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The total arsenic mass fraction as well as the arsenic speciation were studied in four different mushroom species with inductively coupled plasma mass spectrometry and high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry, respectively. Arsenic mass fractions detected in the mushrooms were covering a range from 0.3 to 22 mg As kg -1 dry mass. For the arsenic speciation, species like arsenobetaine, inorganic arsenic, or dimethylarsinic acid were found, which are commonly detected in mushrooms, but it was also proven that the recently discovered novel compound homoarsenocholine is present in Amanita muscaria and Ramaria sanguinea. Moreover, a previously unidentified arsenic species was isolated from Ramaria sanguinea and identified as trimethylarsonioacetamide, or in short: arsenobetaine amide. This new arsenical was synthesized and verified by spiking experiments to be present in all investigated mushroom samples. Arsenobetaine amide could be an important intermediate to further elucidate the biotransformation pathways of arsenic in the environment., (© 2024. The Author(s).)

Background: Inorganic arsenic (iAs) is a widespread toxic metalloid. It is well-known that iAs metabolism and its toxicity are mediated by polymorphisms in AS3MT and other genes. However, studies during pregnancy are scarce. We aimed to examine the role of genetic polymorphisms in AS3MT, GSTO2, N6AMT1, MTHFR, MTR, FTCD, CBS, and FOLH1 in iAs methylation efficiency during pregnancy., Methods: The study included 541 pregnant participants from the INMA (Environment and Childhood) Spanish cohort. Using high-performance liquid chromatography coupled to inductively coupled plasma-tandem mass, we measured arsenic (iAs and the metabolites monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)) in urine samples collected during the first trimester. iAs methylation efficiency was determined based on relative concentrations of the As metabolites in urine (%MMA, %DMA, and %iAs). Thirty-two single nucleotide polymorphisms (SNPs) in nine genes were determined in maternal DNA; AS3MT haplotypes were inferred. We assessed the association between genotypes/haplotypes and maternal As methylation efficiency using multivariate linear regression models., Results: The median %MMA and %DMA were 5.3 %, and 89 %, respectively. Ancestral alleles of AS3MT SNPs (rs3740393, rs3740390, rs11191453, and rs11191454) were significantly associated with higher %MMA, %iAs, and lower %DMA. Pregnant participants with zero copies of the GGCTTCAC AS3MT haplotype presented a higher %MMA. Statistically significant associations were also found for the FOLH1 SNP rs202676 (β 0.89 95%CI: 0.24, 1.55 for carriers of the G allele vs. the A allele)., Conclusions: Our study shows that ancestral alleles in AS3MT polymorphisms were associated with lower As methylation efficiency in early pregnancy and suggests that FOLH1 also plays a role in As methylation efficiency. These results support the hypothesis that As metabolism is multigenic, being a key element for identifying susceptible populations., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Colloidal InAs quantum dots (QDs) are widely studied as a printable optoelectronic material for short-wave infrared (SWIR) that is not restricted by regulations on hazardous substances. Such applications, however, require synthetic procedures that yield QDs with adjustable sizes at the end of the reaction. Here, we show that such one-size-one-batch protocols can be realized through temperature profiles that involve a rapid transition from a lower injection temperature to a higher reaction temperature. By expediting the transition to the reaction temperature and reducing the overall synthesis concentration, we can tune QD sizes from 4.5 to 10 nm, the latter corresponding to a band gap transition at 1600 nm. We argue that the temperature ramps provide a more distinct separation between nucleation at low temperature and growth at high temperature such that larger QDs are obtained by minimizing the nucleation time. The synthetic procedures introduced here will strongly promote the development of a SWIR optoelectronic technology based on InAs QDs, while the use of temperature profiles to steer a colloidal synthesis can find applications well beyond the specific case of InAs QDs.

We explored the influence of child and maternal single nucleotide polymorphisms (SNPs) in genes related to neurological function and arsenic metabolism (i.e., ABCA1 , ABCB1 , PON1 , CYP3A , BDNF , GSTP1 , MT2A , and APOE as well as AS3MT ) on the association between prenatal arsenic (As) exposure and methylation efficiency and neuropsychological development in 4-5-year-old children. Participants were 549 mother-child pairs from the INMA (Environment and Childhood) Spanish Project. We measured inorganic arsenic (iAs) and the metabolites monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) in urine samples collected during pregnancy. Neuropsychological development was assessed at the age of 4-5 years using the McCarthy Scales of Children's Abilities (MSCA). Several SNPs were determined in maternal and child DNA; AS3MT and APOE haplotypes were inferred. The median ∑As (sum of iAs, DMA, and MMA) was 7.08 μg/g creatinine. Statistically significant interactions for children's APOE haplotype were observed. Specifically, ε4-carrier children had consistently lower MSCA scores in several scales with increasing ∑As and MMA concentrations. These results provide evidence regarding the neurotoxic effects of early life exposure to As, observing that the APOE ε4 allele could make children more vulnerable to this exposure.

Thelephora penicillata is an ectomycorrhizal mushroom that can accumulate extraordinarily high concentrations of Cd, As, Cu, and Zn in its fruit-bodies. To better understand its element accumulation ability, we compared the element concentrations in T. penicillata with 10 distinct ectomycorrhizal mushroom species growing at the same site (Karlina Pila, Czech Republic). On average, T. penicillata accumulated 330, 2130, 26, and 4 times more Cd, As, Cu, and Zn, respectively, than other mushrooms. Size-exclusion chromatography and an electrophoretic analysis of T. penicillata cell extracts indicate that intracellular Cd may be present mainly in >1 kDa, presumably compartmentalized, Cd species, and partially binding with 6-kDa cysteinyl-containing peptide(s) resembling metallothioneins. The cadmium isotopic composition of mushroom fruit-bodies, soil digests, and soil extracts was investigated by thermal ionization mass spectrometry (TIMS) with double spike correction. The isotopic composition (δ 114/110 Cd) of ectomycorrhizal mushrooms from Karlina Pila varied in a wide range of -0.37 to +0.14 ‰. However, remarkably low δ 114/110 Cd values were observed in the majority of the investigated mushrooms when compared to the relatively homogeneous Cd isotopic composition of bulk soil (δ 114/110 Cd = +0.09 ‰) and the comparatively heavy isotopic composition of soil extracts (mean δ 114/110 Cd values of +0.11 ± 0.01 ‰ and +0.22 ± 0.01 ‰, depending on the extraction method). The isotopic composition of Cd hyperaccumulated in T. penicillata essentially matched the mycoavailable soil Cd fraction. However, most isotopic data indicates isotopic fractionation at the soil/fruit-body interface, which could be of environmental significance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

This work describes the development of a novel method for quantitative mapping of Hg and Se in mushroom fruit body tissues with laser ablation coupled to inductively coupled plasma-mass spectrometry (LA-ICP-MS). Different parameters of the protocol for preparation of the standards used for quantification via external calibration were assessed, e.g., the dissolution temperature of gelatin standards and the addition of chitosan and L-cysteine as additives to the gelatin-based calibration droplets to better match the sample matrix. While chitosan was not suited for this purpose, the presence of L-cysteine considerably improved the figures of merit of the calibration, leading to limits of detection of 0.006 and 0.3 µg g -1 for Hg and Se, respectively, at a pixel size of 20 × 20 µm. Further, an in-house reference material, ideally suited for the validation of the method for application to mushroom samples, was successfully prepared from a paste of Boletus edulis. The newly developed method was used to investigate the distribution of Hg and Se in tissue sections of five porcini mushroom individuals of three different species (Boletus edulis, Boletus aereus, and Boletus pinophilus) and one sample of a parasol mushroom (Macrolepiota procera). For one sample, additional areas were ablated at higher spatial resolution, with a laser spot size down to 5 µm, which allows a detailed investigation of the spatial distribution of Hg and Se in mushrooms., (© 2022. The Author(s).)

Fruit-bodies of six Thelephora species (Fungi, Basidiomycota, Thelephoraceae) were analyzed for their trace element concentrations. In Thelephora penicillata, extremely high concentrations of Cd and As were found, followed by highly elevated concentrations of Cu and Zn. The highest accumulation ability was found for Cd with a mean concentration of 1.17 ± 0.37 g kg -1 (dry mass) in fruit-bodies collected from 20 unpolluted sites; the mean As concentration was 0.878 ± 0.242 g kg -1 . Furthermore, striking accumulation of Se (923 ± 28 mg kg -1 ) was found in one sample of T. vialis and elevated concentrations of S were detected in T. palmata (19.6 ± 5.9 g kg -1 ). The analyzed Thelephora species were sequenced and, based on the Maximum Likelihood phylogenetic analysis (ITS rDNA) of the genus, possible other Thelephora (hyper)accumulators were predicted on the basis of their phylogenetic relationship with the discovered (hyper)accumulators. The striking ability of T. penicillata to accumulate simultaneously Cd, As, Cu, and Zn has no parallel in the Fungal Kingdom and raises the question of a biological importance of metal(loid) hyperaccumulation in mushrooms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Arsenic can be toxic to living organisms, depending not only on the concentration, but also its chemical form. The aim of this study was to determine arsenic concentrations and perform arsenic speciation analysis for the first time in honeybees, to evaluate their potential as biomonitors. Highest arsenic concentrations were determined in the vicinity of coal fired thermal power plants (367 µg kg -1 ), followed by an urban region (213 µg kg -1 ), with much lower concentrations in an industrial city (28.8 µg kg -1 ) and rural areas (41 µg kg -1 ). Until now, honey bees have never been used to study different arsenic species in the environment. For this reason, four extraction procedures were tested: water, hot water at 90 °C, 20% methanol, and 1% formic acid. Water at 90 °C was able to extract more than 90% of the total arsenic from honey bee samples. Inorganic arsenic (the sum of arsenite and arsenate) accounted for 95% of arsenic species in bees from three locations, except the industrial city, where it represented only 80% of arsenic species, while 15% was present as DMA., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Trace elements in aquatic environments pose a risk to biological communities; this study investigates the total concentrations of arsenic (As), silver (Ag), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), selenium (Se), lead (Pb), and zinc (Zn) within muscle, carapace, liver, and adipose tissues of diamondback terrapins and common snapping turtles in New Jersey. The effects of tissue type, sex, size, and location upon trace element accumulation were studied. The data obtained indicates that within diamondback terrapins and common snapping turtles, trace element accumulations displayed a significant difference among tissue types and sex (p < 0.005). The data indicates that Ag, Cd, Cu, and Hg can accumulate within the liver of diamondback terrapin. Se was found to accumulate in the livers of both diamondback terrapin and common snapping turtles. The highest mean concentrations of Co, Cr, Ni, and Pb were found in the carapace of both turtle species. Sex was found to have an impact on As, Hg, and Zn accumulation within different tissue types of diamondback terrapins. Diamondback terrapin males were found to have higher concentrations of As within the carapace. Diamondback terrapin females possessed higher concentrations of Hg in muscle tissues and Hg and Zn in the carapace. Turtle size and collection location land type and land cover did not display any correlation with trace element bioaccumulation for either species., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

We report the first halogen speciation analysis study by high performance liquid chromatography coupled with inductively coupled plasma tandem mass spectrometry (HPLC-ICPMS/MS) in the fruiting bodies of various mushroom species. Non-targeted speciation analysis revealed the occurrence of dichloroacetic acid (DCAA) in the edible mushroom Russula nigricans. Multiple samples of this mushroom (n = 5) collected from different geographic non-industrial regions in two different countries confirmed the consistent presence of this species at a relatively narrow concentration range (23-37 mg kg -1 ), whereas no other chlorinated acetic acid (e.g. chloroacetic acid and trichloroacetic acid) was detected. Neither DCAA nor any other chlorinated acetic acid were detected in any of the other mushroom species investigated in the present study, including seven different mushroom species of the same genus Russula, even though all mushrooms were collected from the same non-industrial geographic regions. Together with the previously reported biological activities of DCAA, these findings collectively suggest biosynthesis of this compound as an explanation for its dominant presence in R. nigricans, and constitute the first example of the dominant natural occurrence of this compound over other chlorinated acetic acids in a living organism. This may warrant a change in our view of the occurrence of dichloroacetic acid in nature, where primarily considered as a pollutant arising from water disinfection., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

With the introduction of tandem mass spectrometry to inductively coupled plasma mass spectrometry (ICPMS/MS), the potential for non-targeted elemental metabolomic analysis has been expanded to many non-metals of pivotal biological importance. Arsenic and selenium are trace elements that share chemical similarity with the non-metals phosphorus and sulfur, respectively, and this similarity can be exploited to gain more insight into the incompletely understood biological significance of these metalloids and the evolution of their biochemical pathways. As a proof of concept, we show the applicability of HPLC-ICPMS/MS for non-targeted and parallel speciation analysis of arsenic, selenium, phosphorus, and sulfur in mushrooms-metabolically diverse organisms. Incredibly contrasting levels of diversity were found in the metabolomic profiles of the four investigated elements among the various species along with sharp discrepancies among related elements (e.g. phosphorous vs. arsenic) in certain mushroom species. The present work shows that ICPMS/MS offers a new dimension in non-targeted metabolomic analysis and enables a unique comparative approach in investigating and tracking the biochemistry of related elements in moderately complex organisms., (© The Author(s) 2021. Published by Oxford University Press.)

Broad substrate tolerance and excellent regioselectivity, as well as independence from sensitive cofactors have established benzoic acid decarboxylases from microbial sources as efficient biocatalysts. Robustness under process conditions makes them particularly attractive for preparative-scale applications. The divalent metal-dependent enzymes are capable of catalyzing the reversible non-oxidative (de)carboxylation of a variety of electron-rich (hetero)aromatic substrates analogously to the chemical Kolbe-Schmitt reaction. Elemental mass spectrometry supported by crystal structure elucidation and quantum chemical calculations verified the presence of a catalytically relevant Mg 2+ complexed in the active site of 2,3-dihydroxybenoic acid decarboxylase from Aspergillus oryzae (2,3-DHBD&#95;Ao). This unique example with respect to the nature of the metal is in contrast to mechanistically related decarboxylases, which generally have Zn 2+ or Mn 2+ as the catalytically active metal., (© 2020 The Authors. ChemBioChem published by Wiley-VCH GmbH.)

The As concentrations, along with 34 other elements, and the As speciation were investigated in wild-grown samples of the parasitic mushroom Tolypocladium ophioglossoides with inductively coupled plasma mass spectrometry (ICPMS) and high performance liquid chromatography coupled to ICPMS. The As concentrations were 0.070-3.44 mg kg -1 dry mass. More remarkable was the As speciation, where up to 56% of the extracted As were found to be an unknown As species, which was marginally retained under anion- and also cation-exchange conditions. After testing several different chromatographic settings, the compound was finally isolated and identified as 2-(sulfoxyethyl) trimethylarsonium ion (in short: arsenocholine-O-sulfate) with high resolution mass spectrometry. The compound was synthesized and further quantified in all investigated samples via ion-pair chromatography coupled to ICPMS. In addition to the high abundance of arsenocholine-O-sulfate in T. ophioglossoides, small amounts of this As species were also detected in one sample of the host mushroom, Elaphomyces asperulus. In a sample of another parasitic mushroom, Ophiocordyceps sinensis, arsenocholine-O-sulfate could not be detected, but the main species was another unknown compound that was oxidized to inorganic As(V) with hydrogen peroxide. This is the first discovery of arsenocholine-O-sulfate in nature. It is possible that it is present in many other organisms, at least in low concentrations, and just has not been detected there yet because of its unusual chromatographic behavior. The existence of arsenocholine-O-sulfate brings up questions again about the biotransformation pathways of As in the environment and the specific behavior of fungi., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The Violet Crown Cup, Sarcosphaera coronaria, is a rather inconspicuous mushroom, but with an interesting and unresolved mystery. In earlier days, the mushroom was considered edible, but several poisonings were reported in the early 20 th century. The reason for the seemingly sporadic toxicity of S. coronaria is still unknown. One possible explanation is arsenic, since Crown Cups can take up high amounts of this element. We investigated the arsenic concentration and arsenic speciation in S. coronaria with inductively coupled plasma mass spectrometry (ICPMS) and HPLC coupled to ICPMS and found up to incredible 0.9% As (dry mass). Most of it was present as methylarsonic acid (MA), a less toxic form of this element. However, low concentrations of the highly toxic methylarsonous acid [MA (III)] were also detected. The amounts were too low to pose an acute risk for consumers, but the concentration of MA (III) significantly increased during simulated gastric digestion. We could not unambiguously identify arsenic as the toxic constituent of S. coronaria, but we demonstrated that the extremely toxic MA (III) can be formed under certain circumstances, which should be carefully investigated in future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Since the discovery of the "fish arsenic" arsenobetaine in a mushroom, arsenic species have been studied in all kinds of mushrooms, with very diverse results, for more than 20 years. Depending on the fungal species, inorganic arsenic, methylarsonic acid, dimethylarsinic acid, arsenobetaine and a couple of other arsenic-containing compounds have been detected in all kinds of concentrations in natural samples. A rule to predict the arsenic speciation of a new mushroom is yet to be found. Some research has been devoted to the question about the origin of the different arsenic species in mushrooms. It is still not clear whether mushrooms are able to transform arsenic by themselves or if they just take it up from the environment. For the determination of the arsenic species in mushrooms, high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry is used most of the times, but a few alternative approaches exist. This review will give an overview of these different techniques and critically discuss them. The arsenic species that have been found in mushrooms so far will be summarized, and the work that has been devoted to unraveling the origins of these compounds will be discussed in depth. The interesting phenomenon of arsenic hyperaccumulation by mushrooms will be reviewed as well., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Polcalcins are important respiratory panallergens, whose IgE-binding capacity depends on the presence of calcium. Since specific immunotherapy is not yet available for the treatment of polcalcin-sensitized patients, we aimed to develop a molecule for efficient and safe immunotherapy. We generated a hypoallergenic variant of the grass pollen polcalcin Phl p 7 by introducing specific point mutations into the allergen's calcium-binding regions. We thereby followed a mutation strategy that had previously resulted in a hypoallergenic mutant of a calcium-binding food allergen, the major fish allergen parvalbumin. Dot blot assays performed with sera from Phl p 7-sensitized patients showed a drastically reduced IgE reactivity of the Phl p 7 mutant in comparison to wildtype Phl p 7, and basophil activation assays indicated a significantly reduced allergenic activity. Rabbit IgG directed against mutant rPhl p 7 blocked patients' IgE binding to wildtype Phl p 7, indicating the mutant's potential applicability for immunotherapy. Mass spectrometry and circular dichroism experiments showed that the mutant had lost the calcium-binding capacity, but still represented a folded protein. In silico analyses revealed that the hypoallergenicity might be due to fewer negative charges on the molecule's surface and an increased molecular flexibility. We thus generated a hypoallergenic Phl p 7 variant that could be used for immunotherapy of polcalcin-sensitized individuals.

Selenium (Se) and sulfur (S) speciation analysis in edible and medicinal Se enriched P. pulmonarius extracts was performed. Mycelium, colonized substrate, and fruiting bodies at different harvesting times were analyzed using ion-pairing reversed-phase chromatography coupled to an ICPMS/MS detector. Extraction efficiencies in enzymatically digested and aqueous extracts were between 45.3 and 109% for Se, depending on the sample type. Selenomethionine (Se-Met) was found to be the major Se-compound, together with a number of unknown Se-species. Cystine (Cys 2 ), methionine (Met), and sulfate were also detected and quantified in all samples. Most of the Se-Met (84.0%) and Met (75.8%) were found to be in free form in the fruiting body, in contrast with the mycelium where 53.4% of Se-Met and 80.5% of Met is incorporated into proteins., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Collections of Cystoderma carcharias sporocarps were sampled from clean and smelter-polluted sites and analyzed for Ag, As, Cd, Cu, Pb, Se, and Zn contents. Concentrations of all elements were significantly higher in samples from the smelter-polluted area. Except for As and Pb, all elements were effectively accumulated in the sporocarps at both clean and polluted sites. With the highest concentration of 604 mg Cd kg -1 , C. carcharias can be considered as Cd hyperaccumulator. As revealed by HPLC-ICPQQQMS analysis, the As species in sporocarps from clean and polluted areas involved besides the major arsenobetaine a variety of known and unknown arsenicals; the occurrence of dimethylarsinoylacetate and trimethylarsoniopropionate is reported for the first time for gilled fungi (Agaricales). Size-exclusion chromatography of C. carcharias extracts supported by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and RP-HPLC data indicated that detoxification of intracellular Cd and Cu may largely rely on metallothioneins (MT) or MT-like peptides, not phytochelatins., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The C-C bond cleavage catalyzed by metal-dependent iso -orotate decarboxylase (IDCase) from the thymidine salvage pathway is of interest for the elucidation of a (hypothetical) DNA demethylation pathway. IDCase appears also as a promising candidate for the synthetic regioselective carboxylation of N -heteroaromatics. Herein, we report a joint experimental-theoretical study to gain insights into the metal identity, reaction mechanism, and substrate specificity of IDCase. In contrast to previous assumptions, the enzyme is demonstrated by ICPMS/MS measurements to contain a catalytically relevant Mn 2+ rather than Zn 2+ . Quantum chemical calculations revealed that decarboxylation of the natural substrate (5-carboxyuracil) proceeds via a (reverse) electrophilic aromatic substitution with formation of CO 2 . The occurrence of previously proposed tetrahedral carboxylate intermediates with concomitant formation of HCO 3 - could be ruled out on the basis of prohibitively high energy barriers. In contrast to related o -benzoic acid decarboxylases, such as γ-resorcylate decarboxylase and 5-carboxyvanillate decarboxylase, which exhibit a relaxed substrate tolerance for phenolic acids, IDCase shows high substrate fidelity. Structural and energy comparisons suggest that this is caused by a unique hydrogen bonding of the heterocyclic natural substrate (5-carboxyuracil) to the surrounding residues. Analysis of calculated energies also shows that the reverse carboxylation of uracil is impeded by a strongly disfavored uphill reaction.

The arsenic speciation was determined in macrofungi of the Ramaria genus with HPLC coupled to inductively coupled plasma mass spectrometry. Besides arsenic species that are already known for macrofungi, like arsenobetaine or arsenocholine, two compounds that were only known from marine samples so far (trimethylarsoniopropanate and dimethylarsinoylacetate) were found for the first time in a terrestrial sample. An unknown arsenical was isolated and identified as homoarsenocholine. This could be a key intermediate for further elucidation of the biotransformation mechanisms of arsenic., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

The edible ink stain bolete (Cyanoboletus pulverulentus) was found to hyperaccumulate arsenic. We analyzed 39 individual collections determined as C. pulverulentus, mostly from the Czech Republic. According to our results, concentrations of arsenic in C. pulverulentus fruit-bodies may reach 1300mgkg -1 dry weight. In most collections, data for total and bioavailable arsenic in underlying soils were collected but no significant correlation between the soil arsenic content and arsenic concentrations in the associated fruit-bodies was found. Within the fruit-bodies, we found the majority of arsenic accumulated in the hymenium. Besides occasional traces of methylarsonic acid (MA), the arsenic speciation in all mushroom samples consisted solely of dimethylarsinic acid (DMA) and no inorganic arsenic was detected. Because of the carcinogenic potential of DMA, C. pulverulentus should not be recommended as an edible mushroom and its consumption should be restricted., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Arsenic and its species were investigated for the first time in nine collections of Elaphomyces spp. ("deer truffles") from the Czech Republic with inductively coupled plasma mass spectrometry (ICPMS) and high-performance liquid chromatography coupled to ICPMS. The total arsenic concentrations ranged from 12 to 42 mg kg -1 dry mass in samples of E. asperulus and from 120 to 660 mg kg -1 dry mass in E. granulatus and E. muricatus. These concentrations are remarkably high for terrestrial organisms and demonstrate the arsenic-accumulating ability of these fungi. The dominating arsenic species in all samples was methylarsonic acid which accounted for more than 30% of the extractable arsenic. Arsenobetaine, dimethylarsinic acid, and inorganic arsenic were present as well, but only at trace concentrations. Surprisingly, we found high amounts of trimethylarsine oxide in all samples (0.32-28% of the extractable arsenic). Even more remarkable was that all but two samples contained significant amounts of the highly toxic trivalent arsenic compound methylarsonous acid (0.08-0.73% of the extractable arsenic). This is the first report of the occurrence of trimethylarsine oxide and methylarsonous acid at significant concentrations in a terrestrial organism. Our findings point out that there is still a lot to be understood about the biotransformation pathways of arsenic in the terrestrial environment. Graphical abstract Trimethylarsine oxide and methylarsonous acid in "deer truffles".

The total arsenic concentration and the arsenic speciation in urine and feces samples of the two Giant Pandas living at Vienna zoo and of their feed, bamboo, were determined with ICPMS and HPLC-ICPMS. Urine was the main excretion route and accounted for around 90% of the ingested arsenic. The urinary arsenic concentrations were very high, namely up to 179 μg/L. Dimethylarsinic acid (DMA) was the dominating arsenic compound in the urine samples and ranged from 73 to 92% of the total arsenic, which is unusually high for a terrestrial mammal. The feces samples contained around 70% inorganic arsenic and 30% DMA. The arsenic concentrations in the bamboo samples were between 16 and 920 μg/kg dry mass. The main arsenic species in the bamboo extracts was inorganic arsenic. This indicates that the Giant Panda possesses a unique way of very efficiently methylating and excreting the provided inorganic arsenic. This could be essential for the survival of the animal in its natural habitat, because parts of this area are contaminated with arsenic., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Cortinarius coalescens Kärcher & Seibt is a rare European species of the subgenus Phlegmacium , section Phlegmacioides , neglected in recent molecular studies. New primers (CortF and CortR) designed for species in the section Phlegmacioides allowed to obtain ITS rDNA sequence data from the holotype collection of C. coalescens ; according to the results, this epithet has priority over C. crassorum Rob. Henry ex Rob. Henry, C. pardinus Reumaux, and C. parargutus Bidaud, Moënne-Locc. & Reumaux. Morphological and ecological observations on recent collections of C. coalescens from the Czech Republic in comparison with the co-occurring C. largus are discussed. Nomenclatural and taxonomic comments on C. tomentosus Rob. Henry, C. balteatotomentosus Rob. Henry, and C. subtomentosus Reumaux are also provided. So far, C. coalescens is known with certainty from Germany, France, and the Czech Republic, where it grows in deciduous forests on acid to neutral soils. Arsenic and its compounds were determined in C. coalescens and related species of the section Phlegmacioides : C. largus , C. pseudodaulnoyae , and C. variecolor . Total arsenic concentrations were in the range 3.6-30.2 mg kg -1 (dry matter) and arsenobetaine was the major arsenic compound.

Biodegradable magnesium implants are under investigation because of their promising properties as medical devices. For enhancing the mechanical properties and the degradation resistance, rare earth elements are often used as alloying elements. In this study Mg10Gd pins were implanted into Sprague-Dawley® rats. The pin volume loss and a possible accumulation of magnesium and gadolinium in the rats' organs and blood were investigated in a long-term study over 36weeks. The results showed that Mg10Gd is a fast disintegrating material. Already 12weeks after implantation the alloy is fragmented to smaller particles, which can be found within the intramedullary cavity and the cortical bones. They disturbed the bone remodeling until the end of the study. The results concerning the elements' distribution in the animals' bodies were even more striking, since an accumulation of gadolinium could be observed in the investigated organs over the whole time span. The most affected tissue was the spleen, with up to 3240μgGd/kg wet mass, followed by the lung, liver and kidney (up to 1040, 685 and 207μgGd/kg). In the brain, muscle and heart, the gadolinium concentrations were much smaller (less than 20μg/kg), but an accumulation could still be detected. Interestingly, blood serum samples showed no accumulation of magnesium and gadolinium. This is the first time that an accumulation of gadolinium in animal organs was observed after the application of a gadolinium-containing degradable magnesium implant. These findings demonstrate the importance of future investigations concerning the distribution of the constituents of new biodegradable materials in the body, to ensure the patients' safety., Statement of Significance: In the last years, biodegradable Mg alloys are under investigation due to their promising properties as orthopaedic devices used for bone fracture stabilization. Gadolinium as Rare Earth Element enhances the mechanical properties of Mg-Gd alloys but its toxicity in humans is still questionable. Up to now, there is no study investigating the elements' metabolism of a REE-containing Magnesium alloy in an animal model. In this study, we examined the gadolinium distribution and accumulation in rat organs during the degradation of Mg10Gd. Our findings showed that Gd is accumulating in the animal organs, especially in spleen, liver and kidney. This study is of crucial benefit regarding a safe application of REE-containing Magnesium alloys in humans., (Copyright © 2016. Published by Elsevier Ltd.)

Excessive arsenic content in drinking water poses health risks to millions of people worldwide. Inorganic arsenic (iAs) in groundwater exceeding the 10μg/l maximum contaminant level (MCL) set by the World Health Organization (WHO) is characteristic for intermediate-depth aquifers over large areas of the Pannonian Basin in Central Europe. In western Romania, near the border with Hungary, Arad, Bihor, and Timis counties use drinking water coming partially or entirely from iAs contaminated aquifers. In nearby Arad and Bihor counties, more than 45,000 people are exposed to iAs over 10μg/l via public drinking water sources. However, comparable data are unavailable for Timis County. To begin to address this data gap, we determined iAs in 124 public and private Timis County drinking water sources, including wells and taps, used by pregnant women participating in a case-control study of spontaneous loss. Levels in water sources were low overall (median=3.0; range=<0.5-175μg/l), although higher in wells (median=3.1, range=<0.5-1.75) than in community taps (median=2.7, range=<0.5-36.4). In a subsample of 20 control women we measured urine biomarkers of iAs exposure, including iAs (arsenite and arsenate), dimethylarsinic acid (DMA), and methylarsonic acid (MMA). Median values were higher among 10 women using iAs contaminated drinking water sources compared to 10 women using uncontaminated sources for urine total iAs (6.6 vs. 5.0μg/l, P=0.24) and DMA (5.5 vs. 4.2μg/l, P=0.31). The results suggested that the origin of urine total iAs (r=0.35, P=0.13) and DMA (r=0.31, P=0.18) must have been not only iAs in drinking-water but also some other source. Exposure of pregnant women to arsenic via drinking water in Timis County appears to be lower than for surrounding counties; however, it deserves a more definitive investigation as to its origin and the regional distribution of its risk potential., (Copyright © 2015 Elsevier GmbH. All rights reserved.)