Iodopropynyl butylcarbamate, commonly abbreviated as IPBC, is a preservative used around the world in paints, coatings, wood preservatives, personal care products and cosmetics. Because it is a biocide, questions about its safety are common. This article reviews what IPBC is, what the safety science says, and how it should be used within established limits.
What Is IPBC?
IPBC is a water-soluble preservative belonging to the carbamate family of biocides. Its full chemical name is 3-iodo-2-propynyl butylcarbamate, and its CAS registry number is 55406-53-6. IPBC was developed in the 1970s and has a long history of effective use as an antifungal technology. It works by interfering with fungal cell metabolism, making it highly effective against molds, mildew and other fungi at very low concentrations.
What Is IPBC Used For?
IPBC is a fungicide and antimicrobial used as a preservative in a broad range of products, including:
Paints, coatings and wood preservatives
Adhesives and emulsions
Metalworking and cutting fluids
Oil recovery drilling mud and packer fluids
Plastics, textiles, inks and paper coatings
Personal care and cosmetic products
In these applications it protects the product itself from fungal spoilage rather than acting on the user, which is why concentration limits are set to keep exposure well below any safety concern.
Is IPBC Safe to Use? The CIR Safety Assessment
The safety of IPBC as a cosmetic ingredient has been formally evaluated by the Cosmetic Ingredient Review Expert Panel, an independent body that assesses the safety of cosmetic ingredients. The panel reviewed the available scientific data and concluded that iodopropynyl butylcarbamate is safe as a cosmetic ingredient at concentrations less than or equal to 0.1 percent. The panel also specified that IPBC should not be used in products intended to be aerosolized, because inhalation of the aerosolized ingredient raises different exposure concerns. These conclusions form the basis of safe-use guidance for formulators.
Regulatory Limits and Concentration Guidance
Beyond the CIR conclusion, IPBC is subject to preservative limits in several regulatory systems. In the European Union, for example, cosmetic preservatives are controlled under Regulation (EC) No 1223/2009, and IPBC is permitted with specified maximum concentrations and use conditions. Formulators should always verify the applicable limit for their market and product category, and should keep concentrations at or below 0.1 percent in cosmetic products, with aerosolized formats avoided entirely. In industrial products such as paints and metalworking fluids, higher use levels may be permitted, but occupational exposure should be controlled through ventilation and protective measures.
Safe Handling and Application Considerations
For industrial users, IPBC is typically handled as a concentrated technical material or as a diluted preservative solution. Safe practice includes wearing appropriate gloves and eye protection, avoiding inhalation of dust or mist, and storing the material in closed containers away from strong acids and oxidizing agents. For formulators, the key points are accurate dosing within the permitted range, thorough mixing to ensure uniform distribution, and clear labeling of the final product. End users of finished consumer products at regulated concentrations do not normally need special precautions.
Frequently Asked Questions
What does IPBC stand for?
IPBC stands for iodopropynyl butylcarbamate, also written as 3-iodo-2-propynyl butylcarbamate, a carbamate-family biocide with the CAS number 55406-53-6.
Is IPBC safe in cosmetics?
The CIR Expert Panel concluded that IPBC is safe as a cosmetic ingredient at concentrations of 0.1 percent or less, and it should not be used in products intended to be aerosolized.
What is IPBC used for in paint?
In paints and coatings, IPBC is used as an in-can preservative to prevent fungal growth and spoilage of the wet product during storage and application.
Is IPBC a fungicide?
Yes, IPBC is primarily a fungicide and antimicrobial, effective against molds and mildew at very low concentrations.
Can IPBC be used in spray products?
IPBC should not be used in products intended to be aerosolized, according to the CIR safety assessment, because of inhalation exposure concerns.
What concentration of IPBC is allowed?
In cosmetic products, IPBC is considered safe at concentrations up to 0.1 percent. Regulatory limits may vary by region and product type, so the applicable limit for each market should be verified.
