-l4 Measurements of Radioactivity Outside the U.5s. Samples of airborne dust will be taken at approximately 70 various localities throughout the world, tion to the U.S. stations. in addi- Previous studies of this kind have shown that the average gamma ray dosage delivered to world inhabitants by all tests to date is less than the dose the same period of time. ry 6 cf they have received from natural backgrcund radiation during Ail of these dosages are believed by radiclogists and radiobiologists to be narmless. Radiostrontium-90 nas been demonstrated to be potentially the most hazardous of bomb products which compose airborne dust or fallout. As in the past, soils will be sampled on a world-wide basis, and semples of other materials such as milk and cheese, field crops, and human and animal bones, will be taken for analysis of their radiostrontium content. These samplings are carried out, together with radiochemical analysis, for a 2-fold purpose: 1) to ascertain the world-wide distribution of radioactive fission products - particularly strontium-90 - in the air, water and soils of the earth as a result of atomic tests to date; 2) to ascertain the relationship of man to his environment, particularly as regards strontium-90. These observations, when combined with studies on the biological (more)