High start-up costs: Huge investments are needed for thorium nuclear power reactor, as it requires significant amount of testing, analysis and licensing work. Also, there is uncertainty over returns on the investments in these reactors. For utilities, this factor can weigh on the decisions to go ahead with plans to deploy the reactors. The reactors also involve high fuel fabrication and reprocessing costs.
High melting point of thorium oxide: As melting point of thorium oxide is much higher compared to that of uranium oxide, high temperatures are needed to make high density ThO2 and ThO2–based mixed oxide fuels. The fuel in nuclear fission reactors is usually based on the metal oxide.
Times 12th May 2018 Uranium is mined and then processed as nuclear fuel for military or civilian purposes. The ore is ground up and chemically treated to yield “yellowcake”, a coarse powder of uranium oxide. Converted into purified fuel rods, it can be used in pressurised heavy water reactors.
For other uses, the uranium oxide is converted into uranium hexafluoride gas so that it can be enriched. The enrichment process increases the percentage of a particular isotope, uranium-235, which makes up 0.7 per cent of natural uranium. The rest is uranium-238. The commonest method of enrichment is isotope separation by gas centrifuge. Centrifuges rotate at high speed, separating the isotopes by weight and sending the heavier uranium-238 to the outside of the cylinder while the lighter 235 collects at the centre.
The slightly enriched stream is extracted and fed into the next centrifuge, where the process is repeated, enriching it further. Most nuclear power reactors use uranium that has been enriched to a composition of between 3 and 5 per cent uranium-235. Anything up to 20 per cent uranium-235 is called low-enriched uranium. Uranium enriched to between 12 and 19.75 per cent is used in the production of medical isotopes in research reactors.
Uranium enriched above 20 per cent is called highly enriched uranium, while 20 per cent is the lowest theoretical threshold for weapons-grade uranium. Most weapons use uranium that is 90 per cent enriched. The first stages
require more centrifuges due to the volume of uranium. The process gets easier as purity increases, making the leap from low to high-enrichment easier than the leap from natural uranium to low-enriched. Once the 20 per cent threshold is breached, weapons grade is within reach. https://www.thetimes.co.uk/edition/world/iran-saudi-arabia-uranium-from-ore-to-weapons-grade-mf0jdqr86
The Monju fast-breeder reactor experiment yielded few sufficient results despite an investment of at least ¥1.13 trillion ($10.3 billion) worth of taxpayers money since 1994, state auditors confirmed on Friday.
The trouble-plagued prototype, which only ran for 250 days, was designed to play a key role in Japan’s quest to set up a nuclear fuel recycling program, but the project only achieved 16 percent of the intended results, the Board of Audit said.
The government finally decided to scrap Monju in December 2016 at an estimated additional cost of ¥375 billion. But the audit board noted that the 30-year decommissioning plan could cost even more.
The reactor, which started operations in 1994, was designed to produce more plutonium than it consumes while generating electricity, experienced several problems over its more than two-decade run, including a sodium coolant leak and attempted cover-up, and equipment inspection failures.
“Flawed maintenance led to the decommissioning,” the auditors concluded in their report.
But the report also spotlights the absence of a systematic evaluation system for the project. During the entire experiment, the auditors expressed their opinions on Monju’s research and development costs only once — in 2011.
Monju was only up and running for 250 days in total after repeatedly failing to complete test items, according to the report.
As for the decommissioning costs, the report said they might expand because the current estimate does not include personnel costs and taxes. It also noted that the cost of removing the radioactive sodium coolant could change.
The world’s nuclear energy watchdogs: 4 questions answered, The Conversation, Scott L. Montgomery Lecturer, Jackson School of International Studies, University of Washington, May 4, 2018
North Korea has promised to get rid of its nuclear weapons, but how will the world know if it actually follows through?
There is only one international agency in the world that could verify their compliance, the International Atomic Energy Agency. However, North Korea canceled its membership to the organization in 1994. When the IAEA demanded to inspect certain facilities in North Korea, they backed out and eventually expelled all nuclear inspectors in 2009.
Since then, North Korea has remained outside the IAEA’s jurisdiction. While it isn’t clear whether the agency will be called upon if a deal on denuclearization is reached, IAEA Director General Yukiya Amano has said the agency is prepared to send a team of inspectors should a diplomatic agreement be reached.
So, with that possibility in mind, let’s look at how the agency operates and all the other nuclear energy challenges it faces beyond North Korea.
1. What is the International Atomic Energy Agency?
The IAEA was founded in 1957, inspired by U.S. President Eisenhower’s “Atoms for Peace” speech promoting the peaceful uses of nuclear energy. From the beginning, its task has been to spread and monitor the application of nuclear technology for non-military uses and make sure that such technology is not diverted to build weapons.
…..Headquartered in Vienna, Austria, the agency is a membership organization that reports annually to the United Nations, but is independent of it. Member nations must obey its rules and requirements in order to receive the knowledge and technology it provides.
The agency is best known for its work in two areas. The first is nuclear safety: protecting people and the environment from harmful radiation. The second is nuclear security, which focuses on preventing the spread of nuclear weapons, including threats of nuclear terrorism.
This watchdog role requires determining whether any member country might be developing nuclear weapons – specifically nations that have signed international treaties. For example, the Treaty on the Non-Proliferation of Nuclear Weapons is the world’s most important legally binding agreement for preventing the spread of nuclear weapons. At present, a total of 191 states have joined the treaty. Three nuclear weapons states – Israel, India and Pakistan – have not signed and North Korea withdrew from it in 2003.
The IAEA evaluates compliance with other treaties including those governing nuclear free zones and important safeguard agreements with as many as 181 nations……..
3. How does the agency verify how nuclear material is being used?
Among the more than 2,500 people who staff the IAEA, only about 385 are inspectors. They come from 80 nations and mainly hold backgrounds in physics, chemistry and engineering.
Routine inspections involve verifying whether a member’s report about its nuclear facilities and material is accurate. Depending on the size of the facility, this might take a few hours for one or two people or two weeks for 10 inspectors. They do this in a number of ways, including the collecting of samples of nuclear material, measuring levels of radioactivity, checking plans and blueprints against actual construction, and interviewing officials, engineers and others involved in nuclear work.
Over time, the agency has had to make changes in its inspection processes. For example, before 1997, inspectors were limited to examining only facilities that member states had declared. After discovering that Iraq had lied about the true extent of its nuclear program, the IAEA board of governors approved a protocol to allow inspectors to access undeclared sites that might be involved in nuclear work.
Inspectors have also found themselves in the line of political fire. For example, between 2002 and 2003, the Bush administration wanted evidence that Iraqi President Saddam Hussein had an active nuclear weapons program. U.S. attempts to pressure the agency did not alter IAEA findings that such evidence could not be found.
Similarly, the agency has stood its ground in favor of the Iran nuclear deal and Iran’s compliance in the face of President Trump’s continued criticism of the agreement.
4. What are the main challenges facing the agency?
There are myriad challenges facing the IAEA.
Expanding demands on the agency have come from developing nations with growing economies such as Thailand and Chile that want to use nuclear science in medicine, agriculture and industry. Growth of nuclear power into new areas of the world is bringing concern about the development of weapons and terrorist groups acquiring nuclear material.
North Korea, whose weapons program may or may not be halted by talks with the U.S., has plutonium and uranium that could be sold without international approval or safeguards.
Then there is the Trump administration’s threat to abandon the Iran nuclear deal, a move that would dismiss years of effort by the IAEA to head off an arms race in the region. At the same time, any future need to verify that Iran is not building a weapon would almost certainly rely on IAEA inspectors. Similarly, it seems likely that a deal between the U.S. and North Korea would require the Democratic People’s Republic of Korea to rejoin the agency and have any denuclearization efforts confirmed by it as well.
the US has lost at least six atomic bombs or weapons-grade nuclear material since the Cold War.
Not only that, but the US is responsible for at least 32 documented instances of a nuclear weapons accident, known as a “Broken Arrow” in military lingo. These atomic-grade mishaps can involve an accidental launching or detonation, theft, or loss – yep loss – of a nuclear weapon.
February 13, 1950
The first of these unlikely instances occurred in 1950, less than five years after the first atomic bomb was detonated. In a mock nuclear strike against the Soviet Union, a US B-36 bomber en route from Alaska to Texas began to experience engine trouble. An icy landing and stuttering engine meant the landing was going to be near-impossible, so the crew jettisoned the plane’s Mark 4 nuclear bomb over the Pacific. The crew witnessed a flash, a bang, and a sound wave.
The military claim the mock-up bomb was filled with “just” uranium and TNT but no plutonium, so it wasn’t capable of a nuclear explosion. Nevertheless, the uranium has never been recovered.
March 10, 1956
On March 10, a Boeing B-47 Stratojet set off from MacDill Air Force Base Florida for a non-stop flight to Morocco with “two nuclear capsules” onboard. The jet was scheduled for its second mid-flight refueling over the Mediterranean Sea, but it never made contact. No trace of the jet or the nuclear material was ever found again.
February 5, 1958
In the early hours of February 5, 1958, a B-47 bomber with a 3,400-kilogram (7,500-pound) Mark 15 nuclear bomb on board accidentally collided with an F-86 aircraft during a simulated combat mission. The battered and bruised bomber attempted to land numerous times, but to no avail. Eventually, they made the decision to jettison the bomb into the mouth of the Savannah River near Savannah, Georgia, to make the landing possible. Luckily for them, the plane successfully landed and the bomb did not detonate. However, it has remained “irretrievably lost” to this day.
January 24, 1961
On January 24, 1961, the wing of a B-52 bomber split apart while on an alert mission above Goldsboro, North Carolina. Onboard were two 24-megaton nuclear bombs. One of these successfully deployed its emergency parachute, while the other fell and crashed to the ground. It’s believed the unexploded bomb smashed into farmland around the town, but it has never been recovered. In 2012, North Carolina put up a sign near the supposed crash site to commemorate the incident.
December 5, 1965
An A-4E Skyhawk aircraft loaded with a nuclear weapon rolled off the back off an aircraft carrier, USS Ticonderoga, stationed in the Philippine Sea near Japan. The plane, pilot, and nuclear bomb have never been found.
In 1989, the US eventually admitted their bomb was still laying in the seabed around 128 kilometers (80 miles) from a small Japanese island. Needless to say, the Japanese government and environmental groups were pretty pissed about it.
?, 1968
At some point during the Spring of 1968, the US military lost some kind of nuclear weapon. The Pentagon still keeps information about the incident tightly under wraps. However, some have speculated that the incident refers to the nuclear-powered Scorpion submarine. In May 1968, the attack submarine went missing along with its 99-strong crew in the Atlantic Ocean after being sent on a secret mission to spy on the Soviet navy. This, however, remains conjecture.
How the Manhattan Project’s Nuclear Suburb Stayed Secret, Oak Ridge, Tennessee, once home to 75,000, went up fast and under the radar. But it was built to last, too. Atlas Obscura , BY JESSICA LEIGH HESTER , MAY 03, 2018 “…… Oak Ridge isn’t like most of the country’s other suburbs. The town was conceived and built by the United States government in the early 1940s as base for uranium and plutonium work, as part of the Manhattan Project. As the nuclear effort marched along, the town grew, too. By 1945, a dense suburb had taken shape, home to roughly 75,000 people. At war’s end, Oak Ridge was the fifth-largest city in the state—and all along, it was supposed to be a secret.
…….. the pace of building there was stunning enough, but doing it all under the radar required a little willful blindness. The town didn’t appear on any official maps, and visitors were screened by guards posted at the entrances. Still, at that scale, it couldn’t be truly clandestine. “People saw stuff, certainly,” Moeller says, but probably chose not to wonder too deeply about what was happening there out of a combination of patriotism and ignorance. Moeller speculates that those who saw workers and supplies streaming into the site may have sensed that asking too many questions would have been un-American. The idea was, “it’s not my business; it’s for the war effort,” he says. “There was a much greater spirit of national unity than we could even fathom now.”
Billboards were installed all over town to remind workers to keep their mouths shut about their work, even though most workers knew very little about the project’s true scope.
Similar “secret cities” were built in other parts of the country, such as Los Alamos, New Mexico, and Hanford, Washington, home to 125,000. Designers of these towns had additional tactics to obscure specifics. In Los Alamos and Hanford, sometimes everyone was given the same mailing address. At Oak Ridge, street addresses were designed to be confusing to outsiders. Bus routes might be called X-10 or K-25 or Y-12, in reference to the factories they led to, while dorms had simple names such as M1, M2, and M3. If you didn’t already know where you were trying to go, none of it would make sense. “There weren’t any signs on buildings, just numbers, codes names, and numbers,” Wilcox recalled. The town was full of such ciphers, and even employees didn’t know how to decode them all. ……https://www.atlasobscura.com/articles/how-to-build-secret-nuclear-city
Welcome to Israeli Nuclear Weapons 101 The National Interest, Daniel R. DePetris, September 20, 2015
1.The Number is in Doubt:
While everyone believes that the Israelis possess a sizable nuclear arsenal, no one really knows how big that arsenal is. In 2008, President Jimmy Carterestimated that Israel probably had a minimum of 150 weapons in stock ready to use if the most dire circumstances warrant. Six years later, the former President revised that estimate and put the figure in the 300 range, which—based on Carter’s calculations—would mean that Israel doubled its arsenal from the 2008-2014 time-period. Iranian foreign minister Mohammad JavadZarif told reporters at the United Nations at the height of the P5+1-Iran nuclear talks that Israel is “sitting on 400 nuclear warheads.” The Bulletin of Atomic Scientists believes Zarif’s figure is far too large and unrealistic given the fact that Israel’s weapons are designed for deterrence purposes rather than actual hire-trigger use. A better figure, the board writes, is “sixty-five to eighty-five warheads” as cited in a Rand Corporation study.
To put it bluntly, the world doesn’t have a clue about how many nukes Israel possesses. And that’s precisely the point for the Israelis: the guessing game swirling over the proliferation community keeps Israel’s enemies in the region on their toes.
2. Israel Fooled the U.S. to Get Its Program Off the Ground:
The Iranian Government has been caught building enrichment facilities by western intelligence agencies twice before. In 2002, a dissident Iranian group provided information to the United States pointing to a large-scale enrichment facility at Natanz. In 2009, U.S. and European intelligence uncovered another enrichment facility at Fordow buried deep into a mountain. But Iran isn’t the only country that has deliberately deceived the United States and the international community in order to provide time for a full-on nuclear program; the Israelis, as Walter Pincus wrote in a Washington Poststoryearlier this year, “blazed [the] trail decades ago.”
In the 1950s and early 1960s, the Israeli Government repeatedly stonewalled U.S. requests for information on possible weapons development and at times purposely lied to their U.S. allies in the hope of giving the nuclear program more room to breath. In 1960, Israel referred to its Dimona reactor both as a “textile plant” and as a “metallurgic research installation” to the U.S. State Department. Foreign minister Shimon Peres assured President John F. Kennedy in a 1963 meeting in the Oval Office that Israel would “not introduce nuclear weapons to the region.”
President Kennedy was so concerned about a possible Israeli nuclear weapons program that he demanded Israel admit American inspectors into Dimona to snoop around. The Israelis agreed to those requests, but made sure that those visits would not lead to anything incriminating: U.S. inspectors, according to a long-read investigative report in The Guardian, were not permitted to bring their own equipment or collect samples at the site.
3.Why Israel Wanted a Bomb in The First Place:….
4. The World Has Long Wanted Israel to Join the NPT:
Ever since 1995, when signatories of the Nuclear Non-Proliferation Treaty officially called for the “establishment by regional parties of a Middle East zone free of weapons of nuclear and all other related weapons of mass destruction,” the United Nations has attempted to convince Israel that signing the NPT and allowing IAEA inspectors into its facilities is the best way to accomplish that objective. Israel, however, has refused to grant those requests and has long argued that Israel’s nuclear weapons program (which the country continues to neither confirm nor deny) is not nearly the biggest threat to the Middle East’s security.
The atomic bombing of Hiroshima at the end of World War II, alongside the bombing of Nagasaki days later, one of the deadliest military actions undertaken in human history. A new study has been able to use human tissue samples to understand precisely how much radiation victims absorbed in their bones. It’s nearly twice the lethal amount.
A weapon drastically different than any other ever used in war, the atomic bomb in Hiroshima instantly killed over 100,000 people and left thousands more dealing with radiation fallout. By the end of 1945, it is estimated that 160,000 people had been killed directly from the bombing. Several historians have argued that while the bombs effectively ended World War II, their unprecedented destructive capabilities started the next global conflict, the Cold War, at the exact same time.
Attempting to measure the damage done to Hiroshima by the atomic bomb overwhelmed science for decades. There were simply no computers or radiation-measuring devices capable of understanding the damage. Personal stories, like those of the survivors describe in John Hershey’s Hiroshimaand art works of survivors, took hold as the dominant narratives.
But that didn’t mean scientists weren’t trying. When the Atomic Bomb Casualty Commission (ABCC) formed in 1947, the agency quickly realized it would need long term study to understand what had happened. Japanese scientists like E. T. Arakawa and Takenobu Higashimura were releasing studies about the effects of the bombings by the early 1960s.
In 1973, Brazilian physicist Sérgio Mascarenhas was trying to date archaeological items in his home country based on radiation absorption. Radiation occurs naturally in sand through elements like thorium, and techniques like radiocarbon dating use similar principles.
However, Mascarenhas realized that this method might have applications beyond archaeological items. He flew to Hiroshima and, with help from the Institute of Nuclear Medicine in Hiroshima, was able to obtain a jawbone from a bombing victim’s body. While he gained some understanding of what the victim’s body had endured, technical issues stood in his way. He was unable to separate background radiation levels from the bomb blast radiation.
Flash forward four decades later and Angela Kinoshita of Universidade do Sagrado Coração in São Paulo State has reexamined the jawbone using modern technology. Kinoshita’s team was able to determine that the jawbone absorbed 9.46 grays of radiation. A mere 5 grays can be fatal. That number lines up with measurements taken of bricks and other inorganic objects measured at the time. The work is published in PLOS ONE.
Beyond gaining a better understanding of what happened to the victims of Hiroshima, who ranged from prisoners of war to soldiers to civilians, the study offers insight into what might happen if a nuclear weapon was ever used again.
“Imagine someone in New York planting an ordinary bomb with a small amount of radioactive material stuck to the explosive. Techniques like this can help identify who has been exposed to radioactive fallout and needs treatment,” says study co-author Oswaldo Baffa of the University of São Paulo in a press statement. Source: Discover
Thomas Jones digs up Carol Barton’s research article from 2001, in which she relayed her findings that, between 1972 and 1996, the risk of child leukaemia within ten kilometres of Aldermaston and Burghfield was double the rate for the UK as a whole (LRB, 5 April). Barton was then a consultant haematologist at the Royal Berkshire Hospital. ‘Until the cause of cancer is fully understood, and what the part of radiation in the process could be,’ she wrote, ‘no firm measures can be taken to redress the balance.’
Research has moved on since then. More than sixty epidemiological studies worldwide have examined the incidence of cancer in children near nuclear power plants (NPPs): most indicate increases in leukaemia. These include the landmark 2008 KiKK study commissioned by the German government, which found relative risks of 1.6 in total cancers and 2.2 in leukaemias among infants living within five kilometres of all German NPPs.
A number of hypotheses have been proposed to explain these findings. One is that the increased cancers arise from the exposure of pregnant women near NPPs to radiation. However, any theory has to account for the greater than a thousand-fold discrepancy between official estimates of radiation doses from nuclear emissions and the observed increases in cancer risk. It may be that radiation exposures from spikes in NPP radionuclide emissions are significantly larger than the averages recorded in official estimates. In addition, the risks to embryos and foetuses from radiation exposure are much greater than to adults, and the blood-forming tissues in embryos and foetuses are even more radiosensitive.
We speak of “dumb creatures” because animal utterances are largely incomprehensible to the human ear. But animals can show us things. And if you know how to look, they might even give you warning signals. Bugs, for example, give warnings where human perception fails. But to understand those warnings, you have to learn how to read their signals.
You can find the insect drawings of the Swiss artist and scientific illustrator, Cornelia Hesse-Honegger, in museums and galleries all over the world. Most of them reflect (and praise) the breathtaking beauty of the insect realm. But their beauty can be deceptive.
In 1987, one year after the Chernobyl nuclear disaster, Hesse-Honegger came across deformed leaf bugs in areas of Sweden that had been hit hard by fallout from Ukraine. She sensed that something was seriously wrong, even though what she saw did not come as a total surprise. Hesse-Honegger had already been working for many years as a scientific illustrator for the Natural History Museum at the University of Zurich. As early as 1967 she had drawn mutations of drosophila fruit flies and houseflies that had been exposed to radiation in the lab.
In the June 19, 2014 video [below on original ] by Michael Segal for Nautilus, Hesse-Honegger explains her background and work.
After studying the bugs in Sweden she illustrated mutations in many places and documented them in her book Why I Am in Österfärnebo? She did field studies near the Krümmel nuclear power plant in Germany and the French reprocessing facility in La Hague, and she made drawings near Three Mile Island and the nuclear test site in Nevada. Logically, one of her insect illustration books is called “The Future’s Mirror.”
In October 2016, she was invited to Japan to give the opening speech at the Citizen-Scientist International Symposium on Radiation Protection in Nihonmatsu, where, at the same time, she showed her work at the Fukushima Art Biennale. But she also took the opportunity to conduct a field study around the Fukushima nuclear power plant. Her studies focus on what are called true bugs — or Heteroptera. These insects belong to the phylum Arthropoda and are a suborder of Hemiptera.
“Since the accident at the Chernobyl nuclear power plant in April 1986 I have collected 18,000 true bugs, cicada and ladybird beetles,” Hesse-Honegger says. “I have conducted epidemiological studies in areas with nuclear power plants, nuclear reprocessing plants, nuclear test areas and the nuclear factories at Hanford. After collecting the true bugs, I examine them and paint some of them with the help of my binocular microscope. With my watercolors I show the quality of disturbances. With the help of maps I can demonstrate the percentage and distribution of disturbances.”
Everywhere she encountered heteroptera bugs and drosophila flies with distinct mutations. Her comment: “While the natural proportion of mutated insects is just one percent, in the places I studied, up to one in five insects shows physical damage. The damage is likely to be caused by the ingestion of radioactive particles.”
What is really alarming, though, is that injured insects are found not only where you might expect them — near the sites of nuclear catastrophes — but also, as Hesse-Honegger discovered, in the vicinity of well-maintained Swiss nuclear power plants under normal operating conditions.
“That is the real catastrophe,” comments Hildegard Breiner, Austrian anti-nuclear activist and a fellow Nuclear-Free Future Award laureate, (in 2015, the Nuclear-Free Future Award Foundation gave its award in the category of Education to Hesse-Honegger.) Breiner shares Hesse-Honegger’s suspicion that bugs and other creatures with short reproductive cycles tell us that “normal operating conditions” at nuclear power plants are anything but normal.
Hesse-Honegger’s work has also inspired other artists, as the short cut-out animation below [on original] by Mary Pedicini illustrates. It includes Hesse-Honegger’s illustrations along with images by the photographer and early motion picture pioneer, Eadweard Muybridge.
The scientist/illustrator also raises her voice against other threats which go mostly unmentioned compared to the more obvious threat scenarios. One such example is the long-term danger of weapons equipped with depleted uranium. The reactions to “bug warnings” and the dangers of depleted uranium indicate that low-level radiation is an issue widely ignored and poorly understood.
Homeland Preparedness News 27th April 2018, A new paper from the Nuclear Threat Initiative (NTI) provided
recommendations for mitigating risks related to separated plutonium. As compared to highly enriched uranium (HEU), separated plutonium has not
received enough attention as a security risk, NTI Counselor John Carlson said in the paper, titled “Mitigating Security Risks from Separated Plutonium: Some Near-Term Steps.”
Eight countries currently hold more than 375 metric tons of separated plutonium, which is produced by reprocessing irradiated nuclear fuel. The paper recommends minimizing stocks and specific actions in production, storage and use of the material. “Even small quantities [of plutonium] could be of interest to terrorists if they see opportunities for acquiring plutonium in a number of locations or for use in a radiological dispersal device,” Carlson said. https://homelandprepnews.com/stories/28131-nuclear-threat-initiative-highlights-separated-plutonium-security-risks/
In an article published in PLOS ONE, Brazilian researchers describe the first retrospective dosimetric study by electron spin resonance spectroscopy using human tissue from nuclear attack victimsFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO
The bombing of the Japanese cities Hiroshima and Nagasaki by the United States in 1945 was the first and only use of nuclear weapons against civilian targets. A series of studies began in its aftermath to measure the impact of the fallout, in terms of both the radiation dose to which the victims were exposed and the effects of this exposure on DNA and health in general.
Continuing research that started in the 1980s under the leadership of physicist Sérgio Mascarenhas, Full Professor at the University of São Paulo (USP), Brazilian scientists have published an article in the journal PLOS ONE describing a method of precise measurement of the radiation dose absorbed by the bones of victims of the nuclear bombs dropped on Japan.
The investigation was conducted during the postdoctoral research of Angela Kinoshita, currently a professor at Universidade do Sagrado Coração in Bauru, São Paulo State. Her supervisor was then Oswaldo Baffa, Full Professor at the University of São Paulo’s Ribeirão Preto School of Philosophy, Science & Letters (FFCLRP-USP).
“We used a technique known as electron spin resonance spectroscopy to perform retrospective dosimetry. Currently, there’s renewed interest in this kind of methodology due to the risk of terrorist attacks in countries like the United States,” Baffa said.
“Imagine someone in New York planting an ordinary bomb with a small amount of radioactive material stuck to the explosive. Techniques like this can help identify who has been exposed to radioactive fallout and needs treatment.”
As Kinoshita explained, the study is unique insofar as it used samples of human tissue from victims of the bomb dropped on Hiroshima.
“There were serious doubts about the feasibility of using this methodology to determine the radiation dose deposited in these samples, because of the processes involved in the episode,” she said. “The results confirm its feasibility and open up various possibilities for future research that may clarify details of the nuclear attack.”
The equipment used in the investigation was purchased during a project coordinated by Baffa and supported by the São Paulo Research Foundation – FAPESP.
Origins
In the 1970s, when he was teaching at the University of São Paulo’s São Carlos Physics Institute (IFSC-USP), Mascarenhas discovered that X-ray and gamma-ray irradiation made human bones weakly magnetic. The phenomenon, known as paramagnetism, occurs because the hydroxyapatite (crystalline calcium phosphate) in the mineral portion of bone tissue absorbs carbon dioxide ions, and when the sample is irradiated, the CO2 loses electrons and becomes CO2-. This free radical serves as a marker of the radiation dose received by the material.
“I discovered that we could use this property to perform radiation dosimetry and began using the method in archeological dating,” Mascarenhas recalled.
His aim at the time was to calculate the age of bones found in sambaquis (middens created by Brazil’s original inhabitants as mounds of shellfish debris, skeletons of prehistoric animals, human bones, stone or bone utensils, and other refuse) based on the natural radiation absorbed over centuries via contact with elements such as thorium that are present in the sand on the seashore.
On the strength of this research, he was invited to teach at Harvard University in the United States. Before leaving for the US, however, he decided to go to Japan to try to obtain samples of bones from victims of the nuclear bombs and test his method on them.
“They gave me a jawbone, and I decided to measure the radiation right there, at Hiroshima University,” he said. “I needed to prove experimentally that my discovery was genuine.”
Mascarenhas succeeded in demonstrating that a dosimetric signal could be obtained from the sample even though the technology was still rudimentary and there were no computers to help process the results. The research was presented at the American Physical Society’s annual March Meeting, where it made a strong impression. Mascarenhas brought the samples to Brazil, where they remain.
“There have been major improvements in the instrumentation to make it more sensitive in the last 40 years,” Baffa said. “Now, you see digitally processed data in tables and graphs on the computer screen. Basic physics has also evolved to the extent that you can simulate and manipulate the signal from the sample using computational techniques.”
Thanks to these advances, he added, in the new study, it was possible to separate the signal corresponding to the radiation dose absorbed during the nuclear attack from the so-called background signal, a kind of noise scientists suspect may have resulted from superheating of the material during the explosion.
“The background signal is a broad line that may be produced by various different things and lacks a specific signature,” Baffa said. “The dosimetric signal is spectral. Each free radical resonates at a certain point on the spectrum when exposed to a magnetic field.”
Methodology
To make the measurements, the researchers removed millimeter-scale pieces of the jawbone used in the previous study. The samples were again irradiated in the laboratory using a technique called the additive dose method.
“We added radiation to the material and measured the rise in the dosimetric signal,” Baffa explained. “We then constructed a curve and extrapolated from that the initial dose, when the signal was presumably zero. This calibration method enabled us to measure different samples, as each bone and each part of the same bone has a different sensitivity to radiation, depending on its composition.”
Thanks to this combination of techniques, they were able to measure a dose of approximately 9.46 grays (Gy), which is high in Baffa’s view. “About half that dose, or 5 Gy, is fatal if the entire body is exposed to it,” he said.
The value was comparable with the doses obtained by other techniques applied to non-biological samples, such as measurement of the luminescence of quartz grains present in brick and roof tile fragments found at the bomb sites. According to the authors, it was also close to the results of biological measurement techniques applied in long-term studies using alterations in survivors’ DNA as a parameter.
“The measurement we obtained in this latest study is more reliable and up to date than the preliminary finding, but I’m currently evaluating a methodology that’s about a thousand times more sensitive than spin resonance. We’ll have news in a few months,” Mascarenhas predicted.
About São Paulo Research Foundation (FAPESP)
The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. For more information: http://www.fapesp.br/en.
The strategy of the desperate is to downplay and dismiss. A major nuclear disaster is more than just an inconvenient truth for an industry that doesn’t want you to know it kills people. As a result, when a serious nuclear accident happens — arguably always preventable and therefore not strictly an accident — there is a scramble to present the event as largely insignificant.
Many myths are quickly put about, usually centered on how few people immediately died, a completely misleading statistic since nuclear power plant disasters do not usually kill people instantly. But over the long-term, their legacy is indeed both considerable and often deadly.
In the newest edition of our periodic Thunderbird newsletter, we look at the facts about the Chernobyl disaster — and touch on one welcome piece of fiction in the form of a novel.
The disparities over the death count are used to downplay and even dismiss the terrible and long-lasting after effects of Chernobyl. But focusing only on fatalities also serves to diminish the disaster’s impact. It can take years before fatal illnesses triggered by a nuclear accident take hold. This creates a challenge in calculating just who eventually died due to the accident and who suffered non-fatal consequences.
Exposure to ionizing radiation released by a nuclear power plant (and not just from accidents but every day) can cause serious non-fatal illnesses as well. These should not be discounted. Arguably, neither should post accident psychological trauma.
All the populations affected by Chernobyl have been inadequately studied and monitored — whether they lived inside the former Soviet Union or elsewhere in Europe where the radioactive plume also contaminated lands and people.
The Chernobyl liquidators are a group most often cited as they were dispatched to the stricken nuclear plant in the immediate aftermath, as well as for at least the subsequent two years, to manage and endeavor to “clean up” the disaster. They included military as well as civilian personnel such as firefighters, nuclear plant workers and other skilled professionals. More information is still emerging on their fate and that of their descendants.
It is generally accepted that there were about 800,000 liquidators but only a small portion of them were subject to medical examinations. By 1992 it was estimated that 70,000 liquidators were invalids and 13,000 had died. These estimates rose to 50,000 then to 100,000 deaths among liquidators in 2006. By 2010, Yablokov et al. estimated a death toll of 112,000 to 125,000 liquidators.
Even the Russian authorities admit findings of liquidators aging prematurely, with a higher than average number having developed various forms of cancer, leukemia, somatic and neurological problems, psychiatric illnesses and cataracts. The UN Office for the Coordination of Humanitarian Affairs found a statistically significant increase in leukemia among Russian liquidators who were in service at Chernobyl in 1986 and 1987.
There are similar findings among general populations although, again, these have been hard to track. While countless numbers may have eventually died from Chernobyl-related illnesses, equal or even greater numbers likely survived and were forced to live with debilitating and chronic medical conditions as well as psychological trauma.
The widely debunked 2003-2005 Chernobyl Forum accounting is the record most often quoted, and yet it is utterly compromised. It was produced by the nuclear promoting International Atomic Energy Agency, which ignored its own data that indicated there would be 9,000 future fatal cancers in Belarus, Russia and Ukraine. The IAEA instead claimed there would be no more than 4,000. Both numbers are gross underestimations.
The report focused only on the most heavily exposed areas in making its predictions. It ignored the much larger populations in the affected countries as a whole, and in the rest of the world, who have been exposed to lower but chronic levels of radiation from Chernobyl.
The later TORCH Report exposed the flaws in the Chernobyl Forum as did IPPNW in its own report. TORCH predicts at least 30,000 and maybe as many as 60,000 excess cancer deaths worldwide due to the accident. An analysis of 5,000 Russian studies, by the late Soviet scientist, Alexey Yablokov and colleagues, puts the number of premature deaths due to Chernobyl as likely to soar as high as one million people.
In other studies, elevated rates of thyroid cancer were discovered in Belarus, Ukraine and Russia, particularly among children, where the preventive pill, potassium-iodide (KI), was not distributed. In Poland, where KI was distributed, incidences were extremely low.
Outside the former Soviet Union, impacts were also significant with about 40% of Europe’s land surface radiologically contaminated.
Dr. Wladimir Wertelecki, a physician and geneticist, discovered, alarmingly, that the negative health effects caused by Chernobyl did not stop with those exposed directly. His research, focused in Polissia, Ukraine, noted birth defects and other health disturbances among not only those who were adults at the time of the Chernobyl disaster, but their children who were in utero at the time and, most disturbingly, their later offspring.
Pierre Flor-Henry in his research, even found medical changes resulting from apparent psychological responses. He noted that schizophrenia and chronic fatigue syndrome among a high percentage of liquidators were accompanied by organic changes in the brain. This suggested that various neurological and psychological illnesses could be caused by exposure to radiation levels between 0.15 and 0.5 sieverts.
Nevertheless, the IAEA and the World Health Organization (WHO), given their supposedly august credentials, are cited as the bodies of record on post-Chernobyl fatalities and health impacts. But there is a fundamental reason why the WHO cannot be trusted.
On May 28, 1959, the WHO made an agreement with the IAEA that would effectively gag the agency on any nuclear issue from that day forth. The agreement gave the IAEA a veto on any actions by the WHO that relate in any way to nuclear power. The IAEA’s stated mission is to “accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world.” So clearly, there is a major conflict of interest at work here.
Not only people but animals — both wild and domestic — have been harmed by the Chernobyl disaster. This damage is likely permanent as it has been passed down through generations via DNA. The research by Dr. Timothy Mousseau finds birds around Chernobyl with low to zero sperm counts, cataracts, diminished brain size and truncated longevity. Stray dogs continue to proliferate around the Chernobyl nuclear site. Wild boars in Europe remain too radioactive to eat. Insects have mutated and micro-organisms have disappeared.
There are some bright and hopeful signs however. Much humanitarian work has gone on over the decades to bring relief to those suffering the Chernobyl after-effects. The disaster — and the subsequent one at Fukushima — changed the minds of the leaders in power at the time, Mikhail Gorbachev and Naoto Kan. These men now advocate for an end to the use of nuclear power. Several countries renounced nuclear power in the wake of these disasters or reinforced their policies to phase out nuclear and turn to renewables.
And there is even some welcome fiction about Chernobyl, in the form of a searingly beautiful and haunting first novel by Irish writer Darragh McKeon. We encourage you to read All That Is Solid Melts Into Air for a vivid account of the very real characters he portrays living through the Chernobyl ordeal.
AMARILLO, Texas (Reuters) – In a sprawling plant near Amarillo, Texas, rows of workers perform by hand one of the most dangerous jobs in American industry. Contract workers at the U.S. Department of Energy’s Pantex facility gingerly remove the plutonium cores from retired nuclear warheads.
Although many safety rules are in place, a slip of the hand could mean disaster.
In Energy Department facilities around the country, there are 54 metric tons of surplus plutonium. Pantex, the plant near Amarillo, holds so much plutonium that it has exceeded the 20,000 cores, called “pits,” regulations allow it to hold in its temporary storage facility. There are enough cores there to cause thousands of megatons of nuclear explosions. More are added each day.
The delicate, potentially deadly dismantling of nuclear warheads at Pantex, while little noticed, has grown increasingly urgent to keep the United States from exceeding a limit of 1,550 warheads permitted under a 2010 treaty with Russia. The United States wants to dismantle older warheads so that it can substitute some of them with newer, more lethal weapons. Russia, too, is building new, dangerous weapons.
The United States has a vast amount of deadly plutonium, which terrorists would love to get their hands on. Under another agreement, Washington and Moscow each are required to render unusable for weapons 34 metric tons of plutonium. The purpose is twofold: keep the material out of the hands of bad guys, and eliminate the possibility of the two countries themselves using it again for weapons. An Energy Department website says the two countries combined have 68 metric tons designated for destruction – enough to make 17,000 nuclear weapons. But the United States has no permanent plan for what to do with its share.
Plutonium must be made permanently inaccessible because it has a radioactive half-life of 24,000 years.
“A MUCH MORE DANGEROUS SITUATION”
Edwin Lyman, a physicist at the Union of Concerned Scientists, a science advocacy group based in Washington, says solving the problem of plutonium storage is urgent. In an increasingly unstable world, with terrorism, heightened international tensions and non-nuclear countries coveting the bomb, he says, the risk is that this metal of mass annihilation will be used again. William Potter, director of the James Martin Center for Nonproliferation Studies at the Middlebury Institute of International Studies, told Reuters: “We are in a much more dangerous situation today than we were in the Cold War.”
Washington has not even begun to take the steps needed to acquire additional space for burying plutonium more than 2,000 feet below ground – the depth considered safe. Much of America’s plutonium currently is stored in a building at the Savannah River Site in South Carolina – like Pantex, an Energy Department site. Savannah River used to house a reactor. Local opponents of the storage, such as Tom Clements, director of SRS Watch, contend the facility was never built for holding plutonium and say there is a risk of leakage and accidents in which large amounts of radioactivity are released.
The Energy Department has a small experimental storage site underground in New Mexico. The department controls the radioactive materials – plutonium, uranium and tritium – used in America’s nuclear weapons and in the reactors of nuclear-powered aircraft carriers and submarines. In a Senate hearing in June 2017, Energy Secretary Rick Perry said the Energy Department has been in talks with New Mexico officials to enlarge the site. Environmental groups there have strongly opposed expansion.
Under an agreement with Russia, the United States was to convert 34 metric tons of plutonium into fuel for civilian reactors that generate electricity. The fuel is known as MOX, for “mixed oxide fuel.” Plutonium and uranium are converted into chemical compounds called oxides, and mixed together in fuel rods for civilian nuclear power plants. The two metals are converted into oxides because these can’t cause nuclear explosions. But the U.S. effort has run into severe delays and cost overruns.
The alternative method is known as dilute-and-dispose. It involves blending plutonium with an inert material and storing it in casks. The casks, however, are projected to last only 50 years before beginning to leak, and so would need to be buried permanently deep underground.
Radioactively-hot particles detected in dusts and soils from Northern Japan by combination of gamma spectrometry, autoradiography, and SEM/EDS analysis and implications in radiation risk assessment, Science Direct
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