Cobalt is a natural element found in rocks, in soil, in water, in plants and in animals. Cobalt is used in the manufacture of alloys for applications in aircraft engine construction, in magnets, in grinding and cutting tools, in hip and knee joints. Cobalt compounds are used in colored glass, ceramics and paints as well as in porcelain. Radioactive cobalt is used for commercial and medical purposes. 60Co is used in the sterilization of medical equipment and certain consumer products, in radiation therapy to treat cancer patients, in the manufacture of plastics and in the irradiation of foods. 57Co is used in medicine and research. It takes about 5.3 years to halve 60Co radiation and about 272 days for 57Co (this time is called half-life).
The general population is exposed to low levels of cobalt through air, water and food. Cobalt has both beneficial and harmful effects on health. At low levels, it is a part of vitamin B12, which is essential for the proper functioning of the body. At high concentrations it can damage the lungs and heart.
How does cobalt enter the environment?
- Cobalt enters the environment from natural sources and from the combustion of coal and oil and the production of cobalt alloys.
- In the air cobalt binds to particles, settling in the ground within a few days.
- Cobalt released into the water or into the soil is bound to particles. Some cobalt compounds may be soluble in water.
- Cobalt cannot be destroyed. It can be reshaped or bound or separated from the particles. Radioactive decay is one way of reducing the amount of cobalt in the environment.
How is one exposed to Cobalt?
- One may be exposed to low levels of cobalt by breathing air, eating food or drinking water. Food and drinking water are the major sources of exposure for the general population.
- Workers in industries manufacturing or using cutting or grinding tools, in mines, in factories producing and processing cobalt alloys or using cobalt.
- The general population is rarely exposed to radioactive cobalt unless irradiated. However, nuclear plant workers, irradiation facilities or nuclear waste storage sites may be exposed to radiation from these sources.
How can cobalt affect health?
Cobalt can benefit or harm human health. Cobalt is essential for the metabolism of all animals. It is an essential ingredient of cobalamin, known as vitamin B12, the primary biological reservoir of cobalt in the body as a super-trace element. Bacteria in the gut of ruminant animals convert cobalt salts to vitamin B12, a compound that can only be synthesized by bacteria or archaebacteria. Cobalt's minimal presence in soils significantly improves the health of grazing animals because they have no other source of vitamin B12. The use of cobalt in the two biologically active forms of cobalamin, adenosyl cobalamin and methyl cobalamin, is the only known function of this metal in biological systems.
However, chronic ingestion of cobalt causes serious health problems at doses much less than the lethal dose. In 1966, the addition of cobalt compounds to stabilize beer foam in Canada resulted in the appearance of toxic myocardial infarction in regular beer drinkers, which became known as "beer drinker heart disease".
Exposure to high levels of cobalt can lead to lung and heart damage and dermatitis. After nickel and chromium, cobalt is the most important cause of contact dermatitis. Effects on the liver and kidneys have also been observed in experimental animals exposed to high levels of cobalt.
Exposure to high levels of radiation from radioactive cobalt can damage the cells of the body. It can also cause Acute Radiation Syndrome which includes nausea, vomiting, diarrhea, bleeding, coma and even death.
Non-radioactive cobalt has not been found to cause cancer in humans or animals through exposure to food and water. However, cancer has been shown in cobalt-breathing animals or when cobalt was placed directly into the muscle or under the skin. Cobalt and its compounds are probably carcinogenic to humans.
Exposure to high levels of cobalt radiation can cause changes in the genetic material of the cells and can lead to the development of certain types of cancer.
Special metal ions are required for the activity of many enzymes. Some metal ions increase the enzyme activity and others decrease or even inhibit it. Metals such as calcium, cobalt, copper, iron, magnesium, manganese, molybdenum, potassium and zinc are the most common enzymatic activators. Some heavy metal ions such as barium, lead and mercury inhibit enzymatic reactions because they bind to the sulfhydryl (-SH) group which forms part of the active site of many enzymes.
How can the risk of exposure to cobalt be reduced?
Children should avoid playing in terrain near hazardous waste areas where cobalt may be present.
How can one determine if one has been exposed to cobalt?
Cobalt levels can be detected in urine and blood within two days of exposure. Cobalt concentration in blood or urine can be used to evaluate exposure to cobalt.
There are two types of tests for cobalt. One type is used to determine whether there is exposure to radiation and the other to determine whether cobalt is present in the body. The first type of test looks for changes in blood cells or chromosomes but cannot determine whether the radiation originates from cobalt. The second type of tests includes blood, stool, urine, saliva tests to determine whether cobalt has been excreted or remains in the body.
We can measure cobalt levels in blood and most biological materials.
Determination of metals is done by ICP-MS (Inductively Coupled Plasma Mass Spectrometry, Inductively Coupled Argon Plasma Mass Spectrometry), a method that enables the simultaneous detection of many metals. Its sensitivity and accuracy are significantly better than conventional atomic absorption, with the ability to measure metals at concentrations up to 1 in 1015 (1 in 1 quadrillion, ppq)!
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. Correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.