Body burden radiological

The radiological hazard of tritium to operating personnel and the general population is controlled by limiting the rates of exposure and release of material. Maximum permissible concentrations (MPC) of radionucHdes were specified in 1959 by the International Commission on Radiological Protection (79). For purposes of control all tritium is assumed to be tritiated water, the most readily assimilated form. The MPC of tritium ia breathing air (continuous exposure for 40 h/wk) is specified as 185 kBq/mL (5 p.Ci/mL) and the MPC for tritium in drinking water is set at 3.7 GBq/mL (0.1 Ci/mL) (79). The maximum permitted body burden is 37 MBq (one millicurie). Whenever bioassay indicates this value has been exceeded, the individual is withdrawn from further work with tritium until the level of tritium is reduced. 

Thomas SR, Maxon HR, Fritz KM, Kereiakes JG, Connell WD. A comparison of methods for assessing patient body burden following 131I therapy for thyroid cancer. Radiology 1980 137(3) 839 12. 

Blood lead levels provide the best indicators of lead poisoning but do not reflect total body burden (Lee and Moore 1990). The inhibition of erythrocyte 8-aminolevulinic acid indicates lead exposure, but most centers still use blood lead levels for screening (Lee and Moore 1990 Roper et al. 1993 Schaffer and Campbell 1994). Zinc protoporphyrin indicates neurotoxicity from lead but does not have the sensitivity for assessing low levels of exposure (Anger and Johnson 1985 Royce and Needleman 1995). Radiological examination of the abdomen and long bones does not reliably portray exposure. The same holds true for the examination of red blood cells for basophilic stippling and the assay of hair and nail levels for lead (Roper et al. 1993). The Centers for Disease Control and Prevention (CDC) does not recommend use of scarification of the forearm with 25% sodium sulfite solution to assess for black discoloration of skin, a procedure recommended in some sources. Medical centers perform an edetate disodium calcium provocative chelation test with urinalysis and complete blood... 

Biological Collection. Refer to USACHPPM s TG No. 211 for radiobioassay collection, labeling, and shipping requirements. If the patient urinates, the urine should be saved for analysis for radiological contamination. Normal urinalyses can be done on portions of the sample with safety, but the laboratory should be notified that there is a potential contamination with radioactive material. It is essential that the laboratory keep a record of the volumes of urine so those appropriate laboratories can make later calculations of estimated body burdens of radioactive materials. Fecal samples should also be taken and retained in addition to nose blows and swabs. 

In this book the term burden means the (1) financial costs, (2) administrative, research and other resource conunitments, and (3) radiological, social and other inqncts which sod must provide or endure in connection with disposal of radioactive wastes. Burden does not have the meaning formerly used in radiation protection terminology and thus is not limited to the quantity of radioactive substances carried within a human body or organ. 

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