Professor Wade Allison, Emeritus Fellow, Keble College, Oxford, UK Science Cafe at the Tobacco Factory, Bristol. Presentation on 27 June 2011.

1. Life and nuclear radiation Chernobyl and Fukushima in perspective Wade Allison Oxford University ..... to remove a barrier in the mind, a relic of the Cold War

2. 2,000 million yrs ago modern times Earth hot with carbon dioxide (like Venus today) cool with oxygen Storing sunlight energy carbon dioxide photosynthesis sun light plantlife oxygen fossil fuel Discharging stored sunlight energy Plantossil fuel carbon dioxide fire oxygen released energy

3. Fire is dangerous - but we got the wrong danger!

4. CO2 in the atmosphere is rising v. fast accelerated timescale 200X 8000X

6. ? Only problem? Fear of radiation! Why?

7. Influences of nuclear technology . What is the effect of radiation on life? Both data and understanding. First Second And finally Risk assessment. Public acceptance. Safety regulations. Working practices. Waste. Costs. Terrorists, Rogue states. Dirty bomb threats. Nuclear blackmail

8. Two different questions - As Low As Reasonably Achievable ALARA - As High as Relatively Safe AHARS 1000 X Explanation in SIMPLE language and a few important details Ionising Radiation safety single slide summary

10. Mortality of Chernobyl firefighters above 4,000 mSv 27/42 died in a few weeks Acute Radiation Syndrome below 4,000 mSv 1/195 died. (the curve is for laboratory rats, shifted a little)

11. Radiotherapy doses (tumour) recommended by Royal College of Radiologists [Doses actually given in gray where 1000 mSv = 1 gray, for gammas.]

12. Dose contours for prostate radiotherapy plan (section) 97% 90% 70% 50% (heavy) 30% Healthy tissue receives 50% dose relative to tumour [From an image by kind permission of Medical Physics and Engineering, Oxford Radcliffe Hospitals NHS Trust]

13. a) no feedback/repair = linearity b) stabilising feedback, up to a limit = non-linearity like a bridge in the wind...

14. Hiroshima & Nagasaki Early death Lost Cancer death 1950-2000 Radiation induced cancer 1950-2000 Survived to 1950 and did not die of cancer before 2000

15. Solid cancer deaths of survivors with measured doses

16. Leukaemia deaths of survivors with measured doses

17. Graphics, public persuasion and Florence Nightingale

18. A safe monthly radiation dose? By area Tumour therapy > 40,000 mSv per month Healthy tissue therapy > 20,000 mSv per month Suggested safe level 100 mSv per month, [conservative by a factor 200] Sellafield waste storage hall 24/7, 1 mSv per month, [or 1 micro Sv per hr] International public “safe” level 0.1 mSv per month, [or 1 mSv per yr] 100 mSv max single dose 100 mSv max in any month 5000 mSv max lifelong So change for public by factor 1000, As High As Relatively Safe (AHARS), instead of As Low As Reasonably Achievable (ALARA) Suggested new safety levels:

19. Graphics on risk in the making!

21. Fukushima, the decay heat ....it continues to getting ever smaller.... the radioactivity of spent fuel

22. http://www.msm.cam.ac.uk/teaching/partIII/courseM17/Lecture_9.pdf

23. 100 mSv per month = 138 microsievert per hour

25. [Abstract of the article] [signed]

27. So -- welcome and respect radiation cures many 1000s of cancers every year; educate, tell people about radiation in simple words, radiation is not unimaginably dangerous; regulate for actual danger, not fear based on unquantified aversion, affecting solutions to waste and decommissioning; new nuclear power for the sake of the environment electricity, desalination, food irradiation; geological, sociological, reactor stability. Read book and http://www.radiationandreason.com Hope for 21st century problems, ONLY IF we re-assess 20th century worries. Requires trust, thought, education and reform.

28. Japan's nuclear evacuees shunned over health fears KITAKAMI, Japan (AFP) – People fleeing Japan's crippled nuclear plant are being turned away from evacuation centres because of unfounded fears they might contaminate others with radiation. Those made homeless by the emergency at the stricken Fukushima Daiichi atomic plant need local government-issued certificates proving they are not contaminated before they are allowed to step foot inside the centres. Screening facilities set up to soothe concerns over radiation have become checkpoints that determine access to a place to sleep and -- in at least one case -- healthcare, even though experts say evacuees pose no risk to others.. "Unless they are plant workers, ordinary people aren't dangerous," said Kosuke Yamagishi of Fukushima prefecture's medical services division. "People are simply over-reacting, and sadly this could lead to discrimination," he told AFP. An eight-year-old girl from Minamisoma was refused treatment for a skin condition in a hospital in Fukushima city because she did not have a screening certificate, the Mainichi daily reported. The girl's father, Takayuki Okamura told the paper: "I am worried already with my life as an evacuee. It was a real shock to have the appointment refused." But those running evacuation centres are unapologetic.