Estimation of the collective ionizing dose in the Portuguese population for the years 2011 and 2012, due to nuclear medicine exams / Estimación de la dosis colectiva en la población portuguesa de los años 2011 y 2012, debido a los exámenes de medicina nuclear

Objectives. In 2009-2010 a Portuguese consortium was created to implement the methodologies proposed by the Dose Datamed II (DDM2) project, aiming to collect data from diagnostic X-ray and nuclear medicine (NM) procedures, in order to determine the most frequently prescribed exams and the associated ionizing radiation doses for the Portuguese population. The current study is the continuation of this work, although it focuses only on NM exams for the years 2011 and 2012. Material and methods. The annual frequency of each of the 28 selected NM exams and the average administered activity per procedure was obtained by means of a nationwide survey sent to the 35 NM centres in Portugal. Results. The results show a reduction of the number of cardiac exams performed in the last two years compared with 2010, leading to a reduction of the annual average effective dose of Portuguese population due to NM exams from 0.08 mSv ± 0.017 mSv/caput to 0.059 ± 0.011 mSv/caput in 2011 and 0.054 ± 0.011 mSv/caput in 2012. Portuguese total annual average collective effective dose due to medical procedures was estimated to be 625.6 ± 110.9 manSv in 2011 and 565.1 ± 117.3 manSv in 2012, a reduction in comparison with 2010 (840.3 ± 183.8 manSv). Conclusions. The most frequent exams and the ones that contributed the most for total population dose were the cardiac and bone exams, although a decrease observed in 2011 and in 2012 was verified. The authors intend to perform this study periodically to identify trends in the annual Portuguese average effective dose and to help to raise awareness about the potential dose optimization (AU)

Objetivo. En 2009 y 2010 un consorcio portugués ha sido creado para implementar las metodologías propuestas por el proyecto europeo Datamed II (DDM2), con el objetivo de coleccionar datos de procedimientos de radiología de diagnóstico y medicina nuclear (MN) más frecuentes, así como la dosis asociada en la población portuguesa. Este estudio es una continuación del trabajo, que se centrará en los datos de MN para los años de 2011 y 2012. Material y Métodos. La frecuencia anual de cada uno de los 28 exámenes de MN seleccionados y la actividad media administrada por procedimiento se obtuvieron a través de una encuesta enviada a los 35 departamentos de MN en Portugal. Resultados. Los resultados muestran una reducción drástica en el número de procedimientos cardiacos en los últimos dos años, lo que tiene como consecuencia una reducción de la dosis efectiva anual en la población portuguesa derivado de procedimientos de MN de 0,08mSv±0,017 mSv/caput en 2010, a 0,059±0,011 mSv/caput in 2011 y 0,054±0,011 mSv/caput in 2012. La dosis efectiva colectiva media en la población portuguesa es estimada en 625.6 ± 110.9 manSv en 2011, y 565.1 ± 117.3 manSv en 2012. Conclusiones. Los exámenes cardiacos y óseos fueron más frecuentes y los que más contribuyeron para la dosis total de la población, aunque se verificó una disminución en 2011 y en 2012. Los autores de este trabajo pretenden realizar este tipo de estudios periódicamente para identificar tendencias en los diferentes procedimientos de MN y ayudar a aumentar la conciencia de los profesionales de MN sobre este asunto (AU)

Estimation of the collective ionizing dose in the Portuguese population for the years 2011 and 2012, due to nuclear medicine exams.

OBJECTIVES: In 2009-2010 a Portuguese consortium was created to implement the methodologies proposed by the Dose Datamed II (DDM2) project, aiming to collect data from diagnostic X-ray and nuclear medicine (NM) procedures, in order to determine the most frequently prescribed exams and the associated ionizing radiation doses for the Portuguese population. The current study is the continuation of this work, although it focuses only on NM exams for the years 2011 and 2012. MATERIAL AND METHODS: The annual frequency of each of the 28 selected NM exams and the average administered activity per procedure was obtained by means of a nationwide survey sent to the 35 NM centres in Portugal. RESULTS: The results show a reduction of the number of cardiac exams performed in the last two years compared with 2010, leading to a reduction of the annual average effective dose of Portuguese population due to NM exams from 0.08 mSv ± 0.017 mSv/caput to 0.059 ± 0.011 mSv/caput in 2011 and 0.054 ± 0.011 mSv/caput in 2012. Portuguese total annual average collective effective dose due to medical procedures was estimated to be 625.6 ± 110.9 manSv in 2011 and 565.1 ± 117.3 manSv in 2012, a reduction in comparison with 2010 (840.3 ± 183.8 manSv). CONCLUSIONS: The most frequent exams and the ones that contributed the most for total population dose were the cardiac and bone exams, although a decrease observed in 2011 and in 2012 was verified. The authors intend to perform this study periodically to identify trends in the annual Portuguese average effective dose and to help to raise awareness about the potential dose optimization.

Study of nuclear medicine practices in Portugal from an internal dosimetry perspective.

Nuclear medicine practices involve the handling of a wide range of pharmaceuticals labelled with different radionuclides, for diagnostic and therapeutic purposes. This work intends to evaluate the potential risks of internal contamination of nuclear medicine staff in several Portuguese nuclear medicine services and to conclude about the requirement of a routine internal monitoring. A methodology proposed by the International Atomic Energy Agency (IAEA), providing a set of criteria to determine the need, or not, for an internal monitoring programme, was applied. The evaluation of the risk of internal contaminations in a given set of working conditions is based on the type and amount of radionuclides being handled, as well as the safety conditions with which they are manipulated. The application of the IAEA criteria showed that 73.1% of all the workers included in this study should be integrated in a routine monitoring programme for internal contaminations; more specifically, 100% of workers performing radioimmunoassay techniques should be monitored. This study suggests that a routine monitoring programme for internal exposures should be implemented in Portugal for most nuclear medicine workers.

VUV spectroscopy of water under cellular conditions.

The understanding of radiation damage within cells, and thence mutagenesis, depends upon a detailed knowledge of the spectroscopy and dissociation dynamics of water. Results of a new study of the electronic state spectroscopy of water, using synchrotron radiation are reported. In order to gain some insight into how the spectroscopy and dissociation dynamics of water is influenced by its environment we also report photo-absorption spectra of water within thin films of poly(o-methoxyaniline) which have been suggested as a good mimic for biological membranes in the cellular environment. Comparison of these spectra with those of gaseous water and condensed amorphous water ice suggest that water in such films is similar to gaseous water and does not show the blue shift suggested in some cellular models. The lowest energy of OH production from dissociation of water in the cellular environment may therefore be around 6.7 eV (185 nm).