Is there any radioactive element in our body? If yes, is it harmful to us?

Question

Is there any radioactive element in our body? If yes, is it harmful to us?

Answer 1

fire is particularly dangerous. water can be also in large amounts. you probably only have to worry about earth if your in an area that gets a lot of earthquakes.

Answer 2

Glossary

Absorbed Dose - See "Dose"



Acoustic Energy - Mechanical energy transported by an acoustic wave. The units are those of acoustic power times time.



Acoustic Impedance - A vector quantity formed by taking the ratio of the instantaneous acoustic pressure at the surface to the instantaneous volume velocity at the surface in an acoustic field.



Acoustic Impedance Mismatch - A condition of unequal characteristic acoustic impedances of contiguous media, causing reflection of acoustic energy at the interface.



Acoustics - The science of sound, including its production, transmission and effects.



Activation - The process of making a material radioactive by bombardment with neutrons, protons, or other nuclear radiation.



Activity - A radiation quantity describing the number of atoms decaying in a given amount of radioactive material per unit time (also referred to as the rate of decay). The unit of measure is the curie (Ci) or the becquerel (Bq).



Acute Exposure - A large exposure (typically greater than 10 rads) received over a short period of time (acutely).



Acute Radiation Syndrome - See "Syndrome"



Agreement State - Any state in the United States where the USNRC has agreed that the state can perform the USNRC regulatory functions relative to the licensing and control of radioactive material used or produced within that state.



Airborne Contamination - The term applied to radioactive contamination loose in the air, filtered (trapped) from the air, or deposited from the air, as contrasted with contamination spread by splashing, dripping, etc.



ALARA - An acronym standing for "as low as is reasonably achievable". The term refers to an operating philosophy in which occupational exposures are reduced as far below specified limits as can be justified, with societal and economic factors taken into account.



Alpha Particle - A positively charged (+2) particle emitted from the nucleus of an atom. It is identical to a helium nucleus, that is, it has two protons and two neutrons (but no atomic electrons).



Ancillary - Supplementary.



Annihilation - A process converting mass into energy whereby a positron (positive beta particle) and an electron (negative beta particle) interact, causing the particles to disappear and their masses to convert into energy (two 0.511million electron volt (MeV) photons).



Anode - One of two electrodes present in radiation instrumentation that is positively charged with respect to the cathode, and is therefore used to collect negatively charged electrons produced through the ionization process.



Appraisal - A comprehensive evaluation of the overall adequacy and effectiveness of a radiation protection program.



Atom - The smallest unit of an element.



Atomic Number - The number of protons in the nucleus of an atom. The atomic number is also called the Z-number.



Background Radiation - The radiation in the natural environment, including cosmic rays and radiation from the naturally occurring radioactive elements, both outside and inside the bodies of humans and animals.



Backscatter - A charged particle interaction undergone by beta particles whereby the beta impacts on a surface and is scattered backwards through an angle greater than 90 degrees. Backscatter increases with increasing energy of the beta particle and atomic number of the surface medium.



Beta Particle - A charged particle emitted from a nucleus during radioactive decay. A negatively charged beta particle is identical to an electron. A positively charged beta particle is called a positron.



Becquerel - The basic unit of radioactivity in the International System of Units (SI System). The becquerel, abbreviated Bq, is equivalent to one radioactive atom disintegrating in one second (one disintegration per second). There are 37 billion Bq in one curie of radioactivity.



Bioassay - The collection and analysis of human tissue or byproducts (hair, tissue, nasal smears, urine or fecal samples) to determine the amount of radioactive material that might have been ingested by the body, or, alternatively, the direct assessment of radioactivity in the body utilizing external measurements.



Black Body - An ideal body that is in thermal equilibrium with the electromagnetic energy incident upon it. It behaves as if the incident energy is completely absorbed. The electromagnetic energy radiated by such a body in each spectral region is the maximum obtainable from any body at the same temperature.



Breathing Zone Samplers - Air sampling devices designed to be positioned close to an occupational worker's face in order to collect a sample representative of the air the worker is breathing.



Bremsstrahlung - The emission of photon radiation occurring when charged particles (principally beta and high energy electron radiations) interact with other atoms. Bremsstrahlung is also known as "braking radiation".



Byproduct Material - A term referring to material that becomes radioactive through the process of producing special nuclear material.



Calibration - The determination of a measuring instrument's ability to respond accurately to a source of radiation or radioactive contamination.



Cathode - One of two electrodes in a radiation detection device, negatively charged with respect to the anode, which collects positively charged ions produced through the ionization process.



Cathode Ray Tube (CRT) - An electron beam tube designed for two-dimensional display of signals as a function of their coordinates in space, time or both. It typically consists of an electron source (gun), a means of deflecting the electronic beam in the "x" and "y" directions, and a phosphorous screen upon which the position of the electron beam is visible.



Cavitation (Acoustically-induced) - A phenomenon produced by sound in liquid or liquid-like media involving bubbles or cavities containing gas or vapor.



Certified Health Physicist - An individual who has been Certified in the practice of health physics by the American Board of Health Physics. A Certified Health Physicists may be referred to as a "CHP", or as a "Diplomat of the American Board of Health Physics". CHPs are typically members in good standing of the American Academy of Health Physics.



CHP - See "Certified Health Physicist"



Chronic Exposure - Small radiation exposures received over a long period of time.



Compton Effect - One of three principal photon interactions with matter in which the photon imparts some of its energy to an electron orbiting the nucleus. The electron is subsequently ejected from the atom along with the photon.



Controlled Area - An area that a licensee establishes to limit access to radiation sources.



Contamination - The deposition of unwanted radioactive material in any place where it is not desired (e.g., on the surfaces of structures, areas, objects, or personnel).



Contamination Control - The process of minimizing the creation and spread of contamination.



Contamination Survey - A survey, often performed utilizing portable instrumentation, to detect the presence of radioactive material.



Cosmic Radiation - Penetrating ionizing radiation, composed primarily of charged particles of very high energies, originating in space.



Cosmogenic Radionuclides - Radionuclides produced by the interaction of cosmic radiations with the earth's atmosphere. Carbon-14 and Hydrogen-3 (tritium) are two well-known examples.



Count - The response of a device designed to detect ionizing radiation events. It may refer to a single detected event or to the total number of events registered in a given period of time. The term is often used erroneously to designate a disintegration, ionizing event, or voltage pulse.



Cross-contamination - Contamination not from an original source, but acquired from another contaminated object.



Curie - The conventional unit of radioactivity. The curie, abbreviated Ci, is equal to 37 billion nuclear disintegrations per second.



CW Laser - Continuous-wave laser, as distinguished from a pulsed laser. A laser emitting for a period in excess of 0.25 second.



Daughter - Synonym for decay product or progeny.



Decay, Radioactive - The disintegration of the nucleus of an unstable nuclide by the spontaneous emission of charged particles and/or photons.



Decay Series - The sequence of radioactive decays, each creating a new radioactive element, that the original radioactive element (the series parent) must undergo to achieve stability.



Decibel - A unit used for expressing the ratio of two like quantities, such as electrical signal amplitudes or sound energies.



Decontamination - The reduction or removal of radioactive contamination from a given surface.



Delayed Effect - An effect arbitrarily defined as occurring more than two months (often years) following an acute or chronic exposure. Delayed effects include solid cancers, leukemia, and genetic effects.



Detector, Radiation - Any device for converting radiant energy to a form more suitable for observation. An instrument used to determine the presence, and sometimes the amount, of radiation.



Doppler Effect - A shift in observed frequency (and wave length) caused by relative motions among sources, receivers, and the propagation medium when there is a component of relative motion parallel to the beam axis.



Dose - The radiation quantity describing the amount of ionizing radiation (or energy) deposited in a given mass of material. The term dose is also referred to as the "absorbed dose". Dose has units of rads or grays.



Dose Equivalent - The product of the dose (in rads or grays) and the quality factor. The dose equivalent is the quantity which utilizes the quality factor to account for the biological effectiveness of the different radiation(s) under consideration. The

Answer 3

how do u expect anyone in their right state of mind to read such a lengthy answer?

anyways, radioactivity is a part of our life , we are exposed to radioactivity from space though those rays are not very harmful. i guess we do have some radioactive element in our body but surely it not harmful, coz i never heard of ppl having troubles because of it.

Answer 4

yes

depends wat the element is and if its natural or foreign

Answer 5

yes

No

Answer 6

Radioactivity is a part of our earth - it has existed all along. Naturally occurring radioactive materials are present in its crust, the floors and walls of our homes, schools, or offices and in the food we eat and drink. There are radioactive gases in the air we breathe. Our own bodies - muscles, bones, and tissue - contain naturally occurring radioactive elements.



Man has always been exposed to natural radiation arising from the earth as well as from outside the earth. The radiation we receive from outer space is called cosmic radiation or cosmic rays.



We also receive exposure from man-made radiation, such as X-rays, radiation used to diagnose diseases and for cancer therapy. Fallout from nuclear explosives testing, and small quantities of radioactive materials released to the environment from coal and nuclear power plants, are also sources of radiation exposure to man.



Radioactivity is the term used to describe disintegration of atoms. The atom can be characterized by the number of protons in the nucleus. Some natural elements are unstable. Therefore, their nuclei disintegrate or decay, thus releasing energy in the form of radiation. This physical phenomenon is called radioactivity and the radioactive atoms are called nuclei. The radioactive decay is expressed in units called becquerels. One becquerel equals one disintegration per second.



The radionuclides decay at a characteristic rate that remains constant regardless of external influences, such as temperature or pressure. The time that it takes for half the radionuclides to disintegrate or decay is called half-life. This differs for each radioelement, ranging from fractions of a second to billions of years. For example, the half-life of Iodine 131 is eight days, but for Uranium 238, which is present in varying amounts all over the world, it is 4.5 billion years. Potassium 40, the main source of radioactivity in our bodies, has a half-life of 1.42 billion years.



Types of Radiation



The term "radiation" is very broad, and includes such things as light and radio waves. In our context it refers to "ionizing" radiation, which means that because such radiation passes through matter, it can cause it to become electrically charged or ionized. In living tissues, the electrical ions produced by radiation can affect normal biological processes.



There are various types of radiation, each having different characteristics. The common ionizing radiations generally talked about are:



Alpha radiation consists of heavy, positively charged particles emitted by atoms of elements such as uranium and radium. Alpha radiation can be stopped completely by a sheet of paper or by the thin surface layer of our skin (epidermis). However, if alpha-emitting materials are taken into the body by breathing, eating, or drinking, they can expose internal tissues directly and may, therefore, cause biological damage.

Beta radiation consists of electrons. They are more penetrating than alpha particles and can pass through 1-2 centimetres of water. In general, a sheet of aluminum a few millimetres thick will stop beta radiation.

Gamma rays are electromagnetic radiation similar to X-rays, light, and radio waves. Gamma rays, depending on their energy, can pass right through the human body, but can be stopped by thick walls of concrete or lead.

Neutrons are uncharged particles and do not produce ionization directly. But, their interaction with the atoms of matter can give rise to alpha, beta, gamma, or X-rays which then produce ionization. Neutrons are penetrating and can be stopped only by thick masses of concrete, water or paraffin.

Although we cannot see or feel the presence of radiation, it can be detected and measured in the most minute quantities with quite simple radiation measuring instruments.



Radiation Dose



Sunlight feels warm because our body absorbs the infra-red rays it contains. But, infra-red rays do not produce ionization in body tissue. In contrast, ionizing radiation can impair the normal functioning of the cells or even kill them. The amount of energy necessary to cause significant biological effects through ionization is so small that our bodies cannot feel this energy as in the case of infra-red rays which produce heat.



The biological effects of ionizing radiation vary with the type and energy. A measure of the risk of biological harm is the dose of radiation that the tissues receive. The unit of absorbed radiation dose is the sievert (Sv). Since one sievert is a large quantity, radiation doses normally encountered are expressed in millisievert (mSv) or microsievert (µSv) which are one-thousandth or one millionth of a sievert. For example, one chest X-ray will give about 0.2 mSv of radiation dose.



On average, our radiation exposure due to all natural sources amounts to about 2.4 mSv a year - though this figure can vary, depending on the geographical location by several hundred percent. In homes and buildings, there are radioactive elements in the air. These radioactive elements are radon (Radon 222), thoron (Radon 220) and by products formed by the decay of radium (Radium 226) and thorium present in many sorts of rocks, other building materials and in the soil. By far the largest source of natural radiation exposure comes from varying amounts of uranium and thorium in the soil around the world.



The radiation exposure due to cosmic rays is very dependent on altitude, and slightly on latitude: people who travel by air, thereby, increase their exposure to radiation.



We are exposed to ionizing radiation from natural sources in two ways:



We are surrounded by naturally-occurring radioactive elements in the soil and stones, and are bathed with cosmic rays entering the earth's atmosphere from outer space.





We receive internal exposure from radioactive elements which we take into our bodies through food and water, and through the air we breathe. In addition, we have radioactive elements (Potassium 40, Carbon 14, Radium 226) in our blood or bones.

Additionally, we are exposed to varying amounts of radiation from sources such as dental and other medical X-rays, industrial uses of nuclear techniques and other consumer products such as luminized wrist watches, ionization smoke detectors, etc. We are also exposed to radiation from radioactive elements contained in fallout from nuclear explosives testing, and routine normal discharges from nuclear and coal power stations.



Radiation Protection



It has long been recognized that large doses of ionizing radiation can damage human tissues. Over the years, as more was learned, scientists became increasingly concerned about the potentially damaging effects of exposure to large doses of radiation. The need to regulate exposure to radiation prompted the formation of a number of expert bodies to consider what is needed to be done. In 1928, an independent non-governmental body of experts in the field, the International X-ray and Radium Protection Committee was established. It later was renamed the International Commission on Radiological Protection (ICRP). Its purpose is to establish basic principles for, and issue recommendations on, radiation protection.



These principles and recommendations form the basis for national regulations governing the exposure of radiation workers and members of the public. They also have been incorporated by the International Atomic Energy Agency (IAEA) into its Basic Safety Standards for Radiation Protection published jointly with the World Health Organization (WHO), International Labour Organization (ILO), and the OECD Nuclear Energy Agency (NEA). These standards are used worldwide to ensure safety and radiation protection of radiation workers and the general public.



An intergovernmental body was formed in 1955 by the General Assembly of the United Nations as the UN Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). UNSCEAR is directed to assemble, study and disseminate information on observed levels of ionizing radiation and radioactivity (natural and man-made) in the environment, and on the effects of such radiation on man and the environment.



Basic approaches to radiation protection are consistent all over the world. The ICRP recommends that any exposure above the natural background radiation should be kept as low as reasonably achievable, but below the individual dose limits. The individual dose limit for radiation workers averaged over 5 years is 100 mSv, and for members of the general public, is 1 mSv per year. These dose limits have been established based on a prudent approach by assuming that there is no threshold dose below which there would be no effect. It means that any additional dose will cause a proportional increase in the chance of a health effect. This relationship has not yet been established in the low dose range where the dose limits have been set.



There are many high natural background radiation areas around the world where the annual radiation dose received by members of the general public is several times higher than the ICRP dose limit for radiation workers. The numbers of people exposed are too small to expect to detect any increases in health effects epidemiologically. Still the fact that there is no evidence so far of any increase does not mean the risk is being totally disregarded.



The ICRP and the IAEA recommend the individual dose must be kept as low as reasonably achievable, and consideration must be given to the presence of other sources which may cause simultaneous radiation exposure to the same group of the public. Also, allowance for future sources or practices must be kept in mind so that the total dose received by an individual member of the public does not exceed the dose limit.



In general, the average annual dose received by radiation workers is found to be considerably lower than the individual dose limits. Good radiation protection practice can thus result