Contrary to previous study findings, closing the toilet lid before flushing doesn’t stop aerosolized viruses from contaminating bathroom surfaces, scientists from the University of Arizona and Reckitt Benckiser LLC, the company that makes the disinfectant used in the study, report in the American Journal of Infection Control.
The researchers added a bacteriophage (virus that targets and kills bacteria) to household and public toilet bowls as a proxy for human intestinal viruses. After they flushed the toilets (with the lid open or closed in case of the household toilets), they measured viral contamination of the toilet and bathroom floor and walls.
“Research has demonstrated that people with COVID-19, even those who are asymptomatic, excrete severe acute respiratory syndrome coronavirus (SARS-CoV-2) in fecal matter and other excretions,” the researchers wrote. “Viruses contaminating urine and feces can be aerosolized in building restrooms during toilet flushing.”
The resulting toilet aerosol plumes, they said, can land on surfaces more than 5 feet away.
My main concern is always my toothbrush. But it’s on a counter above the toilet. So wouldn’t keeping the lid down help significantly, in both the direction and distance of whatever is stirred up?
Turbulence might be enough bring it up and everywhere regardless. The movement of your own body would cycle air every which way right after you flush, plus many bathrooms have ventilation fans near the ceiling, drawing air upward.