In Europe, PAHs are regulated and their ambient air monitoring has been mandatory since 2004 (European Directive 2004/107/CE). As to date, no national cartography has ever been reported for any country and the study of long temporal trends of PAHs is poorly documented in literature. The long term evolution of the contribution of B[a]P to the ambient air PAH mixture has not yet been properly documented in literature even if this compound has been chosen as the marker for the suite of PAH compounds. Based on the data from the statutory monitoring performed by the local air quality network, the objective of this work was to complete a French cartography of atmospheric PAHs and to study their spatial and temporal variations in concentrations and profiles (B[a]P/?7PAHs and B[a]P/PM10). Temporal trends were investigated on selected monitoring sites (monitoring periods > 5 years) factoring in the emission time trends, location and seasonal effect. Results obtained showed that, at a national scale, B[a]P annual mean concentration levels are lower than the European Directive target value of 1 ng m-3. Only industrial sites and some urban sites located in specific regions, characterized by their considerable industrial activity, their relief and/or their geographical location, showed higher annual mean concentrations. The highest contributions of B[a]P/PM10 ratios were observed on industrial sites, and its large seasonal variations observed on urban, suburban and rural locations highlighted the major contribution of residential heating to the toxicity of the PM in winter period. A statistical time-series model was applied to decompose and analyze long term trends. Results obtained showed a significant decrease in PAH concentration levels (- 1 ng m-3 in 10 years) for all the selected sites. Only half of them showed a significant decrease of the contribution of B[a]P on PM. Finally, results showed that the choice of B[a]P as representative of PAH chronicle contamination is questionable. Differences in temporal evolution of the contribution of B[a]P to the mixture of PAH was clearly observed between monitoring sites from different regions. This work was supported by the French Ministry of Ecology, Sustainable Development and Energy (MEDDE) and by the French central laboratory of air quality monitoring (LCSQA)