Major ionic species in size-segregated aerosols and associated gaseous pollutants at a coastal site on the Belgian North Sea
Horemans, B.; Krata, A.; Buczynska, A.J.; Dirtu, A.C.; Van Meel, K.; Van Grieken, R.; Bencs, L. (2009). Major ionic species in size-segregated aerosols and associated gaseous pollutants at a coastal site on the Belgian North Sea. J. Environ. Monit. 11(3): 670-677. dx.doi.org/10.1039/b815059a In: Journal of Environmental Monitoring. The Royal Society of Chemistry: Cambridge. ISSN 1464-0325; e-ISSN 1464-0333, more | |
Abstract | The chemical composition of airborne particulate matter (PM) was studied at a coastal region near De Haan, Belgium, during a winter–spring and a summer campaign in 2006. The major ionic components of size-segregated PM, i.e. NH4+, Na+, K+, Mg2+, Ca2+, Cl-, NO3-, and SO42-, and related gaseous pollutants (SO2, NO2, NH3, HNO2, and HNO3) were monitored on a daily basis. Air mass backwardtrajectories aided in evaluating the origin of the diurnal pollution load. This was characterised with high levels of fine secondary inorganic aerosols (NH4 +, NO3-, and non-sea-salt SO42-) for continental air masses, and sea-salts as the dominant species in coarse maritime aerosols. Seasonal variations in the level of major ionic species were explained by weather conditions and the release of dimethyl sulfide from marine regions. This species was responsible for an increased sea-salt Cl- depletion during summer (56%), causing elevated levels of HCl. Neutralisation ratios for the coarse fraction (0.6–0.8) suggested a depleted NH4+ level, while that for the fine fraction (1.1–1.3) had definitely an excess of NH4+, formed by the neutralisation of HCl. The results of factor analysis and the extent of SO2 oxidation indicated that the major ionic species originated from both local and remote sources, classifying the Belgian coastal region as a combined source–receptor area of air pollution. |
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