Institut de Radioprotection et de Sûreté Nucléaire (IRSN), LEREN, Cadarache, 13115, Saint Paul lez Durance, France.
Institut de Radioprotection et de Sûreté Nucléaire (IRSN), LEREN, Cadarache, 13115, Saint Paul lez Durance, France.
J Environ Radioact. 2019 Nov;208-209:106029. doi: 10.1016/j.jenvrad.2019.106029. Epub 2019 Sep 3.
Long term radioactivity monitoring programs contribute to the understanding of the behavior of radionuclides in the environment. This work aims to investigate the long term behavior of Cesium-137 in pasture ecosystem (root soil, grass and cow's milk) by using of more than twenty five years monitoring data collected at ten of French pasture sites contaminated by atmospheric fallouts from Chernobyl and nuclear atmospheric tests. We estimated with a simple exponential model the long term effective half-lives of radiocesium in root soil, grass vegetation and cow's milk along with their associated uncertainties. The average values of the effective half-lives over all the investigated sites were determined as 17, 11 and 9 years for soil, grass and milk respectively. Those values compare favorably to those estimated in previous studies in literature. These findings further enable us to quantify the decrease of Cs bioavailability which ranges from 0.008 to 0.044 year with an average value of 0.026 year (i.e. effective half lives ranging from 16 to 87 years with an average value of 26 years in soil).
长期放射性监测计划有助于了解放射性核素在环境中的行为。本工作旨在通过对来自切尔诺贝利和核大气试验的大气沉降物污染的十个法国牧场的二十五年以上监测数据的研究，调查铯-137在牧场生态系统（根土、草和牛奶）中的长期行为。我们使用简单的指数模型估计了根土、草植被和牛奶中放射性铯的长期有效半衰期及其相关不确定性。在所有调查地点的有效半衰期平均值分别为 17、11 和 9 年，分别为土壤、草和牛奶。这些值与文献中先前研究中估计的值相当。这些发现使我们能够进一步量化 Cs 生物利用度的降低，范围从 0.008 到 0.044 年，平均值为 0.026 年（即有效半衰期从 16 到 87 年，平均值为 26 年在土壤中）。
