GB 21027-2020 is a mandatory Chinese national standard for the safety of student articles. Section 4.1 sets maximum limits for migratable elements from a broad group of writing, coloring, correction, ink, and coated student articles, with a separate stricter row for colored modeling clay. The standard expresses the values as mg/kg of migratable element and references GB 6675.4-2014 for testing. The structured rows transcribe the HMI-controlled metals from Table 1; barium and selenium are omitted because they are outside the register vocabulary.
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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. When DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.
| Commit | Date | Change | Description |
|---|---|---|---|
| a8052bb | 2026-08-09 | minor | Narrative text revised |