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Nuclear Radiation – our friend or enemy? Its safety, its benefits at low levels and the wider use of nuclear science for public health and economic prosperity Wade Allison, Oxford University. Joan Pye Project, Newbury 27 March 2013. Marie Sklodowska-Curie 1867-1934 - PowerPoint PPT Presentation
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Nuclear Radiation – our friend or enemy?Its safety, its benefits at low levels
and the wider use of nuclear science for public health and economic prosperity
Wade Allison, Oxford University
Joan Pye Project, Newbury27 March 2013
27 March 2013 Joan Pye Project, Newbury 2
Marie Sklodowska-Curie 1867-1934Physicist, chemist, radiologist = “Nothing in life is to be feared. It is to be understood.”
Charles Darwin 1809-1882student of divinity, naturalist, biologist, geologist,
Florence Nightingale 1820-1910Nurse and pioneering statistician = “How very little can be done under the spirit of fear” Adam Smith 1723-1790Economist and philosopher = “Science is the great antidote to the poison of enthusiasm and superstition”
27 March 2013 Joan Pye Project, Newbury 3
From the safety frontline An unsolicited email (Dec 2012) from Ken Chaplin, a senior long-time inspector in the nuclear industry:
“First, concerns for radiation protection outweigh concerns for industrial safety. One example, four of us were working in a relatively high temperature environment in lead jackets and plastic lined suits. The radiological hazards were insignificant, but two of us almost passed out from the heat in a very difficult to access location. Then, I had staff climbing ladders attached to walls, with very little space to get their feet on the ladder rungs. They were required to wear steel toed shoes, inside rubber "one size fits all" boots, inside paper booties. The extra layers were in the name of contamination control; however, I am far more concerned about people falling 8 metres onto piping.
Second, staff are increasingly worried about low levels of contamination in spite of ever increasing efforts to eliminate contamination. In my opinion, this results in much lower productivity and higher stress levels caused, and experienced, by the entire organization pursuing ALARA, without accompanying health benefits.
I am watching as radiological protection dogma, in particular ALARA, stops the nuclear industry dead in its tracks. It is hard to prevent this, but I am trying.”
ALARA safety restrictions, intended to allay fears, achieve the opposite. Regulation and worker stress drive up costs, bring no benefit and are economically damaging.
27 March 2013 Joan Pye Project, Newbury 4
Increased fear,
increased regulations,
increased costs and prices,
economic damage STOP!
“Science is the great antidote to the poison of enthusiasm and superstition”
27 March 2013 Joan Pye Project, Newbury 5
Reassurance from the physical science of nuclei?
15 February 2013 Trinity College Dublin 7
Oct 2011. Fukushima1 from 3 kms. Talks with doctors, teachers and community leaders (Minamisoma and Iitate)
27 March 2013 Joan Pye Project, Newbury 8
Already within a few days....Position apparent within a few days... 26 Mar 2011
27 March 2013 Joan Pye Project, Newbury 9
Food RegulationJuly 2011. Less than 500 Bq/kg = 0.008 mSv per kg
One CT scan = 8 mSv = eating 8/0.008 = 1000 kg = 1 tonne in 3 months
PROTEST!!! April 2012. 100 Bq/kg, so CT scan = 5 tonnes in 3 months
WaterApril 2011. 11,500 tonnes release into sea, intentionally
a) 100 times regulation limit. b) “Quite safe”. Both statements true!!
2 CT scan equivalent to drinking a litre a day for 3 months.
EvacuationCould have been 60 times less stringent. Go home after 2 weeks
But PROTEST!!!
27 March 2013 Joan Pye Project, Newbury 10
Why are there no casualties at Fukushima?
27 March 2013 Joan Pye Project, Newbury 11
Evolved over 100s millions years Static design of life
many individuals, many cells each with complete DNA copy, double stranded DNA, steady cell renewal by cycle, steady individual renewal by birth-sex-death cycle
Dynamic reactionby antioxidants, by inter-cellular signalling, by apoptosis, by DNA repairs, by cell cycle suspension, by immune reaction
Gentle stimulated changeextra antioxidants, added repair enzymes, adaptive immune system
For all life, plants and animals, with/without brain
For all damage, from radiation and other oxidative sources
27 March 2013 Joan Pye Project, Newbury 12
“Omnia sunt venena, nihil est sine veneno, Solo dosis facit venenum” Paracelsus (1493-1541)
27 March 2013 Joan Pye Project, Newbury 13
27 March 2013 Joan Pye Project, Newbury 14
A plastic carrier bag giving simple accessible advice about personal responsibility for safety from ionising radiation (ultraviolet in sunshine). This advice engages with the enjoyment of life and common sense, not imposed safety regulations emanating from an international committee. Just the local pharmacy telling Mum and Dad -- what a breath of fresh air!
27 March 2013 Joan Pye Project, Newbury 15
How might Florence Nightingale have established trust in radiation?
27 March 2013 Joan Pye Project, Newbury 16
1. Evidence. Measure thresholds
Get factors of 10 right, ignore factors of 2Ignore iffy data with small samples or tiny doses
Chernobyl Fire Fighters Acute ARSHiroshima & Nagasaki Acute Cancer Dial Painters Chronic CancerRadiotherapy fractionation Protracted Secondary cancerAnimal experiments Chronic Cancer
2. Draw pictures of data for authorities
3. Connect by explaining benefits of high clinical doses and contrasting with the tiny Fukushima doses
4. Press for withdrawal of ALARA radiological standards with the damage they cause to social health, to the economy, to the environment, to normal industrial safety
27 March 2013 Joan Pye Project, Newbury slide 17
Crosses show the mortality (curve is for rats). The numbers show the number who died/total in each dose range.
Above 4,000 mSv 27/42 died from ARS in 2/3 weeks. Below 2,000 mSv zero out of 195 died.Acute threshold about 2000 mSv
Chernobyl early firefighters
A poster advertising the availability and benefit of scans using internal and external sources of radiation. The (quite harmless) radiation dose (10 mSv) from a single scan exceeds the dose received by eating 5 tonnes of food described as "contaminated" (100 Bq/kg caesium-137) by the Japanese regulations introduced in April 2012
27 March 2013 Joan Pye Project, Newbury 19
tumour fractions total dose interval
bladder 30 x 2000 mSv 60000 mSv 5 times a week
breast 16 x 2750 mSv 42500 mSv 5 times a week
arm pit 15 x 2700 mSv 40000 mSv 5 times a week
glioma 30 x 2000 mSv 60000 mSv 5 times a week
cervical 25 x 1800 mSv 45000 mSv 5 times a week
lung 36 x 1800 mSv 54000 mSv over 12 days
prostate 39 x 2000 mSv 78000 mSv 5 times a week
[Doses actually given in gray where 1000 mSv = 1 gray, for gammas.]
Radiotherapy doses (tumour) recommended by Royal College of Radiologists
27 March 2013 Joan Pye Project, Newbury 20
Getting the radiation through the body into the tumour (schematic)
27 March 2013 Joan Pye Project, Newbury 21
Radiotherapy dose contours of a prostate cancer treatment.Section of lower abdomen perpendicular to the spine. Rectum shown shaded.
Contours at 97, 90, 70, 50, 30% of peak dose
[From an image by kind permission of Medical Physics and Clinical Engineering, Oxford Radcliffe NHS Trust.]
27 March 2013 Joan Pye Project, Newbury slide 22
Statistics, graphics and public persuasion Florence Nightingale
27 March 2013 Joan Pye Project, Newbury slide 23
Monthly doses depicted as areas
Tumour doseFATAL
40,000 mSv a month
Tolerated dose 20,000 mSv a month
A conservative safe dose (AHARS). Less than Dial Painter threshold.100 mSv per month. [Also max 5000 mSv per lifetime, for the present]
Current public “safe” dose (ALARA). Small addition to natural Background0.1 mSv per month, [or 1 mSv per yr]
As High As Relatively Safe (AHARS)would be a relaxation by about 1000 times overAs Low As Reasonably Achievable (ALARA) .
27 March 2013 Joan Pye Project, Newbury 24
Stories from Africa (Oklo Reactor) and South America (Goiania Accident)
In Gabon, Oklo 2,000 million BChttp://en.wikipedia.org/wiki/Natural_nuclear_fission_reactor
Then U was naturally enriched, 3% U-235water moderated reactors ran for a million years, no regulation, no decommissioning -- waste still in situ
In Brazil, Goiania, 1987 – story of bad record keeping
50.9 TBq Cs-137 medical source, lost. [Why so intense?]Children played with “blue light” from 13-29 Sept!28 serious skin burns 129 internal contam, (105 @ 0.1-0.5Gy, 24 @ 0.5-7.0Gy)8 Acute Radiation Syndrome, 4 deaths by 27 Octall blood counts normal after 1988after 10 yrs, one malignant skin cancer (treated)
27 March 2013 Joan Pye Project, Newbury slide 25
Conclusions1. At worst Radiation is a modest local danger, not a global threat like: climate change, political & economic instability, population,water and food
2. Could relax safety levels by ~1000 times, As High As Relatively Safe (AHARS), no extra risk, major cost reduction 100mSv single acute dose, and 100mSv/month chronic/protracted dose rate, and 5000mSv whole-of-life, say.3. Education, to remove stigma of nuclear, to spread trust in science and trust in society and to explain radiation in simple terms 4. As with personal health, to use nuclear radiation for the benefit of all, especially nuclear power for health of planetBooks and downloads www.radiationandreason.com Books on sale today at £12
27 March 2013 Joan Pye Project, Newbury 26
?Fear of radiationWhy?
1. Fear of the aftermath of a nuclear holocaust. An effective Cold War message that frightened everybody at the time.
2. Cannot feel nuclear radiation. - OK, get a detector, a smoke detector - Even better, the cells of your body can feel - repair the damage, too.
3. The international regulations (ICRP) designed to keep lid on public opinion by promising no more than background levels, 1 mSv per year. As Low As Reasonably Achievable (ALARA)
27 March 2013 Joan Pye Project, Newbury slide 27
Is local dose or wholebody dose the important measure?
1. The initial energy loss is local (LET)2. The early cell damage is local except for some spread by ROS migration/ the Bystander Effect3. It is granted that the same local dose when applied over a larger volume
should have an incidence of disease proportional to that volume.4. In Radiotherapy it is the local radiation dose that kills the cells, not the wholebody dose, otherwise directing the dose would be pointless5. Secondary cancers occur in the irradiated region.6. Sites of initial carcinogenesis are relatively local to the causative radiation site: eg skin cancers are on the exposed skin, smoking gives mainly lung cancer, excess drinking gives mainly liver cancer not lung or skin
cancers, etc Most precisely, radio-iodine is trapped by the thyroidand causes thyroid cancer, not another cancer.)
7. Only when the cancer metastasises does it migrate elsewhere8. The idea that wholebody dose is the appropriate measure comes from
the LNTH which would validate dose averaging, as it would for a whole population (as in use of man-sievert).
27 March 2013 Joan Pye Project, Newbury slide 28
20 Feb 2013
NUCLEAR POLICIES: Chaos in Bulgarian energyAn energy crisis has triggered mass demonstrations, the resignation of the Bulgarian government and cyber attacks on electricity distributor CEZ. A long-running failure to maintain generating capacity underlies the country's problems.
NUCLEAR POLICIES: Trillion-euro cost of German energy transitionGermany's plan to transform its energy system to one reliant on renewable power as it phases out nuclear energy could cost up to €1 trillion, German energy and environment minister Peter Altmaier has publicly admitted.
Figure 8. Canisters, each volume representing the mass of waste per person per day (UK).
On the left 30 kg CO2 from fossil fuels. Direct atmospheric discharge. Fire is thermal chain reaction,