Indoor Air Quality of Selected Lecture Theatres in Faculty of Life Sciences, University of Benin

Abstract

The presence of airborne microbes can be detrimental to mankind. Research on bacteriological pollution of indoor air in selected lecture theatres of Life Sciences Faculty, University of Benin, was carried out. Surveys were conducted in the period of July-September, 2019. Microbiology lecture Theatre, Environmental Management and Toxicology Lecture Theatre, Animal and Environmental Biology (200 Level) Laboratory, Microbiology (400 level) Laboratory, Plant Biology and Biotechnology (200 level) Laboratory and Microbiology Postgraduate Laboratory were the sampling areas. Air samples were obtained using passive sedimentation method (settle plate method). Visible colonies were expressed in colony forming units per meter cube (cfu/m3) and pure discrete colonies were enumerated and characterized. Bacteria counts ranged from 1.83 + 0.35 – 18.34 + 2.83 (x102 cfu/m3) in July 2019. In August 2019, Bacteria counts ranged from 3.14 + 0.71 –33.27 + 65 (x102 cfu/m3). In September 2019, values ranged from 3.67 + 0.71 – 29.60+ 6.01 (x102 cfu/m3). The evaluation of air quality in the designated sampling points based on the sanitary standards formulated by the European commission revealed that 8 of the sampling points showed high level of pollution (44.44%) and 4 sampling points had very high level of contamination (22.33%). Three bacterial isolates were identified as Staphylococcus epidermis, Staphylococcus aureus and Bacillus cereus and they are of public health importance. High influx of students, architectural design of rooms and systems of ventilation are factors that can influence the indoor airborne bacterial population.