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The issue of material migration from cookware to food is one of the main concerns of consumers, and which cookware is suitable for cooking is a challenge. The answer to this question can effectively maintain the safety of consumed food. Therefore, this study investigated heavy metals' migration from the usual cookware used in cooking food in two new and old forms. Migration Cr, As, Ni, Pb, Al, Cu, Cd, Se, and Co from copper, glass, aluminium, stone, cast iron, plastic, Teflon, and stainless steel cookware was quantified by the ICP device. The results showed that the release of heavy metals increases in old containers due to frequent use and damage or abrasion. On the other hand, cooking time had a significant relationship with the release of metals in food, especially in old cookware. This study showed the release of some heavy metals into food from old cookware. Therefore, the use of high-risk damaged cookware should be restricted. [ABSTRACT FROM AUTHOR]

Featured Application: This research work demonstrates that undoped a-C:H sputtered coatings can effectively inhibit the metallic release from medical-grade 316L stainless steel in acidic artificial saliva without a significant change in the microstructural characteristics. Moreover, the in vitro biocompatibility with macrophages and/or fibroblasts was significantly improved. In opposition, the a-C:H:N system seems to be unfavorable, even for low N content up to 10 at.%. Hydrogenated amorphous carbon (a-C:H) has been considered a promising biocompatible coating to protect metallic alloys against corrosion for medical applications, namely orthodontics. However, there is still no optimal solution for this biomedical field; hence, the investigation remains open. In this work, the effect of a nonmetallic doping element (N) on sputter-deposited a-C:H coatings was studied concerning both salivary corrosion and cytotoxicity behavior. After a 30-day corrosion test in an acidic modified Fusayama-Meyer artificial saliva, metal release from both coated and uncoated 316L stainless steel (SS) substrates was quantified. Tests on the corrosion extracts were then performed by using monocultures of macrophages and fibroblasts, and their coculture; and cell viability was evaluated via the MTT test. Results show an overall inhibition of the SS corrosion, which enhanced the in vitro biocompatibility with a minimal effect on the coatings' microstructure. Among all the coatings tested, the undoped a-C:H coating performed the best, whereas an increase in N doping led to poorer protection against metal dissolution and a subsequent slightly lower biocompatibility. The findings corroborate that selecting the nonmetallic element N for doping C-based coatings is not a good choice for this biomedical field, even at low contents up to 10 at.%. [ABSTRACT FROM AUTHOR]

The increasing use of weathering steels (WS) has raised concerns regarding the diffuse emission of alloying elements. This research paper investigates the release of iron (Fe) and the alloying elements (Cr), copper (Cu), manganese (Mn) and nickel (Ni) from two commercially available WS at urban field conditions in Stockholm, Sweden, during 1 year and in the laboratory at simulated urban conditions. The amount of released metals is evaluated and compared with recommended levels of metals in drinking water and the formation and evolution of the protective patina is studied in parallel to assess the influence on the metal release process. Only minor amounts of the alloying elements are released and is only linked to the outermost surface composition of the patina during the very beginning of the exposure. The released amounts are found to be lower compared with the corresponding levels recommended by the World Health Organisation for drinking water. [ABSTRACT FROM AUTHOR]

Hydrogenated amorphous carbon (a-C:H) has been considered a promising biocompatible coating to protect metallic alloys against corrosion for medical applications, namely orthodontics. However, there is still no optimal solution for this biomedical field; hence, the investigation remains open. In this work, the effect of a nonmetallic doping element (N) on sputter-deposited a-C:H coatings was studied concerning both salivary corrosion and cytotoxicity behavior. After a 30-day corrosion test in an acidic modified Fusayama-Meyer artificial saliva, metal release from both coated and uncoated 316L stainless steel (SS) substrates was quantified. Tests on the corrosion extracts were then performed by using monocultures of macrophages and fibroblasts, and their coculture; and cell viability was evaluated via the MTT test. Results show an overall inhibition of the SS corrosion, which enhanced the in vitro biocompatibility with a minimal effect on the coatings’ microstructure. Among all the coatings tested, the undoped a-C:H coating performed the best, whereas an increase in N doping led to poorer protection against metal dissolution and a subsequent slightly lower biocompatibility. The findings corroborate that selecting the nonmetallic element N for doping C-based coatings is not a good choice for this biomedical field, even at low contents up to 10 at.%.

The electrochemical corrosion of ductile pipes (DPs) in drinking water distribution systems (DWDS) has a crucial impact on cement-mortar lining (CML) failure and metal release, potentially leading to drinking water quality deterioration and posing a risk to public health. An in-situ scanning vibrating electrode technique (SVET) with micron-scale resolution, microscopic scale detection and water quality analysis were used to investigate the corrosion behavior and metal release from DPs throughout the whole CML failure process. Metal pollutants release occurred at three different stages of CML failure process, and there are potential risks of water quality deterioration exceeding the maximum allowable levels set by national standards in the partial failure stage and lining peeling stage. Furthermore, the effects of water chemistry (Cl−, SO 4 2−, NO 3 −, and Ca2+) on corrosion scale growth and iron release activity, were investigated during the CML partial failure stage. Results showed that the CML failure process in DPs was accelerated by the autocatalysis of localized corrosion. Cl− was found to damage the uncorroded metal surface, while SO 4 2− mainly dissolved the corrosion scale surface, increasing iron release. Both the oxidation of NO 3 − and selective sedimentation of Ca2+ were found to enhance the stability of corrosion scales and inhibit iron release. [ABSTRACT FROM AUTHOR]

Sediments from three rivers in south-western Poland and their tributaries were used in a laboratory experiment on metal (Al, Cu, Ni, Cd, Zn, Fe, Mn) release. Metal migration was studied under different pH (pH 3.93, pH 7.29, pH 9.59) during 96 h. Al concentration was the highest in Bystrzyca and lowest in Strzegomka; other metal concentrations were highest in Nysa Szalona and lowest in Strzegomka. The values of pH and electrolytic conductivity increase throughout the experiment in acidic and neutral environments. Water pH decrease was observed under alkaline conditions, but conductivity reached higher values with time. The aluminum release showed an increase in values followed by a decrease. The highest aluminum amounts were released from the sediment from Nysa Szalona and the lowest from Strzegomka. The greatest aluminum migration was observed in the acidic medium. Similar observations were made for Mn and Zn: Strzegomka < Nysa Szalona < Bystrzyca. For Cu, Cd, Fe and Ni, the highest values were recorded in sediments in alkaline conditions. The amount of metals migrating from sediments to water remains at a similar level as presented by other researchers. More metals are released under acidic conditions. The most intensive migration of metals is noted at the beginning of the experiment. This experiment shows the existing trend of metals migration from the sediments to the over-bottom water, which is important from the point of view of the use of water for drinking purposes. Satisfactorily, the sediments in varied environments behave predictably enough that the quality of raw water under these conditions is not compromised, which is confirmed by environmental and health standards. The research performed concerns a specific area of southwestern Poland, for which this type of research has not been conducted. [ABSTRACT FROM AUTHOR]

There have been several attempts in enhancing corrosion jar testing methods to better mimic realworld conditions found in drinking water distribution systems. A key feature that is generally omitted in such studies is zero headspace and the lack of interaction with the atmosphere within the jars as well as the flow interactions which affect total metal release. This work proposes a modified method to typical corrosion jar testing protocols to better simulate distribution system conditions. Modified separatory funnels with the addition of a rubber stopper and coupon holder were set-up to allow an in-flow and out-flow for water replacement every three to 4 d. The results demonstrated the effectiveness and reproducibility of the modified method, specifically with the analysis of variance conducted. A synthetic water test using both the modified and original methods showed a statistical difference between the two, and decreased variability in the metal release with the new procedure. Enhanced dissolved oxygen depletion was also observed with the modified method. The results of another study conducted, using actual waters, was used to create an empirical model with the water quality parameters measured, and the total metal release. This model was a good fit, with a 0.81 R-squared value and a 0.71 linear slope between the predicted and measured copper concentrations. In addition, first-order rate law models were created for fitting the metal release observed. The resultant equations were not good fits the batch testing conducted, however, the first-rate models created for the direct-connection study resulted in up to a 0.98 R-squared value with slopes close to unity when plotting the calculated vs. measured metal release. [ABSTRACT FROM AUTHOR]

Hydrothermal processes are mainly responsible for the release and accumulation of metals and metalloids in rocks. In this work, we investigated the mineralogy and geochemistry of altered metaultramafic rocks (listvenites) that are spatially associated with Ni-Co ores near Dobšiná aiming to identify the sources of the elements in the hydrothermal Ni-Co-mineralization. Optical microscopy, electron microprobe analysis, and laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) were used to correlate the mineralogy with the degree of rock alteration. The sulfides and silicates in the metaultramafic rocks host rare, tiny inclusions of cooperite (nominally PtS), sperrylite (PtAs2), Pty-Pd-Ir-Te phase, and Pt-Au-Cr-alloy. The results show that the metaultramafic rocks were the source of Ni and Co and that platinum-group elements (PGE) were also leached and mobilized from the metaultramafic rocks. LA-ICP-MS scans show that the sulfarsenides in the metaultramafic rocks host submicrometer inclusions of PGE minerals but the hydrothermal Ni-Co sulfarsenides contain much less PGE's. These observations document the limited mobility of the PGE's. Changes in the sulfide mineralogy as a function of degree of alteration suggest that the fluids brought Fe and S, and probably a substantial amount of As whereas the metaultramafic rocks supplied Ni, Co, PGE, and perhaps also some As. [ABSTRACT FROM AUTHOR]

Mineralogical analysis and laboratory-based leaching tests coupled with speciation modeling were undertaken to quantify the potential for short-term acid generation and the release of trace elements from soils heavily contaminated with mine waste at Rio Tinto. Three different waste materials were considered as case studies: roasted pyrite, copper slags, and leached sulfide ores. The results showed elevated values of net acid generation (up to 663 mmol H+/kg), the major pools being potential sulfidic acidity and acidity retained in jarosite. Remarkable contents of As and toxic heavy metals were found especially in the slag-contaminated soil. Copper, Zn, and Pb were the most abundant metals in the acid leach solutions resulting from mine soil-water interaction, with peak values of 55.6 mg L−1, 2.77 mg L−1, and 2.62 mg L−1, respectively. Despite the high total contents of trace elements occurring in soil, the mobile fraction was limited to maximum release values of 12.60% for Cd and 10.27% for Cu, according to the test leaching. Speciation calculations indicated that free metal ions (M2+) and sulfate species (MSO40) accounted for most of the dissolved load. Acid soil drainage is a secondary source of acid and heavy metals in the mine site and, therefore, an effective land reclamation program should ensure that acidity and metal mobility are reduced to environmentally sustainable levels. [ABSTRACT FROM AUTHOR]

• HTC treatment sanitizes sewage sludge and greatly facilitates P recovery. • HTC temperature and extraction time largely influenced efficiency of P extraction. • Oxalate ions achieved the highest rate of P release at pH > 0. • Ca, Zn, Cu and Pb release with oxalate ions was notably reduced at pH > 1. • Ca and Fe oxalate precipitate was confirmed by XRD. Hydrothermal carbonization (HTC) is a treatment technique with great potential for sanitizing digested sewage sludge (SS) and converting it into valuable products. In particular, phosphorus (P) recovery from hydrothermally carbonized SS has attracted special attention in recent years. This work aims to examine the leaching efficiency of P and the consequent release of metals and heavy metals from SS hydrochars (at 180, 215 and 250 °C) using organic acids (oxalate and citrate) over a range of pH values (0–4) and extraction times (5 min-24 h). Both organic acids triggered P extraction efficiencies exceeding 75 % at the lowest pH, but only oxalate reached a nearly complete P release from hydrochars at pH > 0 and for all carbonization temperatures. Low HTC temperature (180 °C) and short extraction time (5 min) were the optimal conditions treatment for P recovery when reacted in oxalate solutions of maximal pH buffering capacity (pH = 1.4). However, oxalate leaching also transferred metals/heavy metals into the P-leachate, with the exception of Ca being retained in the solid residue from HTC as Ca-oxalate precipitate. Different characterization methods confirmed the presence of this precipitate, and provided information about the surface and morphological changes of the SS hydrochars following acid treatment. The results suggest that HTC not only a promising technique to sanitize and reduce the volume of SS, but also an efficient means for P recovery using oxalic acid, thus contributing to the circular economy of P. [ABSTRACT FROM AUTHOR]

Sarah McCarrick, Klara Midander, Magdaléna Krausová, Ulrika Carlander, Hanna L Karlsson Institute of Environmental Medicine, Karolinska Institute, Stockholm, SE-171 77, SwedenCorrespondence: Hanna L KarlssonInstitutet för Miljömedicin, C6 Biokemisk Toxikologi Karlsson, Stockholm 171 77, SwedenTel +46 8 5248-7576Email hanna.l.karlsson@ki.seIntroduction: Gold nanoparticles (AuNPs) have the potential to be used in various biomedical applications, partly due to the inertness and stability of gold. Upon intravenous injection, the NPs interact with the mononuclear phagocyte system, first with monocytes in the blood and then with macrophages in tissue. The NP–macrophage interaction will likely affect the stability of the AuNPs, but this is seldom analyzed. This study aimed to elucidate the role of macrophages in the biodissolution of AuNPs and underlying mechanisms.Methods: With an in vitro dissolution assay, we used inductively coupled plasma mass spectrometry to quantitatively compare the dissolution of 5 and 20 nm AuNPs coated with citrate or PEG in cell medium alone or in the presence of THP1-derived macrophages at 24 hours. In addition, we analyzed the cell dose, compared extra- and intracellular dissolution, and explored the possible role of reactive nitrogen species.Results: The results showed a higher cellular dose of the citrate-coated AuNPs, but dissolution was mainly evident for those sized 5 nm, irrespective of coating. The macrophages clearly assisted the dissolution, which was approximately fivefold higher in the presence of macrophages. The dissolution, however, appeared to take place mainly extracellularly. Acellular experiments demonstrated that peroxynitrite can initiate oxidation of gold, but a ligand is required to keep the gold ions in solution.Conclusion: This study suggests extracellular dissolution of AuNPs in the presence of macrophages, likely with the contribution of the release of reactive nitrogen species, and provides new insight into the fate of AuNPs in the body.Keywords: dissolution, biosolubility, metal release, nanotoxicology, transformation, fate

Introduction: The release of metallic ions from orthodontic brackets and wires typically depends on their quality (chemical composition) and the medium to which they are exposed, e.g., acidic, alkaline, substances with a high fluoride concentration, etc. This review examines corrosion and wear of orthodontic brackets, wires, and arches exposed to different media, including: beverages (juices), mouthwashes and artificial saliva among others, and the possible health effects resulting from the release of metallic ions under various conditions. Objective: This review aims to determine the exposure conditions that cause the most wear on orthodontic devices, as well as the possible health effects that can be caused by the release of metallic ions under various conditions. Sources: A search was carried out in the Scopus database, for articles related to oral media that can corrode brackets and wires. The initial research resulted in 8,127 documents, after applying inclusion and exclusion criteria, 76 articles remained. Conclusion: Stainless steel, which is commonly used in orthodontic devices, is the material that suffers the most wear. It was also found that acidic pH, alcohols, fluorides, and chlorides worsen orthodontic material corrosion. Further, nickel released from brackets and wires can cause allergic reactions and gingival overgrowth into patients.

The purpose of the present study is twofold: (i) to assess the salivary nickel, chromium, and iron concentrations and (ii) to characterize the surface microstructure of the typical commercially available Ni-containing metallic appliances during the first 12-week orthodontic treatment period. A total of 85 unstimulated saliva samples were collected from patients before treatment, after 2 days, and after 1, 4, and 12 weeks. Salivary ion concentrations were determined by inductively coupled plasma optical emission spectroscopy, and data were analyzed with the Statistical Package for Social Sciences (IBM SPSS) software. The recorded mean metal concentrations were in the ranges of 132–175 µg/L for Ni, 171–192 µg/L for Cr, and 826–1023 µg/L for Fe. No statistically significant variations were observed between the different study times, and the null hypothesis (the concentrations of metallic ions in patients' saliva did not significantly change after the placement of the orthodontic appliances) was accepted (p > 0.05). Mean salivary metallic ions were below toxic levels, and no adverse clinical reactions were registered. The intraoral surface degradation of the fixed components was corroborated by optical microscopy, scanning electron microscopy, and energy dispersive spectrometry. Microstructural analysis after complete orthodontic procedure confirmed different corrosion types, from pitting to biocorrosion. [ABSTRACT FROM AUTHOR]

Complex metal oxides (CMOs) are used broadly in applications including electroreactive forms found in lithium-ion battery technology. Computational chemistry can provide unique information about how the properties of CMO cathode materials change in response to changes in stoichiometry, for example, changes of the lithium (Li) content during the charge–discharge cycle of the battery. However, this is difficult to measure experimentally due to the small cross-sectional area of the cations. Outside of operational conditions, the Li content can influence the transformations of the CMO when exposed to the environment. For example, metal release from CMOs in aqueous settings has been identified as a cross-cutting mechanism important to CMO degradation. Computational studies investigating metal release from CMOs show that the thermodynamics depend on the oxidation states of lattice cations, which is expected to vary with the lithium content. In this work, computational studies track changes in metal release trends as a function of Li content in Lix(Ni1/3Mn1/3Co1/3)O2 (NMC). The resulting dataset is used to construct a random forest tree (RFT) machine learning (ML) model. A modeling challenge in delithiation studies is the large configurational space to sample. Through investigating multiple configurations at each lithium fraction, we find structural features associated with favorable energies to chemically guide the identification of relevant structures and adequately predict voltage values. [ABSTRACT FROM AUTHOR]

A numerical model is developed to investigate metal release from estuarine sediments. The model includes three‐dimensional (3D) large‐eddy simulation of water above the sediment‐water interface, 3D advective and diffusive transport within sediments by both physical and biological processes (bioturbation and bioirrigation), and biogeochemical processes within the sediment including reduction of electron acceptors, acid‐base reactions, and metal sorption and precipitation. The model was applied to explore the influence of overlying water chemistry and sediment chemical, physical and biological processes on metal release from sediments. Overlying water conditions (pH, salinity, oxygen saturation) may vary diurnally due to tidal cycling and control the short‐term release of metals, while over longer times (months), metals are controlled by long‐term averages of sediment convective processes (groundwater upwelling, hyporheic exchange and bioirrigation). Metal release is significantly enhanced when there is bioroughness and bioirrigation due to local oxidation of surficial sediments. Key Points: Biogeochemical processes are influenced by the interactions of bioroughness and bioirrigation driven hyporheic exchange with tidal cycling of pH and salinity in the overlying waterThe extent of surface water exchange with interstitial waters can be characterized by a hydraulic retention time and a parameter RePe1.2The release of individual metal contaminants is controlled by their speciation and potential for complexation [ABSTRACT FROM AUTHOR]

The water management initiatives in freshwater systems focus on water availability to preserve this resource for human uses and the health of aquatic ecosystems. This work presents an assessment of the potential pollution risk caused by the metal availability in suspended sediments. The objective of this study was to determine the partitioning, association, and geochemical fractionation of metals in suspended sediments from a surface water body. Additionally, the environmental assessment for this reservoir was estimated using geoaccumulation, enrichment, and pollution indices of metals and the related potential risk by their elemental availability (RAC). Chemical, mineralogical, and morphological characterizations were obtained by inductively coupled plasma spectrometry, alpha spectroscopy, X-ray crystallography, and scanning electron microscopy. Clay, quartz, montmorillonite, and calcite were the main minerals of suspended sediments. Chemical fractionation was the parameter affecting the concentrations of metals in suspended sediments. The sediment composition is of natural origin; however, these finer particles can promote the scavenging of toxic metals. It contributes to obtaining moderate to high levels for enrichment/contamination indices. Although Ca, Mg, and U were the most accessible metals for aquatic biota, metals such as Sr, Mn, Li, Cu, and Ni in the exchangeable phase of suspended sediments are the potentially toxic elements in this aquatic ecosystem. [ABSTRACT FROM AUTHOR]

Phosphorus (P) recovery from P-rich residues is crucial to sustain food and industrial demands globally, as phosphate rock reserves are being depleted. The aim of this study is to investigate the speciation and recovery of P from hydrochars (HC) of a metal-bearing sewage sludge (SS) produced by hydrothermal carbonization (HTC). We here focus on extractions by acid leaching as P cannot be directly recovered by HTC due to insoluble metal-P compounds. Acid leaching of SS and HCs was investigated using H2SO4 and HCl over a range of leaching times, and explained in terms of how composition affects P and metal release efficiency. HTC at 180, 215 and 250 °C showed that P remained immobilized (> 75% of total P) in the HCs. More than 95% was present as inorganic P, and was the direct consequence of the double addition of iron salts in the wastewater treatment plant. Leaching experiments in 2.5 M acid solutions showed that a near complete release of P could be achieved in HCs, while it was only incomplete in SS (up to 85%). Lower acid concentrations were ineffective for total P recovery. Treatment temperature exceeding 180 °C however decreased P release rates, such that total removal took at least 2 h of reaction time instead of a few minutes. On the other hand, acid leaching transferred more than 70% of iron, manganese, copper and zinc into the leachate, necessitating a post-treatment purification process. This work therefore reveals that HC produced at low HTC temperatures could offer promising avenues for time- and energy-efficient P recovery from SS. [ABSTRACT FROM AUTHOR]

Welders are daily exposed to various levels of welding fumes containing several metals. This exposure can lead to an increased risk for different health effects which serves as a driving force to develop new methods that generate less toxic fumes. The aim of this study was to explore the role of released metals for welding particle-induced toxicity and to test the hypothesis that a reduction of Cr(VI) in welding fumes results in less toxicity by comparing the welding fume particles of optimized Cr(VI)-reduced flux-cored wires (FCWs) to standard FCWs. The welding particles were thoroughly characterized, and toxicity (cell viability, DNA damage and inflammation) was assessed following exposure to welding particles as well as their released metal fraction using cultured human bronchial epithelial cells (HBEC-3kt, 5–100 µg/mL) and human monocyte-derived macrophages (THP-1, 10–50 µg/mL). The results showed that all Cr was released as Cr(VI) for welding particles generated using standard FCWs whereas only minor levels (< 3% of total Cr) were released from the newly developed FCWs. Furthermore, the new FCWs were considerably less cytotoxic and did not cause any DNA damage in the doses tested. For the standard FCWs, the Cr(VI) released in cell media seemed to explain a large part of the cytotoxicity and DNA damage. In contrast, all particles caused rather similar inflammatory effects suggesting different underlying mechanisms. Taken together, this study suggests a potential benefit of substituting standard FCWs with Cr(VI)-reduced wires to achieve less toxic welding fumes and thus reduced risks for welders. [ABSTRACT FROM AUTHOR]

Cyclic voltammetry (CV) is expected to cause changes in the biocathode composition, especially when using low scan rates. A recent finding stated that CV triggered further biocatalytic activity in microbial electrosynthesis systems (MES), leading to the aim of our study: to investigate the invasiveness of CV on MES. The present study confirms that a CO2 elongation MES biocathode composition changes during and right after the CV. Oxidation peaks differ over repeated CV‐cycles while metal compounds and biomass were released in the biocatholyte. After CV, the current increased temporarily for up to 20 days and the metal compounds decreased from the biocatholyte solution. Further, the sole short application of open cell voltage was shown to shortly increase the current. Evidently CV affects the studied biocathode, which complicates the use of CV as an analysis technique in MESs. However, the positive effect CV has on biocathode current density may provide methods to boost reactor performance and maintain productivity. [ABSTRACT FROM AUTHOR]

The effect of austenitising heat treatment on the microstructure, hardness and metal release of the nitrogen bearing, martensitic stainless steel 420U6 was investigated. The heat treatment was carried out at temperatures between 950 to 1,150∘C with a holding time between 30 to 120min, followed by air cooling. The quenched microstructures observed by a scanning electron microscope indicated that by increasing the austenitising temperature and holding time, the number of carbides decreases while the grain size and the amount of retained austenite increases. For a given holding time, the hardness increases to a peak and then decreases continuously with the increase of temperature. The metal release test, according to the GB 4806.9-2016 standard, reveals that the metal release concentration is highly affected by the austenitising temperature. The parameters of the austenitising heat treatment, which can achieve the optimum combination of hardness and metal release, were obtained.

In this study, we introduce a simple screening method to predict the metal release from biostabilized wastes as a function of the total organic carbon (TOC) content of the sample. The method relies on a model that simulates the release of dissolved organic carbon (DOC) as a function of the applied liquid to solid (L/S) ratio. The metal release is then estimated using generic empirical DOC to metal correlation coefficients (KDOC,Me) extrapolated from the literature. Specifically, the results of leaching tests carried out on different types of biowastes and biostabilized wastes were used to calculate the upper and lower KDOC,Me values that can be expected for common metals of concern (Al, Ba, Cr, Cu, Mo, Ni, Pb, V, and Zn). The statistical analysis of the estimated empirical coefficients highlighted that for most of the investigated metals, the adoption of generic DOC to metal correlation coefficients introduces relatively low uncertainties. The quartiles ratio (QR calculated as the ratio of third and first quartile) of the KDOC,Me coefficients extrapolated from the literature was indeed below 3 for Cu, Ni, and Zn and below 5 for Al, Ba, Cr, Pb, and V. Only for Mo, the QR was around 10 indicating that for this element, DOC can be a poor indicator of the release expected as a function of the applied L/S. Furthermore, by performing a sensitivity analysis, we found that the experimental conditions only slightly influence the metals release predicted by the model. Based on this evidence, simple nomograms that estimate the cumulative metal release in percolation column tests as a function of the applied L/S are provided. Furthermore, a simple equation that predicts the cumulative metal release expected at L/S of 10 L/kg is presented. The application of the latter to the results of percolation column tests carried out on 8 mechanical biological treatment (MBT) waste samples highlighted that the predicted metals release was close to the measured values with deviations within a factor of 5 for all the investigated metals. [ABSTRACT FROM AUTHOR]

Copper, diagnostics, dimethylglyoxime, metal release, nickel, nickel allergy, DMG Keywords: copper; diagnostics; dimethylglyoxime; DMG; metal release; nickel; nickel allergy EN copper diagnostics dimethylglyoxime DMG metal release nickel nickel allergy 431 433 3 04/14/22 20220501 NES 220501 The dimethylglyoxime (DMG) spot test is widely used to screen for nickel release that may cause allergic nickel contact dermatitis in allergic individuals. The tested earring with nickel release of 0.87 g/cm SB 2 sb /week was expected to become DMG spot test positive, but this result was possibly masked due to the brown discolouration caused by a DMG-copper reaction (Figure 2). [Extracted from the article]

Background: Metalworkers are said to have heavy exposure to metals, but the amount of released metal ions from alloys and deposition on the hands is unknown. Objective: To analyze nickel, cobalt, and chromium in vitro release to the artificial sweat from nails and wire made of different alloys, and to test metal deposition on the fingers of metalworkers. Material and Methods: Six different samples of nails and wire were kept in artificial sweat for 24 hours and one week, respectively. The metal release was determined by atomic absorption spectrometry (AAS). Eighty‐eight consecutive metal plant workers immersed their index fingers and thumbs in separate laboratory tubes filled with deionized water for 2 minutes. The sample analysis for metals was carried out with an inductively coupled plasma mass spectrometer (ICP‐MS). Results: The average released concentration of Ni was 0.0012 μg/cm2, for Co it was 0.0007 μg/cm2, and for Cr 0.0037 μg/cm2 after 24 hours and 0.0135, 0.0029, and 0.0042 μg/cm2, respectively, after 1 week. There was a statistically significant increase in released concentration of Ni during one week: 0.0012 μg/cm2 vs 0.0135 μg/cm2 (P =.04). Medians of the detected Co amount on fingers reflected a statistically significant difference between workplaces: 0.004 μg/cm2 for metalworkers vs 0.001 μg/cm2 for office staff (P =.04). Conclusion: Nickel (Ni), cobalt (Co), and chromium (Cr) can be released in different concentrations from nails and wire. Detected Ni and Cr levels can elicit dermatitis in already sensitized patients. Co can be extracted from alloys even if not mentioned on material safety data sheets. The finger immersion technique was used for cobalt and chromium detection on fingers for the first time. [ABSTRACT FROM AUTHOR]

Cobalt-chromium-molybdenum (CoCrMo) alloys are common wear-exposed biomedical alloys and are manufactured in multiple ways, increasingly using additive manufacturing processes such as laser powder bed fusion (LPBF). Here, we investigate the effect of proteins and the manufacturing process (wrought vs LPBF) and building orientation (LPBF- XY and XZ ) on the corrosion, metal release, tribocorrosion, and surface oxide composition by means of electrochemical, mechanical, microscopic, diffractive, and spectroscopic methods. The study was conducted at pH 7.3 in 5 g/L NaCl and 5 mM 2-( N -morpholino) ethanesulfonic acid (MES) buffer, which was found to be necessary to avoid metal phosphate and metal-protein aggregate precipitation. The effect of 10 g/L bovine serum albumin (BSA) and 2.5 g/L fibrinogen (Fbn) was studied. BSA and Fbn strongly enhanced the release of Co, Cr, and Mo and slightly enhanced the corrosion (still in the passive domain) for all CoCrMo alloys and most for LPBF- XZ , followed by LPBF- XY and the wrought CoCrMo. BSA and Fbn, most pronounced when combined, significantly decreased the coefficient of friction due to lubrication, the wear track width and severity of the wear mechanism, and the tribocorrosion for all alloys, with no clear effect of the manufacturing type. The wear track area was significantly more oxidized than the area outside of the wear track. In the reference solution without proteins, a strong Mo oxidation in the wear track surface oxide was indicative of a pH decrease and cell separation of the anodic and cathodic areas. This effect was absent in the presence of the proteins.

Hazard classification of metal alloys is today generally based on their bulk content, an approach that seldom reflects the extent of metal release for a given environment. Such information can instead be achieved via bioelution testing under simulated physiological conditions. The use of bioelution data instead of bulk contents would hence refine the current hazard classification of alloys and enable grouping. Bioelution data have been generated for nickel (Ni) and cobalt (Co) released from several stainless steel grades, one low-alloyed steel, and Ni and Co metals in synthetic sweat, saliva and gastric fluid, for exposure periods from 2 to 168 h. All stainless steel grades with bulk contents of 0.11–10 wt% Ni and 0.019–0.24 wt% Co released lower amounts of Ni (up to 400-fold) and Co (up to 300-fold) than did the low-alloyed steel (bulk content: 0.034% Ni, 0.015% Co). They further showed a relative bioaccessibility of Ni and Co considerably less than 1, while the opposite was the case for the low-alloyed steel. Surface oxide- and electrochemical corrosion investigations explained these findings in terms of the high passivity of the stainless steels related to the Cr(III)-rich surface oxide that readily adapted to the fluid acidity and chemistry.

Complex metal oxides (CMOs) are used broadly in applications including electroreactive forms found in lithium-ion battery technology. Computational chemistry can provide unique information about how the properties of CMO cathode materials change in response to changes in stoichiometry, for example, changes of the lithium (Li) content during the charge–discharge cycle of the battery. However, this is difficult to measure experimentally due to the small cross-sectional area of the cations. Outside of operational conditions, the Li content can influence the transformations of the CMO when exposed to the environment. For example, metal release from CMOs in aqueous settings has been identified as a cross-cutting mechanism important to CMO degradation. Computational studies investigating metal release from CMOs show that the thermodynamics depend on the oxidation states of lattice cations, which is expected to vary with the lithium content. In this work, computational studies track changes in metal release trends as a function of Li content in Lix(Ni1/3Mn1/3Co1/3)O2 (NMC). The resulting dataset is used to construct a random forest tree (RFT) machine learning (ML) model. A modeling challenge in delithiation studies is the large configurational space to sample. Through investigating multiple configurations at each lithium fraction, we find structural features associated with favorable energies to chemically guide the identification of relevant structures and adequately predict voltage values.

Nickel (Ni) and cobalt (Co) release from chromium-alloy powders (different stainless steels and a nickel-based Inconel alloy) compared with Ni and Co metal powders was investigated at simulated human exposure scenarios (ingestion, skin contact, and inhalation) between 2 and 168 h. All investigated powders consisted of particles sized within the respirable range. The powder particles and their surface reactivity were studied by means of nitrogen adsorption and electrochemical, spectroscopic (X-ray photoelectron spectroscopy and atomic absorption spectroscopy), light scattering, and microscopic techniques. The release of both Ni and Co was highest in the acidic and complexing fluids simulating the gastric environment and an inhalation scenario of small powders (artificial lysosomal fluid). Relatively high corrosion resistance and lower levels of released Ni and Co were observed in all fluids for all alloy powders compared with the corresponding pure metals. The extent of released metals was low for powders with a passive surface oxide. This study strongly emphasizes the importance of considering alloying effects in toxicological classification and/or regulation of Ni and Co in alloys and metals. [ABSTRACT FROM AUTHOR]

Increasing cases of adverse local tissue reactions (ALTRs) associated with metal release have been observed in patients with metal‐on‐highly crosslinked polyethylene (MoP) hip implants, the most common design in total hip replacements. Studies have demonstrated the metal release from fretting corrosion at the head–neck junction, but rarely investigated tribocorrosion associated metal release at articulating surfaces in MoP hip implants. The objective of this study is to investigate both tribocorrosion at the articulating surfaces and fretting corrosion at the head–neck junction in CoCrMo femoral heads, as well as their association with metal species released in periprosthetic tissues and body fluids in MoP hip systems. Twenty‐three patients with ALTRs associated with MoP implants were included. Systematic analyses were performed on the wear damage in articulation, corrosion at the head–neck junction and their correlation with degradation products observed in synovial fluid, periprosthetic tissues, and serum. Results showed that tribocorrosion at the articulating surfaces contributed to the elevated concentration of both Co and Cr ions in serum, while fretting corrosion at the head–neck junction mainly released Co ions to serum. Both tribocorrosion at the articulating surfaces and fretting corrosion at the head–neck junction released particles rich in chromium and phosphate, the dominant particles found in synovial fluids and tissues. This study provides strong evidence that tribocorrosion at the articulating surfaces in MoP hip implants could result in significant metal release. This information should be taken into account when studying the mechanisms of ALTRs and developing strategies of preventing metal release in total hip replacements. [ABSTRACT FROM AUTHOR]

The aim of this study was to devise a modification of a temporary anchorage device (TAD) by coating titanium mini screw implants with yttrium stabilized zirconia and to evaluate the insertion torque and surface integrity of it. Five titanium implants (Absoanchor, Dentos, South Korea) from each of the four groups comprising of 6 SH 13-08, 6 SH 13 -10 cylindrical and 6 SH 1312-08, 6 SH 1312-10 tapered mini screw implants were selected to be in the experimental group (Zr Ti) of implants, wherein they were coated with yttrium stabilised zirconia using a RF/DC magnetron sputtering unit. One mini screw implant from each of the four groups remained without coating to serve as control (Ti). After the coating of the titanium mini screw implants, scanning electron microscope (SEM) study was performed to evaluate the thickness and uniformity of the coating obtained. The insertion torque of all implants were evaluated by inserting the implant into bone sample using a manual torque wrench (ADIN). The implants were retrieved from the bone sample and a post insertion SEM study was performed to evaluate any changes in the surface of the Zr-Ti and Ti implants. X-ray diffraction (XRD) analysis was done to confirm the presence of Zirconia in the implants from the experimental group. There was no statistically significant difference between the insertion torque for the zirconia coated mini screw implants and the titanium mini screw implants, where the P value < 0.05 was considered as statistically significant. The values for insertion torque for Zr Ti cylindrical group of 8 mm length ranged from 19-20 N-cm and that for the tapered group of 8 mm length ranged from 15-17 N-cm. The insertion torque for the Zr Ti tapered group of 8 mm ranged from 21-22 N-cm and that of the tapered group ranged from 16-18 N-cm.The insertion torque values for the Ti cylindrical implant for length of 8 mm was 20 N-cm and 21 N-cm for length of 10 mm. The insertion torque values for the Ti tapered implant was 15N-cm for 8 mm length and 16N-cm for 10 mm length. The Zirconia coating on the Titanium mini screw implants was of 2.6 µm in thickness. There was no statistically significant difference in the insertion torque of the Zirconia coated mini screw implants and the non-coated titanium mini screw implants which retained their structural integrity. • Zirconia coated titanium mini screw implants were developed. • Maximum insertion torque and surface characteristics were evaluated. • There observed no change in surface thickness of 2.6 μ between as-received and retrieved zirconia coating over titanium miniscrews. • Maximum insertion torque was higher with cylindrical than tapered ones for both 8 and 10 mm length mini screws. [ABSTRACT FROM AUTHOR]

Stormwater treatment systems such as biofilters could intercept and remove pollutants from contaminated runoff in wildfire-affected areas, ensuring the protection of water quality downstream. However, the deposition of wildfire residues such as ash and black carbon onto biofilters could potentially impair their stormwater treatment functions. Yet, whether and how wildfire residue deposition could affect biofilter functions is unknown. This study examines the impact of wildfire residue deposition on biofilter infiltration and pollutant removal capacities. Exposure to wildfire residues decreased the infiltration capacity based on the amount of wildfire deposited. Wildfire residues accumulated at the top layer of the biofilter, forming a cake layer, but scraping this layer restored the infiltration capacity. While the deposition of wildfire residues slightly changed the pore water geochemistry, it did not significantly alter the removal of metals and E. coli. Although wildfire residues leached some metals into pore water within the simulated root zone, the leached metals were effectively removed by the compost present in the filter media. Collectively, these results indicate that biofilters downstream of wildfire-prone areas could remain resilient or functional and protect downstream water quality if deposited ash is periodically scraped to restore any loss of infiltration capacity following wildfire residue deposition. [Display omitted] • Deposited wildfire residues formed a cake layer that could clog biofilters. • Removing the cake layer can restore biofilter infiltration capacity. • Exposure to wildfire residues did not affect pore water quality parameters. • Deposited residues did not significantly affect the removal of metals, and E. coli. • Deposited wildfire residues did not release metals into treated effluent. [ABSTRACT FROM AUTHOR]

The release of certain metallic constituents within some dental implants could contribute to peri-implantitis and mucositis. While the release rate into surrounding bones and tissues may be dependent on the biocompatibility of dental materials and their designs, the patient's oral hygiene and even the prevalence of certain resident oral bacteria may also affect the service lives of these dental implants by altering their gross corrosion rates. In this study, the levels of Fe, Cr, and Ni released during microbiologically induced intergranular corrosion of medical grade 316L stainless-steel dental material are measured across defined culture durations. Porphyromonas gingivalis , a prominent component of the oral microbiome known to associate with periodontitis and peri-implantitis, is the test bacterium in this study. From the evidence obtained from electrochemical and surface investigations in artificial salivary culture media, dental substates corroded significantly upon maturation of bacterial growth. Corrosion was accompanied by higher levels of metal ion release at extended culture duration. About 1.5 and 9.5 μg/cm2 of Ni and Cr were leached from the metal alloy after a 30-day exposure to the bacterial culture relative to the control; Fe was released 30 times more in the former. This study highlights how oral metal contact influences the corrosion of metallic dental implants (e.g., stainless-steel crowns) in patients infected by certain resident oral bacterium. • Higher amounts of metallic leachants released from dental substrates in salivary culture. • Higher levels of Fe were observed in the culture compared to Ni and Cr. • The above trend continued with and without bacterial inoculation. • Bacterial growth accelerated MIC accompanied by increased j corr and lowered R p. • Intergranular corrosion intensified with evolving volatile sulfur compounds. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the resistance to impingement damage of three different artificially aged UHMWPE materials used for total hip joint replacement. The results obtained can be used as a basis for an acceptance criterion for testing according to ASTM F2582-20. Three different polyethylene liner materials, standard polyethylene (UHMWPE), moderately crosslinked (XLPE) and vitamin E stabilized crosslinked (XLPE-VE) polyethylene of the same design and manufacturer were tested up to one million impingement cycles according to ASTM F2582-20. The liners were artificially oxygen aged for two and three weeks according to ASTM F2003-02. The wear volumes of the liner, acetabular shells, and hip endoprosthesis stems were determined. Each of the six impingement test groups consisted of three samples. For each test group, a reference group was subjected to the same conditioning and loading conditions but without impingement between the hip stem and the liner. The force needed to disassemble the liner from the acetabular shell (push-out force) was determined according to ASTM F1820-22 for the test and the reference groups. XLPE and XLPE-VE polyethylene groups showed less impingement wear when compared to the standard UHMWPE material. Similarly, the protective function of the liner against direct metal-on-metal contact was greater, resulting in less wear on the acetabular shell and the stem neck. The three weeks aged standard UHMWPE group showed early onset of fatigue delamination wear. The push-out values remained unchanged for all XLPE liners and the 3-week aged XLPE-VE liners. The aged UHMWPE liners showed low push-out strength due to component shrinkage caused by aging in combination with the tapered fixation used for this specific design. The largest polyethylene wear volume measured of XLPE and XLPE-VE polyethylene aged for two and three weeks was 15.05 mm³ (SD 0.56 mm³). The corresponding metal wear volume was 1.23 mm³ (SD 0.19 mm³) for the acetabular cup and 1.33 mm³ (SD 0.20 mm³) for the stem neck. Those values can support the definition of an acceptance criteria for impingement testing. The results of the push-out test required by ASTM F2582-20 should be evaluated with respect to geometry changes caused by aging. The protective effect of the polyethylene liner against metal-on-metal contact should be considered in the implant design phase in order to avoid implant failure due to metal debris. [Display omitted] • Cross-linked polyethylene has better wear resistance under impingement conditions than standard polyethylene. • Artificial aging did not deteriorate the impingement resistance of the crosslinked polyethylene. • Three weeks of artificial aging of standard UHMWPE results in early onset of fatigue delamination wear. • Progressive impingement wear can lead to metal abrasion. [ABSTRACT FROM AUTHOR]

Application of pulsed electric fields (PEFs) is an alternative treatment to thermal pasteurization of liquid foods, which inactivates microorganisms without degrading flavor, texture, and nutrients compared to other conventional technologies. This article scrutinizes the applicability of PEF processing of carbonated beer using a titanium electrode based sealed processing chamber that provides not only effective use of the highest electric field but also eliminates edge effects, and at the same time reduces turbulence by providing steady and uniform flow of the fluid under treatment. The release of metal ions during PEF processing is evaluated by using inductively coupled plasma atomic emission spectrometry (ICP-AES). As metal ions directly affect the organoleptic properties of beer, a sensory evaluation is conducted with the panelists comprised of brewing experts. It has been found that the released amounts of metal ions are lower than the detection levels of ICP-AES, and much lower than what is accepted in consumable foods (<2 parts per billion). Supporting the metal analysis data, the sensory panel also reported nonoff flavors in the PEF-processed beer. The treated and untreated beer samples are aged at 5 °C, 22 °C, and 34 °C for ten days. The shelf-life analysis is conducted for PEF-treated and untreated beer samples. The organoleptic property profile of the beer treated at 4 kV by PEF shows the potential of extending shelf life at least for 90 days. In addition, analytical indicators like the deterioration of trans-iso-α-acids confirm no chemical changes in beer before and after PEF treatment under the conditions studied. [ABSTRACT FROM AUTHOR]

Millions of people in the world perform welding as their primary occupation resulting in exposure to metal-containing nanoparticles in the fumes generated. Even though health effects including airway diseases are well-known, there is currently a lack of studies investigating how different welding set-ups and conditions affect the toxicity of generated nanoparticles of the welding fume. The aim of this study was to investigate the toxicity of nine types of welding fume particles generated via active gas shielded metal arc welding (GMAW) of chromium-containing stainless steel under different conditions and, furthermore, to correlate the toxicity to the particle characteristics. Toxicological endpoints investigated were generation of reactive oxygen species (ROS), cytotoxicity, genotoxicity and activation of ToxTracker reporter cell lines. The results clearly underline that the choice of filler material has a large influence on the toxic potential. Fume particles generated by welding with the tested flux-cored wire (FCW) were found to be more cytotoxic compared to particles generated by welding with solid wire or metal-cored wire (MCW). FCW fume particles were also the most potent in causing ROS and DNA damage and they furthermore activated reporters related to DNA double- strand breaks and p53 signaling. Interestingly, the FCW fume particles were the most soluble in PBS, releasing more chromium in the hexavalent form and manganese compared to the other fumes. These results emphasize the importance of solubility of different metal constituents of the fume particles, rather than the total metal content, for their acute toxic potential. [ABSTRACT FROM AUTHOR]

Nickel (Ni) and cobalt (Co) are the most common metal allergens upon skin contact at occupational settings and during consumer handling of metals and alloys. A standardized test (EN, 1811) exists to assess Ni release from articles of metals and alloys in massive forms intended for direct and prolonged skin contact, but no corresponding test exists for other materials such as powders or massive forms of alloys placed on the market or to determine the release of Co, for which only limited data is available. Differences in Ni and Co release from massive forms of a range of common stainless steels and some high-alloyed grades compared to Ni and Co metals were therefore assessed in artificial sweat for 1 week at 30 °C according to EN 1811. A comparable modified test procedure was elaborated and used for powders and some selected massive alloys. All alloys investigated released significantly less amount of Ni (100–5000-fold) and Co (200–400,000-fold) compared with Ni and Co metal, respectively. Almost all alloys showed a lower bioaccessible concentration (0.007–6.8 wt% Ni and 0.00003–0.6 wt% Co) when compared to corresponding bulk alloy contents (0.1–53 wt% Ni, 0.02–65 wt% Co). Observed differences are, among other factors, related to differences in bulk composition and to surface oxide characteristics. For the powders, less Ni and Co were released per surface area, but more per mass, compared to the corresponding massive forms. Image 1 • Bioaccessibility test of Co and Ni released from metals/alloys in artificial sweat. • Modification of the EN 1811 standard to assess bioaccessible Ni and Co from powders. • Ni release from alloys (0.1–53 wt% Ni) 100–5000 times lower than from Ni metal. • Co release from alloys (0.02–65 wt% Co) 200–400,000 times lower than from Co metal. • Less metal release per surface area, but higher per mass, for powders vs. massives. [ABSTRACT FROM AUTHOR]

Abstract Stainless steel is an important transport and processing contact material for bovine milk and dairy products. Release (migration) of metals, ions, complexes or wear debris/particles, and metal-induced protein aggregation in such environments are hence important to consider both from a corrosion and food safety perspective. This study aims on investigating the release of iron (Fe), chromium (Cr), and nickel (Ni) from AISI 316L stainless steel in contact with whey protein solutions relevant for protein drinks, and on how the whey proteins are influenced by stirring with a magnetic stir bar and metal release. Mechanistic insight is gained by parallel investigations of metal release from two reference non-protein containing solutions, a metal-complexing (citrate-containing) simulated milk solution (SMS) and a low complexing phosphate buffered saline solution (PBS). All immersion exposures were conducted at pH 6.8 for 0.5, 4, 24 and 48 h at room temperature at static and stirring conditions. All solutions and samples were investigated using different chemical, spectroscopic, microscopic, and electrochemical methods. Significantly higher amounts of Fe, Cr, and Ni were released into the whey protein solution (80 g/L) as compared to SMS and PBS. Strong enrichment of Cr in the surface oxide and reduction of the surface oxide thickness were associated with a higher amount of Ni release in the metal-complexing solutions (SMS and whey protein) compared with PBS. Stirring conditions resulted in higher amounts of metal release, enrichment of Cr in the surface oxide, and clear signs of wear of the 316L surface in all solutions compared to static conditions. The wear mechanism in the whey protein solution was different as compared to corresponding processes in SMS and PBS, involving an etching-like process and larger-sized wear debris. Electrochemical measurements at static conditions confirmed observed differences between the solutions, with the lowest corrosion resistance observed for coupons exposed in the whey protein solution, followed by SMS and PBS. Released metals in solution from the 316L coupons in contact with the whey protein solution resulted in enhanced rates of protein aggregation and precipitation of protein aggregates from solution. Further studies should be made to investigate other relevant test conditions and assess toxicological risks. Highlights • Stainless steel – whey protein interactions at static and stirred conditions. • Increased metal release from stainless steel in the presence of whey proteins. • Metal-complexation suggested to contribute to combined degradation mechanisms. • Highest corrosion, metal release, and wear when stirred with whey proteins. • Released metal ions or wear debris/particles induced whey protein aggregation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Long-term atmospheric corrosion and metal release studies of Sn-bronze and Cu metal at urban and marine environments. • The presence of Sn oxides in the native Cu 2 O rich surface oxide of Sn-bronze improves its barrier properties. • Sn alloying reduces the corrosion rate of Sn bronze at urban conditions. • No beneficial corrosion effects of Sn alloying at chloride-rich marine conditions. • Metal release marginally influenced by Sn alloying. Abstract The role of Sn on the atmospheric corrosion performance of binary Cu-Sn bronze alloys (4–6 wt.% Sn) compared with Cu metal used in outdoor architecture is elucidated in terms of microstructure, native surface oxide composition, patina evolution, corrosion rates, appearance and metal release. Results are presented for non-exposed surfaces and surfaces exposed at different urban and marine sites in Europe up to 5 years and based on multi-analytical findings from microscopic, spectroscopic, electrochemical and chemical investigations. Alloying influenced the corrosion, aesthetic appearance and patina evolution, differently for urban and marine sites, whereas no effects were observed on the release pattern. [ABSTRACT FROM AUTHOR]

Abstract The impact of mechanical disturbance and oxygen induced acidification on the concentration and size fractionation of the 12 metal(loid)s As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Tl, V and the polyatomic nonmetals C, P and S in the pore water was studied. Using the meso profiling and sampling system (messy) 12 pore water depth profiles were sampled from two incubation experiments undertaken in parallel, which were both mechanically disturbed in the lab and subsequently exposed to a different air supply. In parallel to the low invasive, automated sampling process the redox potential, the pH value and the O 2 concentration were detected. Simultaneous quantification of all analytes by inductively coupled plasma-triple quad-mass spectrometry in the two different size classes dissolved (<0.45 μm) and colloidal (0.45–16 μm) showed: i) the predominant influence of the pH on the mobility of metals; ii) the mobility of metalloids was strongly impacted by the mechanical disturbance; and iii) the colloidal release is less important except for Fe, P, and Ni. Graphical abstract Unlabelled Image Highlights • Mobility of 12 metal(loid)s, C, P and S, during disturbances at the SWI was studied • Except for As, Sb, V, mobility of all analytes was more affected by acidification • Mechanical disturbance promoted the mobility of As, Sb, and V • Except for Ni, colloids (0.45–16 μm) were not significant for metal(loid)s mobility • All analytes were quantified by ICP-QQQ-MS in a single run multi-element approach [ABSTRACT FROM AUTHOR]

This prospective study examined the content of metals released from total joint arthroplasty into joint fluid, whole blood and periprosthetic tissues. We determined the levels of Ti, V, Nb, Co, Cr, and Mo, using inductively coupled plasma mass spectrometry, in samples from patients who underwent reoperation of total hip or knee arthroplasty. All of the patients (n = 117) included in the study had either metal on polyethylene or ceramic on polyethylene‐bearing pairs. First, our results conclusively showed that the majority of released metals were deposited in periprosthetic tissues. In this context, the bloodstream turned out to be an ineffective biomarker of the effects occurring in local tissues. Second, there was a clear time‐dependent nature of metallic accumulation. Based on our extensive dataset, we found significantly elevated levels of the released metals in joint fluid and periprosthetic tissues originating from loosened implants compared to stable ones, as well as recognizable differences between the groups with stable implants and aseptic loosening. Finally, it was proved that the concentrations of metals decreased dependent on the distance of the tissue from the implant. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 454–462, 2019. [ABSTRACT FROM AUTHOR]

• Effect of surface finish on corrosion and metal release from Ti6Al4V studied. • Ti6Al4V was produced by laser powder bed fusion using biomedical protocols. • Nitric acid passivation had a negligible effect on metal release and corrosion. • Effect of surface finish (sandblasted, polished) explained by true surface area. • More proteins were adsorbed on rough (sandblasted) surfaces. The biomedical titanium alloy Ti6Al4V has excellent corrosion resistance and biocompatibility and is, therefore, widely used in orthopedic and orthodontic implants. Biomedical implants are increasingly fabricated by additive manufacturing, such as laser powder bed fusion (LPBF). These manufacturing protocols often include sandblasting, surface finish, and passivation. This study aims to investigate the effect of different surface finishes and the commonly used ASTM F86–13 nitric acid passivation for LPBF Ti6Al4V on its corrosion resistance, metal release, and surface changes in benign (bovine serum albumin in a pH 7.4 buffer) and harsh (hydrochloric acid at pH 1.5) solutions using various electrochemical and spectroscopic techniques. Electrochemical, solution and surface analysis showed an insignificant effect of passivation. Smooth surfaces exhibited a slightly better corrosion resistance than rough surfaces due to a 10–20 % smaller true surface area and lower protein adsorption. Implanted ceramic beads from the sandblasting procedure remained on the surface even after the mirror-polishing and passivation procedures. [Display omitted] [ABSTRACT FROM AUTHOR]

Despite being corrosion-resistant, plastic potable water pipes might accumulate heavy metals on their surface if they convey metal-contaminated tap water. This study examined the influence of water pH and flow conditions on lead (Pb) release from new and biofilm-laden potable water pipes to provide insights regarding decontamination. For this purpose, biofilms were grown onto new crosslinked polyethylene (PEX-A), high-density polyethylene (HDPE), and copper pipes for three months. Lead was then deposited onto the new and biofilm-laden pipes through 5 d exposure experiments under flow conditions. After that, lead release experiments were conducted by exposing the lead-accumulated pipes to lead-free synthetic tap water for 5 d, under both stagnant and water flow conditions. The metal accumulation study showed no significant difference in lead uptake by new pipes and their biofilm-laden counterparts under flow conditions. This could be attributed to the detachment of biofilms that have accumulated lead as water flows through the pipes. Water flow conditions significantly influenced the lead release from new and biofilm-laden water pipes. A lower water pH of 5.0 increased the release of lead from plastic pipes into the contact water, compared to pH 6.0 and 7.8. The greatest percentage of lead was released from biofilm-laden HDPE pipes (5.3%, 120 h) compared to biofilm-laden copper pipes (3.9%, 6 h) and PEX-A (3.7%, 120 h) and after exposure to lead-free synthetic tap water at pH 5.0, under stagnant conditions. On the other hand, under water flow conditions, the greatest lead release was found for new PEX-A pipes (4.4%, 120 h), new HDPE pipes (2.7%, 120 h), and biofilm-laden copper pipes (3.7%, 2 h). [Display omitted] • Pb depositions on new and biofilm-laden water pipes were not different under flow conditions. • The lower pH promoted lead release from new plastic and copper potable water pipes. • Biofilm-laden plastic pipes released more Pb than new pipes under stagnant conditions. [ABSTRACT FROM AUTHOR]

Schizophyllum commune is a filamentous basidiomycete which can degrade complex organic macromolecules like lignin by the secretion of a large repertoire of enzymes. One of these white rot enzymes, laccase, exhibits a broad substrate specificity and is able to oxidize a variety of substances including carbonaceous rocks. To investigate the role of laccase in bioweathering, laccase gene lcc2 was overexpressed, and the influence on weathering of black slate, originating from a former alum mine in Schmiedefeld, Germany, was examined. The metal release from the rock material was enhanced, associated with a partial metal accumulation into the mycelium. A sequestration of metals could be shown with fluorescent staining methods, and an accumulation of Zn, Cd, and Pb was visualized in different cell organelles. Additionally, we could show an increased metal resistance of the laccase overexpressing strain. [ABSTRACT FROM AUTHOR]

The sulphide-rich mine wastes accumulated in tailing dumps of La Concordia Mine (Puna of Argentina) have been exposed to the weathering action for more than 30 years. Since then, a series of redox reactions have triggered the generation of a highly acidic drainage -rich in dissolved metals-that drains into the La Concordia creek. The extent of metal and acid release in the site was analysed through field surveys and laboratory experiments. Static tests were conducted in order to predict the potential of the sulphidic wastes to produce acid, while Cu-, Zn-, Fe- and Pb-bearing phases present in the wastes were identified by XRD, SEM/EDS analysis and sequential extraction procedures. Finally, the release of these metals during sediment-water interaction was assessed in batch experiments carried out in a period of nearly two years. Field surveys indicate that the prolonged alteration of the mine wastes led to elevated electrical conductivity, pH values lower than 4 and metal concentrations that exceed the guide values for drinking water in the La Concordia stream regardless of the dominating hydrological conditions. The highly soluble Fe and Mg (hydrous)sulphates that form salt crusts on the tailings surfaces and the riverbed sediments play an important role in the control of metal mobility, as they rapidly dissolve in contact with water releasing Fe, but also Cu and Zn which are scavenged by such minerals. Another important proportion of the analysed metals is adsorbed onto Fe (hydr)oxides or form less soluble hydroxysulfates. Metals present in these phases are released to water more slowly, thus representing a potential long term source of heavy metal pollution. The obtained results are a contribution to the understanding of long term metal transformations and mobility in mine waste-impacted sites. [ABSTRACT FROM AUTHOR]

Abstract: Small indium (In) additions up to 5 wt % to the beta‐type Ti‐40Nb alloy effectively improve its mechanical biofunctionality. The impact on its biocompatibility is addressed in this work. Comparative electrochemical polarization studies and inductively coupled plasma optical emission spectrometry analyses were conducted in Tris‐buffered saline (on the basis of 150 mM NaCl) with pH 7.6 and 2.0 at 310 ± 1 K with Ti‐6Al‐4V as reference. The metal ion releases from beta‐type alloys were generally very low, for example, those of In3+ ions from (Ti‐40Nb)‐4In specimens were below 6 × 10−7 mmol/cm2. X‐ray photoelectron spectroscopy revealed the passivation mainly by Ti‐ and Nb‐oxides with traces of In‐oxides as the dominating surface process. In vitro studies demonstrate a better human bone marrow stromal cells (hBMSC) activity on the beta‐type alloys in comparison to CP‐Ti (grade 2), which is mainly due to their high Nb content. At 24 h after seeding on (Ti‐40Nb)‐4In the metabolic activity of hBMSC was 1.5‐fold higher and after 11 days, the tissue non‐specific alkaline phosphatase activity was 1.8‐fold higher relative to values for CP‐Ti. Surface treatments, like chemical etching or plasma oxidation, change the surface topography and the thickness and composition of the oxide layers, but they are not effective in further improving the cell response. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1686–1697, 2018. [ABSTRACT FROM AUTHOR]

The potential release of toxic metals from damaged emerging photovoltaic (PV) cells has raised concerns about the safe use of these new types of PVs. In this study, this concern was addressed by analysing the life cycle toxicity of metals (cadmium, copper, lead, nickel, tin and zinc) that are commonly used in emerging PVs. In estimating the potential metal release, a new model that incorporates field conditions (crack size, time, and glass thickness) and physiochemical properties (diffusion coefficient and solubility product) was introduced. The results show that the use phase toxicity of copper and lead can be higher than the extraction phase toxicity. Thus, precautionary loss limits to manage toxic impacts from the use phase were proposed. Also, the toxicity from different layers of perovskite, copper zinc tin sulphide (CZTS), and quantum dot (QD) type of solar cells was compared. It was found that cadmium sulphide (compared to zinc oxide and tin oxide) and lead (II) sulphide (compared to lead (II) iodine and CZTS) were less toxic alternatives for the electron selective layer and light absorber, respectively. Finally, in comparing the toxic metal releases of the PVs to today's coal power plants, it was seen that the metal emissions from PVs are expected to be several times less than the emissions from coal. [ABSTRACT FROM AUTHOR]

The phosphorus (P) removal of five combinations of dual filters consisting of blast furnace slag (BFS), argon oxygen decarburisation slag (AOD) and electric arc furnace slag (EAF) was evaluated in column experiments with domestic waste water. The columns were fed with waste water for 24 days. The column with only EAF had the best P removal performance (above 93% throughout the experiment). The speciation of the bound P was evaluated by P K-edge X-ray absorption near-edge structure (XANES) spectroscopy. In all five columns, the main P species of the slag packed in the outlet chamber was amorphous calcium phosphate (ACP). In samples from the inlet chambers, the contributions from crystalline Ca phosphates, P adsorbed on gibbsite and P adsorbed on ferrihydrite were usually much greater, suggesting a shift of P removal mechanism as the waste water travelled from the inlet to the outlet. The results provide strong evidence that P was predominantly removed by the slags through the formation of ACP. However, as the pH decreased with time due to the progressively lower dissolution of alkaline silicate minerals from the slag, the ACP was rendered unstable and hence redissolved, changing the P speciation. It is suggested that this process strongly affected the lifespan of the slag filters. Of the slags examined, EAF slag had the best P removal characteristics and BFS the worst, which probably reflected different dissolution rates of alkaline silicates in the slags. [ABSTRACT FROM AUTHOR]

This manuscript evaluates the potential application of active nanocomposite films based on soy protein isolate (SPI)-montmorillonite (MMT)-clove essential oil (CEO) to the preservation of muscle fillets of bluefin tuna ( Thunnus thynnus ) during refrigerated storage, and furthermore analyzes whether the clay diffuses from the package to food. SPI films with: CEO (SPI-CEO), MMT (SPI-MMT), or both CEO and MMT (SPI-MMT-CEO), were prepared and used to cover tuna fillets during 17 days of storage at 2 °C. Polyethylene films were also used as control. Protein films nanoreinforced with 10 g MMT/100 g SPI and activated with CEO were able to decrease microbial growth (evaluated by TVBN and microorganism counts) and lipid autooxidation (evaluated according to the TBA index, FTIR and color parameters) of tuna fillets during the storage period studied. The presence of clay seemed to favor the release of the active principles of clove oil by prolonging its antimicrobial (especially effective to inhibit Pseudomonas spp.) and antioxidant activity over time without observing the diffusion of the clay's own metals (Si and Al) from the nanocomposite materials to the muscle of fish. These results are encouraging for the use of nanocomposite films in food packaging. [ABSTRACT FROM AUTHOR]