Quaternary Ammonium Compounds Fact Sheet
Published in November 2021
This fact sheet is part of a series of chemical fact sheets developed by TURI to help Massachusetts companies, community organizations and residents understand the use of toxic chemicals, their effects on human health and the environment, and safer alternatives.
What are Quaternary Ammonium Compounds?
Quaternary ammonium compounds (“QACs” or “quats”) are a broad class of several hundred chemicals. QACs were first discovered in the early 1940s and used mainly as active ingredients in antimicrobials, disinfectants, sanitizers, and surfactants. QACs also have many uses beyond disinfection, including wood preservatives, herbicides, eye drops, mouthwashes, nasal sprays, detergents and shampoos, dryer sheets and fabric softeners.
QACs remain largely used in the United States as ingredients in antimicrobial products for use in consumer and institutional cleaning and disinfecting. Applications range from domestic to agricultural, industrial, and clinical. These products can be found in restaurants, medical settings, food production facilities, and households. They are considered to be effective against most vegetative bacteria, enveloped viruses, and some fungi. Ready-to-use products may contain 0.08-20% active QAC ingredients, and industrial concentrates can contain 20-80% active QAC ingredients.
Although QACs have been used for over 80 years, they have had a recent increase in use. The demand for QAC-based disinfectants rose significantly as a result of the global SARS-CoV-2 pandemic. More than half of the products listed on the U.S. EPA’s "List N: Disinfectants for Coronavirus" are QAC based. As new QAC-based coatings and disinfectant formulations are introduced and overall use increases, environmental health and safety concerns about QAC exposure are also increasing. In 2020 alone, more than 700 hundred papers were published related to QAC research.