Methylchloroisothiazolinone

INCI: METHYLCHLOROISOTHIAZOLINONE

Also known as: MCI, Kathon CG (with MI)

🔴 High Risk

Key Facts

CAS Number
26172-55-4
Category
preservative
Risk Level
high
Common Allergen
Yes
EU Status
Restricted
Max Concentration
0.0015% (MCI/MI mix, rinse-off only)
Found In
shampoo, body wash

What is Methylchloroisothiazolinone?

Preservative usually paired with MI. Potent sensitizer.

Allergy & Safety Information

Methylchloroisothiazolinone is classified as a high-risk ingredient. It is a known cause of allergic contact dermatitis. It is restricted or regulated in the EU. Individuals with sensitive skin or a history of contact allergies should avoid products containing this ingredient. A patch test is recommended before first use of any product containing Methylchloroisothiazolinone.

Allergen Note: Strong sensitizer, always used in combination with MI.

Cross-Reactions

If you react to Methylchloroisothiazolinone, you may also react to:

Safer Alternatives

These ingredients serve a similar function with lower allergy risk:

Frequently Asked Questions

Is Methylchloroisothiazolinone safe for sensitive skin?

Methylchloroisothiazolinone is a known allergen and is generally not recommended for sensitive skin. Consider patch testing before use.

What products contain Methylchloroisothiazolinone?

Methylchloroisothiazolinone is commonly found in shampoo, body wash.

What does Methylchloroisothiazolinone do in cosmetics?

Methylchloroisothiazolinone functions as a preservative in formulations. Strong sensitizer, always used in combination with MI.

Is Methylchloroisothiazolinone causing YOUR skin reactions?

SkinDetekt tracks your products and reactions to find your personal triggers. Download the app to find out.

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