Indoor-outdoor relationship for airborne bacteria, fungi and particles in the selected area in upper silesia, poland

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.