H2S, PM2.5, O3, NO2, SO2 and meteorological parameters such as temperature, relative humidity, precipitation, wind
speed and wind direction were measured simultaneously in an eastern Croatian town called Slavonski Brod during the
season winter/spring 2010. Emissions from the nearby cross-border (Bosnia and Herzegovina) oil refinery were identified
as sources of temporary elevated concentrations of H2S. The maximum daily averages of PM2.5 concentrations during
the winter period were as high as 240 mg m–3 which is a value 10 times greater than the threshold prescribed by the
World Health Organization. It is considered that the heating season, dense traffic, intense industrial activities and temperature
inversion during stable weather conditions are prevailing contributors to higher winter concentrations of PM2.5.
The results of the principal component analysis technique (PCA) have shown that lower air temperature, lower wind
speed and higher relative humidity play a significant role in the winter pollution episodes. From a public health point of
view, implementation of measures aimed at reducing the levels of H2S and PM2.5 should be considered
