Total B - activity in monitor small rodents species from two different altitudes in Rila Mountain (Bulgaria)

Radioecological studies on monitor small rodents species from two different altitudes in Rila Mountain (South-West Bulgaria) were investigated. Yellow-necked mouse (Apodemus flavicollis) and bank vole (Myodes (Clethrionomys) glareolus) from the area of Beli Iskar (1500 m s. l.) and yellow-necked wood mouse (Apodemus flavicollis) and snow vole (Chionomys nivalis) from the peak Moussala (2925 m s. l.) were used to assess the environmental state. The radiometric measurements were carried out using a low-background beta counter (LAS 3A level activity system with 30 % efficiency on 40K). Comparisons of the data obtained from total β-activity measurements show some differences in the bioaccumulation among monitor species from the two regions. The values in the investigated rodents show high variation: from 144 up to 1081 Bq.kg−1 without region and species dependence. In Ap. flavicollis from Moussala they vary from 144 up to 309 Bq.kg−1 and from 168 up to 491 Bq.kg−1 for the lower altitude. For M. glareolus these values reach 1081 Bq.kg−1. Measurements from the bodies of the Ch. nivalis from the peak Moussala varied from 203 to 623 Bq.kg−1. The obtained results can be considered as normal. The data show values up to ten times lower in comparison with the same measurements twenty years ago.Radioecological studies on monitor small rodents species from two different altitudes in Rila Mountain (South-West Bulgaria) were investigated. Yellow-necked mouse (Apodemus flavicollis) and bank vole (Myodes (Clethrionomys) glareolus) from the area of Beli Iskar (1500 m s. l.) and yellow-necked wood mouse (Apodemus flavicollis) and snow vole (Chionomys nivalis) from the peak Moussala (2925 m s. l.) were used to assess the environmental state. The radiometric measurements were carried out using a low-background beta counter (LAS 3A level activity system with 30 % efficiency on 40K). Comparisons of the data obtained from total β-activity measurements show some differences in the bioaccumulation among monitor species from the two regions. The values in the investigated rodents show high variation: from 144 up to 1081 Bq.kg−1 without region and species dependence. In Ap. flavicollis from Moussala they vary from 144 up to 309 Bq.kg−1 and from 168 up to 491 Bq.kg−1 for the lower altitude. For M. glareolus thes...