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

G Wallner; H Uguz; M Kern; F Jirsa; K Hain

doi:10.1016/j.jenvrad.2022.107030

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

J Environ Radioact. 2022 Dec:255:107030. doi: 10.1016/j.jenvrad.2022.107030. Epub 2022 Sep 30.

Authors

G Wallner¹, H Uguz², M Kern³, F Jirsa⁴, K Hain³

Affiliations

¹ Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria. Electronic address: [email protected].
² Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria.
³ Faculty of Physics, Isotope Physics, University of Vienna, Währingerstr. 17, A-1090, Vienna, Austria.
⁴ Faculty of Chemistry, Institute of Inorganic Chemistry, University of Vienna, Währingerstr. 42, A-1090, Vienna, Austria; University of Johannesburg, Department of Zoology, Auckland Park, 2006, South Africa.

PMID: 36191507
DOI: 10.1016/j.jenvrad.2022.107030

Abstract

¹³⁷Cs and ²⁴¹Pu (via ²⁴¹Am) 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 ²⁴⁰Pu/²³⁹Pu, ²³⁶U/²³⁸U and ²³³U/²³⁶U atom ratios as well as ²³⁶U, ²³⁹Pu and ²⁴⁰Pu atom concentrations. The maximum ²³⁶U/²³⁸U atom ratio of these unique undisturbed global fallout samples was (1.19 ± 0.31) × 10^-5 in spring 1964. The ²³³U/²³⁶U 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 ²³³U source. The ²³⁶U/²³⁹Pu atom ratios were calculated in the range of 0.22-0.48.

Keywords: (233)U/(236)U; (236)U/(238)U; (240)Pu/(239)Pu; AMS; Air filters; Bomb peak.

MeSH terms

Air Filters*
Austria
Plutonium* / analysis
Radiation Monitoring* / methods
Radioactive Fallout* / analysis
Retrospective Studies
Uranium* / analysis

Substances

Plutonium
Radioactive Fallout
Uranium