Nuclear Testing in Kiribati: Global, Individual, and Environmental Consequences

The British and American thermonuclear weapons tests off of Kiritimati (Christmas Island) and over Malden Island in the 1950s were only the beginning of the international nuclear arms race, but the results were revolutionary at the time, and had lasting impacts worldwide. At the global political level, Britain became a thermonuclear power, Americans caused the Cuban missile crisis, and more locally, Kiritimati was transformed from mostly uninhabited coconut plantations into a tropical tourist locale. At an individual human level, veterans of the tests from Kiritimati, Great Britain, New Zealand, and Fiji were exposed to poisonous levels of radiation, which quite possibly made its way into the waters and wildlife of the area around Kiritimati and Malden Islands. Although they only make up a small percentage of nuclear tests that have occurred around the world, the nuclear tests in Kiribati were consequential and have sparked many controversies on global, national, and individual scales.

Kiritimati and Malden islands, part of what is now the Republic of Kiribati, were two of many nuclear test sights for Britain and the United States. They were considered ideal locations for testing in terms of geographical location, and physical and human environments. Both islands are in the middle of the Pacific Ocean, surrounded by miles of open ocean, and were at the time sparcely populated. Both islands had been annexed to the British in 1888, allowing the British and the United States to easily circumvent any potentially sticky political situations occurring before or during the tests.

Kiritimati has a total of 125 square miles of land, giving it the largest land area of any atoll in the world. This provided a perfect home base for the tests, because it could hold the number of service men and the infrastructures needed. Before the tests, the island was inhabited by only two-to-three-hundred coconut plantation laborers, meaning that large-scale evacuations wouldn’t be necessary.

Malden Island, on the other hand, is due south of Kiritimati, and invisible on most maps, with an area of fifteen square miles. Preceding the tests it was uninhabited. Although the British never explicitly referred to Malden Island as a target location for the bombs, it was likely used for such purposes.

The British were the first to use Kiritimati and Malden Islands as nuclear test spots, although they had previously tested in Australia as well. The Australia tests resulted in the perfection of a British atomic bomb by 1953 (Nuclear Weapons Archive). But by the time this happened, the United States had already designed and tested a thermonuclear bomb, which released a much higher energy yield than the atomic bomb, and was much more economical. In nuclear fission, which is key to the production of an atomic bomb, the nucleus of the atom explodes, instantaneously releasing enormous amounts of energy all at once as the “atomic nucleus splits into fragments” and the “energy is expelled explosively and violently” (Bellis). However, the production of a thermonuclear bomb, involves both fission and fusion. The fission reaction starts the fusion reaction, and the thermonuclear bomb gains its energy from the fusion of hydrogen isotope nuclei, forming helium nuclei (Bellis). In addition to producing a much higher yield, thermonuclear weapons use much less uranium than atom bombs for the amount of energy that they yield. It was this knowledge, demonstrated by the United States over Bikini Atoll, which led the British government to the conclusion that they needed to perform more nuclear tests in the South Pacific (NuclearWeaponsArchive).

Another incentive for the British to use Kiritimati and Malden was that that they had agreed to test only atom bombs in Australia.  “The testing agreement with the Australians, [where they were testing at the time,] had specifically excluded hydrogen weapon trials on their continent 'for safety reasons'” (Resture). It was clear at the time of the tests that thermonuclear testing was more hazardous than atomic testing, so they had to find other testing locations.

Increasing global protests against nuclear weapons in the mid 1950s motivated prompt and continued testing in the islands. If they waited any longer, the British feared a nuclear weapons moratorium would not allow them to “demonstrate [their nuclear weapon] capability to the world.” The moratorium would leave Britain at a disadvantage as compared to the United States and the Soviet Union, who tested their first thermonuclear weapon in November 1955. Winston Churchill, who reportedly said, “We could not expect to maintain our influence as a world power unless we possessed the most up-to-date nuclear weapons” (Resture*), summed up Britain’s decision.

“Operation Grapple” was the official code name for the British series of tests on Kiritimati and Malden. The name originated from “a four-pointed grapnel iron,” which was supposed to represent unity between the British Army, Navy, Air Force, and the Atomic Weapons Research Establishment (AWRE) (Resture). The preparation required for the tests was enormous. Kiritimati, which was to be the test base, was almost completely undeveloped before the British arrived. An airfield had to be constructed, along with fuel tanks, a facility for distilling salt water, structures to house the workers, and paved roads. Fire trucks, construction tools and vehicles, materials for building the infrastructure, fuel, other equipment, and over one thousand laborers, servicemen, and scientists, all had to be brought by boat to the islands. In less than a year, a nuclear testing base had been built, and the British decided that they were ready to begin testing.

On 15 May 1957 the first test, Grapple 1, was detonated over Malden Island. It only yielded 300 kilotons, which was a disappointing result, because it was it was supposed to yield one megaton. To cover up this failure, Britain detonated a second bomb, which yielded 700 kilotons. However, in this trial, they really just exploded an enormous atom bomb, indicating that their grasp on thermonuclear technology was still weak. Grapple 1 was significant because it indicated Great Britain’s near desperation to show the world that they had nuclear capabilities.

After the failed attempts at Malden Island, the British decided to switch the tests to the southern end of Kiritimati, in order to save time and money. In November 1957 they detonated a hydrogen bomb of 1.8 megatons. (To put this in perspective, the atomic bomb that was dropped on Hiroshima was 15 kilotons, or 120 times less powerful.) This operation, code-named Grapple X, had fifty percent more powerful primary fission than the previous test, and simplified thermonuclear secondary fusion as well, officially allowing Great Britain to announce its thermonuclear power capabilities.

The title of "thermonuclear power" was, however, slightly misleading, as the bomb had several gaping flaws. First, it was extremely costly and inefficient because it used an excessive amount of enriched uranium. The second problem was that the actual yield was only half that predicted by Brittish scientists.  Because of this, the bomb demolished buildings and damaged infrastructure on the island when detonated, including a “ten ton diesel generator” (Resture). One serviceman on the island reported:  "We all turned round and we saw the blast hit the palm trees and bend them over. We were informed later...that the bomb had been dropped slightly lower than they anticipated and it was far bigger than they had imagined." (Resture)

It is clear from this report that there was not yet a strong grasp of the nature of the bomb that had been designed. Thus, in April 1958, another bomb, Grapple Y, was detonated. Grapple Y yielded three megatons, a record for the British. Moreover, the yield came from thermonuclear reactions rather than fast fission, which made it a true hydrogen bomb. It was also predicted to be three megatons, demonstrating that the British scientists now knew what they were doing.

Despite the success of Grapple Y, there was still a need to conduct further tests. The British had made an agreement with the United States that the two nations would share information about their thermonuclear technology, and knew that the amount and quality of information they would receive from the U.S relied on how much they could give. Additionally, the sense of urgency to complete all their nuclear testing before the pending nuclear moratorium pushed them to complete one final series of tests. These tests, which took place from August through October 1958, were known as Grapple Z. The basic idea of the trials was to develop a radiation-immune one-megaton warhead. This implied a weapon that wouldn’t detonate if it came into contact with other radioactive materials, such as another bomb. A weapon like this sparked the interest of the United States; the Cold War was perpetuated, in part, by the constant fear of becoming victim to a nuclear attack. By October, the British series of detonations resulted in a viable weapon, and under the US-UK Mutual Defense Agreement of 1958, the Americans shared their hydrogen bomb designs with the British.

Almost as soon as the British had developed this newest weapon technology, the 1958 moratorium took place in which the USSR, the US, and the British, agreed to stop testing. Not long after, in 1968, the Nuclear Non Proliferation Treaty was signed, which was an agreement between countries around the world to discontinue the development of nuclear weapons. However, in between the international moratorium and the test ban treaty, the Soviet Union “initiated an unprecedented series of tests” beginning a new series of tests and (NuclearweaponArchive) leading the U.S to follow suit. Because of the US-UK Mutual Defense Agreement, the British allowed the United States to test at Kiritimati.  The American trials at Kiritimati and and Johnston Island (an atoll near Hawaii) were code named "Operation Dominic."

Operation Dominic was comprised of 36 tests, including 29 airdrops (24 of which were conducted over Kiritimati), five rocket-launched tests, and two tests of “operational weapon systems––the Polaris submarine launched ballistic missile and the ASROC anti-submarine rocket” (NuclearweaponArchive). The operation was most notabe due to its tests over Johnston Island, because these culminated with the Cuban Missile Crisis in 1962, which is the closest the world has come to nuclear war. However, the Limited Test Ban treaty of 1963, which was a product of the Cuban Missile Crisis, “banned nuclear tests in the air and in the water” (CTBTO), and therefore was extremely important for Kiritimati because it ended testing off the island for good.

The Limited Test Ban treaty did not end the discussions and the accusations that followed the testing. In the aftermath of Operation Grapple and Operation Dominic, many controversies arose over the safety precautions taken by the British and American governments, and concerns about critical knowledge that might have been kept from servicemen and laborers involved with the tests.

During the tests, servicemen and scientists were on both Malden Island and Kiritimati, on ships near the island, and in planes detonating or surveying the bombs. Those who were working on Malden Island were most likely contaminated by the tests, due to the lack of safety precautions taken. Men who were on ships when the bombs were detonated were supposedly thirty or forty miles away, but could have very well been contaminated with radioactive fallout. Planes that flew through the area just after the bombs were detonated were also most likely at risk.

Many firsthand accounts from veterans who were on the islands or ships at the time of detonations, report that they did not wear any protection from the blasts other than the clothes on their backs. Although the British claimed that servicemen wore suits that would prevent irradiation, others maintain that this was not always the case.  Moreover, although at first the British Ministry of Defense stated that tests off of Kiritimati were detonated far from shore, journalist Eamonn O’Neill uncovered a 1958 report of the tests, which documented ground zero for one of the tests as a quarter mile away from shore, a dangerous proximity for people on the island.

Before going to Malden Island for the second test, one technician was assured that “health physicists” had monitored the island and determined that it was safe. However, the technician also noticed that there were none of the flies, lizards, or booby birds that he noticed on Kiritimati, and that the health physicists were nowhere to be found (Resture). When his radiation level was taken the next day, it was extremely high. The technician remarked, “this was a contaminated area and we should have been issued with protective clothing” (Resture).

Physics professor Joseph Rotblat of the University of London claims that although the tests off of Kiritimati were technically airbursts and were therefore considered “clean,” high altitude bursts can still lead to radioactive fallout. Consequently, irradiation might well have occurred over the island after the tests, which would be highly unsafe for any residing servicemen.  Whereas journals and newspapers determined that the rain after the tests was unimportant, eyewitnesses report differently. Many servicemen remembered that tests were often accompanied by heavy rainfall. One veteran, Tom Birch, reported rain about ten to fifteen minutes after the April test of Grapple Y. The test had been delayed due to potentially negative weather conditions, but was then carried out before the weather had fully abated.  Birch remembers that the servicemen on the island:

all ran like mad to get away from the rain it was so torrential. Lost (sic) of men must have been caught out in the open though...From the way that they were acting it was clear that something had gone far wrong. The whole thing appeared abnormal, unusual. Landing crafts and other vessels were being started up all around us so that we could be evacuated. As it turned out we never actually left the island, the rain sort of cleared up and we were left looking at each other. It all ended in complete chaos and confusion.

This is just one of many personal accounts of the unsafe procedures on the island. However, the problem is that up until recently there were no official records were made public that specified radiation levels or other indicators that the tests might not have been safe.  In the past few decades, lawsuits against the British government have begun to reveal previously undisclosed material about the nuclear tests, leading to the belief that many of the tests were closer to shore than was previously thought, and that many necessary safety precautions were simply not taken. That being said, although there have been two recent studies conducted by Britain and Australia about the safety and potential harm of the tests, both the methods and the resulting statistics have been criticized as faulty. The studies demonstrate the subjectivity and difficulties involved in determining the safety of the tests, as the British study finds that they were unsafe whereas the Australian study concludes that they had no negative effects. Moreover, personal anecdotes from veterans have not been deemed as a reliable source of evidence by the Ministry of Defense.  Even though medical records from an Australian blood cancer study of five hundred veterans show exposure to radiation, the Ministry of Defense does not believe that this number is enough to prove the dangerous nature of the tests. 

It is also likely that the pilots who were manning the airplanes involved in the bomb testing were at risk of being exposed to high levels of radiation. The “Sniffers,” or planes that the British used to perform “cloud sampling” could not go as high as needed, thus putting many pilots in risky positions, as they had to fly through the mushroom cloud. Other pilots involved in photographing the tests reported accidentally coming into contact with the mushroom cloud as well (Resture). The servicemen required to decontaminate the aircraft after the tests were also arguably endangered. One serviceman reported, “We were cleaning off barrier paint above me and water came off the back of the wing. I was only wearing cotton whites so, of course it went straight through, and bearing in mind that it was contaminated water coming off I wasn't a very happy person underneath” (Resture). Shortly after the tests, this serviceman developed health problems that “have persisted ever since” (Resture).

While environmental concerns haven’t been taken up by the governments, or very thoroughly researched, it is clear that the tests had detrimental impacts on the island environment and wildlife at the time. After the blasts, large numbers of dead fish rose to the surface of the water and floated ashore, and servicemen had to shoot thousands of birds that had been blinded by the light of the explosion (Resture).  

Whether the Gilbertese people living on the island were affected by the tests is also subject to much controversy. It is highly likely that if the servicemen and scientists who were on the island at the time of the tests were subject to radiation poisoning, then the islanders would be as well. During some of the tests, the islanders were simply told to turn their backs to the blasts, rather than being put up in huts, making them more susceptible to irradiation. Moreover, the islanders knew even less about the dangers of radiation than the British and American workers did, and therefore probably didn’t take any individual safety precautions. The British Government was supposed to block off areas that were dangerous, but it has been suggested that these areas were chosen randomly (Narsey). This is another controversy that is unclear, as there are no records showing whether the “Danger Zones” were actually dangerous, and whether there were other zones that should have been prohibited (Narsey).

After looking at all the individual accounts of possible encounters with radioactive particles, one gets the general sense that the most pertinent problem with the British tests was that both the preparation for the tests and the tests themselves were extremely rushed, and therefore Great Britain did not have a full grasp on the potential dangers of the weapons they were testing. Due to this, “The men who worked in areas known to involve radiation exposure may have been the victims of lax security and safety precautions.”  However, “No details of the doses to which the men on Christmas Island were exposed have been published,”(Resture) and without any much hard evidence, it is almost impossible to prove that men were contaminated. Whether this was the intent of the American and British Governments, and whether the American and British Government knew that being exposed to radiation by the tests would be harmful to servicemen and scientist is still somewhat of a mystery.

This lack of hard evidence has not stopped many Americans, British, Fijian, and New Zealand testing veterans from speaking out and in many cases suing the American and British governments. One organization, The Atomic Claims Group, has over 1000 members, all veterans of nuclear testing off of Kiritimati and Malden Island, who have suffered from some sort of illness associated with irradiation. The members of this group are collectively suing the British Ministry of Defense. As of 2011, The U.S and Great Britain both had very different methods of responding to veterans’ complaints. One British newspaper, the Guardian, has reported that "The UK war pensions scheme requires evidence of a link between service and the US, however, claimants do not have to prove causality, just that they were exposed to radiation and contracted one of the qualifying diseases."

In general, the biggest controversy surrounding the tests has been the amount of knowledge that was known in the 1950s about the harmful nature of thermonuclear detonations. The first atom bombs had only been tested about a decade earlier, which did not give much time for research about the poisonous nature of the bombs. Whether or not that excuses the British Government is a question remaining to be answered. What is known, and admitted by the British Government, is that the tests were carried out in too much haste, with too few resources. Unfortunately, this admission alone has not been enough to persuade the Ministry of Defense, and many veterans of nuclear testing remain uncompensated for their sacrifices today.

Monty Sherwood, Kenyon College


Note:  Jane Resture's website is frequently used by credible sources, though she often does not cite her material. Some of the content on her website is taken directly from No Risk Involved, a book by nuclear test veteran Ken McGinley, and presumably other unknown sources as well. However, much of her research is convincing, and rooted in concrete evidence, revealing pertinent information about the nuclear tests that cannot be found elsewhere. 


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