Fukushima disaster

How safe is nuclear power? A statistical study suggests less than expected

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After the Fukushima disaster, the authors analyzed all past core-melt accidents and estimated a failure rate of 1 per 3704 reactor years. This rate indicates that more than one such accident could occur somewhere in the world within the next decade. The authors also analyzed the role that learning from past accidents can play over time. This analysis showed few or no learning effects occurring, depending on the database used. Because the International Atomic Energy Agency (IAEA) has no publicly available list of nuclear accidents, the authors used data compiled by the Guardian newspaper and the energy researcher Benjamin Sovacool. The results suggest that there are likely to be more severe nuclear accidents than have been expected and support Charles Perrow’s “normal accidents” theory that nuclear power reactors cannot be operated without major accidents. However, a more detailed analysis of nuclear accident probabilities needs more transparency from the IAEA. Public support for nuclear power cannot currently be based on full knowledge simply because important information is not available.

 

In his essay, “A skeptic’s view of nuclear energy,” Princeton University nuclear expert Harold A. Feiveson writes that he is not anti-nuclear, and he lauds improvements in the operation and reliability of nuclear power plants in recent years as “striking.” However, he notes, “Even if the chance of a severe accident were, say, one in a million per reactor year, a future nuclear capacity of 1,000 reactors worldwide would be faced with a 1 percent chance of such an accident each 10-year period – low perhaps, but not negligible considering the consequences” (Feiveson 2009, 65).
The 2011 Fukushima disaster in Japan suggested once more that severe nuclear accidents could be even more frequent than safety studies had predicted and Feiveson had hoped. So we decided to estimate the probability of a severe accident – that is, a core-melt accident – by relating the number of past core-melt accidents to the total number of years reactors have been operating (i.e. “reactor years”).
This type of prediction often runs up against the argument that nuclear operators learn from the past. Therefore we also tried to account for any learning effects in our analysis. We restricted our analysis to accidents related to civil nuclear reactors used for power generation, as arguments about trade-offs for using nuclear technology differ depending on the application. And, because the International Atomic Energy Agency (IAEA) does not distribute comprehensive, long-term reports on nuclear incidents and accidents because of confidentiality agreements with the countries it works with, we have had to use alternative sources for information on nuclear accidents over time.
By our calculations, the overall probability of a core-melt accident in the next decade, in a world with 443 reactors, is almost 70%. (Because of statistical uncertainty, however, the probability could range from about 28% to roughly 95%.) The United States, with 104 reactors, has about a 50% probability of experiencing one core-melt accident within the next 25 years.1

Measuring core melts

In 1954 the Soviet Union connected the first nuclear power reactor to the grid; Calder Hall in England followed 2 years later. The number of reactors in the world then increased steadily until the mid-1980s. From then until 2011, the number grew only from about 420 to nearly 450. A more precise calculation takes into account data from the IAEA (2006, 46–51, 81), given until 2005, assuming the number did not change significantly after 2005. Thus we estimate that there were 14,816 cumulative reactor years from 1954 until March 2011.
Since 1990, the IAEA has used a seven-level International Nuclear Event Scale (INES) to measure the severity of nuclear incidents and accidents (IAEA 2008). Two of the three reactor accidents at Fukushima rank at Level 7, as does Chernobyl. According to the IAEA treaty, “countries are strongly encouraged” to report any events “at Level 2 or above” or “events attracting international public interest” (IAEA 2009, 10). It is not possible to assign INES levels to all accidents prior to 1990.
In the literature there are slightly different definitions of a minor, major, or severe accident. We use as the indicator for a severe nuclear accident the melting of nuclear fuel within the reactor. These core-melt accidents are the ones we analyze further.
One further hurdle came from the IAEA itself. Despite its encouragement of countries to report nuclear accidents, the agency makes INES information public for only 1 year after publication. Thus while the number of reactors connected to the grid is well known (IAEA 2006, 81), information on accidents at nuclear sites is hard to get. We tried several times to acquire better data from the IAEA without success.2 As Rejane Spiegelberg Planer, a senior safety officer with the agency and an INES coordinator, informed one of the authors in an e-mail on 1 April 2011, “There is no publicly available list of events rated using INES.” We therefore collected our data from two publicly available lists of nuclear accidents, one published by the Guardiannewspaper (Rogers 2011), the other in two papers by Benjamin K. Sovacool (2008, 2010) and in his book Contesting the Future of Nuclear Power (2011). The Guardian list contains 35 incidents and accidents, whereas Sovacool lists 99 major accidents.
Both the Guardian and Sovacool lists include the same eight core-melt accidents since 1952:

  1. Windscale, England, 1957: A fire ignites plutonium piles

  2. Simi Valley, California, 1959: A partial core melt takes place at the Santa Susana Field Laboratory’s Sodium Reactor Experiment

  3. Monroe, Michigan, 1966: The sodium cooling system of a demonstration breeder reactor causes partial core melt

  4. Dumfries, Scotland, 1967: Fuel rods catch fire and cause a partial core melt

  5. Lucens, Switzerland, 1969: The coolant system of an experimental reactor malfunctions

  6. Pennsylvania, 1979: Three Mile Island

  7. Soviet Union, 1986: Chernobyl

  8. Japan, 2011: Fukushima

We excluded from our analysis the Windscale military reactor accident in 1957 and three research reactor accidents (Simi Valley in 1959, Monroe in 1966, and Lucens in 1969). Finally, we counted the damage of three reactors in Fukushima as one accident because they were triggered by the same cause, a tsunami. This leaves four accidents with core melts in civil reactors for power generation.
Using simple statistics, the probability of a core-melt accident within 1 year of reactor operation is 4 in 14,816 reactor years, or 1 in 3704 reactor years. But this simplistic analysis is subject to a large degree of uncertainty. First, it assumes the absence of any learning effect, and that reactors in all countries have the same failure probability. Second, the estimated failure probability is subject to statistical error: One can conclude with only 95% confidence that the true failure probability for a core-melt accident is between 1 in 14,300 reactor years and 1 in 1450 reactor years. Thus the best estimate is 1 in 3704 reactor years.
Having established this, we can calculate the probability of at least one core melt for a given number of calendar years. Within the next 10 years, the probability of a core-melt accident in a world with 443 reactors is 69.8%. Because of the statistical uncertainty mentioned above, this value could range from 27.8% to 95.3%. The United States, with 104 reactors, can therefore expect one accident within the next 25 years with a probability of 50.4%.

Did the reactor operators learn?

We also wanted to see whether accidents become less frequent with more operational experience. But simply analyzing the number of severe accidents against reactor years is not very illuminating because, luckily, these accidents are rather rare. So we examined the relationship between the cumulative number of all accidents, from severe to minor ones, and cumulative reactor years. The accident rate is then estimated as the ratio of cumulative number of accidents to cumulative reactor years. If the probability of an accident remained constant over time, then a graph of the above accident-rate estimates against reactor years would exhibit no trend, whereas a learning effect would result in a decreasing accident probability and the graph would exhibit a decreasing trend.
We began by plotting the data from the Guardian list, with a few exclusions.3 The graph shows a high accident rate at the beginning because of one accident in Russia in 1957. The accident rate then drops because the following years were accident-free. After around 500 reactor years, the plot appears to stabilize, varying around a constant value. This is confirmed by a detailed statistical analysis, which produces a probability for a (minor or major) accident in a nuclear power plant of about 1 in 1000 reactor years and shows no evidence of a learning effect.
An analysis of Sovacool’s more extensive data, however, promises more insight. Sovacool does not list his data according to INES levels and instead uses a different definition of a major accident: One that causes human deaths or more than $50,000 in damage, the same amount used by the US government to indicate a major accident (Sovacool 2010, 380).4 When plotted, Sovacool’s data shows an initial period with strong learning effects, followed by a remaining period with much weaker or even absent learning effect.
Using a generalized regression analysis, we further found some evidence of a fairly consistent rate of learning in the period from around 1962 to 2011, although the evidence to rule out “no learning effect” completely is weak. The data indicate a stronger learning effect in the first years of the nuclear age, but this effect is not significantly different from the later learning effect. If the initial and final learning rates did differ, then the estimated year when the learning rate changed would be 1961; but the data would also be consistent with a change year between 1957 and 1965.
Nevertheless, from 1962 to 2010 the probability of a minor or severe accident at a reactor decreased by a factor of 2.5 (from 10 accidents per 100 reactor years to 4 accidents per 100 reactor years), while the operational experience increased by a factor of 170.
Unfortunately, the most important ingredient for a reliable analysis of this kind would be comprehensive time-series data, which are filed at the IAEA but not available for the public. While we could only use Sovacool’s list with 94 events worldwide, Phillip Greenberg writes that “between 1990 and 1992 the US Nuclear Regulatory Commission received more than 6600 ‘Licensee Event Reports’ because US nuclear plants failed to operate as designed and 107 reports because of significant events (including safety system malfunctions and unplanned and immediate reactor shutdowns)” (Greenberg 1996, 130–131).
Furthermore, based on our regression analysis we calculated the expected numbers of accidents in each year and compared these with the actual numbers of accidents. The differences between these two sets of figures were consistent with what one would expect if all reactors had the same failure probability. If the reactors had different failure probabilities, then this would induce additional variation between the observed and expected numbers of accidents. Thus there is no indication that some reactors are less prone to failure than others.

Normal accidents and the need for more data

In his classic book Normal Accidents, Charles Perrow developed the theory that systems with tight coupling of, and complex interaction between, components and subsystems are inherently unsafe. He attributes nuclear power plants with the highest complexity and tightest coupling, in both aspects ranked above space missions or nuclear weapon accidents (Perrow 1999, 327). And Scott Sagan adds: “…what I will call ‘normal accident theory,’ presents a much more pessimistic prediction: Serious accidents with complex high technologies are inevitable” (Sagan 1995, 13). Statistical analysis supports this unsettling probability.
In conclusion, the number of core-melt accidents that can be expected over time in nuclear power stations is larger than previously expected. To assess the risk of similar events occurring in the future, it is necessary to determine whether nuclear power operators learn from their experiences. Our work shows that it is possible to investigate such learning effects through statistical analysis. Until the IAEA makes the relevant data available, however, the full story of accident probability and learning effects will remain untold.

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Notes

1. In the past, several studies have investigated the probability of a core melt using the probabilistic risk assessment (PRA) method. This determines probability prior to accidents by analyzing possible paths toward a severe accident, rather than using existing data to determine probability empirically. Two studies by the US Nuclear Regulatory Commission (1975, 1990) as well as a German government study (Hörtner 1980) examined seven different cases or reactors. Three calculations resulted in 1 accident in more than 200,000 reactor years, and a further three resulted in 1 accident in 11,000–25,000 reactor years. Only the result for the Zion reactor had an accident rate similar to ours, with 1 accident in 3000 years. After Chernobyl, Islam and Lindgren (1986, 691) published a short note in Nature in which, based on the known accidents (Three Mile Island and Chernobyl) and reactor years (approximately 4000) at the time, they concluded that “…the probability of having one accident every two decades is more than 95%.” Regarding PRA, they wrote: “Our view is that this method should be replaced by risk assessment using the observed data.” This sparked an intensive discussion of statistical issues in the following year (Edwards1986; Schwartz 1986; Fröhner 1987; Chow and Oliver 1987; Edwards 1987); however, there was agreement on the substantive conclusions of Islam and Lindgren.

2. An October 5 2011 e-mail by an IAEA official to one of the authors read: “Please note that old NEWS reports are not made available by the IAEA Secretariat. This is so because the reports have been provided by participating INES countries under the condition that the reports be only publicly available on NEWS for a period of 12 months (formerly 6 months). This condition has been agreed among the participating countries to prevent inappropriate use of the information (such as trying to use the information as a basis for statistical analyses and comparisons of safety performance of participating countries…”.

3. We excluded three accidents, namely Ikitelli in 1999, Yanangio in 1999, and Fleurus in 2006, because they were related to medical use. We also excluded the 1952 research reactor accident in Chalk River, Ontario. That left 16 accidents of Level 2 or higher.

4. From Sovacool’s list of 99 nuclear accidents, we excluded five: Chalk River in 1952, Windscale in 1957, Simi Valley in 1959, Monroe in 1966, and Lucens in 1969.

Japan to raise nuke safety check competency per IAEA review.

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The Nuclear Regulation Authority announced the plans Monday in response to an IAEA evaluation of Japan’s nuclear safety regulations since the 2011 Fukushima disaster.

Japan Fukushima, Japan nuclear safety check, Japan IAEA, Japan Nuke safety, Fukushima nuclear plantFILE – In this June 27, 2013 file photo, a freighter, left in foreground, carrying MOX, a mixture of uranium and plutonium oxide, arrives at the Takahama nuclear power station in Takahama town in Fukui prefecture, northwestern Japan, when the power plant received the first shipment of reprocessed nuclear reactor fuel from France since the 2011 Fukushima disaster that forced it to shut down reactors, hoping to use the fuel once they get the go-ahead to restart their reactors. (AP Photo)

Japanese nuclear regulators said they will revise laws, nearly double inspection staff and send some inspectors to the U.S. for training to address deficiencies cited by the International Atomic Energy Agency.

The Nuclear Regulation Authority announced the plans Monday in response to an IAEA evaluation of Japan’s nuclear safety regulations since the 2011 Fukushima disaster. The report was submitted to the government last week.

 The IAEA review, its first since the Japanese nuclear authority’s establishment in 2012, was conducted in January to determine whether the country’s new regulatory system meets international standards. The IAEA report said even though Japan has adopted stricter safety requirements for plant operators, inspections are reactive, inflexible and lack free access. The report noted that the nuclear authority has made efforts to increase its transparency and independence.
The authority’s commissioners met Monday and decided to give inspectors greater discretion and free access to data, equipment and facilities. Current on-site checks have largely become a choreographed routine. Inspectors’ requests for access to data and equipment outside of regular quarterly inspections are not mandatory, and there is no penalty for plant operators that fail to meet safety requirements. Inspections also tend to be limited to a checklist of minimum requirements. The IAEA report came as nuclear safety concerns increased among the Japanese public following two powerful deadly earthquakes in southern Japan. Three reactors at the Fukushima Dai-ichi nuclear power plant suffered meltdowns in March 2011 following a massive earthquake and tsunami. A series of investigations have blamed safety complacency, inadequate crisis management skills, a failure to keep up with international safety standards, and collusion between regulators and the nuclear industry as the main contributing causes of the disaster. The authority plans to revise laws next year and enact them in 2020 to implement the IAEA’s recommendations, officials said Monday.
The authority also said it would increase the size and competency of its staff. The IAEA urged Japan to develop training programs and step up safety research and cooperation with organizations inside and outside the country. Japan plans to send five inspectors to the U.S. Nuclear Regulatory Commission later this year for training in nuclear safety inspections. The trainees will be sent to NRC regional offices and its technical training center in Tennessee, according to Shuichi Kaneko, an authority official. “We look to the U.S. as a model,” he said. “We are finally beginning to catch up, though a framework is not there yet.” While the 1,000 U.S. inspectors are given two years of training, Japan has only 150 staffers who receive just a two-week basic course, Kaneko said. He said on-site inspections at each plant in the U.S. average 2,000 hours a year, and only 168 hours in Japan.
The authority plans to start hiring more staff next spring and eventually increase its staff by at least 100 to adapt to increased inspection needs, Kaneko said. Theoretically, to match U.S. safety inspection levels, Japan would need at least 250 inspectors. Japan largely ignored an IAEA review in 2007 that concluded that its inspection system was inadequate.

Data proves Fukushima has exceeded Chernobyl in radiation release.

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The cumulative amount of radiation released from Fukushima already exceeds that of the infamous 1986 Chernobyl disaster, says a new study published in the journal Nature — and the damage, of course, is still ongoing.

Chernobyl

Scientists from Japan, after testing radiation concentrations in various spots throughout the Pacific Ocean and on land, found that at least 120 petabecquerels (PBq), or 120 quadrillion becquerels (Bq), of radioactive cesium-134 (Cs-134) and cesium-137 (Cs-137) have been released by Fukushima just into the world’s oceans.

This figure is 11 percent higher than the total amount of radioactive cesium released by Chernobyl on both land and water, illustrating the true severity of the Fukushima disaster that the mainstream media is concealing from the public.

According to the study, researchers analyzed data collected at numerous measuring stations located throughout the North Pacific Ocean and elsewhere where Fukushima radiation was released. Though incomplete, this data was used to come up with radiation release estimates that account for the spread of contaminated water via ocean currents.

Based on these models, it was determined that up to 46 PBq of Cs-134 was released into the North Pacific Ocean following Fukushima. However, the study also says that the 6 PBq of Cs-134 definitively identified in the study area may represent as little as 10 percent of the overall release, bumping this figure to 60 PBq of Cs-134.

Combined with the total estimated release of Cs-137, the study authors concluded that up to 120 PBq of both types of radioactive cesium were released just into the North Pacific Ocean following the Fukushima disaster. Compared to the 108 PBq of radioactive cesium released during Chernobyl, this represents an 11 percent greater amount.

Fukushima: hands-down the worst nuclear disaster in history

But it is important to note here that the 108 PBq figure for Chernobyl includes radiation deposited on both land and sea. In the case of Fukushima, the 120 PBq figure only accounts for radiation released into water, and specifically water circulating in the North Pacific Ocean — the total amount of Fukushima radiation released on both land and sea is likely orders of magnitude higher than this figure.

“A report by the Nuclear [Energy] Agency states that when more detailed deposition data eventually became available, the United Nations estimated the total Chernobyl release of 137CS at 70 PBq,” explains ENENews.com.

“134Cs is estimated to have been 53.7% of the 137Cs — approximately 38 PBq of 134Cs — resulting in a total of 108 PBq. Unlike the Fukushima total… this does include all 134Cs and 137Cs releases from Chernobyl — not just what was deposited in the ocean.”

The implications of this are astounding, as Chernobyl has long been regarded as one of the worst nuclear disasters in history. The exclusion zone surrounding Chernobyl is still mostly deserted, having displaced hundreds of thousands of people, and readings still show high levels of radiation near the plant.

And yet the Chernobyl disaster clearly pales in comparison to Fukushima. Not only is Fukushima far more of a threat to humanity due to its direct proximity to the ocean, but the most credible data we have shows that, in the aftermath, Fukushima is spreading far more radiation across the globe than Chernobyl ever could.

Even worse is the fact that the 120 PBq figure does not take into account all the other radioactive isotopes like strontium, plutonium and uranium that have been spreading through the air and water since 2011 when the disaster occurred. Taking all these other contaminants into account paints an even more dire picture of what the world has to look forward to.

Sources:

http://www.nature.com

http://enenews.com

http://triblive.com

Learn more: http://www.naturalnews.com/047053_Fukushima_Chernobyl_radiation.html#ixzz3EoIeU9Gl

8 Shocking Health Effects from the Fukushima Disaster .

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It’s been a couple years since the Fukushima disaster but the ruins are still smoldering and the negative health consequences are more pronounced than ever. The somewhat indifferent response from many governmental health agencies around the world to the Fukushima disaster was perhaps more shocking than the disaster itself. Authorities around the globe assured us not to worry, claiming any radiation that had come into contact with citizens was well below the detectable and harmful level. The message is clear, everyday citizens can longer rely on their government for protection.

fukushima

As tons of radioactive water continues to spill into the Pacific Ocean, many national health agencies have raised the standards for acceptable radiation exposure to reinforce their absurd statements. The previous standards for 30 years of radiation exposure would have generated a cancer rate of 1 in 10,000. Now that radiation standards have been raised (thanks to the Obama Administration’s green-lit effort to increase radiation exposure to 2,000 millirems), the cancer rate from 30 years of exposure is now at 1 in 23! [1]

What other problems have sprung up since the nuclear disaster in Fukushima?

 

   

1. Skin Contamination

Skin contamination remains one of the greatest risks following a radiological disaster like Fukushima. The availability of radiological decontamination agents remained in limited supply immediately following the disaster, and many of these agents require fresh water. Unfortunately, access to clean water can be very difficult in areas near Fukushima due to the high levels of radiation.[2] Skin exposure to chemicals and radiation may result in superficial skin issues and endocrine damage. [3]

2. Psychological Trauma

Data indicates that workers and mothers of young children have the greatest risk of PTSD, depression, and anxiety following a radiological event. These effects may be a direct result from exposure to radiation, and radiation itself may be directly linked to mood disorders. Also, parents may fear for their family’s well being during and after a nuclear disaster, further increasing the chances of becoming psychologically and emotionally unstable.[4] Children and adolescents may also experience long-term psychological difficulties with unknown consequences. [5]

3. Cancer

Scientists and governmental health agencies have been highly aware of radiation’s impact on cancer risk in humans and animals. High doses can be fatal and increase the chances of inheritable genetic defects.[6]

4. Thyroid Damage

Iodine 131, a radioisotope of iodine found in nuclear fission, quickly accumulates in the thyroid and replaces stable, beneficial iodine. It disrupts normal thyroid function to negatively impact hormones, body weight, and energy levels. This iodine isotope can cause thyroid cancer and hypothyroidism. [7] Nuclear disasters, specifically those in Chernobyl, Hiroshima, and Fukushima, have resulted in a significant increase in thyroid cancers.[8]

5. Women are More at Risk

Research conducted in the area around Fukushima explored the impact radiation had on men and women and how the genders compared when it came to health risk severity. Women proved more sensitive to the effects of radiation, with pregnant women displaying an even higher level of susceptibility. [9]

6. Pregnancy Issues

Pregnant women are at a higher risk for developing issues related to iodine deficiency when exposed to iodine 131, an issue that can slow thyroid and hormone function. Iodine deficiency in pregnant women can cause miscarriage, stillbirths, and other complications.[10] As the years continue to pass following the Fukushima disaster, Japanese officials still claim ignorance of the possible effects radiation has on pregnant women and their unborn children.

7. Thyroid Disorders and Newborns

Despite the multitude of health effects to the developing fetus, research has uncovered severe issues with radiation on the thyroid gland in newborn infants. From March to June of 2011, thyroid problems soared 28% in babies born along the Pacific Rim. States along this area include Hawaii, California, Oregon, Washington, and Alaska. A 2013 study published in Open Journal of Pediatrics noted significantly higher incidences of hypothyroidism in these states. [11]

8. Thyroid Cancer in Children

During a radiological event, protecting the health of children (the most susceptible population group) becomes a foremost issue. [12] To date, 44 Japanese children under the age of 18 living near Fukushima’s nuclear plant at the time of the disaster have developed thyroid cancer, a significant increase compared to cancer incidences prior to the event.

What Can Be Done During a Nuclear Event?

Any type of nuclear emergency requires immediate action in an effort to protect citizens. Government authorities will typically administer high doses of potassium iodide to those affected in an effort to block thyroid absorption of iodine 131. [13] While this traditional protocol may help, the results show the need for better, more effective protective options.

When it comes to protecting yourself and your family, you ultimately have to rely on your own efforts rather than those exercised from official members of the government. Although potassium iodide has been traditionally used to block the absorption of iodine 131 in the thyroid, it is not the most efficient form of iodine for the human body. Nascent iodine offers a more bioavailable option with a higher rate of absorption. Detoxification may also be helpful for removing impurities and toxic metals that may accumulate during a nuclear event.

What are your favorite ways to protect yourself from overseas radiation? Let us know in the comments!

-Dr. Edward F. Group III, DC, ND, DACBN, DCBCN, DABFM

Article References:

  1. Global Research News. Civilian Cancer Deaths Expected to Skyrocket Following Radiological Incidents.Public Employees for Environmental Responsibility (PEER).
  2. Tazrart A, Bérard P, Leiterer A, Ménétrier F. Decontamination of radionuclides from skin: an overview. Health Phys. 2013 Aug;105(2):201-7. doi: 10.1097/HP.0b013e318290c5a9.
  3. Asfandyar Khan Niazi and Shaharyar Khan Niazi. Endocrine effects of Fukushima: Radiation-induced endocrinopathy. Indian Journal of Endocrinology and Metabolism. 2011 April-June; 15(2): 91-95.
  4. Bromet EJ. Emotional consequences of nuclear power plant disasters. Health Phys. 2014 Feb;106(2):206-10. doi: 10.1097/HP.0000000000000012.
  5. Hayashi K, Tomita N. Lessons learned from the Great East Japan Earthquake: impact on child and adolescent health. Asia Pac J Public Health. 2012 Jul;24(4):681-8. doi: 10.1177/1010539512453255.
  6. Boice JD Jr. Radiation epidemiology: a perspective on Fukushima. J Radiol Prot. 2012 Mar;32(1):N33-40. doi: 10.1088/0952-4746/32/1/N33.
  7. Spallek L, Krille L, Reiners C, Schneider R, Yamashita S, Zeeb H. Adverse effects of iodine thyroid blocking: a systematic review. Radiat Prot Dosimetry. 2012 Jul;150(3):267-77. doi: 10.1093/rpd/ncr400.
  8. Dilas LT, Bajkin I, Icin T, Paro JN, Zavisi BK. Iodine and thyroid gland with or without nuclear catastrophe. Med Pregl. 2012 Nov-Dec;65(11-12):489-95.
  9. Evangeliou N1, Balkanski Y2, Cozic A2, Møller AP3. Global and local cancer risks after the Fukushima Nuclear Power Plant accident as seen from Chernobyl: A modeling study for radiocaesium (134Cs &137Cs). Environ Int. 2013 Dec 19;64C:17-27. doi: 10.1016/j.envint.2013.11.020.
  10. http://www.ncbi.nlm.nih.gov/pubmed/22742605
  11. Joseph J. Mangano, Janette D. Sherman. Elevated airborne beta levels in Pacific/West Coast US States and trends in hypothyroidism among newborns after the Fukushima nuclear meltdown.Open Journal of Pediatrics, 2013, 3, 1-9 OJPed.
  12. Fushiki S. Radiation hazards in children – lessons from Chernobyl, Three Mile Island and Fukushima. Brain Dev. 2013 Mar;35(3):220-7. doi: 10.1016/j.braindev.2012.09.004.
  13. Reiners C, Schneider R. Potassium iodide (KI) to block the thyroid from exposure to I-131: current questions and answers to be discussed. Radiat Environ Biophys. 2013 May;52(2):189-93. doi: 10.1007/s00411-013-0462-0.

Article References:

1. Dr Philippe Grandjean MD, Philip J Landrigan MD. Neurobehavioural effects of developmental toxicity. The Lancet Neurology, Volume 13, Issue 3, Pages 330 – 338, March 2014. doi:10.1016/S1474-4422(13)70278-3.

Radiation level in tuna off Oregon coast tripled after Fukushima disaster

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While the state of Oregon gears up to test its shores for radioactive contamination from Japan’s Fukushima nuclear disaster, university scientists have found that radiation levels in some albacore tuna caught off its coast have tripled.

According to researchers at the University of Oregon, the results came after tests analyzed the cesium levels in 26 tuna caught prior to the 2011 nuclear calamity – as far back as 2008 – and those caught after the accident.

AFP Photo / Yoshikazu Tsuno

Although the levels of radioactive isotopes in some of the tuna tripled after the disaster, the researchers found they are still “a thousand times lower” than the safety standards outlined by the US Department of Agriculture.

“A year of eating albacore with these cesium traces is about the same dose of radiation as you get from spending 23 seconds in a stuffy basement from radon gas,” the study’s lead author, Delvan Neville said to Oregon’s Statesman Journal.

Still, Neville added that the discovery of any amount of radiation is significant.

“You can’t say there is absolutely zero risk because any radiation is assumed to carry at least some small risk,” he said. “But these trace levels are too small to be a realistic concern.”

Researchers stated that the migration paths of the tuna could also affect the levels of radiation going forward. Most of the 3-year-old tuna tested had no traces of Fukushima radiation, but 4-year-old tuna – which likely traveled through the radioactive plume a couple of times – had higher cesium levels. Continued migration could increase cesium levels further, but the researchers said it would still fall well below maximum safety levels.

Since the results did reveal a spike in radiation, though, the researchers will be expanding their study beyond Oregon to test a larger number of tuna across the West Coast.

“The presence of these radioactive isotopes is actually helping us in an odd way – giving us information that will allow us to estimate how albacore tuna migrate between our West Coast and Japan,” Neville told the Journal.

Meanwhile, Oregon state itself plans to hold its next quarterly radiation test on May 13. Back in February, Ken Buesseler of the Woods Hole Oceanographic Institution stated that a plume of radioactive water from Fukushima would likely hit the US West Coast by April 2014. Buesseler said the plume is likely too diluted to pose a health concern to Americans or the habitat, but added that only testing will be able to confirm his belief.