Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Environmental hazard

H421 — Harms public health and the environment by contributing to global warming

Environmental hazard statements describe harm to the aquatic environment, the ozone layer or the climate. No substance with a harmonised EU classification carries this code.

EU CLP: absentUS OSHA HazCom: absentUS HazCom 2012: absentUN GHS: current

01 · Wording

What H421 says

Official

Harms public health and the environment by contributing to global warming

Typical

Harms public health and the environment by contributing to global warming. How it usually reads on a label and on a safety data sheet. We show it separately rather than presenting a filled-in blank as the regulation's own text.

Source

UN GHS Rev.11 Annex 3 · Environmental hazards

UN GHS history

Introduced in Rev.11 (2025).

Rev.3 2009
Rev.4 2011
Rev.5 2013
Rev.6 2015
Rev.7 2017
Rev.8 2019
Rev.9 2021
Rev.10 2023
Rev.11 2025
added in Rev.11 (2025)

Added by UN GHS Rev.11 and unchanged through Rev.11 (2025). Jurisdictions that sit on an earlier revision do not have this code at all.

Nine editions of the UN model text, 86 hazard statements, 19 of which ever moved. Read the full story in what changed in UN GHS Rev.11.

Where H421 is current

GHS is a United Nations model text, revised every two years, and each jurisdiction adopts a revision on its own timetable. A code can be legally current in one system and deleted in another — that is normal, not an error.

JurisdictionBasisStatus of H421
EU CLP Regulation (EC) 1272/2008 CLP Annex IV, Part 2 (consolidated) not in this system
US OSHA HazCom 29 CFR 1910.1200 Appendix C UN GHS Rev.7 (final rule of 20 May 2024) not in this system
US HazCom 2012 legacy · GHS Rev.3 UN GHS Rev.3, Annex 3 not in this system
UN GHS Rev.11 (2025) UN GHS Rev.11, Annex 3 Current

Currently in force under: UN GHS. Sources: EU CLP · US OSHA HazCom · US HazCom 2012 · UN GHS

Substances carrying H421

No substance with a harmonised classification in CLP Annex VI carries this code. That does not mean it is unused — suppliers apply it to their own mixtures.

All hazard statements

The full list of H-codes with the jurisdiction switch lives on the hazard statements hub. For what to do about the hazard, see precautionary statements (P-codes).

Wording quoted from the regulation named above. Substance counts come from harmonised classifications in CLP Annex VI — the statements on a real product also depend on the supplier's own classification. Always check the supplier safety data sheet.

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