Allocation of excessive cancer risk induced by benzene inhalation in 11 cities of Europe in atmospheric circulation regimes

Daily atmospheric concentrations of benzene, measured during the years 2008-2012 in 11 European cities, were analyzed in terms of atmospheric circulation. Benzene levels in central continental Europe and Northern Europe were clearly enhanced by extended anticyclones located over North West Russia (NWR), whereas weak gradient conditions, which are associated with light winds, were connected with the degradation of air quality across Southern Europe due to recirculation of polluted air. The calculated Incremental Lifetime Cancer Risk (ILCR) indicated potential health risks for humans due to the inhalation of benzene at all areas, whilst not recommendable ILCR values were detected at all traffic sites. The estimated ILCR was also allocated in the produced atmospheric circulation regimes, based on an approach which took into account the average benzene concentration corresponding to each synoptic pattern along with its frequency of occurrence. Synoptic regimes associated with increased benzene levels commonly accounted for large fractions of the total risk however in some cases the impact of highly polluted atmospheric regimes on ILCR was reduced, due to the lack of appearance of these atmospheric circulation types.