Analysis of Radiation Dose Effects and Emergency Response from Nuclear Power Accidents Thursday, May 17th 2012 American Nuclear Society, Northeastern Section Richard Wilson Mallinckrodt Professor of Physics (Emeritus) Harvard University

Responses to Fukushima : NRC correctly has two papers on making reactors safer, ANS is stressing these BUT nuclear power is dead for 50 years UNLESS ANS explains to the public that radiation is not the disaster they think (I continually challenge APS also) DO NOT BE LAZY understand and speak out

Topical issue – Fukushima a year ago- Evacuate or not? What do we know from previous incidents? Those who do not understand history are condemned to repeat it Medical X rays Radium Dial painters Hiroshima-Nagasaki Windscale (UK) TMI Chernobyl Tokai (Japan)

Avoid Acute Radiation Sickness (ARS) ARS can occur if dose in a week is > 200 Rems (2 Sv). But chronic doses can accumulate over years Chronic effects: cancer heart disease genetic effects No cancers specific to radiation Radiation can cause an increase in natural cancer rate Perhaps 30% at 200 Rems (maybe much less)

Suggested immediate actions Prior experience suggests: Avoid effects of iodine (don’t drink local milk (even mother’s milk) for a month Evacuate if needed to Avoid Acute Radiation Sickness If no Acute Radiation Sickness a day or two delay in considering evacuation makes little difference Let workers get higher doses than normal subject to acute radiation sickness

My Estimate of Dose at Site Boundary

My Dose at Site Boundary March 2012 calculation – Peak probably noble gases (little effect) followed by cesium. (134 and 137) – Take peak and multiply by width – Dose about 2 Rems (0.02 Sv) and falling – My CAT scan doses last year 2.4 Rems

Evaporation Temperature 184°C 671°C 1750°C 990°C

Products of Fission Gases (1) Noble Gases (Kryton,xenon) (2) Iodine goes to thyroid: leukemia, thyroid cancers (Do not drink milk for a month) Solids sublimate as temperature goes up (A) Cesium 134, 137. do not stay (B) Strontium, transuranics Only at higher temperature, not much even at Chernobyl Table not broken down by age (MY MISTAKE!)

What about Ibaraki? (on way to Tokyo)

It looks different with different scale. Dose Negligible

Adverse Effects of Evacuation – Stress can increase cancer rates 5% or more – Direct loss of life due to lack of facilities – NO ONE CONSIDERED THESE AT ALL

Subsequent study (IAEA, INPO, TEPCO, etc) confirms: No one got Acute Radiation Exposure (highest exposure in a worker 30 Rems) If there are cancers the probability of causation (POC) will be less than 50% in all but a few cases.

These are the locations of measurement

BEIR report on effects of radiation Not broken down by age

Deposition to NW of plant highest from Tuesday/Wednesday releases

Rems/man or manRems? Traditionally health physicists assume a linear dose response and then it is clear that the societal effect is best expressed in Man Rems or Person Sievert But here one needs the effect on an individual or the small group being affected then Rems per man is the proper description (emphasized by the late Rosalyn Yalow, Nobel Laureate who died last week)

Comparison with other disasters

Chairman Gregory Jaczko testimony in US Congress March 17 th 2011 Recently, the NRC made a recommendation that: “Based on the available information that we have, that for a comparable situation in the United States, we would recommend an evacuation to a much larger radius than has currently been provided in Japan. As a result of this recommendation, the ambassador in Japan has issued a statement to American citizens that we believe it is appropriate to evacuate to a larger distance up to approximately 50 miles.”

What should a decision maker have done (my personal opinion)? Order an immediate evacuation for many km ? Make it easy for any VOLUNTARY evacuation – to avoid panic as happened after Katrina Do simple steps to reduce exposure to fall out – including measurement ORDER all out clean up for years Facilitate individual towns and people in voluntary steps Richard Wilson paper in DOSE_RESPONSE (2012): “Evacuation Criteria After a Nuclear Accident: A Personal Perspective” NO YES NO YES

Threshold or linearity? It is important that you understand the argument BUT when dose is low it should not matter But do not in public argue with your supporters who reject the threshold arguments

Alternate Dose-Response Models

Cancer Over Background Excess Dose

Low dose linearity is a general argument Probability of dying in a car accident in Harvard Square is roughly proportional to the number of cars! If the medical outcomes is not distinguishable From one occurring naturally then the argument applies Most cancers Inherent in the multistage theory of cancer Lung effects caused by air pollution

British Journal of Cancer Vol. VIII, March 1954, No. 1 Sir Richard Doll & Peter Armitage (repeated 50 years later) Cancer caused by a series of steps:

Problem is importance for terrorism: (1) Take 1000 Ci medical source (2) Add a few pounds TNT (3) Explode in Wall Street EFFECT: (A) Less than 10 people die (situation in Brazil) (B) 20 square miles out of action THIS MAKES ACTION ATTRACTIVE FOR A TERRORIST Does it matter if Nuclear Power is dead?

Even more important What do you do if someone explodes a nuclear bomb in Boston Harbor? Run away as fast as you can? Take shelter for 24 hours till radioactivity does and listen to which way the wind is blowing? Then if you are in the plume run fast, but which way? Away from explosion? Sideways away from plume? NO YES NO YES

Thank you for listening

Effects of Low Doses Probability of Causation and implications for Public Policy

The Future of Nuclear Power may depend upon a Rational Approach to Risks of Radiation Exposure and their regulation. What are they? Do we compensate those exposed? If not what?

LINEARITY AT LOW DOSES IS USUAL!! Walking blindfold across Harvard Square is safe: (Risk (R) = 0) IF THERE ARE NO CARS! The risk (R) increases roughly in proportion to the number of cars.

Acute Effects Characteristics One dose or dose accumulated in a short time KILLS 1/10 the dose repeated 10 times DOES NOT KILL

CHRONIC EFFECTS including CANCER Characteristics A dose just sub-acute can give effects if repeated. Usually not all people affected - dose response is flatter

Typically an accumulated Chronic Dose = Acute LD 50 gives CANCER to 10% of the population. E.g. LD 50 for radiation is about 350 Rems. At 350 Rems about 10% of exposed get cancer. (more or less depending on rate of exposure)

Early Optimism Based on Poisons There is a threshold below which nothing happens __________ J.G. Crowther 1924 Probability of Ionizing a Cell Linear with Dose

Repair Mechanisms BUT Does the Mechanism Reject/Repair: ALL DAMAGED CELLS UP TO XXXX? (implying a threshold) OR % of CELLS INDEPENDENT OF DOSE WE DON ’ T KNOW

CRITICAL ISSUES FOR LINEARITY The POLLUTANT acts in the same way as whatever else influences the CANCER RATE CANCERS caused by the POLLUTANT are INDISTINGUISHABLE from other cancers

Probability of Causation Come let us Cast Lots to find out who is to blame for this ordeal. Jonah 1:7

Probability of Causation equals Risk from Substance divided by Risk from all Causes

Risk from all causes can be approximated as the Prevalence in a similar Population. If the cancer is rare, POC can be high even if the risk is low.

E.g POC for berylliosis is unity for beryllium as a cause POC for asbestos exposure as a cause of mesothelioma among males is 80% and 20% among females

Administrative Uses of the POC concept: Aluminum workers in Quebec (compensate if POC > 50%) Radiation Workers in UK (compensate if POC >20%)

Compensation for Radiation Exposures Veteran “ Downwinders ” (if upper 99th percentile of POC > 50%; effectively POC >5%) UK Workers (if POC >20%) Old AEC employees (if upper 99th percentile of POC > 50%; effectively POC >5%)

Medical Causation General Causation: the Postulated Cause is Known to Cause the Disease under some conditions (POC>0) Specific Causation, exposure and other circumstances make POC large enough (>50%)

What do the Courts say? US Supreme Court Daubert Joiner Kumho Tire

General Causation needs a Risk Ratio that is significant, statistically and otherwise Usually RR>2 (POC >50%)

Rule to avoid frivolous lawsuits: The postulated cause must be “ more likely than not ” POC>50% But Rutherford instruction If total asbestos exposure is a proven cause, it can be assigned to individual suppliers even if POC < 50%.

RISK of respiratory ailments due to LIFETIME EXPOSURE to AIR POLLUTION is 3 to 5% average in the USA! POC varies from 30% to 80%

If I develop leukemia: The POC from my Medical Exposures would be over 50% Can I sue using the Rutherford case? Minister of Health, UK US State Department Harvard University Commonwealth of Massachussets ONR DOE (AEC)

Assignment of a Cause does not mean that Compensation is payable. E.g. Chemotherapy agents are often carcinogenic and increase risk of future cancers even as they cure.

Go back to the beginning: Does it make sense? Can we study those cohorts where NIH calculate POC near 50%? Risk Ratio of 2? Those x-rayed just post world war II?