Nuclear Bombing of Bikini Atoll Summary

  • Last updated on November 10, 2022

The U.S. government tested a multimegaton bomb on Bikini Atoll, contaminating Bikini and several other of the Marshall Islands. The atoll was virtually obliterated by the explosion.

Summary of Event

On March 1, 1954, the United States exploded a seventeen-megaton bomb on Bikini Island, one of the Marshall Islands in the South Pacific. The residents of Bikini had been relocated several years earlier, but the inhabitants of two other atolls downwind of the blast were neither removed nor warned. They suffered a variety of illnesses, many severe, from the effect of fallout. Related health problems would continue to occur. Nuclear weapons;Bikini Atoll Bikini Atoll;nuclear bombing of Nuclear weapons;testing Bravo (nuclear bomb) [kw]Nuclear Bombing of Bikini Atoll (Mar. 1, 1954) [kw]Bombing of Bikini Atoll, Nuclear (Mar. 1, 1954) [kw]Bikini Atoll, Nuclear Bombing of (Mar. 1, 1954) Nuclear weapons;Bikini Atoll Bikini Atoll;nuclear bombing of Nuclear weapons;testing Bravo (nuclear bomb) [g]Pacific;Mar. 1, 1954: Nuclear Bombing of Bikini Atoll[04360] [g]Micronesia;Mar. 1, 1954: Nuclear Bombing of Bikini Atoll[04360] [c]Environmental issues;Mar. 1, 1954: Nuclear Bombing of Bikini Atoll[04360] [c]Cold War;Mar. 1, 1954: Nuclear Bombing of Bikini Atoll[04360] [c]Atrocities and war crimes;Mar. 1, 1954: Nuclear Bombing of Bikini Atoll[04360] [c]Science and technology;Mar. 1, 1954: Nuclear Bombing of Bikini Atoll[04360] Wyatt, Ben Kessibuki, Juda Juda, Tomaki Anjain, Lekoj

The Marshall Archipelago consists of twenty-nine coral atolls and five coral islands in eastern Micronesia. The land area, scattered over 375,000 square miles of ocean, adds up to less than seventy square miles, mostly in atolls. Atolls are formed by coral growing upward from submerged volcanic peaks, creating circles or semicircles of islands and reefs enclosing protected lagoons. Bikini, one of the northernmost atolls, was composed of twenty-six islands on a reef around a lagoon. The islanders relied on the atoll’s abundant marine life for food, but they also grew coconuts and arrowroot, occasionally supplemented by pigs, chickens, and land crabs.

The Marshall Islands were controlled for forty years by the Japanese until the end of World War II, when the archipelago became a trusteeship of the U.S. government. Five weeks after the end of the war, the U.S. joint chiefs of staff began to look for a site for a series of atomic tests. Bikini was chosen because it had a deep-water harbor where target vessels could anchor, it was isolated, and it had a small and easily relocated population of 166 people.

In February, 1946, Commodore Ben Wyatt, American military governor of the Marshalls, flew to Bikini to ask the islanders to leave their land, and Chief Juda Kessibuki assented. The Bikinians were moved to the uninhabited atoll of Rongerik, one-quarter the size of their former home, and left with a two-week supply of food and water. The carrying capacity of Rongerik was insufficent for the new population, and the people soon suffered from hunger and malnutrition.

In June of that year, the bombing of Bikini began, and by December, Eniwetok, another atoll in the Marshall Islands, was also requisitioned. Its inhabitants were moved to a much smaller atoll, with the same results. After two years of near starvation and many requests for help, the Bikinians were moved again. Kili, their new home, was an island, not an atoll with a protected lagoon for fishing. Once again, malnutrition set in.

On March 1, 1954, the United States exploded a hydrogen bomb over Bikini Atoll. This bomb, named Bravo, had more than one thousand times the force of the bomb that had been dropped on Hiroshima, and it was designed to maximize radioactive fallout. Despite a weather report indicating winds headed toward the islands of Rongelap, one hundred miles east of Bikini, and Utirik, three hundred miles east, the inhabitants of the islands were neither removed nor warned.

After the blast, lime from the Bikini reef that had been melted in the blast fell on Rongelap in a white powder, accumulating to a depth of one and one-half inches. Unaware of its nature, children played with it as if it were snow, and the entire population continued to drink water from catch basins and to gather and eat food on which the substance had fallen. By nightfall, the inhabitants found their hair falling out and their skin itching and burning. Many experienced vomiting, achiness, and weakness.

The U.S. Navy vessels nearby were instructed not to rescue the residents for two days. The people of Utirik were rescued three days later. All the 239 irradiated Marshallese were transported to Kwajalein Atoll, where a team of U.S. radiation experts was flown in to study and examine them. In the weeks that followed, the islanders’ blood platelet levels fell by 50 percent, and stillbirths and miscarriages were reported.

The International Commission on Radiological Protection recommends a maximum dose of 0.5 units of radiation (rems) per year; 200 to 300 rems is expected to cause a 50 percent death rate in a nuclear war. It was estimated that the people on Rongelap received a dose of 175 rems, and the people on Utirik 14 rems. These numbers refer only to whole-body exposure; exposure to specific body parts was higher because of the properties of ionizing radiation and the ingestion of contaminated food and water.





The Navy never explained the two- and three-day delays in evacuating the Marshall Islanders but did admit in early 1994 that its personnel had been aware of the wind forecast. Critics have charged that the delay may have been a deliberate attempt to create a population that could be studied to understand the effects of radiation. In the 1940’s, standards for medical experimentation on human subjects were lower than they have become since.


Prior to the bombing of Bikini Atoll, the only data on the effects of radiation exposure Radiation poisoning came from the explosions in Hiroshima and Nagasaki, where the direct effects of the blasts had to be taken into account as well. At that time, medical opinion held that the only effects of radiation exposure were immediate. After the initial examination of the radiation victims on Kwajalein Atoll, the Atomic Energy Commission Atomic Energy Commission, U.S.;health studies (AEC) assigned a medical team from Brookhaven National Laboratory Brookhaven National Laboratory in New York to examine and record the health of the Marshallese over time.

Three months after the blast, the people from Utirik were allowed to return home. The people from Rongelap were returned after three years, although the AEC acknowledged that some radioactivity Radioactive contamination lingered on their island. Returning along with the Rongalapese were some residents who had not been on the island at the time of the blast and who subsequently became affected through the food they ate there.

On their return, the islanders found the ecology of the atoll altered. Animals they had left behind were dead or sick, as were plants and trees. The residents were instructed not to eat arrowroot or coconut crabs, but when food supplies from outside ran low, as they often did, anything edible was consumed. Brookhaven reported that when the people returned to Rongelap, their body levels of radioactivity soared, but the inhabitants were not told, nor were they urged to leave.

The next few years brought more miscarriages and stillbirths. The Brookhaven team, however, was expecting their subjects’ health to return to normal. It was not until 1964, ten years after the bombing, that thyroid abnormalities began to appear in the Brookhaven data, proving for the first time that radioactive fallout has long-term effects. By the 1980’s, approximately forty thyroid tumors had been found in the Rongelap population, four of which were malignant. Furthermore, 90 percent of the people who were under age twelve at the time of the explosion contracted thyroid disease. On Utirik, there were sixteen cases of tumors, three of which were malignant. The high rate of thyroid problems was thought to stem from the similarity of radioactive iodine 131 to normal, stable iodine, which the thyroid gland readily absorbs.

Growth retardation was found in some children who had been under age ten at the time of the blast, particularly boys who had been under five. In 1972, Lekoj Anjain, who had been the youngest child on Rongelap in 1954, died of leukemia.

One important implication of these data was that the younger the persons exposed, the more susceptible they were to radiation-induced disease. Cataracts became frequent among the population. The Marshall Islanders developed the highest rate of diabetes in the world, which may have been caused by the bomb, the subsequent rapid change of diet, or both. A higher-than-normal rate of an assortment of health problems, from anemia to cervical erosion, has been shown, but the incidences have been too few for clear conclusions to be drawn.

The Marshallese were critical of the quality of the health care provided them by the Brookhaven team, and they have been joined in their criticism by other medical personnel who questioned aspects of the research methodology. One departing Brookhaven doctor criticized the program for looking exclusively for evidence of what experts had previously predicted. Throughout the 1960’s and early 1970’s, Brookhaven focused on the effects of acute radiation, in effect dismissing blame from low- and middle-level radiation. This clean bill of health was used by the U.S. nuclear industry, which was at that time promoting nuclear energy as so healthy that radiation units were referred to as “units of sunshine.” Not until 1976 did Brookhaven formally acknowledge that it had been wrong in disregarding the information available from Utirik, where radiation exposure was less but where the proportion of thyroid cancers and malignancies was actually higher.

Bombing continued in the Marshalls until 1958. In 1967, the AEC told the Bikinians that they could return. From four to five million dollars was spent cleaning up the atoll; fifty thousand new trees were planted, and homes were built. In 1971, 150 islanders returned. Within one year, new studies of the islands’ radiation levels were requested, but not until 1978 was one done. That test confirmed that the Bikinians had been exposed to unacceptably high levels of contamination. The Bikinians left again, and the United States declared the island uninhabitable for at least another fifty years.

The Bikinians returned to the island of Kili, remaining dependent upon canned and packaged food from the United States and still wishing to return to their homeland. They own a trust fund of more than a million dollars in resettlement and compensation money, but that is nowhere near enough to restore their islands. Under the leadership of Mayor Tomaki Juda, son of the chief who ceded the Bikini Islands to the United States in 1946, they considered allowing one of the islands to be used as a nuclear waste repository, since it is already the most contaminated spot on Earth. Meanwhile, the Marshall Islanders experienced the symptoms of years of displacement as alcoholism, juvenile delinquency, and suicide, previously unknown in the culture, abounded.

Bravo provided the first opportunity for scientists to study the effects of radioactive fallout on a human population not affected by the actual explosion of a bomb. The initial data were skewed by the biases of the scientists involved, but by the late 1970’s, the data that emerged showed the seriousness of even middle and low doses of radiation. These data were used by antinuclear activists in the United States concerned about power plant safety and nuclear waste disposal sites. Bravo left behind a legacy of displaced islanders, of communities riddled with disease, and of islands contaminated for years to come. Although political and security factors dominated international efforts to achieve a ban on nuclear testing, gradually the environmental and health factors also gained wider notice. A partial nuclear test ban treaty was promulgated in 1963. Nuclear weapons;Bikini Atoll Bikini Atoll;nuclear bombing of Nuclear weapons;testing Bravo (nuclear bomb)

Further Reading
  • citation-type="booksimple"

    xlink:type="simple">Alcalay, Glenn H. “The Aftermath of Bikini.” Ecologist 10 (December, 1980): 346-351. A good short summary of the social and environmental situation of the atolls by an anthropologist who worked to gain compensation for the Bikini Islanders.
  • citation-type="booksimple"

    xlink:type="simple">Bertell, Rosalie. “The Marshallese.” In No Immediate Danger: Prognosis for a Radioactive Earth. Toronto, Ont.: Women’s Educational Press, 1985. An analysis of the nuclear industry by one who opposes it. The author, a senior cancer research scientist, acted as a consultant for the Citizens’ Advisory Committee on the Accident at Three Mile Island. A well-documented case, with footnotes and index.
  • citation-type="booksimple"

    xlink:type="simple">Davis, Jeffrey. “Bikini’s Silver Lining.” The New York Times Magazine, May 1, 1994, 47-73. An update on the Bikinians, focusing on the human story. Detailed but journalistic.
  • citation-type="booksimple"

    xlink:type="simple">Dibblin, Jane. Day of Two Suns: U.S. Nuclear Testing and the Pacific Islanders. New York: New Amsterdam Books, 1988. A journalistic account focusing on the experiences of the islanders effected. Very readable. Footnotes.
  • citation-type="booksimple"

    xlink:type="simple">Kiste, Robert C. The Bikinians: A Study in Forced Migration. Menlo Park, Calif.: Cummings, 1974. An anthropological examination of the effects of displacement on the Bikinians. Scholarly and detailed, with footnotes and bibliography.
  • citation-type="booksimple"

    xlink:type="simple">U.S. Congress. House Committee on Resources. The United States Nuclear Legacy in the Marshall Islands. Washington, D.C.: Government Printing Office, 2005. Official twenty-first century assessment of the U.S. government’s liability and obligations to the people of the Marshall Islands resulting from the Bikini Atoll nuclear tests. Bibliographic references.

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