Cobalt cancer

Tnglycidyl isocyanurate, beryllium and beryllium compounds Cancer epidemiology m coal tar pitch volatile-associated industries Cobalt and cobalt compounds... 

Cobalt-60 cancer therapy. Gamma rays from the rotating radiation source are concentrated at the location of the diseased tissue. 

A neutron can get close to a target nucleus more easily than a proton can. Because a neutron has no charge and hence is not repelled by the nuclear charge, it need not be accelerated to such high speeds. An example of neutron-induced transmutation is the formation of cobalt-60, which is used in the radiation treatment of cancer. The three-step process starts from iron-58. First, iron-59 is produced ... 

In a different way, metallic-core nanoparticles [346-349] (prepared cf. Section 3.10) equipped with biocompatible coats such as L-cysteine or dextrane may be exploited for highly efficient and cell-specific cancer cell targeting, i.e., for improving diagnosis and therapy of human cancer. In a recent proof-of-principle experiment an unexpectedly low toxicity of the L-cysteine-covered cobalt nanoparticles was demonstrated [433] For diagnostic purposes, it is expected to use the advantageous magnetic properties of the metallic-core nanoparticles to obtain a contrast medium for MRI with considerably increased sensitivity, capable to detect micro-metastases in the environment of healthy tissues [434 37]. 

Common radioactive material in use today includes the alpha emitters Americium-241 and Plutonim-238 the beta emitters Phosporus-32 and Strontium-90 and the gamma emitters Cesium-137, Cobalt-60, and Iridium-192 [44], These materials are commonly used in smoke detectors, oil exploration, industrial gauges, food and mail irradiation, cancer therapy, industrial radiography, and in research laboratories. 

Cesium-137 is a highly useful radioisotope that emits its radiation at a very steady and controllable rate. This makes it useful as an atomic clock because it is extremely accurate and never needs winding or a new battery. It is also useful as a radiation source for treatment of malignant cancers. Cs-137 has replaced the much more dangerous cobalt-60 as a source of radiation in industry and medicine. 

The radioisotope cobalt-60, with a half-life of 5.27 years (1925.3 days) through beta ((3) emission, decays to form the stable element nickel-60. It is used to test welds and metal casts for flaws, to irradiate food crops to prolong freshness, as a portable source of ionizing gamma (Y) radiation, for radiation research, and for a medical source of radiation to treat cancers and other diseases. 

Cobaltous chromate (CoCrO ) is brownish-yellow to grayish-black (the color depends on its purity) is a dangerous carcinogen (causes cancer). 

Jensen AA, Tuchsen F Cobalt exposure and cancer risk. CRC Rev Toxicol 20 427M-37, 1990... 

Tuchsen F, Jensen MV, Villadsen E, et al Incidence of lung cancer among cobalt exposed women. ScandJ Work Environ Health 22(6) 444-450, 1996... 

Rare metal easily magnetized and used in the alloy alnico to make industrial magnets its isotope cobalt-60 produces radiation that is a treatment for cancer. 

Gilman JPW, Ruckerbauer GM. 1962. Metal carcinogenesis I Observations on the carcinogenicity of a refinery dust, cobalt oxide and colloidal thorium dioxide. Cancer Res 22 152-156. 

Gilman JPW. 1962. Metal carcinogenesis. 11. A study on the carcinogenic activity of cobalt, copper, iron and nickel compounds. Cancer Res 22 159-162. 

Radioisotopes are also used in radiation therapy to treat cancer. The goal in radiation therapy is to kill malignant cells, while protecting healthy tissue from radiation effects. Radioisotopes such as yttrium-90, a beta emitter, may be placed directly in the tumor. Alternatively, the diseased tissue may be subjected to beams of gamma radiation. Cobalt-60 used in radiation therapy is prepared by a series of transmutations ... 

Jackson and Adams studied 33 cases of extensive basal cell carcinoma, two of which involved mustard-gas burns sustained during World War I. One of those developed 35 yr after the burn, but 2 yr after irradiation with cobalt-60. In the other, basal cell carcinoma developed at the site of three separate burns, 3 yr after exposure. Some of the mustard burns did not lead to basal cell cancer. 

The damaging effects that radioactivity can have on tissues are not all bad. To treat cancers, we want to kill cells - albeit the unhealthy, frantically replicating tumour cells, not healthy cells. If radioisotopes can be localized in tumours, they do their destructive business to good effect. Cobalt-60, made by neutron bombardment of stable cobalt-59, is a radioisotope with a half-life of 5.3 years that is used to treat cancer. 

Medical x-rays provided one of the first applications of radioisotopes. In 1914, the wounded from World War 1 were pouring into Paris hospitals. Marie Curie converted a Renault car into the first mobile radiological unit and drove it from hospital to hospital. Radioisotopes are now widely used in medicine to diagnose, study, and treat illness. A physician can determine, for example, how and at what rate the thyroid gland takes up iodine by using iodine-131 as a radioactive tracer and cobalt-60 is used to kill rapidly growing cancer cells. 

A cobalt-60 source purchased for the radiation therapy of cancer patients has an activity of 1.20 Ci. What will the activity of the source be after 5.0 y ... 

Still other nuclear transmutations are carried out using neutrons, protons, or other particles for bombardment. The cobalt-60 used in radiation therapy for cancer patients can be prepared by neutron bombardment of iron-58. Iron-58 first absorbs a neutron to yield iron-59, the iron-59 undergoes j8 decay to yield cobalt-59, and the cobalt-59 then absorbs a second neutron to yield cobalt-60 ... 

Therapeutic Procedures Therapeutic procedures—those in which radiation is used to kill diseased tissue—can involve either external or internal sources of radiation. External radiation therapy for the treatment of cancer is often carried out with y rays from a cobalt-60 source. The highly radioactive source is shielded by a thick lead container and has a small opening directed toward the site of the tumor. By focusing the radiation beam on the tumor and rotating the patient s body, the tumor receives the full exposure while the exposure of surrounding parts of the body is minimized. Nevertheless, sufficient exposure occurs so that most patients suffer some effects of radiation sickness. 

Cancerous tumors can be treated by irradiation with y rays from this cobalt-60 source. 

Nackerdien Z, Kasprzak KS, Rao G, Halliwell B, Dizdaroglu M (1991) Nickel(II)- and cobalt(ll)-depen-dent damage by hydrogen peroxide to the DNA bases in isolated human chromatin. Cancer Res 51 5837-5842... 

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