239(240),238Pu, 90Sr, 103Ru and 137Cs concentrations in surface air in Austria due to dispersion of Chernobyl releases over Europe

After the reactor accident at Chernobyl on 26 April 1986, Austria was one of the most stricken countries. Radionuclide concentrations in surface air were measured at five different sampling stations, viz. in Vienna, Linz, Salzburg, Bregenz and Klagenfurt, during the period 28 April - 9 May 1986. In addition to the results of the γ-spectroscopic measurements of 103Ru and 137Cs, data for 239(240),238Pu and 90Sr determined by radiochemical analyses of the same air filters are presented. These results show that in Austria generally most of the 137Cs and 103Ru contamination occurred before 2 May, whilst most of the 90Sr and 239(240)Pu contamination took place between 2-5 May. Initially 103Ru/137Cs ratios of ∼ 2 could be observed, which later decreased to 0.3-0.6 and increased again after 2 May, up to as high as 5. The ratios of 90Sr/137Cs remained between 0.004 and 0.017, those of 239(240)Pu/137Cs between 1.3 x 10-6 and 2 x 10-5. (author)