Radiation Explained In Layman Terms and How To Protect Yourself If Exposed Print
Written by Dee McCaffrey, CDC   
Friday, April 08, 2011

The radiation leaking from nuclear power plants in Japan have us all concerned, and rightfully so.  Most of us know that exposure to radiation is very hazardous, even in low doses.  But most of us don't know exactly what radiation is and why it's so harmful.


I have to admit that I had to reach to the recesses of my brain for those old files from college chemistry and physics courses on radiation.  When my husband asked whether or not what the TV reporters were saying was accurate, I couldn't answer with certainty. 


The memory of what I learned about radioactive elements in college was hazy, so I went to my computer and spent hours and hours on the internet refreshing myself on the basics.  In this article, I will explain to you in simple terms, how radiation is formed, when and why it's dangerous, and the steps you can take to protect yourself.


You'll have to bear with me, as I make no apologies for the length of this article.  To understand radiation and why it's harmful, you need to know a few things first.


 How Nuclear Power Works


All power plants require some way of creating heat, or energy,  to boil water. The boiling water creates steam that is used to turn a turbine. As the turbine spins, the generator turns and its magnetic field produces electricity. The electricity is then carried through power lines to all of the places we use it.


 Some power plants burn coal or oil for heat to boil water for making steam. At nuclear power plants, the heat used to boil the water is created when atoms are split apart -- called nuclear fission. 


An atom is the smallest form of matter in the universe. Matter is anything that can be touched physically. Everything in the universe (except energy) is made of matter, and, so, everything in the universe is made of atoms.


An atom itself is made up of three tiny kinds of particles: protons, neutrons, and electrons. The protons and the neutrons make up the center of the atom (called the nucleus) and the electrons fly around above the nucleus in a small cloud. The electrons carry a negative charge and the protons carry a positive charge. Neutrons have no charge. 


 Within an atom, the negative electrons are attracted to the positive nucleus by the same type of electrical force that causes magnets to work. That's what holds atoms together and prevents them from splitting apart.diagram


In a stable atom the number of protons and the number of electrons are equal. Often, but not always, the number of neutrons is the same too.  For instance, a carbon atom has 6 protons, 6 neutrons, and 6 electrons.  An iodine atom has 53 protons, 74 neutrons, and 53 electrons. When you add the number of electrons to the number of neutrons, you get the atomic mass (weight).  Therefore, carbon has an atomic mass of 12, and iodine has an atomic mass of 127.


There's another term you might have heard of - isotopes.  An isotope is a variant of a particular atom that has a different number of neutrons but always the same number of protons.  For example, carbon-12, carbon-13 and carbon-14 are three isotopes of the element carbon with atomic masses of 12, 13 and 14 respectively. The atomic number of carbon is 6 (every carbon atom has 6 protons); therefore the neutron numbers in these isotopes are 6, 7 and 8 respectively.


Other elements, such as iodine, can also have isotopes. 


Hold those thoughts while I explain what radiation is.


What is Radiation?


Like with most things in science, it gets a bit complex, but radiation is basically a form of energy.  "Radioactivity" is the term used to describe the natural process by which some atoms spontaneously disintegrate, emitting both particles and energy as they transform into different, more stable atoms. This process, also called radioactive decay, occurs because unstable isotopes tend to transform into a more stable state.


There are two distinct types of radiation; ionizing and non-ionizing. Ionizing radiation means that the energy being emitted is powerful enough to ionize atoms, meaning to break atoms into its parts.


Non-ionizing radiation does not have enough energy to break atoms, but can only excite them to a higher energy state.  Electromagnetic waves, ultraviolet light, visible light, infrared, microwaves, and radio waves, are all examples of non-ionizing radiation.  The light from the sun that reaches the earth is largely composed of non-ionizing radiation, with the notable exception of some ultraviolet rays.


The word radiation is commonly used in reference to ionizing radiation only, but it may also refer to non-ionizing radiation such as radio waves or visible light.  Both ionizing and non-ionizing radiation can be harmful to organisms and can result in changes to the natural environment.  Ionizing radiation is potentially very hazardous to our health, because once it gets in or near our bodies, it can ionize our cells and the atoms that make up our DNA.


A substance is classified as "radioactive" when it is emitting ionizing radiation.  For example, uranium is a naturally occurring radioactive isotope that has been on earth since the planet was formed.  In its natural form, uranium is unstable, therefore it spontaneously emits, or "throws off" neutrons from its nucleus in order to become stable.


Uranium is a natural choice for nuclear power plants, because in order to split other atoms apart to create heat, a neutron is needed to get the reaction going.  The neutrons that spontaneously emit from uranium are used to split atoms of iodine, plutonium, and cesium, among others.  This induced chemical reaction is called nuclear fission, which takes place when the nucleus of an atom is split in two when it is struck by a neutron from another atom and releases energy in the form of heat.


While all of this may sound like great science, problems abound.  Exposure to this type of ionizing radiation causes damage to living tissue, resulting in skin burns, radiation sickness and death at high doses.  Low dose exposure causes cancer, tumors and genetic damage.


I know this is a lot of information, but stick with me. I'm now going to tell you why the iodine that is being detected in milk and the environment is something to be concerned about.



Background Radiation, What is it Really?


The media keeps telling us not to worry about the radioactive iodine that has been detected in milk and in the environment.  TV reporters say radiation is everywhere, that it's been part of our environment since the planet was born. They say radiation exists in the atmosphere, the ground, the water and even within our own bodies. It's called natural background radiation, and so far, they are saying, detected levels are normal and far below anything we should be concerned about.


According to Patricia Hansen, an FDA senior scientist, Radiation is all around us in our daily lives, and these findings are a miniscule amount compared to what people experience every day. For example, a person would be exposed to low levels of radiation on a round trip cross country flight, watching television and even from construction materials.


In fact, you can check the EPA website and the Radiation Network website to get up to date information on background radiation levels in sites all over the country.  They have maps with all the places in the country where monitoring stations are set up, and what the most recent detection levels are.


But there's a flaw with this information.  The type of background radiation being monitored  does not discern between the type that comes from non-ionizing radiation and ionizing radiation.  There is no way to know if we are being exposed to visible light, radio waves, or the kind that comes from induced nuclear fission. And there's a big difference.


The splitting of atoms creates intense heat and ionizing radiation coming from radioactive isotopes affects our bodies by depositing energy in our tissues, which can cause damage to our cells and DNA.


There are four types of ionizing radiation that we can come into contact with in our normal environment: (1) alpha radiation, (2) beta radiation, (3) gamma rays, and (4) neutrons.



  • Alpha emitters are isotopes that emit alpha particles. Alpha particles are the most destructive form of radiation compared to others such as gamma particles and beta particles. While alpha particles are the most destructive form of radiation, they also have a low penetrating force. Alpha radiation can be stopped by a piece of paper and poses a concern mainly when it is emitted inside the body (I will discuss this a bit later). When the alpha emitter is on the surface of the skin, the dead layer of the skin adequately protects the body from harm by trapping the emitted alpha particles.  However, if the skin has a wound, the alpha emitter can enter the body through the wound and cause harm.  Also, if the alpha emitter is ingested through food or drink, it can cause harm. Examples of some alpha emitters: iodine-131, radium, radon, uranium, and thorium.


  • Beta emitters are isotopes that emit beta particles.  Beta radiation can pass through the dead layer of the skin and cause harm to the body if the body is not protected. Beta radiation can be stopped by aluminum.  Clothing can provide some protection from beta radiation injury to humans when the beta emitter lands on the outside of the clothing. Beta emitters that are inhaled into the lung or ingested into the gastrointestinal tract can cause harm.  Examples of some beta emitters: strontium-90, carbon-14, tritium, and sulfur-35.


  • Gamma rays can go through the entire body if not protected and can damage multiple organs.  Gamma rays can be diffused by lead (which is why lead aprons are used to protect you when you're getting a X-ray).  Gamma emitters that land on the outside of the body and those taken inside the body both can cause harm.  Clothing provides little protection from gamma rays. Examples of some gamma emitters: iodine-131, cesium-137, cobalt-60, and radium-226.


  • Neutrons are the only type of ionizing radiation that can make other objects, or material, radioactive. This process, called neutron activation, is the primary method used to produce radioactive sources for use in medical, academic, and industrial applications.  High-energy neutrons can travel great distances in air and typically require hydrogen rich shielding, such as concrete or water, to block them. A common source of neutron radiation occurs inside a nuclear reactor, where many feet of water is used as effective shielding.  Neutrons can penetrate deep into the body, and while doing so, can produce gamma rays through their interaction with tissue atoms.  Thus, all neutron exposures involve some gamma rays. Clothing provides essentially no protection from neutrons.


The below diagram illustrates the relative abilities of three different types of ionizing radiation to penetrate solid matter. Alpha particles (α) are stopped by a sheet of paper while beta particles (β) are stopped by an aluminium plate. Gamma radiation (γ) is dampened when it penetrates matter. 



So, the maps showing levels of radiation are helpful to be able to check if radiation levels are rising in your area, because this could be due to radiation coming from Japan. But unfortunately low doses of radiation can be just as harmful, contrary to what we are being told.


Stable Iodine versus Radioactive Iodine


Iodine exists in nature as a stable isotope.  It is not radioactive.  It is relatively rare, yet it is essential for life in many species, and especially for the functioning of the thyroid gland in humans and animals.  Because of its rarity, about 2 billion people are iodine deficient. 


When naturally stable iodine gets struck by neutrons during induced nuclear fission, it forms an unstable (or radioactive) isotope.  The iodine-127 mentioned above, absorbs 4 neutrons into its nucleus, creating iodine-131.  Iodine-131 is radioactive because it is not stable.  It wants to revert back to being Iodine-127, so it "throws off" those 4 four neutrons in the form of ionizing energy.  But the "decay" takes time, it doesn't happen all at once.  The rate of decay is measured in terms of a half-life. 


What's a Half-Life?


Half-life is a measure of the time it takes for one half of the atoms of a particular radioactive isotope to disintegrate (or decay) into a more stable form.  The half-life of radioactive iodine-131 is 8 days.  That means it takes 8 days for half of it to decay. 


Let's say you have a pound of radioactive iodine - it would take 8 days for a half pound of it to decay.  You would then have a half pound of radioactive iodine left. It would then take another 8 days for half of that to decay, leaving still a quarter pound.  Then another 8 days for half of that to decay and so on until all of it has been transformed back to iodine-127.


The Problem With Radioactive Iodine


It might sound safe that radioactive iodine has a short half-life of only 8 days.  But what happens if you get some of that radioactive iodine into your body before the 8 days are up?  Our bodies can't tell the difference between a radioactive form of iodine and a stable form.  In fact radioactive isotopes of any element will get used by nature and by our bodies as if it were not radioactive. 


So, if you ingest radioactive iodine by breathing it or by drinking contaminated milk or water, EVEN IN LOW DOSES, that radioactive iodine will be taken up by your thyroid gland, especially if you are deficient in iodine already.  Research has shown that over 95 percent of Americans are deficient in iodine.


Once it has taken hold in your thyroid gland, it's bad news.  Radioactive iodine is an alpha-emitter, the most destructive kind of radiation.  It will emit ionizing radiation directly into your thyroid.  This would be the equivalent of getting a serious dose of radiation directed into your thyroid continuously for 8 days (and longer due to half-life) without any protection! This is why iodine-131 is one of the most carcinogenic nuclear fission products.


You also have to keep in mind it is not just the thyroid gland that is at risk with exposure to radioactive iodine. The breasts, ovaries, uterus, prostate, skin, and other organs all require iodine.  In fact, every cell in our body requires iodine for optimal functioning. Therefore, if we are iodine deficient, exposure to radioactive iodine can potentially result in damage to all the cells of the body.


What You Can Do to Protect Yourself


You may have heard about stores selling out of potassium iodide tablets.  Taking these tablets saturate your thyroid gland with stable iodine and prevent radioactive iodine from filling iodine receptors in the thyroid gland.


It's important to understand that potassium iodide offers no protection from direct radiation exposure or OTHER airborne radioactive particles like cesium, plutonium or uranium.


However, you can and should protect yourself by saturating your thyroid with potassium iodine or another form of iodine if you have any fear that you may come into contact with radioactive iodine.  BUT YOU MUST DO IT BEFORE EXPOSURE.  Doing it afterward will have no effect.


Just 13 mg per day of iodine prevents approximately 96 percent of radioactive iodine from binding to the thyroid gland. This is over 100x the average daily dose of iodine ingested by Americans.


I must also say that iodized salt IS NOT a good source of iodine, so please don't think that using iodized salt will help you.  It will not. While iodine is very rare in nature, there are several key foods that are very high in iodine.  The best forms of natural iodine are sea vegetables (kelp, kombu, and nori).


Sea vegetables can provide sufficient levels of iodine to help prevent radiation poisoning of your glandular system. Kelp is an abundant source of natural iodine. One quarter of a teaspoon of organic kelp granules for example, provides 3 mg of iodine (milligrams, not micrograms).  Kelp is normally used as a kind of natural salt, to add a salty taste to soups, salads or just about any meal.  It's also very high in other trace minerals.

 All seaweeds contain iodine in a natural state. One of the highest is kombu, which contains up to 2500 mcg (micrograms) per gram of kombu. You can find kombu seaweed at many local health food stores, too. Just soak it in water to reconstitute it, and then you can cook it into foods or eat it on a salad. Cooking does not destroy iodine, so don't be afraid to heat it. Iodine is a trace mineral, and no minerals are destroyed through high-heat cooking (only vitamins and enzymes are fragile to heat).

Nori sheets (the seaweed sheets used to make sushi) are also a source of iodine, although they only contain about 16 mcg per gram. They're not nearly as iodine rich as kombu, but nori is easy to find and delicious to eat.  Combining it with other sources of iodine will help ensure that you are getting enough.


Apple pectin was used after the Chernobyl nuclear reactor disaster in 1986 to reduce the load of radioactive cesium in children.  Pectin is a soluble fiber contained in the skins of apples.  It has a gel-forming effect when mixed with water, and has been proven to remove heavy metals, and even radioactive Strontium-90 from the digestive tract.


A study led by V.B. Nesterenko at the Belrad Institute of Radiation Safety was performed to see if orally administered apple pectin was effective in binding radioactive cesium-137 in the gut from food contaminated by radiation, or if eating "clean," non-contaminated food was enough. The study was a randomized, double-blind, placebo-controlled trial involving children from contaminated villages near the disaster area.

Radiation levels were measured at the beginning of the study and one month later. At the end of the trial, cesium-137 levels in children who were given apple pectin were reduced by 62%. Children who had received "clean" food and a placebo had reduced radiation levels by only 13.9%. These results proved that taking apple pectin can significantly prevent damage from radiation exposure.


Eating organic apples is a good practice, but you can also purchase apple pectin in supplement form.


 Further Prevention


Ionizing radiation creates free radicals in the body, and we all have the capacity, to a certain extent, to repair free radical damage using the using the free-radical quenching capacities that we already have in our bodies or that we can add to our bodies.  Anti-oxidants are your only defense against free radicals, so you will need to make sure you are getting adequate amounts of them.  Antioxidants exist in vegetables and fruits, so eat lots of them.  You should also supplement with green powders and fresh live juices.


To learn more about radiation and nuclear power, check out these sources: