Scavenged 239Pu, 240Pu, and 241Am from snowfalls in the atmosphere settling on Mt. Zugspitze in 2014, 2015 and 2016.

ABSTRACT: Concentrations of 239Pu, 240Pu, and 241Am, and atomic ratio of 240Pu/239Pu in freshly fallen snow on Mt. Zugspitze collected in 2014, 2015 and 2016 were determined by accelerator mass spectrometry (AMS). For the sub-femtogram (10-15 g) - level of Pu and Am analysis, a chemical separation procedure combined with AMS was improved and an excellent overall efficiency of about 10-4 was achieved. The concentration of 239Pu ranges from 75?±?13 ag/kg to 2823?±?84 ag/kg, of 240Pu from 20.6?±?5.2 to 601?±?21 ag/kg, and of 241Am was found in the range of 16.7?±?5.0-218.8?±?8.9 ag/kg. Atomic ratios of 240Pu/239Pu for most samples are comparable to the fallout in middle Europe. One exceptional sample shows a higher Pu concentration. High airborne dust concentration, wind directions, high Cs concentrations and the activity ratio of 239+240Pu/137Cs lead to the conclusion that the sample was influenced by Pu in Saharan dust transported to Mt. Zugspitze.

SUBMITTER: Guckel K 

PROVIDER: S-EPMC5605513 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature