Invisible Cohabitants: Investigating the Microbial Presence in the Kitchen Sponges of Maastricht

  • Sara Jovanovska
  • Lucy Quirant
  • Davor Davidovikj
  • Herman E. Popeijus


This study examines the correlation between the presence of bacteria in kitchen sponges of Maastricht students and the number of sponge users. Participants from 34 households were given a new kitchen sponge that they used for seven days. The samples were examined by performing a standard plate count on blood agar plates to approximate the number of colonies present on each sponge. Linear regression was performed using a 5% statistical significance. The number of bacteria per sponge was on average the same, indicating that the number of bacteria associated per person is smaller in larger households. Statistically significant correlations were observed between the amount of bacteria and variables such as dietary preference and gender. Keywords: sponges, house inhabitants, Maastricht, students, bacteria.