Dr. Tsubokura's Radiation Lecture Vol.67
Author: Masaharu Tsubokura
Editors: Akihiko Ozaki M.D., Yuki Senoo
133. Radiation exposure caused by nuclear weapon testings
In the past, radiation exposure occurred on several occasions, including during the dropping of the atomic bombs on Hiroshima and Nagasaki during World War II, during atmospheric nuclear tests, and during accidents at nuclear processing facilities and nuclear power plants. In fact, Chernobyl, Three Mile Island, and the Fukushima Daiichi nuclear power plant are not the only nuclear power plants that had accidents involving nuclear reactors.
After World War II, atomic bombs and hydrogen bomb tests were conducted several times all over the world, including in the US, the former Soviet Union, and the UK. The number of nuclear tests carried out worldwide in 1958 reached 116, and in 1987, when the conflict and tension between the East and West rose due to the Cuban crisis, the annual number of nuclear tests conducted around the world increased to 178.
At that time, most nuclear tests were atmospheric tests. Therefore, radioactive substances that were spread in the air gradually fell to the ground over time, and this caused many people all over the world to be exposed to radiation exposure.
In 1963, the Partial Test Ban Treaty, a treaty that prohibited all test detonations of nuclear weapons except for those conducted underground, was signed by the governments of the former Soviet Union, the US, and the UK. Although this treaty was effective for preventing environmental pollution, it was not effective in nuclear disarmament, as nuclear tests conducted underground were still permitted. In addition, France and China refused to join this treaty, which was led by the US and Soviet Union government.
Since then, more than 2,000 nuclear weapon testings have been conducted throughout the world, with the ones conducted by the US and Soviet Union accounting for 80 percent of all tests. Furthermore, one-fourth of the tests were conducted in the atmosphere.
134. Thermonuclear bomb testings’ effect on remote islands
In the past, radiation exposure occurred on several occasions, including during the dropping of atomic bombs on Hiroshima and Nagasaki during World War II, during atmospheric nuclear tests, and during accidents at nuclear processing facilities and nuclear power plants.
The Republic of Marshall Islands in the Midwest Pacific and Micronesia lies along the coral reef, and its population is approximately 50,000. It was ruled by the Imperial Japanese government for 30 years after World War I, and after being defeated, it was taken over by the US government. During the US’s administration period, 66 nuclear weapon testings, of which 23 took place on the Bikini Atoll, were conducted on the Bikini and Eniwetok Atolls located in the Marshall Islands from 1946 to 1958.
Among them, the Bravo experiment conducted on the Bikini Atoll on March 1, 1954, is a well-known hydrogen bomb experiment.
The residents of the Bikini Atoll evacuated to nearby islands before the nuclear test began. However, the actual explosion was several times larger than predicted. As a result, the residents who evacuated the remote islands experienced radiation exposure. The experiment also involved Daigo Fukury? Maru, a tuna fishing boat operating 160 kilometers east of the hypocenter at that time.
The Japanese version of the manuscript was originally published in Fukushima Minyu, a local newspaper in Fukushima prefecture, Japan, on 30th July and 6th August 2017 was reproduced for MRIC Global under the author's permission.