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1.
Food Chem ; 338: 128028, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091983

RESUMO

Direct determination of arsenic species in real samples is challenging due to their trace concentration and spectral interferences by coexisting ions. Herein, we proposed an ultrasound-assisted dispersive solid phase microextraction (DSPME) procedure for the analyses of the trace inorganic arsenic. The hydrothermally synthesized cadmium sulfide nanoparticles (CdS NPs) completely adsorbed both arsenic species within 20 s at the initial arsenic concentration of 100 µg L-1. The detection limit (3 S/m) of the proposed method was found to be 0.5 ± 0.2 and 0.8 ± 0.2 ng L-1 for As(III) and As(V), respectively. The accuracy of the method against the systematic and constant errors was confirmed by the analysis of the Standard Reference Material (SRM) (>95% recovery with <5% RSD). The Student's t-test values were found to be less than the critical Student's t value at a 95% confidence level. The method was successfully employed for the determination of arsenic in food samples.


Assuntos
Arsenicais/análise , Análise de Alimentos , Nanopartículas/química , Espectrofotometria/métodos , Adsorção , Arsenicais/isolamento & purificação , Compostos de Cádmio/química , Humanos , Concentração de Íons de Hidrogênio , Microextração em Fase Sólida , Sonicação , Sulfetos/química
2.
Food Chem ; 338: 127842, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32822902

RESUMO

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.


Assuntos
Arsenicais/química , Ácido Cacodílico/química , Cádmio/química , Contaminação de Alimentos/análise , Oryza/química , Arsenicais/análise , Ácido Cacodílico/análise , Cádmio/análise , Carbonato de Cálcio/química , Ácido Cítrico/química , Culinária/métodos , Concentração de Íons de Hidrogênio , Espectrometria de Massas/métodos , Oryza/metabolismo
3.
Aquat Toxicol ; 230: 105693, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33310671

RESUMO

Sea dumping of chemical warfare (CW) took place worldwide during the 20th century. Submerged CW included metal bombs and casings that have been exposed for 50-100 years of corrosion and are now known to be leaking. Therefore, the arsenic-based chemical warfare agents (CWAs), pose a potential threat to the marine ecosystems. The aim of this research was to support a need for real-data measurements for accurate risk assessments and categorization of threats originating from submerged CWAs. This has been achieved by providing a broad insight into arsenic-based CWAs acute toxicity in aquatic ecosystems. Standard tests were performed to provide a solid foundation for acute aquatic toxicity threshold estimations of CWA: Lewisite, Adamsite, Clark I, phenyldichloroarsine (PDCA), CWA-related compounds: TPA, arsenic trichloride and four arsenic-based CWA degradation products. Despite their low solubility, during the 48 h exposure, all CWA caused highly negative effects on Daphnia magna. PDCA was very toxic with 48 h D. magna LC50 at 0.36 µg × L-1 and Lewisite with EC50 at 3.2 µg × L-1. Concentrations at which no immobilization effects were observed were slightly above the analytical Limits of Detection (LOD) and Quantification (LOQ). More water-soluble CWA degradation products showed no effects at concentrations up to 100 mg × L-1.


Assuntos
Arsênico/toxicidade , Substâncias para a Guerra Química/toxicidade , Daphnia/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Arsênico/análise , Arsenicais/análise , Substâncias para a Guerra Química/análise , Cloretos/análise , Ecossistema , Dose Letal Mediana , Limite de Detecção , Água do Mar/química , Testes de Toxicidade Aguda , Poluentes Químicos da Água/análise
4.
Shokuhin Eiseigaku Zasshi ; 61(3): 86-94, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32611948

RESUMO

Most fish contain some kinds of organoarsenic compounds. To assess the health risk for the chronic effects due to intake of these compounds, it is necessary to quantify the concentration of each chemical form, since the toxicity is difference depending on the form. We developed and validated the LC-MS/MS method to determine the concentration of monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), trimethylarsine oxide (TMAO), tetramethylarsonium (TeMA), arsenobetaine (AB), and arsenocholine (AC) in fish. Using this method, we quantified the concentration of each organoarsenic compounds and total arsenic in 50 fish samples from across 10 groups. Total arsenic concentration ranged from 0.53 to 25 mg/kg in all samples, except for in thread-sail filefish where the concentration ranged from 8.3 to 25 mg/kg. With the exception of sardines, in all samples AB was found at the highest level in relation to the total arsenic concentration. In sardines, the concentration of DMA was higher than that of AB, accounting for 16 to 24% of total arsenic. In red sea bream, concentrations of total arsenic, AB, and AC in farm-raised fish were lower than those in wild-caught fish.


Assuntos
Arsênico , Arsenicais , Peixes , Animais , Arsênico/análise , Arsenicais/análise , Cromatografia Líquida , Alimentos Marinhos/análise , Espectrometria de Massas em Tandem
5.
Artigo em Inglês | MEDLINE | ID: mdl-32365627

RESUMO

Background: Arsenic is a toxic metalloid element widely distributed throughout the environment. Arsenic contaminated water has become an ongoing public health issue affecting hundred million people worldwide. The aim of this paper was to summarize the evidence in the association between arsenic metabolites and urinary tract cancer risk. Methods: A systematic review was conducted searching for observational studies that evaluated the association of arsenic metabolites and urinary tract cancer. Risk estimates from individual studies were pooled by using random effects models. Results: All the metabolites considered in this study resulted to be significantly associated to urothelial cancer, respectively: IA% 3.51 (1.21-5.82) (p = 0.003), MMA with WMD = 2.77 (1.67-3.87) (p < 0.001) and DMA with WMD = -4.56 (-7.91-1.22) (p = 0.008). Conclusions: Arsenic metabolites are significantly associated to urothelial cancer. Future studies will help to verify the independent association(s) between arsenic metabolites and urothelial cancer.


Assuntos
Arsênico , Arsenicais , Carcinoma de Células de Transição , Neoplasias Urológicas , Arsênico/análise , Arsênico/toxicidade , Arsenicais/análise , Carcinoma de Células de Transição/induzido quimicamente , Carcinoma de Células de Transição/epidemiologia , Exposição Ambiental/efeitos adversos , Humanos , Estudos Observacionais como Assunto , Neoplasias Urológicas/induzido quimicamente , Neoplasias Urológicas/epidemiologia
6.
Sci Total Environ ; 731: 138840, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32417471

RESUMO

The health effects of drinking water exposure to inorganic arsenic are well known but are less well defined for dietary exposure. The rising concerns of arsenic risks from diet motivated this study of arsenic concentrations in highland barley, vegetables, meat, and dairy products to evaluate arsenic exposure source and to assess health risks among rural residents of Ngari area, western Tibet. Total arsenic and arsenic speciation were measured by inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography combined with ICP-MS (HPLC-ICP-MS) respectively. Average total arsenic concentrations of 0.18 ± 0.21 (n = 45, median: 0.07 mg·kg-1), 0.40 ± 0.57 (n = 17, median: 0.15 mg·kg-1), 0.21 ± 0.16 (n = 12, median: 0.17 mg·kg-1), and 0.18 ± 0.08 (n = 11, median: 0.22 mg·kg-1) were observed in highland barley, vegetables, meat, and dairy products, respectively. Inorganic arsenic was determined to be the main species of arsenic in highland barley, accounting for about 64.4 to 99.3% (average 83.3%) of total arsenic. Nearly half (44.4%) of the local residents had ingested >3.0 × 10-4 mg·kg-1·d-1 daily dose of arsenic from highland barley alone, above the maximum oral reference dose recommended by the United States Environmental Protection Agency (USEPA). The inorganic arsenic daily intake from highland barley was 3.6 × 10-4 mg·kg-1·d-1. Dietary exposure to inorganic arsenic alone increased the cancer risk probability to 5.4 in 10,000, assuming that the inorganic arsenic in highland barley has the same carcinogenic effects as that in water.


Assuntos
Arsênico/análise , Arsenicais/análise , Cromatografia Líquida de Alta Pressão , Exposição Dietética , Contaminação de Alimentos/análise , Humanos , Tibet , Verduras
7.
Arch Environ Contam Toxicol ; 79(1): 60-79, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32285162

RESUMO

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.


Assuntos
Arsenicais/análise , Bioacumulação , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Plantas/efeitos dos fármacos , Rios/química , Poluentes Químicos da Água/análise , Arsenicais/metabolismo , Ácido Cacodílico/análise , Ácido Cacodílico/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Ecossistema , Galium/efeitos dos fármacos , Galium/crescimento & desenvolvimento , Galium/metabolismo , Espectrometria de Massas/métodos , Plantas/metabolismo , Polônia , Urtica dioica/efeitos dos fármacos , Urtica dioica/crescimento & desenvolvimento , Urtica dioica/metabolismo , Poluentes Químicos da Água/toxicidade
8.
Anal Sci ; 36(2): 233-239, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32037373

RESUMO

An inter-laboratory study was carried out to characterize a candidate hijiki seaweed for its concentrations of total arsenic and water-soluble arsenic compounds, particularly arsenosugar compounds. The candidate material, a dried hijiki seaweed powder, was analyzed by individual techniques in two laboratories. The water-soluble arsenic compounds were separated by anion exchange, and reversed-phase columns, and As(V), DMA and four kinds of arsenosugars, namely glycerol (-OH), phosphate (-PO4), sulfonate (-SO3), and sulfate (-SO4) types were detected by HPLC-ICP-MS. The methods applied were validated by analyzing a second sample, the NMIJ CRM 7405-a hijiki seaweed, which is certified for both total arsenic and As(V). Techniques for the inter-laboratory study, extraction efficiencies under different extraction conditions, some chromatographic techniques and sequential extraction were investigated. The results from the two laboratories for the candidate hijiki material showed good agreement within the measurement uncertainties for total and water-soluble arsenic compounds.


Assuntos
Arsenicais/análise , Padrões de Referência , Alga Marinha/química , Açúcares/química , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Espectrometria de Massas/métodos , Solubilidade
9.
Chemosphere ; 248: 126084, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32059333

RESUMO

Temperature, light intensity (LI), adsorbent source and concentrations are key external factors affecting algal metabolism and thus metal-accumulation mechanisms. In this study, the alga Sarcodia suiae was exposed individually to a range of temperature (15, 20, and 25 °C), and LI (30, 55, and 80 µmol photons m-2 s-1) at initial arsenate [As(V)] concentration (iconc: 0, 62.5, 125, 250, and 500 µg L-1) conditions, to investigate the variations of total arsenic (TAs) and inorganic arsenic (iAs) accumulation mechanisms in the algal body. Temperature significantly affected TAs and arsenite [As(III)] production and maximum absorption were obtained at 15 °C, which was significantly stimulated by increasing iconc. However, the temperature did not affect As(V) production. LI had no significant effect on TAs or iAs production, although maximum absorption was estimated in 80 µmol photons m-2 s-1. The iAs component of TAs was much greater in the temperature experiment particularly under 250-500 µg L-1iconc than in the LI experiment, is witnessed. Overall, temperature and iconc strongly affected As accumulation. The predominant iAs produced was As(III), regardless of temperature or LI, suggesting that the alga favored As(III) biosorption. Also, visible effects on the morphology of this alga were adverse with increased concentration and environmental factors did affect the difference somewhat. Our results contribute to improving our understanding of the effects of the tested factors on As cycling, which is necessary for maximizing biosorption of algae if utilized for bioremediation studies as well as in the wastewater treatment implementation approach in the environment.


Assuntos
Arsênico/análise , Arsenicais/análise , Rodófitas/metabolismo , Poluentes Químicos da Água/análise , Arsênico/metabolismo , Arsenicais/metabolismo , Biodegradação Ambiental , Modelos Teóricos , Taiwan , Temperatura , Poluentes Químicos da Água/metabolismo
10.
Ecotoxicol Environ Saf ; 193: 110334, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32088552

RESUMO

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.


Assuntos
Arsênico/toxicidade , Gastrópodes/química , Rios/química , Poluentes Químicos da Água/toxicidade , Animais , Arseniatos/análise , Arsênico/análise , Arsenicais/análise , Arsenitos/análise , Ácido Cacodílico/análise , Humanos , Modelos Biológicos , Medição de Risco , Poluentes Químicos da Água/análise
11.
Environ Geochem Health ; 42(9): 2723-2732, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31897873

RESUMO

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.


Assuntos
Arsênico/análise , Arsenicais/análise , Coriolaceae/química , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Arseniatos/análise , Arsenitos/análise , Ácido Cacodílico/análise , Cromatografia Líquida de Alta Pressão/métodos , Carpóforos/química , Espectrometria de Massas/métodos , Mineração , Quebeque , Reino Unido
12.
J Agric Food Chem ; 68(4): 943-960, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31913614

RESUMO

Diet, especially seafood, is the main source of arsenic exposure for humans. The total arsenic content of a diet offers inadequate information for assessment of the toxicological consequences of arsenic intake, which has impeded progress in the establishment of regulatory limits for arsenic in food. Toxicity assessments are mainly based on inorganic arsenic, a well-characterized carcinogen, and arsenobetaine, the main organoarsenical in seafood. Scarcity of toxicity data for organoarsenicals, and the predominance of arsenobetaine as an organic arsenic species in seafood, has led to the assumption of their nontoxicity. Recent toxicokinetic studies show that some organoarsenicals are bioaccessible and cytotoxic with demonstrated toxicities like that of pernicious trivalent inorganic arsenic, underpinning the need for speciation analysis. The need to investigate and compare the bioavailability, metabolic transformation, and elimination from the body of organoarsenicals to the well-established physiological consequences of inorganic arsenic and arsenobetaine exposure is apparent. This review provides an overview of the occurrence and assessment of human exposure to arsenic toxicity associated with the consumption of seafood.


Assuntos
Arsenicais/análise , Exposição Dietética/efeitos adversos , Contaminação de Alimentos/análise , Alimentos Marinhos/análise , Animais , Arsenicais/metabolismo , Exposição Dietética/análise , Humanos , Medição de Risco
13.
Artigo em Inglês | MEDLINE | ID: mdl-31936289

RESUMO

Rice-based products are widely used to feed infants and young children. However, the association of rice-based products and high arsenic (As) concentrations have been investigated in a number of studies, but there is limited information from Australia. Therefore, the purpose of this study was to determine the As concentration and dietary exposure in infant rice milk, cereal, crackers and pasta as well as to investigate the relationship between As concentration and rice content, rice type and product origin. Total arsenic (tAs) concentrations were determined by nitric acid digestion and ICP-MS while inorganic arsenic (iAs) was determined by acid extraction, followed by ICP-MS with an interfaced hydride generation system. Nearly 75% of samples had inorganic As exceeding the EU maximum levels for infants and children (0.1 mg kg-1) and the mean iAs percentage of total reached as high as 84.8%. High tAs concentration was positively correlated with rice content and also related to brown (wholegrain). Estimates of dietary exposure showed that infants consuming large amounts of rice pasta or crackers will have an increased risk of health impact associated with excess intake of As through dietary exposure. Moreover, the current Australian guidelines for As in rice (1 mg kg-1) are above the WHO or EU guideline and therefore, will be less protective of high sensitivity consumers like infants and children.


Assuntos
Arsênico/análise , Exposição Dietética/estatística & dados numéricos , Contaminação de Alimentos/estatística & dados numéricos , Inocuidade dos Alimentos , Alimentos Infantis/estatística & dados numéricos , Oryza/química , Arsenicais/análise , Austrália , Pré-Escolar , Grão Comestível/química , Contaminação de Alimentos/análise , Humanos , Lactente , Alimentos Infantis/normas
14.
Food Addit Contam Part B Surveill ; 13(1): 25-33, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31690242

RESUMO

The aim of this study was to evaluate the health risk of arsenic exposure by consumption of rice and its products marketed in northwestern Mexico. Sixty-six national and imported rice products were purchased in markets in northwestern Mexico, an endemic arsenic region. Total and inorganic arsenic in rice samples were analysed by inductively coupled plasma atomic emission spectroscopy and the risk assessment was evaluated according to the hazard quotient (HQ) and carcinogenic risk (CR). Total and inorganic arsenic in rice samples ranged from 0.06 to 0.29 mg/kg and from 0.03 to 0.13 mg/kg, respectively, and 40% of the analysed samples exceeded FAO/WHO arsenic recommended levels. The inorganic/total arsenic ratio ranged from 15% to 65%. The HQ and CR values for total and inorganic arsenic did not exceed safety levels. Therefore, rice supply in the northwestern of Mexico appears to be safe for human consumption.


Assuntos
Arsênico/análise , Arsenicais/análise , Carcinógenos/análise , Contaminação de Alimentos/análise , Oryza/química , Exposição Dietética , Humanos , México , Medição de Risco , Espectrofotometria Atômica
15.
Chemosphere ; 241: 124956, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31605996

RESUMO

High contents of arsenic were detected in soils in Guandu plain, northwest Taiwan. To determine the sources and speciation of As in the soils, the depth profiles of soil properties, elemental composition and As speciation were investigated. The As concentrations in the soil profile ranged from 152 to 1222 mg kg-1, with the highest concentration at the depth of 70-80 cm. The As distribution was found to be positively correlated to Fe, Pb, and Ba. The As(V)-adsorbed ferrihydrite and scorodite were the predominant phases in the top layers (<50 cm), while beudantite was the predominant phase below 50 cm along with As(III)- and As(V)-adsorbed ferrihydrite as the minor components. The results of sequential extraction showed that As-associated with noncrystalline and crystalline Fe/Al hydrous oxides and residual phases were predominant at the depths of 0-60, 60-100 and 100-140 cm, respectively, indicating an increasing As recalcitrance with soil depth. Based on the soil properties, and elemental and mineral compositions at different soil depths, the origin of beudantite in the soils was likely allogenic rather than authigenic or anthropogenic. The formation of scorodite in the surface soils was suggested to be transformed from beudantite. As-associated Fe hydrous oxides may be contributed by the progressive dissolution of beudantite and scorodite, and the continuous influxes of As and Fe. While Fe hydrous oxides were able to immobilize As during the dissolution of As-bearing minerals, the increase of As mobility in soils may imply an increase in the environmental risk of As over time.


Assuntos
Arsênico/análise , Poluentes do Solo/análise , Solo/química , Arsênico/química , Arsênico/normas , Arsenicais/análise , Compostos Férricos/análise , Minerais/análise , Taiwan , Espectroscopia por Absorção de Raios X
16.
Anal Bioanal Chem ; 411(27): 7251-7260, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31612256

RESUMO

Chloride widely exists in the environment and will cause serious interference for arsenic speciation analysis. The determination of four arsenic species including arsenite (As(III)), arsenate (As(V)), monomethylarsenate (MMA), and dimethylarsonate (DMA) in samples containing high concentrations of Cl- was carried out in this work by coupling of liquid chromatography (LC) with hydride generation atomic fluorescence spectrometry (HG-AFS). The interference of Cl- was successfully eliminated by coupling two anion-exchange chromatographic columns in series and eluting with 35.0 mmol L-1 (NH4)2HPO4 (pH = 6.00). A novel pre-treatment system was subsequently developed to realize on-line column switch and pre-reduction of As(V). The analysis time was shortened by an isocratic elution but programmed flow rate method, and the sensitivity of As(V) was also enhanced by the introduction of pre-reduction using the developed system. The proposed method can resist at least 10 g L-1 Cl- without any pre-treatment operations. Since LC-HG-AFS is low-cost and can be afforded or self-assembled by most labs, the developed method can be adopted as a routine analysis method for arsenic species in chloride-bearing samples, such as urine and seawater. Graphical abstract.


Assuntos
Arseniatos/análise , Arsenicais/análise , Arsenitos/análise , Poluentes Químicos da Água/análise , Arseniatos/urina , Arsênico/análise , Arsênico/urina , Arsenicais/urina , Arsenitos/urina , Cloretos/análise , Cloretos/urina , Cromatografia Líquida de Alta Pressão/instrumentação , Desenho de Equipamento , Humanos , Limite de Detecção , Metilação , Água do Mar/análise , Espectrometria de Fluorescência/instrumentação , Espectrofotometria Atômica/instrumentação , Poluentes Químicos da Água/urina
17.
Environ Monit Assess ; 191(11): 674, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31654271

RESUMO

The rice consumption behaviors of Thai citizens vary among regions. However, the influence of different consumption patterns on arsenic (As) exposure has never been reported. This study was conducted to investigate the effects of rice consumption behavior on As exposure levels. White rice (n = 96) and sticky rice (n = 63) samples were collected from local households in northern Thailand. The actual rice consumption behavior (type, frequency, and amount of rice consumed) was surveyed from the households where the rice samples were collected and used to calculate individual As exposures. The white rice (2.1%) and sticky rice (6.3%) samples contained inorganic As at higher concentrations than the Codex standard (0.2 mg kg-1). Approximately 58.3% of participants consumed white rice for breakfast and sticky rice for lunch and dinner, while 41.8% of participants consumed only white rice or sticky rice daily. Wide variations of As exposure (1 × 10-4 to 2 × 10-3 mg kg-1 day-1) were found. The average As exposure from only sticky rice consumption and combined rice consumption was 2 times higher than the As exposure from only white rice consumption. The rice ingestion rate was the most important factor affecting the level of As exposure resulting from the white rice-only and combined rice consumption patterns. For the combined rice consumption pattern, 45.7 to 93.5% of the total As exposure was from sticky rice consumption. Regarding individual characteristics, older and lower weight participants tended to consume lower amounts of rice. Thus, lower As exposure and fewer health impacts were found in those participants.


Assuntos
Arsênico/análise , Arsênico/toxicidade , Arsenicais/análise , Contaminação de Alimentos/análise , Oryza/química , Medição de Risco/estatística & dados numéricos , Adulto , Idoso , Dieta , Monitoramento Ambiental , Características da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tailândia
18.
Anal Chem ; 91(21): 13810-13817, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31559825

RESUMO

A frontal chromatography-ICP-MS method (FC-ICP-MS) is proposed as an innovative approach for fast elemental speciation analysis: inorganic arsenic speciation was selected as the first case study to prove the feasibility of the technique and to explore its potentialities and limits. The principal benefits of the FC-ICP-MS approach are the short analysis time and the very simple instrumental setup. As(III) and As(V) front separation is performed over a strong anion exchanger at pH 7.5. After the optimization of the instrumental setup and the frontal chromatographic parameters, As(III) and As(V) concentrations up to 240 µg/kg can be determined within 120-140 s using different univariate and multivariate calibration approaches. Best results in terms of accuracy in prediction were obtained using the partial least squares (PLS) calibration achieving limits of detection of 0.18 and 0.21 µg/kg for As(III) and As(V), respectively. This approach was also used to establish the figures of merit of the method. The proved feasibility and good performances (in terms of analysis time and accuracy) of this technique lay the groundwork for future applications of FC-ICP-MS for the speciation of other elements.


Assuntos
Arsênico/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Arsênico/química , Arsenicais/análise , Arsenicais/química , Calibragem , Cromatografia por Troca Iônica , Resinas de Troca Iônica , Limite de Detecção , Fatores de Tempo
19.
Environ Sci Pollut Res Int ; 26(29): 29896-29907, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31407267

RESUMO

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 .


Assuntos
Arseniatos/análise , Arsenicais/análise , Arsenitos/análise , Monitoramento Biológico/métodos , Líquens/química , Monitoramento Biológico/instrumentação , Ácido Cacodílico/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , África do Sul , Urbanização
20.
Food Addit Contam Part B Surveill ; 12(4): 275-279, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31409256

RESUMO

A total of 200 rice and rice products from New Zealand and Australia were purchased from retail outlets during 2017 for inorganic arsenic analysis by ICP-MS. The survey of foods placed a particular emphasis on products marketed specifically for infants and young. A total of 159 samples (80%) gave positive results for inorganic arsenic, with a mean concentration of 0.06 mg/kg and a range of <0.01-0.14 mg/kg. Two products marketed for infants and young children age-cohort had the highest concentrations of inorganic arsenic. Both exceeded the EU maximum level for rice destined for the production of food for infants and young children of 0.1 mg/kg. The mean concentration of inorganic arsenic for only raw rice samples was 0.07 mg/kg, with a range of <0.02-0.12 mg/kg. In general, the concentration of inorganic arsenic in rice and rice products from New Zealand and Australia was low compared to concentrations reported from comparable studies overseas.


Assuntos
Arsenicais/química , Análise de Alimentos , Contaminação de Alimentos , Oryza/química , Arsenicais/análise , Austrália , Inocuidade dos Alimentos , Humanos , Lactente , Alimentos Infantis , Nova Zelândia
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