Quantitative and qualitative analysis of bioaerosols emissions from the domestic eastern wastewater treatment plant, Alexandria, Egypt

Bioaerosol studies showed that wastewater treatment plants (WWTPs) are a significant source of bioaerosol emissions. In this study, 170 samples of total bacteria, total coliform, and total fungi were collected from 10 sites within a domestic WWTP, Alexandria, Egypt, using the sedimentation technique. According to the Index of Microbial Air Contamination (IMA) classes, the total bacteria range was 108–5120 CFU/dm 2 /hour, and all samples were classified as “very poor” except one sample of an office, which was classified as “poor.” The total coliform range was 0–565 CFU/dm 2 /hour, and 6 samples were classified as “very poor,” while one sample was classified as “poor.” The total fungi range was 0–209 CFU/dm 2 /hour, and 9 samples were classified as “very poor,” while 4 samples were classified as “poor.” After the conversion to CFU/m 3 , the counts of total bacteria, total coliforms, and total fungi were 897 − 42.7 × 10 3 , 0–4.71 × 10 3 , and 0–2.69 × 10 3 CFU/m 3 , respectively. Several identified bioaerosols have been reported before as a cause of human infections. They included Lysinibacillus fusiformis , Bacillus cereus , Alcaligenes faecalis , Klebsiella sp., Escherichia coli , Aspergillus spp., Penicillium spp., Rhizopus sp., Candida sp., and Rhodotorula sp. These results indicated an increased health risk to WWTP staff, which needs more attention and more efficient control measures.