Quaternary ammonium compounds have been widely used as disinfectants for decades. But some scientists think we need more data on their safety in people
With the COVID-19 pandemic raging around the globe, many people are depending on disinfectants, hand sanitizers, and sanitizing wipes to keep the novel coronavirus at bay. Such products often contain quaternary ammonium compounds, or quats. These workhorses of modern disinfection have been found in consumer products for decades. But in the last 10 years, scientists have linked quats to reproductive and developmental problems in animals, and found they can disrupt key cellular processes. So far there’s no data linking the compounds to toxicity in humans, but some scientists say there’s more to be done to fully assess quats’ safety.
At first glance, the 10-days-old mouse embryo looked like any other. A closer look into the microscope, though, told Terry Hrubec something was wrong. The embryo’s neural tube—what would become the mouse’s brain and spinal cord—had a tiny gap. It had not closed fully
It was January 2009, and Hrubec, a reproductive and developmental toxicologist at Virginia Tech and Edward Via College of Osteopathic Medicine, was researching how to prevent such neural tube defects. She expected to see them in embryos from her test group of pregnant mice exposed to drugs known to cause the defects. This embryo, however, came from her control group of healthy, unexposed mice. In all, Hrubec would find neural tube defects in 10% of the control embryos.So, Hrubec repeated the experiment to make sure she hadn’t mixed up her mice or embryos. But she got the same results. Puzzled, she approached the laboratory staff who took care of the animals.No, the mice hadn’t come from anywhere new. No, their diet hadn’t changed. Yes, their food and bedding were pathogen-free.
Finally, Hrubec asked the supervisor of the animal facility at Virginia Tech if they had made any changes at all recently.It turned out there was one: a new disinfectant. To prevent disease among the animals, the animal care staff would typically foam the floors, walls, and racks weekly, and mop the floors daily. The staff had been using a chlorine-based disinfectant.
But sometime during the fall of 2008, the staff switched to one containing a mixture of alkyldimethylbenzylammonium chloride (ADBAC) and didecyldimethylammonium chloride (DDAC). These compounds, which belong to a family of molecules called quaternary ammoniums, or quats, have long appeared in consumer products.Through further research, Hrubec has linked ADBAC and DDAC exposure to developmental and fertility problems in mice. Separately, other scientists have found quats can exert negative effects on cellular processes.
Now, as COVID-19 grips the globe, researchers are worried not only about the novel coronavirus SARS-CoV-2, but also the disinfectants used to destroy it on surfaces.