The Hidden Threat : Unveiling the Microbial World in the Washroom

We spend 90% of our time indoors, be it a home, workplace, education centres, places of worship or
gyms. Indoor air quality is a global issue, both short- and long-term exposure to indoor air
pollution can cause a range of health issues, including respiratory diseases, heart disease, cognitive
deficits, and cancer. According to the WHO globally 3.8 million people die every year due to illness
attributed to indoor air.
The global emphasis on Indoor air quality (IAQ) is generally directed towards workspaces and
homes, and oddly enough, the one area that is frequently overlooked is the washroom. This
seemingly mundane space dedicated to hygiene holds within it confines a complex microbial
ecosystem that poses significant health risks, impacting both the well-being of the individual and
the overall hygiene of the space in and around this area.

The Bio-Aerosol Threat
Studies have revealed that each time the toilet bowl is flushed it releases bio-aerosols, which
include viruses, bacteria, and microscopic faecal matter. Basically we are breathing in toilet water
and whatever is in it. These bio-aerosols linger, spread, and also settle on surfaces in the washroom-
bathroom area, contributing to potential and on-going transmission. Larger bio-aerosols settle on

surfaces, creating fomite transmission. A fomite is an inanimate object, which is likely to carry
infection, and unknown to us, countertops, faucets, or door handles, are the fomite transmitters!
Once contaminated, the high-touch areas like door handles and faucets, act as conduits and
innocuously transfer their ‘storehouse’ of infections, having become breeding grounds for bacteria,
viruses, and pathogens, to us! We then provide the further breeding and spreading grounds within
our systems to these eager and ready-to-attack invaders! A study conducted by the University of
Colorado Boulder in 2023, showed exactly what happens each time we flush the toilet.
Common Microbial Residents in Washrooms

Courtesy : University of Colorado Boulder

If this sounds far-fetched and an over-the-top dramatisation we just need to review the kind of
invaders waiting to attack!
The main culprits are a cocktail of bacteria and viruses! E.coli, Salmonella, Staph, and a variety of
viruses… all affect us in various ways, but the fact that they find a very friendly breeding space in
washrooms is possibly what we are not too aware about.
Interestingly, E. coli, is a type of bacteria which is naturally found in human and animal intestines.
Most strains of E. coli are in fact harmless and play a crucial role in the digestion process. But a
couple of rogue strains can and do cause illnesses. These strains are usually associated with faecal
contamination. E.coli has the capacity to replicate every 20 minutes, which means that in less than 8
hours a single cell can become over 8 million cells. These strains of the bacterium have the capacity
to spread rampantly and have stubborn and unbelievable longevity to stay and spread in the host. It
is can be found on toilet surfaces, and on door and faucet handles. Inadequate and careless hygiene
in cleaning hands or unclean surface areas contribute to the spread of E. coli infections.
There is a plethora of bacteria and viruses that populate the environment as thickly perhaps as we
humans do! Just to name a few — Salmonella, a bacterium known for causing food-borne illnesses;
Staph or Staphylococcus aureus often found on the skin and in the nasal passages. We can be
carriers without being affected but we can transmit the mild to very severe conditions to others who
are more susceptible. Viruses galore accompany us on a daily basis! The influenza virus, is
responsible for the seasonal flu outbreaks; Norovirus is a highly contagious and causes
gastroenteritis;. Rhinovirus, is the most common cause of the common cold; Adenovirus can cause
respiratory and gastrointestinal infections; and the Pneumonia virus, is contagious airborne virus
that can cause severe respiratory issues; finally of course the crowning glory is Covid and its
variants!
Whatever be the common means of their spread, be it contaminated food and water, or body-to-
body, person-to-person, the unclean surfaces such as sinks and door handles and close-circuited air
in washrooms, can serve as reservoirs for all of them. Washrooms, particularly public ones, which
are frequented by countless human beings and where hygiene is more likely to be compromised,
provide the environment because these bacteria and viruses have the ability to survive on surfaces
for varying extended periods, especially where the frequency and convenience of transmission is
high.
In addition to the continuous reproduction of bacteria and viruses are the harmful gases and
compounds VOCs (Volatile organic compounds that are found in indoor spaces including the
washrooms. They are released from cleaning agents, air fresheners, personal care products paint,
varnish, furniture and several other products. They are volatile, as the vaporise easily and rapidly,
leading to respiratory irritation, headaches, and prolonged exposure to the VOCs have long-term
side effects.
Additionally the high humidity and moisture content in the washroom creates an ideal breeding
rough mould and mildew. The pores released by the fungi rapidly get absorbed in the air and have
know to act as triggers for respiratory issues i.e. asthma and other allergies
Most washrooms do not have adequate ventilation, the extractors if any are designed to
predominantly focused on odour removal. The lack of or inadequate ventilation reduces proper air
circulation and add to the existing contaminated air, CO2 and PM (particulate matter).
CO2 is not only produced by us humans, in fact it is bacteria and aerosol based cleaning agents and
air fresheners that generate a high volume of CO2. which combines with the PM generated by toilet
flushing, hand drying methods and aerosolised cleaning agents.

Health Risks

All of this convert this dedicated space for hygiene into a playing field of harmfully contaminated
creating multiple health risks for us, be it respiratory issues, like asthma COPD (Chromic

obstructive pulmonary disease) to allergies, sensitive and other infections and illnesses, with the
most common symptoms being fatigue and headaches .
Coming in contact with bacteria such as E. coli, Staph, Salmonella, and norovirus, all of which
could be present on toilet and washroom surfaces, can contribute to urinary tract infections (UT),
skin infection and other gastrointestinal infections, like diarrhoea, vomiting, and stomach cramps
respectively.
The long term exposure to harmful air in washrooms may contribute to long-term health effects,
including respiratory diseases, cardiovascular issues, and a compromised immune system.
Mitigating the Risks
Standard practices of washroom cleanliness, along with touch-less fixtures, and extractors is not
enough. Just by regular or frequent clearing of the surfaces with chemical laden cleaning agents is
not enough. Washroom fresheners work as masking agents and are just cosmetic.
There are multiply ways in which we can mitigates these risks and effectively reduce the
contaminates with the washrooms. Just regular cleaning with chemical laden cleaning agents does
not cut it. Often the material used, like mops and cleaning cloths are not sterilised, and are at times
are used outside the washroom in other parts of the indoors space, which expands the spread of the
contaminates. Implementation of air and surface decontaminating systems and along with a
reduction in the use of chemical laden cleaning agents should be the first step.
Introducing public awareness, promoting hand hygiene and shutting the lid when you flush should
be second step. Ensuring that the is adequate soap and sanitisers in the washroom and encouraging
its use is important. Just washing ones hand with water will not cut it. Studies have shown that
shutting the lid before flushing reduces the bio-aerosols” from spread out and lingering in the air. If
possible, increasing the ventilation within the washroom, adds to reduction of the contaminates in
the air. However it does extract them out into the ambient air. Also the addition of touch less
fixtures along with promote proper disposal of waste, especially sanitary products, will add to
minimise the risk of bacterial contamination. Regular emptying of trash bins is essential to prevent
the proliferation of harmful microorganisms.

In conclusion

It is imperative to address harmful air in washrooms to safeguard the health and well-being of
occupants. Recognising the importance of IAQ in washrooms is a crucial step toward creating safer
and more sustainable indoor environments and the ESG protocols of any organisation
The battle against the hidden threat of microbial invaders in the washrooms, adopting proactive
strategies, along with promoting public awareness, we can create safeguards to protect the health
and well-being of occupants. It being with education, awareness, and a commitment to adopting
practices that prioritise hygiene in these essential spaces.
The simplest and most important thing for each one of us to do is to “Trust Your Nose”. If the
washroom smells bad, wait to let the room air out a bit before you go in.