Ethanolamine (MEA)
Also known as: MEA; monoethanolamine; 2-aminoethanol
INCI name: Ethanolamine
What it does
The alkaliser in most 'ammonia-free' colours. It does the same job as ammonia, raising the pH to open the hair, but is far less volatile, so there is little smell.
Benefits
Little odour during colouring.
Concerns & Risks
Not gentler by default. A manufacturer's laboratory study found MEA-based colours damaged hair more than ammonia-based ones, by up to 85% in the most extreme case. In a mouse study MEA combined with hydrogen peroxide caused skin inflammation and hair loss. The US Cosmetic Ingredient Review panel considers it safe only in rinse-off products formulated to be non-irritating. An ammonia-free dye can still contain PPD and the other allergens on this list.
Comedogenic rating
Non-comedogenic (0)
Suitable for
People who dislike the smell of ammonia, with the same allergy precautions as any permanent dye
Avoid if
Your scalp is broken or irritated; you are choosing it because you think 'ammonia-free' means allergy-free
Typical concentration
No EU maximum concentration. As a monoalkanolamine it must contain no more than 0.5% secondary amines, must not be used with nitrosating systems, and nitrosamines are capped at 50 µg/kg. India and US: no specific limit verified.