Something that most people have never heard of, Toilet plume was found to be the way that SARS coronavirus spread rapidly in a Hong Kong apartment complex in 2003. Toilet Plume is the aerosolized droplets that are produced when a toilet is flushed. It turns out, toilet plume can possibly be the hidden spreader of Covid-19. All people should immediately keep their toilet lids closed when not in use and sanitize the seat prior to each use. They should also close the lid before flushing. It is best to avoid all public toilets because they most likely do not have lids. The vast majority of commercial public toilets are the pressure-assisted type that produce an even larger amount of fine aerosol plume, which can contain air-borne virus particles therefore infecting the next user. Toilet manufacturers should be urged to come forward with any internal research they have already conducted on toilet plume to analyze if there are any methods that will help reduce the overall production of virus containing plume.
Here is a quote from one of the studies, Aerosol Generation by Modern Flush Toilets (emphasis added);
“The number of droplets appeared to increase with increasing flush energy, with statistically significant differences in droplet production across toilets. The FOM type toilet, which is ubiquitous in business, health care, and other public environments, produced far more droplets than the other toilets, both as total droplets and droplets per liter flushed.
All three modern toilets produced hundreds to thousands of droplet nuclei “bioaerosol” particles with each flush, though there were differences across toilets in droplet nuclei aerosol production as measured by mean airborne concentration produced. Aerosol production appeared to increase with increasing flush energy, in agreement with the droplet aerosol measurements immediately postflush. However, aerosol production was not proportional to preflush bowl water particle loading as would be expected for an assumed splash aerosolization model. An alternative bubble burst aerosolization mechanism is proposed that may be responsible for these results and similar results by other investigators.
There were also statistically significant differences in droplet nuclei production for different suspension particle sizes, with mean airborne concentrations decreasing as particle size increased. The mean air concentrations (or number of nuclei produced per flush) decreased with microsphere particle size.
These results provide additional support for concerns that flush toilets could play a role in airborne transmission of infectious disease via droplet nuclei bioaerosols. Further research is needed to separate the incidence of toilet flush aerosol-related airborne infectious disease transmission, if it exists as seems likely, from transmission by other routes.”
Another study on the SARS coronavirus outbreak in 2003 suggests that the size of coronavirus was ideal for it to become airborne from a toilet after being flushed. The following is a quote from this study, Lifting the lid on toilet plume aerosol: A literature review with suggestions for future research (emphasis added);
“Epidemiologic, experimental, and modeling studies of SARS are among the most compelling indicators of the potential for toilet plume to cause airborne disease transmission. A report on the 2003 SARS outbreak in Hong Kong’s Amoy Gardens apartment complex concluded that exposure and disease propagation was likely due to virus-laden aerosols originating in the sanitary system.64 The system was contaminated with SARS CoV when the index patient, who was suffering from diarrhea, visited one of the apartments and used the toilet. Sewer drain bioaerosol was believed to be drawn through dry floor drain U-tube traps into the bathrooms of other apartments by bathroom exhaust fans, and some may have then been exhausted to the outside of the multistory building and carried upward to other apartments. Prevailing winds were thought to be responsible for carrying the infectious aerosol to nearby buildings where cases also occurred.63,75 These studies suggest that SARS CoV droplet nuclei bioaerosols produced from contaminated sewage may have been highly infectious for significant periods and over long distances.“
As the Covid-19 virus spreads around the world, it is extremely urgent to alert medical professionals and public health officials to limit public restroom use or ban them altogether for the foreseeable future in areas with known Covid-19 outbreaks. Please inform your loved ones to leave the toilet lid closed unless they are using it (obviously) and to close the lid before flushing. It would also be wise to add a disinfecting tablet (like these Clorox “hockey pucks”) to the toilet bowl tank if you have a traditional gravity-flush toilet. This is not possible on pressure-assisted toilets because they do not have a tank which can be opened like gravity-flush toilet.
Another possible avenue of virus transmission suggested in the study is floor drain p-traps which have dried out in restrooms which allow virus containing aerosol to be transported to an adjacent restroom due to air turbulence or an exhaust fan. An easy way to fix this problem is to make sure all p-trap floor drains have water in them, ensuring a proper air seal.
Sources;
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4666014/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4692156/
Androids and Cavemen 