Methylisothiazolinone (2682-20-4) (C4H5NOS)

Methylisothiazolinone (MIT) is a highly effective preservative from the isothiazolinone group, widely used for its strong antimicrobial activity. It appears as a colorless to pale yellow liquid, highly soluble in water, and stable under normal storage conditions. It is effective against bacteria, fungi, and algae, even at low concentrations.
It is commonly used in personal care and cosmetic products such as shampoos, conditioners, liquid soaps, and lotions to prevent microbial contamination and extend shelf life. In industrial applications, it is used in paints, coatings, adhesives, and cooling water systems as a biocide. It is valued for its broad-spectrum efficacy and cost-effectiveness. However, due to potential skin sensitivity issues, its use is strictly regulated in many regions, especially in leave-on cosmetic products, to ensure consumer safety.