preservative
Methylisothiazolinone
Restricted·Strong evidence
A preservative that caused a wave of contact allergy in the 2010s. The EU banned it from leave-on products and tightly limits it in rinse-off ones. A genuine concern, not a myth.
Worth knowing
- Known contact sensitizer for some
- Restricted in the EU
Banned in leave-on cosmetics in the EU; limited to 0.0015% in rinse-off.
Gentler alternatives
Products with Methylisothiazolinone
References
Cosmetic information for general education, not medical advice. Concern is graded on cited evidence, never on hazard-score lists. See how we score.