Hi-tech hand dryers could facilitate the spread of pathogens in restrooms by sending germs and bacteria flying through the air.
Despite the rising popularity of jet hand dryers in public restrooms due to the widespread perception that they're more hygienic, the devices could in fact be far less sanitary than the traditional paper towel dispenser.
A new study claims that hand dryers of all types - including the latest, hi-tech models that employ heated air jets, actually propagate germs and bacteria at a far greater rate than the humble paper towel.
The study led by Professor Mark Wilcox from the University of Leeds concluded that jet hand dryers spread 27 more bacteria and microbes than paper towels, as well as four times as many as standard hand driers.
The team of researchers tested the volume of microbes spread by the devices by having study participants wear gloves laden with lactobacilli - a form of benign bacteria found in yoghurt.
The participants then dried their hands using the jet air dryer, the standard hand dry or a paper towel, while scientists measured airborne spread of microbes - a critical channel of pathogen transmission in a bathroom environment, given the confined nature of the space and relatively close proximity of occupants.
"Next time you dry your hands in a public toilet using an electric hand dryer, you may be spreading bacteria without knowing it," said Wilcox. "You may also be splattered with bugs from other people's hands.
"These findings are important for understanding the ways in which bacteria spread, with the potential to transmit illness and disease."
While the study has been published in the Journal of Hospital Infection, its conclusions should perhaps be taken with a grain of salt, given that funding was provided by the European Tissue Symposium - an industry group that includes paper towel manufacturers amongst its members.
The study also confined its focus to the airborne spread of microbes, and refrained from assessing the actual hygiene of hands after drying.