# Toothbrush contamination by toilet plumes: A comparative study in Chennai, India

## TL;DR

Toothbrushes can get contaminated with harmful microbes from toilet plumes, posing a risk to oral and overall health.

## Contribution

This study compares microbial contamination of toothbrushes stored in different bathroom environments in Chennai.

## Key findings

- All four tested pathogens were found on toothbrushes stored in various environments.
- Candida was identified by budding yeast appearance and Enterococcus by a negative catalase test.
- Toothbrush bristles support microbial survival, risking oral and systemic health.

## Abstract

Oral health is vital to overall wellness, yet toothbrushes can harbor harmful microorganisms, especially in compromised individuals.
Contamination occurs when microbes survive on surfaces such as "toilet plume" where bio-aerosols are released during flushing. Therefore,
it is of interest to assess the microbial contamination of toothbrushes with and without lids, stored in different environments over a
period of two months. Hence, we used data from equal student groups who used toothbrushes stored inside or outside bathrooms for this
study. Samples from 36 used brushes were tested for Candida albicans, Escherichia coli,
Pseudomonas aeruginosa and Enterococcus faecalis using nutrient agar, MacConkey agar and biochemical
tests like IMViC and TSI. Results confirmed all four pathogens across samples, with Candida identified by budding yeast
appearance and Enterococcus by a negative catalase test. These findings show that toothbrush bristles support microbial
survival, which can negatively impact oral and systemic health. Thus, proper storage and regular disinfection are essential to reduce
infection risk so as to maintain oral hygiene.