Isotopic composition and source of plutonium in the Qinghai-Tibet Plateau frozen soils.

ABSTRACT: The ^239+240Pu activities and ²⁴⁰Pu/²³⁹Pu atom ratios in the frozen soils of the Yellow River Source Area (YRSA) were determined to examine the Pu source and evaluate its environmental risk. The ^239+240Pu activities of surface frozen soils in the YRSA, ranging from 0.053 to 0.836 mBq g^-1, are comparable to those observed in China elsewhere (0.005-1.990 mBq g^-1). The ²⁴⁰Pu/²³⁹Pu atom ratios of surface soils in the YRSA are in the range of 0.168-0.201 (average = 0.187 ± 0.012, n = 6), comparable to the global fallout of 0.180 ± 0.014. Based on the latitudinal and spatial distribution of Pu isotopic composition, I clarified that the Pu source is mainly from global fallout at present. The activity levels of

SUBMITTER: Wu J 

PROVIDER: S-EPMC6536505 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature