title: Samarium-153 EDTMP for metastatic bone pain palliation: the impact of europium impurities.
abstract: OBJECTIVE
  To evaluate the impact on the radiation protection policies of the radiocontaminants in Samarium-153 ethylenediamine tetramethylene phosphonate ((153)Sm-EDTMP).
  
  
  METHODS
  The internal contamination of patients treated with (153)Sm-EDMTP for palliation of painful disseminated multiple bone metastases due to long-lived impurities was assessed by direct measurements. These measurements were coupled with dose-rate measurements close to their bodies and spectroscopic analysis of the residual activity in post-treatment radiopharmaceutical vials.
  
  
  RESULTS
  Whole-body counting carried out in six patients showed a 30-81-kBq europium -152 plus europium-154 contamination. The 0.85 mean (152)Eu- to -(154)Eu activity ratio obtained by direct counting was similar to that assessed by analysis of post-treatment residual activities in twelve radiopharmaceutical vials following radiopharmaceutical injection.
  
  
  CONCLUSIONS
  The long-lived radiocontaminants in the patient's bodies and the treatment wastes require modifications of the applicable radiation protection policies.
authors.affiliation: Medical Physics Department, University of Ioannina, Ioannina 451.10, Greece. Electronic address: jkalef@cc.uoi.gr.
authors.forename: J A
authors.initials: JA
authors.lastname: Kalef-Ezra
authors.affiliation: Medical Physics Department, University of Ioannina, Ioannina 451.10, Greece.
authors.forename: S T
authors.initials: ST
authors.lastname: Valakis
authors.affiliation: Medical Physics Department, University of Ioannina, Ioannina 451.10, Greece.
authors.forename: S
authors.initials: S
authors.lastname: Pallada
mesh_terms: D001859:Bone Neoplasms / Q000150:complications*; D005063:Europium / Q000737:chemistry*; D005720:Gamma Rays; D006801:Humans; D009942:Organometallic Compounds / Q000737:chemistry* / Q000627:therapeutic use*; D009943:Organophosphorus Compounds / Q000737:chemistry* / Q000627:therapeutic use*; D059408:Pain Management; D010166:Palliative Care; D011829:Radiation Dosage; D011835:Radiation Protection; D011854:Radiochemistry; D011868:Radioisotopes / Q000737:chemistry*; D019275:Radiopharmaceuticals / Q000737:chemistry; D014915:Whole-Body Counting
chemical_list: D009942:Organometallic Compounds; D009943:Organophosphorus Compounds; D011868:Radioisotopes; D019275:Radiopharmaceuticals; D005063:Europium; C061972:samarium Sm-153 lexidronam
keywords: Radiation protection; Radionuclide purity; Radiopharmaceuticals; Whole-body counting