The 39th Ockham Lecture - ‘Levels and Effects of Radiation Exposure’

Date: Thursday 23 May 2024
Time: 17:00 - 19:00
TS Eliot Theatre, Merton College

To be given by Malcolm Crick Merton College (1977), Director of the Secretariat (2005-17), United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), Vienna Head (1996-2005), Incident & Emergency Centre, International Atomic Energy Authority


A recent Netflix series reminded us of the tragedy of Chernobyl. On 26 April 1986, in the then Ukrainian Soviet Socialist Republic, the Chernobyl Nuclear Power Plant suffered what was to be the world's worst reactor accident. At the time there was much fear across the world about its consequences. The public were poorly equipped to understand the main issues and to gain perspective. The media also struggled. Arnold Allen in the Financial Times of September that year wrote: "All I know about the becquerel is that, like the Italian lira, you need an awful lot to amount to very much". It is fair to say that poor communication led to a lack of trust in authorities, which subsequently drove poor decisions and delayed recovery. Nowadays, the public remain blissfully unaware of the radiation environment in which we all live, and yet would expect any scientist to be able to answer their questions, should the need arise. In this lecture I will share insight on radiation risk communication gleaned from a professional career of more than 35 years at the national and international level. I will draw on experience whilst heading the IAEA's Incident and Emergency Centre, and as Director of the Secretariat for UNSCEAR. I will recall the quantities and units used to express human exposure to ionising radiation and give an overview of the levels of exposure across the globe. You should be able to appreciate the relative contributions made by the various natural and artificial sources of radiation to human exposure, be they related to members of the public, specifically medical patients, or to workers. I will also summarise present knowledge about the human health risks and effects of radiation exposure and share current understanding of the mechanisms involved. Along the way, I will take you behind the scenes and share how international agencies have addressed challenges raised by, inter alia, atmospheric nuclear weapons testing, and the Chernobyl and Fukushima accidents, and how they have responded to new findings on the risks of exposure such as to radon gas and the increasing usage of CT scans in medicine.

The Ockham Lecture Series

The Merton College Physics Lecture (the Ockham, or Occam, Lecture, so named in honour of one of the greatest—if unattested—alumni of the College and of his philosophical principle of intellectual discipline) started in 2009 and is held once a term. It is organised by the physics tutors of the College to promote both intellectual curiosity and social cohesion of the Merton Physics community.

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