Li et al. 2017 - arsenic species in food-grade spirulina powder

Li and colleagues developed a two-step microwave-assisted extraction and IC-ICP-MS method for arsenic speciation in food-grade spirulina powder. They then applied the method to seven spirulina powder samples from Chinese production sites, reporting arsenite, arsenate, DMA(V), MMA(V), five unknown organic arsenic species, species sum, total arsenic, and recovery. Spirulina is handled here as an algae/cyanobacteria supplement powder; the taxonomy snapshot has no exact Spirulina ingredient slug.

Key numbers

Table 1 reports arsenic species in spirulina powder as ng g-1 (Average±SD, n=3). No unit conversion was performed. The source reports As(III) and As(V) separately; this page does not calculate a combined iAs value.

Table 1 footnotes state that - means not detected. As(III) was extracted with Milli-Q water under the optimized MAE temperature and time; As(V) was reported after subtracting the concentration obtained by Milli-Q-water extraction; total As was from digestion with HNO3-H2O2 (5:1, v/v); recovery was calculated as (species sum/total As) × 100.

The abstract and results summarize the same dataset as follows:

• As(V) was detected in all seven spirulina samples at 170-394 ng g-1, accounting for 8-100% of species sum.
• As(III) was detected in five provinces except Hainan and Guangxi at 28-147 ng g-1, accounting for 2-13% of species sum.
• DMA(V) was detected in six provinces except Guangxi at 32-839 ng g-1, accounting for 7-24% of species sum.
• MMA(V) was detected only in the Yunnan sample at 67±3 ng g-1.
• Five unknown organic arsenic compounds were detected except in the Guangxi sample; the results text reports their range as 38-2196 ng g-1, accounting for 9-62% of species sum.
• The concluding remarks state that spirulina powder samples had total arsenic in the range 0.33-3.38 µg g-1 and that extraction recovered >96% of arsenic.

Method-performance values reported by the source:

• Yunnan spirulina extracted-As species sum was (3527±71) ng g-1; digested total As was (3384±68) ng g-1; extraction recovery was (104±2)%.
• Instrumental detection limits were 5.00-10.0 ng L-1 for As(III), DMA(V), MMA(V), and As(V).
• Method detection limits in spirulina samples were 0.1, 0.1, 0.2, and 0.2 ng g-1 for As(III), DMA(V), MMA(V), and As(V), respectively.
• Spiked extraction recovery for As(III) in the Yunnan spirulina sample was (105±1)%.

Methods (brief)

Food-grade spirulina powder samples were purchased from production sites in Inner Mongolia, Zhejiang, Fujian, Hainan, Guangxi, Jiangsu, and Yunnan, China. About 500 g was purchased at each site, sifted through 100 mesh, stored in valve bags, and kept in a desiccator.

For most arsenic species, about 0.04 g spirulina powder was extracted in 12.0 mL H2O2/H2O (1:5, v/v) in sealed PFA jars and PEEK cans using an ETHOS UP microwave extractor at 100°C for 20.0 min. Extracts were weighed, filtered through 0.22 µm polypropylene membranes, and analyzed by IC-ICP-MS with 80 ng mL-1 74Ge as internal standard. As(III) was extracted and analyzed by the same procedure using Milli-Q water instead of H2O2/H2O because the authors state that As(III) is oxidized to As(V) during the peroxide extraction. The IC-ICP-MS system used a Dionex ICS-1100 IC and NexION 300X ICP-MS with an IonPac AS23 anion-exchange column; a cation-exchange column was used to verify species in concentrated Yunnan spirulina extract.

Implications

This source adds a primary arsenic-speciation dataset for food-grade spirulina powder from China. It is routeable to algae/seaweed-based supplement and dietary-supplement powder rows, but the frontmatter leaves ingredients: [] because the closed vocabulary has no exact Spirulina/cyanobacteria ingredient slug. As(III) and As(V) are kept as source-reported species and are not collapsed into a hand-calculated iAs total.

Wiki pages this source may touch

• supplements-algae-seaweed-based
• dietary-supplements
• supplements-oral-solids-powders
• arsenic-total
• arsenic-inorganic

Verification notes

• Identity checks before writing found no DOI/title/cite-key duplicate for DOI 10.1002/jssc.201700618 or cite key li2017-spirulina-arsenic-speciation.
• The raw filename handle MFK_li2017 is already used by wiki/sources/li2017-jiangsu-rice-cadmium-transfer.md, a different Li et al. 2017 rice/cadmium paper from raw/Manual Fetch Kimi /June 8 New Folder With Items 3 2/li2017.pdf with DOI 10.1039/C6EM00631K. This page therefore uses disambiguated raw handle MFK_li2017-spirulina-arsenic-speciation and records the collision in near_duplicates.
• All Key numbers were rechecked against /tmp/hmi-seaweed-039.txt, extracted with pdftotext -layout. Table 1 species values, footnotes, and method-performance values are transcribed directly.
• Units and bases are preserved as ng g-1, µg g-1, ng L-1, %, g, mL, °C, and min; no unit conversion was performed.
• Speciation check: As(III), As(V), DMA(V), MMA(V), and unknown organic arsenic species remain separate. No total arsenic value is promoted to iAs, and no source-unreported As(III)+As(V) sum is calculated.
• Brand firewall: the source reports production-site provinces, not consumer brands; no brand-linked contamination values are reproduced.
• Missing-slug check: taxonomy snapshot has no exact spirulina or cyanobacteria ingredient slug. Frontmatter leaves ingredients: [] and uses existing product slugs for algae/seaweed-based supplements, dietary supplements, and oral-solid powders.

Page history

The five most recent substantive edits to this page. The full version history lives in git; when DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.