Exposure to bioaerosols poses significant health risks to occupants of buildings, especially in tropical areas due to its climatic characteristics that favour airborne bacterial growth. This study investigated the levels and composition of indoor and outdoor airborne bacteria in residential buildings in Benin Metropolis. Air samples were collected from forty-five randomly selected houses across the five local government areas in Benin City using the passive sampling technique. The culture-dependent 16S rRNA gene technique was utilized in theidentification of the bacterial isolates. The results revealed that the mean concentrations of the indoor and 3 3 outdoor total bacteria varied from 476.1 to 939.3 CFU/m3 and 181.1 to 373.2 CFU/m3 in the wet season, 335.0 3 3 to 457.2 CFU/m3 and 387.2 to 627.8 CFU/m3 in the dry season, respectively. The concentration of indoor and outdoor airborne bacteria varied significantly (P=0.001) during the wet and dry seasons. Basic Local Alignment Search Tool homology showed that the 16S rRNA gene sequences of isolates were related to Proteus mirabilis, Pectobacterium brasiliense, and Enterobacter sichuanensis. The bacterial communities identified are associated with humans and other outdoor environmental media and could lead to critical health outcomes among exposed vulnerable occupants of the buildings. This study, therefore, provides a database for airborne bacteria in residential houses in the study area and could assist in the implementation of effective interventions that reduce the risks and provide a safe environment.

Soil contamination from pharmaceuticals is an evolving issue, consequently measurable data on their microbial effects are deficient. Thus, this study investigated the effects of pharmaceutical effluents on soil microbiome and the physicochemical parameters of soil samples obtained from Ugbowo, Benin City, Nigeria using standard procedures. The experiment which lasted for four weeks consists of four treatments of soil samples with pharmaceutical effluents of different percentages and one soil sample without pharmaceutical effluents (control). These include: soil treated with 250 ml of pharmaceutical effluents (25%); soil treated with 500 ml of pharmaceutical effluents (50%); soil treated with 750 ml of pharmaceutical effluents (75%), soil treated with 1000 ml of pharmaceutical effluents (100%) and soil treated without pharmaceutical effluents (0%). There was significant increase in the soil microbial counts in all effluent treatments compared to the control soil. A total of 16 isolates were identified. Ten were isolates belonging to the genera Bacillus, Arthrobacter, Proteus, Pseudomonas, Staphylococcus, Escherichia, Klebsiella, Enterobacter, Streptococcus, and Chromobacterium, while Fusarium sp., Mucor sp., Saccharomyces sp., Aspergillus niger, Rhizopus sp. and Penicillium sp. were the observed fungal isolates. The mean values of the soil physicochemical properties were all significantly higher in the treated groups compared to the control. This study revealed that pharmaceutical effluents altered the soil microbiological and physicochemical properties. The possibility of these alterations was due to the high nutrient content of the effluent which enriched the soil with additional nutrients needed for microbial growth.