Retrospective determination of fallout radionuclides and 236U/238U, 233U/236U and 240Pu/239Pu atom ratios on air filters from Vienna and Salzburg, Austria. (December 2022)

• Record Type: Journal Article
• Authors: Wallner, G.; Uguz, H.; Kern, M.; Jirsa, F.; Hain, K.
• Is Part Of: Journal of environmental radioactivity. Volume 255(2023)
• Publication Date: 2022-12
• Subjects: 240Pu/239Pu -- 236U/238U -- 233U/236U -- Air filters -- Bomb peak -- AMS; Radioactivity -- Periodicals; Radiation, Background -- Periodicals; Radioecology -- Periodicals; Radioactive pollution -- Periodicals; Environmental Pollutants -- Periodicals; Radioactive Pollutants -- Periodicals; Radioactivity -- Periodicals; Radioécologie -- Périodiques; Pollution radioactive -- Périodiques; Fond de rayonnement -- Périodiques; 539.752
• DOI: 10.1016/j.jenvrad.2022.107030
• Languages: English
• ISSNs: 0265-931X

Abstract

Abstract: 137 Cs and 241 Pu (via 241 Am) concentrations were measured γ-spectrometrically on air filters from the early 1960s (mainly from 1964–66) from Vienna, Austria, and an alpine station in Salzburg, Austria. Accelerator mass spectrometry (AMS) was used to determine 240 Pu/ 239 Pu, 236 U/ 238 U and 233 U/ 236 U atom ratios as well as 236 U, 239 Pu and 240 Pu atom concentrations. The maximum 236 U/ 238 U atom ratio of these unique undisturbed global fallout samples was (1.19 ± 0.31) × 10 −5 in spring 1964. The 233 U/ 236 U atom ratios were found within (0.15–0.49) × 10 −2 and indicate that the weapons tests of the early 1960s can be excluded as 233 U source. The 236 U/ 239 Pu atom ratios were calculated in the range of 0.22–0.48. Highlights: 3 months average values of 240 Pu/ 239 Pu, 236 U/ 238 U and 233 U/ 236 U atom ratios of aerosols from the early 1960s. 233 U/ 236 U atom ratios support the hypothesis of maximum 233 U release already in the 1950s. The nuclear weapons tests of the early 1960s can be exclude as a possible 233 U source.