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Radioactive Iodine 129 & 131

Published on May 26, 2017

In the 1990s, many studies reported an increase in thyroid cancer in children due to the release of Iodine-131 during the Chernobyl accident in 1986 (Prisyazhniuk et al., 1991; Kazakov et al., 1992). While a vast array of radioactive isotopes were released into the environment during the Fukushima meltdown, Iodine-129 is a particularly concerning material, due to its incredibly long half-life.

We have all been led to believe that radioactive iodine is no longer a threat from Fukushima because it has such a short half-life. However just another proof of a vast cover-up and diminishing of concern over the threat from Fukushima comes from I-129, which has a long half-life of ~15.7 million years.

Thanks to that, the Pacific coast will never be the same. It will take about 16 million years for the contamination from the nuclear accident to dissipate. Radiation apologists diminish the dangers of radioactive iodine because they focus only on Iodine 131, which has a short half-life of eight days.

The release of iodine-129 into the environment means that food that comes from the North American western coast will likely be contaminated with radiation for innumerable generations to come. Radiation in the oceans will inevitably enter our water supply, and consequently our food supply as well.

According to the Agency for Toxic Substances and Disease Registry (ATSDR), iodine from the ocean enters the air as sea spray or iodine gas. Once in the air, iodine can then combine with water particles and enter surface water and soil once the particles fall to ground. Iodine can remain in the soil for extremely long periods of time, because it can combine with organic material easily. Plants and vegetation that grow in this soil also have the potential to absorb the iodine.

Dr. Michael Friedman says, “Women are particularly at risk due to environmental agents depleting iodine reserves and other agents exposing them to radioactive 1-131. After the thyroid gland, the distal portions of the human mammary glands are the heaviest users/concentrators of iodine in tissue. Iodine is readily incorporated into the tissues surrounding the mammary nipples and is essential for the maintenance of healthy functioning breast tissue. The radioactive decay of 1-131 in breast tissue may be a significant factor in the initiation and progression of both breast cancer and some types of breast nodules.”

Radioactive iodine is one of the most harmful radionuclides because it has the highest activity among radionuclides immediately after an accident and it causes thyroid cancer in children.

Iodine -129 – A Growing Radiological Risk

Iodine 131 and Iodine 129 travel together, so the presence of the easily detectable short-lived isotope signals the presence of the longer-lived one. “If you have a recent event like Fukushima, you are going to have both present. The iodine-131 is going to decay away pretty quickly over the course of weeks, but the iodine-129 is there forever, essentially,” Joshua Landis, a research associate in the Department of Earth Science at Dartmouth explains, “Once the iodine-131 decays, you lose your ability to track the migration of either isotope.”

One of the many problems with the official government maps and press releases is that they do not mention radioactive Iodine 129. Not only is this long lived radioactive Iodine 129 dangerous to thyroids, just like it’s short lived cousin, it also gets poured out of melting down reactors at a rate that is about 31 times that of the short lived radioactive cousin, Iodine 131. The nuclear industry propaganda machine likes to focus only on the short-lived Iodine and ignore the long-lived one, which has serious implications for the future of the human race.

Amazing facts when you consider that 31.6 times as much iodine-129 than iodine-131was released in the early days of the Fukushima catastrophe[1] and that was felt as far away as New York where Iodine -131gas exceeded 3,400 μBq/m³.[2]

Iodine-129, although a result of nuclear fission in reactors, also occurs to a small extent in the upper atmosphere due to the interaction of high-energy particles with naturally-occurring xenon.

“This is very amazing to me, having been working in the radioactive xenon monitoring field for about 17 years now. This was astounding to me… You can see background levels around 0.1 mBq/m3… Note the peak concentration we saw was in the range of 45,000 mBq/m3 — so that is 450,000 times our background level. For me that’s astounding. We never have ever seen anything even close to that. So the concentrations went up and up and up every day, and so that was quite amazing to see this 7,000 kilometers away from the event. I only show some of the data here, but it actually persisted for weeks at very measurable levels, and filled the entire northern hemisphere and mixed into the southern hemisphere,” reports one of the researchers on ENE news.

Iodine 129 decays into radioactive Xenon 129 sometime during its 16 million years. It is important to realize that radioactive Iodine does not disappear. It transmutes as it decays into other radioactive elements, such as radioactive Xenon gas, which can be inhaled easily, and which causes lung cancer.

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Once inhaled, Xenon gas decays into solid radioactive Cesium, which is also cancer causing, but in different ways. Then radioactive cesium decays over the next 300 years into other more dangerous, radioactive elements, finally ending with the toxic heavy metal lead, which is extremely toxic and deadly even in small amounts.

Some types of radioactive xenon is produced from nuclear fission. Other isotopes of xenon are produced by beta decay meaning heightened world levels of xenon are a symptom of numerous other types of radioactive particles decaying in the broad environment. 131mXe, 133Xe, 133mXe, and 135Xe e some of the fission products of both 235U and 239Pu

According to the Environmental Protection Agency when I-129 or I-131 is ingested, some of it concentrates in the thyroid gland. The rest passes from the body in urine. Airborne I-129 and I-131 can be inhaled. In the lung, radioactive iodine is absorbed, passes into the blood stream, and collects in the thyroid.

In the body, iodine has a biological half-life of about 100 days for the body as a whole. It has different biological half-lives for various organs: thyroid – 100 days, bone – 14 days, and kidney, spleen, and reproductive organs – 7 days.

Iodine 129 and 131 experience beta decay, which means they emit beta particles when decaying from unstable to stable form. Beta particles are moderately energetic. Gamma rays are also emitted and are highly energetic, which means that they can be detected outside the body. Beta particles easily pass through soft tissue and cause damage to DNA by shattering DNA strands and knocking out chunks of gene sequences.

“Due to its long half-life and continued release from ongoing nuclear energy production, Iodine-129 is perpetually accumulating in the environment and poses a growing radiological risk,” the authors of a study at Dartmouth point out.

It is important to note that I-129 was already present before the Fukushima Daiichi accident owing to atmospheric nuclear testing held in the 1950s and 1960s, and later, discharge from spent-nuclear-fuel reprocessing plants.

Iodine-129 has leaked into groundwater at nuclear weapons production locations, including the Hanford Site in Washington State. Meanwhile, France and England — which produce large proportions of their electricity via nuclear power — are reprocessing spent fuel and disposing of vast quantities of iodine-129 simply by dumping it in the ocean.

Ocean disposal of iodine-129 appears to have resulted in massive increases of radionuclide concentrations. Currents carry the British and French iodine-129 northward, and a 2003 Danish study found concentrations in the Kattegat strait between Denmark and Sweden increased six fold between 1992 and 2000. Concentrations of iodine-129 in some Arctic waters are 4,000 times their pre-nuclear era levels.

The Fukushima Daiichi nuclear power plant released an enormous amount of liquid waste of Iodine 129 and other fission isotopes directly into the Pacific Ocean that were and continue to be dispersed eastwards.

Treatment and Prevention of Radiation Poisoning from Radioactive Iodine

It is important to remember that Iodine supplementation diminishes the dangers of ionized radiation. Dr. Brownstein writes, “If there is enough inorganic, non-radioactive iodine in our bodies, the radioactive fallout has nowhere to bind in our bodies. It will pass through us, leaving our bodies unharmed. It is important to ensure that we have adequate iodine levels before fallout hits.” See my essay summarizing all the reasons to supplement with iodine and my important essay on iodine dosages.

[1] Geochemical Journal, Vol. 46, pp. 327 to 333, 2012


Hi, I'm Dr. Mark Sircus, AC., OMD, DM (P), a doctor and writer of more than 23 books that have sold over 80,000 copies all over the world. I've been promoting Iodine as a safe and effective medicine for more than 10 years and my book "Iodine - Bringing Back the Universal Medicine" has been repeatedly praised by other iodine experts like Dr David Brownstein.

On my website there are hundreds of free articles, but if you need some personalized help, you can make a consultation.

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