Methylisothiazolinone (MI)

We use preservatives to keep home and personal care products in good condition: without them, they could be spoiled by bacteria, yeasts and moulds. We choose our preservative ingredients carefully, making sure they are safe and effective to people who use our products.

Woman conditioning her hair

Methylisothiazolinone (MI) is a preservative used in the personal care industry, however there are now concerns it may trigger allergies in some people. We have removed MI from our leave-on personal care products. For rinse-off personal care products, we are reducing MI levels globally to ensure we meet new regulatory requirements.

In our personal care products, the presence of MI is shown in the ingredients list so that any person who is allergic to MI can avoid using the product. We will continue to monitor scientific developments to ensure that all our products are safe, effective and fully compliant with regulatory requirements.

Your questions answered

What is MI?

MI enhances the safety and shelf-life of products by preventing the growth of bacteria and yeasts. Without preservatives like MI, products could start to smell unpleasant, change colour or grow moulds which can produce toxins which are harmful to health.

Does MI cause allergies?

Most people who use products containing MI have no allergic reaction. However, due to extensive use of MI across personal care and other product types over many years, dermatologists noticed an increase in the number of people with an allergy to it. Our Safety and Environmental Assurance Centre (SEAC) reviewed all relevant clinical data.

As a result, we have removed it from our leave-on personal care products and are reducing MI levels globally to ensure we meet the new regulatory requirements. Consumer safety is our top priority, if any new information becomes available we assess it and, if necessary, take action.

Some consumers may be allergic to MI, and thus we ensure we use only minimal levels, and when we do, we inform consumers through the ingredient list on pack and on our website, as well as on SmartLabel.

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