Chemical Composition  and Source Origin of Fine Aerosol Particles in Budapest, Hungary


A contribution to subproject SATURN

László Bozo, Joseph M. Pinto and Krisztina Labancz

Hungarian Meteorological Service, Institute for Atmospheric Physics
1675 Budapest P.O.Box 39., Hungary
bozo@met.hu




1. Summary

Fine aerosol samples were collected at 2 receptor sites in Budapest and analysed for Cd, Cu, Ni,  Pb, V and Zn by XRF method. Major fine aerosol sources were also evaluated based on the sampling in pollutant plume. Source and receptor profiles are connected with a Chemical Mass Balance (CMB) type source-receptor model so that to estimate the relative contribution of potential pollution sources to the ambient fine aerosol profile.

2. Aim of the research

Some of the trace gases like SO2, NO, NO2, O3 and total (PM10) aerosol mass have been monitored for a long period in Budapest. Much less is known about the mass and chemical composition of  fine (PM2.5) aerosol particles, although they have harmful effects on human health. The aim of the research is not simply to monitor the fine aerosol concentration and chemical composition but also to pin-point their source categories and find the best-fitting linear combination of source profiles to reproduce the measured receptor profile. The results of research are expected to help the decision makers to elaborate a cost effective emission abatement strategy for Budapest.
 

3. Activities during the year

Source profiles of Cd, Cu, Ni, Pb, V and Zn for waste incineration, traffic, oil and coal burning were applied for model calculations. Aerosol sampling for fine size range aerosol particles was carried out by Harvard type impactors at the sources and the receptor point, downtown Budapest. Source signatures for coal and oil burning were adopted from the fine size range aerosol measurements carried out in the plume of power plants operating in the Czech Republic.
 

4. Principal results

The concentration of different species in the atmospheric aerosol is influenced significantly by human activities, so the study of the source origin of elements in aerosol particles is of crucial importance for environmental management on urban scale. Elemental composition of atmospheric aerosol particles over Budapest and regional background conditions in Hungary was investigated in details by Molnár et. al (1993). The main goal of that paper was to evaluate the characteristics of 18 elements of natural and anthropogenic origin under different conditions in Hungary. Receptor modeling applied in present paper provides quantitative estimates of the impacts of sources on ambient air. In contrast to dispersion modeling it applies only minimal meteorological and emission inventory information. The Chemical Mass Balance method has been developed to estimate the source contributions to ambient concentration levels. Its general aim is to reach minimum cost emission control strategies that will be effective in reducing the ambient concentrations of pollutants considered. The concentration Ci of species i measured at receptor site is expressed as:
 
 



where Aij is the abundance of species i in the profile of source j, and Sj is the mass concentration at the receptor site due to source j. This series of equations is simultaneously solved for each Sj by minimizing the reduced chi square:
 






where ei is a residual, Ns is the number of fitting species, Nc is the number of sources, and Ei2 is an effective variance which includes uncertainties in both Aij and ci. Source profiles for waste incineration and traffic are shown in Figures. 1. and 2.
 
 





It was found that high amount of Zn, Pb and Cu is emitted from a waste incinerator in Budapest, while regarding the traffic profile, the most important element is Pb.
 
 





Average receptor profile, integrating all the contributions from different source categories is plotted in Figure. 3. Measurements campaign is being continued at 3 receptor points in Budapest as well as in the plumes of relevant point and line sources so that to extend the investigations towards the relationships between meteorological conditions and receptor profiles.
 
 


5. Main conclusion

It was concluded (Figure. 4.) that waste incineration provides the most significant contribution (71%) to the toxic metal load in Budapest. The relative contribution of traffic sources is 8%. Coal burning has no significant importance in Budapest regarding the contribution to the receptor profile. It can be explained by the fact that coal consumption was significantly reduced in Budapest during the past decades since it was replaced by natural gas at most of the industrial, energetical and residential sources.


6. Aim for the coming year

Number of sampling points are to be increased during the coming year. Receptor profiles will be evaluated as a function of relevant meteorological conditions. Source profiles for coal and oil burning will also be inventorized in more details.

7. Acknowledgements

This paper was sponsored by the U.S.-Hungarian Science and Technology Joint Fund in cooperation with U.S. Environmental Protection Agency and Hungarian Meteorological Service under Project J.F.No. 565.

8. Reference

Molnár A., Mészáros E., Bozó L., Borbély-Kiss I., Koltay E. and Szabó Gy.; Elemental composition of  atmospheric aerosol particles under different conditions in Hungary. Atmospheric Environment 27A, 1993, pp. 2457-2461.