To better understand the source and fate in the atmosphere of PAH derivatives, two complementary approaches were used: laboratory reactivity experiments in controlled conditions and field studies. Reactivity studies were carried out by exposing natural ambient air particles to oxidants (O3, OH and NO2/O3). Large decays of PAHs were observed and B[a]P appeared as the most reactive. The formation of oxygenated PAHs (OPAHs) and nitrated PAHs (NPAHs) was showed. However, quantities formed were not sufficient to explain the total amount of PAHs that reacted, highlighting the formation of other compounds not detected in this work. Field campaigns were performed on two different sampling sites around Paris. Concentrations were 10 times higher at the traffic site than at the suburban one. OPAHs and PAHs major compounds were similar at both sites, in contrary to NPAHs. The traffic site was influenced by primary emissions, whereas high amounts of secondary species were quantified at the suburban site. Particle size distribution of OPAHs and NPAHs showed their strong association to the finest particles (Dp < 2.5 μm), highlighting the interest of their study considering sanitary impacts.Les hydrocarbures aromatiques polycycliques (HAP) sont des composés réglementés dans l’air ambiant en raison de leurs propriétés cancérigènes et mutagènes avérées. Ces composés, émis par tous les processus de combustion, peuvent réagir avec les oxydants atmosphériques (O3, NO2, OH, NO3, N2O5, etc.) et former des dérivés oxygénés (OHAP) et nitrés (NHAP) qui semblent plus toxiques que les HAP parents. Le travail présenté ici est centré sur l’étude des sources et le devenir dans l’atmosphère des HAP et de leurs dérivés par l’intermédiaire de deux approches complémentaires : expérimentations en laboratoire en conditions contrôlées et études de terrain
