EC number

EC 204-617-8 Hydroquinone

CAS 123-31-9 · EC 204-617-8 · Index No 604-005-00-4

Where EC 204-617-8 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 604-005-00-4

Last changed in the version in force 1 December 2010, by Regulation (EC) No 790/2009, the act that change names · Annex VI on this site

Annex VI section 3, table 1
Index No	Chemical name	EC No	CAS No	Classification		Labelling			Specific Conc. Limits, M-factors and ATEs	Notes
Index No	Chemical name	EC No	CAS No	Hazard Class and Category Code(s)	Hazard statement Code(s)	Pictogram, Signal Word Code(s)	Hazard statement Code(s)	Suppl. Hazard statement Code(s)	Specific Conc. Limits, M-factors and ATEs	Notes
604-005-00-4	1,4-dihydroxybenzene; hydroquinone; quinol	204-617-8	123-31-9	Carc. 2 Muta. 2 Acute Tox. 4 * Eye Dam. 1 Skin Sens. 1 Aquatic Acute 1	H351 H341 H302 H318 H317 H400	GHS05 GHS08 GHS07 GHS09 Dgr	H351 H341 H302 H318 H317 H400		M=10

CLP Annex VI section 3, table 2, Index No 604-005-00-4

Last changed in the version in force 1 December 2010, by Regulation (EC) No 790/2009, the act that change names · Annex VI on this site

Annex VI section 3, table 2
Index No	International Chemical Identification	EC No	CAS No	Classification	Labelling	Concentration Limits	Notes
604-005-00-4	1,4-dihydroxybenzene; hydroquinone; quinol	204-617-8	123-31-9	Carc. Cat. 3; R40 Muta. Cat. 3; R68 Xn; R22 Xi; R41 R43 N; R50	Xn; N R: 22-40-41-43-68-50 S: (2-)26-36/37/39-61	N; R50: C ≥ 2,5 %

Cosmetics Regulation Annex II, Reference number 1339

Last changed in the version in force 11 July 2013, by Regulation (EU) No 344/2013 and Regulation (EU) No 1197/2013, the acts that change names · Annex II on this site

Annex II, table 1
Reference number	Substance identification
Reference number	Chemical name/INN	CAS number	EC number
a	b	c	d
1339	1,4-Dihydroxybenzene (Hydroquinone), with the exception of entry 14 in Annex III	123-31-9	204-617-8

Cosmetics Regulation Annex III, Reference number 14

Last changed in the version in force 11 July 2013, by Regulation (EU) No 344/2013 and Regulation (EU) No 1197/2013, the acts that change names · Annex III on this site

Annex III, table 1
Reference number	Substance identification				Restrictions			Wording of conditions of use and warnings
Reference number	Chemical name/INN	Name of Common Ingredients Glossary	CAS number	EC number	Product type, body parts	Maximum concentration in ready for use preparation	Other	Wording of conditions of use and warnings
a	b	c	d	e	f	g	h	i
14	Hydroquinone	Hydroquinone	123-31-9	204-617-8	Artificial nail systems	0,02 % (after mixing for use)	Professional use only	For professional use only Avoid skin contact Read directions for use carefully

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

11 July 2013 · added · Cosmetics Regulation Annex II, Reference number 1339

Recorded in the version in force 11 July 2013, by Regulation (EU) No 344/2013 and Regulation (EU) No 1197/2013, the acts that change names. The change on its version page

Added entries, Annex II, table 1
Identifiers	Reference number	Substance identification
	Reference number	Chemical name/INN	CAS number	EC number
	a	b	c	d
Reference number 1339CAS 123-31-9EC 204-617-8	1339	1,4-Dihydroxybenzene (Hydroquinone), with the exception of entry 14 in Annex III	123-31-9	204-617-8

11 July 2013 · amended · Cosmetics Regulation Annex III, Reference number 14

Recorded in the version in force 11 July 2013, by Regulation (EU) No 344/2013 and Regulation (EU) No 1197/2013, the acts that change names. The change on its version page

Amended entries, Annex III, table 1
Identifiers	Version	Reference number	Substance identification				Restrictions			Wording of conditions of use and warnings
		Reference number	Chemical name/INN	Name of Common Ingredients Glossary	CAS number	EC number	Product type, body parts	Maximum concentration in ready for use preparation	Other	Wording of conditions of use and warnings
		a	b	c	d	e	f	g	h	i
Reference number 14CAS 123-31-9EC 204-617-8	Before	14	Hydroquinone	Hydroquinone	123-31-9	204-617-8	~~(a) Oxidising colouring agent for hair dyeing~~	~~0,3~~ %	~~General~~ use ~~Not to be used on eyebrows~~	~~Do not~~ use ~~to dye eyelashes or eyebrows Rinse eyes immediately if the product comes into~~ contact ~~with them Contains Hydroquinone~~
	Before	14	Hydroquinone	Hydroquinone	123-31-9	204-617-8	~~(a) Oxidising colouring agent for hair dyeing~~	~~0,3~~ %	~~Professional use~~	~~For professional use only Contains hydroquinone Rinse eyes immediately if product comes into contact with them~~
	After	14	Hydroquinone	Hydroquinone	123-31-9	204-617-8	Artificial nail systems	0,02 %(after mixing for use)	Professional use only	For professional use only Avoid skin contact Read directions for use carefully

1 December 2010 · amended · CLP Annex VI section 3, Index No 604-005-00-4

Recorded in the version in force 1 December 2010, by Regulation (EC) No 790/2009, the act that change names. The change on its version page

Amended entries, Annex VI section 3, table 1
Identifiers	Version	Index No	International Chemical Identification	EC No	CAS No	Classification		Labelling			Specific Conc. Limits, M-factors
Identifiers	Version	Index No	International Chemical Identification	EC No	CAS No	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 604-005-00-4CAS 123-31-9EC 204-617-8	Before	604-005-00-4	1,4-dihydroxybenzene; hydroquinone; quinol	204-617-8	123-31-9	Carc. 2 Muta. 2 Acute Tox. 4 * Eye Dam. 1 Skin Sens. 1 Aquatic Acute 1	H351 H341 H302 H318 H317 H400	GHS08 ~~GHS05~~ GHS07 GHS09 Dgr	H351 H341 H302 H318 H317 H400
Index No 604-005-00-4CAS 123-31-9EC 204-617-8	After	604-005-00-4	1,4-dihydroxybenzene; hydroquinone; quinol	204-617-8	123-31-9	Carc. 2 Muta. 2 Acute Tox. 4 * Eye Dam. 1 Skin Sens. 1 Aquatic Acute 1	H351 H341 H302 H318 H317 H400	GHS05 GHS08 GHS07 GHS09 Dgr	H351 H341 H302 H318 H317 H400		M=10

1 December 2010 · amended · CLP Annex VI section 3, table 2, Index No 604-005-00-4

Recorded in the version in force 1 December 2010, by Regulation (EC) No 790/2009, the act that change names. The change on its version page

Amended entries, Annex VI section 3, table 2
Identifiers	Version	Index No	International Chemical Identification	EC No	CAS No	Classification	Labelling	Concentration Limits	Notes
Index No 604-005-00-4CAS 123-31-9EC 204-617-8	Before	604-005-00-4	1,4-dihydroxybenzene; hydroquinone; quinol	204-617-8	123-31-9	Carc. Cat. 3; R40 Muta. Cat. 3; R68 Xn; R22 Xi; R41 R43 N; R50	Xn; N R: ~~22-40-41-43-50-68~~ S: (2-)26-36/37/39-61
Index No 604-005-00-4CAS 123-31-9EC 204-617-8	After	604-005-00-4	1,4-dihydroxybenzene; hydroquinone; quinol	204-617-8	123-31-9	Carc. Cat. 3; R40 Muta. Cat. 3; R68 Xn; R22 Xi; R41 R43 N; R50	Xn; N R: 22-40-41-43-68-50 S: (2-)26-36/37/39-61	N; R50: C ≥ 2,5 %

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)

Watch this substance