radguide

37 Radiation for Radionuclide Users Internal Radiation Protection Any radionuclide, whether it is an alpha, beta, or gamma emitter, poses a potential hazard to health if incorporated into the body. Once within the body, the radionuclide will continue to irradiate living tissue until it is removed by natural processes. Because there is no easy way of increasing the rate of these processes, it is essential that radionuclides be prevented from being taken into the body in the first place. In order to adequately protect against the uptake of radionuclides, it is important to understand the ways in which radionuclides enter the body. The four primary routes of uptake are: (1) ingestion; (2) inhalation; (3) absorption through the skin; (4) injection. Protection Against Ingestion By far the most common route of uptake of radionuclides is ingestion. Incorporation of radionuclides into the body by this pathway generally results from the researcher eating, drinking, or smoking with contaminated hands. This serves to emphasize the importance of observing strict contamination control measures in the laboratory including the monitoring of hands, clothing, and work areas after each procedure involving the use of radioactive material and the washing of hands before leaving the laboratory.. Protection Against Inhalation Certain chemical forms of particular radionuclides volatilize easily and thus pose a hazard through inhalation. Examples of these include tritiated water and radioiodines in solution as NaI. Because of the volatility of these materials, procedures involving their use should always be carried out within a fume hood. Protection Against Absorption Many of the same types of radioactive materials that pose inhalation hazards also pose a hazard by absorption through the skin. Both tritiated water and various chemical forms of radioiodine are readily absorbed through the skin. In addition, such materials have been shown to diffuse fairly quickly through the thickness of a single rubber glove. For this reason, it is important that two pairs of gloves be worn and that the outer pair be changed frequently during procedures using these materials. Protection Against Injection Accidental puncture with contaminated syringes or other “sharps” is also a common route of uptake of radioactive material as well as biologically and chemically hazardous materials. For this reason, extra care should be practiced during manipulations or transfers