EVALUATION OF INDOOR AND OUTDOOR AIR QUALITY IN SELECTED OFFICES AND LABORATORIES IN UNIVERSITY OF CALABAR

*Tiku D. R., Bassey I. U. and Asikong E. B. E.

ABSTRACT

The study to evaluate the indoor and outdoor air quality in selected offices and laboratories in the University of Calabar was carried out. Laboratories in faculty of biological sciences (MCB LAB 222, GBT LAB, ZEB LAB) and selected offices within faculty of physical sciences (OFPS1, OFPS2) and Department of Microbiology (OMD1 OMD2), as well as the open car park in Biological Science (CPBB) were examined for microbial load. The sedimentation technique using open Petri-dishes containing Nutrient agar, Manitol salt agar, MacConkey agar, and Sabouraud dextrose agar placed one meter above the floor for 15 minutes at different sections of the aforementioned sampling sites was used. They were transported to the Department of Microbiology laboratory in a clean container for analysis. Bacterial isolates from the samples were identified using standard microbiological techniques while fungal isolates were identified based on colony appearance, microscopic examination of spores and hyphal characteristics of lactophenol cotton blue preparation. Results obtained in this study revealed that air samples collected from MCB LAB 222 had the highest total heterotrophic count (184±6.08cfu/m3), total Staphylococcal count (20±2.83cfu/m3) and fungal count (23±2.33cfu/m3), while air samples collected from an office in faculty of Physical Science (OFPS1) had the least total heterotrophic count (38±2.32cfu/m3), total Staphylococcal count (3±0.08cfu/m3), total coliform count (0cfu/m3) and total fungal count 4±0.08cfu/m3). Bacterial species isolated from the air samples were identified as Bacillus sp., Staphylococcus aureus, Pseudomonas sp., Escherichia coli, Streptococcus sp., and Micrococcus sp., while the fungi species was identified as Aspergillus sp., Mucor sp., Penicillium sp., and Fusarium sp. Amongst the bacteria isolates, Staphylococcus aureus had the highest frequency of occurrence (39) while for the fungi isolates, Fusarium sp had the highest frequency of occurrence (15). However, this study has revealed that the indoor air quality of the laboratories was not hygienic and exceeded the WHO standard of 100cfu/m3 for indoor air. Furthermore, the levels and type of airborne microorganisms identified in the air samples are capable of causing severe infections to occupants and visitors who have more severe impairment of immunity. Hence, improving hygienic practices as well as ventilation performance may be a viable solution to overcome this risk.

Keywords: The study to evaluate overcome this risk.