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Particulate matter measurements (PM10, PM2.5) using a beta radiation attenuation monitor were performed at the Akrotiri research station (May 2003-March 2006) on the island of Crete (Greece). The mean PM10 concentration during the measuring period (05/02/03-03/09/04) was equal to 35.0 +/- 17.7 mu g/m(3) whereas the mean PM2.5 concentration (03/10/04-04/02/06) was equal to 25.4 +/- 16.5 mu g/m(3). The aerosol concentration at the Akrotiri station shows a large variability during the year. Mean concentrations of particulate matter undergo a seasonal change characterised by higher concentrations during summer [PM10, 38.7 +/- 10.8 mu g/m(3) (2003); PM2.5, 27.9 +/- 8.7 mu g/m(3) (2004) and 27.8 +/- 9.7 mu g/m(3) (2005)] and lower concentrations during winter [PM10, 28.7 +/- 22.5 mu g/m(3) (2003/2004); PM2.5, 21.0 +/- 13.0 mu g/m(3) (2004/2005) and 21.4 +/- 21.9 mu g/m(3) (2005/2006)]. Comparative measurements of the PM10 concentration between the beta radiation attenuation monitor, a standardized low volume gravimetric reference sampler and a low volume sequential particulate sampler showed that PM10 concentrations measured by the beta radiation attenuation monitor were higher than values given by the gravimetric samplers (mean ratio 1.17 +/- 0.11 and 1.21 +/- 0.08, respectively). Statistical and back trajectory analysis showed that elevated PM concentrations (PM10, 93.8 +/- 49.1 mu g/m(3); PM2.5: 102.9 +/- 59.9 mu g/m(3)) are associated to desert dust events. In addition regional transport contributes significantly to the aerosol concentration levels whereas low aerosol concentrations were observed during storm episodes.