments indicate that the incorporation of bismuth effectively enhances bone regeneration and osseointegration in a rat femur defect model. In conclusion, the as-prepared RBCP biomaterials hold promising prospects for treating segmental bone defects, owing to the facile, cost-effective, and eco-friendly preparation process, along with their remarkable capabilities.

Content, Sources, and Ecological Risk Assessment of Heavy Metals in Soil of Typical Karst County

Soil heavy metals in karst areas have obvious high background value characteristics. Conducting county-level soil heavy metal ecological risk assessment and identifying heavy metal sources in karst areas are of great significance for soil pollution control and land resource management. Taking Pingguo City, a typical karst county in Guangxi Province, as the study object, 3 151 surface and deep soil samples were collected using the grid method and combined to form 785 analytical samples. The contents of eight heavy metal elements, including As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, were determined. The content characteristics and sources of heavy metals were analyzed using statistical analysis, interpolation analysis, factor analysis, and the absolute principal component-multiple linear regression model （APCS-MLR）. Using the content of heavy metal elements in deep soil （150-200 cm） as background values, the ecological risk assessment of heavy metals in surface soil （0-20 cm） in the study area was conducted using the geo-accumulation index （Igeo） and potential ecological risk index （RI） methods. The results showed that the average content of heavy metal elements in the deep soil of the study area was significantly higher than the background value of the C layer soil in Guangxi Province, and the average content of heavy metal elements in the surface soil was significantly higher than the background value of the A layer soil in Guangxi Province. The spatial distribution of soil heavy metal element content generally showed the characteristics of high in karst areas and low in non-karst areas. The main sources of As, Cr, Ni, Pb, and Zn were soil parent materials, with contribution rates of 74.36%, 84.59%, 93.69%, 79.67%, and 78.17%, respectively. The main sources of Cd were soil parent material sources and unknown sources, with contribution rates of 37.33% and 31.05%, respectively. The main sources of Cu were soil parent materials and unknown sources, with contribution rates of 59.07% and 40.23%, respectively. The main sources of Hg were tectonic activity and mineralization, as well as unknown sources, with contribution rates of 52.49% and 30.65%, respectively. The geo-accumulation index （Igeo） showed that the surface soil was mainly polluted by Cd, with mild or above pollution accounting for 47.78%. The potential ecological risk index （RI） showed that the proportion of surface soil heavy metal comprehensive potential ecological hazards with mild, moderate, strong, and very strong levels was 80.78%, 14.97%, 2.51%, and 1.64%, respectively.

Determination and safety evaluation of metal element contents of Oviductus Ranae produced from &lt;i&gt;Rana dybowskii&lt;/i&gt; by pond culture–forest grazing relay model in Heilongjiang Province, China

The aquatic products of grazing ecological culture exhibit a strong reliance on the production environment system, which may result in heavy metal contamination. In this study, 24 elements (Ag, Al, As, Ba, Cd, Co, Cr, Cs, Cu, Fe, Ga, K, Mg, Mn, Na, Ni, Pb, Rb, Se, Sr, Tl, U, V, Zn) were determined for Oviductus Ranae (OR) from more than 1,000 individuals of Rana dybowskii produced by pond culture–forest grazing relay mode from six major production areas in Heilongjiang Province, China. Furthermore, we assessed the associated health risks. Our findings indicate that most of these 24 metal elements were detected in OR at a detection rate of 100%, with the exceptions being As (98.0%), Ga (98.0%), Co (98.0%), V (94.0%), Cd (89.0%), Pb (76.0%), Cs (74.0%), Tl (35.0%), and U (not detectable). Variations in element concentrations were significant across the six sampling sites, with characteristic elements identified to account for spatial differences. The total target hazard quotient was determined to be 0.152 in Heilongjiang Province, thereby suggesting a relatively low health risk associated with consuming OR from this region’s production systems according to existing standards and guidelines. Nevertheless, special attention is needed for monitoring the habitat environments of R. dybowskii from two sampling locations showing heightened pollution levels.

Selective extraction of Li and Mn from spent lithium-ion battery smelting slag: Insights from isomorphous replacement in minerals

Recycling the high content of valuable metal elements contained in spent lithium-ion batteries (SLIBs) has attracted significant interest. By leveraging the concept of substitution of isomorphous replacement in earth minerals, this study proposes a novel approach for the selective extraction of Li and Mn from the artificial spodumene-type lithium-rich slag comprising LiAlSi2O6 and Mn2SiO4 through two-step selective roasting process with Na2SO4 and CaCl2, respectively. The thermodynamic calculations confirmed the feasibility of selective Li extraction by Na2SO4 roasting, with the experimental results showing that over 99 % Li was preferentially extracted as LiNaSO4. In the subsequent CaCl2 roasting step for Mn recovery, the Mn2SiO4 was effectively transformed into soluble Na2MnCl4, achieving a maximum Mn extraction efficiency of 86.5 %. The leaching kinetics of the Na2SO4 roasting products were investigated, revealing that the leaching of Li was governed by diffusion and chemical reactions in line with the shrinking core model. Characterization methods such as XRD, SEM, XPS, and TG-DSC were employed to reveal the phase transformation mechanisms of Li and Mn during Na2SO4 and CaCl2 roasting, respectively. The proposed process introduces a novel paradigm for its remarkable selective recovery of Li and Mn from SLIBs smelting slag.

Comparative Analysis of Locally Sourced Adsorbents for Iponda and Idominasi, Abandoned Gold Mine Wastewater Bioremediation in Osun State, Nigeria

This study investigates and compares the effects of Neem leaf (NL) and coconut husk (CCH) adsorbents in reducing the levels of heavy metal concentration and elemental content in wastewater from two specific abandoned gold mining sites, namely Iponda (Iponda wastewater- IPWW) (longitude 4°43'18''E, Latitude 7°43'57''N ) and Idominasi (Idominasi wastewater -IDWW) (longitude 4°42'0''E, Latitude 7°40'59''N). Preparation of locally sourced adsorbents, bioremediation process through adsorption and physico-chemical analysis of the treated wastewater samples were carried out. Adsorbents were prepared from washed, air-dried neem leaves, grinded to 40 microns size to facilitate penetration of the adsorbate. In addition, washed and airdried CCH was carbonized in an electric muffle furnace at between 300 0C and 350 0C over a period of 30 minutes, and then granulated and sieved with a mesh size of 40 µm to ensure uniform size. Measured dosages of adsorbent (0.5 g, 0.75 g, and 1 g) were added to a 50 ml volume of wastewater and the mixture was agitated at different speeds ranging from 30 rpm to 120 rpm. The treated wastewater samples were then subjected to various physico-chemical analytical tests to determine the effect of the adsorbents on the reduction of the heavy metal concentration and elemental content of the wasted water samples. The results of this study demonstrate that both NL and CCH adsorbents have a significant impact on the wastewater from the two abandoned gold mining sites, IPWW and IDWW. This impact is reflected in the reduction of heavy metal and other element concentrations in the wastewater. Furthermore, it can be concluded that the bioremediation process is more effective when utilizing NL compared to carbonized CCH. Locally sourced cheap non-edible biomass materials hitherto considered as wastes have proved to be highly effective and efficient when used as adsorbents in the treatment of wastewater from abandoned gold mining sites. This is evident from the results obtained from this study.

Plant growth promoting endophyte modulates soil ecological characteristics during the enhancement process of cadmium phytoremediation

Endophyte assisted phytoremediation of cadmium (Cd) contaminated soil represents a promising strategy. However, the precise soil ecological regulatory mechanisms by which endophyte enhance the Cd phytoextraction remain unclear. Here, we employed the plant growth promoting endophyte (PGPE) Pseudomonas sp. E3, which has been validated to effectively enhance Cd extraction in Solanum nigrum L., to investigate its regulatory mechanism on soil ecology. The results demonstrated that while PGPE inoculation resulted in minimal alterations to the physicochemical properties of the bulk soil, it led to a notable increase in acid phosphatase activity by 17.86% and urease activity by 24.85% in the rhizosphere soil. This, in turn, significantly raised the available nitrogen and phosphorus contents by 16.93% and 21.27%, respectively, in the rhizosphere soil. Additionally, PGPE inoculation effectively replenished the bioavailable fractions of Fe and Cd, which had been depleted due to root uptake. Importantly, the inoculation specifically augmented the abundance of biomarkers p_Patescibacteria, f_Saccharimonadales, and g_Saccharimonadales in the rhizosphere soil. These biomarkers exhibited a significant positive correlation with the available nutrient and metal element contents. Moreover, the co-occurrence network analysis demonstrated that the inoculation resulted in a simplified bacterial community network, which may have facilitated community synergism by displacing bacteria with a negative association. This regulation appears to occur independently of PGPE colonization. Overall, our findings suggested that PGPE also exerts a regulatory influence on soil ecological features, significantly aiding hyperaccumulators in nutrient acquisition and heavy metal accumulation.

Determination Ca, Cu, Fe, Mn, and Zn release from food in simple gastrointestinal extraction test

In this study, by conducting simulated in vitro digestion experiments on samples, the extraction rates of several essential metal elements in some common food ingredients were determined to guide a rational and balanced diet. At the same time, taking vegetables as an example, the research investigated the impact of food preprocessing on the extraction rates of metal elements within them, demonstrating that the influence of heat treatment varies for different element extraction rates. A wet digestion system using nitric acid-hydrogen peroxide was established for seafood and vegetable samples, and an analytical method for determining Ca, Cu, Fe, Mn and Zn using inductively coupled plasma optical emission spectrometry (ICP-OES) was developed. The detection limits of the method ranged from 0.0003 mg L−1 to 0.1567 mg L−1, with RSDs between 0.004% and 7.161%. The measured contents of several important metal elements in standard substances were largely consistent with national standards, confirming the accuracy and precision of the method. Based on wet digestion, the contents of various metal elements in simulated digestive fluids were determined. The detection limits for the simulated digestion method ranged from 0.0005 mg L−1 to 0.0077 mg L−1, with RSDs between 0.001% and 8.839%, verifying the precision of the method. Consequently, the extraction rates of metal elements in the two types of samples were obtained, leading to the conclusion that vegetable samples are more easily digested compared to seafood, releasing their metal elements. Moreover, the extraction rates of different elements vary within the same type of sample, and the extraction rates of the same element also differ across different samples. For dried fruit samples, a dry ashing digestion system was established, and an analytical method for determining Ca, Cu, Fe, Mn and Zn using ICP was developed. The detection limits of this method ranged from 0.0003 mg L−1 to 0.0073 mg L−1, with RSDs between 0.001% and 1.076%, and the spiked recovery rates were between 85.43% and 105.96%, confirming the accuracy and precision of the method. Based on dry ashing digestion, the contents of various metal elements in simulated digestive fluids were measured, which led to the determination of the element extraction rates. Among these, the extraction rates for Ca, Cu, and Mn were relatively high.

Extensive ICP-MS and HPLC-QQQ detections reveal the content characteristics of main metallic elements and polyphenols in the representative commercial tea on the market.

The content of polyphenols and metal elements in tea has an important impact on the choice of consumers. In this study, we conducted a comparative analysis of ten elements including Fe, Mg, Al, Zn, Cu, Mn, Ni, Cr, Pb, and As in 122 representative tea samples from 20 provinces. The results showed that the difference of metal content among six tea categories was greater than that among provinces, and the overall metal content of black tea was relatively higher. The contents of all elements from high to low were: Mg > Mn > Al > Fe > Zn > Cu > Ni > Cr > Pb > As. The contents of Ni, Fe, Al, Zn and Mn showed significant differences among multiple types of tea categories. While the detection rates of Pb and As were 10.7 and 24.6%, respectively. The contents of all elements were in line with the national limit standards. Meanwhile, the relative contents of theanine, caffeine and a total of 53 polyphenolic compounds in 122 tea samples were detected. The analysis showed that the content of these compounds differed least between green and yellow tea, and the largest difference between black tea and oolong tea. This study provides important support for consumers to choose tea rationally.

Exploring the characteristics and source-attributed health risks associated with polycyclic aromatic hydrocarbons and metal elements in atmospheric PM2.5 during warm and cold periods in the northern metropolitan area of Taiwan

Polycyclic aromatic hydrocarbons (PAHs) and metal elements are commonly considered hazardous air pollutants due to their toxic, mutagenic, and carcinogenic properties. However, few studies have simultaneously examined their potential sources and health effects. This study aimed to quantify the PAHs and metal elements in atmospheric PM2.5, investigating their characteristics and potential sources to assess associated health risks in the northern metropolitan area of Taiwan. The measurements indicated that the mean concentrations of total PAHs and metal elements in PM2.5 were 0.97 ± 0.52 ng m−3 and 590 ± 200 ng m−3, respectively. Utilizing the positive matrix factorization profiles, the PAH pollution was classified into two sources: industrial emissions, traffic emissions, and coal combustion (69%) were the predominant sources of PAHs, with petroleum volatilization and biomass burning (31%) making a lesser contribution. Similarly, we traced metal elements to three potential sources: natural sources (48%), a combined source of industrial emissions, coal combustion, and traffic exhaust (32%), and a blend of non-exhaust emissions from traffic and waste incineration sources (20%). Results from the potential source contribution function model suggested that the emissions of PAHs and metals could be influenced by the eastern regions of China, although local sources, including waste incinerators, traffic, shipping, and harbor activities, were identified as the primary contributors. Source-attributed excess cancer risk revealed that industry, traffic, and coal combustion had the highest cancer risk posed by PAHs in the cold period (1.0 × 10−5), while the greatest cancer risk among metal elements was linked to non-exhaust emissions from traffic and waste incineration emissions (2.0 × 10−5). This research underscores the importance of considering source contributions to health risk and emission reduction when addressing PM2.5 pollution. These findings have direct implications for policymakers, providing them with valuable insights to develop strategies that protect public health from the detrimental effects of PAH and metal element exposure.

A Ubiquitin‐Competitive Strategy Based on the Element Microenvironment to Treat Osteoarthritis

AbstractRecent research on ferroptosis and cuproptosis has underscored the crucial role of trace element regulation in osteoarthritis (OA) treatment. However, research systematically addressing the alterations in nutrient elements in OA cartilage is lacking. This study is initiated using clinical specimens to quantify metal element concentrations in both damaged and intact cartilage to identify deficient trace elements within the inflammatory and senescent microenvironments of OA. Based on the preliminary findings of selenium (Se) and gallium (Ga) deficiencies in OA cartilage, tailored nanoparticles based on Se and Ga are designed and validated for their antioxidant ability. GaSex nanoparticles demonstrated significant efficacy in mitigating chondrocyte degeneration and extracellular matrix degradation induced by inflammatory factors and in alleviating cartilage abrasion, hyperalgesia, and abnormal gait in a destabilization of the medial meniscus (DMM) mouse model. Mechanistically, GaSex nanoparticles activated the Nrf2 pathway and competitively inhibited the ubiquitin‐mediated degradation of Gpx4, thus inhibiting ferroptosis. This study systematically designed GaSex nanoparticles based on the imbalance of trace elements within the OA knee joint microenvironment and demonstrated robust antioxidant capabilities and remarkable competitive properties for ubiquitin, thereby providing a novel therapeutic solution for OA treatment.

Toxic Metal Element Concentration in 31 Food Fishes from River Ganga: Risk Assessment on Human Consumption.

Consumption of toxic metal contaminated fish is a significant risk to human health. The Ganga river is one of the vital river systems in India, and it nurtures a rich biodiversity of flora and fauna. In the present study, screening of potential toxic metal elements (Cd, Cr, Mn, Cu, Pb, Ni, Zn, and As) was undertaken in 31 food fishes, especially the small indigenous fishes (SIFs) from the lower stretch of river Ganga by inductively coupled plasma mass spectrometry (ICP-MS). The concentration of toxic metal elements varied among different fish species. Among the toxic metal elements studied, Cr, Zn, and As were found to be dominant in Eleotris fusca; Cd, Ni, and Pb were highest in Securicula gora; Cu was highest in Cabdio morar; and Mn was highest in Coilia dussumieri. The average pollution load index values (APLI) for all the fishes analyzed were less than one except for Eleotris fusca, which indicated no serious toxic metal element pollution load. The estimated daily intake values (EDI) for the toxic metal elements were found to be within the permissible maximum tolerable daily intake (MTDI). Among the fishes studied, only a few species showed hazard index (HI) greater than one, indicating non-carcinogenic health risks. Similarly, the target carcinogenic values (TCR) for most of the toxic metal elements were below the permissible limit (10-4) in the fishes that assures minimal cancer risk. This study provides a comprehensive data on the composition of potential toxic metal elements of 31 food fishes from the lower stretch of the river Ganga, the first of its kind, and suggests the necessity of periodic monitoring of these in the aquatic ecosystem.

Effect of soil additives on biogeochemistry of ultramafic soils—an experimental approach with Brassica napus L

Ultramafic soils are characterized by low productivity due to the deficiency of macroelements and high content of Ni, Cr, and Co. Incorporation of ultramafic soils for agricultural and food production involves the use of fertilizers. Therefore, this study aims to find the soil additive that decreases the metallic elements uptake by plant using Brassica napus as an example. In this study, we evaluate the effect of manure (0.5 g N/kg of soil), humic acids (1 g of Rosahumus/1 dm3 H2O; 44% C), KNO3 (0.13 g K/kg of soil), lime (12.5 g/kg of soil), (NH4)2SO4 (0.15 g N/kg of soil), and Ca(H2PO4)2) (0.07 g P/kg of soil) on the phytoavailability of metallic elements. The effect of soil additives on metallic elements uptake by Brassica napus was studied in a pot experiment executed in triplicates. Statistical analysis was applied to compare the effects of additives in ultramafic soil on plant chemical composition relative to control unfertilized ultramafic soil (one-way ANOVA and Kruskal–Wallis test). The study shows that in almost all treatments, metallic elements content (Ni, Cr, Co, Al, Fe, Mn) is higher in roots compared to the aboveground parts of Brassica napus except for (NH4)2SO4, in which the mechanism of Mn accumulation is opposite. The main differences between the treatments are observed for the buffer properties of soil and the accumulation of specific metals by studied plants. The soils with the addition of lime and manure have the highest buffer properties in acidic conditions (4.9-fold and 2.1-fold increase relative to control soil, respectively), whereas the soil with (NH4)2SO4 has the lowest effect (0.8-fold decrease relative to control soil). Also, the addition of manure increases the biomass of aboveground parts of B. napus (3.4-fold increase) and decreases the accumulation of Ni (0.6-fold decrease) compared to plants cultivated in the control soil. On the contrary, the addition of (NH4)2SO4 noticeably increases the accumulation of Ni, Co, Mn, and Al in aboveground parts of B. napus (3.2-fold, 18.2-fold, 11.2-fold, and 1.6-fold, respectively) compared to plant grown in control soil, whereas the humic acids increase the accumulation of Cr in roots (1.6-fold increase). Therefore, this study shows that manure is a promising fertilizer in agricultural practices in ultramafic soil, whereas (NH4)2SO4 and humic acids must not be used in ultramafic areas.

Blood levels of metallic chemical element exposure patterns and associated factors in a population living in an Industrial District in Brazil

AIM:to estimate the level of metallic chemical elements in the population living in the Steel company vicinity in Santa Cruz, Rio de Janeiro, Brazil; and estimate the association between exposure to the Steel company and the blood metals concentrations patterns.METHOD:A cross-sectional study was carried out on 463 individuals aged 18+ years old residing 1+ years in the Steel company vicinity. Mg, Be, Co, Ba, Ni, Cd, Al, and Pb were assessed in blood by DRC-ICP-MS. Metallic chemical element concentration patterns were obtained by exploratory factor analysis in the studied population. Exposure was set as the distance (Km) from each participant's residence to the Steel company in Santa Cruz, georeferenced by GPS. The outcome was set as the positive factor loadings in the factor analysis, including Mg and Be (Factor-1), Co, Ba, and Ni (Factor-2), Cd, Al, and Pb (Factor-4). Crude and adjusted OR, and their respective 95 %CI, were estimated to explore associations between independent variables and the exposures to metallic elements positively associated with the factors using polychotomous logistic regression.RESULTS:A reduction of 19 % was found between each km distance from the residence and the Steel company and P50 concentration of Cd, Al, and Pb (ORP50=0.81; 95 %CI:0.67–0.97), after adjusting by age, sex, and smoking. No statistically significant associations were observed for the distance from residences and the Steel company, after adjusting for age, gender, having a domestic vegetable garden and chewing gum for Mg and Be concentrations (Factor-1) (ORP50=0.84; 95 %CI:0.70–1.01; ORP75=1.10; 95 %CI:0.91–1.34); nor for Co, Ba and Ni (Factor-2) blood concentrations(ORP50=1.10; 95 %CI:0.91–1.33; ORP75=1.03; 95 %CI:0.84–1.26), in the adjusted analysis.CONCLUSIONS: For each Km distance from residences to the Steel company, a 19 % reduction in the risk of Cd, Al, and Pb blood concentration was observed in the population living in Santa Cruz, Rio de Janeiro, Brazil.