Evaluation of NO2 and NH3 concentration levels in Kaunas using two different passive sampling methods

The aim of the present study was to evaluate NO2 and NH3 levels in Kaunas and to compare results of nitrogen dioxide concentration measured by two different passive sampling methods. Two different passive sampling methods were used for nitrogen dioxide concentration determination. The first method was developed by M. Ferm (1991), the second one – by D. Krochmal and A. Kalina (1997). NH3 concentration was determined by the same M. Ferm (1991) method. Sampling was carried out in Kaunas city in June of 2010. According to measured concentration comparison of two methods was done. The study results showed that mean nitrogen dioxide concentration in Kaunas city measured by passive method developed by M. Ferm (1991) was 18.7 µg m-3, and 22.6 µg m-3 developed by D. Krochmal and A. Kalina (1997). The highest nitrogen dioxide concentration was determined in city centre, Birštono street, and was quite similar measured by both methods (31.3 µg m-3 by M. Ferm method and 32.2 µg m-3 by D. Krochmal and A. Kalina method). Lowest nitrogen dioxide concentration was determined in recreational zone, J. Basanavičiaus stand, in Vičiūnai district (9.3 µg m-3 measured by M. Ferm method and 11.7 µg m-3 measured by D. Krochmal and A. Kalina method). The range of NH3 concentration was 16.5-32.9 µg m-3 with the mean concentration 22.1 µg m-3. The highest concentration of NH3 was observed in the park near ZooAplinkotyros katedraVytauto Didžiojo universiteta