This experimental work deals with the kinetic study of the reactions of nitrogen dioxide (NO 2 ) radical with tri- to hexa-aromatic hydrocarbons adsorbed on silica particles. Measurements were performed using a flow-tube, at 295K, in the absence of light. Polycyclic aromatic hydrocarbons (PAHs) were extracted from particles by focused microwave extraction and analyses were performed using gas chromatography coupled to mass spectrometry (GC/MS). Rate constants varied from 1.4×10 −3 to 4×10 −8 s −1 , depending on the structure of the PAH, for NO 2 concentration of 1.5×10 12 moleculescm −3 . Benzo[a]pyrene was the most reactive, with a lifetime regarding NO 2 of a few minutes in polluted air conditions. The comparison of these results with those previously reported for carbonaceous particles leads to the conclusion that gas/solid interface reactivity of PAHs depends on the nature of the particle.