Word: fissioning
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...this flow of information is based the official AEC position, recently expressed by Scientist-Commissioner Willard F. Libby. In general. Chemist Libby's view is calm. As a scientist, he knows that fission products from megaton* explosions rise into the stratosphere and circulate round the earth for years. Most threatening of them is strontium 90, whose long half-life (28 years) keeps it potent during its stratospheric circling, and whose habit of lodging for keeps in human bone makes it a probable cause of leukemia and bone cancer...
...about 3% of the natural radiation exposure." Another Libby example: a person moving into a concrete-block house in certain countries may get up to 100 times as much additional radiation from naturally radioactive elements in the concrete as he is getting from present fallout. He recognizes that fission products from past tests are still stored in the stratosphere and that they will soon be joined by the products of new tests. This is not worrisome either, he says: "If tests were to continue until 1983 at the rate of the past five years, [fallout radiation] levels...
...large-scale testing. Italian scientists, from Roman Catholics to Communists, agree that too little is known to justify taking risks with the world's health. Most German scientists feel the same way. The Japanese, who get fallout from both east and west, are especially emphatic. They believe that fission products now in the stratosphere may be dangerous already and will surely become so unless the testing is stopped. Says Physicist Mitsuo Taketani of Rikkyo University: "The U.S. and the U.S.S.R. are not testing now. They are conducting nuclear bomb and weapons maneuvers. The whole population of the world...
Better Chemists. Weiss and Shipman dried the clam flesh, reduced it to ash and dissolved the ash in dilute acid. The solution showed characteristic gamma rays that could come only from cobalt 60. This was odd, they thought; cobalt 60 is not a fission product, and it had not been found in other radioactive material, even in samples from much closer to Ground Zero. To make doubly sure. Weiss and Shipman ran a careful analysis. One clam proved to contain one-tenth of a microcurie of cobalt 60; the other had one-third of a microcurie...
Since the dangerously radioactive cobalt 60 is not a product of fission, it must have come from some other element, perhaps nonradioactive cobalt 59, exposed to free neutrons given off by the thermonuclear explosion. It could never have been more than a trace in the sea water, or the careful tests made in the Marshalls just after the explosion would have detected it. But clams are apparently better chemists than men are; they went after the cobalt 60 for reasons of their own and collected an astonishing amount of the radioacitve isotope...