Beauty ingredient · Preservative

Methylisothiazolinone (MIT)

CAS
2682-20-4

A preservative used in rinse-off products and household cleaners; a common contact allergen.

  • Isothiazolinone preservative
  • Preservative
  • Expert review pending

Concern level

High concern Level 3 of 4 How concern levels work

A regulatory warning or restriction somewhere, or strong evidence of harm at typical intake. The concern level sets how many points methylisothiazolinone (MIT) costs on a product’s receipt.

What the evidence says

  • Contact allergenRegulatory

    A frequent cause of contact allergy; the EU banned methylisothiazolinone in leave-on products (2017) and limits it to 0.0015% in rinse-off products. [1][2][3]

Evidence tiers say how sure the evidence is, separately from how much it matters. About evidence tiers.

Rules around the world

How regulators treat Methylisothiazolinone (MIT)
WhereStatusDetailsDateSource
European Union Restricted Not allowed in leave-on products (from 2017); rinse-off products up to 0.0015%. Feb 12, 2017 [2]
Canada Restricted Not permitted in leave-on products; rinse-off up to 0.0015%. — [4]

“Banned” means explicitly prohibited or withdrawn after review; “not permitted” means never authorized there. We use each regulator’s own words.

Names GoodSwap recognizes on labels (7)
  • mi
  • mit
  • methylisothiazolone
  • methylisothiazolinone
  • methylisothiazolinone mi
  • methylisothiazolinone mit
  • 2 methyl 4 isothiazolin 3 one

Sources

  1. Commission Regulation (EU) 2016/1198 of 22 July 2016 amending Annex V to Regulation (EC) No 1223/2009 (Methylisothiazolinone in leave-on products)

    European Union (Official Journal) · Jul 22, 2016 · Law

    “this substance should therefore be banned in leave-on products.”

    eur-lex.europa.eu

  2. Commission Regulation (EU) 2017/1224 of 6 July 2017 amending Annex V to Regulation (EC) No 1223/2009 (Methylisothiazolinone in rinse-off products)

    European Union (Official Journal) · Jul 6, 2017 · Law

    “a concentration up to 0,0015 % (15 ppm) Methylisothiazolinone is considered safe for the consumer from the point of view of induction of contact allergy.”

    eur-lex.europa.eu

  3. Commission Regulation (EU) No 1003/2014 of 18 September 2014 amending Annex V to Regulation (EC) No 1223/2009 (Methylchloroisothiazolinone and Methylisothiazolinone)

    European Union (Official Journal) · Sep 18, 2014 · Law

    “up to a maximum authorised concentration of 0,0015 % in rinse-off cosmetic products, apart from its skin sensitising potential.”

    eur-lex.europa.eu

  4. Cosmetic Ingredient Hotlist: prohibited and restricted ingredients

    Health Canada · Aug 13, 2025 · Regulator

    “The following ingredients are only permitted in cosmetic products under the conditions of use specified below:”

    canada.ca