Interest in environmental aerosol chemistry has grown over the last decade as a result of its role in both climate change and troposheric pollution. in this work, the combination of ToF-SIMS and SEM/EDX was employed to explore the surface chemistry of aerosols. The capabilities and limitations of ToF-SIMS were investigated using particles of known composition and size produced by a vibrating orifice aerosol generator (VOAG). Principal component analysis (PCA) proved to help in the distinction of particles of different types by consolidating the information generated by ToF-SIMS. (c) 2007 Elsevier B.V. All rights reserved.