Transfer factors of 226Ra, 232Th and 40K from soil to pasture-grass in the northeastern of Turkey.

The uptake of natural radioactivity by pasture-grass collected from seven different grasslands of Digor was calculated. The activities of 226Ra, 232Th and 40K in pasture-grass were in the range of 21.8 ± 6.3-49.6 ± 13.4, 51.9 ± 13.2-127.7 ± 23.8 and 309.5 ± 33.5-807.3 ± 64.4 Bq kg−1, respectively. The soil to pasture-grass transfer factors were evaluated and determined to be in the range from 0.26 ± 0.13 to 0.69 ± 0.34, 0.64 ± 0.27 to 1.99 ± 0.40 and 0.64 ± 0.014 to 1.40 ± 0.032 for 226Ra, 232Th and 40K, respectively. The distribution of 226Ra and 232Th in different parts of pasture-grass indicated a decreasing tendency in order of root > stem > leaf. 40K mainly accumulated in stem of pasture-grass and is followed by declining trend stem > leaf > root. [ABSTRACT FROM AUTHOR]