Arsenic Speciation Analysis in Human Saliva

Abstract Background: Determination of arsenic species in saliva is potentially useful for biomonitoring of human exposure and studying arsenic metabolism. Arsenic speciation in saliva has not been reported previously. Methods: We separated arsenic species in saliva using liquid chromatography (LC) and quantified them by inductively coupled plasma mass spectrometry. We further confirmed the identities of arsenic species by LC coupled with electrospray ionization tandem mass spectrometry. These methods were successfully applied to the determination of arsenite (AsIII), arsenate (AsV), and their methylation metabolites, monomethylarsonic acid (MMAV), and dimethylarsinic acid (DMAV), in >300 saliva samples collected from people who were exposed to varying concentrations of arsenic. Results: The mean (range) concentrations (μg/L) in the saliva samples from 32 volunteers exposed to background levels of arsenic were AsIII 0.3 [not detectable (ND) to 0.7], AsV 0.3 (ND to 0.5), MMAV 0.1 (ND to 0.2), and DMAV 0.7 (ND to 2.6). Samples from 301 people exposed to increased concentrations of arsenic in drinking water showed detectable AsIII in 99%, AsV in 98%, MMAV in 80%, and DMAV in 68% of samples. The mean (range) concentrations of arsenic species in these saliva samples were (in μg/L) AsIII 2.8 (0.1–38), AsV 8.1 (0.3–120), MMAV 0.8 (0.1–6.0), and DMAV 0.4 (0.1–3.9). Saliva arsenic correlated with drinking water arsenic. Odds ratios for skin lesions increased with saliva arsenic concentrations. The association between saliva arsenic concentrations and the prevalence of skin lesions was statistically significant (P <0.001). Conclusions: Speciation of AsV, AsIII, MMAV, and DMAV in human saliva is a useful method for monitoring arsenic exposure.

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Speciation of Arsenic in Chicken Meat by Anion-Exchange Liquid Chromatography with Inductively Coupled Plasma-Mass Spectrometry

Journal of AOAC International ◽

10.1093/jaoac/87.1.233 ◽

2004 ◽

Vol 87 (1) ◽

pp. 233-237 ◽

Cited By ~ 12

Author(s):

Aleksandra Polatajko ◽

Joanna Szpunar

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Anion Exchange ◽

Inductively Coupled Plasma ◽

Speciation Analysis ◽

Arsenic Species ◽

Chicken Meat ◽

Dimethylarsinic Acid ◽

Inductively Coupled ◽

Plasma Mass Spectrometry

Abstract A method was developed for speciation analysis of arsenic in chicken meat. Different procedures were optimized for the recovery of arsenic compounds without destroying the original compounds, and 2 anion-exchange liquid chromatography columns were compared for the separation of arsenic species prior to on-line detection by inductively coupled plasma-mass spectrometry. The 2 species found were dimethylarsinic acid (106 ± 5 ng/g) and arsenobetaine (37 ± 4 ng/g). The stability of arsenic species in a chicken meat candidate reference material for at least 12 months was demonstrated.

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Effect of arsenosugar ingestion on urinary arsenic speciation

Clinical Chemistry ◽

10.1093/clinchem/44.3.539 ◽

1998 ◽

Vol 44 (3) ◽

pp. 539-550 ◽

Cited By ~ 106

Author(s):

Mingsheng Ma ◽

X Chris Le

Keyword(s):

Arsenic Speciation ◽

Inorganic Arsenic ◽

Sample Pretreatment ◽

Arsenic Species ◽

Urine Samples ◽

Standard Reference Materials ◽

Dimethylarsinic Acid ◽

Urinary Arsenic ◽

Biomarkers Of Exposure

Abstract We developed and evaluated a method for the determination of μg/L concentrations of individual arsenic species in urine samples. We have mainly studied arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid (MMAA), and dimethylarsinic acid (DMAA) because these are the most commonly used biomarkers of exposure by the general population to inorganic arsenic and because of concerns over these arsenic species on their toxicity and carcinogenicity. We have also detected five unidentified urinary arsenic species resulting from the metabolism of arsenosugars. We combined ion pair liquid chromatography with on-line hydride generation and subsequent atomic fluorescence detection (HPLC/HGAFS). Detection limits, determined as three times the standard deviation of the baseline noise, are 0.8, 1.2, 0.7, and 1.0 μ/L arsenic for arsenite, arsenate, MMAA, and DMAA, respectively. These correspond to 16, 24, 14, and 20 pg of arsenic, respectively, for a 20-μL sample injected for analysis. The excellent detection limit enabled us to determine trace concentrations of arsenic species in urine samples from healthy subjects who did not have excess exposure to arsenic. There was no need for any sample pretreatment step. We used Standard Reference Materials, containing both normal and increased concentrations of arsenic, to validate the method. Interlaboratory studies with independent techniques also confirmed the results obtained with the HPLC/HGAFS method. We demonstrated an application of the method to the determination of arsenic species in urine samples after the ingestion of seaweed by four volunteers. We observed substantial increases of DMAA concentrations in the samples collected from the volunteers after the consumption of seaweed. The increase of urinary DMAA concentration is due to the metabolism of arsenosugars that are present in the seaweed. Our results suggest that the commonly used biomarkers of exposure to inorganic arsenic, based on the measurement of arsenite, arsenate, MMAA, and DMAA, are not reliable when arsenosugars are ingested from the diet.

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Clinimetallomics: Arsenic Speciation in Urine from Patients With Arsenism by HPLC-ICP-MS

Atomic Spectroscopy ◽

10.46770/as.2021.103 ◽

2021 ◽

Vol 42 (5) ◽

Author(s):

Huiling Li

Keyword(s):

Arsenic Speciation ◽

Speciation Analysis ◽

Arsenic Species ◽

The Body ◽

Urine Samples ◽

Clinical Samples ◽

Total Arsenic ◽

Arsenic Poisoning ◽

Icp Ms

Clinimetallomics is proposed as a branch of metallomics that focuses on the study of the metallome in clinical samples of urine, blood, and tissues. As the clinical diagnosis of arsenic poisoning is mainly based on the concentration of total arsenic in urine, the toxicity of arsenic varies greatly in different speciation. Analysis of arsenic speciation with excessive total arsenic in urine can provide a basis for precise treatment. It can also be used to understand the fate of arsenic in the body of patients with arsenic poisoning after treatment with sodium dimercaptopropane sulfonate. In this study, a HPLC-ICP-MS method was established for the determination of arsenic species in urine samples from patients diagnosed with arsenism. Use the established method to detect urine samples, which can be directly assayed after simple sample dilution with 20 mmol/L EDTA-2Na. With the concentration of arsenic speciation in the range of 1.0~100.0 ng/mL, the linear correlation coefficient was higher than 0.99996. The recoveries were between 92.4% and 109.0%. The precision of the concentration and retention time (n = 3) were less than 3.0% and 0.3%, respectively, and the detection limit was between 1.42 ng/mL and 1.86 ng/mL. This method can be applied to arsenic speciation in the urine of healthy people, in patients treated for arsenic poisoning, and in patients diagnosed with arsenism.

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Mapping of arsenic species and identification of a novel arsenosugar in giant clams Tridacna maxima and Tridacna derasa using advanced mass spectrometric techniques

Environmental Chemistry ◽

10.1071/en07009 ◽

2007 ◽

Vol 4 (3) ◽

pp. 187 ◽

Cited By ~ 17

Author(s):

Volker Nischwitz ◽

Spiros A. Pergantis

Keyword(s):

Mass Spectrometry ◽

Arsenic Speciation ◽

Speciation Analysis ◽

Arsenic Species ◽

Marine Organisms ◽

Selected Reaction Monitoring ◽

Detailed Knowledge ◽

Giant Clam ◽

Arsenic Metabolism ◽

Giant Clams

Environmental context. Arsenic is known to accumulate in various marine organisms. The high acute toxicity of inorganic arsenic species and the potential chronic toxicity of some organoarsenic species require detailed knowledge about the occurrence and metabolism of arsenic compounds in marine organisms. The application of advanced analytical techniques still allows, even after decades of arsenic speciation, the identification of novel species. In addition, comprehensive mapping of all arsenic species present in marine organisms may allow for a more detailed understanding of arsenic metabolism. Abstract. Because of their symbiotic microalgae, giant clams (Tridacna species) exhibit a unique arsenic metabolism, which has been shown in previous studies to involve a large number of arsenic species. This study demonstrates the application of liquid chromatography (HPLC) online with electrospray tandem mass spectrometry (ES-MS/MS) as well as inductively coupled plasma mass spectrometry (ICP-MS) for arsenic speciation analysis in giant clam extracts. Selected reaction monitoring (SRM) was used for sensitive and selective detection of a large number of arsenic species in a single chromatographic run. Novel aspects are the analysis of 10 tissue fractions from one clam and the analysis of kidney extracts both from T. maxima and T. derasa with the same method thus offering the possibility for direct comparisons. Moreover, HPLC-ES-MS/MS in the precursor ion scan mode and product ion scan mode allowed the identification of a novel sulfonated dimethylarsenosugar and the partial characterisation of another unknown arsenic species. The results indicate that most arsenic species are accumulated in the kidneys. However, arsenobetaine was found at similar contents in all analysed tissue fractions of one T. maxima clam.

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Sample Preparation and Storage Can Change Arsenic Speciation in Human Urine

Clinical Chemistry ◽

10.1093/clinchem/45.11.1988 ◽

1999 ◽

Vol 45 (11) ◽

pp. 1988-1997 ◽

Cited By ~ 75

Author(s):

Jörg Feldmann ◽

Vivian W-M Lai ◽

William R Cullen ◽

Mingsheng Ma ◽

Xiufen Lu ◽

...

Keyword(s):

Human Urine ◽

Arsenic Speciation ◽

Speciation Analysis ◽

Arsenic Species ◽

Urine Samples ◽

Dimethylarsinic Acid ◽

Detection Techniques ◽

Monomethylarsonic Acid ◽

The Stability ◽

And Storage

Abstract Background: Stability of chemical speciation during sample handling and storage is a prerequisite to obtaining reliable results of trace element speciation analysis. There is no comprehensive information on the stability of common arsenic species, such as inorganic arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid, dimethylarsinic acid, and arsenobetaine, in human urine. Methods: We compared the effects of the following storage conditions on the stability of these arsenic species: temperature (25, 4, and −20 °C), storage time (1, 2, 4, and 8 months), and the use of additives (HCl, sodium azide, benzoic acid, benzyltrimethylammonium chloride, and cetylpyridinium chloride). HPLC with both inductively coupled plasma mass spectrometry and hydride generation atomic fluorescence detection techniques were used for the speciation of arsenic. Results: We found that all five of the arsenic species were stable for up to 2 months when urine samples were stored at 4 and −20 °C without any additives. For longer period of storage (4 and 8 months), the stability of arsenic species was dependent on urine matrices. Whereas the arsenic speciation in some urine samples was stable for the entire 8 months at both 4 and −20 °C, other urine samples stored under identical conditions showed substantial changes in the concentration of As(III), As(V), monomethylarsonic acid, and dimethylarsinic acid. The use of additives did not improve the stability of arsenic speciation in urine. The addition of 0.1 mol/L HCl (final concentration) to urine samples produced relative changes in inorganic As(III) and As(V) concentrations. Conclusions: Low temperature (4 and −20 °C) conditions are suitable for the storage of urine samples for up to 2 months. Untreated samples maintain their concentration of arsenic species, and additives have no particular benefit. Strong acidification is not appropriate for speciation analysis.

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Monitoring Arsenic Species Content in Seaweeds Produced off the Southern Coast of Korea and Its Risk Assessment

Environments ◽

10.3390/environments7090068 ◽

2020 ◽

Vol 7 (9) ◽

pp. 68

Author(s):

Min-hyuk Kim ◽

Junseob Kim ◽

Chang-Hyun Noh ◽

Seogyeong Choi ◽

Yong-Sung Joo ◽

...

Keyword(s):

Risk Assessment ◽

South Korea ◽

Arsenic Speciation ◽

Arsenic Exposure ◽

Inorganic Arsenic ◽

Speciation Analysis ◽

Arsenic Species ◽

Dimethylarsinic Acid ◽

Concentration Data ◽

Seaweed Species

Seaweed, a popular seafood in South Korea, has abundant dietary fiber and minerals. The toxicity of arsenic compounds is known to be related to their chemical speciation, and inorganic arsenic (iAs) is more detrimental than other species. Due to the different toxicities of the various chemical forms, speciation analysis is important for evaluating arsenic exposure. In this study, total arsenic (tAs) and six arsenic species (arsenite, arsenate, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine, and arsenocholine) were analyzed in 180 seaweed samples. Although there were differences between seaweed species, the concentration of tAs was detected at levels ranging from 1 to 100 µg/g, and the distribution of six arsenic species differed depending on the seaweed species. No correlation between the concentration of iAs and tAs was found in most seaweed species. Through statistical clustering, hijiki and gulfweed were seen to be the seaweeds with the highest ratios of iAs to tAs. Using the iAs concentration data from the arsenic speciation analysis, a risk assessment of seaweed intake in South Korea was conducted. The margin of exposure values showed no meaningful risk for the general population, but low levels of risk were identified for seaweed consumers, with high intakes of gulfweed and hijiki.

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