ABSTRACT
Indoor and outdoor air quality is the air parameters that are found in building, business, school and home environment. The source of contamination can vary they can be biological resources or chemical resources. This study aimed at isolating airborne bacteria from University of Benin hostel environments.
Using the settle plate method, the samples were collected from Hall 1, Hall2, Hall3, Hall4, Hall5 male and Female and NDDC male and Female hostels general bathrooms by exposing prepared Nutrient Agar, McConkey Agar, Eosine-methylene Blue and Salmonella Shigella Agar plates for 10 minutes at 1.5 meters above ground level then taken to the microbiology laboratory for analysis. Culture media were prepared according to the manufacturer’s instructions. Antibiotic sensitivity was done using disc diffusion method.
The mean concentration of the airborne bacteria load in outdoor environment ranged from 3.3±0.33 cfu/m3 to 33.3±16.8 cfu/m3 while outdoor bacterial count ranged from 11.0±3.78 cfu/m3 to 159±80.0 cfu/m3. Indoor and outdoor air samples from all the hostels were not significantly different (p>0.05). Bacteria isolated were Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica and Bacillus spp. Staphylococcus aureus was the most occurring bacterial isolate (30.8%) while Pseudomonas aeruginosa was the least occurring bacterial isolate (7.69%). Bacillus spp. and S. aureus were susceptible to zinnacef, amoxicillin, ciprofloxacin and erythromycin and resistant to pefloxacin. P. aeruginosa, Salmonella enterica and E. coli were resistant to pefloxacin and chloramphenicol and susceptible to gentamycin, sparfloxacin and ciprofloxacin. P. aeruginosashowed highest level of resistance with multiple resistance index of 0.5 while Salmonella enterica showed least level of resistance with multiple resistance of 0.2. It is important to monitor indoor and outdoor air in bathrooms most especially the public bathrooms as most microorganisms isolated showed high level of resistance to conventional antibiotics.
