A new study from the University of Waterloo shows that common disinfectants currently in use could be made safer with the simple application of ultraviolet light. Over 400 disinfectants with benzalkonium chloride (BAK) as an active ingredient are regularly used in households, healthcare facilities and food processing plants to protect against a wide variety of viruses and bacteria. BAK’s high toxicity means it cannot be used in high concentrations, and products containing the chemical are harmful to humans and the environment. But BAK is an essential ingredient for disinfectants efficacy.
In the study, researchers found that a disinfecting procedure using BAK followed by ultraviolet radiation minimized the harmful effect of the chemical’s residue on humans. After exposing a solution containing BAK to germicidal UVC lamps, researchers applied the solution to cultured human corneal cells for 5 minutes. They analyzed the cells for metabolic activity and viability and found that the solution was completely neutralized by UVC, causing no harm to the cultured cells.
‘“With concerns about the spread of COVID-19, people are utilizing products with BAK as an active ingredient more than ever,” said Waterloo alumnus and lead author Manlong Xu, who is currently a clinical research fellow at the University of Alberta. “For many industries, there is the demand to improve the efficacy of standard disinfection procedures, while also keeping in mind any potential negative impact on the environment.”’
The study, “Neutralization of the eye and skin irritant benzalkonium chloride using UVC radiation,” was published in the journal Cutaneous and Ocular Toxicology.
Credit: University of Waterloo