Glovebox-processing techniques for C1 quantities of reactor-produced beta emitters

Our group has extensive experience producing beta emitting radioisotopes, including curie quantities of Re-186, Sm-153, Ho-166 and Lu-177. Using finger and wrist dosimeters dedicated for single-isotope use, we have evaluated the effectiveness of new techniques and shielding implemented over the past 16 years. Simple 1/2'' acrylic shields made by our machine shop attached to pipets and forceps have essentially eliminated measurable beta exposure, even from 8 glovebox processing. Changes in target form and processing techniques have reduced the average extremity exposure for glovebox-processing. This experience from our processing laboratory has implications for technologists who may handle these and other beta emitting nuclides in their clinics. Isotopically enriched targets (72-100%) minimize radioisotopic impurities, but some impurities originate from alternate activation reactions of the primary target isotope (Ho-166m, Lu-177m) or 8 from activation of daughter isotopes as the desired species decays during irradiation (Sm-153 (beta) Eu-153 (n,gamma) Eu-154). These unavoidable radioactive impurities inherent in (n,gamma) production can affect the measurement, disposal, and patient dosimetry of the beta emitting radionuclides. We have analyzed and quantified the significant impurities co-produced with the isotopes of interest (Re-188 in Re-186, Ho-166m in Ho-166, Lu-177m in Lu-177, and Eu-154, Eu-155 and Eu-156 in Sm-153), and have explored the implications of these observations. (authors)