Nuclear and radiation accidents and incidents
A nuclear and radiation accident is defined by the International Atomic Energy Agency (IAEA) as "an event that has led to significant consequences to people, the environment or the facility." Examples include lethal effects to individuals, large radioactivity release to the environment, or a reactor core melt.[6] The prime example of a "major nuclear accident" is one in which a reactor core is damaged and significant amounts of radioactive isotopes are released, such as in the Chernobyl disaster in 1986 and Fukushima nuclear disaster in 2011.[7]
The impact of nuclear accidents has been a topic of debate since the first nuclear reactors were constructed in 1954 and has been a key factor in public concern about nuclear facilities.[8] Technical measures to reduce the risk of accidents or to minimize the amount of radioactivity released to the environment have been adopted, however human error remains, and "there have been many accidents with varying impacts as well near misses and incidents".[8][9] As of 2014, there have been more than 100 serious nuclear accidents and incidents from the use of nuclear power. Fifty-seven accidents or severe incidents have occurred since the Chernobyl disaster, and about 60% of all nuclear-related accidents/severe incidents have occurred in the USA.[10] Serious nuclear power plant accidents include the Fukushima nuclear disaster (2011), the Chernobyl disaster (1986), the Three Mile Island accident (1979), and the SL-1 accident (1961).[11] Nuclear power accidents can involve loss of life and large monetary costs for remediation work.[12]
Nuclear submarine accidents include the K-19 (1961), K-11 (1965), K-27 (1968), K-140 (1968), K-429 (1970), K-222 (1980), and K-431 (1985)[11][13][14] accidents. Serious radiation incidents/accidents include the Kyshtym disaster, the Windscale fire, the radiotherapy accident in Costa Rica,[15] the radiotherapy accident in Zaragoza,[16] the radiation accident in Morocco,[17] the Goiania accident,[18] the radiation accident in Mexico City, the Samut Prakan radiation accident, and the Mayapuri radiological accident in India.[19]
The IAEA maintains a website reporting recent nuclear accidents.[20]
In 2020, the WHO stated that "Lessons learned from past radiological and nuclear accidents have demonstrated that the mental health and psychosocial consequences can outweigh the direct physical health impacts of radiation exposure."[21]"
Serious radiation and other accidents and incidents include:
For intentional or attempted theft of radioactive material, See Crimes involving radioactive substances#Intentional or attempted theft of radioactive material
The International Atomic Energy Agency says there is "a persistent problem with the illicit trafficking in nuclear and other radioactive materials, thefts, losses and other unauthorized activities".[109] The IAEA Illicit Nuclear Trafficking Database notes 1,266 incidents reported by 99 countries over the last 12 years, including 18 incidents involving HEU or plutonium trafficking:[110][90][111][112]
Ecological impacts[edit]
Impact on land[edit]
Isotopes released during a meltdown or related event are typically dispersed into the atmosphere and then settle on the surface through natural occurrences and deposition. Isotopes settling on the top soil layer can remain there for many years, due to their slow decay (long half-life). The long-term detrimental effects on agriculture, farming, and livestock, can potentially affect human health and safety long after the actual event.
After the Fukushima Daiichi accident in 2011, surrounding agricultural areas were contaminated with more than 100,000 MBq km−2 in cesium concentrations.[154] As a result, eastern Fukushima food production was severely limited. Due to Japan's topography and the local weather patterns, cesium deposits as well as other isotopes reside in top layer of soils all over eastern and northeastern Japan. Luckily, mountain ranges have shielded western Japan.
The Chernobyl disaster in 1986 exposed to radiation about 125,000 mi2 (320,000 km2) of land across Ukraine, Belarus, and Russia.[155] The amount of focused radiation caused severe damage to plant reproduction: most plants could not reproduce for at least three years. Many of these occurrences on land can be a result of the distribution of radioactive isotopes through water systems.