Azaarenes in atmospheric particulate matter samples of three different urban sites in east of France

Azaarenes concentrations in East of France urban atmospheres through the period between April 2006 and February 2007 are described. Sampling sites were chosen to be representative of three different regions and were situated in Strasbourg (“Alsace region”), in Besançon (“Franche-Comté region”) and in Spicheren (“Lorraine region”). In order to compare the seasonal variability, the sampling campaigns have been performed during the four seasons in Strasbourg, and during two opposed seasons (summer and winter) in Besançon and in Spicheren. Moreover, the sampling campaigns have been performed during 6 h time intervals per day (04:00–10:00; 10:00–16:00; 16:00–22:00 and 22:00–04:00) to assess the diurnal variations of azaarenes concentrations. Mean total azaarenes concentrations were 2.8 ng m−3 in Strasbourg, 1.6 ng m−3 in Besançon and 1.0 ng m−3 in Spicheren. Seasonal variations in the azaarenes concentrations occur with the greatest abundance of all species in the colder months when combustion sources are greatest and when azaarene compounds are mainly associated with the particle phase. A diurnal variation of compound concentrations in the three sites, in warm period, has been observed in accordance with the intensity of the vehicle circulation, with highest concentrations during the morning (04:00–10:00) and the evening (16:00–22:00). In cold period, there is no difference of concentration between these two time intervals of high vehicle circulation in Strasbourg site and in Besançon site. Moreover, in Spicheren site, the highest concentrations were observed during the evening. In this way, it seems that the contribution of domestic heating influenced the diurnal variations of some compounds on the three sites.