|Fig. 1: The Castle Bravo weapons test at Bikini Atoll. (Source: Wikimedia Commons)|
Nuclear weapons tests are necessary to gauge the safety, efficacy, and power of nuclear weapons. In an effort to avoid harming people, tests have traditionally been done in or above the atmosphere, underground, or underwater. According to the CDC, over 500 atmospheric nuclear weapon tests occurred between 1945 and 1980. 
Nuclear fallout and the radioactive contamination resulting from nuclear weaponry is incredibly harmful, particularly affecting biological organisms and their ecosystem. Due to the prolific number of nuclear weapons tested, the short- and long-term physiological effects on those who were exposed to radiation in weapons testing aftermath, as well as the direct effect on the environment, are of particular concern.
It is first worth noting the physiological effects of nuclear fallout. Fallout results from the soil mixing with radioactive fission products from the weapon.  Debris is carried by the wind, and eventually ends up back on earth.  Acute exposure to radiation may result in radiation sickness or death depending on the dosage, and frequently results in cancer.  Eye cataracts, hypertension, thyroid disease, and chronic liver disease have occurred in Japanese survivors of Hiroshima and Nagasaki with statistical significance.  A CDC-NCI study claims fallout resulting from nuclear weapons testing might have led to approximately 11,000 deaths, primarily caused by thyroid cancer from I-131 exposure. 
Castle Bravo marked the largest nuclear device detonated by the United States in 1954 in an attempt to test high-yield nuclear weapons (see Fig. 1).  Miscalculations about the yield of the device resulted in the largest U.S. nuclear contamination accident in Bikini Atoll, part of the Marshall Islands.  As a result of this miscalculation, nuclear fallout rained down on the inhabitants of the Marshall Islands.  Evacuations were slow, as only 167 Bikini Islanders were evacuated.  Inhabitants of the island experienced many of the serious health problems mentioned above as a result of the fallout. 
In 1954, the Soviet government conducted a nuclear weapons test in the village of Totskoye, near the Ural Mountains. A nuclear device comparable to that used in Hiroshima was dropped in an area close to tens of thousands of Soviet citizens, along with 45,000 Red Army troops.  Few villagers were evacuated, while those left were exposed to the nuclear fallout.  Residents were unaware of the horrors of radiation exposure.  The official purpose of the test was to determine if troops could fight in an area immediately after an atomic bomb was set off.  The soldiers were able to enter the affected area after the explosion, despite the temperature reaching 115 degrees from the fiery aftermath and smokey plumes. However, they, along with residents in nearby villages, suffered from long-term issues related to the fallout later on.  As a comparison for radiation exposure for the incident, the permitted exposure for United States troops was 5 roentgen a year, yet villagers and Red Army soldiers were exposed to 50 roentgen in tone incident. 
Due to numerous testing weapons testing incidents, sites have been critically contaminated both on land and in marine environments, e.g. the the atolls harmed by the Castle Bravo incident.  Many residents of Bikini Island became sick after they were told they could return in 1968.  Three families returned in 1972, but were forced to leave again after high levels of radiation were detected - nearly 8 years after the failed weapons test.  The islands became uninhabitable.
The spike in radiation levels from atmospheric tests of nuclear weapons is readily observed in nature.  Increased presence of radioactive isotopes released by nuclear weapons test are still found in test sites worldwide.  Radionuclides, such as Cs-137 and Sr-90, have been transferred to marine environments and affected local food chains in marine life as well.  Thyroid cancer occurrences have spiked in locations of atmospheric nuclear tests; U.S. nuclear tests conducted at the Nevada test sites caused contamination of the American population through rainfall runoff.  Radioactive soil contamination has also been recorded in nature as a result of these tests, as affected soil was discovered in Nevada, Utah, Colorado, Wyoming, and Northern Arizona near the Nevada test sites.  Consequentially, the spread of radionuclides through the food chain resulted in contaminated milk that reached human consumption, and is correlated with an increased rate of thyroid cancer in those states.  Additionally, underground tests still have potential dangers. Fission byproducts enter ecosystems via underground leakage. 
Radiation exposure also has serious impacts on plant life. It causes DNA damage and chromosomal aberrations, reduces seed germination, cause sterility or reproduction issues, and can kill plants.  The magnitude of damage depends on the amount of radiation exposure.
In 1987, the Nuclear Claims Tribunal was established in the United States with a $150 million trust for those affected by the Marshall incident.  By 2009, the Nuclear Claims Tribunal awarded more than $2 billion for injury, property loss, and class action claims resulting from nuclear incident aftermath.  Residents of Bikini Atoll have since filed claims for additional compensation but most of them have gone unanswered by the federal government. 
Compensation in other countries who participated in nuclear weapons testing varies widely. France did not begin offering compensation to victims of nuclear tests and their descendants until 2009. France had conducted many tests in the Sahara during the 1960s.  Veterans of the Christmas Islands nuclear tests, conducted by Britain, have received no such compensation.  Russia offered compensation to veterans who partook in the 1954 Totsk test, but no compensation was offered for civilians. 
In 1963, the United States entered its first nuclear treaty aimed at restricting the testing of nuclear weapons, with the exception of underground testing.  However, underground testing was banned as part of the Comprehensive Test Ban Treaty in 1996, of which 157 countries have since ratified the treaty.  President Bill Clinton signed the treaty, but the U.S. Congress did not agree to ratify it. 
© Christian Castellanos. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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