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The complete characterization of selenium-enriched yeast in terms of selenium species has been the goal of extensive research for the last three decades. This contribution addresses the two outstanding questions: the mass balance of the identified and reported selenium species and the possible presence of inorganic selenium. For this purpose, four procedures have been designed combining, in diverse order, the principal steps of selenium speciation analysis in Se-rich yeast: extraction of the Se-metabolome, derivatization of cysteine and Se-cysteine (SeCys) residues, proteolysis, and definitive Se recovery using SDS extraction, followed by mineralization. The recovery of selenium in each step and its speciation were controlled by ICP MS and by reversed-phase HPLC-ICP MS, respectively. The study, carried out for the SELM-1 reference material, demonstrated the presence of about 10% of inorganic selenium and a serious risk of losses of SeCys during derivatization and proteolysis. As result of our work, we postulate the following values for SELM-1: Se-metabolome fraction (SeMF) 14.8 ± 0.7%; total selenomethionine (SeMet) 66.2 ± 2.7% (including ca. 1.5% SeMet present in the SeMF); total SeCys 12.5 ± 1.5% (including 2% of SeCys present in the Se-MF); total inorganic selenium 9.7 ± 1.7%, accounting for > 99.8% of the selenium. [ABSTRACT FROM AUTHOR]

The chloroplast (cp.) genome, also known as plastome, plays crucial roles in plant survival, adaptation, and evolution. The stable genetic structure of cp. genomes provides an ideal system for investigating species evolution. We sequenced three complete cp. genome sequences of Capsicum species and analyzed them using sequences of various Capsicum species retrieved from the NCBI database. The cp. genome of Capsicum species maintains a well-preserved quadripartite structure consisting of two inverted repeats (IRs) flanked by a large single copy (LSC) region and a small single copy (SSC) region. The sizes of cp. genome sequences ranged from 156,583 bp (C. lycianthoides) to 157,390 bp (C.pubescens). A total of 127–132 unique genes, including 83–87 protein-coding, 36–37 tRNA, and eight rRNA genes, were predicted. Comparison of cp. genomes of 10 Capsicum species revealed high sequence similarity in genome-wide organization and gene arrangements. Fragments of trnT-UGU/trnL-UAA, ccsA, ndhD, rps12, and ycf1 were identified as variable regions, and nucleotide variability of LSC and SSC was higher than that of IR. Phylogenetic speciation analysis showed that the major domesticated C. annuum species were the most extensively divergent species and closely related to C. tovarii and C. frutescens. Analysis of divergent times suggested that a substantial range of speciation events started occurring ~ 25.79 million years ago (Mya). Overall, comparative analysis of cp. genomes of Capsicum species not only offers new insights into their genetic variation and phylogenetic relationships, but also lays a foundation for evolutionary history, genetic diversity, conservation, and biological breeding of Capsicum species. [ABSTRACT FROM AUTHOR]

This study addresses the development and validation of an analytical method for speciation analysis of mercury (inorganic/Hg2+ and methylmercury/CH3Hg+) in fishery products. The Hg species are separated by reversed-phase (RP) high-performance liquid chromatography (HPLC) coupled to inductively coupled plasma mass spectrometry (ICP-MS). The effective separation of Hg2+ and CH3Hg+ was achieved in <8 min using a peptide mapping RP column and a mobile phase containing 2-mercaptoethanol at 0.25% (v/v) and methanol at 1% (v/v). The optimization was carried out using an experimental design through response surface methodology (RSM) with central composite design (CCD), addressing both the HPLC separation and the sample extraction. The method validation was carried out based on the accuracy profile approach. For this purpose, six series of measurements were carried out in duplicate over a time span of 2 months. The limits of quantification (LOQ) were 2.5 µg/kg (wet weight, ww) for CH3Hg+ and 1.2 µg/kg (ww) for Hg2+. The intermediate reproducibility in terms of coefficient of variation (CVR) was <6%. The bias (%) obtained for the analysis of four certified reference materials (CRMs), namely TORT-3 (lobster hepatopancreas), SRM 1566-b (oyster tissue), SQID-1 (cuttlefish) and NMIJ CRM 7402-a (cod fish tissue) was <7%. This demonstrates the method robustness and suitability for routine speciation analysis of CH3Hg+ and Hg2+ in fishery products. The method is intended to be applied for the analysis of the panel of fishery products and fish-based foods in the framework of the (ongoing) third French Total Diet Study. [ABSTRACT FROM AUTHOR]

The issue of soil contamination by heavy metals is widely acknowledged. Some plants, including medicinal species like St. John's wort (Hypericum perforatum L.), exhibit accumulation traits, allowing them to accumulate elevated levels of metals, e.g., cadmium (Cd), within their cells. Selenium (Se) may increase the tolerance of plants to abiotic stress caused by the presence of heavy metal in the environment. Depending on its form (oxidation state, organic/inorganic), Se influences plant growth, secondary metabolite content, and biotic stress, as well as incorporates into shoots, providing economic and health benefits for consumers. So far, there are no data on the influence of organic Se(IV) on plants. Our study aimed to determine the effect of organic Se(IV) on the growth, active compound levels (anthranoids, polyphenols), and ultrastructure of St. John's wort without and under cadmium stress. The phytochemical analysis and microscopic examination was performed on shoots from different days of St. John's wort in vitro culture on a few variants of Murashige and Skoog medium with Cd (25 and 400 µM) and/or organic Se (IV). Exposure to Se(IV) did not affect hypericins but increased the polyphenol content in the shoots and the biomass. Se(IV) caused an increase in starch grain number in chloroplasts, whereas Cd exposure resulted in the degradation of the chloroplast structure, increased cell vacuolation, as well as swollen mitochondrial cristae. The addition of Se(IV) to these combinations reduced the degree of degradation and growth inhibition and a high content of Se(IV) in plants was observed. Se(IV) had no impact on Cd content at environmental Cd concentrations, but showed an effect at extremely high Cd concentrations. Thus, organic Se(IV) has a beneficial effect on St. John's wort growth, polyphenol content, and incorporation in shoots and prevents Cd toxicity. Media enriched with organic Se(IV) have both economic advantages and health benefits due to a higher plant growth rate and increased concentrations of polyphenols with strong antioxidant properties, relatively enriched with Se. However, organic Se(IV) should be used with caution in polluted areas. In perspective, speciation analysis and molecular study are crucial to understand the fate and effect of Se (IV) on plants. [ABSTRACT FROM AUTHOR]

Antimony (Sb) contamination poses significant environmental and health concerns due to its toxic nature and widespread presence, largely from anthropogenic activities. This study addresses the urgent need for an accurate speciation analysis of Sb, particularly in water sources, emphasizing its migration from polyethylene terephthalate (PET) plastic materials. Current methodologies primarily focus on total Sb content, leaving a critical knowledge gap for its speciation. Here, we present a novel analytical approach utilizing frontal chromatography coupled with inductively coupled plasma mass spectrometry (FC-ICP-MS) for the rapid speciation analysis of Sb(III) and Sb(V) in water. Systematic optimization of the FC-ICP-MS method was achieved through multivariate data analysis, resulting in a remarkably short analysis time of 150 s with a limit of detection below 1 ng kg−1. The optimized method was then applied to characterize PET leaching, revealing a marked effect of the plastic aging and manufacturing process not only on the total amount of Sb released but also on the nature of leached Sb species. This evidence demonstrates the effectiveness of the FC-ICP-MS approach in addressing such an environmental concern, benchmarking a new standard for Sb speciation analysis in consideration of its simplicity, cost effectiveness, greenness, and broad applicability in environmental and health monitoring. [ABSTRACT FROM AUTHOR]

The aim of this work is to develop a simple, sensitive, and reliable colorimetric test method for the visual detection of Fe(II) and Fe(III) in water. The sample solution of Fe(III) was initially complexed with chromeazurol S (CAS) followed by ion-pair association with cetyltrimethylammonium bromide (CTAB) in the presence of perchlorate ions. This led to the formation of a bulky and insoluble fluffy precipitate involving the physical entrapment of the ternary complex of Fe-CAS-CTAB, which floats on the top of the solution. Depending on the concentration of Fe(III), this type of ternary complex produces an impressive color change from reddish magenta to purple and then to cyan-blue, easily detectable with the naked eye without the need for expensive instrumentation. The ternary-colored complex was formed instantly and remained stable for at least 8 h with constant absorbance. For the determination of total iron and Fe(II), complete oxidation of Fe(II) to Fe(III) was carried out using 100 μL of KMnO4 (0.005%). The minimal response with the test method was found to be about 5 ng/mL of Fe(III) in 2 min of the total sample testing procedure. However, Fe(III) could be quantified using a spectrophotometer after dissolving the fluffy precipitate in toluene solvent. The calibration graph was linear in the range of 5–30 ng/mL of Fe(III) with a correlation coefficient of 0.9931 and a limit of detection of 0.9 ng/mL. The relative standard deviation was found to be less than 6%. At the end of the study, the efficacy of the method was evaluated by its application to groundwater and thermal power plant coolant waters. [ABSTRACT FROM AUTHOR]

Selenium (Se) is an essential trace element for humans and animals, and an excess of or deficiency in Se is harmful to health. Research on the selenium enrichment zone began in the late 1970s in Shuang'an, Ziyang, southern Shaanxi Province. Naore village is only one selenosis area in Shuang'an, Ziyang, China. Different scholars have conducted systematic studies on the occurrence of selenium, its organic geochemistry and biomarkers, and its content and enrichment patterns in this area. This study applied the TIMA (TESCAN integrated mineral analyzer) for the first time to conduct detailed mineralogical work. The minerals included quartz, carbonate minerals (calcite and dolomite), feldspar (plagioclase, albite, and orthoclase), biotite and muscovite, clay minerals (chlorite and kaolinite), hematite, pyrite, and accessory minerals (almandine, olivine, zircon, and apatite) in Naore village, Ziyang, Shaanxi Province. The ATi index (100 × apatite/(apatite + tourmaline)) is used to determine the source of heavy minerals and the degree of heavy minerals' weathering. The content POS (100 × (pyroxene + olivine + spinel)/transparent heavy mineral) of olivine, pyroxene, and spinel in heavy minerals can reflect the contribution of basic and ultrabasic rocks in the source area. The ATi and POS indexes for the heavy minerals in the research area were 91.83~99.96 and 0.01~18.75, respectively, reflecting the abundance of volcanic rock material in their source. In addition, the migration, transformation, bioavailability, and toxicity of selenium in the environment are closely related to its species. The species of selenium in various selenium-rich areas (Naore, Wamiao, and Guanquan) mainly include unusable residues and organic forms, followed by humic-acid-bound selenium. The proportions of water-soluble, exchangeable, and carbonate-bound selenium are relatively small, and the proportion of Fe-Mn oxide-bound selenium is the lowest. [ABSTRACT FROM AUTHOR]

The mercury cell manufacturing process, which has been extensively used in chlor-alkali plants to produce chlorine and caustic soda by electrolysis, represents a major source of Hg environmental pollution. At Saline di Volterra (Tuscany, Italy), solution mining by pumping water into halite deposits was applied to produce brines for a mercury-cell chlor-alkali plant. The Hg-contaminated, exhausted brines were pumped back at depth into the rock salt field in order to renew the available resources. Activities ceased in 1994, following the leakage dispersion of highly contaminated Hg(0)-bearing brines into the environment. The mercury content in the soil, measured during a survey conducted in 2000, reached 334 mg/kg, highlighting diffuse contamination in the floodplain. By 2009, the Hg concentration had generally decreased and was mostly confined to the topsoil layer. In order to evaluate the present Hg soil pollution, a geochemical survey was carried out in 2023, almost thirty years after the contamination event. The obtained data indicated the occurrence of legacy Hg, which reached 25.5 mg/kg in some soil samples. Speciation analysis for the most contaminated soil revealed that Hg(0) represented about 17.3% of the total Hg and that water-soluble and organic Hg fractions were negligible. These results suggest that the originally released metallic mercury has volatilized and likely oxidized, becoming practically immobile in the soil. A risk assessment, performed by applying Hg speciation analysis, indicated that the mercury in the soil does not carry a risk of non-cancerous effects for different exposure routes in case of subsequent use of the site and that the formerly contaminated area can now be converted into a leisure area. [ABSTRACT FROM AUTHOR]

In the last decades, the determination of trace elements in biological materials has emerged as an important area of study because of its relevance to human health and the environment. Inductively coupled plasma mass spectrometry (ICP-MS) has proven to be a powerful tool for trace element analysis, owing to its high sensitivity and ability to determine several elements in a single measurement. However, given the complex nature of biological matrices and the presence of elements, most of them at ultratrace levels, it becomes crucial to complement ICP-MS with preconcentration techniques to increase the sensitivity and selectivity of analytical methods. This article presents an exhaustive overview of liquid- and solid-phase preconcentration techniques used in combination with ICP-MS for trace element determination in different biological samples from 2000 to the present. An in-depth discussion of the advances on the application of state-of-the-art solvents and materials in trace element extraction and preconcentration is presented. Special attention is given to different strategies for elemental speciation analysis, employing both chromatographic and non-chromatographic techniques. The role of automation in these methodologies is also described. Finally, future trends and challenges related to this topic are discussed. [ABSTRACT FROM AUTHOR]

Speciation analysis plays a key role in understanding the biological activity and toxicity of an element. So far, classical speciation analysis focused only on the dissolved fraction of an elemental species, whereas nanoparticle forms of analytes are being widely found in consumer and industrial products. A significant contributor to human exposure to nanoparticles is through food into which nanoparticles can be incorporated from endogenous sources or they may be formed naturally in the living organisms. Nanoparticles often undergo changes in the food matrices and upon consumption, in the gastrointestinal tract, which present a significant challenge to their characterisation. Therefore, a combination of both classical and nanoparticle speciation analytical techniques is needed for the characterisation of both dissolved and particulate forms of the chemical species. This article presents and discusses the current trends in analysis of nanoparticle behaviour in the gastrointestinal tract and formation and characterisation of biogenic nanoparticles. [ABSTRACT FROM AUTHOR]

Hexavalent chromium (Cr(VI)) is known as the most hazardous species of chromium. Speciation analysis of Cr in foods is of a great significance for assessing its influences on human health. In this study, a fast HPLC-ICP-MS method for the determination of Cr(VI) was developed for determining the content of Cr(VI) and also investigating its transformation in foods. The developed method employs an alkali extraction and weak anion-exchange column separation for distinguishing the Cr species, facilitating accurate Cr(VI) quantification within 1.5 min. This technique was applied to determine the Cr(VI) levels in a range of food products, including yoghurt, milk powder, rice flour, orange juice, green tea, white vinegar, and whole wheat bread. The results showed that no Cr(VI) was detected in these food products. Spiking experiments revealed that the recovery rate of Cr(VI) decreased with the increase in its contact time with food products. A further exploration of Cr(VI) in various food components such as vitamin C, tea polyphenols, whey proteins, gelatin, fructose, and cellulose indicated the conversion of Cr(VI) to organic Cr(III) over a period from 20 min to 60 h. It was found that high temperatures and acidic conditions accelerated the rate of Cr(VI) conversion to organic Cr(III) in the six food components mentioned above. This evidence suggests that natural reducing substances in foods probably prevent the occurrence of Cr(VI). [ABSTRACT FROM AUTHOR]

The production of selenium-enriched fish can contribute to alleviating selenium deficiency in human diets. However, it is still unclear which selenium source, as an additive, can efficiently and cost-effectively produce high-quality selenium-enriched fish. This study evaluated the effects of selenium nanoparticles (SeNP), selenite, and selenomethionine (SeMet) on the growth, antioxidant capacity, selenium content, selenium speciation, and meat quality of grass carp. Ten diets were prepared, including a basal diet (BD) and three concentrations (0.1, 0.3, and 0.9 mg/kg) of SeNP, selenite, and SeMet. A total of 600 fish (250.79 ± 1.57 g) were randomly assigned to 30 tanks (3 tanks/group). Fish were fed the experimental diet three times daily for 60 d. In this study, SeNP most significantly promoted the growth and antioxidant capacity of grass carp, with 0.3 mg/kg SeNP identified as the optimal additive concentration. Additionally, SeNP demonstrated equally excellent bioavailability as SeMet and significantly increased the content of SeMet in grass carp (Ctenopharyngodon idella) muscle. Furthermore, compared to SeMet and selenite, dietary SeNP could more significantly enhance the content of selenocysteine (SeCys2) and methylselenocysteine (MeSeCys) in grass carp muscle tissue. In addition, we have demonstrated that SeCys2 and MeSeCys promote apoptosis of cancer cells (HeLa) through the mitochondrial apoptotic pathway (involving Bax and Bcl-2). Furthermore, as an additive, 0.3 mg/kg SeNP significantly improved the flesh quality of grass carp by reducing crude fat and heavy metal content, as well as increasing the levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the ratio of n-3/n-6 polyunsaturated fatty acid (PUFA). In summary, SeNP is the most suitable additive for producing selenium-enriched fish.

The treatment of laboratory waste containing arsenic compounds should be part of the chemical analysis protocol in educational and research institutions. An alternative procedure for the treatment of these residues is proposed for the development of a didactic analytical route in the detection of As3+, As5+, MMA (monomethylarsonic acid) and DMA (dimethylarsinic acid). The treatment is based on the coprecipitation of inorganic arsenic species with a quaternary ammonium salt (tetra-n-butylammonium perchlorate) in suspension. Detection occurred by controlling the hydride generation reactions and Atomic Absorption Spectrometry. The methylated species MMA and DMA remain in the supernatant and can be monitored by adjusting the pH, concentration of the borohydride reducer, and the use of auxiliary reducers (hydroxylamine hydrochloride and KI). Satisfactory selective detectability was obtained for each arsenic species present in the waste sample. This work contributes to the development of experiments to be implemented in Qualitative Analytical Chemistry and Instrumental Analysis classes. The results allow to approach the chemical vapor generation, which is generally not well explored in undergraduate classes. Discussion of this procedure is supported by a teaching proposal based on the theory of nascent hydrogen for inorganic arsenic species and the nucleophilic performance of the hydride ion for methylated species. This approach allows the student to contextualize important concepts such as Lewis structure, oxidation state and kinetics of arsenic hydride generation reactions. This interdisciplinary contextualization forms a common theoretical basis, preparing and enabling the student to research speciation analysis by hydride generation and to understand the most accepted theories. [ABSTRACT FROM AUTHOR]

This research evaluates the modification of the lithium carbonate (Li2CO3) production process and particularly the boron removal step, which currently employs a recirculated stream. This recirculated stream is a liquor with low boron content but rich in lithium, currently being wasted. In this process, the recirculating stream is substituted with a freshwater stream. Boron is re-extracted from the loaded organic stream to form an input stream for a boric acid process. Under certain operational conditions, the formation of emulsions was observed; due to this, the analysis of emulsion formation involved controlling the pH of each sample, which lead to the development of a procedure to prevent such formations. From this analysis, it was determined that emulsions form in water with pH values below 1.3 and above 6.9. In addition, a speciation analysis showed that the concentrations of the H2BO3− and H+ species influence the formation of emulsions. The mass balance of the process showed that by replacing the recirculated stream, boron recovery of 89% was achieved, without the need to add new stages or equipment. [ABSTRACT FROM AUTHOR]

The data gap in food safety regulations have created misinformation leading to the rejection of commodities for trade. The evidence presented is the local regulation of arsenic in sea produce which is based on total arsenic, tAs, instead of toxic inorganic arsenic, iAs. Furthermore, tAs data in animal origin seafood has been widely proven to be dominated by the non-toxic Arsenobetaine, AsB. Therefore, if arsenic regulatory limit was set based only on tAs without reference to iAs data, seafood products might be wrongfully rejected for trade because of non-compliance to tAs limit. We provided analysis of tAs and iAs of 14 local prawn and shrimp commodities from three shrimp/prawn sector namely aquaculture (n = 3), capture (n = 5) and processed (n = 6) using effective extraction, as well as, a fit-for-purpose analytical method for iAs. A HVG-AAS method was developed and validated for iAs with LoQ of 1.6 ppb, analytical range of 0–6 ppb, repeatability RSDr of 0.5–3.1 %, coefficient of determination R2 of 0.9975, and percentage recovery of 90.9 %, while an existing method using ICP-MS was used to verify the tAs. Based on the AOAC Official Method 999.10 2005 with minor adjustments, seafood samples were digested with concentrated nitric acid and hydrogen peroxide under pressure in a closed vessel heated by a microwave digester. An additional step for iAs determination was necessary to ensure compatibility in HVG-AAS analysis. Further subdivision of the aquaculture and capture samples was done by dividing them into 3 fractions, namely head, flesh and peel. Comparison of tAs in all the three fractions indicated that for aquaculture sector, the highest tAs were found in the flesh (2nd highest in % weight) whereas for the capture sector, the highest amount of tAs correlated with the highest % weight of the fraction. On regulatory aspects, speciation analysis on the iAs indicated samples with quantifiable iAs value were in-compliance despite tAs were initially found to be higher than the national limits. Risk assessment of iAs indicated there were no risk for human daily intake based on the BDML0.5 value of 3.0 μg/kg b.w per day for an average 70 kg man. All findings concluded the need for doing arsenic speciation analysis of iAs along with tAs for routine monitoring of prawn/shrimp samples and to revise the local limits from tAs to iAs particularly for seafood commodities.

Speciation analysis is a relevant topic since the (eco)toxicity, bioavailability, bio (geo)chemical cycles, and mobility of a given element depend on its chemical forms (oxidation state, organic ligands, etc.). The reliability of analytical results for chemical species of elements depends mostly on the maintaining of their stability during the sample pretreatment step and on the selectivity of further separation step. Solid-phase extraction (SPE) is a matter of choice as the most suitable and widely used procedure for both enrichment of chemical species of elements and their separation. The features of sorbent material are of great importance to ensure extraction efficiency from one side and selectivity from the other side of the SPE procedure. This review presents an update on the application of polymeric materials in solid-phase extraction used in nonchromatographic methods for speciation analysis. [ABSTRACT FROM AUTHOR]

This study reports the development and validation of a new analytical method for simultaneous speciation analysis of Se and Hg in fish muscle. For this purpose, four Se species (selenite/Se(IV), selenate/Se(VI), selenomethionine/SeMet, and selenocysteine/SeCys) and two Hg species (inorganic mercury/iHg and methylmercury/MeHg) were extracted simultaneously by microwave-assisted enzymatic hydrolysis and then separated by HPLC in less than 15 min by using a column with both anion and cation exchange mechanisms and a mobile phase consisting of a mixture of methanol 5% (v/v), 45 mM HNO3, 0.015% 2-mercaptoethanol, and 1.5 mM sodium 3-mercapto-1-propanesulfonate. The separated species of Hg and Se were detected online by inductively coupled plasma-mass spectrometry (ICP-MS). The speciation analysis method was validated by means of the accuracy profile approach by carrying out three series of measurements in duplicate on three different days over a time-span of 3 weeks. The limits of quantification (LOQ) are in the range of 0.010–0.013 mg/kg wet weight (ww) for all selenium species, except for Se(IV) (0.15 mg/kg ww), while the coefficient of variation in terms of intermediate reproducibility (CVR) was < 7%. The LOQ for MeHg was 0.006 mg/kg ww, while the CVR was 3%. The method was successfully applied to the analysis of muscle samples from four different fish species: rainbow trout, tuna, swordfish, and dogfish. [ABSTRACT FROM AUTHOR]

Introduction: Rice genomescontain endogenous viral elements homologous to rice tungro bacilliform virus (RTBV) from the pararetrovirus family Caulimoviridae. These viral elements, known as endogenous RTBV-like sequences (eRTBVLs), comprise five subfamilies, eRTBVL-A, -B, -C, -D, and -X. Four subfamilies (A, B, C, and X) are present to a limited degree in the genomes of the Asian cultivated rice Oryza sativa (spp. japonica and indica) and the closely related wild species Oryza rufipogon. Methods: The eRTBVL-D sequences are widely distributed within these and other Oryza AA-genome species. Fifteen eRTBVL-D segments identified in the japonica (Nipponbare) genome occur mostly at orthologous chromosomal positions in other AA-genome species. The eRTBVL-D sequences were inserted into the genomes just before speciation of the AA-genome species. Results and discussion: Ten eRTBVL-D segments are located at six loci,whichwere used for our evolutionary analyses during the speciation of the AA-genome species. The degree of genetic differentiation varied among the eRTBVL-D segments. Of the six loci, three showed phylogenetic trees consistent with the standard speciation pattern (SSP) of the AA-genome species (Type A), and the other three represented phylogenies different from the SSP (Type B). The atypical phylogenetic trees for the Type Bloci revealed chromosomeregion--specific evolution among the AA-genome species that is associated with phylogenetic incongruences: complex genome rearrangements between eRTBVL-D segments, an introgression between the distant species, and low genetic diversity of a shared eRTBVL-D segment. Using eRTBVL-Das an indicator, this study revealed the phylogenetic incongruence of local chromosomal regions with different topologies that developed during speciation. [ABSTRACT FROM AUTHOR]

Iron, a crucial element in our environment, plays a vital role in numerous natural processes. Understanding the presence and concentration of iron in the environment is very important as it impacts various aspects of our planet's health. The on-site detection and speciation of iron are significant for several reasons. In this context, the present work aims to evaluate the applicability of voltammetry for the on-site determination of iron and its possible speciation using a portable voltammetric analyzer. Voltammetry offers the advantage of convenience and cost-effectiveness. For iron (III) determination, the modification of a glassy carbon electrode (GCE) with an antimony-bismuth film (SbBiFE) using the acetate buffer (pH = 4) as a supporting electrolyte was used. The technique adopted was Square Wave Adsoptive Cathodic Stripping Voltammetry (SW-AdCSV), and we used 1-(2-piridylazo)-2-naphthol (PAN) as the iron (III) ligand. Linearity, repeatability, detection limit, and accuracy were determined using synthetic solutions; then, a Standard Reference Material (SRM) of 1643f Trace Elements in Water (iron content: 93.44 ± 0.78 µg L−1) was used for validation measurements in the real matrix. the accuracy of this technique was found to be excellent since we obtained a recovery of 103.16%. The procedure was finally applied to real samples (tap, lake, and seawater), and the results obtained were compared via Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The amount of iron found was 207.8 ± 6.6 µg L−1 for tap water using voltammetry and 200.9 ± 1.5 µg L−1 with ICP-OES. For lake water, 171.7 ± 3.8 µg L−1, 169.8 ± 4.1 µg L−1, and 187.5 ± 5.7 µg L−1 were found using voltammetry in the lab both on-site and using ICP-OES, respectively. The results obtained demonstrate the excellent applicability of the proposed on-site voltammetric procedure for the determination of iron and its speciation in water. [ABSTRACT FROM AUTHOR]

Bottom sediments were tested in order to determine the possibility of immobilization of heavy metals with the use of natural sorbents, chitosan and bentonite. The content of Cu, Zn, Cd and Pb was determined, and speciation analysis was performed using the sequential Tessier methodology. The use of sorbents clearly changes the speciation forms of all tested heavy metals by comparing the distribution of metals before and after the application of the sorbent for both chitosan and bentonite. The addition of natural sorbents affect the immobilization of metals deposited in bottom sediments of water reservoirs. However, the behavior of metals in the presence of sorbents results from their properties and the nature of the sorbent. The positive effect of sorbents on metal immobilization was not observed in every case. The addition of the tested sorbents in the case of cadmium caused an increase in the content of Cd in the mobile fractions, for Zn, Pb and Cu, stronger binding of metals was found in the stable fractions IV and V. Chitosan stabilized metals more strongly than bentonite, which moved Zn, Pb and Cu to the first mobile fraction. [ABSTRACT FROM AUTHOR]

Understanding the prevalent form of platinum (Pt) based antineoplastic agents, used in chemotherapy, is of importance to develop a remediation strategy that restricts aquatic exposure. The speciation of Pt-based compounds was measured in actual patients’ urine using hydrophobic interaction liquid chromatography (HILIC) equipped with an ICP-MS detector. Carboplatin showed poor metabolization and intact excretion 11 h after administration, whereas cisplatin underwent a rapid aquation in the first 7 h. To compare, the in vitro degradation rate of cisplatin, carboplatin and oxaliplatin was determined in synthetic human urine, mimicking true environmental conditions. The fraction of intact molecules was measured at regular intervals following incubation at 37 °C, resulting in degradation rate constants. The chemical stability was highest for carboplatin (k = 0.0143 ± 0.0012 min−1), versus faster degradation of oxaliplatin and cisplatin by exponential decay with k1 of 0.0026 ± 0.0001 min−1 and k2 = 5.59 ± 0.46 × 10−6 min−1, respectively. These kinetic parameters can serve as input to further expand modelling databases and improve the predictive power of speciation software to estimate eco-toxicity risks. Considering the strong residual cytotoxicity of the platinum antineoplastic molecules following renal clearance and human excretion, the contaminants are of high environmental concern and offer potential for metal recovery using advanced treatment steps. In such water treatment processes, especially carboplatin, above all cancerostatic platinum compounds, should be addressed since it is more persistent in the aquatic environment.

Application of tetramethylammonium hydroxide for the treatment of samples prior to elemental analysis over the last five years is approached in this review article. Characteristics and properties of this reagent are described for a better understanding of the treatment process. Its effect on analyte measurements performed by atomic spectrometry techniques (flame and graphite furnace atomic absorption spectrometry, atomic fluorescence spectrometry, inductively coupled plasma optical emission spectrometry and, inductively coupled plasma mass spectrometry) is discussed, mainly the possibilities of physical interferences. Ways of using the reagent in sample preparation, such as incubation at room temperature, use of ultrasound energy, microwave energy, among others, will be discussed, in addition to the use of the reagent in speciation and nanoparticles analyses. Tetramethylammonium hydroxide has proven to be a viable alternative in the treatment of samples that can improve the performance of methods based on atomic spectrometry in the determination of elements of great interest to society.

Objective: Four arsenic species of arsenic in aquatic products were analyzed using ultrasonic-assisted extraction combined with high performance liquid chromatography-atomic fluorescence spectrometry （HPLC-AFS）. Methods: Four arsenic compounds were extracted ultrasonically from the samples using 50%（v/v） methanol-aqueous solution as extraction solvent. The chromatographic separation was performed on Hamilton PRP-X100 anion exchange column using a mixture of 15 mmol/L ammonium dihydrogen phosphate solution with the pH adjust to 6.0 as the mobile phase. Results: Under the optimized conditions, there were good linear relationships in the range of 0~100 μg/L for four arsenic compounds, with correlation coefficients all above 0.998. The limit of detection （LODs） of four arsenic species MMA, DMA,As（Ⅲ）,As（Ⅴ）were 0.82, 0.94, 1.10, 0.78 μg/L respectively. The relative standard deviations were in the range of 0.8%~3.7%. The recoveries ranged from 86.0% to 110.0%. Conclusion: This method is simple, accurate, sensitive, and low reagent consumption costs, can be used for the determination of the arsenic species in aquatic products.

Selenium (Se) is an essential micronutrient that plays an important role in animal and human development and physiological homoeostasis. This review surveys the role of Se in the environment, plants and animal bodies, and discusses data on Se biofortification with different sources of supplementation, from inorganic to organic forms, with special focus on Se-enriched yeast (Se-yeast). Although Se-yeast remains one of the main sources of organic Se, other emerging and innovative sources are reviewed, such as Se-enriched insects and Se-nanoparticles and their potential use in animal nutrition. Se-enriched insects are discussed as an option for supplying Se in organic form to livestock diets. Se-nanoparticles are also discussed, as they represent a more biocompatible and less toxic source of inorganic Se for animal organisms, compared to selenite and selenate. We also provide up to date information on the legal framework in the EU, USA, and Canada of Se that is contained in feed additives. From the scientific evidence available in the literature, it can be concluded that among the inorganic forms, sodium selenite is still one of the main options, whereas Se-yeast remains the primary organic form. However, other potential sources such as Se-enriched insects and Se-nanoparticles are being investigated as they could potentially combine a high bioavailability and reduced Se emissions in the environment.

Antimony (Sb) contamination poses significant environmental and health concerns due to its toxic nature and widespread presence, largely from anthropogenic activities. This study addresses the urgent need for an accurate speciation analysis of Sb, particularly in water sources, emphasizing its migration from polyethylene terephthalate (PET) plastic materials. Current methodologies primarily focus on total Sb content, leaving a critical knowledge gap for its speciation. Here, we present a novel analytical approach utilizing frontal chromatography coupled with inductively coupled plasma mass spectrometry (FC-ICP-MS) for the rapid speciation analysis of Sb(III) and Sb(V) in water. Systematic optimization of the FC-ICP-MS method was achieved through multivariate data analysis, resulting in a remarkably short analysis time of 150 s with a limit of detection below 1 ng kg−1. The optimized method was then applied to characterize PET leaching, revealing a marked effect of the plastic aging and manufacturing process not only on the total amount of Sb released but also on the nature of leached Sb species. This evidence demonstrates the effectiveness of the FC-ICP-MS approach in addressing such an environmental concern, benchmarking a new standard for Sb speciation analysis in consideration of its simplicity, cost effectiveness, greenness, and broad applicability in environmental and health monitoring.

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Background. Worldwide, there is a rapid increase in the number of people suffering from various forms of carbohydrate and lipid metabolism disorders. Modern studies show that the transport, distribution, excretion and accumulation of chemical elements in these types of metabolic disorders change in different ways and affect the further functional state of the body differently.The aim. To evaluate the level of macro- and microelements in the blood serum and liver, as well as the content of metal-ligand forms of zinc in the blood serum of a Wistar rat in a high-calorie diet.Materials and methods. Thirty male rats were selected for the experiment, from which two groups were formed: control (n = 15) and experimental (n = 15). The animals of the control group received the basic diet (270 kcal/100 g), and the animals of the experimental group received a high-calorie diet. During the experiment, the caloric content of the diet of the experimental group gradually increased from the caloric content of the total diet. During the study, body weight, biochemical parameters of blood and urine were evaluated. The analysis of macro- and microelements in the samples was carried out using inductively coupled plasma mass spectrometry. Determination of the content of individual zinc compounds in blood serum was carried out using a combination of a chromatograph and a mass spectrometer.Results. It was found that a high-calorie diet led to a decrease in the level of iron, chromium, iodine, zinc, potassium, calcium, and an increase in vanadium in blood serum. In the liver, there was a decrease in the level of lithium and an increase in the level of calcium, vanadium, chromium, iron, zinc, cobalt. When assessing the chemical forms of zinc in the blood serum, a percentage increase in the albumin fraction was recorded against the background of a decrease in amino acid complexes and low-molecular-weight forms of zinc.Conclusion. The data obtained suggest that a high-calorie diet leads to an imbalance of chemical elements, which can serve as one of the triggers for dysregulation of a number of physiological functions of the body.

The analysis of iodine content in kelp is mainly focused on determining total iodine content, which lacks a rapid and sensitive analytical method for iodine species corresponding to iodate, iodide, monoiodotyrosine (MIT), and diiodo-tyrosine (DIT). Based on exploring the pretreatment methods of enzymatic hydrolysis of kelp, a rapid determination method of high-performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for different iodine species existed in kelp samples was established. The pretreatment method is trypsin hydrolysis of kelp samples treated at 50°C for 10 hours, then the extraction solution was obtained by centrifugation, and filtration was proved for the first time. A high-efficiency separation anion-exchange column (Dionex IonPac AS-14) for iodate, iodide, MIT, and DIT with 0.1 mol·L−1(NH4)2CO3 solution at pH = 9 as a mobile phase, a flow rate of 0.8 mL·min−1 for the first 1500 s, and 1.2 mL·min−1 for the last 1800 s was confirmed. The linear ranges of the standard calibrations on four iodine species are 1.0–150 μg·L−1, and the detection limits are 1.62, 1.02, 1.59, and 2.55 μg·L−1, respectively, while the RSD values of four iodine species are all less than 2%. Under the optimized conditions, the proposed method was successfully applied for the speciation analysis of iodine in kelp samples. [ABSTRACT FROM AUTHOR]

The accumulation of potentially toxic elements (PTEs) in water, soil and vegetables can pose a severe threat to the respective organisms and lead to human health risks upon exposure. Water, soil and vegetable samples were collected from the Mokolo River and its vicinity. Total concentration quantification and speciation analysis of chromium (Cr) and arsenic (As) were performed using inductively coupled plasma-mass spectrometry (ICP-MS) and high-performance liquid chromatography hyphenated to inductively coupled plasma-mass spectrometry (HPLC-ICP-MS), respectively. The total concentrations of Cr and As were below the maximum permissible levels (MPLs) set by the World Health Organization (WHO) and South Africa's Department of Water Affairs and Forestry (DWAF) for drinking water. The soil quality guideline value of 64.0 µg/g for Cr was surpassed in most sites and posed a great risk to the vegetables growing in it, whereas the guideline value of 12.0 µg/g for As was surpassed in one sampling site. The observed high concentrations in soil could be linked to the use of fertilizers and atmospheric deposits introduced through coal burning by power stations. In vegetables, the total Cr concentration surpassed the recommended MPL of 0.5 µg/g, rendering the vegetables unsafe for human consumption. Concentrations ranging from 197 to 1180 ng/g and 374 to 17400 ng/g were detected for Cr(VI) and Cr(III), respectively. The consumption of vegetables containing high levels of Cr and As would result in health risks in adults and children as the total hazard quotient (THQ) exceeded 1. The consumption of some vegetables particularly by children could cause serious health risks as the THQ > 10 was observed for some Cr-contaminated vegetables. The incremental lifetime cancer risk (ILCR) threshold of 1 × 10−4 was exceeded, indicating that the overall consumption of vegetables had high cancer risks for adults and children. This study suggests that the consumption of vegetable samples would lead to health risks in the population. [ABSTRACT FROM AUTHOR]

BACKGROUND: As the main source of iodine intake, water is of practical significance to detect the content of iodide accurately. At present, the common methods for the analysis of iodide in water samples include ion chromatography, gas chromatography, colorimetry, spectrophotometry. The analysis results of different methods can be affected by the actual sample matrix and experimental conditions. Our project team organized 38 laboratories to determine the content of iodide in natural water samples by ion chromatography, starch spectrophotometry, catalytic reduction spectrophotometry, and inductively coupled plasma-mass spectrometry (ICP-MS), the results showed that there were significant differences among the measured values by different methods, and the data were obviously dispersed. OBJECTIVES: To discuss the reasons for the differences between the results of different methods and give suggestions on the selection of iodide analysis methods under different conditions, based on the principles and conditions of each method. METHODS: Four analysis methods, including ion chromatography, starch spectrophotometry, catalytic reduction spectrophotometry, and ICP-MS, were used to determine the content of iodide of the groundwater sample by 38 laboratories. High performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP)MS) was used to determine the content of iodide by our own laboratory. RESULTS: (1) HPLC-ICP-MS can be used to effectively separate iodide and iodate ions in water samples. Through the quality control of the experimental process by blank samples, standard reference materials and replicate samples, the analytical results of this method were accurate and reliable. The determination results of iodide in JSH-2 samples were 78.32μg/L. 　　(2) The determination values of iodide by ion chromatography (83.38μg/L) were consistent with those by HPLC-ICP-MS (78.32μg/L). However, the data of ion chromatography between different laboratories were obviously dispersed. The determination values of iodide by the starch spectrophotometry (92.95μg/L), catalytic reduction spectrophotometry (101.84μg/L) and ICP-MS (103.13μg/L) were higher than those by HPLC-ICP-MS. 　　(3) The reasons for the differences between the results of different methods were discussed, based on the principles and conditions of each method: 　 　① The determination results of ion chromatography may be affected by the selection of experimental conditions, such as sample pretreatment, chromatographic column and detector, and other interfering components. 　 　② It is not considered whether there is iodate ion in the sample itself in the starch spectrophotometry. Therefore, when there are iodate ions in the water sample, the determination result is actually the total content of inorganic iodine. 　　③ The standard working curve of the catalytic reduction spectrophotometry is bent downward as a whole and does not show a good linear relationship. Therefore, when the response value of iodide is high, the concentration value will be high. 　　④ ICP-MS is only used to determine the total content of elements, and cannot be used for elemental speciation analysis. There are iodate ions in the samples of this experiment, so the determination results of ICP-MS should be the total content of iodine, rather than the content of iodide. CONCLUSIONS: When iodate ions are present in water samples, starch spectrophotometry and ICP-MS may lead to a high result of iodide determination. Among them, starch spectrophotometry is usually suitable for samples with an iodide concentration of 25-500μg/L, and ICP-MS can be combined with other separation techniques to improve method selectivity. When iodate ions are present in water samples, catalytic reduction spectrophotometry and ion chromatography can be used to analyze the concentration of iodide, but the influence of sample concentration level, matrix interference components, experimental conditions and other factors should be considered. HPLC-ICP-MS can be applied to the quantitative analysis of iodine species in water samples, which can avoid the influence of iodate ions on the accuracy of iodide determination results. [ABSTRACT FROM AUTHOR]

As a form of new emerging pollutant, antibiotics have been detected in soil, surface water, groundwater, sediment and other different environmental media. As a major country in the production and usage of antibiotics, China's production and usage are increasing year by year. However, most antibiotics used for humans or animals cannot be fully absorbed and metabolized and will enter the environment in the form of prototypes or metabolites through waste and wastewater accumulating in soil and leaching into groundwater. Antibiotics entering the environment may affect microbial ecology, produce resistance genes, and even threaten human health. Compared with surface water, polluted groundwater is hidden, lagging and difficult to recover. The pollution of antibiotics in groundwater, as the main source of drinking water, has attracted much attention.So far, the research on antibiotics in China is still mainly on surface water and soil, and there are few observations on antibiotics in groundwater. In order to systematically grasp the current pollution situation of antibiotics in groundwater in China, relevant literature on antibiotics in groundwater from 2012 to 2021 is reviewed in this paper. Twenty-eight antibiotics detected more than 100 times in environmental media in China were selected as target antibiotics, and the detected concentrations were summarized and analyzed. It was found that the concentrations of 28 antibiotics commonly detected in groundwater varied by more than 4 orders of magnitude, from 0.1ng/L to more than 1000ng/L. The most frequently detected antibiotics were norfloxacin, ofloxacin, sulfamethoxazole, sulfadiazine, enrofloxacin, and erythromycin. Through comparative analysis of the detection of antibiotics in various places, it can be seen that the concentration of antibiotics in groundwater is controlled by the properties of antibiotics, the location of pollution sources, hydrogeological structure and the amount of usage and emissions. From the perspective of spatial distribution, sulfonamide antibiotics are the most detected in northeast China, quinolones are the most detected in North and East China, quinolones and tetracyclines are the most detected in southwest China, and the research on antibiotics in groundwater in northwest China is relatively low. So far, restrained by the detection limits and detection types of the analysis methods, a comprehensive investigation and evaluation of antibiotics in groundwater is not possible.Due to the wide variety of antibiotics, their different structures lead to different physical andchemical properties. They exist in trace concentrations in the complex environment media, which also affects the accuracy of their qualitative and quantitative analysis. Therefore, the establishment of a sensitive and specific multi-component simultaneous analysis method has been a key issue for antibiotics research. The analysis methods of antibiotics are summarized, which are divided into qualitative analysis methods and quantitative analysis methods. The principle, advantages, disadvantages and application range of several antibiotic analytical methods are presented. These methods include microbial inhibition method (MIT), thin layer chromatography (TLC), gas chromatogram-mass spectrometry (GC-MS), high-performance liquid chromatogram-nuclear magnetic resonance (HPLC-NMR) and liquid chromatogram-mass spectrometry (LC-MS). Liquid chromatogram-mass spectrometry (LC-MS) is the most commonly used method for antibiotic analysis because of its high sensitivity, low detection limit and simultaneous determination of multiple antibiotics. With the rapid development of antibiotic analysis methods, some antibiotics in groundwater can be accurately quantified by using HPLC-MS/MS and other technologies. However, the number of antibiotics that can be analyzed and identified at one time is still limited. The research group of authors has established the qualitative spectrum library of common drugs by UPLC-MS/MS. In the future, the types of antibiotics that can be qualitatively identified in the spectrum library can be expanded by adding the mass spectrum information of antibiotics. Under specific conditions, the spectrum library can be used to carry out semi-qualitative identification of antibiotics in groundwater. At present, the commonly used quantitative detection methods include enzyme-linked immunoassay, capillary electrophoresis, and liquid chromatography-mass spectrometry. Compared with the other two methods, liquid chromatography-mass spectrometry has the advantages of high sensitivity, good selectivity and accurate quantitative ability. It is commonly used for the detection of trace antibiotics in reported water samples.Antibiotics exist in the environment at trace levels and the matrix of environmental samples is complex, so the pretreatment process, including antibiotic separation, purification and concentration, often becomes the key step of determination. For example, the samples to be tested should be adjusted to an appropriate pH to enhance the enrichment of target antibiotics on HLB columns, and Na2EDTA should be added to inhibit its complexation with calcium and magnesium and other metal ions in groundwater. The accuracy of antibiotic determination will be improved, and the detection limit will be lowered for water samples by solid phase extraction and the subsequent concentration process. In addition to the detection limit and recovery rate of antibiotics affected by the analytical instrument, the presence states of antibiotics in water samples will also affect the accuracy and precision.Antibiotics may exist in the ionized state, complex state, adsorption state and other forms in groundwater. At different pH values, antibiotics may exist in neutral, cationic, anionic, orzwitterionic forms. When it coexists with metal ions, complexation reaction will occur under certain conditions to form antibiotic-metal complex which will reduce the peak area to a certain extent or cause tailing phenomenon on the reverse analytical column. The formation of the complex may also change the environmental behavior (migration, transformation, toxicity, etc.) and ecological effects of antibiotics. In addition, the analysis of antibiotics in different adsorption states can be used to evaluate the differences in microbial killing effects of different adsorption forms, especially the differences in ARG production and spreading. This will be helpful for accurately evaluating the potential effects on the environment or human beings and effectively controlling the risks of antibiotics in environmental media. Therefore, the existing form analysis of antibiotics is of great significance for the further accurate determination of antibiotics and the evaluation of environmental effects.Up to now, limited by the detection limits and detected types of antibiotics in analytical methods, there has not been a comprehensive national-scale investigation and evaluation of antibiotics in groundwater in China. Only by clarifying the concentration level and spatial distribution of antibiotic pollution in China's groundwater can it help to understand the contents of relevant laws and regulations on new emerging pollutants and support the establishment of a regulatory framework for natural resources and the environment. In conclusion, optimizing qualitative and quantitative detection methods, analyzing different existing forms of antibiotics, comprehensively investigating antibiotics in groundwater, and scientifically evaluating the relationship between antibiotic forms and ecotoxicological effects are the main contents of antibiotics research in groundwater in the future.

Arsenic is a poisonous semi-metal (metalloid) and has been identified as a human carcinogen. Arsenic poisoning can cause a variety of health damage to the human body. Arsenic can exist in both inorganic and organic forms. It is generally considered that inorganic arsenic is more toxic than organic arsenic. Arsenolipids are organic arsenic and widely exist in tissues of marine organisms. Arseniolipids have been previously thought to be extremely low toxic. With the progress and development of science and technology in recent years, intensive research has been conducted on arsenolipids, and the speciation analysis and toxicity evaluation of arsenolipids have gradually become a hot spot. At present, there are three known species of arsenolipids, namely arsenic-containing fatty acids (AsFAs), arsenic-containing hydrocarbons (AsHCs) and arsenic-containing phospholipids (AsPLs), which differ in their toxicity. However, due to the complex speciation pattern, low bioavailability and low content of arsenolipids, and the difficulty to extract and detect them, the mechanism of arsenolipid toxicity remain unclear. Therefore, this paper reviews the latest progress in the methods for speciation analysis and toxicity evaluation of arsenolipids in marine organisms, with the aim to provide an inspiration for further elucidating the speciation, toxicity, and human health risk of arsenolipids.

Mobility and bioavailability of radionuclides in the environment strongly depend on their aqueous speciation, adsorption behavior and the solubility of relevant solid phases. In the present context, we focus on naturally occurring Th-232 at a location in central Sri Lanka presenting high background radiation levels. Four different soil samples were characterized using X-ray Absorption Spectroscopy (XAS) at the Th L3-edge (16.3 keV), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) spectroscopy. X-ray Absorption Near Edge Structure (XANES) spectra are applied as a fingerprint indication for Th existing in different chemical environments. Linear combination fitting (LCF) of the Extended X-ray Absorption Fine Structure (EXAFS) data involving reference Th-monazite (phosphate) and thorianite (oxide) compounds suggested that Th is mostly present as Th-phosphate (76 ± 2%) and Th-oxide (24 ± 2%), even though minor amounts of thorite (silicate) were also detected by SEM–EDX. Further studies on selected individual particles using micro-focus X-ray Fluorescence (μ-XRF) and micro-X-ray Absorption Spectroscopy (μ-XAS) along with SEM–EDX elemental mapping provided information about the nature of Th-bearing mineral particles regarding mixed phases. This is the first study providing quantitative and XAS based speciation information on Th-mineral phases in soil samples from Sri Lanka. [ABSTRACT FROM AUTHOR]

IntroductionAnalysis of the composition of yogurt alternatives (YAs) during fermentation provides critical information for evaluating its quality and nutritional attributes.MethodWe investigated the effects of homotypic (HO) and heterotypic (HE) lactic acid bacteria on the nutritional and mineral bioavailabilities of soybean YA (SYA) during fermentation.ResultThe acidic amino acid (Glu, Asp) and organic acid contents in HO-fermented YA were increased from 2.93, 1.71, and 7.43 mg/100 g to 3.23, 1.82, and 73.47 mg/100 g, respectively. Moreover, both HO and HE lactic acid bacteria fermentation enhanced mineral absorptivity. They altered the molecular speciation of minerals from a large molecular type (2,866 Da) to a small molecular type (1,500 Da), which was manifested in a time-dependent manner. Furthermore, YA substantially increased the bone mass in a zebrafish osteoporosis model, further highlighting the potential of lactic acid bacterial fermentation for mineral bioavailability.DiscussionThis study provides a foundation for understanding the effects of fermentation conditions on the composition and bioavailability of minerals in YA and can assist in its production.

BACKGROUND The development of urban industrialization causes soil heavy metal pollution and other environmental problems. Studies have shown that the damage caused by soil heavy metals to the ecological environment is not only related to the total content, but also depends on the speciation of heavy metals. OBJECTIVES To investigate the content characteristics, speciation and risk status of heavy metals in soil of a city in the Hetao Plain. METHODS 52 soil samples were collected from different functional areas of the Hetao Plain, heavy metals were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS), atomic fluorescence spectrometry (AFS) and other analytical methods to study the total content and speciation. The ecological risk of soil heavy metals was evaluated using the RAC risk assessment method. RESULTS The results showed that the contents of heavy metal elements (except As) in surface soil were higher than the background values in the Hetao Plain, the variation coefficients of Pb, Cr, Mn, Cd and Zn were large and the spatial distribution was not uniform, which were significantly affected by human activities. The heavy metal content in the industrial area exceeded the background value, especially Cd (5.83 times of background value) and Pb (3.58 times of background value). Road heavy metal contents were also significantly higher than the background value, Cd was nearly 4 times the background value. Except for Cd in industrial areas, other heavy metals were mainly in residual fraction. The residual fractions of Cr, Ni, Cu and As were more than 70%. The residual fraction of Cd in each functional region accounted for about 30%. RAC risk assessment results showed that Cd and Pb in industrial areas reached the high-risk level. CONCLUSIONS The research results provide scientific basis for identifying the potential environmental risks in urban area soil and proposing effective prevention.

Heavy metals (HMs) pollution in the environment is a persistent issue and draws public attention constantly. However, there is little research assessing the pollution level of HMs in the Henan section of the Yellow River although the river is one of the most important water supply rivers in Henan province. In this research, the fraction contents of six HMs in the Henan section of the Yellow River were investigated by adopting the European Community Bureau of Reference (BCR) sequential extraction procedure. Moreover, the potential health risk caused by HMs was evaluated by adopting both the geo-accumulation index (Igeo) and ecological hazard index method. The results indicate the presence of a light HM pollution level in the Yellow River generally. However, the health risk caused by Cd cannot be neglected. Fraction analysis indicates that the content of the B2 fraction is high, which needs more attention. Overall, branch afflux might be one of the important pathways through which anthropogenic activities influence the Yellow River. The results of both the Igeo and ecological hazard index indicate that the potential health risk caused by HMs is low in the Yellow River, and the Yellow River protection policies implemented by Henan province may be the underlying reason. HIGHLIGHTS In this study, the content of six heavy metals in the Yellow River of the Henan section was investigated by adopting the BCR method.; The concentration of Cd was significantly higher than the background value.; The B1 fraction of Mn and B2 fraction of Pb were high, and the potential health risk should receive more attention.;

The present study describes a method for the determination of As (III) and As (V) in copper electrolytes. The method is based on the separation of As (III) from a copper electrolyte by triple liquid-liquid extraction using a non-polar organic solvent in a medium of 10-12 mol L–1 HCl. The extract contains As (III) and the raffinate-As (V), respectively. As(III) specie can be re-extracted from the organic solvent through the water. Analyzes of the concentration of As in the re-extract and raffinate were performed by ICP-OES spectroscopic method. The average recovery of arsenic by the proposed method is about 99%. Repeatability was estimated with RSD (n = 6). Selectivity and accuracy were proven by the standard addition method. The relative error for restoring the standard addition of As (III) is about 0.3%. The speciation method analysis could be applied for determination of the arsenic species in the analytical quality control of refined copper in copper tanks in the production of copper cathodes.

Gut microbiota provides protection against arsenic (As) induced toxicity, and As metabolism is considered an important part of risk assessment associated with soil As exposures. However, little is known about microbial iron(III) reduction and its role in metabolism of soil-bound As in the human gut. Here, we determined the dissolution and transformation of As and Fe from incidental ingestion of contaminated soils as a function of particle size (

To explore the distribution characteristics and degree of pollution of heavy metals in the farmland soil around the Dachang tin polymetallic mining area in Guangxi, a total of 140 soil samples were collected around the mining area in this study. The total amount and various forms of seven heavy metals (Cu, Pb, Cd, Cr, Zn, As, and Ni) were analyzed by inductively coupled plasma mass spectrometry, and the improved continuous extraction method of heavy metal speciation analysis in the soil, the potential ecological risk index (RI), the and Nemerow evaluation index (PN) were used to evaluate pollution characteristics of the soil and the bioavailability of heavy metals. Corresponding remediation suggestions were given according to the pollution degree. The results show that the whole soil in the study area is acidic, reducing, and the content of organic matter is low. The average content of heavy metal elements is higher than the background value of Guangxi, among which Cd, Pb, and As exceed the control value and are the main elements of pollution. The speciation analysis of heavy metals in soil shows that Cd is dominated by the ion exchange form; Cu is mainly residual and in a humic acid combined form; and the rest of the elements are mainly in residual form. Among the seven heavy metals, Cd has the strongest mobility, biological toxicity, and ecological risk, followed by As, Ni, and Zn. The overall pollution level of the soil in the study area is heavily polluted (PN = 39.6), which is a very strong ecological risk level (RI = 2196.9), and the main pollutants are Pb, As, and Cd; Cd pollution is the most serious. Correlation (CA) and principal component analysis (PCA) indicate that the pollution sources of Pb, Cu, Zn, Cd, and As among the seven elements were mainly controlled by tailings accumulation, mining, and transportation, and the sources of Cr and Ni were controlled by soil-forming parent materials. Furthermore, according to the actual situation of the farmland around the mining area, two remediation suggestions are put forward: (1) use stabilization remediation technology to clean up the pollution source, such as calcium dihydrogen phosphate to reduce the bioavailability of the most polluted elements, Cd and Pb, in the soil; (2) under the concept of green environmental protection, use Typha orientalis Presl to repair the industrial and mining wasteland and some unused land. [ABSTRACT FROM AUTHOR]

Rare earth elements (REEs) are not only important strategic resources, but also have important research significance in tracing the sources of rocks, minerals, sediments, and other materials due to their unique geochemical properties. In recent years, with the increasing use of REEs in modern society, anthropogenic REEs have attracted widespread attention from scholars at home and abroad through different pathways into environmental media such as the atmosphere, water and soil. Gadolinium (Gd), one of the most widely used REEs, is commonly used as Gd - based constrast agents ( GBCAs). Since the application of GBCAs in the 1980s, their use has increased year by year. However, GBCAs are highly hydrophilic and stable, and they are difficult to remove in conventional wastewater treatment; the vast majority of them can directly enter urban and surrounding waters. Since Bau and Dulski first reported positive Gd anomalies in the Rhine River in Germany in 1996, anthropogenic Gd, an emerging contaminant, has now been detected in surface waters worldwide. However, there are relatively few studies on anthropogenic REEs, and the direct determination of them is difficult due to the constraints of detection techniques, and traditional methods for estimating anthropogenic REEs are inevitably subject to varying degrees of error. Since its introduction in the 1980s,inductively coupled plasma-mass spectrometry (ICP-MS) has shown great potential for trace multi-element analysis due to its high sensitivity, low detection limits and wide linearity range. The technique combines a plasma ion source with high ionization efficiency and a mass spectrometer with the advantages of high sensitivity, rapid multi-element detection and less mass interference compared to spectroscopy in a special interface, making it a highly efficient technique for simultaneous multi - element analysis. The development of high-precision ICP-MS and its coupling techniques, has led to a revolutionary breakthrough in the study of REEs provenance indication. The combination of highly selective separation techniques such as ion chromatography and highly sensitive ICP-MS has played an important role in the analysis of anthropogenic REEs, and the elemental speciation analysis capabilities of it make this one of the key research tools for the analysis of anthropogenic REEs. The progress of geochemical features of REEs such as isotopes in identifying material sources, resolving key processes and tracing environmental behavior, is summarized in this study, mainly including: ( 1 ) REEs fractionation patterns and isotopic features have been widely used in traditional provenance indication, and research is mainly based on REEs content or isotope information, combined with relevant mathematical and statistical models; (2) The speciation of REEs can provide an important basis for indicating anthropogenic activities, for example, due to the regional differences in the types of GBCAs used, there are obvious geographical differences in the speciation of anthropogenic REEs, with a high detection rate of macrocyclic GBCAs and a low detection rate of linear GBCAs in natural waters in regions such as Germany. On this basis, the application of ICP -MS and its coupling techniques in the source tracing of REEs is systematically reviewed, the main studies on REEs for tracing the sources of substances and indicating human activities are summarized, and the prospects for the development of source tracing of REEs are outlined. Among these analytical techniques, laser ablation multicollector inductively coupled plasma-mass spectrometry (LA-MC-ICP -MS) can be used to obtain in-situ information on the spatial distribution of the isotopic composition of REEs within samples. Hydrophilic interaction liquid chromatography coupled to inductively coupled plasma-mass spectrometry (HILIC-ICP-MS) has become an important tool for the analysis of the speciation of anthropogenic REEs in waters. To address the shortcomings of the current technical approach, a research outlook for the development of rapid and portable analytical techniques, the integration of multidimensional information for tracer studies, and the integrated consideration of the effects of human activitiesis proposed. It is worth noting that the frequency and concentration levels of anthropogenic REEs in the natural environment have increased significantly, which may affect the distribution characteristics of geogenic REEs and thus reduce the accuracy of traditional source tracing studies. Therefore, future studies need to consider whether human activities in the vicinity have significantly influenced the study area before conducting conventional provenance indication analyses. [ABSTRACT FROM AUTHOR]

As a form of new emerging pollutant, antibiotics have been detected in soil, surface water, groundwater, sediment and other different environmental media. As a major country in the production and usage of antibiotics, China’s production and usage are increasing year by year. However, most antibiotics used for humans or animals cannot be fully absorbed and metabolized and will enter the environment in the form of prototypes or metabolites through waste and wastewater accumulating in soil and leaching into groundwater. Antibiotics entering the environment may affect microbial ecology, produce resistance genes, and even threaten human health. Compared with surface water, polluted groundwater is hidden, lagging and difficult to recover. The pollution of antibiotics in groundwater, as the main source of drinking water, has attracted much attention. So far, the research on antibiotics in China is still mainly on surface water and soil, and there are few observations on antibiotics in groundwater. In order to systematically grasp the current pollution situation of antibiotics in groundwater in China, relevant literature on antibiotics in groundwater from 2012 to 2021 is reviewed in this paper. Twenty-eight antibiotics detected more than 100 times in environmental media in China were selected as target antibiotics, and the detected concentrations were summarized and analyzed. It was found that the concentrations of 28 antibiotics commonly detected in groundwater varied by more than 4 orders of magnitude, from 0. 1ng / L to more than 1000ng / L. The most frequently detected antibiotics were norfloxacin, ofloxacin, sulfamethoxazole, sulfadiazine, enrofloxacin, and erythromycin. Through comparative analysis of the detection of antibiotics in various places, it can be seen that the concentration of antibiotics in groundwater is controlled by the properties of antibiotics, the location of pollution sources, hydrogeological structure and the amount of usage and emissions. From the perspective of spatial distribution, sulfonamide antibiotics are the most detected in northeast China, quinolones are the most detected in North and East China, quinolones and tetracyclines are the most detected in southwest China, and the research on antibiotics in groundwater in northwest China is relatively low. So far, restrained by the detection limits and detection types of the analysis methods, a comprehensive investigation and evaluation of antibiotics in groundwater is not possible. Due to the wide variety of antibiotics, their different structures lead to different physical andchemical properties. They exist in trace concentrations in the complex environment media, which also affects the accuracy of their qualitative and quantitative analysis. Therefore, the establishment of a sensitive and specific multi-component simultaneous analysis method has been a key issue for antibiotics research. The analysis methods of antibiotics are summarized, which are divided into qualitative analysis methods and quantitative analysis methods. The principle, advantages, disadvantages and application range of several antibiotic analytical methods are presented. These methods include microbial inhibition method (MIT), thin layer chromatography (TLC), gas chromatogram-mass spectrometry (GC-MS), high-performance liquid chromatogram-nuclear magnetic resonance (HPLC-NMR) and liquid chromatogram-mass spectrometry ( LC-MS). Liquid chromatogram -mass spectrometry ( LC -MS) is the most commonly used method for antibiotic analysis because of its high sensitivity, low detection limit and simultaneous determination of multiple antibiotics. With the rapid development of antibiotic analysis methods, some antibiotics in groundwater can be accurately quantified by using HPLC-MS / MS and other technologies. However, the number of antibiotics that can be analyzed and identified at one time is still limited. The research group of authors has established the qualitative spectrum library of common drugs by UPLC -MS / MS. In the future, the types of antibiotics that can be qualitatively identified in the spectrum library can be expanded by adding the mass spectrum information of antibiotics. Under specific conditions, the spectrum library can be used to carry out semiqualitative identification of antibiotics in groundwater. At present, the commonly used quantitative detection methods include enzyme - linked immunoassay, capillary electrophoresis, and liquid chromatography - mass spectrometry. Compared with the other two methods, liquid chromatography-mass spectrometry has the advantages of high sensitivity, good selectivity and accurate quantitative ability. It is commonly used for the detection of trace antibiotics in reported water samples. Antibiotics exist in the environment at trace levels and the matrix of environmental samples is complex, so the pretreatment process, including antibiotic separation, purification and concentration, often becomes the key step of determination. For example, the samples to be tested should be adjusted to an appropriate pH to enhance the enrichment of target antibiotics on HLB columns, and Na2EDTA should be added to inhibit its complexation with calcium and magnesium and other metal ions in groundwater. The accuracy of antibiotic determination will be improved, and the detection limit will be lowered for water samples by solid phase extraction and the subsequent concentration process. In addition to the detection limit and recovery rate of antibiotics affected by the analytical instrument, the presence states of antibiotics in water samples will also affect the accuracy and precision. Antibiotics may exist in the ionized state, complex state, adsorption state and other forms in groundwater. At different pH values, antibiotics may exist in neutral, cationic, anionic, orzwitterionic forms. When it coexists with metal ions, complexation reaction will occur under certain conditions to form antibiotic-metal complex which will reduce the peak area to a certain extent or cause tailing phenomenon on the reverse analytical column. The formation of the complex may also change the environmental behavior (migration, transformation, toxicity, etc. ) and ecological effects of antibiotics. In addition, the analysis of antibiotics in different adsorption states can be used to evaluate the differences in microbial killing effects of different adsorption forms, especially the differences in ARG production and spreading. This will be helpful for accurately evaluating the potential effects on the environment or human beings and effectively controlling the risks of antibiotics in environmental media. Therefore, the existing form analysis of antibiotics is of great significance for the further accurate determination of antibiotics and the evaluation of environmental effects. Up to now, limited by the detection limits and detected types of antibiotics in analytical methods, there has not been a comprehensive national-scale investigation and evaluation of antibiotics in groundwater in China. Only by clarifying the concentration level and spatial distribution of antibiotic pollution in China’s groundwater can it help to understand the contents of relevant laws and regulations on new emerging pollutants and support the establishment of a regulatory framework for natural resources and the environment. In conclusion, optimizing qualitative and quantitative detection methods, analyzing different existing forms of antibiotics, comprehensively investigating antibiotics in groundwater, and scientifically evaluating the relationship between antibiotic forms and ecotoxicological effects are the main contents of antibiotics research in groundwater in the future. [ABSTRACT FROM AUTHOR]

Antimony (Sb) is an emerging contaminant, and its on-site speciation analysis is central to the accurate evaluation of its bioavailability and toxicity. The whole-cell biosensors (WCBs) for Sb(III) are promising but challenging due to the lack of Sb(III)-specific recognition components. Here, we constructed a novel Sb(III)-specific WCB using an Sb(III) transcriptional regulator (antR) and its cognate promoter (Pant). To prevent the promoter leakage of Pant, an additional regulatory gene, antR, was inserted downstream of the Sb(III)-inducible promoter, improving the sensitivity of the WCB by an order of magnitude and reaching the detection limit at 0.009 μM, which is lower than the WHO drinking water standard of Sb. Moreover, the WCB with double antR showed a high specificity toward Sb(III) compared with interfering ions at 3 orders of magnitude higher concentrations. This WCB was capable of measuring Sb(III) bioavailability in natural waters and sediments on-site, and its results were not statistically different from the chemical analysis. The insights gained from this work demonstrate that the addition of regulatory genes prevents promoter leakage and improves the sensitivity of WCBs in field applications. [ABSTRACT FROM AUTHOR]

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Mercury (Hg) is a highly toxic and persistent heavy metal pollutant. The acid mine drainage (AMD) environment in sulfide-mining areas is a typical Hg pollution source. In this paper, the transformation of Hg2+ during anaerobic S0 reduction by an AMD environmental enrichment culture was studied by multiple spectroscopic and microscopic techniques. The experimental results showed that the microbial S0 reduction of the AMD enrichment culture was significantly inhibited in the presence of Hg2+. The results of cell surface morphology and composition analysis showed that there was obvious aggregation of flocculent particles on the cell surface in the presence of Hg2+, and the components of extracellular polymeric substances on the cell surface changed significantly. The results of surface morphology and C/S/Hg speciation transformation analyses of the solid particulate showed that Hg2+ gradually transformed to mercuric sulfide and Hg0 under anaerobic S0 reduction by the AMD enrichment culture. The microbial community structure results showed that Hg2+ significantly changed the enrichment community structure by decreasing their evenness. The dominant microorganisms with S0 reduction functions are closely related to mercury transformation and are the key driving force for the transformation of substrate solid particulate and cellular substances, as well as the fixation of Hg2+. [ABSTRACT FROM AUTHOR]

The properties of metal(loid)s in the environment are mainly determined by their chemical forms. The chemical forms of metal(loid)s affect their possible chemical and biochemical reactions, toxicity, mobility, and bioavailability in the environment. Sequential chemical extraction (SCE) has been successfully used to clarify the chemical forms of soil metal(loid)s. However, quite a few SCE procedures have been applied for speciation analysis of plant samples; there is no systematic discussion in such a field. The current review deals with the SCE of plant metal(loid)s, and compares the extraction procedures and the extractants in different SCE methods. It has been found that some chemical forms are unreliable for plant SCE analyses. The forms can be the phosphates or oxalates of some specific metals in plants, such as gadolinium or chromium, which cannot be fully extracted by the designated extractants, 2% acetic acid, or 0.6 M/L HCl. Therefore, SCE methods for the non-bivalent metal(loid)s have been emphasized in this work. Moreover, the application status, development trends, limitations, and future directions for SCE methods of plant metal(loid)s have been discussed. [ABSTRACT FROM AUTHOR]

The concentrations of six heavy metals were determined in the sediments of the Changli ecological monitoring area, northwest of the Bohai Bay. The spatial distribution of the metals was discussed, and the ecological risk was evaluated using the potential ecological risk index (PERI) and secondary phase enrichment factor (KSPEF). The content ranges of Cu, Pb, Cd, Cr, Ni, and Zn were 1.38–25.78, 11.13–21.96, 0.12–0.54, 15.44–120.60, 0.48–57.11, and 44.21–156.38 mg·kg−1, respectively. Based on the results of the geochemical speciation analysis, the residual phase was the main form for all five metals (Cu, Pb, Cd, Cr, and Zn). Compared to the assessment results of KSPEF, PERI is more suitable for the pollution evaluation of heavy metals. The results indicated that all the sediments pose a moderate to considerable level of risk, except site S14 (low risk), and Cd was found to be the main contributor of the ecological risk due to heavy metals. [ABSTRACT FROM AUTHOR]

Arsenic (As) levels in particulate matter (PM) are routinely monitored in cities of developed countries. Despite advances in the knowledge of its inorganic species in PM in urban areas, organic species are often overlooked with no information on their behaviour in urban parks – areas with increased potential for As biomethylation. Therefore, the aim of this study was to characterize As distribution, bioaccessibility, seasonal variation and speciation (AsIII, AsV, MMA, DMA and TMAO) in PM x –PM 10 of an urban park. Two sites with different distance from the road were selected for winter and summer sampling. From the PM samples, we gravimetrically determined PM 10 concentrations in the air and via ICP-MS the total As content there. To assess the portion of bioaccessible As, water extractable As content was analysed. Simultaneously, the As species in PM 10 water extracts were analysed via coupling of HPLC with ICP-MS method. There was no seasonal difference in PM 10 concentration in the park, probably due to the increased summer PM load related to recreational activities in the park and park design. Spatial distribution of total As in PM 10 and As fractional distribution in PM x suggested that As mostly didn't originate from traffic although highest As content was observed in the fine fraction (PM 2.5) related to combustion processes. However, significant winter increase of As (determined by AsIII and AsV) despite the unchanged concentration of PM 10 indicated a decisive influence of household heating-related combustion and possibly influence of reduced vegetation density. As present in the PM 10 was mostly in bioaccessible form. Seasonal influence of As biomethylation was clearly demonstrated on the TMAO specie during the summer campaign. Except the significant summer TMAO increase, the results also indicated the biomethylation influence on DMA. Therefore, an increased risk of exposure to organic As species in urban parks can be expected during summer. [Display omitted] • Park environment was chosen to evaluate the seasonal trend of organic As species. • The nature of the seasonal variations of As differs with its species. • Arsenic present in the PM 10 was mostly (86–100%) bioaccessible. • Approximately 82% of As was bounded to the PM x fractions of 0.15–1.6 μm. • TMAO controlled biomethylation-related summer increase in organic As species. [ABSTRACT FROM AUTHOR]

• Cu reduces mitochondrial H 2 O 2 emission induced by Cd or Zn. • Binary mixtures of Cu, Cd, and Zn reduce mitochondrial H 2 O 2 consumption. • Cu, Cd, and Zn singly and in binary mixtures inhibit thioredoxin reductase. • Cu singly and as a mixture with Cd or Zn stimulates glutathione peroxidase. • Binary mixtures of Cu, Cd, and Zn act additively or antagonistically. For continuous pumping of blood, the heart needs a constant supply of energy (ATP) that is primarily met via oxidative phosphorylation in the mitochondria of cardiomyocytes. However, sustained high rates of electron transport for energy conversion redox reactions predisposes the heart to the production of reactive oxygen species (ROS) and oxidative stress. Mitochondrial ROS are fundamental drivers of responses to environmental stressors including metals but knowledge of how combinations of metals alter mitochondrial ROS homeodynamics remains sparse. We explored the effects and interactions of binary mixtures of copper (Cu), cadmium (Cd), and zinc (Zn), metals that are common contaminants of aquatic systems, on ROS (hydrogen peroxide, H 2 O 2) homeodynamics in rainbow trout (Oncorhynchus mykiss) heart mitochondria. Isolated mitochondria were energized with glutamate-malate or succinate and exposed to a range of concentrations of the metals singly and in equimolar binary concentrations. Speciation analysis revealed that Cu was highly complexed by glutamate or Tris resulting in Cu2+ concentrations in the picomolar to nanomolar range. The concentration of Cd2+ was 7.2–7.5 % of the total while Zn2+ was 15 % and 21 % of the total during glutamate-malate and succinate oxidation, respectively. The concentration-effect relationships for Cu and Cd on mitochondrial H 2 O 2 emission depended on the substrate while those for Zn were similar during glutamate-malate and succinate oxidation. Cu + Zn and Cu + Cd mixtures exhibited antagonistic interactions wherein Cu reduced the effects of both Cd and Zn, suggesting that Cu can mitigate oxidative distress caused by Cd or Zn. Binary combinations of the metals acted additively to reduce the rate constant and increase the half-life of H 2 O 2 consumption while concomitantly suppressing thioredoxin reductase and stimulating glutathione peroxidase activities. Collectively, our study indicates that binary mixtures of Cu, Zn, and Cd act additively or antagonistically to modulate H 2 O 2 homeodynamics in heart mitochondria. [ABSTRACT FROM AUTHOR]