Mold can grow in sink drains because of the fungi that live there, which serve as “reservoirs”

Photo by ato de on

According to studies conducted at the University of Reading, a remarkable variety of fungi can be found in sinks and P-traps.

Five University of Reading undergraduate students, including a Ph.D. student, examined more than 250 restroom sinks for fungi, such as black molds, and cousins of baker’s yeast. Each of the sinks exhibited a remarkably similar population of yeasts and molds, demonstrating that sinks in use in public places share a role as reservoirs of fungal species.

The research are presented in Environmental DNA.

The study was headed by Dr. Soon Gweon. He stated that they spend 90% of their time indoors thus they are exposed to fungi in their homes and offices. For most people, this isn’t a concern, but for those who are immunocompromised, specific fungus species can cause significant infections.

It’s not a big surprise to locate fungi in a warm, damp climate. But sinks and P-traps have thus far been disregarded as possible collectors of these micro-organisms. This could be a really important result for individuals who are trying to help vulnerable people avoid illnesses by some of the opportunistic pathogens that may be lingering in sinks, like Fusarium.

The method the students utilized identify species provided them the wider families depicted. Further investigations will investigate in detail at precisely which species are prevalent and will discover probable disease-causing fungus.

Zoe Withey, the University of Reading Ph.D. student participating in the study, said that it has been excellent to provide undergraduate students an actual hands-on training of environmental microbiology. And the fact that they found intriguing results, deserving of a peer-reviewed publication, is an experience where many students won’t have until their Ph.D. studies.

The varieties of fungi that thrive in sinks can resist high temperatures, low pH (acidic), and poor nutrition. Some will even consume detergents, found in soap, as a source of carbon-rich diet.

There was zero differentiation between the sexes when it came to the quality of the facilities. In fact, the fungus population in each of the 250 sinks that were examined was remarkably consistent.

Dr. Gweon said that were they in a hospital or nursing home, where there are many people with impaired immune systems, these results could indicate a major threat to their health.

The researchers would like to see cleaning techniques established that can handle the colonization of sinks and P-traps, particularly in circumstances where many individuals may use a single sink.


Zoe Withey et al. Mycobial community assemblages in sink drains across a university campus, Environmental DNA (2022). DOI: 10.1002/edn3.375