DETERMINATION OF RA-226 IN FOOD SAMPLES BY A NEW METHOD USING POLYCARBONATE DETECTORS

A new method is introduced in this paper for determination of Ra-226 i n food stuffs when it is in equilibrium with its decay products in pre pared microprecipitates when alphas are detected by polycaronate detec tors when electrochemically etched. The microprecipitates were prepare d from food samples in particular from high level natural radiation ar eas of Ramsar, Iran by the collection of radium with lead as Pb/RaSO4. Then radium was coprecipitated by addition of small amounts of a bari um carrier leading to thin films or microprecipitates with negligible self absorption for alpha particles. The results compared to those obt ained by the emanation method are in good agreements.