Cancer treatment radium

The elements Ca, Sr, Ba and Ra are collectively known as the alkaline earth metals. We shall have little to say about radium it is radioactive and is formed as (a-emitter, h = 1622yr) in the decay series. Uses of radium-226 in cancer treatment have generally been superseded by other radioisotopes. The properties of radium and its compounds can be inferred by extrapolation from those of corresponding Ca, Sr and Ba compounds. 

Radium chloride, with the molecular formula of RaClj, is a yellowish-white crystal that becomes yellow or pink upon standing. It is radioactive and soluble in water. It is used in cancer treatment and physical research. 

Marie Curie s Radium Institute at the east end of the Rue Pierre Curie in the Latin Quarter, built just before the war with funds from the French government and the Pasteur Foundation, had the advantage in any studies that required polonium. Radon gas decays over time to three only mildly radioactive isotopes lead 210, bismuth 210 and polonium 210, which thus become available for chemical separation. Medical doctors throughout the world then used radon sealed into glass ampules— seeds —for cancer treatment. When the radon decayed, which it did in a matter of days, the seeds no longer served. Many physicians sent them on to Paris as a tribute to the woman who discovered radium. They accumulated to the world s largest source of polonium. 

Radon ( Rn) is the dominant source of human exposure to ionizing radiation in every country of the world. It is dominant in most circumstances at home and at work, for individual persons and for whole populations. The worst characteristic of radon, apart from its carcinogenicity, is its ubiquity. Before radon became a matter of concern for human exposure, it was studied and measured for many purposes. It was an inert tracer for air masses, it was a geological indicator for radium and uranium, and it was a shortlived source of y-radiation for cancer treatment. Radon plus beryllium was used as neutron source by Fermi for the discovery of neutron-induced fission reactions. 

His job was to sell off an inventory of radium, a byproduct of uranium, accumulated during the Second World War when Canada was the chief supplier of uranium for the allies. Radium was injected into cancer tumors to kill them. But Errington began pursuing other peacetime uses for the atom such as cancer treatment beds and the irradiation of medical products and food for sterilization. 

Radiums most important use is as a source of radiation in industry, medicine, and laboratories. The isotope radium-226, which is the most abundant of all the 25 isotopes and has a half-life of 1630 years, is the only useful form of the element. It is used in the medical treatment of malignant cancer growth. It kills cancer cells that have spread throughout the body. 

Uranium has been known to be a distinct element since 1789. Apart from the small amount of its salts used in yellow pottery glazes, however, it remained more or less a laboratory curiosity until the 1920s. Then, the treatment of uranium ore, for the recovery of its radium (for the treatment of cancer), began in Eastern Europe and Zaire, followed by Canada in 1933. The separated uranium was mostly stockpiled or discarded. 

In general, the adverse effects of radium are believed to be the consequence of the radiation emitted from the element itself and its daughter products. Because there is already a considerable amount of information on the effects of radiation on humans and animals derived from studies on the effects of the atomic bomb and of therapeutic x-ray and gamma-ray treatments of malignancies, the experimental animal studies with radium have made no attempt to duplicate this information. They have instead concentrated on radium s most sensitive endpoint, cancer. For example, it can be predicted that the beta and gamma rays emitted by a radium source will produce local radiation burns and tissue damage when the source is placed on human or animal skin, hence there have been no valid reasons to conduct such studies with radium. 

Radiation—the energy particles released by radioactive elements—can be a friend or foe to the human body. As The Radium Girls discovered, radiation can destroy cells and change the DNA in cells in a way that increases the risk of cancer. Yet radiation therapy is also widely used as a treatment for cancer, because carefully targeted radiation can be used to kill cancer cells. 

In addition to its many uses in medical and physiological research, radioisotopes are used in therapy, and in agricultural and industrial research. Radioactive cobalt, for example, became available for the treatment of deep-seated cancer. This isotope of atomic weight 60 loses half its radioactivity in about five days and is more than 300 times as powerful as radium. It is taking the place of radium and X-ray therapy in many hospitals. 

Krypton, Xenon, and Radon. Krypton and xenon, which occur in very small quantities in the air, have not found any significant use. Radon, which is produced steadily by radium, is used in the treatment of cancer. It has been found that the rays given off by radioactive substances are effective in controlling this disease. A convenient way ol administering this radiation is to pump the radon that has been produced by a sample of radium into a small gold tube, which is tlien placed in proximity to the tissues to be treated. 

Natural radioactivity. Discovery by Becquerel, Isolation of polonium and radium from pitchblende, by the Curies. Alpha rays, beta rays, gamma rays. Effect of a magnetic field on these rays. Use of radium and other radioactive elements in the treatment of cancer. 

Intentional uses of radium today are primarily in the treatment of cancer using a radiation source and as a neutron source in research and instrument calibration. Earlier uses of radium in paints and as a treatment for other illnesses and health-rejuvenating tonics were halted after its toxicity was recognized (see below). 

Before radiums dangerous radioactive properties were understood, it was used to make paints for watches and clocks that could be seen in the dark. Currently, radium is used in medical facilities like hospitals and other treatment centers to produce a radioactive gas called radon, which is used to treat cancer patients. 

Radium 223 is promising in the treatment of bone cancer, as it has only a half-life of 11 days, short half-lives of all daughter isotopes, and produces multiple alpha particles per decay. It is now marketed in the chemical form 223RaCl2. 

This shared electronic configuration has a more pragmatic importance in medicine. The similarity in electron shells allows strontium, barium, and radium to be absorbed in the same way as calcium in human and animal physiology—a phenomenon that leads to both a cause and a treatment for cancer. 

Stenbeck makes the first therapeutic treatment with radium and heals skin cancer. Rutherford, Geiger, and Marsden conclude from measurement of the scattering of a-radiation against thin foils that atoms contain a very small positive nucleus. 

Such systems are called radioisotope generators. Rn is sometimes used for the radiotherapeutic treatment of cancer. This product is isolated by separating it as a gas from the parent substance Ra which is normally in the form of solid or a solution of RaBr2. Rn grows into the radium sample with a half-life of 3.8 d. After a 2-week period, following a separation of radon from radiiun, approximately 90% of the maximum amount of radon has grown back in the radium sample. Consequently, it is useful to separate Rn each 2 weeks from the radium samples since further time provides very little additional radioactivity. The Rn is an a emitter the ther utic value comes from the irradiation of the tissue by the y-rays of the decay daughters Pb and Bi which reach radioactive uilibrium extremely rapidly with the Rn. 

The uranium decay series provides the most important isotopes of elements radium, radon, and polonium, which can be isolated in the processing of uranium minerals. Each ton of uranium is associated with 0.340 g of Ra. Freshly isolated Ra reaches radioactive equilibrium with its decay products to Pb in about two weeks (see Fig. 1.2). Many of these products emit energetic y-rays, which resulted in the use of Ra as a y-source in medical treatment of cancer (radiation therapy). However, the medical importance of radium has diminished greatly since the introduction of other radiation sources, and presently the largest use of radium is as small neutron sources (see Table 12.2). 

It is used in the medical treatment of malignant growths and industrial radiography. Compounds formed with radium all have the same hazards as radium itself. Most are used in the treatment of cancer and for radiography in the medical and industrial fields. The compounds are all solids, and the degree of water solubility varies. Radium bromide has a molecular formula of RaBr2 it is composed of white crystals that turn yellow to pink. It sublimes at about 1650jF and is water-soluble. The hazards are the same as for radium. It is used in the medical treatment of cancers. 

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