Protection of Human Health and the Environment by Means of Predisposal Management of Medical Solid Radioactive Waste

摘要

Aim: A radioactive waste management programme is a well-established practice in clinical departments that utilize radioactivity for both diagnostic and therapeutic purposes. Such a programme must ensure the effective organization of all activities relating to radioactive waste management, the presence of internal procedures and the maintenance of records, in order to assure full compliance with radiation protection and safety requirements. A study was carried out to determine whether certain quantitative parameters describing medical radioactive waste are correlated with the level of training and experience of the operating personnel. Materials and methods: Data collected concerned medical radioactive waste generated during the first 48 months of operation of the Department of Nuclear Medicine, University General Hospital of Athens "Attikon". It was examined whether a correlation exists between released (Ar, in Bq) and utilized activity (Au, in mCi), between released waste mass (mr, in gr) and A,,, as well as between the ratio (Ar/Au, in Bq/mCi) and time (t, in months). All parameters were calculated separately for shortlived (e.g. Tc-99m) and long-lived (e.g. TI-201, Ga-67) y-emitting isotopes. Results: The existence of correlation was examined by means of ANOVA. With respect to (A,.) vs (Au), it was showed that there is a statistically significant increase of Ar with A,, for short-lived isotopes, whereas no correlation exists for long-lived isotopes. As far as (mr) vs (A,,) is concerned, no correlation exists for both types of isotopes. Finally, no trend was observed in (Ar/Au) vs (t) for short-lived isotopes, while for long-lived isotopes the relationship is that of a statistically significant decrease. Discussion: Good operating practice reduced significantly the value of Ar/A,, for long-lived isotopes. Additionally, there was no increase of mr with time for both types of isotopes. In this way, both environmental risk and financial burden for our hospital were reduced.