Charting the Isotopes in Fallout

Nuclear explosions over the past 60 years dispersed throughout Earth's atmosphere radioactive chemicals that settled in our food and water, and collected in everyones' bones, teeth, muscles and essential bodily organs. But if all people across the Earth have this one health-risk in common, then wouldn't you think it has been already vigorously studied? Or a topic for high school or college students? Or medical students?

Sadly, there is very little attention - relative to their destructive power to the human race - given in medical studies or education to these radioactive contaminants. Their destructive power lies in their longevity and ubiquity in our world, despite their miniscule quantities. These long-lived radioactive products from nuclear testing continue to poison the consumables in our watersheds, milk-sheds and food-sheds, yet so little is known about the impacts on human health.

So, why not learn about the 'isotopes' in fallout...since they are part of you! They're in your legs, your hair, your liver and your brain. Why not see what they're all about...

Natural radioactivity

What is Radioactive Decay?

Decay is usually chronicled in 'half-lives' but that is a very misleading term. For instance, the half life of Iodine-131, which was created in enormous quantities by nuclear weapons testing in Nevada (and weapons production, for example in Washington State), is 8.02 days.

What this means is that in 8.02 days, one would expect that half of any quantity of Iodine-131 will decay. The problem with the term 'half-life' is that one has to ask how did one-half of a given quantity of Iodine-131 decay in 8.02 days while the other half remained undecayed?

Half-life doesn't mean technically that a given quantity of Iodine-131 becomes half as radioactive every 8.02 days. It means that one-half of Iodine-131 has decayed in 8.02 days and the other half hasn't.

So, this is really all about probability. A half-life is a simplified way of talking about probability. The half-life of Iodine-131 is really the odds - or, 1 in 2 - that any radioactive Iodine 131 atom will decay in a period of 8.02 days. In 8.02 days, the 'odds' are that half of the atoms would have decayed, as one would expect in 8 coin tosses that we'd come across 4 heads and 4 tails.

It doesn't always work that way. Sometimes we get 5 heads in 8 tosses, other times we may get none. And that's why half-life is really a game of chance.

There are ways to calculate how much so and so will decay by so and so a time, however they involve logarithmic functions. It is very easy, however, to calculate off the top of our heads how much of an amount of a radioactive element is left after 2 or 3 or more half-lives. Simply put, assuming that probability 'plays a perfect game,' at 1 half-life, half is left. At 2 half-lives, one-quarter of the original quantity is left. At 3 half-lives, one-eighth is left, etc...

The most toxic substance in the universe, Plutonium 239, has a half-life of 24,000 years. So it will take 24,000 years for it to decay by half, and 48,000 years to decay to one-quarter of the original levels. The question of how many 'half-lives' equates with a 'safe' level is disputable. Some say ten half-lives, others put it at much more. So, Plutonium-239 may be dangerous to human health for more than 240,000 years.

What makes something radioactive?

First of all, the building block of everything that has mass is the atom, and every atom is also called an 'isotope' of some chemical element. The difference between radioactive isotopes and non-radioactive elements is that radioactive isotopes don't have the same number of neutrons as protons. This imbalance results in atomic instability in most cases, but not all.

Do radioactive isotopes exist in nature?

There are some naturally occurring radioactive elements. For over a billion years the Earth's crust has contained naturally occurring radioactive Uranium, and various other radioactive elements that are produced by Uranium's 'decay,' such as Polonium, Thorium and Radon. Commonly known naturally occurring radioactive elements include Radon, Uranium-235 (used in nuclear applications), and Uranium-238 (the main ingredient in Depleted Uranium).

Actually any naturally occurring element (remember the 'periodic table?') with an atomic number higher than 82 is radioactive⁺.

What about man-made radioactive isotopes?

Every single human-made radioactive isotope is unstable. So, although stable and unstable radioactive isotopes exist in nature, only unstable ones have been added to nature by human activity.

Over the past 60 or so years, the 'background levels' of our globe have been increasingly 'overcrowded' by man-made fission products from nuclear weapons testing⁺⁺ and weapons production and other nuclear energy activities.

'Fission products' are man-made radioactive isotopes of over 100 ordinary elements found in nature. As these unstable radioactive isotopes decay, they give off radiation - alpha, beta or gamma rays - that can cause damage to any form of life. These radiation rays are the result of a decay process that turns an isotope into a 'daughter' isotope!

What is a 'daughter' isotope?

Unstable radioactive isotopes give off neutron, gamma, beta, or alpha rays as they decay into some other isotope. Take Depleted Uranium for example. Natural uranium-ore, which is mined and milled for the extraction of Uranium-235 (for nuclear bombs and power plants), consists of over 99% of Uranium-238. That 'residue' of Uranium-238 is not needed and so considered scrap, and dubbed 'Depleted Uranium.' Uranium-238 (U-238) emits alpha radiation as it decays (its half-life is 4 billion years!) into a succession of 14 different radioactive isotopes! Each 'daughter' of U-238, all radioactive isotopes, gives off different kinds and intensities of radiation. Some give off alpha and beta rays that primarily do damage to cells if ingested internally. Others emit gamma rays, which are more penetrating than even X-rays! There are even trace amounts of radioactive plutonium-239, americium-241 and neptunium in some 'batches' of depleted uranium used in munitions that are even more dangerous to health (internal exposure) than most of the 'daughters' of Uranium-238. The 'decay-chain' of U-238, as follows, is complex, but it ends as Lead-206, which is a stable isotope (not radioactive). All radioactive isotopes eventually decay into some stable isotope.

U238 --> Th234 --> Pa234 --> U234 --> Th230 --> Ra226 --> Rn224 --> Po218 --> Pb214 --> Bi214 --> Po214 --> Tl210 --> Pb210 --> Bi210 --> Po210 --> Pb206 See a partial flow-chart of this decay on a chart-of-nuclides

⁺These include elements with the symbols Bi (Bismuth), Po (Polonium), At (Astatine), Rn (Radon), Fr (Francium), Ra (Radium), Ac (Actinium), Th (Thorium), Pa (Protractium), and U (Uranium). Any element with an atomic number greater than 92 is called a 'Transuranic' element and actually does not occur in nature. Uranium, atomic number 92, is the heaviest natural element found on Earth. Heavier 'transuranic' elements than Uranium are created by human 'fiddling with the atom.'

⁺⁺Over 9 million grams of fission products - products of a nuclear explosion - were blasted into our atmosphere during Cold War testing from the 1950s to the 1990s. Fallout from thousands of nuclear tests - both above-ground and leaky underground tests - reached all continents. It fell onto fields, lakes, oceans, crops, houses, and all living things. Nuclear fallout is still present in soil and present-day food products and small portions of it are continually being incorporated into our food supply. A sizeable portion of the radioactive toxins from Cold War nuclear testing still remains in aerosol form - it is in the air around us. Although fallout from nuclear testing is only about 40-50 years old in most cases, there is a considerable amount of it, in addition to plutonium and DU, in our living environment - our air, soil, water and food - that won't safely decay for hundreds or thousands of years.

A U.S. government health study released in 2002 stated regarding fallout from nuclear weapons testing: "Any person living in the contiguous United States since 1951 has been exposed to radioactive fallout and all organs and tissues of the body have received some radiation exposure." So, if you were born in the contiguous U.S. since 1951, you have radioactive fallout in your body and will always have these toxins in your body from recurring exposure. This will be no different for your children, grandchildren, and great grandchildren, etc... because our food/water/air will be constantly re- contaminated from radioactivity from other hotspots around the globe. All of this radiation has increased our collective cancer burdens, and of future generations.

Fallout, when in the body - either through inhalation or ingestion - takes months to hundreds of years to be flushed out. Cesium 137 and Strontium 90, which both have a half-life of about 29 years, will take 200-300 years to decay to 'safe' levels but vary greatly in their biological half-life. (Safe levels may be defined as 10 half-lives at which time the original number of radioactive atoms is reduced by a factor of 1000; 10 half-lives is only 1/2 of the whole lifetime of the radioactive element; some say 20 half-lives renders a safe level). The biological half-life^** of cesium-137, which is a substitute for potassium (used in physiological functions), is about one to four months whereas that of strontium-90, which behaves chemically much like calcium, is very, very long - it can be incorporated in the bone for a lifetime. Plutonium 239, radioactive for over 200,000 years, when in the body has a biological half-life of 20-50 years.

^**The biological half-life of a substance is the time required for half of that substance to be removed from an organism by either a physical or a chemical process.

It's only fair to first state there are radioactive elements found in nature. These include 'isotopes' (isotope is simply a word to distinguish one atomic element from another) of Uranium and its 'daughters.' 'Daughters' simply alludes to those isotopes that uranium becomes as it travels on its very long journey to become 'stable' and non-radioactive lead. Those daughters include isotopes of thorium, radon, radium, polonium, lead, bismuth, and protractrium. These such substances, all radioactive and natural (!), are found everywhere in nature, however are generally weakly 'energetic' radioactive isotopes compared to artificially-created ones.

In the 1930s and early 1940s, scientists began creating new radioactive isotopes during small experiments. Then, in 1945, 'we' commenced nuclear testing, and those new radioactive isotopes created in small experiments before 1945 were spewed and scattered far and wide in huge nuclear explosions conducted on nearly every continent.

Human's did a remarkable, but very, very stupid, thing: they split the atom (without knowing what would happen medically if it ever ended up our bodies). When the atom was split, the above-listed natural radioactive elements were supplemented with a new set of deadly friends, or new radioactive 'isotopes.'

In a nuclear explosion, Uranium (or plutonium) is violently bombarded with particles called neutrons which starts a chain reaction. This chain reaction releases a tremendous amount of energy as the Uranium 'splits' or 'fissions' itself into new radioactive elements, all not found in nature.

This atomic-splitting process adheres to some strange rules. One is that uranium (or plutonium) doesn't break apart into equally, or symmetrically, similar halves. Rather, its fissioning occurs in 30 or 40 different ways. As such, the pieces (like shards of glass) from the original uranium end up in various sizes, or 'masses,' and very rarely in exact or near exact half-sizes of uranium.

When speaking of atoms, we talk of 'mass,' which is the term given to the weight of an atom, equal to the sum of the number of neutrons and protons. Interestingly, 100% of the masses of the 'fission products' from a nuclear explosion from Uranium (which has a mass of 235) are between 71 and 161. So, another strange rule is there is a limit on how small an isotope and how big an isotope that a uranium chain reaction can produce.

What's more is that 97% of the fission isotopes from uranium have masses between 85 and 104, and 130 and 149. This peculiarity is depicted in the below mass-yield distribution curve.

Each of these new fission isotopes from fissioning uranium has similar properties to the ones found in nature - they are like 'elemental' Selenium, or like 'Iodine,' or 'Calcium,' but they have become radioactive! They have become radioactive by being bombarded by, and also have absorbed extra, neutrons. (Neutrons are the key to the chain reaction, and they are created in dizzying quantities.)

Elemental isotopes, like Iodine-127 (the stuff found in seaweed, and first aid kids) are not radioactive because they have about the same number of protons as neutrons. But, during the neutron-frenzy in the chain reaction of nuclear explosion, isotopes are created with too many neutrons compared with protons, and they become unstable for this reason.

Another strange rule is that every isotope wants to become stable if they find themselves unstable, and they accomplish this through 'decay'. Being stable means having a similar number of neutrons to protons. With the 'lighter' isotopes (those isotopes with masses between 85 and 104), they become stable through a type of decay called 'beta decay,' which is simply the process whereby a neutron 'decides' to break itself apart to become a proton particle and an electron particle. So, all of the 'lighter' fission products with too many neutrons use the 'beta decay' process to rid themselves of extra neutrons. They do this by 'converting' the neutrons into protons.

What happens, when an atom takes on extra protons by beta-decay, is that the isotope becomes a new element! Let's take Iodine. Iodine (found in seaweed and first aid kits) has a mass of 127 - it has 53 protons and 74 neutrons. And as long as it keeps 53 protons, it will always remain Iodine because that is Iodine's atomic number. But when Iodine takes on extra protons through beta-decay, it can become Barium! How? Assume an atomic explosion creates Iodine with 11 extra neutrons, or Iodine-138 (53 protons and 85 neutrons). The beta-decay process will turn the extra neutrons into extra protons, and after several 'stages' of decay (I-138 > Xe138 > Cs138 > Ba138) it will become Barium-138, which is one of several stable isotopes of Barium (although not really used much for anything)!

Sometimes a fission isotope will decay through alpha-decay. Alpha-decay is more common with the 'heavier' fission products (masses 130 through 149) and is simply the ejection from the atom of two neutrons and two protons (which is actually a Helium atom or ₂He⁴).

Another type of decay is 'neutron decay,' which is simply the loss of a neutron particle - neutron decay doesn't change the element, just the mass (i.e. as Krypton 87 decays, it spits out a neutron to become Krypton 86).

There is another thing that happens with some decaying radioactive isotopes that isn't decay itself but pure energy. It is when the nucleus of an atom needs to blow off some steam (get rid of extra energy). This is called 'gamma' activity. Gamma rays are very, very similar to X-rays, just a bit stronger!

Trying to make sense of all the radioactive isotopes dispersed throughout the world from nuclear testing is daunting. The most commonly discussed fallout isotopes are Iodine-131, Cesium-137, and Strontium-90. But there are HUNDREDS more, most short-lived, but also some long-lived - and still quite radioactive in our ecosystems.

Perhaps the best way to make sense of all those fallout radiological isotopes that are busy 'insulting' our bodies on a daily basis is through the 'Trilinear Chart of Nuclides.' The original chart by that title was created by William Sullivan for the Atomic Energy Commission in 1957. (It is currently out of print, but can be purchased for $40 online.)

Below is an adaptation of it - and a work in progress. It includes a bigger scope of the 'lighter' fission isotopes, from mass numbers 84 to 105. We are currently working on the heavy-isotope chart too! And, we're working on adding the 'meta-stables' on both charts (more on that later).

The chart is called 'tri-linear' because it ingeniously has three streams of information that travel along straight...lines. One data stream includes the (slanted) horizontal lines containing isotopes with the same atomic # (same # of protons). Another includes the vertical lines with isotopes of same mass numbers. And the last is the diagonal lines, or 'isotone lines' (going from upper left to lower right), that shows isotopes with the same number of neutrons.

There is yet another 'line,' called the 'line of stability,' which includes isotopes that have a 'safe' or 'stable' ratio of protons to neutrons - these don't spontaneously decay and are isotopes occurring in nature. We also call these elemental isotopes.

Here is a photo taken of a section of Sullivan's original tri-linear chart onto which we drew some stuff on about decay of Uranium-238.

The advantages of this kind of chart is that one has a visual inventory of the 'fallout isotopes,' and one can easily pinpoint the long-lived ones. Accordingly, one comes to question the effects of these long-lived toxins: 'what does Zirconium-95' do in our bodies?.' The only fallout isotopes studied by federal health agencies has been Iodine-131, yet the 131-mass chain represented only about 2% of the yield of nuclear fission explosions. In 2001, Richard Miller, who has long studied U.S. testing fallout, wrote an oped letter to the editor of a mainstream newspaper recommending a study of the radionuclides other than Iodine 131(or I-131). Miller wrote: 'I131 accounts for only 2 percent of the radionuclides from fallout. Those that should be studied should include: Be7,Au198, Au199, Mn54, Co60, Fe59, Ag109, Nb95, Nb95m, Sr89, Sr90, Y90, Y91, Pb103, U239, U240, Am241, Cm242, Zr95, Rh106-Ru106, Ce144-Pr144, I-130, I-132, I133, I135, Na24 and Tb161.' Although Miller proceeded to complete his recommended study on his own for several Midwestern states and has demonstrated some compelling correlations between isotopes and specific health problems, there is still a huge question mark over the fallout isotopes in both the light and heavy lobes ('rabbit ears') of the fission-mass-yield curve. How did Miller tabulate the above list of worrisome-radioisotopes? Well, for the lighter-nuclide 'rabbit ear,' it is obvious that the ones he listed - Nb95, Nb95m, Sr89, Sr90, Y90, Y91, Pb103, Zr95, and Rh106-Ru106 - are all fallout isotopes that would hadn't decayed by the time they traveled to off-site areas. Clearly, a tri-linear chart of nuclide is a fabulous tool for understanding the toxins that affected and are still affecting downwinders from nuclear testing.

Idealist's public document archives: 1. 2.

U.S. NUCLEAR tests: 128 A + 899 U in NV,
1 A in NM, 10 U (in NM, CO, AK, MS, central NV),
100+ A, U in Pacific, 3 A in S. Atlantic
(A=aboveground; U=Underground)

'The greatest irony of our atmospheric nuclear testing program is that
the only victims of U.S. nuclear arms since World War II have been our own people.'
- Forgotten Guinea Pigs Report, 1980

In 1986, the U.S. Dept. of Energy used the cover of the Chernobyl fallout cloud over the United States to release huge amounts of radiation into the air from a failed underground Nevada nuclear test. It was called Mighty Oak.

Did global fallout cause massive mutations that may explain disorders like autism?

learn more on our global fallout page

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20 Radioactive Dangers We All Face
1. Nuclear reactors crashing on Earth from space and fallout from: 2. Pacific nuclear testing 3. the Nevada Test Site 4. High-altitude nuclear tests 5. Project Rulison 6. Mighty Oak nuclear test 7. North Korea's nuclear tests 8. Global nuclear testing 9. 'Project 57' (Area 13) 10. Trinity, WSMR & Steel	11. Hanford & INL & LANL 12. Nuclear Power 13. DTRA's Divine Strake's babies 14. Fallout resuspension: Milford Flat Fire 15. Australia's fallout and duststorms 16. Hiroshima & Nagasaki -and- 17. Low-level radiation impacted viruses 18. Radioactivity in drywall (dust) 19. Nuclear waste transport 20. Greenham Common