Since 1976 CCLS has been the #1 Septic Treatment Additive recommended by contractors and pumpers. Formulated from naturally-occurring organisms. It needs no mixing, is non-toxic, non-hazardous, non-corrosive, and non-combustible. It emits no odors or harmful fumes. It will not harm the skin. humans or pets, although not intended for human consumption. CCLS contains no acids, caustics, chloride, or volatile organic compounds. CCLS is safe for the environment and completely safe to store and use in the home when used according to directions.