Assessment of Microbiological Air Quality in University Hostels: A Comparative Study of Male and Female Hostels

Indoor air quality (IAQ) is vital to environmental health, especially in high-density living spaces like university hostels. This study assessed the microbiological air quality in male and female hostels at Wellspring University, Benin City. Air sampling was conducted in eight hostels using the settle plate method. Four rooms per hostel were randomly selected, and nutrient agar and MacConkey agar plates were exposed for 10 minutes to collect airborne microorganisms. Colonies were subcultured, and isolates identified through standard biochemical and microscopic techniques. Additional IAQ parameters such as particulate matter (PM2.5 and PM10), total volatile organic compounds (TVOCs), humidity, and temperature were also monitored. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method on Mueller-Hinton agar, and multiple antibiotic resistance (MAR) indices were calculated. M4 and F2 hostels recorded the highest bacterial load (78 CFU/m³), while F3 hostel had the lowest (1 CFU/m³). Staphylococcus aureus (27.39%) was the most prevalent isolate, followed by Escherichia coli (22.82%), Pseudomonas aeruginosa (20.12%), Enterococcus faecalis (17.66%), and Bacillus subtilis (12.01%). S. aureus was resistant to ofloxacin, while B. subtilis showed resistance to 5 of 12 antibiotics. MAR indices indicated high-risk levels for most isolates except S. aureus. Air quality monitoring revealed that PM2.5, PM10, and TVOC levels in M1–M4 hostels exceeded WHO limits, while temperature and humidity were slightly above recommended values. The study highlights significant microbial and air quality differences between male and female hostels, underscoring the need for improved hygiene and ventilation strategies in shared accommodations.