The present work focuses on the characterisation of total suspended particulates (TSP) around the Teruel power station in NE Spain with special emphasis on sulphate aerosols due to their acidification potential. The specific objectives are the determination of the seasonal evolution of TSP levels and chemistry, and investigation of possible neutralisation processes for acidic aerosols in the atmosphere. Concentrations of the elements studied in TSP show a marked seasonal trend in the study period (July 1995 to July 1997) characterised by higher levels in spring-summer and relative low levels in autumn and winter. In the case of sulphate aerosols, this pattern may be attributed to higher SO2 oxidation in the summer and autumn, and to the higher frequency of impact of the emission plume on the surface in this period. A seasonal trend of SO2 oxidation rates is also found. The soil-related elements show a similar seasonal trend which is interpreted to be a consequence of the typical Mediterranean atmospheric dynamics (Sahara air mass intrusions, convective dynamics, and low precipitation scavenging during summer.) In addition to seasonal variations, a clear grain-size fractionation is observed for the different ions determined. SO42- and NH4+ are concentrated in the finest grain-size fraction, while NO3- Cl-, K+, Mg2+, Na+ are concentrated in relatively coarser fractions, and Ca2+ levels increase with the particle diameter. Neutralisation of sulphate acidic aerosols is carried out by NH4+ and minor amounts of Ca-2(+). The sulphate neutralising compounds are described by different analytical methods.