From Sr-90 Radiation Hazard to Balancing the Budget

Istvan Gorog

Contents

• Introduction
• Discussion
• Balancing the Budget
• Appendix I -- Units of Measures
• Appendix II -- Some fission products
• Appendix III -- Fission Energy, Bombs and Reactors
• Appendix IV – Long Term Energy Sources 
• Principal Reference Literature

Introduction

A short time ago, a friend asked me whether I knew anything about the radioactive isotope of Strontium, Sr-90, and related public health investigations, known as the “Tooth Fairy Project”. My friend explained that baby teeth provide an indication for accumulated Sr-90 and their analysis indicates excessive radioactivity and cancer risk in the vicinity of nuclear power plants. – At that time I knew nothing about the subject, but I was curious and promised to look into it. The following summarizes my related endeavors and conclusions.

Since the 1950’s, the Sr-90 concentration in baby teeth has been a known indicator of radioactive environmental contamination. The “Tooth Fairy Project”, also known as the “Baby Teeth Project”, is pursued by a group calling itself the “Radiation and Public Health Project” (RPHP). This group, established in 1995 by statistical experts Jay Gould and Ernest Sternglass, focuses on promoting public awareness of links between low-level ionizing radiation and increases in diseases. The group appears to have made useful positive contributions to civil society, though with a strong dose of mistrust of government and a bias towards promoting conspiracy theories.

I first updated my understanding of the underlying physical principles. I reread the basics of radioactivity, nuclear fission, and fission products. I was much interested in gaining an understanding of the fundamental principles as well as developing an ability to perform back-of-the-envelope quantitative estimates related to radioactive fallout from weapons testing and actual and potential nuclear power reactor accidents. Such estimates allow me to crosscheck and verify/deny published statements. Subsequently I searched the available literature (books, public documents, web searches), focused initially on Sr-90 and later expanded to the general question of radiation safety.

To my surprise I learned that today (2011) the greatest radiation danger to public health is presented by medical diagnostic testing, seconded by natural radiation in our environment, followed by residuals from weapons testing and nuclear reactor accidents. A major reactor accident, while not likely, would have devastating consequences in significantly large regions of the globe.

Excessive radiological testing in American medical practice is both harmful and costly. Eliminating unnecessary testing will improve public health and the savings over the next twenty years could contribute Trillions of dollars to the reduction of the public debt.

Discussion

There is no amount of ionizing radiation that is healthy. Every bit hurts. If one bit of radiation shortens one’s life by one day, two bits shortens it by two days. This is now generally accepted as scientifically proven fact. (See Refs. 5, 6, 8-10, 13, 16.)

The following estimates are based on the “linear no-threshold” (LNT) hypothesis.

It is recognized that we humans evolved on an Earth abundant with natural radioactivity and bathed in cosmic rays; the question thus can be raised whether some level of radioactive dose is desirable and only higher levels are of concern. Hormesis and threshold effects had been considered by some studies, but no known scientific data supports an endorsement of such effects in low doses and at low dose rates. Therefore, LNT is the universally accepted scientific approach to assessing the cumulative effects on humans of life-time exposures to ionizing radiation. (Ref. 17) – I did not find a clear definition of low dose and low dose rate. I found (Ref. 6) that diagnostic medical exams may exceed 100 mrem (1 mSv) doses and occupational limits may exceed 10,000 mrem/year (100 mSv/year) dose rates; thus I use these figures as limits for low dose and low dose rates, respectively. As an example of high dose, I found (Ref. 5) that mortality threshold is 150 rem (1.5 Sv) and 800 rem (8 Sv) results in 100 % mortality. (See Appendices for an explanation of some of the technical details.)

Mortality rates that result from exposure to low levels of ionizing radiation vary greatly, depending on the details of the exposure. Nevertheless, a useful quantitative estimate of the danger can be obtained by using an approximate mortality rate of 10^-7/mrem (or 10^-4/mSv) dose. (Refs. 5, 6, 8) This means that the likelihood that in a population of 10,000 people who are all exposed and uniformly receive a dose of 1 mSv, one person is going to die by cancer due to this dose, or alternatively we can expect that the average life in this population will be shortened by 1/10,000-th. If we assume the average life span to be 30,000 days, then average person’s life will be shortened by 3 days due to the 1 mSv dose of irradiation. The worldwide effective dose per person from the residue of weapons tests is continuously decreasing and by the year 2000 it was less than 0.01 mSv (Ref. 10, Annex B, p.397, Figure XXVII); thus its life shortening is on the average less than an hour, but by the same token one in a million people (300 Americans, and 7,000 humans worldwide) will still suffer cancer due to weapons testing (principally American and Soviet) residues. Of course, these statements must be understood in statistical sense: some people in fact will die years prematurely due to cancer caused by the weapons test residues; some will suffer cancer and recover, others may succumb to other ailments and die early due to combination with undetected cancer.

Good data are available on the exposure of the general public to atomic ionizing radiation from all sources and on its evolution over time (Refs. 9 and 10).  The global average annual exposure per person in 2008 was 3.03 mSv. Among the countries with advanced economies the United Kingdom in 2005 reported 2.75 mSv, Germany in the same year 4.04 mSv, and the USA in 2006 6.11 mSv. The principal differences are the results of different levels of irradiation for medical diagnostics. Britain subjected its population to 0.41 mSv, Germany to 1.9 mSv, and the USA to 3 mSv  for medical diagnostic services. It is interesting to note that according to the CIA World Factbook, the life expectancy in the USA is 78.24 years (49-th in the world), in Germany it is 79.4 years (36-th in the world), and in the United Kingdom it is 79.92 years (28-th in the world). Clearly the additional dose of radiation that Americans receive over that of their peers does not enhance longevity. It is of further interest to note that between 1987 and 2006 the annual American per capita diagnostic dose was increased by 1.5 mSv. This increase over a lifetime would result in a total dose of about 120 mSv. Using the mortality rate figure from the previous paragraph, 120 mSv causes a mortality rate of 0.012. Again following the above discussion, a mortality rate of 0.012 means that, in a population of 300 million Americans, on the average 3.6 million are killed by unnecessary radiological medical diagnostics. Or using the alternative statistical interpretation of mortality rate, the average American life span is shortened by one year by excessively aggressive use of radiological diagnostics. The problem of unnecessary diagnostic radiation exposure of the American population is now publicly recognized by medical authorities (Refs.21 and 22).

The maximum annual worldwide per capita effective dose from nuclear weapons testing was about 0.12 mSv. It occurred in 1963 and the recognition of the associated danger to human health led President Kennedy to sign a test ban treaty. As mentioned above, as a result of the test ban the worldwide per capita effective dose from nuclear weapons testing is now about 0.01 mSv per year.

The “Tooth Fairy Project” advocates recently published data (Ref. 1) that indicates levels of Sr-90 concentrations in baby teeth under 10 pCi per gram of Ca. From this I estimate a worst case scenario where the Ca in the average American’s entire skeleton is replaced by Sr-90 in the same proportion as was found in the baby teeth; I calculate an annual dose of about 0.05 mSv. This figure is in a reasonable agreement with the figure in the previous paragraph.

In my view mankind has gone through several distinct phases of understanding and approach to the application of ionizing nuclear radiation.

Phase 1: innocence and reckless ignorance;

Phase 2: promotion and denial;

Phase 3: maturity and preventive designs, public opposition;

Phase 4: quid quo pro public attitude and new national security concerns.

Phase 1 started with the discovery of radioactivity in the 1890’s and ended with the test ban treaty of 1963. This period was characterized by the fact that two Nobel prizes not withstanding, Madame Curie knew nothing about the dangers associated with her discovery and died as a result. Also in this period I worked with radioactive Tritium without any monitoring. For a while shoe stores had X-ray machines for customers to view how their feet fit inside a shoe. This was the time of atmospheric testing and related heavy contamination of down-wind communities.

Phase 2 was characterized by zealous promotion of nuclear energy for non weapon uses. While the first fatal nuclear reactor accident (SL 1) occurred in Idaho in 1961, it did not serve as sufficient warning for design improvement. Numerous small accidents occurred, both at reactors and as results from unauthorized accidental releases of radio-isotopes, for example Indium in Morocco (1984) and Cesium in Brazil (1987). (Ref.16) The US and Soviet governments heavily promoted nuclear power for electricity. Also, both the USA and the USSR carried out programs with much fanfare  for major earth moving excavations by nuclear explosions, see for example Project Plowshare in the US (terminated in 1975) and the Pechora-Kama Canal in the USSR (terminated in 1986). There were a number of small accidents, but this period was terminated by the two major accidents, Three Mile Island in the USA (1979) and Chernobyl in the USSR (1986). It was during this Phase 2 period that the anti-nuclear movement gained momentum. The publications of Jay Gould and his associates from The Radiation and Public Health Project (Refs. 2 and 3) contributed to raising public awareness of actual and potential reactor accidents and their likely cover-ups, even though some of their assertions read today as exaggerations and of questionable scientific merit.

Phase 3 started after the two major accidents. Clearly in the US the state and Federal governments realized that the existing regulatory and engineering safeguards were inadequate to protect the public from potential nuclear accidents By 1990 the Soviet Union ceased to exist and subsequently major American and Russian concerns focused on preventing the illegal dispersion of the ex-Soviet nuclear arsenal. During this period the public in the USA turned anti-nuclear and the development of new reactors came to a virtual standstill.

Phase 4 came after 9/11/2001. The fear of acts of terrorism dominates American, European Union, and Russian policy considerations. A potential terrorist nuclear attack is a major fear. Such an attack is envisioned possibly to take the form of an imported undetected small weapon, a suicide airplane mission or a sabotage action against a reactor, or, but least likely since it is most likely detected and prevented, by dispersal of radioactive contaminants in the environment. To protect the reactors new stringent regulations were put in place in 2007, including hardening of nuclear reactors against airplane crashes. (Ref. 12) The general public attitude now seems to be that everything has a price, if we need nuclear power, let’s build it carefully, but we need to accept certain risks.

The “Tooth Fairy Project” (Ref. 1) revealed no significant new information. The level of radioactivity found in the examined teeth agrees in general with the level expected from well documented residuals from weapons tests. These levels result in doses that are a small fraction of the average American exposure from other natural and man made sources. The subtle differences in the reported Sr-90 content between cancer-free individuals, cancer survivors, and cancer victims do not support causality; in fact the survivors showed less contamination than did cancer free subjects. Overall, The Radiation and Public Health Project currently in 2011 does not provide a needed and credible public service; its time had passed and they appear to be either wanting to profit from past success, or are given to conspiratorial theories, or both.

   Balancing the Budget

Currently a major national debate is raging about Trillion dollar deficits and the historically untouchable sacrosanct quartet of Defense, Social Security, Medicaid and Medicare.

I believe that to rein in medical costs, a fundamental structural change is needed. In America we have a unique arrangement where the fee for service system promotes unnecessary, and ultimately harmful, procedures that benefit the providers and the insurers at the expense of the public payers, and also hurts the patients. Both providers and for-profit insurance companies effectively operate on a basis known in the contracting business as “cost plus”, where both revenues and profits increase with increasing volume. In the foregoing discussion I cited data showing that the average American receives significantly higher doses for radiological diagnostics than do average Germans and Britons, without any known benefit. Patients’ understanding is insufficient to question the providers’ recommendations and private insurers may object in the short run but are happy to comply in the long run, since with increasing fees they profit increasingly. What is needed is a strong government oversight, preferably with a single public payer to protect patients’ interests and put a stop to the unnecessary and excessive procedures. Some call it the “death squads”; so be it, let them call it whatever, but we need it.

There are very powerful forces pushing for ever more testing. First, ever more testing results in a forever increasing revenue stream for all who share in its flow: providers, equipment and drug suppliers, insurance companies. Second, the existing medicolegal system favors action, even if it carries the known risk of future harm, while it penalizes the possible risk associated with inaction. Third, contrary to the well documented evidence (Ref. 22), the public has been sold on the idea that more testing is always good, that testing leads to early detection and early detection is perceived as prevention that results in longevity. Thus the system has a strong positive feedback: the more one looks, the more likely is one to find something unusual that requires more looking and maybe more treatment of something that had no symptoms and most likely would not have developed into an ailment; the general public demands it and the service deliverers are happy to supply it. There is no stabilizing control anywhere in the current system. Society is stuck with an unstoppably increasing bill for services with no benefit and this bill is a major contributor to the public deficit.

Excessively aggressive diagnostic procedures principally use ionizing radiation as the diagnostic tool. There clearly are scientifically sound ways to reduce unnecessary exposures to radiation. The British National Health Service irradiates its population with 2.6 mSv/year lower effective diagnostic dose than received by the average American; nevertheless the British are expected to live more than one-and-a-half year longer. In fact the very concept of the “effective dose”, introduced in 1977, was conceived to allow the assessment of the stochastic risks associated with medical procedures in terms of the known and quantified harmful effects of nuclear radiation incident on the whole body. Current efforts aim at developing procedure and patient specific computer programs to evaluate the Lifetime Attributable Risk (LAR) of cancer associated with radiological diagnostics (Ref. 20).

To put it in financial terms, based on the above comparisons with Germany and the United Kingdom, the average American receives every year over 1mSv unnecessary diagnostic irradiation. Diagnostic procedures vary greatly in dose and cost. The general trend is that the higher the dose, the higher is the cost. For example, a bitewing dental film requires less than 0.01 mSv, a mammogram 0.13 mSv, radiopharmaceutical dose for brain scan 1.7 mSv, CT pelvis 10 mSv. (Refs. 18, 19) Dental X-ray charges are typically $100-150, CT scans cost thousands. Assuming an average diagnostic cost of $1,000/mSv, unnecessary diagnostic radiology costs annually $1,000 per American, or about $300 billion/year nationwide. Eliminating this, in ten years the total savings would be $3 Trillion. Currently Medicare and Medicaid represent about a third of the US national health expenditures; thus in ten years this would contribute a Trillion dollars to balancing the budget. This saving does not include the savings from the reduced medical costs that would accrue from the elimination of the excess 0.012 mortality rate caused by the 1 mSv per year excessive  radiological diagnostics discussed above; the savings from this could be comparable to the direct savings obtained from reduced testing.

Appendix I -- Units of Measures

Activity      1 Curie (Ci)=3.7*10^10 disintegrations/sec

1 Becquerel  (Bq)=1 disintegrations/sec=2.7*10^-11 Ci

Dose            1 rad=100 ergs absorbed by 1 gram

1 Gray (Gy)=1 Joule absorbed by 1 kilogram=100 rad                                                                             

Dose equivalent (biological effect) is equal to dose*Q, for beta rays Q=1

1 rem=10^3 mrem=Q*1 rad   

1 Sievert (Sv)=10^3 mSv=Q*1 Gray =100 rem 

Human composition  (elemental)   ~ 1 kg of Calcium  

7 0 kg total, much of it is water  

~7*10^27 total atoms, ~1.5*10^25 Ca atoms 

Appendix II -- Some fission products 

In the process of nuclear fission the nucleus of a heavy atom, e.g. U-235, breaks up into smaller fragments, i.e. lighter nuclei. The splitting may occur several ways. For example U-235 may split into Ba-144, Kr-89, and two neutrons; these fission products are not stable and will further decay. In the course of his chain of split and decay kinetic energy and radiation (alpha, and beta, gamma rays) are released and the chain ends with the formation of stable nuclei.

The list of all fission products is long and the actual details of the fission yield depend on the fission conditions. Also, as indicated above, some fission products are the secondary decay products of some other primary fission product. For example, Cs-135 is abundant in U-235 yield in weapons and certain types of reactors; it is the result of the fast (nine hours half-time) decay of Xe-135, which is a primary fission product.  About 35 % of the total yield has a half-life greater than one year, including about 13% with a half-life between 10 and 100 years. It is this 10 to 100 year group that presents the greatest long term health risk from residual man-made radioactivity. Cs-137 and Sr-90 are the dominant contributors to the yield in this group.  Some examples of fission products with significant yields are reviewed below, including short and long-lived ones, with comments on their importance as biological hazards.

                      

Fission of U-235 yields ~5.8% Sr-90, which then further decays:

Sr-90 --(29 years)àY-90 + beta(0.55 Mev) --(64 hours)à

Zr-90 (stable) + beta(2.28 MeV) 

Total Sr-90 emission: 2.8 MeV beta with 29 year half-life.

Fission of U-235 yields ~2.8% I-131, which then further decays:

I-131 –(8 days)àXe-131 (stable) + beta(190 keV) + gamma(364 keV)                                       

Total I-131 emission: 0.2 MeV beta and 0.4 MeV gamma with 8 days half-life.

Fission of U-235 yields ~6.9% Cs-135, which has a half-life of 2.3 million-year

and  emits 0.27 MeV beta rays.

Fission of U-235 yields ~6.2% Cs-137, which has a half-life of 30 years and emits 1.7 MeV beta rays and 0.66 MeV gamma-radiation.

Sr-90 is water soluble, direct substitute for Ca in the human skeleton and with a

half-life of 29 years; if ingested, it will be continuously active in a human lifetime; Sr-90 activity is about 5*10^12 Bq/gram =140 Ci/gram; the power emitted is about 1 W/gram =6 mW/Ci and it is the principal man-made contributor to the low-level long-term radiation exposure of humans.

I-131 is easily absorbed in the thyroid and because of its short life it provides an

Intense dose; it may leading to thyroid cancer but is not detectable in patients

since it has decayed by the time of diagnosis; I-131 activity results in high dose exposures within less than a year after its release into the environment and it is not a significant contributor to low-level long-term exposure of humans.

From the perspective of radiological health hazards due to residual contamination

from nuclear weapons tests and accidents Cs-135 and Cs-137 are not as

significant as is Sr-90. Cs-135 has a very long half-life and therefore its

specific activity (activity per unit mass of the active substance, Bq/kg) is very low. The negative health impact of Cs-137 is reduced by its biological half-life.

Biological half-life is the time that one-half of an ingested/inhaled amount of a

substance is excreted by the body. The effective half-life is then given as

                                       

                                                   1/T(effective) = 1/T(physical) + 1/T(biological).

Due to its short biological half-life, the effective half life of Cs-137 in the human body is 0.2 years, while that of Sr-90  is 18 years; thus ingested Sr-90 is accumulated in the body but Cs-137 is excreted. About equal amounts of Sr-90 and Cs-137 are produced in U-235 fission. Both of these substances are water soluble, their dispersion into the environment is similar. For the same amount of daily intake (number of nuclides consumed per day) of Sr-90 and Cs-137, the cumulative damage caused by Sr-90 is close to 100 times greater than that caused by Cs-137.

In the vicinity of nuclear accidents (e.g., Chernobyl), Cs-137and I-131 are major

contributors to lethal radioactivity due to high acute dosages received by the victims immediately after the accident. The principal contributor to long term chronic exposure from residual man-made radioactivity is Sr-90.

  Appendix III -- Fission Energy, Bombs and Reactors

Fission of one U-235 atom produces 2*10^8 eV (200 MeV) energy.

The energy released by nuclear weapons is commonly expressed in terms of the equivalent energy released by a ton of the high energy explosive TNT. The preferred unit of energy in atomic physics is electron-volts (eV). Electric power stations typically generate power at the rates measured in billion-watts (GW) and such stations produce a billion-watt-hours (GWh) of energy in an hour.

1 tonTNT = 2.6*10^28 eV                     

                      = 1.3*10^20 U-235 fissions

                   = 1.16*10^-3 GWh                                   

                =~0.05 gr U-235

The USA and the USSR conducted several hundred, and the United Kingdom a few, atmospheric nuclear bomb tests prior to the test ban treaty of 1963.

In 1963, the USA, the USSR, and the United Kingdom signed the Partial Test Ban Treaty. After 1963, a few bomb tests, mostly underground but some atmospheric,

were conducted by France, China, India, Pakistan, and maybe others. The last

known atmospheric test was done in 1980 by China. [For consideration of radioactive hazards due to fallout, fusion tests (H-bombs) are of secondary interest to fission.] Early fission bombs were “small” ~20 ktTNT devices. If we assume that a total of 100,000 ktTNT equivalent fission tests were conducted prior to 1963 in the atmosphere all using U-235, and ignore the few later tests, then we estimate that a total of ~5,300 kg =1.3*10^28 atoms of U-235 was fissioned, yielding 8*10^26 Sr-90 atoms, that produced 16 million-Ci radioactivity.

The US Nuclear Regulatory Commission, NRC, in its “Backgrounder” (Ref. 11) states that nuclear tests produced 16.8 million-Ci of Sr-90 fallout (Ref. 11); after 50 years (by 2011) this decays to ~5 million-Ci residual radioactivity in the environment.

Power generating nuclear reactors are typically designed for 1 GW scale per unit. According to the 1971 Congressional Record, a 1 GW electrical output nuclear power plant produces annually as much long-lived radioactive fission products as was produced by 1,000 Hiroshima bombs (Ref. 15).

According to the International Atomic Energy Agency (IAEA), in 2010 the global electrical generating capacity of nuclear reactors was about 400 GW. At 30 % fission to electrical energy conversion efficiency, this required 1,300 GW fission reaction. Assuming continuous full power operation, this corresponds to 10^7  GWh/year, or about 10^7 ktTNT/year. Thus, by my estimate, in close agreement with the figure cited above from the Congressional Record, the total global reactor fission energy produced in one year equals 500,000 Hiroshima bombs! This produces every year thousands of times more radioactivity than is the residual from the atmospheric weapons tests. – This is what would be released annually if the fission products were not confined by reactor design. If instead of confinement, this entire Sr-90 yield was released, over the years about 50x the yearly yield, or tens-of-thousands times the residuals from the bomb tests, would accumulate in the environment. This clearly will not occur; clearly a rational person can not say that since all knives can kill someone and everyone has a knife, thus everyone will die by knife. Nevertheless, it illustrates the potential problem associated with accidents. Accidents do occur. In fact, the Chernobyl accident in 1986 did involve a 1 GW scale reactor and  it threw less than a full one-year residue in the air; it added 0.2*10^6 Ci of Sr-90 to the global environment (Ref. 11). (In the immediate geographic vicinity of Chernobyl, the short-term, high-dose radioactivity, in particular from I-131, was responsible for many deaths and illnesses.) – The Chernobyl accident is generally recognized as the second major contributor, after atmospheric weapons testing, to the current level of man-made radioactive environmental contamination, principally by Sr-90 in the fresh-water supply.

The oceans contain 96.5 % of the total 1.3*10^9 cubic-km water on Earth; 1 % is saline in and on the surface; the remainder is fresh water of which about a third is surface and ground water and two-thirds is frozen in glaciers and icecaps. (Ref. 14). Thus the total surface and ground fresh water supply is 10^7 cubic-km = 10^19 liters; it takes about 100 years to recycle this (average annual precipitation is 1,050 mm, or about 10^5 cubic-km over land). Thus, most of the weapons testing Sr-90 residue that fell on the land areas, even if it is now in the water supply, has not yet been washed into the oceans. Assuming uniform fallout, about 1 million Ci Sr-90 residual radioactivity should still be distributed over the continents. Since Sr-90 is highly water soluble, it is reasonable to assume that most of it is now in the fresh water supply. Assuming uniform concentration, we estimate 0.1 pCi/liter fresh water contamination. The US EPA RadNet database shows for Pennsylvania  a maximum reading of 0.5 pCi/liter in July 1979 (the Three Mile Island accident occurred in March 1979); in the last two decades the database shows values fluctuating between 0.05 and 0.2 pCi/liter (Ref. 7). Thus the database values are highly consistent with my estimates. – Neither the database, nor my estimates provide any information on local contaminations that may have occurred due to accidents. For example, I am sure that in the immediate vicinity of the Three Mile Island plant shortly after the accident much higher readings may have occurred than the above cited 0.5 pCi/liter in July 1979. Preventing, minimizing, and containing accidents are not the principal subject of this study. Accidents did and will occur; I am reasonably confident that in the USA the appropriate safeguards are now being pursued. (See the “Discussion” section for the political context supporting this.)

Appendix IV – Long Term Energy Sources

In the long run I do not believe that nuclear is the solution to mankind’s energy requirements. Yes, the accumulating radioactive waste, though confined, is still a potential disaster in waiting and the storage of decommissioned waste is still a not yet solved problem. However, my more fundamental concern is that mankind’s long-term survival hinges on our ability to maintain the thermodynamic balance that provides the narrow environmental window in which we can exist. Large amounts of heat from power plants fueled by stored energy, be it fossil stored by earlier living organisms during the biological evolution of our Earth, or nuclear stored in the nuclei of heavy element during the cosmological evolution of our Solar System, upsets this critical balance. To maintain our survival window, we must rely on renewable energy sources powered by the Sun such that we maintain the existing thermodynamic equilibrium as long as we can. We must not generate more heat on Earth than what we receive from the Sun. This means solar power, be it wind, bio, hydro, thermal, PV, and whatever else we may yet invent.

The most fundamental argument against long term large scale nuclear power deployment is heat balance as stated above. Against long term continued large scale deployment of fossils there are two fundamental arguments: the heat balance as stated above and another one of chemical balance. To state the chemical balance issue simply, the only reason we have the free oxygen in the air that is so fundamental to human life is that we have fossils in the ground. The early atmosphere was hot and all oxygen in it was tied up in the form of oxides, mostly carbon-dioxide (CO2). As the earth and its atmosphere cooled, early forms of life evolved that thrived on CO2. They absorbed CO2, tied down the carbon, and released the oxygen. As we burn fossil fuels, we reverse this process. As we use up fossil fuels, we use up the free oxygen in the air. At the end of this process, we are left with no fossils in the ground and no oxygen in the air. Long before this end, there is not enough oxygen to sustain human life and we yield our place on Earth to sturdier more primitive forms of life.

Assume that at some time in the future there are 10 Billion people living on Earth, each consuming 100 kWh/day, less than one-half of the current per capita consumption in the USA. Then it would take about 10 thousand years to use up all the oxygen in the air for the purpose of supplying the global energy need from fossil fuels. Of course, in a fraction of these ten thousand years the composition of the atmosphere would cease to be suitable for sustaining human life. Thus under such a scenario the future of humanity would be shorter than our historic past known from written documents.

Principal Reference Literature

(1)             “Cancer Risk to Americans from Atomic Test Fallout – A case Control Study of Strontium-90 in Baby Teeth”, Joseph J. Mangano, October 20,2009, paper published on the web site of the Radiation and Health Project

(2)             “The Enemy Within”, J. M. Gould, Four Walls Eight Windows, New York/London, 1996

(3)             “”Deadly Deceit”, Jay. M. Gould and Benjamin A. Goldman, Four walls eight Windows, New York, 1990

(4)             “Physical, Biological, and Effective Half-lives for Selected Isotopes”, web page of “hyperphysics.phy-astr.gsu.edu”

(5)             “Cancer RSK Estimates” on web source  from: Princeton University, Open Source Radiation Training, Module 3, Biological Effects, princeton.edu/sites/ehs/osradtraining/biologicaleffects

(6)             ‘Radiation and Risk”, on web source from: Idaho State University, Radiation Information Network, physics.isu.edu/radinf/risk

(7)             Queries of EPA Envirofacts Warehouse RadNet for radioactive contamination data of pasteurized milk and drinking water

(8)             “Estimating Radiogenic Cancer Risks”, U.S. Environmental Protection Agency document EPA 402-R-93_076, June 1994

(9)             UNSCEAR 2000 Report of the United Nations Scientific Committee on the Effects of Atomic Radiation to the General Assembly, December 16, 2008

(10)        UNSCEAR 2008 Report of the United Nations Scientific Committee on the Effects of Atomic Radiation to the General Assembly, July 20, 2010

(11)        “Radiation protection and the “Tooth Fairy” Issue”, U.S.NRC Backgrounder Office of Public Affairs, on NRC web site, December 2004

(12)        “Radiological Effluent Release Dos Consequences from Normal Operations”, nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1923/sr1923-ch11, from an NRC staff review of the Exelon Generation Company, LLC (EGC or the applicant) early site permit, undated, in compliance with Federal Regulation 10 CFR 52.17(a)(1)(iv), after September 27, 2007

(13)        “Dose Chart”, American Nuclear Society, available on ANS web site, Public information Resources, new.ans.org/pi/resources/dosechart

(14)        “Where is Earth’s Water Located?” USGS Water Science for Schools, available on the web at usgs.gov/edu/earthwherewater

(15)        “The Fission-Product Equivalence between Nuclear Reactors and Nuclear Weapons”, John W Gofman, adapted from Vol. 117, No. 105, July 1971, of the Congressional Record, on the web at ratical.org/radiation/CNR/fission.html

(16)        Numerous searches on Wikipedia for information on fission physics, weapons testing, reactor accidents, other accidental releases of radioactive contamination, test ban treaties, and other related technical and political issues

(17)        “BEIR VII: Update on the risks of low –level radiation”, overview of the main findings by Arjun Makhijani, July 19, 2005 on the web at ieer.org/latest/beir7presentation (BEIR is an acronym for Biological Effects of Ionizing Radiation, the series of BEIR studies were undertaken jointly by the National Academies)

(18)        “Doses of Medical Radiation Sources”, Michael G. Stabin, on a Health Physics Society web page, last updated 18 December 2009, hps.org/hpspublications/articles/dosesfrommedicalradiation

(19)        “Radiation Dose Chart”, ANS Public Information, new.ans.org/pi/resources/dosechart

(20)        “Relative Effective Dose Risk Based on Medical Diagnostic Modalities at the Nebraska Medical Center”, Michael D. Petrocchi, Oregon State University, June 7, 2010, ir.library.oregonstate.edu/xmlui/handle/1957/17400 

(21)        “Treat the Patient, not the CT scan”, Abraham Verghese, The New York Times, Week in Review p10, Sunday, February 27, 201

(22)        “Overdiagnosed, Making People Sick in the Pursuit of Health”, Dr. H. Gilbert Welch, Beacon press, Boston, 2011

Prologue: why?

I always enjoyed learning about things and about what makes the world go around.

I like to make quantitative estimates, not precise calculations, but simply physically meaningful approximations.

I also like to write things up because in the process of putting things down in writing I discover things I missed, holes in my thinking that I can then correct. Since I have my thoughts in writing, it is easy to share them with others. Also, I would like to join the public debate on some issues. Thus the idea of this blog was borne to post my white paper "From Sr-90 Radiation Hazard to Balancing the Budget"; I started out in one direction and wound up where I was not heading. Other posts may follow later.