16S rRNA gene identification of airborne pathogenic bacteria isolated from bioaerosols of wastewater treatment plant

Background and objective Wastewater treatment plants (WWTPs) represent a source of airborne bacteria. The presence of airborne bacteria in the environment of WWTPs could be considered as a potential health hazard for the exposed workers. This study aimed to isolate and identify cultivable bacteria from bioaerosols of different sites in a WWTP using 16S rRNA gene identification, as a first step to identify the pathogenic health hazards among the exposed workers. Materials and methods Air samples were collected from various locations in a selected WWTP. Airborne microorganism samples were collected on the nutrient agar plates by the settle-plate technique and were identified by the 16S rRNA gene sequencing technique. Results A total of 32 bacterial isolates were collected and sequenced. The study identified 25 different bacterial species. Of the 25 different strains, 10 (40%) belonged to pathogenic bacteria. Overall, 40% of the isolated pathogenic species were from the secretary room locations. The isolated bacterial species were Staphylococcus sp. , Bacillus sp. , Rhodococcus sp. , Cellulosimicrobium funkei , Kytococcus sedentarius , and Kocuria rosea . The highest percentage occurrence was Bacillus sp. (37.5%), followed by Staphylococcus sp. (18.75%). Conclusions Disseminated infection can be associated with isolated pathogen, and this result gives a warning of the danger of the spread of pathogenic aerobic bacteria in WWTPs and their existence in indoor environments.