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Salient. An Organ of Student Opinion at Victoria University College, Wellington N.Z. Vol. 20, No. 6. May 9, 1957

Rays and Cells

Rays and Cells

These rays have energies which on our scale of ray energies are far above those of heat and light rays and they have effects on matter which are far greater than those of the common rays. They consequently have effects on the cells of animals and plants and this makes them a considerable embarrassment to anyone using nuclear energy for war or peace.

The rays are produced in great numbers at the time of the original fission. But because in a bomb test this is soon over and in a reactor may be shielded by thick walls of concrete etc., this is not so serious. The unstable atoms (called radioactive isotopes) produced in fission take different times to shoot out their electrons and become stable. The time depends on the structure of the particular nucleus. Most of them go through most of the steps towards stability in seconds but when they are very nearly stable and only have one or so rays to shoot out the nucleus may wait years to do it. These are the fission products which are potentially the most dangerous.

The most dangerous ones of all are those whose chemistry is like that of some element common in animal bodies. A radioactive element with such a chemistry when absorbed in the body may substitute for the stable element which it is chemically similar to, and so is accumulated in the body rather than eliminated. The natural radioactive element radium has always been a particular menace because it is taken up by the bones in place of calcium. Now in fusion reactions we are producing a radio isotope strontium-90 which has a chemistry similar to calcium.

If a radioactive element accumulates in any part of the body the tissue around is bombarded by the rays given off as the isotope decays to a stable nucleus. The cells may be damaged and cease to function properly, if the bones contain much radioactive material the marrow is damaged by radiation and leukemia starts and the patient has little chance of living. Many famous physicists who due to the ignorance of the danger were careless with radium have died of leukemia. The picture has one saving feature, cancer cells in the body may be killed in preference to healthy ones by radiation and several other kinds of growth may be killed by rays. Sometimes it is simply stated that radiations produce cancer. This may have to be reviewed in the light of present work on this disease but we definitely know that radiation sometimes does produce cancer, but a fair amount of radiation is required.