Overview
García-Salgado et al. identified and quantified arsenosugar phospholipids and arsenic hydrocarbons in two dried commercial brown macroalgae, Wakame and Hijiki. The paper reports whole-powder total arsenic and lipid-soluble organoarsenic species, not inorganic arsenic. Values below therefore keep whole-powder total arsenic and individual arsenolipids separate.
Key numbers
The paper reports whole dry-powder total arsenic as µg As g-1 dry mass:
| Material | Species | Whole-powder tAs |
|---|---|---|
| Wakame | Undaria pinnatifida | 40 ± 3 µg As g-1 dry mass |
| Hijiki | Hizikia fusiformis | 113 ± 5 µg As g-1 dry mass |
The lipid fraction contained 6.7% of initial total arsenic for Wakame and 1.6% for Hijiki.
Table 2 quantifies arsenolipids in µg As kg-1 and as percentage of lipid arsenic. Data are mean ± s.d. from three analyses, each involving extraction, clean-up, and HPLC-ICPMS; column recoveries ranged from ~70 to 110%.
| Peak/band | Assigned structure | Wakame concentration | Wakame lipid As | Hijiki concentration | Hijiki lipid As |
|---|---|---|---|---|---|
| A | U1 | 10 ± 1 µg As kg-1 | 0.68 ± 0.08% | 9 ± 1 µg As kg-1 | 0.70 ± 0.08% |
| B | U2 | 46 ± 8 µg As kg-1 | 3.0 ± 0.9% | 53 ± 1 µg As kg-1 | 3.9 ± 0.2% |
| C | As-HC332 | 22 ± 3 µg As kg-1 | 1.4 ± 0.3% | 309 ± 16 µg As kg-1 | 22.9 ± 0.2% |
| D | As-HC360 | 82 ± 37 µg As kg-1 | 6 ± 3% | 35 ± 9 µg As kg-1 | 2.6 ± 0.6% |
| E | As-HC388 | 406 ± 121 µg As kg-1 | 27 ± 11% | 22 ± 2 µg As kg-1 | 1.7 ± 0.1% |
| E | As-PL930 / As-PL944 / As-PL956 / As-PL982 | Not quantified | - | Not quantified | - |
| F | As-PL958 | 426 ± 136 µg As kg-1 | 28 ± 12% | 251 ± 39 µg As kg-1 | 18 ± 2% |
| F | As-PL988 | 144 ± 52 µg As kg-1 | 10 ± 4% | 85 ± 3 µg As kg-1 | 6.3 ± 0.4% |
| G | As-PL956 / As-PL1012 | 200 ± 74 µg As kg-1 | 13 ± 6% | 58 ± 9 µg As kg-1 | 4.2 ± 0.6% |
| H | As-PL1014 | 226 ± 66 µg As kg-1 | 15 ± 6% | 48 ± 12 µg As kg-1 | 3.6 ± 0.8% |
| I | As-PL1042 | 27 ± 11 µg As kg-1 | 1.8 ± 0.5% | 32 ± 10 µg As kg-1 | 2.4 ± 0.8% |
| J | As-PL1070 | Not quantified | - | 21 ± 3 µg As kg-1 | 1.6 ± 0.1% |
Figure 2 states that As-HC332 and As-HC360 were present in both Wakame and Hijiki, while As-HC388 was present in Wakame but not Hijiki by the confirmatory GC-MS discussion; Table 2 nevertheless reports a small Hijiki As-HC388 HPLC-ICPMS quantified value of 22 ± 2 µg As kg-1.
For QA/QC, the paper reports NIES No. 9 Sargasso certified total arsenic 115 ± 5 µg As g-1 and measured 116 ± 2 µg As g-1 (n = 3).
Methods (brief)
Total arsenic analyses were performed on dry powders, extracts, or combined silica-column fractions by ICP-MS in helium collision-cell mode after microwave-assisted acid mineralization. Arsenolipids were extracted in triplicate from Wakame and Hijiki with chloroform/methanol, washed with 1% w/v bicarbonate solution, cleaned on silica, and analyzed by reversed-phase HPLC with simultaneous ICPMS and electrospray MS detection. HPLC used a Zorbax Eclipse XDB-C8 column with an acetic acid/methanol gradient; accurate masses were measured with an LTQ Orbitrap XL in FTMS high-resolution positive-scan mode.
Implications
This source adds seaweed organoarsenic speciation context for commercial Wakame and Hijiki. It should not be treated as an inorganic-arsenic occurrence paper: the quantified species are arsenosugar phospholipids, arsenic hydrocarbons, and two unidentified arsenolipid peaks. Downstream extraction should keep whole-powder total arsenic (tAs), lipid-fraction arsenic percentage, and named arsenolipid species distinct.
Related evidence
Update history
The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git.
| Commit | Date | Change | Description |
|---|---|---|---|
| b01ec52c31 | 2026-08-04 | major | 1 section added |
| 3171d069e3 | 2026-08-02 | major | 1 section added |
| 90a2f9a38e | 2026-07-30 | major | 1 section added and 1 removed; narrative text revised |
| eaa8eeeedf | 2026-07-27 | major | 1 section added |
| 50de6ab217 | 2026-07-27 | minor | Narrative text revised |