Regulatory Status
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Safety Data
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Safety Opinions
Official safety assessments from the Scientific Committee on Consumer Safety (SCCS) and Cosmetic Ingredient Review (CIR).
Expert Verdict
HIGH CONCERN. MCI is used only as the 3:1 MCI/MI blend and is among the top-ranked contact allergens in EU clinical surveillance. Banned in leave-on cosmetics in the EU; permitted in rinse-off at 0.0015% as the blend. Avoid in all leave-on applications globally. Isothiazolinone contact allergy prevalence has declined in markets where EU restrictions are in force.
Regulatory Flags
Frequently Asked Questions
Is Methylchloroisothiazolinone safe in cosmetics?
HIGH CONCERN. MCI is used only as the 3:1 MCI/MI blend and is among the top-ranked contact allergens in EU clinical surveillance. Banned in leave-on cosmetics in the EU; permitted in rinse-off at 0.0015% as the blend. Avoid in all leave-on applications globally. Isothiazolinone contact allergy prevalence has declined in markets where EU restrictions are in force. The EU classifies Methylchloroisothiazolinone as "restricted". Safety rating: POOR. This ingredient has been reviewed by cir.
Is Methylchloroisothiazolinone allowed in the EU?
Methylchloroisothiazolinone EU regulatory status: restricted. Maximum allowed concentration: 0.0015% in rinse-off cosmetics only as MCI/MI 3:1 blend; prohibited in leave-on cosmetics. This is based on EU Regulation 1223/2009 and its amendments.
What does Methylchloroisothiazolinone do in cosmetics?
Methylchloroisothiazolinone functions as: Preservative. It is classified as a Preservative in our database. CAS number: 26172-55-4.
What is the Margin of Safety for Methylchloroisothiazolinone?
not established The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.
Compliance Tools
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Related Ingredients
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