The influence of specific atmospheric circulation types on PM10-bound benzo(a)pyrene inhalation related lung cancer risk in Barcelona, Spain

Benzo(a) pyrene (BaP) is a Polycyclic Aromatic Hydrocarbon (PAH) well known for its carcinogenic effects. In this study, BaP levels in daily PM10 samples collected at 8 stations in Barcelona (Spain), during the years 2013-2015, were analyzed in relation to distinct atmospheric circulation patterns. Our objective was to estimate the BaP inhalation related Lung Cancer Risk (LCR) in connection with the prevailing synoptic conditions. Air masses were also analyzed in order to examine the possibility of transboundary BaP contributions. The influence of high pressure anticyclonic systems caused a sharp increase of PM10-bound BaP concentrations in all stations due to recirculation and accumulation of polluted air, whilst the calculated BaP inhalation related LCR values implied a potential health risk from BaP exposure and were not recommendable primarily at central heavily trafficked sites. However the LCR remained below the upper limit posed by United States Environmental Protection Agency (US EPA), even under the most stagnant atmospheric conditions. The elaboration of backward air mass trajectories with Concentration Weighted Trajectory (CWT) algorithm indicated that combustion emissions in Spain, France and the industrialized Northern coast of Algeria are potential contributors to the PM10-bound BaP concentrations measured in Barcelona.