The contributions of an airport and related road network to Pseudevernia furfuracea bioaccumulation of trace elements and polycyclic aromatic hydrocarbons

The use of a high-density lichen transplant network together with quantitative wind relationships (WQRs) made it possible to evaluate the influence of an airport and surrounding road network on the spatial variation of polycyclic aromatic hydrocarbons (PAHs) and trace elements at both the local and whole study area scale. WQRs clearly showed that the parking/idling/taxiing area (PIT), but not the landing/take-off zones (LTZs), as well as the north/north-east part of the road network were contributors at the whole study area scale to the spatial variation of elements like Ni, Mo and V, i.e. those associated with ultrafine particles due to their involvement in anti-wear materials, and of total PAHs. In the case of an airport, such a result can have strong management implications. Traffic also affected the concentration of the prevailing volatile organic compounds. In contrast, LTZs and high traffic density values were correlated with peaks of Zn, Mo, Cu, Co, Mn, Ni, V, Al and Sb when associated with coarse particulate matter generated by deterioration of the landing gear, fuselage, wings, runway asphalt and brakes. The remarkable percentage of high-speed winds strongly affected both the spatial distribution of anthropogenic emissions and their atmospheric dilution, resulting in a rather low level of contamination. Our results suggest that biomonitoring can be much improved when matched with WQRs and that, in the event of high wind speeds, PAHs associated with the gas phase and fine/ultrafine particles are effective contamination tracers mainly at the whole study area scale whereas trace elements reveal contamination patterns at both scales.