• 21st L H Gray Conference: the radiobiology/radiation protection interface.

      West, Catharine M L; Martin, C J; Sutton, D G; Wright, Eric G; Academic Department of Radiation Oncology, University of Manchester, Christie Hospital, UK. catharine.west@manchester.ac.uk (2009-05)
      The 21st L H Gray Conference, organised by the L H Gray Trust with the Society for Radiological Protection, brought together international experts in radiobiology, epidemiology and risk assessment, and scientists involved in diagnostic and therapeutic radiation exposure. The meeting - held in Edinburgh, Scotland, on 4-6 June 2008 - aimed to raise awareness, educate and share knowledge of important issues in radiation protection. A distinguished group of speakers discussed topics that included (i) non-targeted effects of radiation, (ii) exposure to high natural background radiation, (iii) non-cancer effects in Japanese bomb survivors, (iv) lessons learnt from Chernobyl, (v) radiation in the workplace, (vi) biokinetic modelling, (vii) uncertainties in risk estimation, (viii) issues in diagnostic medical exposures, (ix) lessons leant from the polonium-210 incidence and (x) how the radiobiology/radiation oncology community is needed to help society prepare for potential future acts of radiation terrorism. The conference highlighted the importance, relevance and topicality of radiobiology today.
    • The radiobiology/radiation protection interface in healthcare.

      Martin, C J; Sutton, D G; West, Catharine M L; Wright, Eric G; Department of Clinical Physics and Bio-engineering, Gartnavel Royal Hospital, Glasgow, UK. (2009-06)
      The current knowledge of radiation effects is reviewed and implications for its application in healthcare considered. The 21st L H Gray conference gathered leading experts in radiobiology, radiation epidemiology, radiation effect modelling, and the application of radiation in medicine to provide an overview of the subject. The latest radiobiology research in non-targeted effects such as genomic instability and the bystander effect challenge the old models, but the implications for health effects on humans are uncertain. Adaptive responses to external stresses, of which radiation is one, have been demonstrated in cells and animal models, but it is not known how these might modify human dose-effect relationships. Epidemiological evidence from the Japanese A-bomb survivors provides strong evidence that there is a linear relationship between the excess risk of cancer and organ dose that extends from about 50 mSv up to 2.5 Sv, and results from pooled data for multiple epidemiological studies indicate that risks extend down to doses of 20 mSv. Thus linear extrapolation of the A-bomb dose-effect data provides an appropriate basis for radiological protection standards at the present time. Risks from higher dose diagnostic procedures fall within the range in which health effects can be demonstrated. There is therefore reason for concern about the rise in the number of computed tomography (CT) scans performed in many countries, and in particular the use of CT for screening of asymptomatic individuals. New radiotherapy techniques allow high dose radiation fields to be conformed more effectively to target volumes, and reduce doses to critical organs, but they tend to give a higher and more uniform dose to the whole body which may increase the risk of second cancer. It is important that radiation protection practitioners keep abreast of developments in understanding of radiation effects and advise the medical community about the implications of fundamental research when planning medical applications for the future.