What Is Benzalkonium Chloride?

A 2022 review in Frontiers in Toxicology says benzalkonium chloride is probably the most widespread quaternary ammonium compound used as a preservative and antiseptic in medicines, cosmetics and cleaning agents. An EPA registration review work plan from March 2017 for alkyl dimethyl benzyl ammonium chloride, known as ADBAC, lists product types that include disinfectants, sanitizers, virucides, fungicides, tuberculocides, algaecides and water purifiers.

The FDA has deferred a decision on it as an over-the-counter antiseptic. The FDA granted deferral letters in March 2016 so that benzalkonium chloride could be studied further for consumer antiseptic hand and body washes used with water. In its December 2017 final rule on health care antiseptics, the FDA said it does not make a determination on whether benzalkonium chloride and five other deferred ingredients are generally recognized as safe and effective, and its December 2020 guidance says the consumer antiseptic rub final rule likewise includes no such determination for benzalkonium chloride, ethyl alcohol or isopropyl alcohol. The FDA antiseptic letters page, current as of August 2026, says that under the CARES Act, sponsor submissions in monograph order proceedings are confidential until the FDA issues a final order.

The 2022 Frontiers in Toxicology review calls benzalkonium chloride a recognized severe skin irritant used as an irritancy control in numerous experimental studies, and says it has been the quaternary ammonium compound most reported in the literature for contact allergies. NIOSH researchers writing in the American Journal of Infection Control in 2017 said the chemicals in cleaning and disinfecting products that can cause or worsen asthma because of their sensitizing or irritant properties include quaternary ammonium compounds.