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Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the last years, there has been an increasing research interest in the analysis of biological fluids requiring non-invasive sampling for biomedical and clinical applications. In this work, we have focused on the nasal exudate with the aim of investigating the potential use of this fluid to know the role of iron in stroke and also for diagnosis. Potential differences in the nasal exudate, collected in swabs, from diagnosed hemorrhagic stroke, ischemic stroke, and control groups were investigated with regard to total iron by inductively coupled plasma-mass spectrometry, iron fractionation studies by size exclusion chromatography together with post-column isotope dilution analysis, and four proteins containing iron (ferritin, transferrin, lactoferrin, and ferroportin) with ELISA kits. All these analyses represent an analytical challenge, considering the rather limited amount of sample (10–40 mg) available, being the nasal exudate extracted from the swab with 300 µL 10 mM Tris/HCl, pH = 7.4. Studies to obtain reliable analytical information, such as the blank contribution of the sampling step, evaluation of the extraction efficiency of the nasal exudate from the swab, and normalization strategies for data treatment, have been carried out. Results showed that despite the limited number of investigated samples, fractionation studies as well as the concentrations of ferritin and ferroportin obtained with ELISA kits showed a differential behavior between the different cohorts. [ABSTRACT FROM AUTHOR]

[Objective] A method for the simultaneous determination of arsenate [As(Ⅲ)], Arsenate [As(Ⅴ)], monomethylarsenate (MMA), dimethylarsenate (DMA), Arsine betaine (AsB), methyl-selenocysteine (MeSeCys) and selenomide in food was developed by high performance liquid phase inductively coupled plasma mass spectrometry (HPLC-ICP-MS), and a total of 10 kinds of arsenic and selenium element forms of As and Se, including acid (SeMet), selenocysteine (SeCys2), selenite [Se(Ⅳ)] and selenate [Se(Ⅵ)] . [Methods] Taking selenium rich rice as the research object, the best extraction method was determined by comparing different extraction methods and different kinds of enzymes. Moreover, different chromatographic columns, mobile phase composition, mobile phase pH, mobile phase flow, mobile phase methanol content and column temperature were compared to determine the best extraction and separation conditions. [Results] The optimal separation conditions were using Aglient ZORBAX SB-Aq chromatographic column with 20 mmol/L citric acid + 5 mmol/L sodium hexane sulfonate + 4% methanol as the mobile phase gradient with pH values of 4.0 and 6.0 respectively. Elution was performed at a flow rate of 1.0 mL/min, and inductively coupled plasma mass spectrometry (ICP-MS) was detected using HEHe mode. The optimal extraction condition is Tris-HCl (pH 7.5) buffer solution adding 15 mg proteinase K and 15 mg proteinase E. This method can completely separate 10 different forms of arsenic and selenium within 5 minutes. In the range of 0～50 μg/L, the linear relationship between the forms of each element is good, and the correlation coefficient R>0.999 5. The detection limits of As(Ⅴ), MMA, As(Ⅲ), DMA, AsB, Se(Ⅵ), Se(Ⅳ), SeCys2, MeSeCys and SeMet are 0.10, 0.10, 0.12, 0.14, 0.22, 0.15, 0.15, 0.18, 0.12, 0.15 μg/L respectively. The spiked recovery rate ranged from 76.0% to 104.2%, and the relative standard deviation ranged from 1.1% to 8.5%. [Conclusion] This method is simple, fast, highly sensitive and fully meets the requirements for accurate quantitative analysis of arsenic and selenium speciation in selenium-rich foods.

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]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Medicine Food Homology (MFH) has been applied for both food and medicine. However, the possible and adverse risks of MFH are associated with the arsenic element, leading to various health disorders, including hypertension, neurological disease, respiratory tract disease, cardiovascular disease, and even the lethal. Therefore, it is significantly important to determine the arsenic concentration of MFH plants for more accurate toxicological assessments. The present study aimed to investigate the content of total arsenic (t-As) and inorganic arsenic (AsIII and AsV). 54 kinds of MFH were collected from different provinces in China, namely Chinese prickly ash, tangerine peel, cinnamon, goji berry, mulberry, hawthorn berry, coix seed, lotus seed, licorice, Astragali radix, Platycodonis radix, clove, honeysuckle, chrysanthemum, rose, lily, mulberry leaf and Perilla frutescent, according to inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). In addition, the arsenic speciation analysis was also made to consider the precision, limit of detection (LOD), and limit of quantification (LOQ). The results show that: (1) The arsenic concentration of MFH varied greatly in the geographical origin, cultivars, and arsenic species. (2) The LOD/LOQ values of t-As, AsIII and AsV were 0.003/0.010, 0.004/0.012 and 0.004/0.012, respectively. The recovery rates of tAs and inorganic arsenic were 85.3%-88.0% and 94.90%-97.00%, respectively. (3) The concentration of t-As for the 54 kinds of MFH plants ranged from 0.005 to 1.627 mg/kg, which under the limited value (2 mg/kg), according to the regulation of Chinese Pharmacopoeia. Exceptionally, Chinese prickly ash (with the highest value) from Sichuan (3.407 mg/kg) was attributed to their contaminated sources. Specifically, the t-As of root MFH plants (0.039-0.370 mg/kg) significantly higher than that of seed (below LOD-0.081) (P<0.05). Most of the arsenic that is taken up during growth accumulated in roots and iron plaque around the roots via three main ways of symplast, apoplast, and plant vascular. Moreover, the highest t-As was observed among four types of flower samples (0.039-0.427 mg/kg), namely clove, honeysuckle, rose, and chrysanthemum, honeysuckle from Shanxi Province. While the minimum was found in the rose sample from Gansu province. Furthermore, the t-As of lily (0.019-0.035 mg/kg) was significantly lower than that of mulberry leaf (0.388-0.496 mg/kg) and Perilla frutescent (0.275-1.627 mg/kg) (P<0.05) in the leaf MFH plants. (4) Significant differences were found in the inorganic arsenic from all MFH plants (P<0.05). The concentration range of AsIII (

Environmental context: Seaweeds are known to accumulate high levels of arsenic, and cellular concentrations may reach several orders of magnitude higher than that of the surrounding environment. Arsenic may be methylated by seaweed cells and further metabolised to water-soluble arsenic-containing sugars through unknown pathways. Whether these compounds are the result of a detoxification process or are produced with a biological purpose remains to be seen. Rationale: Seaweeds are known to accumulate high levels of arsenic, which may be subsequently metabolised to small, methylated compounds or become incorporated into large biological molecules such as arsenosugars. The mechanism of arsenosugars production in macroalgae is still largely unknown. Method: This study reports the arsenic speciation of 13 brown, red and green macroalgae collected in May 2021 and February 2022. Water-soluble arsenic speciation was measured using high-performance liquid chromatography–inductively coupled plasma–mass spectrometry (HPLC-ICP-MS) after extraction with a 3% (v/v) hydrogen peroxide solution. Results: Arsenosugars were found to account for the majority of the extracted arsenic in all seaweed samples (>50%), with only small amounts of dimethylarsinate and monomethylarsonate present. Levels of toxic iAs were also low (−1). Sulfur-containing arsenosugars were the dominant arsenicals in brown macroalgae, whereas the phosphate ribose was most abundant in red and green. Discussion: The majority of seaweed species appear to have the ability to synthesise all four arsenosugar derivatives; however, it is unclear why some are produced in higher abundances. The production of arsenosugars may be an efficient way of excluding arsenic from the cytosol, or may serve as useful components in the cell wall matrix, as extremely high levels can be tolerated by the seaweed with no ill effects. AsSug-gly and AsSug-PO4 were detected in every sample analysed, which might suggest that AsSug-gly is the starting point for AsSug-PO4, which could be formed by AsSug-gly binding to phosphate-containing lipids in the cell membrane. Further studies should use both imaging and speciation techniques to investigate the formation of arsenosugars. Environmental context. Seaweeds are known to accumulate high levels of arsenic, and cellular concentrations may reach several orders of magnitude higher than that of the surrounding environment. Arsenic may be methylated by seaweed cells and further metabolised to water-soluble arsenic-containing sugars through unknown pathways. Whether these compounds are the result of a detoxification process or are produced with a biological purpose remains to be seen. (Image credit: Rebecca Sim.) [ABSTRACT FROM AUTHOR]

Seaweed is becoming increasingly popular in the Western diet as consumers opt for more sustainable food sources. However, seaweed is known to accumulate high levels of arsenic—which may be in the form of carcinogenic inorganic arsenic (iAs). Here we propose a fast method for the routine measurement of iAs in seaweed using HPLC-ICP-MS without coelution of arsenosugars that may complicate quantification. The developed method was optimised using design of experiments (DOE) and tested on a range of reference materials including TORT-3 (0.36 ± 0.03 mg kg−1), DORM-5 (0.02 ± 0.003 mg kg−1), and DOLT-5 (0.07 ± 0.007 mg kg−1). The use of nitric acid in the extraction solution allowed for the successful removal of interferences from arsenosugars by causing degradation to an unretained arsenosugar species, and a recovery of 99 ± 9% was obtained for iAs in Hijiki 7405-b when compared with the certified value. The method was found to be suitable for high-throughput analysis of iAs in a range of food and feed matrices including Asparagopsis taxiformis seaweed, grass silage, and insect proteins, and offers a cost-effective, fast, and robust option for routine analysis that requires minimal sample preparation. The method may be limited with regards to the quantification of dimethylarsenate (DMA) in seaweed, as the acidic extraction may lead to overestimation of this analyte by causing degradation of lipid species that are typically more abundant in seaweed than other marine matrices (i.e. arsenophospholipids). However, the concentrations of DMA quantified using this method may provide a better estimation with regard to exposure after ingestion and subsequent digestion of seaweed. [ABSTRACT FROM AUTHOR]

Rice is a staple food and known to accumulate inorganic arsenic (iAs), which is a class 1 carcinogen to humans. Arsenic field-deployable method kits, designed for water testing, are able to screen iAs in rice, to assure food safety and quick decision-making without the need for laboratory analysis. For the arsenic extraction within the field method, nitric acid is used. To make the field method on-site safer, cost-effective and easier to handle, the method was adapted using a Cola in the extraction process. The adapted field-deployable method was tested by screening a total of 30 rice and rice products from the Austrian market. To verify the results obtained by the Cola extraction field-deployable method, the obtained iAs concentration was compared to HPLC-ICP-MS results. The Cola extraction field method obtained an LOD of 39 µg iAs kg−1 rice, and with an average reproducibility of 14% RSD, the method was capable of recording no false-negative but 7% false-positive values at the 2023 updated European Commission (EC) limits for rice. All, but one, screened rice samples were within the EU limits for iAs in rice and rice products. [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]

This study presents a new technique for determining vitamin B12 in milk powder using high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). We used ultrasonics with potassium ferrocyanide and zinc acetate solutions to extract the samples. 59Co was employed as the analytical target for cyanocobalamin. It was separated using a Phenomenex Luna 5 μm C18 (250 × 4.6 mm) chromatographic column with a mobile phase consisting of 1.6 mmol/L EDTA and 0.4 mmol/L KH2PO4 in a 60% v/v methanol solution (pH = 4.0). The sample has an excellent separating degree for free cobalt and cyanocobalamin, and isocratic elution can be finished within 4.0 min. To eliminate the matrix interference due to the presence of milk powder, we applied collision mode (KED). The linear range of cyanocobalamine ranged from 1.0 μg/L to 20 μg/L, with correlation coefficients (r2) of 0.9994. The limit of detection (LOD) was 0.63 μg/kg, and the limit of quantitation (LOQ) was 2.11 μg/kg. The mean recoveries were in the range of 87.4–103.6%. The accuracy and precision of the developed method are well suited for the fast quantification of the trace vitamin B12 in milk powder. [ABSTRACT FROM AUTHOR]

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Selenium-enriched yeast possesses the unique ability of transforming chemical selenium, such as sodium selenite, into a biologically active form, which mitigates its toxic effects on the human body. The transformation product of this process, selenomethionine, can be safely and effectively absorbed and utilized by the human body; hence, it has been spiked into a selenium-enriched supplement. This study employs two distinct measurement strategies to determine the selenomethionine content in two candidate reference materials, a selenium-enriched yeast powder and supplement, using both organic and inorganic mass spectrometry. The concentrations of selenomethionine in the selenium-enriched yeast were determined using HPLC-ICP-MS and HPLC- ESI-MS/MS, with mass fractions measured at 718 mg SeMet kg−1 and 715 mg SeMet kg−1, respectively. Notably, both methods yielded consistent results for the selenium supplement, with a selenomethionine mass fraction of 59 mg SeMet kg−1. Ultimately, the certified values of these candidate reference materials were determined as 716 mg kg−1 and 59 mg SeMet kg−1 with expanded uncertainties of 36 mg SeMet kg−1 (k = 2) and 5 mg SeMet kg−1 (k = 2), respectively. The development of these candidate reference materials serves as a valuable reference for diverse methods aiming to determine the value of organic selenium speciation in complex food substrates. [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]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An approach to the highly sensitive and selective determination of the bromine-containing antiviral drug umifenovir (Arbidol) and its metabolites in natural and waste water, activated sludge, and bottom sediments by chromatography-mass spectrometry based on a combination of two techniques– inductively coupled plasma mass spectrometry (ICP MS) and electrospray ionization high-resolution mass spectrometry (ESI HRMS) is developed. Reversed-phase chromatographic separation and detection based on ESI HRMS provide the reliable detection and identification of analytes in complex matrices, while the use of ICP-MS with 79Br signal detection makes it possible to exclude matrix effects and use a single analytical standard for quantitative analysis. The use of solid-phase extraction and pressurized liquid extraction as sample preparation methods made it possible to achieve limits of detection at a level of 0.2 ng/L and 2 µg/kg for liquid and solid samples, respectively. The developed approach was successfully tested in the analysis of real samples. It is shown that the concentrations of analytes in urban wastewaters are in the range 4.4–260 ng/L. The highest concentration (up to 3.7 mg/kg) is characteristic of activated sludge, which acts as an effective sorbent for umifenovir and its transformation products. [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.

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).

This study presents a new technique for determining vitamin B12 in milk powder using high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). We used ultrasonics with potassium ferrocyanide and zinc acetate solutions to extract the samples. 59Co was employed as the analytical target for cyanocobalamin. It was separated using a Phenomenex Luna 5 μm C18 (250 × 4.6 mm) chromatographic column with a mobile phase consisting of 1.6 mmol/L EDTA and 0.4 mmol/L KH2PO4 in a 60% v/v methanol solution (pH = 4.0). The sample has an excellent separating degree for free cobalt and cyanocobalamin, and isocratic elution can be finished within 4.0 min. To eliminate the matrix interference due to the presence of milk powder, we applied collision mode (KED). The linear range of cyanocobalamine ranged from 1.0 μg/L to 20 μg/L, with correlation coefficients (r2) of 0.9994. The limit of detection (LOD) was 0.63 μg/kg, and the limit of quantitation (LOQ) was 2.11 μg/kg. The mean recoveries were in the range of 87.4–103.6%. The accuracy and precision of the developed method are well suited for the fast quantification of the trace vitamin B12 in milk powder.

Summary: Quantification of some important elements, including several heavy metals, and assessment of health risks associated with rice consumption was conducted. Twelve different rice varieties were analysed for fourteen metals i.e. As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, Sr, U, and Zn using Inductively Coupled Plasma–Mass Spectrometry (ICP‐MS). In addition, arsenic species were separated and determined by High‐Performance Liquid Chromatography coupled with ICP‐MS. The As levels ranged from 24.16 to 178.66 μg kg−1, while Cd levels varied from 31.38 to 155.88 μg kg−1. The principal component analysis clearly differentiates traditional and non‐traditional varieties. The maximum Estimated Daily Intake (EDI) value, 120.56 μg kg−1 bw day−1, was reported for Zn from Kekulu Samba, while the highest Cancer Risk (CR) value, 1.17 × 10−02, was reported for Cd from red raw rice. The Madathawalu rice recorded the highest Target Hazard Quotient (THQ) value of 5.51. The EDI, CR, and THQ levels showed some health risks for some rice varieties. The most predominant species detected was As(III), followed by As(V), and the total inorganic As level ranged from 77.3 to 91.3%. THQ and CR levels suggested considerable potential non‐carcinogenic risk and carcinogenic risk due to the consumption of rice. [ABSTRACT FROM AUTHOR]

Rice can accumulate more organic and inorganic arsenic (iAs) than other crop plants. In this study, the localization of As in rice grains was investigated using High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry (HPLC-ICP-MS) based on 26 rice varieties collected from two provinces. In all the samples, the total As contents in polished rice were 0.03–0.37 mg/kg, with average values of 0.28 and 0.21 mg/kg for two sample sets. The results of the determination of arsenic speciation in different components of rice grain showed that in the polished and brown rice the mean value of arsenite (As(III)) was nearly twice than that of arsenate (As(V)). The regional difference was observed in both total As contents and As speciation. The reason may be that As(III) is more mobile than As(V) in a dissociated form and because of soil properties, rice varieties, and the growing environment. The proportion of iAs and the total As in rice bran was higher than that in polished rice, and this is because As tends accumulate between the husk and the endosperm. In our study, selenium could alleviate the risk of arsenic toxicity at the primary stage of rice growth. Co-exposure to As and Se in germinated rice indicated that the reduction in As accumulation in polished rice reached 73.8%, 76.8%, and 78.3% for total As, As(III), and As(V) when compared with rice treated with As alone. The addition of Se (0.3 mg/kg) along with As significantly reduced the As amount in different parts of germinated rice. Our results indicated that Se biofortification could alleviate the As accumulation and toxicity in rice crops. [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]

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Arsenic (As) and Cadmium (Cd) are toxic to rice plants. However, selenium (Se) has the potential to regulate As and Cd toxicity. The present study aimed to evaluate the co-exposure to As5+ and Se6+ species in two rice cultivars, BRS Pampa and EPAGRI 108. The plants were divided into six groups and cultivated until complete maturation of the grains, under greenhouse conditions. Regarding total As and inorganic As (i-As) accumulation in grains, the highest concentrations were found for BRS Pampa. For Se, EPAGRI 108 presented the highest concentration of inorganic and organic Se (i-Se and o-Se). The exposure assessments showed that Se biofortification can mitigate the As accumulation in rice and, consequently, the risk of As and Cd toxicity in grains for human consumption. The combined effect of As and Se in rice plants could represent an alternative to biofortify this food in a safe way and with a higher percentage of bioavailable Se. Although Se is able to mitigate As toxicity in rice plants, in the present study we showed that co-exposure in different cultivars under the same growing conditions may present different responses to As and Se exposure. [ABSTRACT FROM AUTHOR]

Selenium-enriched yeast possesses the unique ability of transforming chemical selenium, such as sodium selenite, into a biologically active form, which mitigates its toxic effects on the human body. The transformation product of this process, selenomethionine, can be safely and effectively absorbed and utilized by the human body; hence, it has been spiked into a selenium-enriched supplement. This study employs two distinct measurement strategies to determine the selenomethionine content in two candidate reference materials, a selenium-enriched yeast powder and supplement, using both organic and inorganic mass spectrometry. The concentrations of selenomethionine in the selenium-enriched yeast were determined using HPLC-ICP-MS and HPLC- ESI-MS/MS, with mass fractions measured at 718 mg SeMet kg−1 and 715 mg SeMet kg−1, respectively. Notably, both methods yielded consistent results for the selenium supplement, with a selenomethionine mass fraction of 59 mg SeMet kg−1. Ultimately, the certified values of these candidate reference materials were determined as 716 mg kg−1 and 59 mg SeMet kg−1 with expanded uncertainties of 36 mg SeMet kg−1 (k = 2) and 5 mg SeMet kg−1 (k = 2), respectively. The development of these candidate reference materials serves as a valuable reference for diverse methods aiming to determine the value of organic selenium speciation in complex food substrates.

A simple, rapid and robust method for routine speciation analysis of methylmercury (MeHg) by reversed phase high-performance liquid chromatography coupled to inductively coupled plasma-mass spectrometry (RP HPLC-ICP-MS) following closed microwave-assisted extraction was optimised and validated using the accuracy profile approach. An effective separation of MeHg from its inorganic Hg precursor (Hg2+) was achieved in less than 3 min using RP HPLC by means of a peptide mapping column. A robust method validation was carried out using the accuracy profile approach by carrying out seven measurement series in duplicate on (seven) different days over a timespan of 2 months by two different operators. The measurement bias corresponding to the validity domain ranged from −0.2% to 2%, whereas the coefficient of variation in terms of repeatability (CVr) varied from 1.5% to 8.3% (depending on the analyte level) while the coefficient of variation in terms of intermediate reproducibility (CVR) ranged from 3.6% to 8.3%. The limit of quantification was 0.0032 mg kg−1 (wet weight). This novel approach was proved to be highly robust and suitable for the routine determination of MeHg in fishery products with satisfactory analytical performances in order to accurately assess the risks related to MeHg due to the consumption of this type of foodstuffs. [ABSTRACT FROM AUTHOR]

[Display omitted] • HBV Se > 0 were obtained for raw materials and processed fish-derived products. • SeMet and SeMeSeCys were identified in all raw materials and final products. • Elaboration processes of products might not affect the integrity of the Se species. • Hg, Se and Se species bioaccessibilities were assessed using an in vitro model. • Caco-2 cell viability did not decreased after exposure to bioaccesible fraction. Processing conditions applied during food production could affect food component contents and bioaccessibility. Here, possible changes in Hg and Se total and species contents and bioaccessibility have been tracked in each stage of the production chain of processed fish-derived products. Therefore, Se:Hg molar ratio and Selenium Health Benefit Value (HBV Se) were calculated for final products and raw materials, resulting favorable in all cases, suggesting the safety of surimi-based products regarding mercury. Speciation studies revealed the presence of SeMeSeCys and SeMet in all samples. Thus, the integrity of the selenium species seems to be maintained. Moreover, in vitro gastrointestinal digestion model evidenced that Se bioaccessibility ranged between 20–39 % for all samples, while in case of Hg was between 8–37 %. Additionaly, SeMeSeCys and SeMet were also identified in the gastrointestinal extracts. Finally, no cytotoxicity was observed after exposure of Caco-2 cells to the gastrointestinal extracts. [ABSTRACT FROM AUTHOR]

Arsenic (As) accumulated in genuine medicinal materials will not only deteriorate the original medicinal properties of the medicinal materials but also harm the eater’s body. In this study, inductively coupled plasma mass spectrometry (ICP-MS) technology was used to investigate the total As content of honeysuckle in four regions, namely Fengqiu, Henan, Xinmi, Shandong, and Julu, Hebei, as well as the speciation and content of As in the roots, stems, and leaves of honeysuckle. This research shows that the total As content of honeysuckle in the four regions was 0.25–0.3 mg/kg. At 1.5 mol/L H3PO4, 200 W, we performed ultrasonic extraction for 30 min at 60°C and adopted high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) to analyze the As speciation of honeysuckle plants. The soil As speciation mainly exists in the form of As(v). In the medicinal part of honeysuckle, the amount of different As speciation is ranked in the descending order as As(v) > As(iii) > dimethyl As acid > monomethyl As acid > AsC. As(v) is the main speciation, accounting for 64.5% of the total, followed by the most toxic As(iii), which is 18.8%. As(v) absorbed by the root system of honeysuckle from the soil tends to transform to As(iii) when transported upwards, and the transformation process mainly occurs in the roots.

Mercury (Hg) and its compounds are highly toxic for humans and ecosystems, and their chemical forms determine both their behavior and transportation as well as their potential toxicity for human beings. Determining the various species of an element is therefore more crucial than understanding its overall concentration in samples. For this reason, several studies focus on the development of new analytical techniques for the identification, characterization, and quantification of Hg compounds. Commercially available, hyphenated technology, such as HPLC-ICP-MS, supports the rapid growth of speciation analysis. This review aims to summarize and critically examine different approaches for the quantification of mercury species in different samples using HPLC-ICP-MS. The steps preceding the quantification of the analyte, namely sampling and pretreatment, will also be addressed. The scenarios evaluated comprehend single and multi-element speciation analysis to create a complete guide about mercury content quantification.

The biofortification of cereals is a potential solution for increasing Se levels in the human diet. Here we evaluated whether applying selenate and organic N and S sources via foliar alters Se content and species in durum wheat grain. Field trials were conducted in a Mediterranean environment in 2017–2018 and 2018–2019 on old (Cappelli and old Saragolla) and modern (Marco Aurelio and Nadif) durum wheat varieties. Four organic fertilization strategies were evaluated: the control (dry blood meal at sowing), the application of foliar S (Bio-sulphur at flag leaf) and N (liquid blood meal at the beginning of heading), and their combined use in interaction with a foliar application of selenate at the booting stage. The Se content in grain was determined using ICP-MS and its speciation throughout HPLC-ICP-MS and HPLC-ESI-MS/MS. In 2018, the lower rainfall in the ten days before the Se foliar application caused a higher Se accumulation in the grain (1.63 vs. 1.44 mg kg−1 in 2017–2018 and 2018–2019, respectively). A negative effect of organic foliar S on Se content in grain was observed (−24% with respect to the control). The modern Nadif showed the highest Se content (1.87 mg kg−1), followed by the old variety Cappelli (1.57 mg kg−1). Finally, the Se speciation analysis showed the presence of SeMet and SeMetSeCys. The organic fertilization affected only SeMet, with lower values under organic S fertilization and higher values under organic N fertilization. [ABSTRACT FROM AUTHOR]

Mushrooms have unique properties in arsenic metabolism. In many commercial and wild-grown mushrooms, arsenobetaine (AsB), a non-toxic arsenical, was found as the dominant arsenic species. The AsB biosynthesis remains unknown, so we designed experiments to study conditions for AsB formation in the white button mushroom, Agaricus bisporus. The mushrooms were treated with various arsenic species including arsenite (As(III)), arsenate (As(V)), methylarsenate (MAs(V)), dimethylarsenate (DMAs(V)) and trimethylarsine oxide (TMAsO), and their accumulation and metabolism were determined using inductively coupled mass spectrometer (ICP-MS) and high-pressure liquid chromatography coupled with ICP-MS (HPLC-ICP-MS), respectively. Our results showed that mycelia have a higher accumulation for inorganic arsenicals while fruiting bodies showed higher accumulation for methylated arsenic species. Two major arsenic metabolites were produced in fruiting bodies: DMAs(V) and AsB. Among tested arsenicals, only MAs(V) was methylated to DMAs(V). Surprisingly, AsB was only detected as the major arsenic product when TMAsO was supplied. Additionally, AsB was only detected in the fruiting body, but not mycelium, suggesting that methylated products were transported to the fruiting body for arsenobetaine formation. Overall, our results support that methylation and AsB formation are two connected pathways where trimethylated arsenic is the optimal precursor for AsB formation. [ABSTRACT FROM AUTHOR]

Background: Selenoneine, the selenium analogue of the sulfur antioxidant ergothioneine, has been ascribed a multitude of beneficial health effects. Natural nutritional sources for this selenium species are, hence, of high interest. So far marine fish is the only significant selenoneine source consumed by larger parts of the population worldwide., Methods: As selenoneine and ergothioneine share their biosynthetic pathways and transport mechanisms and the popular edible porcini mushroom Boletus edulis is rich in ergothioneine and selenium, we conducted a preliminary study investigating a composite sample of two specimens of B. edulis for their selenoneine content by HPLC coupled to elemental and molecular mass spectrometry after aqueous extraction., Results: Selenium speciation analysis by HPLC-ICPMS revealed that ca. 860 µg Se kg -1 wet mass (81 % of the total Se) co-eluted with a selenoneine standard and a minor selenium species with Se-methylselenoneine. The presence of selenoneine was rigorously proven by HPLC-ESI-Orbitrap MS. The selenoneine content of the investigated specimens of B. edulis was higher than that of commonly consumed muscle of marine fish species, like tuna or mackerel., Conclusion: This is the first report of a terrestrial food source containing significant selenoneine levels. Our results suggest that B. edulis might represent a complementary natural supply with this health-relevant selenium species for humans., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Doris Kuehnelt reports financial support was provided by Austrian Science Fund. If there are other authors, they 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 © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Rice can accumulate more organic and inorganic arsenic (iAs) than other crop plants. In this study, the localization of As in rice grains was investigated using High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry (HPLC-ICP-MS) based on 26 rice varieties collected from two provinces. In all the samples, the total As contents in polished rice were 0.03–0.37 mg/kg, with average values of 0.28 and 0.21 mg/kg for two sample sets. The results of the determination of arsenic speciation in different components of rice grain showed that in the polished and brown rice the mean value of arsenite (As(III)) was nearly twice than that of arsenate (As(V)). The regional difference was observed in both total As contents and As speciation. The reason may be that As(III) is more mobile than As(V) in a dissociated form and because of soil properties, rice varieties, and the growing environment. The proportion of iAs and the total As in rice bran was higher than that in polished rice, and this is because As tends accumulate between the husk and the endosperm. In our study, selenium could alleviate the risk of arsenic toxicity at the primary stage of rice growth. Co-exposure to As and Se in germinated rice indicated that the reduction in As accumulation in polished rice reached 73.8%, 76.8%, and 78.3% for total As, As(III), and As(V) when compared with rice treated with As alone. The addition of Se (0.3 mg/kg) along with As significantly reduced the As amount in different parts of germinated rice. Our results indicated that Se biofortification could alleviate the As accumulation and toxicity in rice crops.

A systematic investigation on the cellular uptake, intracellular dissolution, and in vitro biological effects of ultra-small (<10 nm) iron hydroxide adipate/tartrate coated nanoparticles (FeAT-NPs) was carried out in intestinal Caco-2, hepatic HepG2 and ovarian A2780 cells, and the nucleotide excision repair (NER) deficient GM04312 fibroblasts. Quantitative evaluation of the nanoparticles uptake, as well as their transformation within the cell cytosol, was performed by inductively coupled plasma mass spectrometry (ICP-MS), alone or in combination with high performance liquid chromatography (HPLC). The obtained results revealed that FeAT-NPs are effectively taken up in a cell type-dependent manner with a minimum dissolution after 3 h. These results correlated with no effects on cell proliferation and minor effects on cell viability and reactive oxygen species (ROS) production for all the cell lines under study. Moreover, the comet assay results revealed significant DNA damage only in GM04312 cells. In vivo genotoxicity was further studied in larvae from Drosophila melanogaster, using the eye-SMART test. The obtained results showed that FeAT-NPs were genotoxic only with the two highest tested concentrations (2 and 5 mmol·L−1 of Fe) in surface treatments. These data altogether show that these nanoparticles represent a safe alternative for anemia management, with high uptake level and controlled iron release. [ABSTRACT FROM AUTHOR]

BACKGROUND As a highly sensitive analytical technique, ICP-MS has been widely used in the analysis of trace inorganic elements. Combined with chromatographic separation technology, it provides a powerful detection tool for elemental speciation analysis. OBJECTIVES To summarize the research progress of elemental speciation analysis by inductively coupled plasma mass spectrometry hyphenated techniques. METHODS The main methods of elemental speciation analysis by ICP-MS hyphenated techniques were summarized and compared. The methods included: (1) Gas chromatography coupled with ICP-MS (GC-ICP-MS). (2) Capillary electrophoresis coupled with ICP-MS (CE-ICP-MS). (3) Ion chromatography coupled with ICP-MS (IC-ICP-MS). (4) High performance liquid chromatography coupled with ICP-MS (HPLC-ICP-MS). The main application fields of elemental speciation analysis in China were biomedical field, food and drug safety monitoring and ecoenvironmental geochemistry. RESULTS GC-ICP-MS has high sensitivity and is suitable for volatile samples, its application is thus limited. CE-ICP-MS has fast analysis and high separation efficiency, but the limitation of sample injection volume makes the method detection limitation high. IC-ICP-MS mainly analyzes anions, cations and small molecular polar compounds. It is a useful complement to HPLC, but the mobile phase containing inorganic salts may block the sampling cone. HPLC-ICP-MS has been the most widely used technology in speciation analysis because of its wide application fields and simple technology. CONCLUSIONS Sample preparation research for complex matrices, preparing standard materials, and developing simultaneous multi-element speciation analysis methods are the research direction of elemental speciation analysis.

• Simultaneous quantification of tin and lead species was achieved by HPLC-ICP-MS. • Aqueous mobile phase afforded 16 min separation of eight species. • LODs (0.02–0.24 μg L−1) were obtained for marine food. • Tin and lead species were detected down to 5 μg kg–1 in Antarctic krill and fish. • The method is sensitive, efficient and environment-friendly for routine analysis. Tin and lead are a global concern considering their species-dependent toxicity, bioavailability and transformation. Simultaneous speciation analysis of tin and lead is challenging for a large food capacity containing unstable species. Herein, we developed two sensitive methods for rapid quantification of tin and lead species in Antarctic seafood by high-performance liquid chromatography and inductively coupled plasma mass spectrometry based on strong cation-exchange and Amphion columns. Inorganic tin and lead, four organotin and two organolead compounds can be analysed in 16 min on a 10-cm Amphion II column (mobile phase: 4 mM sodium dodecyl benzene sulfonate at pH 2.0) with 0.02–0.24 μg L–1 detection limits. The method was applied to Antarctic krill and fish, demonstrating the presence of any tin and lead species down to μg kg−1 level. Overall, the proposed methods are sensitive, efficient and environment-friendly for routine speciation analysis of tin and lead in food samples. [ABSTRACT FROM AUTHOR]

Arsenic (As) and Cadmium (Cd) are toxic to rice plants. However, selenium (Se) has the potential to regulate As and Cd toxicity. The present study aimed to evaluate the co-exposure to As5+ and Se6+ species in two rice cultivars, BRS Pampa and EPAGRI 108. The plants were divided into six groups and cultivated until complete maturation of the grains, under greenhouse conditions. Regarding total As and inorganic As (i-As) accumulation in grains, the highest concentrations were found for BRS Pampa. For Se, EPAGRI 108 presented the highest concentration of inorganic and organic Se (i-Se and o-Se). The exposure assessments showed that Se biofortification can mitigate the As accumulation in rice and, consequently, the risk of As and Cd toxicity in grains for human consumption. The combined effect of As and Se in rice plants could represent an alternative to biofortify this food in a safe way and with a higher percentage of bioavailable Se. Although Se is able to mitigate As toxicity in rice plants, in the present study we showed that co-exposure in different cultivars under the same growing conditions may present different responses to As and Se exposure.

It is well established that arsenic (As) has many toxic compounds, and in particular, inorganic As (iAs) has been classified as a type-1 carcinogen. The measuring of As species in rice flour is of great importance since rice is a staple of the diet in many countries and a major contributor to As intake in the Asian diet. In this study, several solvents and techniques for the extraction of As species from rice flour samples prior to their analysis by HPLC-ICP-MS were investigated. The extraction methods were examined for their efficiency in extracting various arsenicals from a rice flour certified reference material, NMIJ-7532a, produced by the National Metrology Institute of Japan. Results show that ultrasound-assisted extraction at 60 °C for 1 h and then heating at 100 °C for 2.5 h in the oven using a thermostable α-amylase aqueous solution was highly effective in liberating the arsenic species. The recoveries of iAs and dimethylarsinic acid (DMA) in NMIJ-7532a were 99.7% ± 1.6% (n = 3) and 98.1% ± 2.3% (n = 3), respectively, in comparison with the certificated values. Thus, the proposed extraction method is a green procedure that does not use any acidic, basic, or organic solvents. Moreover, this extraction method could effectively maintain the integrity of the native arsenic species of As(III), As(V), monomethylarsonate (MMA), DMA, arsenobetaine (AsB) and arsenocholine (AsC). Under the optimum extraction, chromatography and ICP-MS conditions, the limits of detection (LOD) obtained were 0.47 ng g−1, 1.67 ng g−1 and 0.80 ng g−1 for As(III), As(V) and DMA, respectively, while the limits of quantification (LOQ) achieved were 1.51 ng g−1, 5.34 ng g−1 and 2.57 ng g−1 for As(III), As(V) and DMA, respectively. Subsequently, the proposed method was successfully applied to As speciation analysis for several rice flour samples collected from contaminated areas in China. [ABSTRACT FROM AUTHOR]

A simple and efficient dithizone-functionalized solid-phase extraction (SPE) procedure, online coupled with high-performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry, was developed for the first time for enrichment and determination of ultra-trace mercury (Hg) species (inorganic divalent Hg (Hg(II)), methylmercury (CH 3 Hg(II)) and ethylmercury (C 2 H 5 Hg(II)) in cereals and environmental samples. In the proposed method, functionalization of the commercial C 18 column with dithizone, enrichment, and elution of the above Hg species can be completed online with the developed SPE device. A simple solution of 2-mercaptoethanol (1% (V/V)) could be used as an eluent for both the SPE and HPLC separation of Hg species, significantly simplifying the method and instrumentation. The online SPE method was optimized by varying dithizone dose, 2-mercaptoethanol concentration, and sample volume. In addition, the effect of pH, coexisting interfering ions, and salt effect on the enrichment was also discussed. Under the optimized conditions, the detection limits of Hg species for 5 mL water sample were 0.15 ng/L for Hg(II), 0.07 ng/L for CH 3 Hg(II), and 0.04 ng/L for C 2 H 5 Hg(II) with recoveries in the range of 85%–100%. The developed dithizone-functionalized C 18 SPE column can be reused after a single functionalization, which significantly simplifies the enrichment step. Moreover, the stability of Hg species enriched on the SPE column demonstrated its suitability for field sampling of Hg species for later laboratory analysis. This environment-friendly method offers a robust tool to detect ultra-trace Hg species in cereals and environmental samples. [Display omitted] [ABSTRACT FROM AUTHOR]

Arsenic in environmental health has caused public concerns all over the world. However, high levels of arsenic residues in medicinal animals have not received enough attention. Medicinal earthworms are consumed widely in China, but its arsenic potential health risks to humans are unknown. This work investigated the total concentration, bioaccessibility, and speciation of arsenic in earthworms by ICP-MS and HPLC-ICP-MS to evaluate its potential health risks to humans. Arsenic was found in all earthworms at concentrations ranging from 0.4 to 53.6 mg kg−1. The bioaccessibility of arsenic (bAs) varied significantly and ranged from 12.1 to 69.1%, with inorganic arsenic (iAs, including As(III) and As(V)) as the predominant species. Furthermore, a small amount of arsenobetaine (AB) was found. The estimated daily intake dose (EDI), hazard quotient (HQ), and carcinogenic risk (CR) of arsenic in most of the samples exceeded the safe threshold level. Results from this study indicated that the potential health risks by the consumption of earthworms may not be negligible. Herein, recommendations for the use of earthworms and regulatory recommendations for arsenic limit standards were proposed. This study reminds us that more control and monitoring of arsenic in medicinal animals should be carried out. [ABSTRACT FROM AUTHOR]

Arsenic in environmental health has caused public concerns all over the world. However, high levels of arsenic residues in medicinal animals have not received enough attention. Medicinal earthworms are consumed widely in China, but its arsenic potential health risks to humans are unknown. This work investigated the total concentration, bioaccessibility, and speciation of arsenic in earthworms by ICP-MS and HPLC-ICP-MS to evaluate its potential health risks to humans. Arsenic was found in all earthworms at concentrations ranging from 0.4 to 53.6 mg kg−1. The bioaccessibility of arsenic (bAs) varied significantly and ranged from 12.1 to 69.1%, with inorganic arsenic (iAs, including As(III) and As(V)) as the predominant species. Furthermore, a small amount of arsenobetaine (AB) was found. The estimated daily intake dose (EDI), hazard quotient (HQ), and carcinogenic risk (CR) of arsenic in most of the samples exceeded the safe threshold level. Results from this study indicated that the potential health risks by the consumption of earthworms may not be negligible. Herein, recommendations for the use of earthworms and regulatory recommendations for arsenic limit standards were proposed. This study reminds us that more control and monitoring of arsenic in medicinal animals should be carried out.

Home-grown cage-free chickens were collected from two residents' backyards around the Shimen Realgar Mine, Hunan province, China, which were then analysed for arsenic (As) concentrations and its species in various organs/tissues. The total As concentrations (dry weight) are in the range as, muscle (0.82–1.23), feathers (7.05–15.80), liver (1.35–1.63), heart (1.17–1.72), stomach (1.83–3.28), stomach skin (1.99–10.58), gastric contents (12.99–20.12) and eggs (0.73–0.88) mg/kg. Dimethylarsinic acid (DMA) is the predominant As compounds determined by HPLC-ICP-MS, accounting for 76-100% of the extractable total As species in muscle, stomach, liver, heart and eggs of chicken from both backyards. Inorganic As was the main As species (23–82%) in stomach skin, gastric contents and feathers. Besides, AsB and an unknown As compounds were detected in most of the samples, although in relatively low proportions (<13.90%). Further analysis of the X-ray absorption near edge structure (XANES) provides additional information about the non-extractable and unidentified As form such as As(III)-tris-glutathione (As(III)-GSH). The estimated daily intake of As is acceptable, the corresponding hazard quotient values indicate that consumption of the chicken from the realgar mine may pose little health risks to consumers. [ABSTRACT FROM AUTHOR]

Exchangeable copper (CuEXC), mainly comprised copper (Cu) bound to albumin, has been proposed as a specific marker of Cu overload in Wilson's disease (WD). To the author's knowledge, there are no methods capable of determining reliably CuEXC to meet the requirements and challenges faced by a clinical trial. The present work describes a novel speciation strategy for the determination of the main Cu-species in human serum by anion-exchange high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (HPLC-ICP-MS). A label-free protein quantification approach was conducted where the concentration of Cu associated to the protein fraction was based on its relative peak area distribution and the total Cu concentration in the sample. Such a methodology was characterized in terms of selectivity, sensitivity, precision, and robustness. Due to the lack of speciated Cu-reference materials, protein recovery was assessed by comparison with that of species-specific (SS) isotope dilution (ID). For this, a double SS HPLC-ICP-IDMS method for Cu-albumin was developed and presented here for the first time. Three human sera (two frozen LGC8211 and ERM®-DA250a, and the lyophilised Seronorm™ Human) were analyzed using both the relative and ID quantification methods. The validated relative approach, with relative expanded uncertainties (k = 2) between 5.7 and 10.1% for Cu-albumin concentrations ranging from 112 to 455 μg kg−1 Cu, was found to be able to discriminate between healthy and WD populations in terms of Cu-albumin content. Also, using such methodology, underestimation of CuEXC by the classical EDTA/ultrafiltration method was demonstrated. The methodology developed in this work will be invaluable for quality control assessment and WD drug monitoring. [ABSTRACT FROM AUTHOR]

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To ensure reasonable intake of selenium for humans and provide insights on the development and nutritional analysis of high-quality selenium-enriched food, we established a reliable and highly sensitive method for the determination of selenium species in Z0206 selenium-enriched polysaccharide (Se-EPS). By optimizing the pre-treatment conditions (different enzymes, enzyme combinations, enzymatic time, concentration of enzymes, and centrifugation time), we found that Se-EPS can be effectively hydrolyzed by proteinase K for 18 h, followed by HPLC-ICP-MS determination. The developed method presented high sensitivity with the limit of detection and quantitation in the range of 0.44–2.35 μg L−1 and 1.54–7.21 μg L−1. The relative standard deviation (RSD) was all less than 10% and recovery was greater than 80% except for SeCys2, which further validated the repeatability and accuracy of the proposed method. Under the optimized conditions, we could determine 4 selenium species: elemental selenium (78.37%), seleno-methionine (14.27%), selenocystine (0.03%), and Se-methylselenocysteine (5.22%) in Se-EPS. This work provides new insights into the determination of different selenium species in selenium-enriched food. [ABSTRACT FROM AUTHOR]

The study aims to clarify the current controversy related to conflicting reports on whether presence of Cr(VI) in rice is possible or not. For this purpose, a method was employed for the single run speciation analysis of Cr(III) and Cr(VI) in rice samples using species-specific isotope dilution (SS-ID) and high performance liquid chromatography coupled to inductively coupled mass-spectrometry (HPLC-ICP-MS) and selective single run species complexation/derivatisation. The quantification limits (LOQs) were 0.014 μg kg−1 for Cr(III) and 0.047 μg kg−1 for Cr(VI), while the detection limits (LODs) were 0.004 and 0.014 μg kg−1 for Cr(III) and Cr(VI), respectively. A total of 10 rice samples of different origin and colour (depending on the type of industrial processing) were analysed in this study. The content of Cr(VI) was below the limit of quantification in all of the rice samples analysed, while the Cr(III) levels ranged between 0.59 (whole grain rice) up to 104 µg kg−1 (brown rice). All samples were also analysed for their total Cr (Crtotal) content by ICP-MS solely and the results were in all cases comparable with the Cr(III) levels determined in the same samples. To assess the stability of Cr(III) and Cr(VI) in rice, one sample was spiked with Cr(III) and Cr(VI) (individually) at different levels (5.0, 10, 15 and 20 μg kg−1), held for 2 h, and then analysed by SS-ID HPLC-ICP-MS. The results showed a complete reduction of Cr(VI) to Cr(III), while Cr(III) remained stable at all spiking levels. These findings support the general statement from the European Food Safety Authority related to the complete absence of Cr(VI) in foods and confirms that Cr in rice is found solely as Cr(III) species. [ABSTRACT FROM AUTHOR]