from:
http://www.mindfully.org/Nucs/2003/Stro ... 8nov03.htm
Ernest Sternglass, Ph.D., Professor Emeritus of Radiological Physics at
the University of Pittsburgh Medical School has written numerous articles
on the health effects of low-level radiation. He is Director and Chief Technical
Office of the RPHP Baby Teeth Study [
www.rphp.org].
In 1963, Dr. Sternglass was invited to testify before the congressional
Joint Committee on Atomic Energy, as to how the
exponential increase in
strontium-90 in baby teeth caused by bomb-test fallout was associated with
increased childhood leukemia. His research and testimony played a role in
President Kennedy's decision to sign the Partial Test Ban Treaty.
His 1981 book Secret Fallout: Low-level Radiation from Hiroshima to
Three Mile Island established him as a pioneer in the study of the health
effects of low-level radiation
Strontium-90 is considered to be the most hazardous bone-seeking element created in the fission of uranium or plutonium because of its long half life of 28 years and because it resembles calcium so closely. By masquerading as calcium needed to form bone and teeth, it is readily taken up and concentrates in bone. In a pregnant woman, the Strontium-90 that has accumulated in the bone together with that in her diet is transported with calcium into the rapidly dividing cells of the embryo and fetus, where it can either kill or mutate them by the emission of high energy electrons or beta particles.
When Strontium-90 lodges near the bone marrow where stem-cells form blood and immune system cells, there is an increased risk of leukemia, many other forms of cancer and autoimmune diseases, especially in newborn infants and elderly adults whose immune system functions are weak.
[..]
Aside from the dose due to Strontium-90, it is an indicator of other radiation doses received from the many shorter-lived fission products that are produced together with Strontium-90 and released from nuclear reactors both in liquid and airborne effluents that do not rise high into the atmosphere.
[..]
Stokke, T., Oftedal R, and Pappas A. Effects of Small Doses of Strontium-90 on the Rat Bone Marrow. Acta Radiologica 7: 321, 1968.
The authors found that extremely small radiation doses by Strontium-90 in laboratory animals comparable to that from a month or two from natural background sources produced significant declines in the number of bone-marrow cells. This weakens the immune system and thus allows cancer cells anywhere in the body to proliferate more rapidly, and also causes infectious diseases to take a greater toll.