Ionic Liquid Modified Polymer Gel for Arsenic Speciation.

A new ionic liquid modified polymer gel containing methylimidazolium groups (poly(MIA)) is proposed as a sorbent for the separation and enrichment of trace inorganic and organic arsenic species in surface waters. The poly(MIA) was synthesized by chemical modification of polymeric precursor using post-polymerization modification of poly(glycidyl methacrylate-co-trimethylolpropane trimethacrylate). The composition, structure, morphology, and surface properties of the prepared particles were characterized using elemental analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and nitrogen adsorption-desorption measurements. Optimization experiments showed that at pH 8, monomethylarsonic acid (MMAs), dimethylarsinic acid (DMAs), and As(V) were completely retained on the poly(MIA), while the sorption of As(III) was insignificant. The desorption experiments revealed that due to the weaker binding of organic arsenic species, selective elution with 1 mol/L acetic acid for MMAs + DMAs, followed by elution with 2 mol/L hydrochloric acid for As(V), ensured their quantitative separation. The adsorption kinetic and mechanism were defined. The analytical procedure for As(III), As(V), MMAs, and DMAs determination in surface waters was developed and validated through the analysis of certified reference material.

[Correlation analysis of urinary arsenic species and health effect indicators of occupational arsenic exposure workers].

Objective: To explore the correlation between urinary arsenic and health effects through the determination and analysis of urinary arsenic levels in occupational arsenic exposed workers. Methods: In November 2021, 95 workers exposed to arsenic and its inorganic compounds and 31 administrative personnel from a non-ferrous metal smelter in Yunnan Province were selected as the contact group and control group, respectively. Urine forms of arsenic, blood tumor markers, liver function were detected, and micronucleus test was used to analyze the chromosome damage. The correlation between urine forms of arsenic and health effects were analyzed. Results: Compared with the control group, the concentrations of urinary trivalent inorganic arsenic (iAs(3+)) , pentavalent inorganic arsenic (iAs(5+)) , inorganic arsenic (iAs=ΣiAs(3+)+iAs(5+)) , monomethyl arsenic (MMA) , dimethyl arsenic (DMA) and urinary arsenic (ΣiAs+MMA+DMA) at the end of class in contact group were higher (P<0.05) . There was no statistically significant difference in blood tumor markers and liver function indicators between the two groups (P>0.05) . Compared with the control group, the peripheral blood micronucleus rate and cell micronucleus rate in the contact group were significantly increased (P<0.05) . The urinary arsenic, iAs(5+), inorganic arsenic and DMA were positively correlated with peripheral blood micronucleus rate in contact group (r(s)=0.48, 0.34, 0.37, 0.23, P<0.05) , and the urinary arsenic, iAs(5+), DMA were positively correlated with peripheral blood micronucleus rate (r(s)=0.48, 0.34, 0.26, P<0.05) . Conclusion: There is a significant correlation between different valence states of arsenic in the urine and abnormal health effects of occupational arsenic exposed workers. It is necessary to strengthen the detection of arsenic species in the urine of occupational arsenic exposed workers to better protect their health.

Species-specific arsenic species and health risk assessment in seaweeds from tropic coasts of South China Sea.

Arsenic (As) is a notorious toxic contamination in marine environments, while the toxicity and health risk of As is highly dependent on As species in seafoods. In this study, we hypothesized that the species-specific As bioaccumulation and species resulted in species-specific healthy risk of As in seaweeds. To test the hypothesis, we collected 10 common edible seaweeds from the coast of Hainan Island in South China Sea. Then we comparatively quantified concentration of total As and 5 major As species [AsB, DMA, MMA, As(III), and As(V)] in seaweeds. The results revealed that the concentrations of total As varied significantly among 10 seaweed species. Specially, the highest total As concentration were found in brown seaweeds, followed by red seaweeds, and green seaweeds. Furthermore, the percentage of 5 As species to total As differed significantly among 10 seaweeds. The percentage of AsB was highest in Caulerpa lentillifera (53%) and lowest in Sargassum oligocystum (13%), while that of As(V) was lowest in Caulerpa lentillifera (21%) and highest in Sargassum oligocystum (81%). The iAs [As(III) + As(V)] exhibited highest value in brown seaweeds and least value in green seaweeds. The potential human health risk assessment indicated that the consumption of brown seaweeds of Sargassum oligocystum and Sargassum polycystum could cause a considerable carcinogenic risk and non-carcinogenic risk to residents. Overall, our findings here largely validated our hypothesis that the species-specific As bioaccumulation and As species had great significance to healthy risk of As in seaweeds.

Concentrations of blood and urinary arsenic species and their characteristics in general Korean population.

Arsenic (As) exposure has been extensively studied by investigating As species (e.g., inorganic arsenic (iAs), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA)) in urine, yet recent research suggests that blood could be a possible biomarker of As exposure. These investigations, however, were conducted on iAs-contaminated areas, and evidence on populations exposed to low levels of iAs is limited. This study aimed to describe the levels and distributions of As species in urine and blood, as well as to estimate methylation efficiency and related factors in the Korean population. Biological samples were obtained by the Korean Ministry of Food and Drug Safety. A total of 2025 urine samples and 598 blood samples were utilized in this study. Six As species were measured using ultra-high-performance liquid chromatography with inductively coupled plasma mass spectrometry (UPLC-ICP-MS): As(V), As(III), MMA, DMA, arsenobetaine (AsB), and arsenocholine (AsC). Multiple linear regression models were used to examine the relationship between As species (concentrations and proportions) and covariates. AsB was the most prevalent species in urine and blood. The relative composition of iAs, MMA, DMA, and AsC in urine and blood differed significantly. Consumption of blue-backed fish was linked to higher levels of AsB in urine and blood. Type of drinking water and multigrain rice consumption were associated with increased iAs concentration in urine. Except for iAs, every species had correlations in urine and blood in both univariate and multivariate analyses. Adolescents and smokers presented a lower methylation efficiency (higher %MMA and lower %DMA in urine) and females presented a higher methylation efficiency (lower %iAs, %MMA, and higher %DMA in urine). In conclusion, blood iAs concentration cannot represent urinary iAs; nonetheless, different compositions of urine and blood might reflect distinct information about iAs exposure. Further investigations on exposure factors and health are needed using low-exposure groups.

Spatial distribution and health risk assessment of As and Pb contamination in the groundwater of Rayong Province, Thailand.

This study investigates the presence of arsenic (As) and lead (Pb) in groundwater and their spatial distribution in Ban Khai District, Rayong Province, Thailand. Forty groundwater samples were collected at different locations in the dry and wet seasons during March and August of 2019, respectively. The hydrochemical facies illustrate that the major groundwater types in both seasons mainly consisted of Ca-Na-HCO3, Ca-HCO3-Cl and Na-HCO3 types. The concentration of As ranged from <0.300 to 183.00 µg/L, accounting for 22% (18 of 80 samples), exceeding the WHO guidelines of 10 µg/L. The spatial distribution of As was distinctly predominant as a hot spot in some areas during the wet season. The wells may have been contaminated from human activity and thus constituted a point source in the adjacent area. For Pb, its concentration in all the wells were not exceeded 10 µg/L of the WHO guidelines, appearing as a background concentration in this area. Most of the wells were shown to be in an oxidation state, supporting AsV mobility. Moreover, the area also had a nearly neutral pH that promoted AsV desorption, while the presence of undissolved Pb in the aquifers tended to increase. Furthermore, chemical applications to agricultural processes could release the As composition into the groundwater. The health risk resulting from oral consumption was at a higher risk level than dermal contact. The non-carcinogenic risk affecting the adult population exceeded the threshold level by approximately 27.5% of the wells, while for the children group, the risk level was within the limit. Total cancer risk (TCR) of adult residents exceeded the acceptable risk level (1 × 10-6) in all wells, causing carcinogenic health effects. Therefore, health surveillance is important in monitoring the toxic effects on the local residents who use groundwater from these contaminated wells. Furthermore, a sanitation service and an alternative treatment of the water supply will be needed, especially in wells with high As levels.

Supergene geochemistry of arsenic and activation mechanism of eucalyptus to arsenic source.

Arsenic (As) migration and transformation in the supergene environment and eucalyptus planting have essential effects on ecology or even human health, respectively. However, the combined environmental impact of As migration and transformation and eucalyptus planting has not been studied. Here we report a case of soil As contamination caused by eucalyptus planting and address the fate of As in Longmen county, Guangdong Province, China. We found high As content in weathered arsenopyrite bearing granite or granite-derived soil, where a large area of eucalyptus is planted. The release of organic acids from eucalyptus roots promoted the electrochemical reaction of arsenopyrite to produce AsO33-. In the subsequent supergene migration process, As species change from arsenite to arsenate with the addition of oxygen and the effect of clay minerals, last with As infiltration, precipitation, and enrichment, forming the As contamination in soil. The whole process reveals the activation process of eucalyptus to the As source (arsenopyrite), the migration and transformation process of As in the supergene environment, and the formation mechanism of soil As contamination. This finding provides a new perspective of soil As contamination around arsenopyrite bearing granite of the Nanling area with eucalyptus planting and proposes that the negative effects of Nanling eucalyptus planting may be greater than expected.

[Content and distribution of inorganic elements in Laminaria japonica based on ICP-MS and Micro-XRF].

In order to evaluate the composition and distribution characteristics of inorganic elements in Laminaria japonica, this study employed inductively coupled plasma mass spectrometry(ICP-MS) to detect the inorganic elements and used high performance liquid chromatography tandem ICP-MS(HPLC-ICP-MS) to determine the content of different arsenic species in L. japonica from diffe-rent origins. Micro X-ray fluorescence(Micro-XRF) was used to determine micro-area distribution of inorganic elements in L. japonica. The results showed that the average content of Mn, Fe, Sr, and Al was high, and that of As and Cr exceeded the limits of the national food safety standard. According to the results of HPLC-ICP-MS, arsenobetaine(AsB) was the main species of As contained in L. japonica. The more toxic inorganic arsenic accounts for a small proportion, whereas its content was 1-4 times of the limit in the national food safety standard. The results of Micro-XRF showed that As, Pb, Fe, Cu, Mn, and Ni were mainly distributed on the surface of L. japonica. Among them, As and Pb had a clear tendency to diffuse from the surface to the inside. The results of the study can provide a basis for the processing as well as the medicinal and edible safety evaluation of L. japonica.

Ti (IV) modified vinyl phosphate magnetic nanoparticles for simultaneous preconcentration of multiple arsenic species from chicken samples followed by HPLC-ICP-MS analysis.

Ti (IV)-modified vinyl phosphate magnetic nanoparticles (Fe3 O4 @SiO2 @KH570-PO4 -Ti (IV)) was prepared for simultaneous extraction of multiple arsenic species, followed by high performance liquid chromatography (HPLC)- inductively coupled plasma mass spectrometry (ICP-MS) analysis. Inorganic arsenic (iAs), dimethyl arsenic acid (DMA), monomethyl arsenic acid (MMA), p-amino phenyl arsenic acid (p-ASA), 4-hdroxyphenylarsenic acid (4-OH), phenyl arsenic acid (PAA), and 3-nitro-4-hydroxyphenylarsenic acid (ROX) were investigated as interest analytes. It was found that they were quantitatively adsorbed on Fe3 O4 @SiO2 @KH570-PO4 -Ti (IV) at pH 5, and desorbed completely with 0.1 mol/L sodium hydroxide solution. Enrichment factor of 100-fold was obtained by consuming 100 mL sample solution. Under the optimal conditions, the method combining MSPE with HPLC-ICP-MS presented a linear range of 1-5000 ng/L for seven arsenic species. The limits of detection were 0.39, 0.60, 0.23, 1.85, 0.54, 0.48, and 0.84 ng/L for DMA, MMA, p-ASA, iAs, 4-OH, PAA, ROX, with the relative standard deviations (c = 10 ng/L, n = 7) of 3.6, 3.9, 5.5, 12.4, 6.1, 5.8, 5.0, respectively. The accuracy of the method was validated by analyzing BCR 627 Tuna fish. The application potential of the method was further evaluated by chicken muscle and liver samples. No target arsenic species were detected in these samples, and good recoveries (80.6-123%) were obtained for the spiked samples at low, medium, and high concentration levels.

Characteristics of arsenic species in cerebrospinal fluid (CSF) of acute promyelocytic leukaemia (APL) patients treated with arsenic trioxide plus mannitol.

Arsenic speciation in cerebrospinal fluid (CSF) is critical for treatment/prevention of central nervous system (CNS) relapse in acute promyelocytic leukaemia (APL) patients treated with arsenic trioxide (ATO). Previous study showed low total arsenic level in CSF of APL patients. Mannitol infusion was applied to improve blood-brain barrier (BBB) permeability for arsenic. Arsenite (AsIII ), monomethylarsonic acid (MMAV ), dimethylarsinic acid (DMAV ), and arsenate (AsV ) in CSF and plasma were analysed by high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS). The profile and concentration of arsenic species in CSF from APL patients administered ATO alone and in combination with mannitol were compared. The overall distribution trend of arsenic species in CSF was AsIII , DMAV > MMAV > AsV . Arsenicals accumulated in CSF with administration frequency. The permeability of BBB for AsIII was higher than that for MMAV and DMAV . Arsenic concentration in CSF was much lower than that in plasma. There were significantly higher arsenic species concentrations in CSF of APL patients treated with mannitol than that without mannitol. Mannitol infusion significantly increased AsIII penetration into CSF, which was beneficial to optimize efficacy in APL patients with CNS relapse.

Roxarsone transformation and its impacts on soil enzyme activity in paddy soils: A new insight into water flooding effects.

The aromatic arsenical roxarsone (ROX) has been used as feed additive for decades worldwide. The past or present application of animal manure containing ROX in paddy fields results in arsenic (As) accumulation in rice grain. However, the degradation and transformation mechanisms of ROX in paddy soil which determine As bioavailability and uptake by rice are still unclear. The current study investigated the variation of As speciation and soil enzyme activities in ROX-treated soils under flooded and non-flooded conditions for six months. Our results showed that 70.2% of ROX persisted in non-flooded paddy soils after 180 d while ROX degraded completely within 7 d in flooded soils. The rapid degradation of ROX under flooded conditions owed to the enhanced biotic transformation that was caused by the low Eh and the predominant presence of Clostridium spp. and Bacillus spp. ROX was not only transformed to As(III) and As(V) in non-flooded soils but also to 3-amino-4-hydroxyphenylarsonic acid and methyl arsenicals in flooded soils. The degradation products significantly inhibited soil enzyme activities for 7-30 d, but the inhibition effects disappeared after 90 d due to the sorption of transformed As products to amorphous Fe oxides. This study provides new insights into the flooding effect on ROX fate in paddy fields, which is important for the management of animal waste and risk control on polluted sites.

Arsenic accumulation and speciation in two cultivars of Pteris cretica L. and characterization of arsenate reductase PcACR2 and arsenite transporter PcACR3 genes in the hyperaccumulating cv. Albo-lineata.

Pollution and poisoning with carcinogenic arsenic (As) is of major concern globally. Interestingly, there are ferns that can naturally tolerate remarkably high As concentrations in soils while hyperaccumulating this metalloid in their fronds. Besides Pteris vittata in which As-related traits and molecular determinants have been studied in detail, the As hyperaccumulation status has been attributed also to Pteris cretica. We thus inspected two P. cretica cultivars, Parkerii and Albo-lineata, for As hyperaccumulation traits. The cultivars were grown in soils supplemented with 20, 100, and 250 mg kg-1 of inorganic arsenate (iAsV). Unlike Parkerii, Albo-lineata was confirmed to be As tolerant and hyperaccumulating, with up to 1.3 and 6.4 g As kg-1 dry weight in roots and fronds, respectively, from soils amended with 250 mg iAsV kg-1. As speciation analyses rejected that organoarsenical species and binding with phytochelatins and other proteinaceous ligands would play any significant role in the biology of As in either cultivar. While in Parkerii, the dominating As species, particularly in roots, occurred as iAsV, in Albo-lineata the majority of the root and frond As was apparently converted to iAsIII. Parkerii markedly accumulated iAsIII in its fronds when grown on As spiked soils. Considering the roles iAsV reductase ACR2 and iAsIII transporter ACR3 may have in the handling of iAs, we isolated Albo-lineata PcACR2 and PcACR3 genes closely related to P. vittata PvACR2 and PvACR3. The gene expression analysis in Albo-lineata fronds revealed that the transcription of PcACR2 and PcACR3 was clearly As responsive (up to 6.5- and 45-times increase in transcript levels compared to control soil conditions, respectively). The tolerance and uptake assays in yeasts showed that PcACRs can complement corresponding As-sensitive mutations, indicating that PcACR2 and PcACR3 encode functional proteins that can perform, respectively, iAsV reduction and membrane iAsIII transport tasks in As-hyperaccumulating Albo-lineata.

Influence of Humic Acid on Oxidative Stress Induced by Arsenite and Arsenate Waterborne Exposure in Danio rerio.

The studies on how humic acid (HA) influences the oxidative stress of arsenic in aquatic organism is limited. Using Danio rerio as case study, we explored the oxidative stress effects in aquatic organism after 96 h exposure to the HA and arsenic. Results revealed the co-exposure of HA and arsenite elevated the superoxide dismutase activities and downgraded the malondialdehyde. Thus, we speculate that HA may alleviate the oxidative stress induced by arsenite, which may be caused by the HA's coating in combination with the complexation of arsenite and HA. In addition, HA acted as the reactive oxygen species scavenger, promising to eliminate the oxygen free radicals. Contrastingly, HA may impact little on the arsenate exposure. This study can help better understand oxidative stress mechanism of co-exposure of arsenic and HA in aquatic environment.

First Extensive Polyphenolic Profile of Erodium cicutarium with Novel Insights to Elemental Composition and Antioxidant Activity.

Erodium cicutarium is known for its total polyphenolic content, but this work reveals the first highly detailed profile of E. cicutarium, obtained with UHPLC-LTQ OrbiTrap MS4 and UHPLC-QqQ-MS/MS techniques. A total of 85 phenolic compounds were identified and 17 constituents were quantified. Overall, 25 new compounds were found, which have not yet been reported for the Erodium genera, or the family Geraniaceae. Along with methanolic extracts, the so far poorly investigated water extracts exhibited in vitro antioxidant activity according to all performed assays, including the ferric reducing/antioxidant power assay (FRAP), 2,2-diphenyl-1-picrylhydrazyl assay (DPPH), 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) assay (ABTS) and cupric ion reducing antioxidant capacity assay (CUPRAC). Elemental composition analysis performed with inductively coupled plasma atomic emission spectrometry (ICP-AES) and, additionally, hydride generation atomic absorption spectrometry (HydrEA-ETAAS) showed six most abundant elements to be decreasing as follows: Mg>Ca>K>S>P>Na, and gave first data regarding inorganic arsenic content (109.3-248.4 ng g-1 ). These results suggest E. cicutarium to be a valuable source of various phenolic compounds with substantial potential for further bioactivity testing.

Non-chromatographic Speciation of As by HG Technique-Analysis of Samples with Different Matrices.

The applicability of the hydride generation (HG) sample introduction technique combined with different spectrochemical detection methods for non-chromatographic speciation of toxic As species, i.e., As(III), As(V), dimethylarsinate (DMA) and monomethylarsonate (MMA), in waters and other environmental, food and biological matrices is presented as a promising tool to speciate As by obviating chromatographic separation. Different non-chromatographic procedures along with speciation protocols reported in the literature over the past 20 year are summarized. Basic rules ensuring species selective generation of the corresponding hydrides are presented in detail. Common strategies and alternative approaches are highlighted. Aspects of proper sample preparation before analysis and the selection of adequate strategies for speciation purposes are emphasized.

Inorganic arsenic exposure and neuropsychological development of children of 4-5 years of age living in Spain.

Early-life exposure to inorganic arsenic (iAs) may adversely impact health later in life. To date, evidence of iAs adverse effects on children's neurodevelopment comes mainly from populations highly exposed to contaminated water with conflicting results. Little is known about those effects among populations with low iAs exposure from food intake. We investigated the cross-sectional association between exposure to iAs and neurodevelopment scores among children living in Spain whose main route of exposure was diet. Arsenic species concentrations in urine from 400 children was determined, and the sum of urinary iAs, dimethylarsinic acid, and monomethylarsonic acid was used to estimate iAs exposure. The McCarthy Scales of Children's Abilities was used to assess children's neuropsychological development at about 4-5 years of age. The median (interquartile range) of children's sum of urinary iAs, MMA, and DMA was 4.85 (2.74-7.54) µg/L, and in adjusted linear regression analyses the natural logarithm transformed concentrations showed an inverse association with children's motor functions (ß, [95% confidence interval]; global scores (-2.29, [-3.95, -0.63])), gross scores (-1.92, [-3.52, -0.31]) and fine scores (-1.54, [-3.06, -0.03]). In stratified analyses by sex, negative associations were observed with the scores in the quantitative index (-2.59, [-5.36, 0.17]) and working memory function (-2.56, [-5.36, 0.24]) only in boys. Our study suggests that relatively low iAs exposure may impair children's neuropsychological development and that sex-related differences may be present in susceptibility to iAs related effects; however, our findings should be interpreted with caution given the possibility of residual confounding.

Soil attribute regulates assimilation of roxarsone metabolites by rice (Oryza sativa L.).

Roxarsone (ROX), an organoarsenic feed additive, and its metabolites, can be present in animal manure used to fertilize rice. Rice is prone to absorb arsenic, and is subject to straighthead disorder, which reduces rice yield and is linked with organic arsenic compounds. This study aims to elucidate how soil property affect arsenic accumulation in rice plants fertilized with chicken manure containing ROX metabolites. Manures of chickens fed without or with ROX, designated as control manure and ROX treated manure (ROXCM), respectively, were applied in eight paddy soils of different origins, to investigate the assimilation of arsenic species in rice plants. The results show that inorganic arsenic (arsenate and arsenite), monomethylarsonic acid and dimethylarsinic acid (DMA) were detected in all brown rice and husk, trace tetramethylarsonium and trimethylarsine oxide were occasionally found in these both parts, whereas all these arsenic species were determined in straw, irrespective of manure type. ROXCM application specifically and significantly increased brown rice DMA (P = 0.002), which remarkably enhanced the risk of straighthead disease in rice. Although soil total As impacted grain biomass, soil free-iron oxides and pH dominated arsenic accumulation by rice plants. The significantly increased grain DMA suggests manure bearing ROX metabolites is not suitable to be used in soils with abundant free-iron oxides and/or high pH, if straighthead disorder is to be avoided in rice.

Magnetic metal-organic framework composites for dual-column solid-phase microextraction combined with ICP-MS for speciation of trace levels of arsenic.

A dual column packed with a magnetic metal-organic framework composite (MFC) and mercapto-functionalized MFC nanoparticles (MFC-SH) in microfluidic chip channels is described for array chip-based magnetic solid phase microextraction of arsenic species including arsenite [As(III)], arsenate [As(V)], monomethylarsonous acid (MMA) and dimethylarsinic acid (DMA) in SCC-7 cells. At pH 6, the MFC-SH adsorbs As(III) while MFC quantitatively adsorbs As(V), DMA and MMA. The As(III) adsorbed on the MFC-SH can be desorbed with a 2% solution of thiourea in 0.5 M HNO3. The arsenic species MMA, DMA and As(V) are retained on the MFC but can be desorbed by ammonia. A sequential elution strategy was employed to elute MMA, DMA, As(V) and As(III) one by one for subsequent on-line determination by ICP-MS. The limits of detection are 4.8, 6.3, 3.8 and 7.1 ng L-1 for As(V), DMA, MMA and As(III), respectively. The enrichment factors are between 23 and 25, and the throughput is 7 samples per hour. The arsenic species in (spiked) SCC-7 cell samples were analyzed by the online system with adequate recoveries (89-110%). Graphical abstractSchematic representation of magnetic metal-organic framework composite (MFC) and mercapto-functionalized MFC nanoparticles (MFC-SH) packed dual-column, squamous carcinoma cells (SCC-7), online chip-based array MSPME-ICPMS system. Cell lysis units (blue), Microextraction units (black), Microvalves (green), Outlet (black), Permanent magnets (gray), Intet (red/purple/yellow).

Arsenic species uptake and translocation in Elodea canadensis.

The capacity of Elodea canadensis to phytofiltrate arsenic species from water was evaluated. Plants were adapted to tap water and supplemented with 15 and 250 µg L-1 of As. Inorganic arsenic species (As III, As V), and organic arsenic compounds: monomethylarsonate (MMA) and dimethylarsinate (DMA) were analyzed. Sampling was carried out at different times after exposure in culture water and plant organs. Plants exposed to 15 µg L-1 of As concentration showed no significant difference on As concentration (95% confidence level) in their organs compared to controls. When plants were exposed to 250 µg L-1 of As concentration, a significant increase of As concentration in plant organs was observed. After 1 h exposure, plants reduce 63.16% the As concentration in the culture water, with a bioaccumulation factor (BF) of 4.3. Under these conditions, E. canadensis accumulate As V in roots and do not translocate it to stems (transfer factor <1). MMA was determined in stems and leaves. E. canadensis effectively phytofiltrate As from tap water of a city located in an arsenic endemic area from concentrations of 36 µg L-1 to undetectable levels (10 ng L-1).

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%.

An improved rapid analytical method for the arsenic speciation analysis of marine environmental samples using high-performance liquid chromatography/inductively coupled plasma mass spectrometry.

Arsenic contamination in marine environments is a serious issue because some arsenicals are very toxic, increasing the health risks associated with the consumption of marine products. This study describes the development of an improved rapid method for the quantification of arsenic species, including arsenite (AsIII), arsenate (AsV), arsenocholine (AsC), arsenobetaine (AsB), dimethylarsinic acid (DMA), and monomethyl arsonic acid (MMA), in seaweed, sediment, and seawater samples using high-performance liquid chromatography/inductively coupled plasma-mass spectrometry (HPLC/ICP-MS). ICP-MS based on dynamic reaction cells was used to eliminate spectral interference. Ammonium nitrate- and phosphate-based eluents were used as the mobile phases for HPLC analysis, leading to shorter overall retention time (6 min) and improved peak separation. Arsenicals were extracted with a 1% HNO3 solution that required no clean-up process and exhibited reasonable sensitivity and peak resolution. The optimized method was verified by applying it to hijiki seaweed certified reference material (CRM, NMIJ 7405-a) and to spiked blank samples of sediment and seawater. The proposed method measured the concentration of AsV in the CRM as 9.6 ± 0.6 µg/kg dry weight (dw), which is close to the certified concentration (10.1 ± 0.5 µg/kg dw). The recovery of the six arsenicals was 87-113% for the sediment and 99-101% for the seawater. In the analysis of real samples, AsV was the most abundant arsenical in hijiki and gulfweed, whereas AsB was dominant in other seaweed species. The two inorganic arsenicals (AsIII and AsV) and AsV were the most dominant in the sediment and seawater samples, respectively.