  Real-time monitoring of individual particles from atmospheric aerosols was
performed by means of a specifically developed single-particle fluorescence
spectrometer (SPFS). The observed fluorescence was assigned to particles
bearing polycyclic aromatic hydrocarbons (PAH). This assignment was supported
by an intercomparison with classical speciation on filters followed by gas
chromatography-mass spectrometry (GC-MS) analysis. As compared with
daily-averaged data, our time resolved approach provided information about the
physicochemical dynamics of the particles. In particular, distinctions were
made between background emissions related to heating, and traffic peaks during
rush hours. Also, the evolution of the peak fluorescence wavelength provided an
indication of the aging of the particles during the day.
