Reproductive & developmental toxicity of quaternary ammonium compounds†

Quaternary ammonium compounds are a class of chemicals commonly used as disinfectants in household and healthcare settings. Their usage has significantly increased in recent years due to the COVID-19 pandemic. In addition, quaternary ammonium compounds have replaced the recently banned disinfectants triclosan and triclocarban in consumer products. Quaternary ammonium compounds are found in daily antimicrobial and personal care products such as household disinfectants, mouthwash, and hair care products. Due to the pervasiveness of quaternary ammonium compounds in daily use products, humans are constantly exposed. However, little is known about the health effects of everyday quaternary ammonium compound exposure, particularly effects on human reproduction and development. Studies that investigate the harmful effects of quaternary ammonium compounds on reproduction are largely limited to high-dose studies, which may not be predictive of low-dose, daily exposure, especially as quaternary ammonium compounds may be endocrine-disrupting chemicals. This review analyzes recent studies on quaternary ammonium compound effects on reproductive health, identifies knowledge gaps, and recommends future directions in quaternary ammonium compound-related research. Summary Sentence  Quaternary ammonium compounds, a class of disinfecting compounds that have skyrocketed in usage during the COVID-19 pandemic, are emerging as reproductive and developmental toxicants.