Radioactive materials internal contamination

The key actions in protecting against the internal hazard are aimed at preventing the radioactive material from contaminating the working environment and individuals and, thus, from entering the body. 

Myttenaere, C., Bordeau, P. and Bittel, R. (1969a). Relative importance of water and soil in the indirect radiocaesium and radiocobalt contamination of irrigated rice fields, page 175 in Agricultural end Public Health Aspects of Environmental Contamination by Radioactive Materials, IAEA Publication No. STI/PUB/226 (International Atomic Energy Agency, Vienna). 

Internal contamination Though inhalation, ingestion or transdermal absorption, radioactive material is deposited into body tissues... 

Finally, any packaging or accessory which has been used for a shipment of radioactive materials and which contains residual internal radioactive contamination must, when shipped as empty, have an EMPTY label affixed to the packaging. 

Routes of entry for radioactive materials are much the same as for poisons. However, the radioactive source or material does not have to be directly contacted for radiation exposure to occur. Exposure occurs from the radiation being emitted from the radioactive source. Once a particulate radioactive material enters the body, it is dangerous because the source now becomes an internal source rather than an external one. You cannot protect yourself by time, distance, or shielding from a source that is inside your body. Contact with or ingestion of a radioactive material does not make you radioactive. Contamination occurs with radioactive particles, but with proper decontamination, these can be successfully removed. After they are removed, they cannot cause any further damage to the body. 

The radioanalytical chemistry laboratory is subject to all of these hazards with the addition of radioactive solids, liquids and gases. The potential risks to laboratory workers from radioactive materials include exposure to ionizing radiation, both from external sources and from internal sources that were inhaled, ingested, or absorbed through the skin. Contamination of the immediate work area is a safety concern that becomes amplified if the contamination is not removed promptly and is subsequently spread over a much wider area. Each of these hazardous situations may result from an unintended release or from improper handling of radioactive materials. Often, the person who is affected is not the one who caused the problem in the first place. 

People may become internally contaminated (inside their bodies) with radioactive materials by accidentally ingesting (eating or drinking) or inhaling (breathing) them. The sooner that these materials are removed from the body, the fewer and less severe the health effects of the contamination will be. Prussian blue is a substance that can help remove certain radioactive materials from people s bodies. However, Prussian blue currently is available only when doctors have determined that a person is internally contaminated. 

This amount of radioactive material, if dispersed, could possibly — although it would be unlikely — permanently injure or be hfe threatening to persons in the immediate vicinity. There would be httle or no risk of irrrmediate health effects to persons beyond a few hundred metres away, but contaminated areas would need to be cleaned up in accordance with international standards. For large sources the area to be cleaned up could be a square kilometre or more."... 

Contamination includes two types of radioactive material on surfaces or embedded in surfaces, namely fixed contamination and non-fixed contamination. There is no definitive distinction between fixed and non-fixed contamination, and various terms have been used to describe the distinction. For practical purposes a distinction is made between contamination which, during routine conditions of transport, remains in situ (i.e. fixed contamination) and, therefore, cannot give rise to hazards from ingestion, inhalation or spreading, and non-fixed contamination which may contribute to these hazards. The only hazard from fixed contamination is that due to external radiation exposure, whereas the hazards from non-fixed contamination include the potential for internal exposure from inhalation and ingestion as well as external exposure due to contamination of the skin should it be released from the surface. Under accident conditions, and under certain use conditions such as weathering, fixed contamination may, however, become non-fixed contamination. 

Conveyances may become contaminated during the carriage of radioactive material by the non-fixed contamination on the packages. If the conveyance has become contaminated above this level, it should be decontaminated to at least the appropriate limit. This provision does not apply to the internal surfaces of a conveyance provided that the conveyance remains dedicated to the transport of radioactive material or surface contaminated objects under exclusive use (see para. 514.1). 

The removal of radioactive material from a location where it is not desired. In regard to personnel it would include both removal of external contamination by washing and removal of internal contamination by the use of chelating agents or similar methods. Deductible, Insurance... 

The deposition or presence of radioactive material in a place where it is not desired and may be harmful. In regard to personnel there are two types of radioactive contamination external and internal. External radioactive contamination is the presence of radioactive material on the skin. Internal radioactive contamination is the presence of radioactive material within the body due to ingestion, inhalation, or absorption. Railings... 

Contamination (radioactive)— The deposit of unwanted radioactive material on the surfaces of structures, areas, objects, or people where it may be external or internal. 

This monitor is designed to monitor radioactive material deposited on clothes, shoes, and body surfaces of a worker in an isotope laboratory. Therefore, the device contains foot and hand detectors. It is usually posted at the exit of the laboratory. The purpose of the monitor is to avoid the spread of radioactive substances and to discover any internal contamination. 

Internal due to contamination with radioactive materials, if ingested, inhaled, or deposited in wounds. 

Exposure of a person may be external or internal and may be incurred by various exposure pathways (see Section 9.3). External exposure may be due to direct irradiation from the source, airborne radionuclides in the air (immersion or exposure to an overhead plume), or radionuclides deposited onto the ground and onto a person s clothing and skin. Internal exposure follows from the inhalation of radioactive material either directly from a plume or resuspended from contaminated surfaces, from the ingestion of contaminated food and water, or through contaminated wounds. Total effective dose can be calculated by taking into account all dominant exposure pathways by which persons were exposed. 

Being in the vicinity of radioactive source Ground contamination (e.g., from ruptured source) Material on the skin (e.g., from ruptured source) Internal exposure from Ingestion of contamination on hands sealed source... 

The cost-benefit comparison is a consideration that each radioactive material licensee and user must make for themselves. There is a large gray area in the middle where the benefit of a reduction in dose to the individual(s) must be weighed against the cost to the enterprise to implement it. When it comes to reducing external doses in accordance with AT.ARA principles, there are three major factors time, distance, and shielding. For reducing internal doses in accordance with ALARA principles, simple contamination control measures should be used. 

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