MI is generally associated with MCI, in Kathon? CG, MCI/MI, and Euxyl? K 100. This preservative is currently used in water-based products such as cosmetics, paints, and glues. Skin contact with concentrated solution can cause severe irritant dermatitis.
 K. Yazar, M. D. Lundov, A. Faurschou, M. Matura, A. Boman, J. D. Johansen, C. Lidén (2015) Methylisothiazolinone in rinse-off products causes allergic contact dermatitis: a repeated open-application study, 173, 115-122
A potent biocide useful for controlling microbial growth
Yellow Low melting Solid
ChEBI: A 1,2-thazole that is 4-isothiazolin-3-one bearing a methyl group on the nitrogen atom. It is a powerful biocide and preservative and is the minor active ingredient in the commercial product KathonTM.
2-Methyl-4-isothiazolin-3-one is a isothiazolinone based biocide and preservative used in personal care products. 2-Methyl-4-isothiazolin-3-one is also used for controlling microbial growth in water-c
Methylisothiazolinone (also called 2-methyl-4-isothiazolin-3-one), is a powerful synthetic biocide and preservative within the group of isothiazolinones.
Methylisothiazolinone is used to control slime-forming bacteria, fungi, and algae in pulp/paper mills, cooling water systems, oil field operations, industrial process waters, and air washer systems. And it is incorporated into adhesives, coatings, fuels, metal working fluids, resin emulsions, paints, and various other specialty industrial products as a preservative. It is also used to control the growth of mold, mildew, and sapstain on wood products. It is generally recommended for use only in rinse-off and leave-on cosmetic products (maximum concentration of 100 ppm) as preservative such as shampoo, conditioner, hair color, body wash, lotion, sunscreen, mascara, shaving cream, baby lotion, baby shampoo, hairspray, makeup remover, liquid soaps, and detergents. Nevertheless, methylisothiazolinone is allergenic. It is reported that methylisothiazolinone in rinse-off products causes allergic contact dermatitis.