Sulfur dioxide (SO₂)
CAS: 7446-09-5
Moderate Risk (Adults)
Safety Summary
Hazard Profilehazardous
Risk (Adults)Moderate
Risk (Children)Moderate
Regulatory Status
SummaryIARC: Group 3 | California Prop 65 listed
Molecular FormulaO2S
Molecular Weight64.07
Sources
These citations are the ones recorded for the human adult context.
- US EPA National Ambient Air Quality Standards for Sulfur Dioxide REGULATORY · 2010
- WHO Air Quality Guidelines for Sulfur Dioxide (Global Update 2021) REGULATORY · 2021
- ATSDR Toxicological Profile for Sulfur Dioxide REPORT · 1998
- § 1910.1000 Air contaminants. REGULATORY
- IARC Monographs, List of Classifications REGULATORY · 2026
- ECHA Annex VI to CLP: the unofficial Excel table (up to and including the 23rd ATP) (secondary: unofficial by its own statement) REGULATORY
- identity database ECHA CHEM, Download all substances: REACH registrations (ECHA's own list of REACH-registered substances) REGULATORY · 2026
- NIOSH Pocket Guide to Chemical Hazards - Sulfur dioxide (7446-09-5) (reached from the NPG CAS index npgdcas.html, archived 2026-09-25) REGULATORY
- Industry Code of Practice on Chemicals Classification and Hazard Communication (DOSH Malaysia) REGULATORY
- where to look PubChem: Toxicity section (CID 1119) PUBCHEM
- L_2017027EN.01011501.xml REGULATORY
- OEHHA Proposition 65 List of Carcinogens or Reproductive Toxicants (CSV, list date 31-Jul-26) REGULATORY
- where to look CAMEO Chemicals, as recorded by PubChem (Experimental Properties, CID 1119; where-to-look, not a source of this value) DATABASE · 2026
- where to look Hazardous Substances Data Bank (HSDB), as recorded by PubChem (Experimental Properties, CID 1119; where-to-look, not a source of this value) DATABASE · 2026
Same data as the API response, which is open and needs no key. The full per-record source list is available to authenticated callers.
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