Determination of131I in milk using heterogeneous liquid scintillation counting

Possibilities of the method based on both the selective separation of radioiodine from milk using anion-exchange resin as well as the131I counting in heterogeneous mixture of this anex with a liquid scintillator are presented. For samples of 4 dm3 volumes, the separation and counting efficiencies about 78% and 45% are achieved. Under the same experimental conditions the background rate is about 0.25 CPS /15 CPM/ and the LLD corresponds to about 7 mBq.dm−3 /0.2 pCi. dm−3/.