Ingredient

methylisothiazolinone

High risk

FunctionPreservative

What it is

Methylisothiazolinone (MI) is a preservative used to protect water-based products from microbial growth.

What it does

It keeps formulas safe and stable, and is effective at low concentrations, most often in rinse-off products.

Typical use

Found in shampoos, cleansers and similar products; its use in leave-on cosmetics is restricted in the EU following sensitisation concerns.

Who it suits / good to know

Those with sensitive or allergy-prone skin often choose to avoid it.

Safety

Graded high risk as a potent contact sensitiser associated with a rise in contact allergy, which is why regulators have tightened its use. Patch-test new products and avoid if you know you react to isothiazolinones. This is general information, not medical advice.

Why we grade it High: High risk - isothiazolinone preservative and potent contact sensitizer.
Cross-reference

Found in these DHALIORA products

Found in 0 DHALIORA products

Not currently in any DHALIORA product.

How grades are set — Risk reflects our own reading of publicly available safety data, an EWG-style reading shown at the worst-case grade we've assigned this ingredient across products. It isn't a third party's proprietary score, and it isn't medical advice. Always read the packaging and patch-test where indicated.
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