OBJECTIVE Smog, which contains fine dusts, non-metal oxides, metals and organic compounds can have irritating, allergenic and immunomodulatory effects leading to the development of respiratory diseases and their exacerbations. The aim of the study was to search for a relationship between concentrations of air pollutants and the frequency of hospitalizations due to exacerbation of asthma, chronic obstructive pulmonary disease, or abnormalitis in breathing. METHODS Hospital admission data was accessed from the hospital digital in-formation system. From the publicly available database of the Chief Inspectorate for Environmental Protection, data concerning the concentrations of pollutants, such as PM2.5 and PM10, sulphur oxide IV (SO2), nitric oxide IV (NO2), carbon monoxide II (CO), benzene and ozone (O3), measured daily with hourly accuracy was used. The results of the average concentrations of air pollutants were compared with the rates of hospitalization in the corresponding time intervals. RESULTS A number of statistically significant correlations were shown indicating the role of increased concentrations of each of the tested contaminants in the frequency of hospitalizations. In particular, strongly positive correlations were shown between the frequency of hospitalizations due to COPD and PM2.5 and PM10, asthma with benzene and NO2, and for respiratory disorders in general with benzene, CO and SO2. CONCLUSIONS The results indicate that air pollution can be a significant modifiable risk factor for exacerbations of respiratory diseases and therefore its avoidance plays an important role in primary prevention.