What chemical is chloromethyl isothiazolinone?

Chloromethylisothiazolinone (CMIT) is a powerful synthetic biocide and preservative. It is part of the isothiazolinone family and is widely used to control bacteria, fungi, and algae in water-based products.

Here are the key details about this chemical:

Identifiers: It is also known as Methylchloroisothiazolinone (MCI) and is often referred to by the abbreviations CMIT or MCI. Its CAS number is 26172-55-4.

Chemical Formula: C₄H₄ClNOS.

Common Use: It is the major active ingredient in the famous commercial product Kathon™ CG, where it is typically used in a mixture with Methylisothiazolinone (MIT) in a 3:1 ratio.

Applications: You can find it in products like shampoos, conditioners, water-based paints, adhesives, detergents, and industrial fuels.

Safety Concerns: CMIT is a known skin sensitizer and allergen. In its concentrated form, it is corrosive and can cause chemical burns. Consequently, its concentration in consumer products like cosmetics is strictly regulated (e.g., limited to low ppm levels).