Influence of Air Pollutants in the 7Be Size Distribution of Atmospheric Aerosols

The atmospheric behavior of 7Be aerosols was studied by using 1-ACFM cascade impactors. The activity distribution of Be measured by gamma spectrometry (Eγ=477 keV), was largely associated with submicron aerosols in the accumulation mode (0.4-2.0 μm). The activity median aerodynamic diameter, AM AD ranged from 0.62 to 1.00 yam (average 0.80 μm). The geometric standard deviation, σg ranged from 1.87 to 2.50 (average 2.22). Low AMADs of 7Be aerosols have been observed at locations characterized with relatively low pollution. Some dependency of AMADs on height has been also observed. In near marine environment the 7Be activity size distribution was observed in higher size range of aerosol particles (AMAD 0.82 μm).