185 results on '"SEMIMETALS"'
Search Results
2. Manipulation of topological spin textures in centrosymmetric rare-earth magnets.
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Zuo, Shulan, Qiao, Kaiming, Zhang, Ying, Zhao, Tongyun, Jiang, Chengbao, and Shen, Baogen
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SEMIMETALS ,TERBIUM ,TRANSMISSION electron microscopy ,MAGNETS ,MAGNETIC fields - Abstract
• Biskyrmions in Nd 1– x Tb x Co 5 alloy were directly observed and manipulated by in-situ LTEM. • Biskyrmions can spontaneously exist at room temperature in Nd 1– x Tb x Co 5 alloy. • A strategy to control biskyrmion nucleation via the in-plane magnetic field was proposed. • High-density biskyrmions were obtained by tuning the magnetic field. • Key factors for stabilizing spontaneous topological spin textures were revealed. Topologically protected magnetic skyrmions are expected to be used in the next-generation spintronic devices. Realizing their nucleation and manipulation at room temperature is fundamental for future practical applications. Here, using in situ Lorentz transmission electron microscopy and micromagnetic simulation, we demonstrate that magnetic biskyrmions can spontaneously exist at room temperature in Nd 1– x Tb x Co 5 (x = 0.3, 0.5) alloys. The spontaneous biskyrmions are controllably obtained over a wide temperature range across room temperature by switching atomic chemical environment. Furthermore, the density of biskyrmions can be tuned by a small magnetic field. High-density biskyrmions are stimulated to form in the thinner region at room temperature by introducing an in-plane magnetic field component. These results provide valuable insights into the manipulation of topological states, which is of great significance to their practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2023
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3. Effects of trace elements on mechanical properties of the TiZrHfNb high-entropy alloy.
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Yuan, Xiaoyuan, Wu, Yuan, Zhou, Meisa, Liu, Xiongjun, Wang, Hui, Jiang, Suihe, Zhang, Xiaobin, Wu, Honghui, Liu, Xiaochun, Chen, Zipan, Xu, Xiangqi, and Lu, Zhaoping
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TRACE elements ,YIELD stress ,RAW materials ,CRYSTAL grain boundaries ,BRITTLE fractures ,SEMIMETALS - Abstract
• In this work, we found that the mechanical properties of the tizrhfnb HEA greatly varied with the content of impurities in the samples even using high-purity raw materials. • The yield stress increment was mainly due to the strong interstitial strengthening effect of o contamination. Impurities of B, C, and si tend to segregate at GBs with zr and ti and form strong bonds of (Zr, Ti)-(B, C, Si) with large directionality. Different co-segregation degrees at GBs lead to the variation of ductility of the HEAs prepared with different batches of raw materials. • Our work suggests that metalloid impurities of B, C, and Si must be strictly controlled in refractory HEA. Refractory high-entropy alloys have great potential to be utilized as high-temperature materials, and the repeatability and reproducibility of their mechanical properties are critical for practical applications. In this work, nevertheless, we found that the mechanical properties of the TiZrHfNb HEA greatly varied with the content of impurities in the samples even using high-purity raw materials. Specifically, the oxygen impurity is mainly responsible for the increment of the yield stress due to the strong interstitial hardening effect, whilst the ductility deterioration closely associates with the content of metalloid elements B, C, and Si. Our analysis reveals that the metalloid elements not only tend to segregate at grain boundaries but also enhance the aggregation of Zr and Ti. Such co-segregation induced the formation of strong (Zr, Ti)-metalloid bonds, resulting in grain boundary embrittlement and brittle fracture. Our current work demonstrates that the impurity contents in refractory HEAs need to be strictly controlled during production in order to improve their stability of mechanical performance. [ABSTRACT FROM AUTHOR]
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- 2023
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4. Degradable magnesium-hydroxyapatite interpenetrating phase composites processed by current assisted metal infiltration in additive-manufactured porous preforms.
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Casas-Luna, Mariano, Montufar, Edgar B., Hort, Norbert, Díaz-de-la-Torre, Sebastian, Méndez-García, José Claudio, Vištejnová, Lucie, Brínek, Adam, Daňhel, Aleš, Dvořak, Karel, Kaiser, Jozef, and Čelko, Ladislav
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LIQUID metals ,METALS ,COMPACT bone ,COMPRESSIVE strength ,ELECTROLYTIC corrosion ,SEMIMETALS ,MAGNESIUM ,LIQUID alloys - Abstract
• Introduction of novel hydroxyapatite-magnesium interpenetrating phase composites. • Produced by ceramic additive manufacturing and liquid metal infiltration. • Magnesium provides mechanical strength in the range of cortical bone. • An osteoconductive hydroxyapatite scaffold is generated after magnesium degradation. • The structural and biological properties are controlled through the digital design. [Display omitted] This work explores ceramic additive manufacturing in combination with liquid metal infiltration for the production of degradable interpenetrating phase magnesium/hydroxyapatite (Mg/HA) composites. Material extrusion additive manufacturing was used to produce stoichiometric, and calcium deficient HA preforms with a well-controlled open pore network, allowing the customization of the topological relationship of the composite. Pure Mg and two different Mg alloys were used to infiltrate the preforms by means of an advanced liquid infiltration method inspired by spark plasma sintering, using a novel die design to avoid the structural collapse of the preform. Complete infiltration was achieved in 8 min, including the time for the Mg melting. The short processing time enabled to restrict the decomposition of HA due to the reducing capacity of liquid Mg. The pure Mg-base composites showed compressive yield strength above pure Mg in cast state. Mg alloy-based composites did not show higher strength than the bare alloys due to grain coarsening, but showed similar mechanical properties than other Mg/HA composites that have significantly higher fraction of metallic phase. The composites showed faster degradation rate under simulated body conditions than the bare metallic component due to the formation of galvanic pairs at microstructural level. Mg dissolved preferentially over HA leaving behind a scaffold after a prolonged degradation period. In turn, the fast production of soluble degradation products caused cell metabolic changes after 24 h of culture with not-diluted material extracts. The topological optimization and reduction of the degradation rate are the topics for future research. [ABSTRACT FROM AUTHOR]
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- 2022
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5. Evaluating washing techniques to eliminate external contamination of trace elements in bat fur and bird feathers.
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Keute, Jenna, Rizzo, Julia, Giunta, Flavia, and Hernout, Beatrice V.
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LEAD ,METAL analysis ,TRACE analysis ,TRACE elements ,SEMIMETALS ,TRACE metals - Abstract
Non-invasive proxies, such as fur and feathers, are likely to be increasingly used to assess the potential exposure of chemicals, including trace metals and metalloids. However, the amount of external contamination is usually unknown, and there is no standard method for removing external contamination of trace metals in fur or feathers. To date, 40 % of studies published related to the measurement of trace metal levels in fur or the hair of non-human mammals and 24 % of studies in feathers do not state any washing methods or did not wash the samples before analysis. We assessed three washing techniques to remove external contamination of arsenic (As), lead (Pb), and zinc (Zn) from bat fur. We selected the three most frequently used fur washing methods from literature. To test these methods, fur samples from great flying foxes (Pteropus neohibernicus neohibernicus , n=15 individuals) from Papua New Guinea preserved over eight decades (AMNH, USA) were used. Percentages of trace metal removed are 87.19 % (SD= 12.28), 92.99 % (SD= 5.5) and 88.57 % (SD= 9.33) for As, 54.72 % (SD= 31.64), 55.89 % (SD= 37.87), and 53.93 % (SD= 41.28) for Pb, and 74.03 % (SD= 22.96), 22.93 % (SD= 73), and 24.95 % (SD= 49.5) for Zn using M2, M3, and M4, respectively. We also assessed four washing techniques to remove external contamination of arsenic (As), mercury (Hg), and zinc (Zn) from bird feathers. We identified the four most prevalent washing techniques in the literature used for feathers. We used feathers from the great horned owl (Bubo virginianus) and the great blue heron (Ardea herodias) to test these methods. Percentages of trace metal removed are 34.35 % (SD= 44.22), 69.22 % (SD= 36.5), 62.59 % (SD= 48.37), and 80.89 % (SD= 14.54) for As, 66.97 % (SD= 13.26), 29.4 % (SD= 67.06), 49.68 % (SD= 42.33), and 28.88 % (SD= 69) for Hg, and <0 % (SD= 80.1), 0 % (SD= 29.55), 11.23 % (SD= 47.73), and 57.09 % (SD= 21.2) for Zn using M2, M3, M4, and M5, respectively. This study shows the importance of washing fur and feather samples prior to trace metals analyses in ecotoxicology and biomonitoring studies. • External contamination overestimates metal levels without prior washing • Acetone and detergent are the most effective reagents • Washing reagents on these matrices prior to metal analyses is metal specific • No washing procedure has yet ensured total removal of exogenous contamination [ABSTRACT FROM AUTHOR]
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- 2024
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6. Transition metal borides of Ni-B (Co-B) as alternative non-precious catalytic materials: Advances, potentials, and challenges. Short review.
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Lewandowski, Marek, Bartoszewicz, Maria, Jaroszewska, Karolina, and Djéga-Mariadassou, Gérald
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PRECIOUS metals ,BORIDES ,AMORPHOUS alloys ,METALLIC glasses ,SEMIMETALS ,ENVIRONMENTAL remediation ,TRANSITION metals - Abstract
[Display omitted] This review gives a brief presentation of the types, structure, synthesis, and application of amorphous transition metal borides (Mt-B) in particular the bulk or supported nickel and cobalt borides (NiB and CoB). Mt-B materials are amorphous metal-metalloid alloys and constitute an important group of catalytic systems due to their special chemical and physical properties, including broad composition, structural homogeneity, and high concentration of coordination unsaturated sites. These features along with the relatively cheap and simple methods of synthesis make them interesting alternative catalytic materials for numerous new, cost-effective, and environmentally sustainable yields and applications. Much attention has been paid to Mt-B as an interesting alternative to the industrially applied catalysts based on expensive and/or susceptible to sulphur poisoning, precious metals, and Raney nickel. Therefore, this review presents the application of Mt-B in different sectors: chemical production, energy storage/conversion, and environmental remediation. The current and future directions of research in this area are analysed. [ABSTRACT FROM AUTHOR]
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- 2022
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7. Associations between seminal plasma metals/metalloids and semen quality: A cross-sectional study.
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Wen, Juan, Yao, Xiaodie, Lu, Renjie, Geng, Shijie, Wang, Junya, Zhou, Jing, Li, Ying, and Hu, Lingmin
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SEMEN analysis ,SEMEN ,METALS ,CROSS-sectional method ,SEMIMETALS ,SPERM count ,LOGISTIC regression analysis - Abstract
Exposure to metals/metalloids is reported to potentially influence semen quality. While most studies have focused on single metal impacts, the link between exposure to multiple metals and semen quality has remained less explored. The study aimed to investigate the effects of both individual and mixed metal/metalloid exposure on semen quality. A total of 330 men were recruited from three reproductive centers in eastern China. Seminal plasma levels of 25 metals/metalloids and sperm parameters were determined. We used the Generalized Linear Model (GLM) and Restricted Cubic Spline (RCS) to assess the relationships between single metals/metalloids and semen quality. The weighted quantile sum (WQS) models were then applied to evaluate the combined effect of all these metals/metalloids. We observed positive associations of exposure to lithium (Li), zinc (Zn), and magnesium (Mg) with an increased risk of below reference values for progressive motility and total motility using a logistic regression model (P < 0.05). Additionally, our results also revealed a significant inverse relationship between aluminum (Al) and both sperm concentration and count, while cobalt (Co) demonstrated a positive association with sperm concentration (P < 0.05). Notably, the WQS model indicated a significant positive association between exposure to metal/metalloid mixtures and the risk of abnormal progressive motility (OR: 1.57; 95%CI: 1.10, 2.24) and abnormal total motility (OR: 1.53; 95%CI: 1.06, 2.19), with this association primarily driven by Li, Mg, and Zn. In summary, our findings indicate that exposure to metal/metalloid mixtures might have an adverse effect on semen quality. • Levels of 25 metals/metalloids were measured in the seminal plasma of 330 men. • Increased levels of Li, Zn, Mg and Al were correlated with diminished semen quality. • Exposure to metal/metalloid mixtures may have an adverse effect on semen quality. • Li, Mg, and Zn have been identified as the main contributors to the mixing effect. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Health risk assessment of heavy metal toxicity in the aquatic environment of the Persian Gulf.
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Taghavi, Mahmoud, Shadboorestan, Amir, Kalankesh, Laleh R., Mohammadi-Bardbori, Afshin, Ghaffari, Hamid Reza, Safa, Omid, Farshidfar, Gholamreza, and Omidi, Mahmoud
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HEAVY metals ,HEAVY metal toxicology ,HEALTH risk assessment ,TUNA ,DISEASE risk factors ,SEMIMETALS - Abstract
This study aims to explore the potential health risks linked to four heavy metals/metalloids (Pb, Cd, As, Hg) present in four commercially important fish species (Scombromorus commerson, Pseudorhombus elevatus, Thunnus tonggol and Otolithes ruber) in the Persian Gulf. Metals in fish muscle tissue were analyzed via ICP-MS. The analysis revealed that Scombromorus commerson (except for Pb) and Thunnus tonggol (except for As) exhibited the highest and lowest contamination levels, respectively. The Hazard Index findings highlighted arsenic and mercury as the most hazardous elements. However, the Target Hazard Quotient values for each metal and fish species remained within safe thresholds. The highest and lowest Total Carcinogenic Risk was concerning Pseudorhombus elevates (As: 7.41-E05), and Thunnus thonggol (Pb: 3.21-E07), respectively. TCR analysis suggests that the cancer risk of studied metals was below the negligible level (TCR < 10
−6 ) or within the acceptable level (10−6 < TCR < 10−4 ), potentially not posing carcinogenic risks through extended consumption. [Display omitted] • Pb and Hg exhibit the highest concentrations in the tissues of the species. • Pseudorhombus elevatus had the highest concentration of heavy metals (except for Pb). • Thunnus thonggol had the lowest concentration of heavy metals (except for As). • The highest and lowest TCR: Pseudorhombus elevatus (As: 7.41-E05), and Thunnus thonggol (Pb: 3.21-E07). [ABSTRACT FROM AUTHOR]- Published
- 2024
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9. Human health risk assessment associated with the reuse of treated wastewater in arid areas.
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Shomar, Basem and Rovira, Joaquim
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HEALTH risk assessment ,POLLUTANTS ,SEWAGE ,SEWAGE disposal plants ,SALINE water conversion ,ANTIBIOTIC residues ,SEMIMETALS - Abstract
Qatar produces more than 850,000 m
3 /day of highly treated wastewater. The present study aims at characterizing the effluents coming out of three central wastewater treatment plants (WWTPs) of chemical pollutants including metals, metalloids and antibiotics commonly used in the country. Additionally, the study is assessing human health risks associated with the exposure to the treated wastewater (TWW) via dermal and ingestion routes. Although the origin of domestic wastewater is desalinated water (the only source of fresh water), the results show that the targeted parameters in TWW were within the international standards. Concentrations of Cl, F, Br, NO 3 , NO 2 , SO 4 and PO 4 , were 389, <0.1, 1.2, 25, <0.1, 346, and 2.8 mg/L, respectively. On the other hand, among all cations, metals and metalloids, only boron (B) was 2.1 mg/L which is higher than the Qatari guidelines for TWW reuse in irrigation of 1.5 mg/L. Additionally, strontium (Sr) and thallium (Tl) were detected with relatively high concentrations of 30 mg/L and 12.5 μg/L, respectively, due to their natural and anthropogenic sources. The study found that the low concentrations of all tested metals and metalloids do not pose any risk to human health. However, Tl presents exposure levels above the 10 % of oral reference dose (HQ = 0.4) for accidental oral ingestion of TWW. The results for antibiotics show that exposure for adults and children to TWW are far below the admissible daily intakes set using minimum therapeutic dose and considering uncertainty factors. Treated wastewater of Qatar can be used safely for irrigation. However, further investigations are still needed to assess microbiological quality. [Display omitted] • Three central wastewater plants in Qatar own the highest treatment technologies. • Metals, metalloids and antibiotics concentrations in the effluents are minimum. • Dermal and ingestion exposure routes used for health risks in adults and children. • No health risks (HQ < 1) were found due to exposure to metals and antibiotics. • Treated wastewater in Qatar can be used safely for irrigation. [ABSTRACT FROM AUTHOR]- Published
- 2024
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10. Metal and metalloid maternal transfer in a newborn West Indian manatee (Trichechus manatus) two years after the northeastern oil spill disaster of 2019 in Brazil.
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Lemos, Leila S., Attademo, Fernanda L.N., de Paiva, Lauro Henrique, Costa, Alexandra F., Reis, Laura M.A., de Oliveira Luna, Fábia, Hauser-Davis, Rachel Ann, and Siciliano, Salvatore
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OIL spills ,MANATEES ,INDIGENOUS peoples of South America ,SEMIMETALS ,LEAD ,NEWBORN infants - Abstract
A large-scale oil spill along the northeastern Brazilian coast in 2019–2020 severely impacted primary manatee habitats in Brazil. This study aimed to assess metal and metalloid contamination in a dead manatee calf found following this oil spill. Several elements were detected, including chromium, iron, nickel, lead, and vanadium, which are crude oil components, and thallium, a component of dispersants used to degrade and dissipate crude oil. The presence of these contaminants in the manatee calf is indicative of maternal exposure, metabolism, and newborn transference via placenta and lactation. This is the first report of mother-calf metal transfer in manatees, highlighting the species' vulnerability and potential long-term population dynamics effects, and the first report for several metals and metalloids in these animals, laying the foundation for future research efforts. These findings highlight the urgent need for continued environmental monitoring, ecotoxicological assessments, and conservation initiatives. • The 2019 oil spill severely impacted manatee habitats along the Brazilian coast. • Several metals and metalloids were detected in an infant manatee after the oil spill. • Maternal exposure, metabolism, and newborn placental transference are probable. • This is the first study to report mother-calf metal transfer in manatees. • The findings raise concerns about potential long-term population effects. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Baseline metal and metalloid contamination in two marine sponge species, Hymeniacidon heliophila and Desmapsamma anchorata, from southeastern Brazil.
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Hauser-Davis, Rachel Ann, dos Santos, Leandro Ribeiro, Leite, João Victor Meirelles, de Almeida, Regina Fonsêca, de C. Maciel, Oswaldo Luiz, Pierre, Tatiana Dillenburg Saint, Meurer, Bruno Correa, and Pereira, Oliver Alexandre F.C.
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SEMIMETALS ,INDUCTIVELY coupled plasma mass spectrometry ,SPONGES (Invertebrates) ,ECOLOGICAL risk assessment ,METABOLIC detoxification ,COPPER - Abstract
Sponges are not routinely employed as metal bioindicators in Brazil. In this sense, this study reports baseline metal and metalloid concentrations, determined by inductively coupled plasma mass spectrometry, for two Demospongiae sponge species, Hymeniacidon heliophila and Desmapsamma anchorata , sampled from two Southeastern Brazil areas. Sponges from Ilha Grande Bay, an Environmental Protection Area, exhibited higher Al, As, Cd, Co, Cr, Fe, and Ni levels compared to Vermelha Beach, a metropolitan area in the Rio de Janeiro city. Several strong correlations were noted between elemental pairs, indicating common contamination sources and/or similar metabolic detoxification routes. Comparisons of the means determined herein for each study site to other reports indicate mostly lower Ag, As, Co, Cd, and Cu levels, while Al levels were higher than other studies, and Cr, Ni, and Fe were within reported ranges. These baseline data further knowledge on metal pollution in Desmspongiae members, which are still limited. [Display omitted] • Metals were determined in two marine sponges from Southeastern Brazil. • Most metals were higher in the species from an Environmental Protection Area. • Ag and Cu were higher in the species from metropolitan region of Rio de Janeiro. • Several strong correlations between metal pairs were observed. • These baseline data further knowledge on metal pollution in Demospongiae members. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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12. Metal and metalloid content, bioavailability and sorption processes in glitter and raw glitter materials and associations with human and ecological risk concerns.
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Meirelles, J.V., de Almeida, R.F., Morgado, A.J., de Castro, T.B., Rocha, R.C.C., Hauser-Davis, R.A., and Saint'Pierre, T.D.
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INDUCTIVELY coupled plasma mass spectrometry ,PLASTIC marine debris ,SEMIMETALS ,POLLUTANTS ,RAW materials ,EMERGING contaminants - Abstract
Microplastics comprise a significant group of emerging environmental contaminants with the capacity to adsorb several contaminants. These, in turn, undergo bioaccumulation and biomagnification processes throughout aquatic trophic chains. Glitter, a microplastic powder composed of a combination of polymers, and raw glitter materials were investigated herein concerning metal and metalloid content, bioavailability, and sorption processes by inductively coupled plasma mass spectrometry (ICP-MS). Metal and metalloid concentrations were higher in glitter than in raw glitter materials, but all were below the limits established by the Brazilian National Health Surveillance Agency. Elements present in glitter originate mainly from pigments and, thus, depend on glitter color. The bioavailability of the determined elements concerning human skin was assessed. Low desorbed concentrations in solution indicate that glitter does not represent a health risk through dermal contact concerning metal and metalloid contamination. However, several elements were shown to undergo significant desorption and adsorption processes. The findings reported herein indicate seemingly low human health risks from dermal glitter contact but reinforce glitter risks as aquatic environment metal and metalloid transport vectors. • Elemental contents were higher in glitter than in raw glitter materials but below Brazilian limits. • Elements in glitter originate mostly from pigments, and, thus, depend on glitter color. • Low desorbed concentrations suggest that glitter does not represent a dermal contact health risk. • Significant desorption and adsorption processes were noted for several elements. • Glitter risks as elemental transport vectors in aquatic environments are noted. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Additive manufacturing of high-entropy alloys by thermophysical calculations and in situ alloying.
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Cagirici, Mehmet, Wang, Pan, Ng, Fern Lan, Nai, Mui Ling Sharon, Ding, Jun, and Wei, Jun
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ELECTRON beam furnaces ,ALLOYS ,NICKEL-chromium alloys ,SEMIMETALS - Abstract
• In-situ alloying shortens the development circle of new high entropy alloys (HEAs) via electron beam melting (EBM). • EBM is a promising technology to fabricate high quality CoCrFeNiMn- x Ti HEAs. • Ti addition in CoCrFeNiMn HEA promotes the formation of σ, Cr-rich γ and Ni rich D0 24 phases. • Significant improvement in the micro-hardness of CoCrFeNiMn- x Ti HEAs is achieved. Electron beam melting (EBM) is a promising technology to manufacture various alloys with outstanding properties; however, the number of available alloys is limited. We propose in situ alloying to accelerate the development of advanced and novel alloys, based on thermophysical calculations and CALPHAD approach, during the EBM process. We demonstrate our concept through the design and fabrication of high entropy alloys (HEAs). Three CoCrFeNiMn- x Ti (x =0.18, 0.50, 2.00, in molar %) HEAs are manufactured. EBM-built HEAs achieve a homogeneous distribution of elements while forming multiphase alloys resulted from the hot powder bed. The topological structures formed by secondary phases contribute to an increase in the hardness of EBM-built HEAs up to 900 HV1. Considering alloy design, a systematic analysis on CoCrFeNiMn-0.18Ti HEA elucidates the microstructural evolution in detail. These findings provide a deep understanding of in situ alloying and pave the way to develop new alloys specific to the EBM process. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2021
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14. Balancing benefits of strength, plasticity and glass-forming ability in Co-based metallic glasses.
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Zhao, Yimeng, Li, Xuan, Liu, Xiaobin, Bi, Jiazi, Wu, Yang, Xiao, Ruijuan, Li, Ran, and Zhang, Tao
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METALLIC glasses ,STRENGTH of materials ,MATERIAL plasticity ,SEMIMETALS ,BEHAVIORAL assessment ,ABILITY - Abstract
[Display omitted] • A family of novel Co-Ta-B-Si bulk metallic glasses (BMGs) was developed. • The BMGs exhibit both high strength above 5.5 GPa and large plasticity up to 6.4 %. • The BMGs show the enhancement of glass-forming ability (GFA: up to 4 mm). • The improvement of plasticity and GFA were explained by calculated analysis. • A self-organization behavior of shear bands is liable for the increase in plastic. Development of advanced metals materials with ultrahigh strength, large plasticity and high thermostability is one of the most attractive aims for materials researchers. Co-based bulk metallic glasses (BMGs) with the highest strength (up to 6 GPa) and special strength (up to 650 Nm/g) among all of metals materials so far we known have received extensive attentions. In this paper, a family of Co-Ta-B-Si BMGs with high glass-transition temperature (above 870 K), large compressive plasticity (up to 6.4 %) and high strength (above 5.5 GPa), and high glass-forming ability (the critical diameter, D c : up to 4 mm) was developed by accurately tuning metalloid element contents of Si and B in the parental alloy of Co 55 Ta 10 B 35. The changes of glass formation and plasticity caused by the adjustment of the constituent metalloid elements were evaluated by the combination of experimental and calculated results. The reason for the significant improvement of plastic deformation is revealed by the analysis of the self-organization behaviors of high-density shear bands. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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15. Phytoremediation Potential of Iris spp.
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CRIŞAN, Ioana, VIDICAN, Roxana, PLEŞA, Anca, and MIHĂIESCU, Tania
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PHYTOREMEDIATION ,HEAVY metals ,SEMIMETALS ,IRISES (Plants) ,WASTEWATER treatment ,VALUE chains ,GREEN technology ,HEAVY metal toxicology - Abstract
Iris plants are widely cultivated flowering ornamentals, with a long history of traditional use in Eurasia, where this genus is reaching the highest diversity. This paper aims to provide an overview on recent advances related to the phytoremediation potential of plants from the genus Iris, in order to promote the use of these species in phytoremediation programs. According to the relevant literature, eight species from genus Iris present phytoremediation potential (I. dichotoma, I. germanica, I. halophila, I. lactea, I. latifolia, I. pseudacorus, I. sibirica, I. wilsonii). The studies addressed potential of plants to mitigate toxic metals/metalloids (As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Zn), excess of nutrients (P, N), pesticides, petroleum hydrocarbons, pharmaceuticals as well as dyes. Most studies focused on wastewater treatment and environments contaminated due to mining activities. Main hindrances in upscaling this green technology remain mitigation of toxicity stress in plants during remediation and the disposal of resulting contaminated biomass. In this sense, use of beneficial microorganisms to alleviate phytotoxicity effects and new valorization possibilities of contaminated Iris spp. biomass have been proposed recently. Designing an entire cycle that includes phytoremediation and sustainable value chains for contaminated biomass could prove feasible and should receive more attention. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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16. Tunable quantum Shubnikov-de Hass oscillations in antiferromagnetic topological semimetal Mn-doped Cd3As2.
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Guo, Jie, Zhao, Xinguo, Sun, Naikun, Xiao, Xiaofei, Liu, Wei, and Zhang, Zhidong
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SEMIMETALS ,OSCILLATIONS ,FERMI energy ,GEOMETRIC quantum phases ,ANTIFERROMAGNETIC materials ,FERMI level ,SURFACE states ,ANTIFERROMAGNETISM - Abstract
Three-dimensional Dirac semimetal Cd 3 As 2 has been considered as an excellent candidate for applications of electronic devices owing to its ultrahigh mobility and air-stability. However, current researches are focused mainly on the use of gate-voltage to control its carrier transport tunability, while the manipulation of transport properties by element-doping is quite limited. Here we report the tunable magneto-transport properties by adjusting Mn-doping in the Cd 3 As 2 compound. We find that Mn-element doping has a strong influence on the Fermi level positions, and the Fermi energy approaches to Dirac point with higher Mn-doping. More importantly, the introduction of Mn atoms transforms diamagnetic Cd 3 As 2 to antiferromagnetic (Cd, Mn) 3 As 2 , which provides an approach to control topological protected Dirac materials by manipulating antiferromagnetic order parameters. The Shubnikov-de Hass oscillation originates from the surface states, and the Landau fan diagram yields a nontrivial Berry phase, indicating the existence of massless Dirac fermions in the (Cd 1- x Mn x) 3 As 2 compounds. Our present results may pave a way for further investigating antiferromagnetic topological Dirac semimetal and expand the potential applications in optoelectronics and spintronics. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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17. Serum copper profile in patients with type 1 diabetes in comparison to other metals.
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Squitti, Rosanna, Negrouk, Valentine, Perera, Marisa, Llabre, Maria M., Ricordi, Camillo, Rongioletti, Mauro Ciro Antonio, and Mendez, Armando J.
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TYPE 1 diabetes ,SEMIMETALS ,INDUCTIVELY coupled plasma mass spectrometry ,PANCREATIC beta cells ,METALS - Abstract
Type 1 diabetes (T1D) is a chronic condition in which the pancreas loses the ability to produce insulin due to an autoimmune destruction of the insulin producing beta cells in the pancreatic islets of Langerhans. Pathophysiological complications related to diabetes include micro and macrovascular disease, nephropathy, and neuropathy that can also be affected by environmental factors such as lifestyle and diet. The current study aimed to evaluate the serum levels of total copper, the copper-carrying protein, ceruloplasmin and nonceruloplasmin bound copper (nonceruloplasmin-Cu) and other essential and environmental metals and metalloids in subjects with T1D compared with healthy controls. A cohort of 63 subjects with T1D attending Diabetes Clinics at the University of Miami and 65 healthy control subjects was studied. Metals and metalloids were measured by inductively coupled plasma mass spectrometry. A main finding of this study was that total copper and ceruloplasmin levels were higher in persons with T1D compared to healthy controls. In comparison to other metals and clinical variables, elevated copper was the strongest factor associated with T1D resulting in a15-fold increased odds of having the disease per standard deviation increase. Our results suggest a metal and metalloid perturbation in T1D with a significant involvement of Copper dysfunction in the disease pathology, possibly linked to inflammatory processes. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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18. Geographical distribution of metals and metalloids along the estuary of the Oka River in the biosphere reserve of Urdaibai, Spain.
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Alberdi Igartua, X., Rodriguez-Iruretagoiena, A., Gredilla, A., Fdez-Ortiz de Vallejuelo, S., Arana, G., de Diego, A., and Madariaga, J.M.
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BIOSPHERE reserves ,ESTUARIES ,SEMIMETALS ,METALS ,INDUSTRIAL wastes ,COPPER ,SEDIMENT sampling - Abstract
Sediments sampled at the estuary of the Oka River in the biosphere reserve of Urdaibai, Spain were analyzed for trace elements. Sediments were collected at 45 points of the estuary and the concentration of 14 elements was measured. The geoaccumulation indexes (I geo), Normalized Average Weighted Concentrations (NAWC) and mean Effect Range-Median quotients (mERMq) were calculated. The results obtained were complementary and allowed intra- and inter-estuary comparison. According to the present findings, the estuary was classified as healthy, since the anthropogenic contribution of metals and metalloids was generally small. However, shipping and fishing activities at the ports of Bermeo and Mundaka and urban and industrial wastes from Gernika were regarded as the major pollution sources. Nevertheless, only slightly contaminated and toxic sediments, especially related to Ni and Cu, were found in the towns of Gernika and Mundaka. • The anthropogenic metal presence along the Oka estuary was generally low. • Shipping and fishing activities at the ports were the main contamination sources. • Sediments near the main towns presented slightly contamination and toxicity. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Multifaceted roles of silicon nano particles in heavy metals-stressed plants.
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Asgher, Mohd, Rehaman, Abdul, Nazar ul Islam, Syed, and Khan, Nafees A.
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HEAVY metal toxicology ,HEAVY metals ,ABIOTIC stress ,ESSENTIAL nutrients ,SILICON ,PLANT maintenance ,SEMIMETALS - Abstract
Heavy metal (HM) contamination has emerged as one of the most damaging abiotic stress factors due to their prominent release into the environment through industrialization and urbanization worldwide. The increase in HMs concentration in soil and the environment has invited attention of researchers/environmentalists to minimize its' impact by practicing different techniques such as application of phytohormones, gaseous molecules, metalloids, and essential nutrients etc. Silicon (Si) although not considered as the essential nutrient, has received more attention in the last few decades due to its involvement in the amelioration of wide range of abiotic stress factors. Silicon is the second most abundant element after oxygen on earth, but is relatively lesser available for plants as it is taken up in the form of mono-silicic acid, Si(OH) 4. The scattered information on the influence of Si on plant development and abiotic stress adaptation has been published. Moreover, the use of nanoparticles for maintenance of plant functions under limited environmental conditions has gained momentum. The current review, therefore, summarizes the updated information on Si nanoparticles (SiNPs) synthesis, characterization, uptake and transport mechanism, and their effect on plant growth and development, physiological and biochemical processes and molecular mechanisms. The regulatory connect between SiNPs and phytohormones signaling in counteracting the negative impacts of HMs stress has also been discussed. [Display omitted] • SiNPs enhance growth and development of heavy metal-stressed plants. • SiNPs act as protective shield against heavy metal toxicity. • SiNPs promote the detoxification of heavy metals. • SiNPs modulate gene expression and signaling pathways/phytohormones. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Associations between plasma metal/metalloid mixtures and the risk of central obesity: A prospective cohort study of Chinese adults.
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Zhang, Zirui, Xiao, Yang, Long, Pinpin, Yu, Yanqiu, Liu, Yiyi, Liu, Kang, Yang, Handong, Li, Xiulou, He, Meian, Wu, Tangchun, and Yuan, Yu
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SEMIMETALS ,OBESITY ,COHORT analysis ,LONGITUDINAL method ,METALS - Abstract
Central obesity has increased rapidly over the past decade and posed a substantial disease burden worldwide. Exposure to metals/metalloids has been acknowledged to be involved in the development of central obesity through regulation of cortisol, insulin resistance, and glucocorticoid receptor reduction. Despite the importance, it is lack of prospective study which comprehensively evaluate the relations between multiple metals exposure and central obesity. We explored the prospective associations of plasma metal concentrations with central obesity in a prospective study of the Dongfeng-Tongji cohort. The present study included 2127 participants with a 6.87-year mean follow-up duration. We measured 23 plasma metal/metalloid concentrations at baseline. The associations between metals and incident central obesity were examined utilizing the Cox proportional hazard regression in single and multiple metals models. Additionally, we applied elastic net (ENET), Bayesian kernel machine regression (BKMR), plasma metal score (PMS), and quantile-based g-computation (Qgcomp) models to explore the joint associations of metal mixtures with central obesity. After adjusting potential confounders, we found significant associations of plasma manganese (Mn) and thallium (Tl) concentrations with a higher risk of central obesity, whereas plasma rubidium (Rb) concentration was associated with a lower risk of central obesity both in single and multiple metals models (all FDR <0.05). The ENET and Qqcomp models verified similar metals (Mn, Rb, and Tl) as important predictors for central obesity. The results of both BKMR model and PMS suggested cumulative exposure to metal mixtures was associated with a higher risk of central obesity. Our findings suggested that co-exposure to metals was associated with a higher risk of central obesity. This study expands our knowledge that the management of metals/metalloids exposure may be beneficial for the prevention of new-onset central obesity, which may subsequently alleviate the disease burden of late-life health outcomes. [Display omitted] • We explored the joint association of plasma metals with incident central obesity. • We applied multipollutant-based statistical methods to investigate the association. • Plasma manganese and thallium were positively related to incident central obesity. • Plasma rubidium was inversely related to a risk of incident central obesity. [ABSTRACT FROM AUTHOR]
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- 2024
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21. New para-magnetic (CoFeNi)50(CrMo)50-x(CB)x (x = 20, 25, 30) non-equiatomic high entropy metallic glasses with wide supercooled liquid region and excellent mechanical properties.
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Kim, Jeong Tae, Hong, Sung Hwan, Park, Jin Man, Eckert, Jürgen, and Kim, Ki Buem
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SUPERCOOLED liquids ,METALLIC glasses ,TRANSITION metals ,ALLOYS ,CARBON-black ,SEMIMETALS ,ENTROPY ,ELASTIC modulus - Abstract
In this study, high entropy metallic glasses (HEMGs) were developed through a combination of concepts for designing metallic glasses (main element + transition metal + metalloid element) and high-entropy alloys (more than five elements, each element having an atomic concentration between 5 at.% and 35 at.%). The developed metallic glass alloys are composed of Co-Fe-Ni main elements, transition metals (Cr, Mo) and metalloid elements (C, B). Moreover, the present work reports the thermal, mechanical and magnetic properties of (CoFeNi) 50 (CrMo) 50- x (CB) x alloys with x = 20, 25, 30. The developed as-spun HEMGs exhibit typical paramagnetic properties even for a high amount of ferromagnetic elements (Co, Fe, and Ni) and have high elastic modulus (103–160 GPa) and hardness (14–27 GPa), thus possessing mechanical properties similar to well-known Co-based metallic glasses (Co-Cr-Mo-C-B system). In addition, some of the bulk samples prepared with a diameter of 2 mm form bulk metallic glasses with a high compressive strength around 3.5 GPa. The mechanisms determining the stability of the supercooled liquid, as well as the paramagnetic and mechanical properties for the developed non-equiatomic HEMGs, are discussed. [ABSTRACT FROM AUTHOR]
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- 2020
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22. Wing membrane and fur samples as reliable biological matrices to measure bioaccumulation of metals and metalloids in bats.
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Mina, Rúben, Alves, Joana, Alves da Silva, António, Natal-da-Luz, Tiago, Cabral, João A., Barros, Paulo, Topping, Christopher J., and Sousa, José Paulo
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SEMIMETALS ,SELENIUM ,METALS ,BIOACCUMULATION ,FUR ,BATS ,POLLUTANTS - Abstract
There is a growing conservation concern about the possible consequences of environmental contamination in the health of bat communities. Most studies on the effects of contaminants in bats have been focused on organic contaminants, and the consequences of bat exposure to metals and metalloids remain largely unknown. The aim of this study was to evaluate the suitability of external biological matrices (fur and wing membrane) for the assessment of exposure and bioaccumulation of metals in bats. The concentration of arsenic, cadmium, cobalt, chromium, copper, manganese, nickel, lead, selenium and zinc was measured in internal organs (liver, heart, brain), internal (bone) and external tissues (wing membrane, fur) collected from bat carcasses of four species (Hypsugo savii , Nyctalus leisleri , Pipistrellus pipistrellus , Pipistrellus pygmaeus) obtained in windfarm mortality searches. With the exception of zinc (P = 0.223), the results showed significant differences between the concentrations of metals in the analyzed tissues for all metals (P < 0.05). Significant differences were also found between organs/tissues (P < 0.001), metals (P < 0.001) and a significant interaction between organs/tissues and metals was found (P < 0.001). Despite these results, the patterns in terms of metal accumulation were similar for all samples. Depending on the metal, the organ/tissue that showed the highest concentrations varied, but fur and wing had the highest concentrations for most metals. The variability obtained in terms of metal concentrations in different tissues highlights the need to define standardized methods capable of being applied in monitoring bat populations worldwide. The results indicate that wing membrane and fur, biological matrices that may be collected from living bats, yield reliable results and may be useful for studies on bats ecotoxicology, coupled to a standardized protocol for large-scale investigation of metal accumulation. Image 1 • Internal and external samples were used to assess metal accumulation in bats. • Metal concentrations measured depended on the tissue/organ analyzed. • Wing membrane and fur had the highest metal concentrations for most metals. • Wing membrane can be a proxy for metal concentrations in internal organs. • External biological matrices are the best option for studies on wildlife ecotoxicology. Wing membrane and fur are reliable biological matrices for studies on bats ecotoxicology, being useful to measure bat's exposure to metals/metalloids. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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23. JOINT DIAMONDS AND LAVER DIAMONDS.
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HABIČ, MIHA E.
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LARGE cardinals (Mathematics) ,SEMIMETALS - Abstract
The concept of jointness for guessing principles, specifically ${\diamondsuit _\kappa }$ and various Laver diamonds, is introduced. A family of guessing sequences is joint if the elements of any given sequence of targets may be simultaneously guessed by the members of the family. While equivalent in the case of ${\diamondsuit _\kappa }$ , joint Laver diamonds are nontrivial new objects. We give equiconsistency results for most of the large cardinals under consideration and prove sharp separations between joint Laver diamonds of different lengths in the case of θ -supercompact cardinals. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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24. Long term monitoring of metal pollution in sediments as a tool to investigate the effects of engineering works in estuaries. A case study, the Nerbioi-Ibaizabal estuary (Bilbao, Basque Country).
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Garmendia, Marina, Fdez-Ortiz de Vallejuelo, Silvia, Liñero, Olaia, Gredilla, Ainara, Arana, Gorka, Soto, Manuel, and de Diego, Alberto
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POLLUTION monitoring ,ESTUARIES ,SEMIMETALS ,HOT spots (Pollution) ,HEAVY metals ,SEDIMENTS ,TUNNEL design & construction - Abstract
The Nerbioi-Ibaizabal estuary (Bilbao, Basque Country) suffered an important input of contaminants, including metals and metalloids, between 1875 and 1975. We collected sediments in the tidal part of the river in January 2018 and measured the concentrations of 27 elements in them. At that time, two important construction works were taking place in the area: the extension of the commercial port and the opening of long semi-closed channel. Comparing the current metallic hotspots with the geographical distribution of elements in previous years (2009, 2010 and 2014) showed us that these works seem to have significantly influenced the distribution of toxic elements in the estuary, even if the critical point of the second one is still to arrive with the inundation of the connection to the mainland. Long term pollution monitoring reveals as a powerful tool to check the effects of ongoing engineering works in estuarine environments. • Hotspots of toxic elements (As, Cd, Hg, Mn, Pb and Zn) were identified in the estuary. • A few sediments were catalogued as moderately toxic, due to high content of Pb and Zn. • Sources of toxic metals and metalloids to the estuary were identified. • Engineering works currently in progress influence metal distribution in the estuary. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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25. Effect of Foliar Applied Nitrogen to Cotton with Artificial Terminal and Node Removal.
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Plumblee, Michael T., Dodds, Darrin M., Krutz, L. Jason, Catchot, Angus L., Irby, J. Trenton, and Jenkins, Johnie N.
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COTTON quality ,COTTON picking ,COTTON ,COTTON fibers ,CHEMICAL oxygen demand ,NITROGEN ,SEMIMETALS - Abstract
Management decisions are needed for producers who experience hail or wildlife damage to cotton when replanting is not an option. This research was conducted to determine if applications of foliar nitrogen (N) fertilizer had an effect on cotton growth, lint yield, lint turnout, or fiber quality to cotton that had eight nodes of growth, including the apical meristem, removed at pinhead square or first bloom. The effects of foliar N (no foliar N, foliar N applied at the time of damage, one week after damage, two weeks after damage, at the time of damage + one week after damage, at the time of damage + two weeks after damage, one week after + two weeks after damage, and at the time of damage + one week after + two weeks after damage) were evaluated on Phytogen 499 WRF planted in Mississippi in 2016 and 2017. The interaction of foliar N application timing and the time damage occurred did not affect cotton height at harvest, lint turnout, lint yield, or fiber quality. Cotton growth stage when damage occurred affected cotton height at harvest, lint turnout, lint yield, micronaire, strength, and fiber elongation. Timing of foliar N affected lint turnout, micronaire, and fiber strength. No differences in lint yield were observed following any foliar N application timing; however, a 28 to 37% lint yield reduction was observed in damaged cotton compared to the untreated. These data indicate that application of foliar N to damaged cotton did not increase cotton height, lint yield, lint turnout, or fiber quality compared to undamaged cotton; therefore, use of foliar N to bolster growth and yield of damaged cotton is not recommended. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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26. Transfer and biological effects of arsenate from soil through a plant-aphid system to the parasitoid wasp, Aphidius colemani.
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Kim, Myeongseob, Lee, Minyoung, Kim, Yongeun, Lee, Yun-Sik, Son, Jino, Hyun, Seunghun, and Cho, Kijong
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ARSENATES ,BIOACCUMULATION ,SEMIMETALS ,GREEN peach aphid ,SOIL pollution - Abstract
Abstract The accumulation of metalloid elements during transfer from contaminated soil to higher trophic levels may potentially result in the exposure of parasitic arthropods to toxic concentrations of these elements. This study examined the transfer of arsenate (As(V)) to aphids (Myzus persicae) from pepper plants cultivated in As(V) contaminated soils of two concentrations (2 and 6 mg As(V)/kg dry soil), and the subsequent biological effects on the aphid parasitoid, Aphidius colemani. Results showed that considerable quantities of As(V) were transferred to the plant in a concentration-dependent manner and were partitioned in the plant parts in the order of roots > stems > leaves. The accumulation of As(V) in the aphids increased with the concentrations in the plants; however, the transfer coefficient of As(V) from leaf to aphid was relatively similar and constant (0.07–0.08) at both soil As(V) concentration levels. Increased levels of As(V) significantly affected fecundity and honeydew production in aphids, but survival and developmental time were unaffected. Fecundity (mummification rate) of the parasitoid was not impaired by host As(V) contamination; however, vitality (eclosion rate) was significantly affected. Results are discussed in relation to possible ecological risks posed by the transfer of soil As(V) via the plant-arthropod system to parasitoid arthropods in agroecosystems. Highlights • This study examined the transfer of arsenate (As(V)) in soil via a food chain. • Plants could uptake and accumulate As(V) in the order of roots > stems > leaves. • The fecundity of aphids was 22.4%–26.4% lower than that of the control. • The eclosion rate of parasitoids was significantly affected. • A precautionary approach must be taken when assessing the influence of As(V). [ABSTRACT FROM AUTHOR]
- Published
- 2019
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27. The toxicity of exogenous arsenic to soil-dwelling springtail Folsomia candida in relation to soil properties and aging time.
- Author
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Lin, Xianglong, Sun, Zaijin, Zhao, Long, Ma, Jin, Li, Xing, He, Fei, and Hou, Hong
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ARSENIC poisoning ,SEMIMETALS ,REGRESSION analysis ,TOXICITY testing ,CANDIDA - Abstract
Abstract Arsenic (As) is a toxic metalloid, but studies on As toxicity to soil-dwelling springtails are fairly limited, and did not consider the effects of various soil properties and long aging time. To address this, the toxicity of As to model organism— Folsomia candida were evaluated in the laboratory studies. The results showed that compared to the soils aged only for 15 d, the concentrations inhibiting 50% reproduction (EC 50) significantly increased by 1.3- to 2.0-fold in four soils aged for 150 d, the concentrations causing 50% mortality (LC 50) were higher than the highest test concentration in the most soils. Furthermore, the aging effects correlated significantly with soil free Fe oxides contents. The toxicity of As differed in ten soils aged for 150 d, the LC 50 were 320–> 1280 mg/kg in acute test and the EC 50 were 67–580 mg/kg in chronic test. Regression analysis indicated that soil clay was the most important single factor predicting soil As toxicity to reproduction, explaining 89% of the variance in EC 50 values. Soil pH, free Fe oxides and Al oxides could also well explain the toxicity variance (> 65%), indicating that As sorption was a key factor controlling its toxicity. Highlights • Toxicity of As to springtail decreased significantly after aging for 150 d. • The effects of aging on As toxicity to springtail correlated significantly with free Fe oxides. • Prediction models of As toxicity to springtail as a function of soil properties were developed. • Soil clay was the most important single factor predicting soil As toxicity to springtails. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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28. Long-term effectiveness of sediment dredging on controlling the contamination of arsenic, selenium, and antimony.
- Author
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Sun, Qin, Ding, Shiming, Chen, Musong, Gao, Shuaishuai, Lu, Guanghua, Wu, Yuexia, Gong, Mengdan, Wang, Dan, and Wang, Yan
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SEDIMENTS ,ARSENIC ,DIALYSIS (Chemistry) ,SEMIMETALS ,ANTIMONY - Abstract
Abstract This study assessed the effectiveness of dredging in controlling arsenic (As), selenium (Se), and antimony (Sb) contamination in sediments, by examining contaminant concentrations in sediments six years after dredging was completed. High-resolution diffusive gradients in thin films (DGT) and dialysis (HR-Peeper) techniques were used to monitor the concentrations of DGT-labile metalloids and soluble metalloids in sediments, respectively. Results revealed that dredging effectively remediated metalloid contamination in sediments only in April, July and/or January. Compared to non-dredged sediments, the concentrations of soluble and DGT-labile As, Se, and Sb in dredged sediments decreased on average by 42%, 52%, and 43% (soluble), and 54%, 50%, and 53% (DGT), respectively. The effectiveness of the dredging was primarily due to the transformation of metalloids from labile to inert fractions, which increased the ability of the sediments to retain the metalloids, and the slowed rate of resupplied metalloids from available solid pools. In contrast, negligible/negative effects of dredging were seen in October, and the concentrations of soluble and DGT-labile metalloids even increased in some profiles of dredged sediments. This was mainly caused by a release of the metalloids from algal degradation, which may offset the dredging effectiveness. Graphical abstract Image 1 Highlights • Dredging effects varied by season, reflected by metalloid concentrations. • Dredging was most effective in April, July and/or January. • Efficacy due to higher fraction of inert metalloids with slower kinetic response. • Dredging had negligible and negative effects in October. • Algal decomposition and metalloid release suppressed dredging efficacy. [ABSTRACT FROM AUTHOR]
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- 2019
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29. Selenium and zinc protections against metal-(loids)-induced toxicity and disease manifestations: A review.
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Rahman, Md. Mostafizur, Hossain, Kaniz Fatima Binte, Banik, Subrata, Sikder, Md. Tajuddin, Akter, Mahmuda, Bondad, Serene Ezra Corpus, Rahaman, Md. Shiblur, Hosokawa, Toshiyuki, Saito, Takeshi, and Kurasaki, Masaaki
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SEMIMETALS ,NEUROLOGICAL disorders ,INDUSTRIAL applications ,BIOLOGICAL systems ,METAL toxicology ,HOMEOSTASIS - Abstract
Abstract Metals are ubiquitous in the environment due to huge industrial applications in the form of different chemicals and from extensive mining activities. The frequent exposures to metals and metalloids are crucial for the human health. Trace metals are beneficial for health whereas non-essential metals are dangerous for the health and some are proven etiological factors for diseases including cancers and neurological disorders. The interactions of essential trace metals such as selenium (Se) and zinc (Zn) with non-essential metals viz. lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in biological system are very critical and complex. A huge number of studies report the protective role of Se and Zn against metal toxicity, both in animal and cellular levels, and also explain the numerous mechanisms involved. However, it has been considered that a tiny dyshomeostasis in the metals/trace metals status in biological system could induce severe deleterious effects that can manifest to numerous diseases. Thus, in this particular review, we have demonstrated the critical protection mechanism/s of Se and Zn against Cd, Pb, As and Hg toxicity in a one by one manner to clarify the up-to-date findings and perspectives. Furthermore, biomolecular consequences are comprehensively presented in light of particular cellular/biomolecular events which are somehow linked to a subsequent disease. The analyzed reports support significant protection potential of Se and Zn, either alone or in combination with other agents, against each of the abovementioned non-essential metals. However, Se and Zn are still not being used as detoxifying agents due to some unexplained reasons. We hypothesized that Se could be a potential candidate for detoxifying As and Hg regardless of their chemical speciations, but requires intensive clinical trials. However, particularly Zn-Hg interaction warrants more investigations both in animal and cellular level. Highlights • Adverse health outcome due to environmental exposure of metals is obvious. • Oxidative stress induction is pivotal regulator of metal-induced toxicity. • Se and Zn possesses potential to detoxify metals toxicity in biological systems. • Se and Zn has different mechanism/s against metals' toxicity in vitro and in vivo. • Detoxification potential of trace metals warrants more study against metal toxicity. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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30. Blood-cerebrospinal fluid barrier permeability of metals/metalloids and its determinants in pediatric patients.
- Author
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Wu, Weixiang, Ruan, Xiaolin, Gu, Chunming, Dan Luo, Ye, Jinfeng, Diao, Fuqiang, Wu, Lihong, and Luo, Mingyong
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BLOOD-brain barrier ,CEREBROSPINAL fluid examination ,SEMIMETALS ,MOLYBDENUM ,INDUCTIVELY coupled plasma mass spectrometry ,CHILD patients ,LEAD ,COPPER - Abstract
Concerns regarding adverse effects of metal/metalloids exposure on brain development and neurological disorders among children are increasing. However, the transport patterns of metals/metalloids across the blood-cerebrospinal fluid barrier (BCSFB) need to be clarified in children. A total of 99 Chinese pediatric patients were enrolled from February 2020 to August 2021, with a median age of 6.76 months. We detected 16 metal/metalloid levels in matched serum and cerebrospinal fluid (CSF) samples using inductively coupled plasma mass spectrometry. The BCSFB permeability of metals/metalloids were estimated and the potential effects of biomedical parameters were explored. Most metals/metalloids were detectable among > 80.0% of CSF samples. Significant correlations were observed between strontium (Sr, r = 0.46), molybdenum (Mo, r = 0.50), and cadmium (Cd, r = 0.24) concentrations in serum and CSF (P < 0.05). Ratios of metal/metalloid levels in CSF to serum (R metal) ranged from 0.02 to 0.74, and hazardous metals/metalloids including arsenic (As), Cd, lead (Pb), thallium (Tl), and manganese (Mn) showed high transfer efficiencies across the BCSFB (R metals > 0.5). With the adjustment of age and sex, albumin, β2-microglobulin, and total protein levels in CSF were positively associated with copper (Cu) permeability (FDR-adjusted P < 0.05), while glucose in CSF was negatively correlated with calcium (Ca), Cu, Sr, and Mo BCSFB permeability (FDR-adjusted P < 0.05). Q-Alb promoted Cu permeability across the BCSFB (FDR-adjusted P < 0.001), while C-reactive protein levels in serum were positively associated with selenium (Se) permeability (FDR-adjusted P = 0.046). For the first time, our findings provided data for the BCSFB permeability of 16 metals/metalloids in children, and indicated that some biomedical parameters could influence the transformation of metals/metalloids from serum to CSF. Metals/metalloids with strong BCSFB permeability warrant attention for their potential neurotoxicity. [Display omitted] • Most metals/metalloids were detectable in > 80.0% of the CSF samples. • Levels of Sr, Mo, and Cd in serum were correlated with those in the CSF samples. • As, Cd, Pb, Tl, and Mn showed a high BCSFB permeability in pediatric patients. • CSF Parameters and serum CRP levels are related to the BCSFB permeability of metals. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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31. Metal and metalloid bioaccumulation in dried red seaweed Hypnea musciformis and health risk assessment for consumers.
- Author
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Siddique, Mohammad Abdul Momin, Hossain, Md. Shakhawate, Chakma, Bibhuti, Islam, Md. Mohidul, Hossain, Md. Murad, Shazada, Nururshopa Eskander, and Walker, Tony R.
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HEAVY metals ,HEALTH risk assessment ,SEMIMETALS ,COPPER ,CONSUMERS ,METALS - Abstract
This study measured 22 metal and metalloid concentrations in Hypnea musciformis from the Bakkhali River estuary and Saint Martin's Island, Bangladesh and determined their potential impact on consumption. Student t -tests showed a significant variation in metal concentrations between the two sampling sites (p < 0.05). Mean concentrations of Co (2.49 ± 0.05 mg/kg), Fe (793.29 ± 11.76 mg/kg), Mn (368.72 ± 4.87 mg/kg), Pb (3.82 ± 0.02 mg/kg), V (11.23 ± 0.20 mg/kg) and Zn (16.60 ± 0.28 mg/kg) were higher in samples collected from the Bakkhali River estuary compared to Saint Martin's Island, while mean concentrations of Ca (484.18 ± 4.68 mg/kg), Cd (2.44 ± 0.03 mg/kg), Mg (2112.70 ± 17.80 mg/kg), Mo (1.57 ± 0.06 mg/kg), Sr (2377.57 ± 29.98 mg/kg), and Ti (258.27 ± 4.62 mg/kg) were higher in samples collected from Saint Martin's Island. Eight heavy metals (Pb, Cd, Zn, Cu, Ni, Mn, Cr, Fe) were used to assess potential health risks for adults, but no potential health risk was detected (HQ value>1). This study reveals positive Se-HBV for H. musciformis collected from both sampling sites, indicating no potential risks involved with Hg toxicity. • Analysis of 22 metals and metalloids was performed by ICP-MS for human food safety. • Consuming H. musciformis from both sites had no potential health risk (HQ > 1). • Se-HBV indicates no potential risks involved with Hg toxicity for both sites. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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32. Changes in oral bioaccessibility of heavy metals in non-digestive sucking habits due to the formation of complexes between digestive fluid components and metals/metalloids.
- Author
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Baek, Dong-Jun, Moon, Deok Hyun, Kwon, Seon-Woo, Kim, Haeun, Yoon, Sang-Gyu, Chavan, Ganesh T., Kwon, Jung-Hwan, and An, Jinsung
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HEAVY metals ,SEMIMETALS ,ARTIFICIAL saliva ,COPPER ,METALS ,METAL products - Abstract
Humans, especially infants, are exposed to harmful substances through various means, including non-nutritive sucking behaviors. Here, we compared the "one-compartment model" and the "three-compartment model" within the "suck model" to assess the oral bioaccessibility of heavy metals in various products and evaluated whether these models can be employed to assess 12 heavy metals present in consumer products. Several certified reference materials, including plastic, paint, glass, and metals, were employed to ensure sample homogeneity. By comparing the two models, we validated that a considerable amount of complexes were formed between saliva components and the extracted heavy metals and that some of these complexes dissociated during reactions with the gastric/intestinal fluids. Furthermore, we observed that in the cases of Cu and Pb, additional complexes were formed as a result of reactions with gastric/intestinal fluids. We measured the total concentrations of the extracted heavy metals using artificial saliva through acid digestion and found that up to 99.7% of the heavy metals participated in the formation of complexes, depending on the characteristics of the sample (e.g., composition) and the target element. This result indicates that the current suck model may notably underestimate the oral bioaccessibility of heavy metals in products associated with sucking behaviors. Therefore, we propose a more conservative and simpler test method for assessing oral bioaccessibility of heavy metals that involves measuring the total concentrations of heavy metals extracted from consumer products using artificial saliva. By doing so, we can account for potential variations in the digestive milieu (e.g., due to ingested food) and the inconsistency in complex formation-dissociation characteristics. [Display omitted] • We compared two models for assessing heavy metal oral bioaccessibility in products. • Complexes formed between extracted heavy metals and the digestive fluid components. • Up to 99.7% of the heavy metals participated in complex formation. • We propose a simpler method to assess the oral bioaccessibility of heavy metal. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
33. Metal and metalloid bioaccumulation in dried red seaweed Hypnea musciformis and health risk assessment for consumers.
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Siddique, Mohammad Abdul Momin, Hossain, Md. Shakhawate, Chakma, Bibhuti, Islam, Md. Mohidul, Hossain, Md. Murad, Shazada, Nururshopa Eskander, and Walker, Tony R.
- Subjects
HEAVY metals ,HEALTH risk assessment ,SEMIMETALS ,COPPER ,CONSUMERS ,METALS - Abstract
This study measured 22 metal and metalloid concentrations in Hypnea musciformis from the Bakkhali River estuary and Saint Martin's Island, Bangladesh and determined their potential impact on consumption. Student t -tests showed a significant variation in metal concentrations between the two sampling sites (p < 0.05). Mean concentrations of Co (2.49 ± 0.05 mg/kg), Fe (793.29 ± 11.76 mg/kg), Mn (368.72 ± 4.87 mg/kg), Pb (3.82 ± 0.02 mg/kg), V (11.23 ± 0.20 mg/kg) and Zn (16.60 ± 0.28 mg/kg) were higher in samples collected from the Bakkhali River estuary compared to Saint Martin's Island, while mean concentrations of Ca (484.18 ± 4.68 mg/kg), Cd (2.44 ± 0.03 mg/kg), Mg (2112.70 ± 17.80 mg/kg), Mo (1.57 ± 0.06 mg/kg), Sr (2377.57 ± 29.98 mg/kg), and Ti (258.27 ± 4.62 mg/kg) were higher in samples collected from Saint Martin's Island. Eight heavy metals (Pb, Cd, Zn, Cu, Ni, Mn, Cr, Fe) were used to assess potential health risks for adults, but no potential health risk was detected (HQ value>1). This study reveals positive Se-HBV for H. musciformis collected from both sampling sites, indicating no potential risks involved with Hg toxicity. • Analysis of 22 metals and metalloids was performed by ICP-MS for human food safety. • Consuming H. musciformis from both sites had no potential health risk (HQ > 1). • Se-HBV indicates no potential risks involved with Hg toxicity for both sites. [ABSTRACT FROM AUTHOR]
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- 2023
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34. Associations of circulating multiple metals with the risk of incident hyperuricemia and the average annual change in uric acid levels.
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Xu, Jianjian, You, Yutong, Yuan, Yu, Wang, Hao, Wu, Tangchun, and Long, Pinpin
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URIC acid ,ARSENIC ,SEMIMETALS ,CARDIOVASCULAR diseases risk factors ,HYPERURICEMIA ,METALS ,DISEASE risk factors - Abstract
Hyperuricemia has been linked to exposure to certain metals in cross-sectional studies. However, prospective studies evaluating the associations of multiple metal exposures with incident hyperuricemia are scarce. To prospectively investigate the associations of multiple metal/metalloid concentrations with incident hyperuricemia as well as average annual change in uric acid levels in a longitudinal cohort. A longitudinal cohort study included 3957 subjects who were free of cardiovascular disease with certain risk factors for cardiovascular disease at baseline. Incident hyperuricemia was ascertained if serum uric acid level was ≥ 420 μmol/L for men and ≥ 360 μmol/L for women during the follow-up visit in 2013. The relationships between 17 single plasma metals/metalloids and incident hyperuricemia were assessed using unconditional logistic regression models. For metals/metalloids significantly related to incident hyperuricemia, we further utilized generalized linear regression models to evaluate their associations with the average annual change in uric acid levels. Finally, we applied the weighted quantile sum (WQS) regression to investigate the joint effects of metals/metalloids on hyperuricemia risk and uric acid changes, and to identify the most significant metals. After adjusting for potential confounders, plasma aluminum, arsenic, barium, lead, strontium, vanadium, and zinc concentrations were positively associated with incident hyperuricemia in both main analyses and sensitivity analyzes. Compared to the lowest quartiles, participants in the highest quartiles had 63 %−125 % higher risks of incident hyperuricemia (all FDR < 0.05). Furthermore, the positive associations of these seven metals with an average annual uric acid increase reinforced the findings. Finally, the WQS analyses showed that plasma metals mixtures were positively associated with the risk of incident hyperuricemia (OR: 1.47; 95 % CI: 1.23, 1.76) and the average annual change in uric acid levels (β: 3.17; 95 % CI: 2.42, 3.93), and strontium and vanadium were the most heavily weighted metals, respectively. Our findings identify aluminum, arsenic, barium, lead, strontium, vanadium, and zinc exposures as independent risk factors for hyperuricemia and provide new insights into the prevention of hyperuricemia. [Display omitted] • The first study exploring the relation of multiple metals with incident hyperuricemia. • We also examined the relations of multiple metals with changes in uric acid over time. • Al, As, Ba, Pb, Sr, V, Zn were positively associated with incident hyperuricemia. • Metal mixtures increased uric acid levels, with Sr and V contributing the most. [ABSTRACT FROM AUTHOR]
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- 2023
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35. Potential ecological risks of metal(loid)s in riverine floodplain soils.
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Bhatti, Sandip Singh, Kumar, Vaneet, Kumar, Anupama, Gouzos, John, Kirby, Jason, Singh, Jaswinder, Sambyal, Vasudha, and Nagpal, Avinash Kaur
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FLOODPLAINS ,SOILS ,LAND use ,SEMIMETALS ,HUMUS - Abstract
Abstract The quality of soils under different land uses is getting deteriorated throughout the world due to various anthropogenic activities. This deterioration is highly complex in riverine floodplain areas due to contamination by multiple point and non-point sources and change in seasons. Therefore, a study was conducted to analyze seasonal (pre and post-monsoon) variations in physico-chemical characteristics, contents of metal(loid)s (Al, As, Cd, Cr, Co, Cu, Fe, Mn, Mo, Ni, Pb, Sb and Zn) in riverine floodplain soils under three land uses (agricultural, riverbank and roadside) from areas around the rivers Beas and Sutlej in Punjab, India. Further, analysis was done to assess the ecological and genotoxic risks (Allium cepa genotoxicity assay) posed by metal(loid)s in these soils. It was observed that soil samples under the three land uses were slightly alkaline (pre-monsoon) to acidic (post-monsoon) in nature with sandy texture and low soil organic matter. The levels of most metal(loid)s increased in post-monsoon soil samples under the three land uses, which was attributed to increase in soil organic matter, silt and clay contents in post-monsoon samples due to precipitation, flooding and sedimentation. The ecological Risk Index (58.3–104.5) and Modified Risk Index (145.2–178.9) calculated to analyze the level of ecological risks of metal(loid)s revealed that As, Cd and Sb posed moderate to considerable ecological risks in the agricultural and roadside soils in both seasons. Allium cepa genotoxicity assay indicated that the metal(loid)s in studied soils can cause genotoxic effects in biological systems. Therefore, various steps such as reduction in use of agrochemicals, promotion of organic agricultural methods and decontamination of soils using techniques such as phytoremediation etc must be taken to ensure reduction and containment of metal(loid)s in such riverine floodplain areas. Graphical abstract fx1 Highlights • Riverine floodplain soils compared seasonally for ecological risks from metal(loid)s. • Seasonal changes significantly affected soil properties and metal(loid) contents. • Soils (three land uses) were alkaline to acidic, sandy and low in organic matter. • Metal(loid) contents higher in agricultural soils than roadside and riverbank soils. • Metal(loid) in soils posed ecological and genotoxic risks. [ABSTRACT FROM AUTHOR]
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- 2018
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36. Urban street dust bound 24 potentially toxic metal/metalloids (PTMs) from Xining valley-city, NW China: Spatial occurrences, sources and health risks.
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Li, Xiaoping, Zhang, Meng, Gao, Yu, Zhang, Yuchao, Zhang, Xu, Yan, Xiangyang, Wang, Shuo, Yang, Rui, Liu, Bin, and Yu, Hongtao
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SEMIMETALS ,SOIL pollution ,HEAVY metals ,TRACE elements ,SOIL remediation - Abstract
Street dusts (SDs) were a significant tracer to understand the pollution status of potentially toxic metal/metalloids (PTMs) in local environment. In this study, a total of 157 SDs were collected in the valley-city of Xining, NW China, with the objective to systematically investigate the spatial occurrences, sources and health risk status of 24 PTMs bound in SDs. The basic datasets of pH and size-fractions showed that the SDs with PTMs were more alkaline and dominated with the coarse particle sizes between PM10–50, respectively. Results of concentration levels and spatial status of 24 PTMs processed with multi-statistical tools well established the sources identification in monitored local areas. It was suggested that the principal elements, Al, Fe, Si, K, Ca, Na, Mg, coupled with the trace elements Bi, Ga, Nb, Ni, Rb, Sr, Th, U, Y, Zr, As, Mn, Ti, V, Ce and La would be possiblely predominated by geogenic source or nature material, whereas contamination of Ba, Cu, Pb and Zn was clearly related to traffic-related sources. Peculiar associations among Cr and Co were possiblely enriched in SDs very close to the alloy industries. However, Sb and Sn differed from other observed PTMs, which appeared to derive predominantly from the coal combustion other than sources of electronic and mechanical industries. Compared to the integrated potential ecological risk index (PERI) of all PTMs with considerable contamination level and ecological risk, the single PTM of Sb posed very high risk. Calculated Hazard Index (HI) suggested ingestion as the most important exposure pathway for the majority of PTMs in children and adults, and no significant health risks of non-carcinogenic to children and adults were found except Cr (2.78) exposured to children. However, the evaluated cancerous risk was in the acceptable range both to children and adults except for the case of Cr exposure to adults (1.55E-06) compared to other PTMs. Although the carcinogenic risk was found no significant level, the maps of spatial carcinogenic risks above the threshold for children and adults were observed in some local monitoring areas, which should be attention and not to be always ignored. [ABSTRACT FROM AUTHOR]
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- 2018
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37. Spatial variation of heavy metals in sediments within a temperate mangrove ecosystem in northern New Zealand.
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Bastakoti, Ujwal, Robertson, John, and Alfaro, Andrea C.
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HEAVY metal content of marine sediments ,MANGROVE ecology ,SEMIMETALS ,INTRACOASTAL waterways ,MARINE pollution - Abstract
Abstract Spatial dynamics of heavy metals (Cd, Cu, Fe, Pb, and Zn) and metalloid As were investigated along the sedimentary column, inside and outside mangrove stands, and within the upper, middle, and lower Mangawhai Estuary, New Zealand. Organic matter contents (1.89 to 17.15%) were 10 times higher inside versus outside mangroves, and decreased sharply with depth to 30 cm. Cu, Fe, and Zn were highest in the upper estuary and Pb was highest close to a road (lower estuary), reflecting road run-off. A mangrove island (lower estuary; high energy) had lowest heavy metal and highest As concentrations (resulting from high absorption of As by the carbonate rich sediments). Most of the analysed sediment parameters in our study were higher inside versus outside mangroves, suggesting the accumulation of organic matter and build up capacity to buffer pollutants. Our results show that mangrove stands tend to accumulate heavy metals and may act as natural filters of pollution of coastal waterways. Highlights • Heavy metals and metalloids vary inside and outside mangroves. • Accumulation of organic matter may have capacity to buffer pollutants. • Mangroves may be natural filters of pollution of coastal waterways. [ABSTRACT FROM AUTHOR]
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- 2018
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38. Supercritical water treatment of heavy metal and arsenic metalloid-bioaccumulating-biomass.
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Li, Jianxin, Chen, Jinbo, and Chen, Shan
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SUPERCRITICAL water ,WATER purification ,HEAVY metal content of water ,ARSENIC in water ,SEMIMETALS - Abstract
Hyperaccumulator biomass, as a promising resource for renewable energy that can be converted into valuable fuel productions with high conversion efficiency, must be considered as hazardous materials and be carefully treated before further reuse due to the high contents of heavy metals. In this study, Pteris vittata L., an As-hyperaccumulator biomass was treated by an effective and environmental friendly method-supercritical water gasification (SCWG) using a bench-scale batch reactor. The contents of heavy metals (Cd, Pb and Zn) and arsenic metalloid in solid, liquid and gaseous products during SCWG process were thoroughly investigated. The speciation fractions including exchangeable, reducible, oxidizable and residual fractions of each heavy metal as the proportion of the total contents in solid residue were presented and the transformations trend of these heavy metals during the SCWG process was especially demonstrated. The significant operating parameters, including reaction temperature (395–445 °C), pressure (21–27 MPa) and residence time (0–40 min) were varied to explore their effects on the contents and forms. Moreover, the environmental risks of heavy metals in solid residues were evaluated based on risk assessment code, taking into consideration the speciation fractions and bioavailability. It was highlighted that although heavy metals particularly Pb and Zn tended to accumulate in solid residues with a maximum increment of about 50% in the total content, they were mostly converted to more stable oxidizable and residual fractions, and thus the ecotoxicity and bioavailability were greatly mitigated with no obvious increase in direct toxicity fractions. Each tested heavy metal presented no or low risk to the environments after SCWG treatments, meaning that the environmental pollution levels were markedly reduced with no or low risk to the environment. This study highlights the remarkable ability of SCWG for the heavy metal stabilization. [ABSTRACT FROM AUTHOR]
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- 2018
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39. Constructed soils for mitigating lead (Pb) exposure and promoting urban community gardening: The New York City Clean Soil Bank pilot study.
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Egendorf, Sara Perl, Cheng, Zhongqi, Deeb, Maha, Flores, Victor, Paltseva, Anna, Walsh, Daniel, Groffman, Peter, and Mielke, Howard W.
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URBAN agriculture ,COMPOSTING ,ORGANIC compounds ,SEMIMETALS ,URBAN gardens - Abstract
Gardening provides a wide range of benefits to urban residents but may also increase risks of exposure to contaminants in soils. Here we evaluate the use of clean excavated glacial sediments and locally produced compost, to create soils for urban gardens in New York City, NY, USA. The objectives of this study are to examine contaminants in compost and manufactured soil, assess safety of produce, and evaluate the agronomic value of soil mixes with different ratios of sediment and compost. Methods of analysis include quantifying metal/metalloid concentrations in sediments, composts, and plant tissues, soil agronomic parameters (pH, salinity, organic matter, total nitrogen, total carbon), and crop yield. Contaminant levels in sediments from the New York City Clean Soil Bank (CSB) (<10 mg Pb kg −1 ) were far below background levels of soils in two selected gardens (66 and 1025 mg Pb kg −1 ), while available composts had highly variable levels of contamination (10–232 mg Pb kg −1 ). A relatively clean compost was used for this study (19 mg Pb kg −1 ). Metal/metalloid levels did not increase in constructed soils during the 1-year pilot study period, and crops were well below EU safety standards of 0.1 and 0.3 mg Pb kg −1 for fruits and leafy greens, even when surrounded by contaminated soils. Sediment/compost mixtures produced yields comparable to control plots. Results suggest that CSB sediments have high potential to serve as manufactured topsoil. Creating these soil mixtures diverts materials from expensive waste disposal, reduces contamination risks for urban residents, and promotes the myriad benefits of urban agriculture and community gardening. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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40. Phytofiltration of arsenic by aquatic moss (Warnstorfia fluitans).
- Author
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Sandhi, Arifin, Landberg, Tommy, and Greger, Maria
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WETLANDS ,ARSENATES ,SEMIMETALS ,ARSENIC & the environment ,ARSENIC removal (Water purification) - Abstract
This work investigates whether aquatic moss ( Warnstorfia fluitans ) originating from an arsenic (As)-contaminated wetland close to a mine tailings impoundment may be used for phytofiltration of As. The aim was to elucidate the capacity of W. fluitans to remove As from arsenite and arsenate contaminated water, how nutrients affect the As uptake and the proportion of As adsorption and absorption by the moss plant, which consists of dead and living parts. Arsenic removal from 0, 1, or 10% Hoagland nutrient solution containing 0–100 μM arsenate was followed over 192 h, and the total As in aquatic moss after treatment was analysed. The uptake and speciation of As in moss cultivated in water containing 10 μM arsenate or arsenite were examined as As uptake in living (absorption + adsorption) and dead (adsorption) plant parts. Results indicated that W. fluitans removed up to 82% of As from the water within one hour when 1 μM arsenate was added in the absence of nutrients. The removal time increased with greater nutrient and As concentrations. Up to 100 μM As had no toxic effect on the plant biomass. Both arsenite and arsenate were removed from the solution to similar extents and, independent of the As species added, more arsenate than arsenite was found in the plant. Of the As taken up, over 90% was firmly bound to the tissue, a possible mechanism for resisting high As concentrations. Arsenic was both absorbed and adsorbed by the moss, and twice as much As was found in living parts as in dead moss tissue. This study revealed that W. fluitans has potential to serve as a phytofilter for removing As from As-contaminated water without displaying any toxic effects of the metalloid. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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41. Bioaccumulation and sources of metal(loid)s in lilies and their potential health risks.
- Author
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Sun, Haixu, Cheng, Hongguang, Lin, Longzhun, Deng, Ke, and Cui, Xiangfen
- Subjects
BIOACCUMULATION ,SEMIMETALS ,LILIES ,TRACE elements ,LEAD ,BIOCONCENTRATION ,CARCINOGENICITY - Abstract
Dietary intake of metal(loid)s can seriously affect human health, but the levels, the bioaccumulation, sources and related health risks of As, Cd, Cr and Pb in cultivated lilies, particularly for Lilium davidii var. unicolor , remain unresolved. We collected 35 lily samples aged 1–6 years from farmlands of two types of soil (heilu soils and loessal soils) in Qilihe district in 2016 and analysed the concentrations of As, Cd, Cr and Pb in bulbs, the soil-bulb bioaccumulation and the potential sources of these elements in bulbs. Non-carcinogenic and carcinogenic risks by consuming lilies were also assessed. Concentrations of four elements decreased in the order of Cr > Pb > Cd > As, and soil-bulb BCFs in the order of BCF Cd > BCF Cr > BCF Pb > BCF As. The Cd concentration of bulbs of lilies which grew in heilu soils was statistically higher than that of bulbs of lilies which grew in loessal soils, and the Cd concentration of bulbs of lilies aged 1–3 years was statistically higher than that of bulbs of lilies aged 4–6 years. Levels and soil-bulb BCFs of Cr and Pb of two-bulbed lilies were statistically higher than those of one-bulbed lilies. Farmyard manure may be a primary source of Cd in soil. There existed overall potential non-carcinogenic effects by exposure to the combination of four elements. Dietary intake of Cr posed carcinogenic risks to both adults and children. Non-carcinogenic and carcinogenic risks were higher for adults than children. Concluding, the edible parts of lily were significantly polluted by Cr and Pb but not by As and Cd. The number of bulbs significantly impacted concentrations and soil-bulb BCFs of Cr and Pb, but the reason for which needs further studies. Non-carcinogenic and carcinogenic risks caused by lily consumption should not be neglected. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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42. Accumulation patterns and risk assessment of metals and metalloid in muscle and offal of free-range chickens, cattle and goat in Benin City, Nigeria.
- Author
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Ogbomida, Emmanuel Temiotan, Fasipe, Iriagbonse Priscillia, Nakayama, Shouta M.M., Bortey-Sam, Nesta, Oroszlany, Balazs, Mizukawa, Hazuki, Ishizuka, Mayumi, Ikenaka, Yoshinori, Tongo, Isioma, Enuneku, Alex Ajeh, Ozekeke, Ogbeide, Ainerua, Martins Oshioriamhe, and Ezemonye, Lawrence Ikechukwu
- Subjects
HEAVY metals ,SEMIMETALS ,CHICKENS ,POLLUTANTS ,RUMINANTS ,ENVIRONMENTAL health ,RISK assessment - Abstract
The use of free range animals for monitoring environmental health offers opportunities to detect exposure and assess the toxicological effects of pollutants in terrestrial ecosystems. Potential human health risk of dietary intake of metals and metalloid via consumption of offal and muscle of free range chicken, cattle and goats by the urban population in Benin City was evaluated. Muscle, gizzard, liver and kidney samples were analyzed for Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, and Pb concentrations using inductively coupled plasma mass spectrometer (ICP-MS) while Hg was determined using Hg analyzer. Mean concentrations of metals (mg/kg ww) varied significantly depending upon the tissues and animal species. Human health risk estimations for children and adults showed estimated daily intake (EDI) values of tissues below oral reference dose (RfD) threshold for non essential metals Cd, As, Pb and Hg thus strongly indicating no possible health risk via consumption of animal based food. Calculated Hazard quotient (THQ) was less than 1 (< 1) for all the metals analyzed for both adult and children. However, Cd and As had the highest value of THQ suggestive of possible health risk associated with continuous consumption of Cd and As contaminated animal based foods. Hazard Index (HI) for additive effect of metals was higher in chicken liver and gizzard for children and chicken liver for adults. Thus, HI indicated that chicken liver and gizzard may contribute significantly to adult and children dietary exposure to heavy metals. Principal component analysis (PCA) showed a clear species difference in metal accumulation between chickens and the ruminants. This study provides baseline data for future studies and also valuable evidence of anthropogenic impacts necessary to initiate national and international policies for control of heavy metal and metalloid content in food items. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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43. Distribution of metal and metalloid elements in human scalp hair in Taiyuan, China.
- Author
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Zhu, Yuen, Wang, Yuzhe, Meng, Fanjian, Li, Lifen, Wu, Shan, Mei, Xiaohui, Li, Hua, Zhang, Guixiang, and Wu, Daishe
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HAIR analysis ,METALS in the body ,SEMIMETALS ,BIOACCUMULATION ,INDUSTRIAL districts - Abstract
This study investigated the levels of metal and metalloid elements (As, Ca, Cd, Cr, Cu, Fe, Hg, Mg, Ni, Pb, and Zn) in scalp hair samples collected from 161 people of different age and gender groups living in the six districts of Taiyuan, an industrial city with rich coal reserve in Shanxi province in China. Levels of most elements in the hair were high in the 26–40 age groups and increased with the length of residence. Calcium, Cr, Mg, Ni and Zn levels in the females’ hair were significantly higher than those in the males’ ( p < 0.05). Element levels in the hair didn’t have significantly differences between industrial and non-industrial districts because most of industry factories are in the upper wind position in Taiyuan, and contamination is prone to spread to non-industrial districts. The principal component analysis indicates that the main sources of these elements are mining activities, the neighboring stainless steel industry, and coal combustion. These results indicate that the industrial activities primarily contribute to the metal and metalloid pollution in Taiyuan, whereas numerous factors caused the metals accumulation in hair. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
44. Blood metal/metalloid concentration of male subjects undergoing IVF/ICSI treatment outcomes: A prospective cohort study.
- Author
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Shi, Xiao, Ren, Mei Qi, Wang, Lian Tong, Chan, Carol Pui Shan, Chan, David Yiu Leung, Quan, Song, and Li, Tin-Chiu
- Subjects
HEAVY metals ,FROZEN human embryos ,INDUCTIVELY coupled plasma mass spectrometry ,FERTILIZATION in vitro ,INTRACYTOPLASMIC sperm injection ,SEMIMETALS ,OVARIAN follicle - Abstract
Previous epidemiology studies reported that heavy metal/metalloid exposure is associated with the impairment of semen quality. However, it is still not clear whether the in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) treatment outcome will be affected after the heavy metal/metalloid exposure of the male partners. A prospective cohort study with a 2-year followed-up was conducted in a tertiary IVF center. A total of 111 couples undergoing IVF/ICSI treatment were initially recruited from November 2015 to November 2016. Male blood concentrations of heavy metal/metalloid including Ca, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, Cd, Hg, and Pb were measured by inductively coupled plasma mass spectrometry, and the lab and pregnancy outcome data were followed up. The associations between male blood heavy metal/metalloid concentration and the clinical outcomes were analyzed by Poisson regression analysis. Our results showed that none of the heavy metal/metalloid of male partners we investigated are significantly associated with the oocyte fertilization and good embryo (P ≥ 0.05); however, antral follicle count (AFC) was a protective factor for the oocyte fertilization (RR: 1.07, 95 % CI: 1.04–1.10). The blood Fe concentration of the male partner was positively associated (P < 0.05) with pregnancy in the first fresh cycle (RR:170.93, 95 % CI: 4.13–7082.04), cumulative pregnancy (RR: 23.61, 95 % CI: 3.25–171.64) and cumulative live birth (RR: 36.42, 95 % CI: 1.21–1092.54). In the first frozen embryo cycles, pregnancy was significantly associated (P < 0.05) with the blood Mn (RR: 0.01, 95 % CI:0.00–0.11) and Se concentration (RR: 0.01, 95 % CI:8.25 E-5–0.47) and female age (RR: 0.86, 95 % CI:0.75–0.99); live birth was significantly associated (P < 0.05) with the blood Mn concentration (RR: 0.00, 95 % CI: 1.14E-7–0.51). Our results suggested that the higher male blood Fe concentration was positively associated with pregnancy in the fresh embryo transfer cycle, cumulative pregnancy, and cumulative live birth, whereas the higher male blood Mn and Se concentration were associated with lower chance of pregnancy and live birth in the frozen embryo transfer cycle. However, the underline mechanism of this finding still needs further investigation. [ABSTRACT FROM AUTHOR]
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- 2023
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45. A heavy burden: Metal exposure across the land-ocean continuum in an adaptable carnivore.
- Author
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Parker, Kim H., Bishop, Jacqueline M., Serieys, Laurel E.K., Mateo, Rafael, Camarero, Pablo R., and Leighton, Gabriella R.M.
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HEAVY metals ,METALS ,LEAD ,ARSENIC ,POLLUTION monitoring ,SEMIMETALS ,BIODIVERSITY conservation - Abstract
Urbanisation and associated anthropogenic activities release large quantities of toxic metals and metalloids into the environment, where they may bioaccumulate and threaten both wildlife and human health. In highly transformed landscapes, terrestrial carnivores may be at increased risk of exposure through biomagnification. We quantified metallic element and metalloid exposure in blood of caracals (Caracal caracal), an adaptable felid inhabiting the rapidly urbanising, coastal metropole of Cape Town, South Africa. Using redundancy analysis and mixed-effect models, we explored the influence of demography, landscape use, and diet on the concentration of 11 metals and metalloids. Although species-specific toxic thresholds are lacking, arsenic (As) and chromium (Cr) were present at potentially sublethal levels in several individuals. Increased use of human-transformed landscapes, particularly urban areas, roads, and vineyards, was significantly associated with increased exposure to aluminium (Al), cobalt (Co) and lead (Pb). Foraging closer to the coast and within aquatic food webs was associated with increased levels of mercury (Hg), selenium (Se) and arsenic, where regular predation on seabirds and waterbirds likely facilitates transfer of metals from aquatic to terrestrial food webs. Further, several elements were linked to lower haemoglobin levels (chromium, mercury, manganese, and zinc) and elevated levels of infection-fighting cells (mercury and selenium). Our results highlight the importance of anthropogenic activities as major environmental sources of metal contamination in terrestrial wildlife, including exposure across the land-ocean continuum. These findings contribute towards the growing evidence suggesting cities are particularly toxic areas for wildlife. Co-exposure to a suite of metal pollutants may threaten the long-term health and persistence of Cape Town's caracal population in unexpected ways, particularly when interacting with additional known pollutant and pathogen exposure. The caracal is a valuable sentinel for assessing metal exposure and can be used in pollution monitoring programmes to mitigate exposure and promote biodiversity conservation in human-dominated landscapes. [Display omitted] • Widespread metal and metalloid exposure in Cape Town's caracals. • Higher metal burden with increased use of human-associated landscapes. • Dietary exposure to metals facilitated by seabird and waterbird prey. • Metal contamination linked to potential anaemia and elevated immune response. • Metal exposure takes place across the land-ocean continuum. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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46. Heavy metals and metalloid in aquatic invertebrates: A review of single/mixed forms, combination with other pollutants, and environmental factors.
- Author
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Jeong, Haksoo, Byeon, Eunjin, Kim, Duck-Hyun, Maszczyk, Piotr, and Lee, Jae-Seong
- Subjects
AQUATIC invertebrates ,PLASTIC marine debris ,HEAVY metals ,PERSISTENT pollutants ,POLLUTANTS ,SEMIMETALS - Abstract
Heavy metals (HMs) and metalloid occur naturally and are found throughout the Earth's crust but they are discharged into aquatic environments at high concentrations by human activities, increasing heavy metal pollution. HMs can bioaccumulate in higher organisms through the food web and consequently affect humans. In an aquatic environment, various HMs mixtures can be present. Furthermore, HMs adsorb on other environmental pollutants, such as microplastics and persistent organic pollutants, causing a synergistic or antagonistic effect on aquatic organisms. Therefore, to understand the biological and physiological effects of HMs on aquatic organisms, it is important to evaluate the effects of exposure to combinations of complex HM mixtures and/or pollutants and other environmental factors. Aquatic invertebrates occupy an important niche in the aquatic food chain as the main energy link between higher and lower organisms. The distribution of heavy metals and the resulting toxic effects in aquatic invertebrates have been extensively studied, but few reports have dealt with the relationship between HMs, pollutants, and environmental factors in biological systems with regard to biological availability and toxicity. This review describes the overall properties of individual HM and their effects on aquatic invertebrates and comprehensively reviews physiological and biochemical endpoints in aquatic invertebrates depending on interactions among HMs, other pollutants, and environmental factors. [Display omitted] • HMs and metalloid exist in single and mixed forms and interact with a variety of pollutants and environmental factors. • All aquatic invertebrates ingest and accumulate HMs and metalloid, and the fate of those HMs exhibits enormous variability. • Aquatic invertebrate exposure to HMs and metalloid causes a variety of physiological and biochemical toxicities. • The toxic effects of HMs and metalloids can be altered by interactions with other pollutants and environmental factors. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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47. Pelagic and estuarine birds as sentinels of metal(loid)s in the South Atlantic Ocean: Ecological niches as main factors acting on bioaccumulation.
- Author
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Lima, Guilherme dos Santos, Menegario, Amauri Antonio, Suarez, Carlos Alfredo, Kamazuka, Silvia Harumi, Gemeiner, Hendryk, Sánchez-Sarmiento, Angélica Maria, Ferioli, Raquel Beneton, and Barreto, André Silva
- Subjects
ECOLOGICAL niche ,TRACE elements in water ,ENERGY development ,METALS ,COPPER ,PETROLEUM prospecting ,SEMIMETALS - Abstract
Activities related to the offshore exploration and production of oil and natural gas provide economic development and an essential energy source. However, besides the risk of petroleum hydrocarbon contamination, these activities can also be sources of metals and metalloids for marine organism contamination. In this research, we evaluated the potential use of two pelagic (black-browed albatross Thalassarche melanophris and yellow-nosed albatross T. chlororhynchos) and one estuarine bird species (neotropical cormorant Nannopterum brasilianus) as sentinels of contamination of As, Cd, Cr, Cu, Pb, Mn, Mo, Zn, Ni, Ba, V, and Hg in an area under influence of oil and gas activities. The analyses were carried out in samples collected from 2015 to 2022 from 97 individuals. A factor alert; an adaptation from the contamination factor is proposed to identify individuals with high concentrations that possibly suffered contamination by anthropogenic origin. Grouping all species, the metal(loid)s with the highest concentrations were in decreasing order: Zn > Cu > Mn > Hg > As > Cd > Mo > V > Cr > Ba > Ni > Pb. Similar concentrations were observed for V, Mn, Cr and Pb among the three species. Pelagic birds showed higher levels of concentrations for Hg, As and Cd. Based on the correlations and multivariate analysis performed, the results indicate that the ecological niche factor has greater relevance in the bioaccumulation of these elements compared to the habitat. Although some individuals showed high concentrations in part of the trace elements, suggesting exposure to anthropic sources, the direct influence of oil production and exploration activities was not observed, suggesting that activities on the continent are the primary contamination source. The results of this work highlight the role of seabirds as sentinels for metal(loid)s, contributing to the knowledge of the occurrence of contaminants in the South Atlantic Ocean. [Display omitted] • Liver trace elements were measured in albatrosses and cormorants. • As, Cd and Hg were higher in albatrosses. • No correlation was observed between oil production and metals in birds. • High concentrations that may pose a risk to the birds' health were found. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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48. Predicting criteria continuous concentrations of metals or metalloids for protecting marine life by use of quantitative ion characteristic–activity relationships–species sensitivity distributions (QICAR-SSD).
- Author
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Qie, Yu, Chen, Cheng, Guo, Fei, Mu, Yunsong, Sun, Fuhong, Wang, Hao, Wang, Ying, Wang, Huanhua, Wu, Fengchang, Hu, Qing, Dang, Zhi, and Giesy, John P.
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SEMIMETALS ,MARINE biology ,MARINE pollution ,WATER quality ,METAL content of water - Abstract
Marine pollution by metals has been a major challenge for ecological systems; however, water quality criteria (WQC) for metals in saltwater is still lacking. Especially from a regulatory perspective, chronic effects of metals on marine organisms should receive more attention. A quantitative ion characteristic–activity relationships–species sensitivity distributions (QICAR-SSD) model, based on chronic toxicities for eight marine organisms, was established to predict the criteria continuous concentrations (CCCs) of 21 metals. The results showed that the chronic toxicities of various metals had good relationships with their physicochemical properties. Predicted CCCs of six metals (Hg 2 + , Cu 2 + , Pb 2 + , Cd 2 + , Ni 2 + and Zn 2 + ) were in accordance with the values recommended by the U.S. EPA, with prediction errors being less than an order of magnitude. The QICAR-SSD approach provides an alternative tool to empirical methods and can be useful for deriving scientifically defensible WQC for metals for marine organisms and conducting ecological risk assessments. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
49. A Dataset for Three-Dimensional Distribution of 39 Elements Including Plant Nutrients and Other Metals and Metalloids in the Soils of a Forested Headwater Catchment.
- Author
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Wu, B., Wiekenkamp, I., Sun, Y., Fisher, A. S., Clough, R., Gottselig, N., Bogena, H., Pütz, T., Brüggemann, N., Vereecken, H., and Bol, R.
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PLANT nutrients ,BIOGEOCHEMISTRY ,SEMIMETALS - Abstract
Quantification and evaluation of elemental distribution in forested ecosystems are key requirements to understand element fluxes and their relationship with hydrological and biogeochemical processes in the system. However, datasets supporting such a study on the catchment scale are still limited. Here we provide a dataset comprising spatially highly resolved distributions of 39 elements in soil profiles of a small forested headwater catchment in western Germany (http://teodoor.icg.kfa-juelich.de/ibg3searchportal2/dispatch?searchparams=freetext-Wuestebach&metadata.detail.view.id=7d37ae00-20f6-408e-8660-33bfba07c869) to gain a holistic picture of the state and fluxes of elements in the catchment. The elements include both plant nutrients and other metals and metalloids that were predominately derived from lithospheric or anthropogenic inputs, thereby allowing us to not only capture the nutrient status of the catchment but to also estimate the functional development of the ecosystem. Soil samples were collected at high lateral resolution (≤60 m), and element concentrations were determined vertically for four soil horizons (L/Of, Oh, A, B). From this, a three-dimensional view of the distribution of these elements could be established with high spatial resolution on the catchment scale in a temperate natural forested ecosystem. The dataset can be combined with other datasets and studies of the TERENO (Terrestrial Environmental Observatories) Data Discovery Portal (http://teodoor.icg.kfa-juelich.de/ibg3searchportal2/index.jsp) to reveal elemental fluxes, establish relations between elements and other soil properties, and/or as input for modeling elemental cycling in temperate forested ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
50. Key role of the sorption process in alteration of metal and metalloid quantification by fouling development on DGT passive samplers.
- Author
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Devillers, Delphine, Buzier, Rémy, Grybos, Malgorzata, Charriau, Adeline, and Guibaud, Gilles
- Subjects
TRACE metals ,SEMIMETALS ,SORPTION ,FOULING ,POLYCARBONATES ,OXYANIONS - Abstract
The DGT technique (diffusive gradients in thin films) is widely used for passive sampling of labile trace metals and metalloids in natural waters. Although development of fouling on the protective membranes is frequently observed, its effect on DGT sampling has been barely investigated. This study evaluates the influence of fouling on sampling of trace cationic metals Cd(II), Cu(II), Ni(II) and Pb(II) and oxyanions As(V), Cr(VI), Sb(V) and Se(VI). Fouling was developed in situ on polycarbonate membranes in four diverse natural freshwater environments and sampling alteration was assessed in controlled laboratory experiments. Accumulation of oxyanions and Ni was unaltered in the presence of fouling whereas significant alteration occurred in sampling of Cd, Cu and Pb (at pH ∼5.4). Characterization of the fouled membranes highlighted the intervention of sorption phenomenon as sampling alteration was systematically observed alongside element sorption onto fouled membrane. A preliminary flowchart for identifying potentially biased quantifications linked to fouling development during in situ DGT deployment in natural waters is proposed. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
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