Strontium from nuclear fallout

Strontium-90 pollutes water and soil at some reprocessing plants. Atmospheric contamination can occur from nuclear fallout. A study in the United States has concluded that high concentrations of strontium in eggshells of some passerine birds may be associated with lower hatching success. 

The radiation hazard associated with fallout from nuclear weapons testing arises from radioactive isotopes such as these. One of the most dangerous is strontium-90. In the form of strontium carbonate, SrC03, it is incorporated into the bones of animals and human beings, where it remains far a lifetime. 

Half-lives span a very wide range (Table 17.5). Consider strontium-90, for which the half-life is 28 a. This nuclide is present in nuclear fallout, the fine dust that settles from clouds of airborne particles after the explosion of a nuclear bomb, and may also be present in the accidental release of radioactive materials into the air. Because it is chemically very similar to calcium, strontium may accompany that element through the environment and become incorporated into bones once there, it continues to emit radiation for many years. About 10 half-lives (for strontium-90, 280 a) must pass before the activity of a sample has fallen to 1/1000 of its initial value. Iodine-131, which was released in the accidental fire at the Chernobyl nuclear power plant, has a half-life of only 8.05 d, but it accumulates in the thyroid gland. Several cases of thyroid cancer have been linked to iodine-131 exposure from the accident. Plutonium-239 has a half-life of 24 ka (24000 years). Consequently, very long term storage facilities are required for plutonium waste, and land contaminated with plutonium cannot be inhabited again for thousands of years without expensive remediation efforts. 

The name comes from the town of Strontian in Scotland and was given to the element by Thomas Hope (1766-1844). There are many claims for the original discovery of strontium. William Cruikshank, in 1787, and Adair Crawford, in 1790, both examined strontianite (SrC03) and recognized that it had unique properties. Thomas Hope noted an unknown earth in 1791. Martin Klaproth presented a paper on a number of strontium compounds in 1793 and 1794. Richard Kirwan (1733-1812) examined a number of strontium compounds and presented his findings in 1794. It was Davy who isolated strontium metal, in 1808. Strontium does not occur in pure form in nature but is found in small quantities in many places. Some forms of strontium are radioactive, particularly 90Sr, which has been found in nuclear fallout. It can also be used in SNAP devices (Systems for Nuclear Auxiliary Power) as a power source. The main commercial use of strontium is in the glass of color television picture tubes. 

The threat of nuclear fallout from atomic weapons testing was the impetus for a large number of studies that investigated methods to prevent absorption of radiostrontium, while not adversely affecting the absorption of calcium. Reasonably effective strategies have included alginates, aluminum phosphate, and sulfates. Less effective or less practical strategies have included cold, diet, dietary fiber, flavones, and stable strontium. 

Cesium-137 and strontium-90 from nuclear weapon fallout using tobacco as an example Z. Lebensm. 

Strontium-90 occurs in fallout from nuclear testing. It can accumulate in bone marrow and may cause leukemia and bone cancer. Give the number of protons, neutrons, and electrons in the atom symbolized by 3° Sr. 

Radioactive decay is first order in the decaying isotope. For example, strontium-90 contained in fallout from nuclear explosions decays to yttrium-90 and a beta particle. Write the rate law for the decay of strontium-90. 

Strontium-90 is also found in waste from nuclear reactors. It is considered one of the more hazardous constituents of nuclear wastes. The accident at the Chernobyl nuclear power plant al.so introduced a large amount of Sr-90 into the environment. A large part of the Sr-90 was deposited in the Soviet Republics. The rest was dispersed as fallout over Northern Europe and worldwide. No significant amount of stronium-90 reached the U.S. 

Summary.—We have developed methods of theoretical analysis of the results of experimental studies of the effects of injection of radioactive substances into animals on their life expectancy and on the incidence of tumors. These methods have been applied to the data reported for mice by Dr. Miriam P. Finkel, and it has been shown that her conclusion from these data that it is extremely unlikely that the strontium-90 from the fallout from nuclear weapons tests will induce even one bone tumor or one case of leukemia in human beings is completely unjustified. 

Strontium-90, 3gSr, is a radioactive decay product of nuclear fallout from nuclear weapons testing. Because of its chemical similarity to calcium, it is incorporated into the bones if present in food. The half-life of strontium-90 is 28.1 y. What is the decay constant of this isotope What is the activity of a sample containing 5.2 ng (5.2 X 10 g) of strontium-90 ... 

Cesium, strontium and plutonium have been detected in sediments of Ob and Enisey downstream as far as the mouths of the rivers and in Enisey floodlands. In some places contamination was higher than that from global fallout. Although nuclear military facilities in Siberia could be potential contributors to the radioactive contamination of the Arctic, global fallout onto the land seems predominant. Some part of radionuclides is washed into the rivers and ultimately transported to the Kara Sea. As the catchment area of the river Enisey is smaller than that of Ob , its contribution into the radioactive contmnination of the Arctic would be smaller [OTA, p. 45]. Potential contributions of the weapons complex to Arctic pollution depends on many factors, and permanent monitoring of the weapons production sites is necessary. 

Strontium-90, a radioactive strontium isotope with a half-hfe of 29 years, is a dangerous fallout source of radiation from atmospheric nuclear bombs. If a person is exposed to it, it will rapidly accumulate in bone tissue and interfere with the production of new red blood cells... 

Epidemiological studies of populations in the FSU exposed to fallout from the 1986 nuclear reactor explosion at Chernobyl and releases from the Chelyabinsk-65 complex demonstrate the health effects associated with exposure to radioactive iodine, strontium, and caesium. A study of 2.81 X 10" individuals exposed along the Techa River, downstream from Chelyabinsk-65, revealed that a statistically significant increase in leukemia mortality arose between 5 yr and 20 yr after the initial exposure (37 observed deaths versus 14-23 expected deaths see Cochran et al. (1993) and cited references and comments). There has been a significant increase of thyroid cancers among children in the areas contaminated by fallout from the Chernobyl explosion (Harley, 2001 UNSCEAR, 2000). The initial external exposures from Chernobyl were due to and short-lived isotopes. Subsequently, external exposures to Cs and nd internal... 

Strontium is a naturally occurring element found in rocks, soil, dust, coal, and oil. Naturally occurring strontium is not radioactive and is referred to as stable strontium. Stable strontium in the environment exists in four stable isotopes, " Sr (read as strontium 84), Sr, Sr, and Sr. Twelve other unstable isotopes are known to exist. Its radioactive isotopes are Sr and °Sr. Strontium is chemically similar to calcium. It was discovered in 1790. The isotope Sr is a highly radioactive poison, and was present in fallout from atmospheric nuclear explosions and is created in nuclear reactors. Atmospheric tests of nuclear weapons in the 1950s resulted in deposits and contaminations. °Sr has a half-life of 28 years and is a high-energy beta emitter. Its common cationic salts are water soluble it forms chelates with compounds such as ethylenediaminetetraacetic acid strontium coordination compounds are not common. Powdered metallic strontium may constitute an explosion hazard when exposed to flame. 

Calcium phosphate is the component of human bone that provides rigidity. Fallout from a nuclear bomb can contain radioactive strontium-90. These two facts are closely tied together when one considers human health. Explain. 

Calcium phosphate is the component of human bone that provides rigidity. Fallout from a nuclear bomb can contain radioactive strontium-90. These two facts are closely tied together when one considers human health. Explain. Limestone consists mainly of the mineral calcite, which is calcium carbonate. A very similar deposit called dolostone is composed primarily of the mineral dolomite, an ionic substance that contains carbonate ions and a mixmre of magnesium and calcium ions, (a) Is this a surprising mixture of ions Explain, based on the periodic table, (b) A test for limestone is to apply cold dilute hydrochloric acid, which causes the rapid formation of bubbles. What causes these bubbles ... 

On Sept. 19, 1958 there was published in Science a paper by Dr. Miriam P. Finkel of Argonne National Laboratory in which she communicated her observations on the effects of strontium-90 injected into mice on life expectancy and on incidence of tumors of bone and blood-forming tissues. She discussed the question of whether or not the effects are proportional to the amount of injected strontium-90 at low doses, and reached the conclusion that it is likely that there is a threshold with value for man between 5 and 15 /ic. (as compared with the present average value from fallout, about 0.0002 y-o,., and the predicted steady-state value from fallout for testing of nuclear weapons at the average rate for the past five years, about 0.02 yc.). Her paper ends with the sentence In any case, the present contamination with strontium-90 from fallout is so very much lower than any of these levels that it is extr nely unlikely to induce even one bone tumor or one case of leukemia. ... 

Strontium-90 isotopes are present in the fallout from atmospheric testing of nuclear weapons. Strontium is in the same periodic-table group as calcium, and its chemical behavior is similar to that of calcium. Hence when foods contaminated with Sr-90 are eaten, Sr-90 ions are laid down in the bone tissue along with ordinary calcium ions. Strontium-90 is a beta emitter with a half-life of 28 years. Blood cells manufactured in bone marrow are affected by the radiation from Sr-90. Hence there is concern that Sr-90 accumulation in the environment may cause an increase in the incidence of leukemia and bone cancers. 

Nuclear weapons present hazards in virtually all areas of their life cycle. Production and testing have their own impacts. The U.S. National Cancer Institute estimated that the release of iodine-131 in fallout from U.S. nuclear test explosions was by itself responsible for 49,000 excess cases of thyroid cancer among the U.S. popnlation [8]. A 1991 pubhcation by the hitemational Physicians for the Prevention of Nnclear War estimated that the strontium-90, cesium-137, carbon-14, and poloninm-239 released worldwide in all nuclear test explosions would be responsible for 430,000 cancer deaths by 2000 [9]. Additional widespread health and enviromnental effects of nuclear-weapons prodnction include massive contamination of land by radioactive materials and toxic chemicals. 

At one time, nuclear bombs were tested by exploding them above ground. The fallout from such tests contained some Sr-90, a radioactive isotope of strontium. If Sr-90 gets into the food supply, it can become incorporated into the bones of humans and other animals. Explain how this can happen even though strontium is not a normal component of bones. 

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