BACKGROUND CONCENTRATIONS OF RA-226 IN TERRESTRIAL ANIMALS

Radium (Ra-226) accumulation by terrestrial animals was studied in the territory of the former USSR. Concentrations of Ra-226 in different s oils, plants and animals are similar to the background level. For soil s it fluctuates in range 0.5-1.5 x 10(-12) g g(-1) (18.3-55 Bq/kg), fo r plants between 0.1-1.7 x 10(-12) g g(-1) (3.7-62.1 Bq/kg), and for a nimals - 0.02-1.5 x 10(-12) g g(-1) (0.73-55 Bq/kg). There were no sig nificant differences in Ra-226 concentration between animals of differ ent groups. The maximal Ra-226 concentration is marked for the woodlou se Hemilepistus aphganicus from the Badkhyz reserve in Turkmenistan - 1.49 x 10(-12) g g(-1) of dwt (54.4 Bq/kg), the minimal one - for Colo rado beetle Leptinotarsa decemlineata from the vicinity of Moscow - 0. 02 x 10(-12) g g(-1) of dwt (0.73 Bq/kg). Concentration ratios for lin ks soil - plant, plant - animal and prey - carnivore are usually close to 1. A hypothesis on the similarity of Ra-226 concentration in diffe rent animals is discussed.