Unews World
Public bathroom hand dryers, often seen as an eco-friendly and convenient alternative to paper towels, may be doing more harm than good. Biologists and health experts warn that these devices can blow bacteria and pathogens back onto freshly washed hands, undermining hygiene. Laura Gonzalez, a biologist who shares science-backed tips online, recently cautioned that powerful jet dryers pull in contaminated air from toilet flush aerosols and redistribute it. Her warning aligns with several scientific studies showing that air dryers not only spread germs onto hands but also contaminate the restroom environment.
How hand dryers spread bacteria and pathogens
Studies from the University of Connecticut and Quinnipiac University demonstrated that when petri dishes were exposed to bathroom air with dryers running, up to 254 bacterial colonies grew—compared to almost none when dryers were off. The majority of bacteria originated from toilet aerosols circulating in the air. High-speed jet dryers amplify the risk, projecting contaminated particles onto hands, clothes, and nearby surfaces, leaving users more exposed to harmful microbes.
Scientific evidence against hot-air and jet dryers
Multiple peer-reviewed studies have reinforced these findings. A 2018 study by the American Society for Microbiology revealed that hot-air dryers emit contaminated airflows carrying spores and pathogens. Even when fitted with HEPA filters, dryers still released bacteria, suggesting they cannot fully eliminate the risk. Research published in Infection Control & Hospital Epidemiology similarly showed that jet dryers disperse germs further than traditional drying methods, with droplets spreading metres away and lingering in the air.
Why paper towels are safer
Comparative research, including findings published in Mayo Clinic Proceedings, confirmed that paper towels are more effective at physically removing bacteria during the drying process. Unlike dryers, paper towels do not propel germs across restrooms. They also offer practical hygiene advantages—users can employ them to turn off taps or open restroom doors, minimising contact with contaminated surfaces.
Health guidelines support paper towels
Health authorities such as the World Health Organization recommend paper towels as the most hygienic drying option. They rapidly absorb moisture, reduce microbial transfer, and prevent the environmental contamination associated with air dryers. For high-traffic settings like airports, schools, and hospitals, adopting paper towels can significantly lower infection risks compared to jet air dryers.While public hand dryers may save trees and reduce paper waste, they also pose a hidden threat by spreading bacteria and pathogens. For safer hygiene, experts stress that using paper towels remains the most effective way to dry hands after washing. In environments where public health is a priority, steering clear of hand dryers could make all the difference in preventing disease transmission.
