Waste composition and identification of Bacteria in waste generated from a tertiary hospital in Southwestern Nigeria

Improper treatment of hospital wastes is currently attracting considerable attention due to their infectious and hazardous nature. This study assessed the generation, composition, isolation and identification of bacteria in waste from a tertiary hospital in Abeokuta, Southwestern Nigeria. The quantity of waste generated daily in the hospital was determined for 4 months (2 months each in wet and dry seasons). The wastes were later segregated and categorized into general, infectious, highly infectious, pharmaceutical, pathological, chemical and sharp waste in line with the World Health Organization specifications. Samples of hospital wastes from six selected sections within the hospital were collected and subjected to microbiological examinations. The microorganisms isolated from the waste were identified using deoxyribonucleic acid (DNA) extraction and sequencing. The total quantity of waste generated in the hospital during the study period was 13,101.32 kg (6894.92 and 6206.40 kg for wet and dry seasons, respectively). The waste generated per day was 106.51 kg, whereas the quantity of waste generated per bed per day and the quantity of waste generated per patient per day were 0.35 and 0.24 kg, respectively. The DNA extraction and sequencing confirmed the presence of Alcaligenes faecalis, Lysinibacillus fusiformis, Pseudomonas aeruginosa and Bacillus thuringiensis in the hospital waste. Wastes generated in the hospital were hazardous, and physical composition and classification of the medical waste did not vary with season.