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OCTYLISOTHIAZOLINONE

Description

Octylisothiazolinone is a potent synthetic biocide and preservative commonly used in personal care products, cosmetics, and industrial formulations. This colorless, oil-soluble compound belongs to the isothiazolinone family and is known for its broad-spectrum antimicrobial activity against bacteria, fungi, and yeasts. Its primary function is to extend product shelf life by inhibiting microbial growth.

The ingredient's molecular structure allows it to penetrate microbial cell membranes, disrupting cellular processes and ultimately leading to cell death. Octylisothiazolinone is effective at low concentrations, typically ranging from 0.0005% to 0.01% in finished products. Its stability across a wide pH range and compatibility with various formulation types make it a versatile preservative option.

While effective, octylisothiazolinone has been associated with skin sensitization in some individuals. Regulatory bodies, including the European Union, have established maximum concentration limits for its use in rinse-off and leave-on products. Formulators must carefully balance its preservative efficacy with potential sensitization risks. Alternative preservatives or combination systems are often considered to minimize concentration while maintaining product integrity and safety.