Potassium hydroxide/sodium hydroxide in EU cosmetics: Annex III, entry 15a
Potassium hydroxide/sodium hydroxide: the entry states maximum concentrations of (a) 5 % (4), 2 % (4), 4,5 % (4) by product type and conditions, see below. Annex III, entry 15a, Regulation (EC) No 1223/2009, consolidated 18 May 2026.
- Annex
- III: List of substances which cosmetic products must not contain except subject to the restrictions laid down
- Reference number
- 15a
- Chemical name/INN
- Potassium or sodium hydroxide (20)
- Name of Common Ingredients Glossary
- Potassium hydroxide/sodium hydroxide
- CAS number
- 1310-58-3/1310-73-2
- EC number
- 215-181-3/215-185-5
- Version
- Consolidated version of 18 May 2026
- Official source
- Regulation (EC) No 1223/2009, consolidated text
Official wording: restrictions
- Product type, body parts: (a) Nail cuticle solvent | Maximum concentration in ready for use preparation: (a) 5 % (4)
- Product type, body parts: (b) Hair straightener | Maximum concentration in ready for use preparation: 2 % (4) | Other: General use
- Maximum concentration in ready for use preparation: 4,5 % (4) | Other: Professional use
- Product type, body parts: (c) pH adjuster for depilatories | Other: (c) pH < 12,7
- Product type, body parts: (d) Other uses as pH adjuster | Other: (d) pH < 11
Official wording: conditions of use and warnings
(a) Contains alkali
Avoid contact with eyes
Can cause blindness
Keep out of reach of children
Contains alkali
For professional use only
(c) Keep out of reach of children
Notes referred to in this entry
- (4) The quantity of sodium, potassium or lithium hydroxide is expressed as weight of sodium hydroxide. In cases of mixtures, the sum should not exceed the limits given in column g.
- (20) For other uses of potassium hydroxide, see Annex III, No 15d.
Same CAS number in other entries of the annexes
Want the limits by product type?
If we publish the entries grouped by product type (shampoo, sunscreen, toothpaste), we write to you once. We use the email for nothing else.