The study was aimed at evaluating microbial contamination on the premises of the sewage treatment plant by determining the concentrations of selected groups of airborne microorganisms. Another objective was to determine the antibiotic sensitivity patterns of isolated strains of staphylococci. The research was conducted in a seasonal cycle, by the impaction method using Merck MAS-100 air sampler. Samples were collected at six sites, each representing a different stage of sewage treatment. The susceptibility of isolated staphylococci was assessed with the disc-diffusion method, following the recommendations of the EUCAST. The results indicate that the microbial population in the air of the investigated area was dominated by mold fungi, whose highest average concentration was recorded at site IV located near the final clarifier (7672 CFU•m-3). Heterotrophic bacteria and mannitol-positive staphylococci were the most numerous at locations where sewage undergoes primary treatment. In each subseuqent stage the number of microorganisms emitted into the air from the sewage was lower. Antibiograms show that more than 50% of Staphylococcus spp. exhibited resistance to penicillin and 20% to rifampicin. In addition, 90% of the analyzed strains were sensitive to other antibiotics. The fungal community included the following genera: Cladosporium, Fusarium, Alternaria, Penicillium, Aspergillus, Aureobasidium, and Acremonium.The highest air contamination with all studied groups of microorganisms was recorded at the locations where mechanical sewage treatment was performed. During the subsequent stages lower numbers of heterotrophic bacteria were emitted into the air. The air in the investigated sewage treatment plant did not contain multidrug-resistant staphylococci.
The aim of this research was to evaluate the microbiological indoor air contamination level in chosen facilities of the primary health-care for adults and children. The total numbers of mesophilic bacteria, staphylococci, coli-group bacteria and moulds in both surgery rooms and patients’ waiting rooms were determined. Air samples were collected with a MAS 100 impactor and the concentration of microorganisms was estimated by a culture method. The microbiological air contamination level was diverse: the number of mesophilic bacteria ranged from 320 to 560 CFU/m3, number of staphylococci - 10-305 CFU/m3, coli group bacteria - 0-15 CFU/m3 and moulds - 15-35 CFU/m3. The bacteriological contamination level of the air in examined community health centers was higher than described in the literature for hospitals and exceeded the acceptable values proposed for the surgery objects.
The aim of the research was to determine the microbiological quality of atmospheric air in the Tuchów Sewage Treatment Plant, based on the presence of mesophilic bacteria, α- and β-hemolytic bacteria, actinomycetes and fungi. Bioaerosol measurements were made at four points (raw sewage inlet, aeration chamber, puriﬁ ed sewage outlet and 150 m from the treatment plant, at the background point) in the period from January to December 2018. Bioaerosol samples were collected using Andersen’s 6-stage cascade impactor. The tested atmospheric air was characterized by a qualitatively and quantitatively diverse microﬂ ora. The highest amounts of all the studied groups of microorganisms were found at the raw sewage inlet, and in the case of actinomycetes, also twice in the place of biological puriﬁcation. However, there were analyzes in which a higher concentration of microorganisms was observed outside the treatment plant at the control point constituting the background. This applies to bacteria and fungi. The largest source of emission of microorganisms to the atmosphere was the mechanical part of the sewage treatment plant (raw sewage inlet). The tested treatment plant may therefore contribute to the deterioration of the quality of the atmospheric air.