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In the opening editorial to the June 2011 issue of the Journal of Radiological Protection (see http://iopscience.iop.org/0952-4746/31/2/E02/pdf/0952-4746_31_2_E02.pdf) SRP Member and Journal Editor, Prof Richard Wakeford of the Dalton Nuclear Institute, The University of Manchester, gives a detailed account of events at Fukushima Dai-ichi Nuclear Power Station, and poses several questions that remain unanswered, several weeks on from the earthquake and tsunami on 11 March.  Taking a close look at information disclosed by Japanese government ministries, the World Health Organisation, the International Atomic Energy Agency and others, Professor Wakeford details events at the six different reactors, and the consequent releases of radioactivity.

While praising the organisational abilities of the Japanese authorities and the heroic efforts of emergency workers, Prof Wakeford is critical of alarmist pronouncements from some of those in authority outside Japan, and offers perspective on the radiological hazard the emergency poses.  He highlights a peculiarity of the International Nuclear and Radiological Event Scale (INES).  The INES, designed to communicate to the public the severity of events at nuclear facilities, rather confusingly brackets Fukushima with Chernobyl as a Level 7 major accident, despite Fukushima only having released 10% of the radioactivity released by Chernobyl at the time the INES announcement was made.  Professor Wakeford explains, "Since Level 7 is the highest rating on INES there can be no distinction between the Fukushima and Chernobyl accidents, leading many to proclaim the Fukushima accident as 'another Chernobyl', which it is not....... A situation which has led to criticism of the INES."

Prof Wakeford also highlights how lessons have been learnt since Chernobyl and have helped guide the actions taken by Japanese authorities, including the establishment of a 20km radius evacuation zone, banning the consumption of contaminated foodstuffs, issuing stable iodine tablets, and the monitoring of the thyroids of nearly 1,000 children in badly affected areas.  He also compares the reality on the ground – sad but orderly evacuations and low level radiation risks among the most vulnerable – with the pronouncements from some of those in authority outside Japan which, Wakeford writes, "have been breathtaking in their extravagance." 

While the monitoring of radiation levels across and beyond Fukushima Prefecture, and among those most likely to be affected, has returned results more encouraging than much of the speculation would suggest, Wakeford does point to some serious ongoing concerns.  One difficult decision facing the Japanese authorities is when and if evacuees are allowed to return to their homes.  This will be especially problematical in the sector to the north-west of the site that has been particularly badly affected, and measures are likely to be needed in certain areas to reduce radiation levels before people are permitted to live there permanently.  Another key concern is how authorities will contain and deal with the highly contaminated water that has been found to be present on the Fukushima site.Many questions surrounding events in Fukushima remain unanswered, most hinging on whether emergency systems were adequate to meet foreseeable, even if unlikely, circumstances.

Professor Wakeford concludes, however, in admiration of Japanese courage, "Given the difficult background circumstances pertaining in Fukushima Prefecture as problems mounted at the Fukushima Dai-ichi NPS, the organisational abilities of the Japanese authorities in dealing with the evacuation, monitoring and protection of the public has to be admired.  In particular, the heroic efforts of the emergency workers, battling under conditions that were often atrocious, should not pass without respect and praise."

18th May 2011

Map showing Comparison of Contamination around Chernobyl with that around Fukishima (PDF) 

 Source: UNSCEAR (for Chernobyl) and the Japanese Ministry of Education, Culture, Sports, Science and Technology ("MEXT", for Fukushima) 

The IRSN has produced an animation of the travel of the plume from Chernobyl at: http://www.irsn.fr/EN/Library/in-depth/Pages/indepth_The-Chernobyl-Plume.aspx

Other free-to-read articles on the JRP website (http://iopscience.iop.org/0952-4746) of interest to the accident at Fukishima:

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It seems clear that around 15 March a plume of radioactive material travelled to the north-west of the Fukushima site and that certain communities in this direction (including some beyond the 20 km evacuation zone) received significant fallout as a consequence, presumably enhanced by rainfall in the worst affected areas. The Japanese authorities needed to take action, initially to ensure that foodstuffs contaminated to an unacceptable level were not consumed (especially when radioactive iodine could get to the thyroid glands of young children). In the short-term, short-lived radionuclides decayed so the dose-rate from deposited radioactive material fell quite notably, but in some communities (e.g. Iitate) this has levelled out at around 5 microsievert per hour (presumably mainly due to Cs isotopes), which is at a level that the Japanese authorities considered necessary to evacuate people from these communities, which is what they are doing.

It is fortunate that the north-west sector is the only area to be significantly affected in this way, most of the releases going out to sea. The Japanese authorities do seem to have acted appropriately to limit doses received by people; but some communities in this north-west sector may be evacuated for a time and remediation measures may be necessary to reduce dose-rates. Other communities, including those within the 20 km evacuation zone, should not be such a problem, although it is unlikely that the authorities will permit people to return to the evacuation zone until the situation at the Fukushima site is fully under control.

SRP, 14th April 2011

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Headlines in some national newspapers are highlighting that levels of fallout from the Fukushima Reactor incident are now being detected in the UK. This is following results reported by the HPA which show that airborne levels are minuscule. In fact being able to measure anything at all is credit to the sensitivity of the radiological monitor equipment being deployed and should provide reassurance to people that there are no issues of concern. The HPA statement can be found at www.hpa.org.uk/NewsCentre/NationalPressReleases/2011PressReleases/110329StatementonFukushima/

The SRP wishes to express its sympathy and support to all those affected by the tsunami and the consequent damage to the Fukushima nuclear power station, and solidarity with our Japanese colleagues involved in dealing with containment of the spread of radioactive contamination and its consequences.

SRP, 30th March 2011

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The Japanese earthquake and subsequent tsunami have had a serious impact on several Japanese nuclear reactors, principally those at the Fukushima Daiichi site.

The Society for Radiological Protection can only offer advice remotely – we have no special links to information but we are concerned about potential radiation exposures associated with these reactor problems.

We believe that the automatic shut down of reactors and the time from shutdown to the further problems associated with loss of cooling systems will mitigate the magnitude of the problems. We wish to do what we can to advise our members and the public on these events associated with the Japanese nuclear plants.

For the time being, we suggest the following sites provide generally reliable and trustworthy information. We will respond to further reports about potential radiation exposures when we have more information ourselves.

For useful background information:

• SRP (www.srp-uk.org/resources/faqs)
• Nuclear Regulatory Commission (www.nrc.gov/)
• International Radiation Protection Association (www.irpa.net/)

For updates from the international community:

• International Atomic Energy Agency (www.iaea.org/newscenter/news/tsunamiupdate01.html)
• World Health Organization (www.who.int/hac/en/index.html)
• Statement from Bernard Bonin, Chairman of the ENS High Scientific Council as at 18th March.

For updates from the Tokyo Electric Power Company:

          www.tepco.co.jp/en/press/corp-com/release/index-e.html

For information from the HPA:

         www.hpa.org.uk/NewsCentre/NationalPressReleases/2011PressReleases/110317StatementaboutFukushima/

For UK government travel advice for Japan:

• Foreign and Commonwealth Office (www.fco.gov.uk/en/news/latest-news/?view=News&id=564856182)

SRP Member and Journal editor Richard Wakeford has carried out a number of media interviews on behalf of the SRP in which he was able to put into perspective some of the concerns currently being raised by the media.   He has highlighted that the Japanese authorities are doing the right things to minimise thyroid doses amongst children which was not done at Chernobyl, which is why the number of thyroid cancers was so high from this accident.  Richard has been liaising with the Science Media Centre in London regarding press briefings with a number of others which hopefully will be helpful in providing the media with a balanced view. Rick Hallard (Past President) has also volunteered to field any media questions on behalf of the SRP and his details have been provided to media organisations.

We are grateful to SRP member Ludovic Chevallereau who has passed on  information he has received through The French Nuclear Society: click here for pdf :: Fukushima Summary

This is an ever changing situation so members can keep themselves updated through information from the International Atomic Energy Agency website (address above) . Reactor No.4 currently has no fuel present since it was defueled late November 2010, Reactor No.5 has fuel but was shut down early in January 2011 and reactor No.6 has fuel but was shut down mid August 2010.