Methylisothiazolinone (MI) is a widely used preservative and biocide.
Avoidance requires reading the product labels, package inserts, Material Safety Data Sheets (MSDS), and on occasion, direct communication with the manufacturer.
Skin contact with Methylisothiazolinone (MI) is required for it to cause a rash. Discontinuation of exposure to products containing Methylisothiazolinone (MI) should result in improvement and/or resolution of your dermatitis. By law, all products made in the US for topical use have the ingredients listed either on the product package or the box that contains it, so check the labeling of your skin care products for this ingredient. If there is no information, ask your pharmacist or call the company directly. At work, request a material safety data sheet (MSDS) to help identify potential sources of exposure.