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Ingredient

Methylchloroisothiazolinone

A preservative used in a fixed mixture with methylisothiazolinone, permitted in the EU in rinse-off products only.

  • Preservative

What it is there to do

  • Preservative

    Keeps the product free of microbial growth in use.

Where this comes up

The notes BeautySignal puts beside this ingredient when it is on a label.

  • Subject to a regulatory restriction

    One or more ingredients in this product are restricted in at least one market. The restriction is usually a concentration limit or a limit on the type of product.

    Why we mention it

    Points at a named instrument rather than implying a general hazard. The specific provision is shown with the ingredient.

What the rules say

Each line names the rule it comes from. A limit is not a warning.

  • EU · Restricted

    Regulation (EC) No 1223/2009, Annex V, entry 39

    What it sets out

    Where it applies: Rinse-off products only

    Maximum 0.0015 % of a 3:1 mixture with methylisothiazolinone. Packs don't print concentrations and we hold none, so no page here measures a product against it.

What we don't know

  • Where it comes from — plant, mineral, synthetic — isn't recorded.
  • How much of it is used in any particular product. We hold no concentrations at all.

Also written as

  • MCI
  • Methylchloroisothiazolinone and Methylisothiazolinone

This is information about an ingredient, not medical advice, and not a judgement about any product that contains it. Back to the reference.

Methylchloroisothiazolinone · BeautySignal