Spatial distribution of PAH concentrations and stable isotope signatures (d13C, d15N) in mosses from three European areas e Characterization by multivariate analysis

Polycyclic aromatic hydrocarbon (PAH) concentrations and N, C stable isotope signatures were determined in mosses Hypnum cupressiforme Hedw. from 61 sites of 3 European regions: Île-de-France (France); Navarra (Spain); the Swiss Plateau and Basel area (Switzerland). Total PAH concentrations of 100e700 ng g!1, as well as d13C values of !32 to !29& and d15N values of !11 to !3& were measured. Pearson correlation tests revealed opposite trends between high molecular weight PAH (4e6 aromatic rings) content and d13C values. Partial Least Square regressions explained the very significant correlations (r > 0.91, p < 0.001) between high molecular weight PAH concentrations by local urban land use (<10 km) and environmental factors such as elevation and pluviometry. Finally, specific correlations between heavy metal and PAH concentrations were attributed to industrial emissions in Switzerland and road traffic emissions in Spain.