Determination of Arsenic Species in Edible Insects by LC-ICP-MS.

BACKGROUND: Edible insects may contain arsenic. Analysis of arsenic species is necessary in order to accurately assess arsenic exposure. OBJECTIVE: An analytical method was validated and used to determine and quantitate arsenic species in edible insects. METHODS: Arsenic species were extracted from edible insects by heating at 100°C in 0.3 mol/L nitric acid. The concentration of arsenic species was then determined by LC-inductively coupled plasma-mass spectrometry (LC-ICP-MS) using an octadecylsilane (ODS) column with a mobile phase containing an ion-pair reagent. RESULTS: The LOD (0.007-0.012 mg/kg), LOQ (0.021-0.038 mg/kg), repeatability (1.2-3.2%), intermediate precision (2.8-4.5%), and trueness (recoveries 97-102% based on spiked samples) of the proposed method were satisfactory for inorganic arsenic, dimethylarsinic acid (DMA), and arsenobetaine (AB) in edible insects. Total arsenic was detected in all samples obtained in Japan (Asian forest scorpion, diving beetles, giant water bug, grasshoppers, June beetles, mole crickets, male rhino beetle, female rhino beetle, sago worms, and silkworm pupae) and consisted of mostly inorganic arsenic. Beetles in particular showed relatively high levels. CONCLUSION: Arsenic content varies among edible insect species. Feed control is important, as arsenic concentrations in edible insects may be feed dependent. HIGHLIGHTS: Arsenic species in edible insects were analyzed by LC-ICP-MS using an ODS column with a mobile phase containing an ion-pair reagent. Inorganic arsenic was detected in most samples, with concentrations ranging from <0.04 to 29.3 mg/kg.

Arsenic speciation in rice samples for trace level determination by high performance liquid chromatography-inductively coupled plasma-mass spectrometry.

Six arsenic species, namely arsenite (AsIII), arsenate (AsV), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine (AsB) and arsenocholine (AsC) were speciated using a combination of high-performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS). Under optimum chromatographic conditions, six arsenic species were well separated, and the performance of the combined system (HPLC-ICP-MS) for the species was determined. The limits of detection were calculated in the range of 0.14-0.29 ng/mL, and the corresponding quantification limits ranged between 0.45 and 0.97 ng mL-1 for the species. Spike recovery experiments performed on rice samples were used to validate the method's applicability to complex matrices. The recovery results calculated ranged between 93 and 109%, validating the method's applicability. Triplicate measurements for all spiked samples recorded percent relative standard deviation values below 10%.

Dietary intake and urinary excretion of methylated arsenicals of Japanese adults consuming marine foods and rice.

Dietary intake and urinary excretion of monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and arsenobetaine (AsB) were measured in 150 adult Japanese subjects. Duplicate diet (DD) samples and first void of urine on the next morning of DD sampling day were collected and analysed for arsenic species with liquid chromatography-ICP mass spectrometry. Median (min-max) intakes of MMA, DMA and AsB were <2.3 (<2.3-<2.3), 4.57 (<2.3-24.3), and 13.6 (<2.4-231) µg As/day, respectively, and median urinary concentrations were 1.90 (<0.37-26.), 21.9 (<0.27-141) and 19.6 (<0.37-1063) ng As/mg creatinine, respectively. Interrelationships between intake levels and urinary concentrations were mostly significant with positive coefficients indicating mutual association due to co-exposure, metabolism and/or dietary habit. Urinary concentrations and intake levels of AsB were also positively correlated confirming the applicability of urine analysis as biomarker of exposure. The present descriptive results provide with essential piece of information in assessing health risk of methylated arsenicals for population who consume marine products and rice.

Inorganic arsenic influences cell apoptosis by regulating the expression of MEG3 gene.

Arsenic is a wildly distributed carcinogen in the environment. Arsenic-induced apoptosis has been extensively studied in therapeutics and toxicology. LncRNA MEG3 has been extensively studied as apoptosis regulatory gene in recent years. However, it stays unclear regarding how the mechanism of MEG3 regulates arsenic-induced apoptosis. Our focus was to explore the effects of MEG3 on arsenic-induced apoptosis. MTS assay was used to test cell viability, and qRT-PCR was for the examination of gene expressions. The effect of the apoptosis and necrosis after knockdown MEG3 was detected with double staining. Our results demonstrated that MEG3 expression was positively correlated with the concentration of three arsenic species (inorganic arsenic (iAs), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)) (p < 0.05). The ability of iAs to induce MEG3 expression was much higher compared with that induced by MMA and DMA. In addition, our experiments confirmed that MEG3 knockdown increased cell viability and arsenic-induced apoptosis, but cell viability decreased after iAs treatment. Moreover, LncRNA MEG3 regulated apoptosis via down-regulate API5 while up-regulate CASP7, CCND3 and APAF1. It is further proved that arsenic-induced apoptosis increased after the knockdown of MEG3, which regulates these genes. These findings provide experimental evidence and possible mechanisms for subsequent research on the effects of arsenic on health.

Reducing the cadmium, inorganic arsenic and dimethylarsinic acid content of rice through food-safe chemical cooking pre-treatment.

Cadmium, inorganic arsenic and, potentially, dimethyl arsenic acid are carcinogens widely elevated in rice. Here it was identified that the food-safe and common cadmium chelator citric acid efficiently removed cadmium from intact grain via pre-soaking procedure, while also reducing arsenic species. A twostep pre-soaking stage was developed whereby rice was first incubated, at ambient temperature, in 1 M citric acid for 12 h, and then in 1 M calcium carbonate for another 12 h, the latter step to neutralize pH, followed by cooking. When 10 different individual types of rice were processed in such a way this resulted in removal rates of 79% for cadmium, 81% for inorganic arsenic and a 66% for DMA. The technology is particularly suitable for bulk food processing and could be deployed in the most cadmium and arsenic impacted regions where rice is a staple.

CRM rapid response approach for the certification of arsenic species and toxic trace elements in baby cereal coarse rice flour certified reference material BARI-1.

With recently legislated maximum levels of inorganic arsenic (iAs) in white and brown rice in Canada, the regulatory bodies are evaluating the need for regulation of As levels in infant food products. Rice is a major part of infants' diet, and therefore, the presence of As in this staple food causes concerns. So far, the scientific community was lacking suitable certified reference material (CRM) which could be used to assess the accuracy of developed analytical methods for As speciation in infants' food products. As a result, we have developed BARI-1, a baby cereal coarse rice flour reference material which was certified for total arsenic (0.248 ± 0.018 mg kg-1), cadmium (0.0134 ± 0.0014 mg kg-1), mercury (0.0026 ± 0.0003 mg kg-1), lead (0.0064 ± 0.0016 mg kg-1), inorganic As (0.113 ± 0.016 mg kg-1) and dimethylarsinic acid (DMA) (0.115 ± 0.010 mg kg-1), and reference value for monomethylarsonic acid (MMA) (0.0045 ± 0.0008 mg kg-1) was reported. We also observed trace amounts of an unknown As compound, with chromatographic retention time close to DMA. Participating laboratories were allowed to use their in-house-validated extraction and/or digestion methods, and the detection of total metals was done by ICP-MS whereas HPLC-ICP-MS was used for As speciation. Despite the diversity in sample preparation and quantitation methods, reported values were in good agreement. For iAs measurement, the comparison between hydride generation ICP-MS and HPLC-ICP-MS found iAs overestimation with the former method, possibly due to interference from DMA. The certification was accomplished with a CRM rapid response approach in collaborative, focused effort completing the CRM development in few months instead of the typical multiyear project. This approach allowed to respond to measurement needs in a timely fashion. Graphical abstract.

Arsenic fractionation in sediments and speciation in muscles of fish, Chrysichthys nigrodigitatus from a contaminated tropical Lagoon, Nigeria.

This study assesses arsenic (As) fractionation in sediments and speciation in muscle tissues of Bagrid catfish, Chrysichthys nigrodigitatus from Lagos Lagoon, southwest Nigeria to determine risks to ecological receptors and humans. Residual As was the predominant geochemical fraction (86.2%) in sediments. Arsenite [As (III)] concentrations which ranged from 0.06 to 0.53 mg kg-1 in catfish muscle tissue, accounting for 25.9% of total As was the dominant species. Less toxic dimethylarsinic acid (DMA) which varied between 0.06 and 0.27 mg kg-1 made up to 10.8% of total As in catfish muscle tissue. Estimated human average daily intake (ADI) of As as As (III) and DMA were 1.35 × 10-4 and 0.62 × 10-4 mg kg-1 BW with corresponding hazard quotients (HQs) of 0.45 and 0.21, respectively, indicate no apparent health hazard to adult consumers. The incremental lifetime cancer risks (ILCR) of 0.78 × 10-3 for total As, 0.20 × 10-3 for As (III), and 0.93 × 10-3 for DMA, for adults from the consumption of catfish is slightly higher than the US EPA threshold and indicates moderate carcinogenic risk. Furthermore, 12.5% bioavailable fraction of As in sediment and relatively higher levels of As (III) in fish tissues has ecological and public health implications.

Impact of River Water and Bottom Sediment Pollution on Accumulation of Metal(loid)s and Arsenic Species in the Coastal Plants Stuckenia pectinata L., Galium aparine L., and Urtica dioica L.: A Chemometric and Environmental Study.

The role of water and bottom sediment pollution of a river subjected to a strong industrial anthropo-pressure in coastal plants was investigated. The work presented the influence of polluted environment on accumulation of metal(loid)s (including arsenic and its species) in Stuckenia pectinata L., Galium aparine L., and Urtica dioica L. The study provided important information on the contents of organic and inorganic arsenic species in selected plants and their response to heavy metal and arsenic contamination. The As(III), As(V), AB (arsenobetaine), MMA (monomethylarsonic acid), and DMA (dimethylarsinic acid) ions were successfully separated on the Hamilton PRP-X100 column with high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) techniques. The Pollution Load Index and geo-accumulation Index (Igeo) values clearly indicate significant pollution of the examined ecosystem with heavy metals. The chemometric analysis with the concepts of (Dis)similarity Analysis, Cluster Analysis, and Principal Component Analysis helped to visualize the variability of the As species concentrations and to analyse correlations between sampling point locations and analyte contents.

Distribution patterns of arsenic species in a lichen biomonitor.

As stand-alone approaches, chromatographic separations of arsenic in lichen using HPLC-ICP-MS or the use of sequential extractions have historically been shown to have low analyte recoveries and poor analyte selectivity respectively. This study modifies the first step of a sequential extraction with a chromatographic separation of five arsenic species using HPLC-ICP-MS, followed by a three-step sequential extraction and analysis with ICP-MS. The method was applied to lichens from a rural and urban site to demonstrate the applicability thereof, and the sum of arsenic concentrations from the extraction steps were compared to the total arsenic concentrations. Short term species stability of the As species in the lichen matrix was also evaluated over 1 month in the water-extractable fraction, where As species concentrations changed week by week, providing insight into biotransformation mechanisms. In the modified extraction step, dimethylarsinic acid (DMA) and arsenobetaine and an unknown As species (AsB + U1) were statistically (p < 0.05) higher in the urban site than the rural site. Analyte recoveries using the combined method were higher than other studies reported in literature, with percentage recoveries of 104% and 111% of As in the urban and rural sites respectively. Arsenic concentrations were found in the following order of abundance at both sites: oxidizable > reducible > water-extractable > residual. Concentrations of total As in the oxidizable and non-bioavailable fraction were statistically lower (p < 0.05) in the rural site than in the urban site. Based upon the information gained from this study, we could draw concise conclusions regarding the source apportionment, timing and the magnitude of the pollution event.

Bioaccessibility of arsenic from gastropod along the Xiangjiang River: Assessing human health risks using an in vitro digestion model.

The bioaccessibility of total arsenic (tAs) and arsenic species in Bellamya aeruginosa collected from Xiangjiang River was evaluated using an in vitro digestion model, to assess the potential health risks to local residents. The tAs concentrations in gastropod samples ranged from 1.98 to 6.33 mg kg-1 (mean 3.79 ± 1.60 mg kg-1). Five arsenic species including arsenite [As(III)], arsenate [As(V)], dimethylarsinic acid (DMA), arsenobetaine (AsB), and arsenocholine (AsC) were detected. Inorganic arsenic (iAs) concentrations, which were about a half of organic arsenic (oAs), were higher than the maximum permissible limit (≤0.50 mg kg-1 in aquatic products). Bioaccessible concentrations of tAs in digestive juices were found to be decreased in the order: intestinal phase > gastric phase > salivary phase. As(III) and AsC were the predominant species, but AsB was not detectable in all digestive juices. Bioaccessible iAs concentrations, which were close to the level of bioaccessible oAs, were not significantly different among three digestive juices, but also above 0.50 mg kg-1. Accordingly, bioaccessibility of tAs was highest in intestinal phase (48%), then in gastric phase (40%), and lowest in salivary phase (33%). Bioaccessibility of As(III) was close to 100%, and bioaccessibility of iAs was much higher than that of oAs. The mean values of target hazard quotient (THQ) and bioaccessible THQ were 0.80 and 0.70, respectively. The probability of experiencing non-carcinogenic effects was reduced to 18% down from 22% as considering iAs bioaccessibility. The mean values of carcinogenic risk (CR) and bioaccessible CR were higher than the acceptable value (1 × 10-4). Gastropod consumption from sampling sites may cause a potential carcinogenic risk.

Arsenic speciation in the bracket fungus Fomitopsis betulina from contaminated and pristine sites.

Uptake, distribution and speciation of arsenic (As) were determined in the bracket fungus Fomitopsis betulina (previously Piptoporus betulinus), commonly known as the birch polypore, collected from a woodland adjacent to a highly contaminated former mine in the Southwest UK and at an uncontaminated site in Quebec, Canada, with no past or present mining activity. The fruiting body was divided into cap, centre and pores representing the top, middle and underside to identify trends in the distribution and transformation of As. Total As, determined by inductively coupled plasma-mass spectrometry (ICP-MS), was approximately tenfold higher in the mushroom from the contaminated compared to the uncontaminated site. Overall, accumulation of As was low relative to values reported for some soil-dwelling species, with maximum levels of 1.6 mg/kg at the contaminated site. Arsenic speciation was performed on aqueous extracts via both anion and cation high-performance liquid chromatography-ICP-MS (HPLC-ICP-MS) and on whole dried samples using X-ray absorption near edge structure (XANES) analysis. Seven As species were detected in F. betulina from the contaminated site by HPLC-ICP-MS: arsenite (AsIII), arsenate (AsV), dimethylarsinate (DMAV), methylarsonate (MAV), trimethylarsine oxide (TMAO), tetramethylarsonium ion (Tetra) and trace levels of arsenobetaine (AB). The same As species were observed at the uncontaminated site with the exception of TMAO and Tetra. Arsenic species were localized throughout the fruiting body at the contaminated site, with the cap and pores containing a majority of AsV, only the cap containing TMAO, and the pores containing higher concentrations of DMAV and MAV as well as tetra and a trace of AB. XANES analysis demonstrated that the predominant form of As at the contaminated site was inorganic AsIII coordinated with sulphur or oxygen and AsV coordinated with oxygen. This is the first account of arsenic speciation in F. betulina or any fungi of the family Fomitopsidaceae.

Arsenic in Sediments, Soil and Plants in a Remediated Area of the Iron Quadrangle, Brazil, and its Accumulation and Biotransformation in Eleocharis geniculata.

Since arsenic (As) exposure is largely due to geochemical contamination, this study focused on the remediated area of Santana do Morro, a district of Santa Bárbara, Minas Gerais, Brazil, which was previously contaminated with As due to gold mining. Total As concentrations in sediment, soil and plants were determined, next to As species, anionic arsenic compounds As(III), As(V), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), in plants samples. Total As concentrations in soil and sediments were slightly elevated (16-18 µg g-1) and most of the plants contained low levels of As (< 1 µg g-1). The exception was a native plant Eleocharis geniculata (L.) which contained elevated levels of As (4 µg g-1). The exposure of this plant to As under controlled conditions (hydroponics) indicated its possible tolerance to elevated As levels and suggesting its potential use in phytomonitoring of As-contaminated sites. This plant is able to metabolize arsenate to arsenite and contained MMA and DMA, both in its natural habitat and under controlled conditions.

Optimized extraction of inorganic arsenic species from a foliose lichen biomonitor.

To assess the two most toxicologically relevant species of As, namely arsenite (As(III)) and arsenate (As(V)), chromatographic separations often require two separate chromatographic columns to address the co-elution of arsenobetaine (AsB) with As(III). This issue is typically observed using conventional isocratic methods on anion exchange columns, increasing cost and analysis time. Here, we optimize the extraction of inorganic As from a lichen air biomonitor and develop an isocratic method for the chromatographic separation of five common As species on a PRP X-100 anion exchange column, resulting in the complete baseline separation of all species under study. This method was then applied to lichen biomonitors from an urban and rural site to demonstrate its use. In order of abundance, the various arsenic species in lichens from the urban site in South Africa were As(V) > As(III) > AsB > dimethylarsinic acid (DMA) > monomethylarsonic acid (MMA), and As(V) > AsB > As(III) > DMA > MMA for the rural site, where MMA was present in extremely low, non-quantifiable concentrations in lichens from both sites. Total concentrations of As were higher in samples from the urban site (6.43 ± 0.25 µg/g) than in those from the rural site (1.87 ± 0.05 µg/g), with an overall extraction efficiency of 19% and 40%, respectively. The optimized method utilized relatively inexpensive solvents and is therefore low-cost and eco-friendly in comparison with conventional chromatographic techniques. This is the first study which addresses the optimized extraction and characterization of As species in a South African lichen biomonitor of air pollution. Graphical abstract .

The use of HPLC-NAA and HPLC-ICP-MS for the speciation of As in infant food.

Arsenic and its inorganic species: As (III), As (V), dimethylarsenic acid (DMA) and monomethylarsenic acid (MMA) were determined in hypoallergenic formulas and grain porridges commercially available on Polish market, dedicated for infant 0-8 months. After quantitative extraction with 0.5% HNO3, separation of individual species was performed by high performance liquid chromatography (HPLC), and their determination by neutron activation analysis (NAA) and inductively coupled plasma mass spectrometry (ICP-MS). Due to relatively low content of As in the analysed samples, it was only possible to determine DMA using the HPLC-ICP-MS mode. HPLC separation coupled with off-line determination by NAA enabled the determination of more extracted As species (especially inorganic) with good accuracy. Certified reference material (CRM) Rice Flour SRM 1568b (NIST) was used for the validation of both procedures.

Metal(loid) speciation in a river subjected to industrial anthropopressure: chemometric and environmental studies.

High-performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was applied to the speciation of arsenic [As(III), As(V), and AsB (arsenobetaine)], MMA (monomethylarsonic acid), DMA (dimethylarsinic acid), antimony [Sb(III) and Sb(V)], and chromium [Cr(III) and Cr(VI)] in water and bottom sediment samples collected from the urban Bytomka River (Poland). The main objective of the study was the research of As, Cr and Sb species in the Bytomka River, as well as the simplified three-stage sequential chemical extraction of bottom sediments according to the Institute for Reference Materials and Measurements (BCR). The contents of V, Mn, Co, Ni, Cu, Zn, Rb, Sr, Ag, Cd, Te, Ba, Tl, Pb, Fe, Ga, and U in the water and bottom sediments were tested using the ICP-MS technique. The risk assessment code (RAC) indicated a medium risk for As and a high risk for Sb to the environment. Sequential chemical extraction of bottom sediments showed that As and Cr were strongly demobilized. Sb was mainly bound with the ion-exchange fraction and posed a serious threat to the environment. Chemometric analysis with the (dis)similarity analysis and principal component analysis (PCA) allowed for visualization of the variability and correlations of the analyzed elements.

On the Use of Hair Analysis for Assessing Arsenic Intoxication.

Correlations between the concentrations of arsenic in scalp hair and in drinking water as well as in blood and/or urine have been reported. These correlations clearly show exposure⁻absorption⁻excretion relationships. In addition, arsenic metabolites such as monomethylarsonic acid and dimethylarsinic acid have been identified and quantified in these tissues and fluids, leaving little doubt that elevated levels of arsenic in the hair can reflect systemic arsenic intoxication. Consequently, hair analysis has potential merit as a screening procedure for poisoning by arsenic. However, questions regarding the exogenous versus the endogenous deposition of arsenic in the hair, and uncertainties about the normal level of arsenic in the hair remain unresolved. Pending their resolution, the determination of arsenic in hair should remain a screening tool, and clinical signs and symptoms should be employed to complete the diagnosis of arsenic poisoning.

Pharmacokinetic Properties of Arsenic Species after Intravenous and Intragastrical Administration of Arsenic Trioxide Solution in Cynomolgus Macaques Using HPLC-ICP-MS.

A rapid and sensitive method was established for arsenic (As) speciation based on high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (HPLC-ICP-MS). This method was validated for the quantification of four arsenic species, including arsenite (AsIII), arsenate (AsV), monomethylarsonic acid (MMAV) and dimethylarsinic acid (DMAV) in cynomolgus macaque plasma. Separation was achieved in just 3.7 min with an alkyl reverse phase column and highly aqueous mobile phase containing 20 mM citric acid and 5 mM sodium hexanesulfonate (pH = 4.3). The calibration curves were linear over the range of 5⁻500 ng·mL-1 (measured as As), with r > 0.99. The above method was validated for selectivity, precision, accuracy, matrix effect, recovery, carryover effect and stability, and applied in a comparative pharmacokinetic study of arsenic species in cynomolgus macaque samples following intravenous and intragastrical administration of arsenic trioxide solution (0.80 mg·kg-1; 0.61 mg·kg-1 of arsenic); in addition, the absolute oral bioavailability of the active ingredient AsIII of arsenic trioxide in cynomolgus macaque samples was derived as 60.9 ± 16.1%.

Effect of roxarsone metabolites in chicken manure on soil biological property.

Roxarsone (ROX), an organoarsenic feed additive, occurs as itself and its metabolites including As(V), As(III), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) in animal manure. Animal manure improves soil biological property, whereas As compounds impact microorganisms. The integral influence of animal manure bearing ROX metabolites on soil biological quality is not clear yet. Herein, the effect of four chicken manures excreted by chickens fed with four diets containing 0, 40, 80 and 120 mg ROX kg-1, on soil biological attributes. ROX addition in chicken diets increased total As and ROX metabolites in manures, but decreased manure total N, ammonium and nitrate. The elevated ROX metabolites in manures increased soil total As, As species and total N, and increased first and then decreased soil nitrate and nitrite, but did not affect soil ammonium in manure-applied soils. The promoting role of both soil As(III) and ammonium on soil microbial biomass carbon and nitrogen, respiration and saccharase activity, were exceeded or balanced by the inhibiting effect of soil nitrate. The suppression of soil catalase activity by soil As(V) was surpassed by the enhancement caused by soil nitrate and nitrite. Soil urease, acid phosphatase and polyphenol oxidase activities were not suitable bioindicators in the four manure-amended soils. Soil DMA did not affect soil biological properties, and MMA was not detectable in all manure-amended soils. The above highlights the complexity of joint influence of soil As and N on biological attributes. Totally, when ROX is used at allowable dose in chicken diet, soil biological quality would be suppressed in manure-amended soil.

Arsenic accumulation, distribution and source analysis of rice in a typical growing area in north China.

Rice (Oryza sativa) is believed to be a major source of arsenic (As) exposure in humans, especially in Asia. In this study, As accumulation, distribution and source analysis of rice are investigated in five sites (SZ, QH, XZ, WS and JX) in the Nansi Lake area, an important rice-growing region in north China. Findings show that total As average concentrations were 6.3-13.6 mg kg-1 and 5.5-9.9 µg L-1 in paddy soil and irrigation water, respectively. Inorganic arsenic As(III) and dimethylarsinic acid DMAs(V) were the major speciation in polished rice, with a small proportion of As(V) evident. Notably, the percentage of As(III) increased by 63.9-68.5%. Based on survey data, the addition of total As to farm soil due to fertilizer application was 31.5-11,580 mg per hectare per year. According to the results of Spearman's rank correlation analysis and Principal Component Analysis (PCA), As levels in soil and irrigation water may be important factors influencing As concentration in rice.

Total As and As speciation from worldwide collected red wine samples.

Total As and As speciation were measured in 147 red wines collected worldwide by ICP-MS and HPLC-ICP-MS, respectively. The samples included mid-priced to prestigious wines with vintages covering a period of almost 50 years. Total As concentration ranged from below 0.1 to 56 µg/L (average value: 4.0 ± 5.9 µg/L). None of the samples presented a concentration exceeding the limit set by the Office of Vine and Wine of 200 µg/L. Inorganic As was the most abundant form, representing from about half to all total As, mainly as As(III). Dimethylarsinic-acid (DMA) was detected in slightly less than half of the samples, accounting for a few to several dozens of percent. Monomethylarsonic-acid (MMA) was only detected in a few samples. In average, the DMA concentration seemed to be higher in the Bordeaux wines than in the other ones, irrespective of the total As concentration.