Overview
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Key numbers
The worker extracted the full PDF text with layout preservation twice and compared extraction hashes before commit. The following lines are copied from numeric/table-bearing regions of the PDF and retain the source units and wording where legible:
- current maximum contaminant level of 10 µg/l (World Health
- drinking water at levels ranging from 1 µg/l (parts per billion, ppb)
- Organization 2022). Inorganic forms of arsenic (arsenite, iAsIII to >100 mg/l (parts per million) (Lu et al. 2014b; Barai et al. 2017;
- advantage is that it requires customized adaptation to detectors a control 20 g/l pepsin solution with 0.5% HCl (trace metal grade,
- arsenic species. HPLC-ICPMS has proven to be more broadly used solutions at a final concentration of 5 µg/l and incubated over
- Filter-sterilized stock solutions (10 g/l) were made for AsB (95% beads), B (silica spheres), and E (ceramic and silica spheres and
- (iAsIII, 99.995% trace metals basis, Sigma-Aldrich, St. Louis, California, United States), and PowerBead Pro (ceramic spheres)
- Missouri), sodium arsenate dibasic heptahydrate (iAsV, ≥98% was obtained from Qiagen (Hilden, Germany). To evaluate the
- (MMAV, 95%, Wako Chemicals, Richmond, Virginia), and caco of ultrapure water were added to each lysing matrix tube and
- dylic acid (DMAV, 99%, Sigma-Aldrich, St. Louis, Missouri). then beaten for 1 min using the mini-BeadBeater 24 (BioSpec
- made with HPLC-grade ammonium phosphate dibasic (Sigma- extraction method 3050B without reflux). Briefly, 200 µl of 50%
- Aldrich, St. Louis, Missouri), and pH was adjusted using trace nitric acid and 500 µl of 20% hydrochloric acid were added to
- taining 10 µg/l of each arsenic standard (AsB, iAsIII, iAsV, MMAV, (liver and/or bladder) were collected post-euthanasia. For fasting
- was collected. Liver tissue from this mouse was compared with acid and 5% methanol (v/v), adjusted to pH 5.95 with tetrabuty
- the same tissue from another C57BL/6J mouse exposed to 10 mg/l lammonium hydroxide. Standard solutions containing 0, 1, 2, 5,
- iAsIII in drinking water ad libitum for 12 h prior. For tissue macer 10, 20, and 50 µg/l of iAsIII, iAsV, MMAV, and DMAV were freshly
- body weight via oral gavage and euthanized after 24 h. For the assays, standard solutions containing 0, 1, 2, 5, 10, and 20 µg/l of
- sary. AsB in the samples was quantified using Clarity software standards (5 µg/l final concentration) and incubated overnight
- Both labs evaluated Standard Reference Material 2669 (Fig. 1B) and when plotted and tested against a theoretical 100%
- (Arsenic Species in Frozen Human Urine) obtained from the recovery, papain incubation increased iAsIII by 31% and decreased
- National Institute of Standards and Technology (NIST). This AsB, MMAV, and iAsV by 2%, 46% and 81%, respectively (median
- material consisted of 2 vials containing different levels of 7 percentages) (Fig. 1C). Pepsin incubation was closer to 100% for all
- arsenic species (AsB, arsenocholine, iAsIII, iAsV, DMAV, MMAV, species, but still increased iAsIII by 14% and decreased AsB, MMAV,
- and trimethylarsine oxide). Only AsB, iAsIII, iAsV, DMAV, and and iAsV by 5%, 3%, and 9%, respectively (Fig. 1D).
- (Version 9.4.1, La Jolla, California). Parametric statistics were in magnitude from relatively minor for AsB (6% decrease), MMAV
- used when normality was supported by either the D’Agostino (5% increase), and iAsV (4% decrease) to larger differences
- and Pearson test or the Kolmogorov–Smirnov test. For 2-way observed for iAsIII (increased by 16%) and DMAV (decreased by
- ANOVAs, data were entered with treatments in columns and 12%). These results suggest that the impact of pepsin digestion
- digests of liver samples from a mouse exposed to 10 mg/l iAsIII ad
- positive rate) was set to 10%, and q-values <0.05 were considered papain product is a crude plant extract, we conducted a proteo
- (Pearson’s r) or non-normal (Spearman’s r) variables, and simple enzymes (Table 1). Notably, glyceraldehyde-3-phosphate dehy
- linear (least squares) regression was used to fit a straight line to drogenase was identified (100% probability), which has been
- multiple comparisons). Recovery efficiencies of papain (C) and pepsin (D) tested against the theoretical threshold of 100% (1-sample Wilcoxon test).
- Table 1. Proteins identified in the commercial papain protease product.
- of DMAV and MMAV and only a slight decrease (3%) of AsB and lower levels of all species in the liver from the exposed
- beating with a 16% decreased recovery of iAsIII and 17% increased washing the matrix beads reduces background levels of all
- following controlled exposure to iAsIII (B; 2-way ANOVA of log-transformed data with Tukey’s adjustment). Each bar represents the mean value of
- replicate liver samples from the same mouse (technical replicates of the same liver), error bars represent 95% CI of the mean, and dots represent
- control of iAsIII dosing in these animals, these results suggest increased to 0.93, whereas the width of the 95% CI around the
- that factors other than exposure dose impact arsenic body bur coefficient decreased by 32%. Overall, these results provide
- 12-h exposure, ensuring a range of arsenic levels was observed. able diet used for germ-free mouse husbandry (Fig. 5A). In con
- body weight via oral gavage, and male–female pairs were ran tectable or trace amounts (<2.0 ng per g sample) of iAsIII.
Methods (brief)
- liquid chromatography (HPLC)–inductively coupled plasma mass spectrometry (ICPMS). Enzyme-assisted digestion by papain vs.
- fasted vs. unfasted mice, and conventional vs. germ-free mice. Finally, between-lab differences in HPLC-ICPMS instrumentation/
- arsenic species levels. Our results provide a benchmark for evaluating arsenic species in murine models, including adequate sample
- Keywords: arsenic; speciation; HPLC-ICPMS; mouse models; risk assessment; diet; microbiome; inter-individual variability
- with skin, bladder, lung, and liver cancer (Faita et al. 2013; Hong ples collected/processed, and what arsenic species were
- sample size needed to conduct rigorous statistical comparisons is metal grade ammonium hydroxide (VWR, West Chester,
- in murine models: (i) hydride generation (HG), where arsenicals et al. (2015), who evaluated several protease digestions of chicken
- and (ii) high-performance liquid chromatographic (HPLC) separa digestion methods for chicken liver. A control papain solution
- (Styblo et al. 2021), whereas HPLC separation is easily and Fisher Scientific) was made and incubated overnight with shak
- try (ICPMS) and is highly sensitive for detecting and identifying icals, arsenic stock solutions were added to papain or pepsin
- arsenic species. HPLC-ICPMS has proven to be more broadly used solutions at a final concentration of 5 µg/l and incubated over
- among labs and is the most cited in arsenic exposure research. night as described for control solutions. To evaluate digestion of
- With respect to animal tissues, a robust protocol for HPLC-ICPMS tissue, 3 replicate 0.1 g samples from the liver of an arsenic-
- 0.1 g samples from the liver of an iAsIII-exposed mouse (10 µg per
- dimethylarsinic acid, DMAV). In a separate study, the protocol
- Following incubation, samples were centrifuged at 12,000 rpm for
- trifugation at 12,000 rpm for 30 min at 4 � C. Filtered samples were
- kept at −80 � C until HPLC-ICPMS analysis.
Implications
This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.
Wiki pages this source may touch
- Fish — marine, predatory (tuna, swordfish, shark, king mackerel)
- Fish — marine, non-predatory (sardines, anchovies, salmon, cod)
- Shellfish (shrimp, crab, lobster, clams, oysters, mussels)
- Arsenic
Verification notes
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Update history
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