Definition
An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
Description
Potassium-40 is a naturally occurring radioactive isotope of potassium. Potassium is the chemical element with the symbol K and atomic number 19. Potassium is widely distributed in nature and is present in all plant and animal tissues. Potassium-40 comprises about 0.012% of naturally occurring potassium. It is the predominant radioactive component in human tissues and in most food. Potassium-40 has a half-life of 1.3 billion years and emits beta and gamma radiation. (L1134, L1851)
Top Gene Interactions
Related Pathways
Potassium Health Effects
General Information
- Metabolism: Potassium-40 behaves in the body in the same manner as other potassium isotopes. Potassium is almost completely absorbed upon ingestion, moving quickly from the gastrointestinal tract to the bloodstream. The potassium-40 that enters the bloodstream after ingestion or inhalation is quickly distributed to all organs and tissues. Potassium-40 is eliminated from the body with a biological half-life of 30 days. The potassium content of the body is under strict homeostatic control (in which the amount retained is actively regulated by the body to achieve the normal range required for system functions), and it is not influenced by variations in environmental levels. Hence, the potassium-40 content in the body is constant, with an adult male having about 0.1 microcurie or 100,000 pCi. Each year this isotope delivers doses of about 18 millirem (mrem) to soft tissues of the body and 14 mrem to bone. Potassium cations are important in neuron function, influencing osmotic balance between cells and the interstitial fluid, allowing muscle contraction and the sending of all nerve impulses through action potentials, and maintaining fluid and electrolyte balance in the body. (L1134, L1851)
- Uses/Sources: There are no specific commercial or medical uses associated with the radioactive properties of potassium-40. (L1134)
- Health Effects: Potassium-40 presents external as well as internal health hazard. The strong gamma radiation makes external exposure to this isotope a concern. While in the body, potassium-40 poses a health hazard from both the beta particles and gamma rays. The health hazard of potassium-40 is associated with cell damage caused by the ionizing radiation that results from radioactive decay, with the general potential for subsequent cancer induction. (L1134)
- Symptoms: Exposure to high doses of ionizing radiation results in acute radiation syndrome, which can cause skin burns, hair loss, nausea, vomiting, dizziness, disorientation, low blood pressure, headache, fatigue, weakness, fever, birth defects, illness, infection, and death. (L1837, L1852)
- Treatment: Treatment reversing the effects of irradiation is currently not possible. Anaesthetics and antiemetics are administered to counter the symptoms of exposure, as well as antibiotics for countering secondary infections due to the resulting immune system deficiency. (L1852)
- Route of Exposure: Oral (L1134) ; inhalation (L1134)
Mechanism of Action
| Target Name | Mechanism of Action | References |
|---|---|---|
| Sodium/potassium-transporting ATPase subunit alpha-1 |
17369284 17444965 17366541 17347782 17334838 |