Methylisothiazolinone (MI) is a very effective preservative, but it is also a well-known contact-allergy sensitizer.
European safety guidance restricts MI to rinse-off cosmetics at very low concentration and does not support its use in leave-on cosmetics. In SESH it is currently listed in a cleanser, so the rinse-off context matters.
Usage & cautions
People with known isothiazolinone allergy should avoid it. Its concentration must comply with the market where the product is sold.
Information approach
Consumer-friendly summaries are informed by established cosmetic ingredient references such as INCIDecoder and Paula’s Choice Ingredient Dictionary, while avoiding turning ingredient-level evidence into medical claims about the finished product.
Might be time to restock
Based on when this product was added to cart on this device. Check your bottle before reordering.
