This study aimed to evaluate the effect of land use on hospital bioaerosols and determine the effective radius. The concentration of fungi and bacteria in indoor and outdoor air was determined by the 0800NIOSH. Then land uses were determined by Google earth within a range of 0.5-5 km around three hospitals. Data were analyzed by using Spearman correlation, and a t test was used to determine differences between groups. Data were recorded in Excel and entered into Matlab2018 for analysis. The results of the study showed that the concentration of fungi and bacteria was higher in the indoor and outdoor hospital B (bacteria = 343-43, fungi = 106-291 CFU/m3) (P = 0.04). Maximum land use was also found in hospitals A and B related to urban and bare, while in hospital C, they were urban and bare. Mathematical modeling has shown that the trend of land-use variation over different radii consisted of the Gaussian model (in hospital B) and Fourier series (in hospitals A and C). Besides, there was a positive correlation between the bare and fungal and bacterial concentrations. Finally, the most effective bare radius of application on the indoor and outdoor fungi was 4 and 5 km, respectively (R2 = 0.99). The effective radius for reducing fungi and bacteria by creating green space was 0.5 and 3 km from the hospital center (R2fungi = - 0.99, R2bacteria = - 0.8). Based on these results, land use is an effective factor in airborne fungi and bacteria in hospitals. Therefore, their control and management of land use during 5 km is necessary to reduce pollution.
Keywords: Bacteria; Effective radius; Fungi; Indoor and outdoor air; Land use.