Kathon CG Worst Preservative No known benefits Kathon CG at a glance Also called Kathon™ Cosmetic Grade Combination of two sensitizing synthetic preservatives Can cause contact dermatitis Kathon CG description Kathon CG is the trade name for a combination of methylchloroisothiazolinone and methylisothiazolinone, which offers preservative benefit. Introduced into cosmetics in the mid-1970s, it elicited a great number of sensitizations in consumers. This led to it not being included in cosmetics other than rinse-off products. This blend is used in many products instead of parabens, despite the fact that parabens have a better safety track record and lower incidence of causing a sensitising reaction. Related ingredients: Methylisothiazolinone Methylchloroisothiazolinone