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For informational purposes only — not medical advice. Always consult a dermatologist for skin concerns.

MCI/MI

1% line markerAI-analyzed

INCI: METHYLCHLOROISOTHIAZOLINONE & METHYLISOTHIAZOLINONE

preservative

What it does

A highly effective preservative blend commonly used in rinse-off cosmetic products to prevent microbial growth. Its use in leave-on products is restricted due to potential sensitization.

Skin Concerns

No specific concern data available

Safety & Science

Safety summary

Highly effective preservative. Known to be a strong sensitizer, especially in leave-on products. Its use is heavily regulated and restricted to rinse-off products at very low concentrations in many regions.

1% line marker

This ingredient is commonly used as a marker to identify where ingredients drop below 1% concentration on the label.

Found In Products

Related Ingredients

At a Glance

INCI Name: METHYLCHLOROISOTHIAZOLINONE & METHYLISOTHIAZOLINONE
Common Name: MCI/MI
Functions: preservative
Products: 2 products

For informational purposes only. This is not medical advice. Always patch test new products and consult a dermatologist for skin concerns.

MCI/MI — Skincare Ingredient Guide — Dermasift — Dermasift