Abstract:
Nowadays people spend their time more indoor than outdoor. Their activity makes them
exposed to many environmental pollutants that affect their health. The microbes are normally
present in both indoor and outdoor environments. Bioaerosols are associated with these dust
events and can promote infectious diseases, allergy, asthma, and neurological diseases among
vulnerable populations. The aim of this study was to investigate the total concentration of
indoor-outdoor relationship of airborne bacteria and fungi, to find the indoor/outdoor ratio in
the selected area of Upper Silesian, Poland. The study was conducted in Gliwice a typical
city of upper Silesian, Poland. The measurement was done using Anderson six stage with
aerodynamic diameter ranges for each stage is > 7µm, 7 - 4.7 µm, 4.7 - 3.3µm, 3.3-2.1µm,
2.1-1.1 µm, and 1.1- 0.65 µm with air flow latest 28.83 l/min for 10 minutes.
The highest median concentration value of bacterial measured in indoors of the locker room
was (4802 CFU/m3
) and the lowest concentration level in the classroom was (2943 CFU/m3
).
Comparing with the outdoor air (median: 261 CFU/m3
); the indoor air concentration was
three times higher than the outdoor bacteria. The highest fungi levels concentration was
(median: 491 CFU/m3
) in the corridor. The lowest fungi level concentration was observed in
both locker room (median: 300 CFU/m3
) and in classroom (median: 276 CFU/m3
).
The indoor/outdoor ratios of bacterial and fungal concentrations was (1.2 min and 78.1 max)
and (0.3 min and 1.6 max) in the primary school respectively. Size distribution bacterial
aerosol distribution is unimodal. In indoor the peak appeared at stage 4 (2.1 – 3.3 µm) and
5(1.1 – 2.1 µm). Species of airborne gram-positive bacteria was the most abundant and it was
95.5%. Identified species are Micrococcus spp, Staphylococcus spp, Bacillus spp,
Corynebacterium spp, Pseudomonas spp.
