CAS number
CAS 123-91-1 Dioxane
CAS 123-91-1 · EC 204-661-8 · Index No 603-024-00-5
Where CAS 123-91-1 appears: every table entry that prints it among its identifiers, in the newest version of each act this record holds, and every recorded change to those entries. Many entries name a group of substances and print no number, so absence here is not absence from the law. Not legal advice.
Where it appears now
CLP Annex VI section 3, Index No 603-024-00-5
Last changed in the version in force , by Regulation (EU) 2021/849, the act that change names · Annex VI on this site
| Index No | Chemical name | EC No | CAS No | Classification | Labelling | Specific Conc. Limits, M-factors and ATEs | Notes | |||
|---|---|---|---|---|---|---|---|---|---|---|
| Hazard Class and Category Code(s) | Hazard statement Code(s) | Pictogram, Signal Word Code(s) | Hazard statement Code(s) | Suppl. Hazard statement Code(s) | ||||||
| 603-024-00-5 | 1,4-dioxane | 204-661-8 | 123-91-1 | Flam. Liq. 2 Carc. 1B STOT SE 3 Eye Irrit. 2 | H225 H350 H335 H319 | GHS02 GHS08 GHS07 Dgr | H225 H350 H335 H319 | EUH019 EUH066 | D | |
CLP Annex VI section 3, table 2, Index No 603-024-00-5
No change to this entry since the first version the record holds, in force 1 December 2010. · Annex VI on this site
| Index No | International Chemical Identification | EC No | CAS No | Classification | Labelling | Concentration Limits | Notes |
|---|---|---|---|---|---|---|---|
| 603-024-00-5 | 1,4-dioxane | 204-661-8 | 123-91-1 | F; R11-19 Carc. Cat. 3; R40 Xi; R36/37 R66 | F; Xn R: 11-19-36/37-40-66 S: (2-)9-16-36/37-46 | D |
Cosmetics Regulation Annex II, Reference number 343
No change to this entry since the first version the record holds, in force 11 July 2013. · Annex II on this site
| Reference number | Substance identification | ||
|---|---|---|---|
| Chemical name/INN | CAS number | EC number | |
| a | b | c | d |
| 343 | Dioxane | 123-91-1 | 204-661-8 |
Plant Protection Products Regulation Annex III, No 155
Last changed in the version in force , by Regulation (EU) 2026/1120, the act that change names · Annex III on this site
| No | Name | EC names/Other names | CAS number | EC number | Classification/Other properties |
|---|---|---|---|---|---|
| 155. | 1,4-dioxane | 123-91-1 | 204-661-8 | Carcinogenic cat. 1B |
REACH Annex XVII appendix 2, Index No 603-024-00-5
Last changed in the version in force , by Regulation (EU) 2021/2204, the act that change names · Annex XVII on this site
| Substances | Index No | EC No | CAS No | Notes |
|---|---|---|---|---|
| 1,4-Dioxane | 603-024-00-5 | 204-661-8 | 123-91-1 |
Look up a number
Type a CAS or EC number, with or without its hyphens, or an Index No into the search box at the top of the page: it reads 50000 as CAS 50-00-0. Every number is also listed by act on the substances page.
Its history
· added · Plant Protection Products Regulation Annex III, No 155
Recorded in the version in force , by Regulation (EU) 2026/1120, the act that change names. The change on its version page
| Identifiers | No | Name | EC names/Other names | CAS number | EC number | Classification/Other properties |
|---|---|---|---|---|---|---|
| No 155CAS 123-91-1EC 204-661-8 | 155. | 1,4-dioxane | 123-91-1 | 204-661-8 | Carcinogenic cat. 1B |
· amended · CLP Annex VI section 3, Index No 603-024-00-5
Recorded in the version in force , by Regulation (EU) 2021/849, the act that change names. The change on its version page
| Identifiers | Version | Index No | Chemical name | EC No | CAS No | Classification | Labelling | Specific Conc. Limits, M-factors and ATEs | Notes | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hazard Class and Category Code(s) | Hazard statement Code(s) | Pictogram, Signal Word Code(s) | Hazard statement Code(s) | Suppl. Hazard statement Code(s) | ||||||||
| Index No 603-024-00-5CAS 123-91-1EC 204-661-8 | Before | 603-024-00-5 | 1,4-dioxane | 204-661-8 | 123-91-1 | Flam. Liq. 2
Carc. | H225
| GHS02 GHS08 GHS07 Dgr | H225
| EUH019 EUH066 | D | |
| After | 603-024-00-5 | 1,4-dioxane | 204-661-8 | 123-91-1 | Flam. Liq. 2 Carc. 1B STOT SE 3 Eye Irrit. 2 | H225 H350 H335 H319 | GHS02 GHS08 GHS07 Dgr | H225 H350 H335 H319 | EUH019 EUH066 | D | ||
· added · REACH Annex XVII appendix 2, Index No 603-024-00-5
Recorded in the version in force , by Regulation (EU) 2021/2204, the act that change names. The change on its version page
| Identifiers | Substances | Index No | EC No | CAS No | Notes |
|---|---|---|---|---|---|
| Index No 603-024-00-5CAS 123-91-1EC 204-661-8 | 1,4-Dioxane | 603-024-00-5 | 204-661-8 | 123-91-1 |
Sources
- CLP: every version the record holds; rows read from EUR-Lex consolidated version 02008R1272-20270101, in force 1 January 2027 (external, EUR-Lex)
- Cosmetics Regulation: every version the record holds; rows read from EUR-Lex consolidated version 02009R1223-20260518, in force 18 May 2026 (external, EUR-Lex)
- Plant Protection Products Regulation: every version the record holds; rows read from EUR-Lex consolidated version 02009R1107-20260616, in force 16 June 2026 (external, EUR-Lex)
- REACH: every version the record holds; rows read from EUR-Lex consolidated version 02006R1907-20260622, detected 11 September 2026 (external, EUR-Lex)