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Beauty · Preservatives

Is Methylchloroisothiazolinone Banned? EU vs US Status, Risks & Where It Hides

TL;DR: Methylchloroisothiazolinone is restricted in the EU but allowed in the US (preservatives).

INCI name Methylchloroisothiazolinone. CAS 26172-55-4.

Is Methylchloroisothiazolinone banned in the EU?

EU statusRestricted
US statusAllowed
Risk levelhigh
Where it shows upshampoo, conditioner, cleanser
CAS number26172-55-4

What is Methylchloroisothiazolinone?

Methylchloroisothiazolinone is a preservative (CMIT, usually paired with MIT) for rinse-off products.

Why is Methylchloroisothiazolinone used in personal-care products?

It is used for its preservative, coloring, UV-filtering, lightening or texture-enhancing properties.

Is Methylchloroisothiazolinone dangerous? Documented risks

A strong skin sensitizer; the EU bans it in leave-on products and tightly limits rinse-off use. The US is less restrictive.

Products that may contain Methylchloroisothiazolinone

How to avoid Methylchloroisothiazolinone: safer alternatives

Choose EU-compliant or 'free-from' formulations and read the INCI list. BannedPantry flags this ingredient and suggests safer swaps.

Frequently asked questions about Methylchloroisothiazolinone

Is Methylchloroisothiazolinone banned in the EU?

Methylchloroisothiazolinone is restricted under the EU Cosmetics Regulation (1223/2009), but it is allowed in US personal-care products.

Is Methylchloroisothiazolinone in US cosmetics?

Yes — Methylchloroisothiazolinone can still appear in US-sold cosmetics and personal-care products because US rules are far less restrictive than the EU's.

What products contain Methylchloroisothiazolinone?

Read the INCI ingredient list on the back of the package. Scan the barcode with BannedPantry to flag Methylchloroisothiazolinone automatically.

Are there safer alternatives to Methylchloroisothiazolinone?

Yes. Look for EU-compliant or 'free-from' formulations; BannedPantry suggests safer swaps when it detects Methylchloroisothiazolinone.

Is Methylchloroisothiazolinone in your bathroom cabinet?

Scan any product's barcode and instantly see if it contains Methylchloroisothiazolinone or other ingredients banned overseas.

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Related preservatives

Avoiding banned beauty ingredients? Check your food, too.

Sources

  1. EU Cosmetics Regulation Annex II (prohibited substances) EU Cosmetics Regulation 1223/2009
  2. EU-banned cosmetics ingredients and US impact RegASK
  3. Chemicals in cosmetics CHEM Trust

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