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

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 <i>Candida albicans</i>, <i>Escherichia coli</i>, <i>Pseudomonas aeruginosa</i> and <i>Enterococcus faecalis</i> using nutrient agar, MacConkey agar and biochemical tests like IMViC and TSI. Results confirmed all four pathogens across samples, with <i>Candida</i> identified by budding yeast appearance and <i>Enterococcus</i> 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.