In this paper, we present the very first determinations of atmospheric concentration of SO2, HCl and HF in rural locations of the Etnean area. Data were gathered with a network of 18 passive samplers, distributed on the slopes of the volcano at distances between 0.8 and 11.2 km from the summit craters and exposed for a period of one month (June 2002). Data analysis reveals that acid gas concentrations in air, ranging 3 -720 μg/m3 (SO2), <0.5-74 μg/m3 (HCl) and <0.1-3.0 μ.g/m3 (HF), show an inverse relationship with distance from the summit craters, reflecting the progressive dilution of volcanogenic volatiles by air components. We also point out that gas concentration in the air are the highest on the eastern flank, which is generally downwind crater emissions due to prevailing westerly wind circulation. Concentrations measured in an urban site (Catania) about 26 km away from the summit crater are significantly higher (SO2 = 21 μg/m3; HCl = 2.8 μg/m3) than background values in the area.