Three Mile Island accident health effects

Last updated

The effects of the 1979 Three Mile Island nuclear accident are widely agreed to be very low by scientists in the relevant fields. The American Nuclear Society concluded that average local radiation exposure was equivalent to a chest X-ray and maximum local exposure equivalent to less than a year's background radiation. [1] The U.S. BEIR report on the Biological Effects of Ionizing Radiation states that "the collective dose equivalent resulting from the radioactivity released in the Three Mile Island accident was so low that the estimated number of excess cancer cases to be expected, if any were to occur, would be negligible and undetectable." [2] A variety of epidemiology studies have concluded that the accident has had no observable long term health effects. [3] [4] [5] One dissenting study is "a re-evaluation of cancer incidence near the Three Mile Island nuclear plant" by Dr Steven Wing of the University of North Carolina. In this study, Dr Wing and his colleagues argue that earlier findings had "logical and methodological problems" and conclude that "cancer incidence, specifically lung cancer and leukemia, increased following the TMI accident in areas estimated to have been in the pathway of radioactive plumes than in other areas." [6] Other dissenting opinions can be found in the Radiation and Public Health Project, whose leader, Joseph Mangano, has questioned the safety of nuclear power since 1985. [7] [8] [9]

Contents

Initial investigations

In the aftermath of the accident, the investigations focused on the amounts of radioactivity released by the accident. American Nuclear Society explained using the official radioactivity emission figures that "the average radiation dose to people living within ten miles of the plant was eight millirem, and no more than 100 millirem to any single individual. Eight millirem is about equal to a chest X-ray, and 100 millirem is about a third of the average background level of radiation received by US residents in a year". [1] [10] To put this dose into context, while the average background radiation in the US is about 360 millirem per year, the Nuclear Regulatory Commission regulates all workers' of any US nuclear power plant exposure to radiation to a total of 5000 millirem per year. [11] Based on these low emission figures, early scientific publications on the health effects of the fallout estimated one or two additional cancer deaths in the 10-mile area around TMI. [8]

Worker overexposures

In the early days of the accident, three plant workers were known to have received extremity doses from entries into the Unit 2 auxiliary building. Ron Fountain, an auxiliary operator, hyperventilated while opening sample lines on March 28. [11] The following day, chemistry supervisor Ed Houser and radiation protection foreman Pete Velez received extremity doses while drawing a boron concentration sample from the health-physics lab inside the auxiliary building. [12]

Local resident reports

The official figures are too low to account for the acute health effects reported by some local residents and documented in two books; [12] [13] such health effects require exposure to at least 100,000 millirems (100 rems) to the whole body - 1000 times more than the official estimates. [14] The reported health effects are consistent with high doses of radiation, and comparable to the experiences of cancer patients undergoing radio-therapy [15] but have many other potential causes. [14] The effects included "metallic taste, erythema, nausea, vomiting, diarrhea, hair loss, deaths of pets, farm and wild animals, and damage to plants." [16] Some local statistics showed dramatic one-year changes among the most vulnerable: "in Dauphin County, where the Three Mile Island plant is located, the 1979 death rate among infants under one year represented a 28 percent increase over that of 1978, and among infants under one month, the death rate increased by 54 percent." [8] Physicist Ernest Sternglass, a specialist in low-level radiation, noted these statistics in the 1981 edition of his book Secret Fallout: low-level radiation from Hiroshima to Three-Mile Island. In their final 1981 report, however, the Pennsylvania Department of Health, examining death rates within the 10-mile area around TMI for the 6 months after the accident, said that the TMI-2 accident did not cause local deaths of infants or fetuses. [17] [18]

Scientific work continued in the 1980s, but focused heavily on the mental health effects due to stress, [8] as the Kemeny Commission had concluded that this was the sole public health effect. [19] A 1984 survey by a local psychologist of 450 local residents, documenting acute radiation health effects (as well as 19 cancers 1980-84 amongst the residents against an expected 2.6 [16] ), ultimately led the TMI Public Health Fund reviewing the data [20] and supporting a comprehensive epidemiological study by a team at Columbia University. [15]

Columbia epidemiological study

In 1990-1 a Columbia University team, led by Maureen Hatch, carried out the first epidemiological study on local death rates before and after the accident, for the period 1975-1985, for the 10-mile area around TMI. [3] [19] Assigning fallout impact based on winds on the morning of March 28, 1979, [3] the study found no link between fallout and cancer risk. [8] The study found that cancer rates near the Three Mile Island plant peaked in 1982-3, but their mathematical model did not account for the observed increase in cancer rates, since they argued that latency periods for cancer are much longer than three years. From 1975 to 1979 there were 1,722 reported cases of cancer, and between 1981 and 1985 there were 2,831, signifying a 64 percent increase after the meltdown. [21] The study concludes that stress may have been a factor (though no specific biological mechanism was identified), and speculated that changes in cancer screening were more important. [19]

Wing review

Subsequently, lawyers for 2000 residents asked epidemiologist Stephen Wing of the University of North Carolina at Chapel Hill, a specialist in nuclear radiation exposure, to re-examine the Columbia study. Wing was reluctant to get involved, later writing that "allegations of high radiation doses at TMI were considered by mainstream radiation scientists to be a product of radiation phobia or efforts to extort money from a blameless industry." [16] Wing later noted that in order to obtain the relevant data, the Columbia study had to submit to what Wing called "a manipulation of research" in the form of a court order which prohibited "upper limit or worst case estimates of releases of radioactivity or population doses... [unless] such estimates would lead to a mathematical projection of less than 0.01 health effects." [16] Wing found cancer rates raised within a 10-mile radius two years after the accident by 0.034% +/- 0.013%, 0.103% +/- 0.035%, and 0.139% +/- 0.073% for all cancer, lung cancer, and leukemia, respectively. [6] An exchange of published responses between Wing and the Columbia team followed. [8] Wing later noted a range of studies showing latency periods for cancer from radiation exposure between 1 and 5 years due to immune system suppression. [16] Latencies between 1 and 9 years have been studied in a variety of contexts ranging from the Hiroshima survivors and the fallout from Chernobyl to therapeutic radiation; a 5-10 year latency is most common. [22]

Further studies

On the recommendation of the Columbia team, the TMI Public Health Fund followed up its work with a longitudinal study. [23] The 2000-3 University of Pittsburgh study [24] compared post-TMI death rates in different parts of the local area, again using the wind direction on the morning of 28 March to assign fallout impact, In contrast to the Columbia study, which estimated exposure in 69 areas, the Pittsburgh study drew on the TMI Population Registry, compiled by the Pennsylvania Department of Health. This was based on radiation exposure information on 93% of the population living within five miles of the nuclear plant - nearly 36,000 people, gathered in door-to-door surveys shortly after the accident. [25] The study found slight increases in cancer and mortality rates but "no consistent evidence" of causation by TMI. [24] Wing et al. criticized the Pittsburgh study for making the same assumption as Columbia: that the official statistics on low doses of radiation were correct - leading to a study "in which the null hypothesis cannot be rejected due to a priori assumptions." [26] Hatch et al. noted that their assumption had been backed up by dosimeter data, [23] though Wing et al. noted the incompleteness of this data, particularly for releases early on. [27]

In 2005 R. William Field, an epidemiologist at the University of Iowa, who first described radioactive contamination of the wild food chain from the accident[ citation needed ] suggested that some of the increased cancer rates noted around TMI were related to the area's very high levels of natural radon, noting that according to a 1994 EPA study, the Pennsylvania counties around TMI have the highest regional screening radon concentrations in the 38 states surveyed. [28] The factor had also been considered by the Pittsburgh study [24] and by the Columbia team, which had noted that "rates of childhood leukemia in the Three Mile Island area are low compared with national and regional rates." [3] A 2006 study on the standard mortality rate in children in 34 counties downwind of TMI found an increase in the rate (for cancers other than leukemia) from 0.83 (1979–83) to 1.17 (1984–88), meaning a rise from below the national average to above it. [22]

A paper in 2008 studying thyroid cancer in the region found rates as expected in the county in which the reactor is located, and significantly higher than expected rates in two neighboring counties beginning in 1990 and 1995 respectively. The research notes that "These findings, however, do not provide a causal link to the TMI accident." [29] According to Joseph Mangano (who is a member of The Radiation and Public Health Project, an organization with little credibility amongst epidemiologists, [30] ) three large gaps in the literature include: no study has focused on infant mortality data, or on data from outside the 10-mile zone, or on radioisotopes other than iodine, krypton, and xenon. [8]

Related Research Articles

Background radiation is a measure of the level of ionizing radiation present in the environment at a particular location which is not due to deliberate introduction of radiation sources.

<span class="mw-page-title-main">Nuclear fallout</span> Residual radioactive material following a nuclear blast

Nuclear fallout is the residual radioactive material propelled into the upper atmosphere following a nuclear blast, so called because it "falls out" of the sky after the explosion and the shock wave has passed. It commonly refers to the radioactive dust and ash created when a nuclear weapon explodes. The amount and spread of fallout is a product of the size of the weapon and the altitude at which it is detonated. Fallout may get entrained with the products of a pyrocumulus cloud and fall as black rain. This radioactive dust, usually consisting of fission products mixed with bystanding atoms that are neutron-activated by exposure, is a form of radioactive contamination.

<span class="mw-page-title-main">Three Mile Island accident</span> 1979 nuclear accident in Pennsylvania

The Three Mile Island accident was a partial nuclear meltdown of the Unit 2 reactor (TMI-2) of the Three Mile Island Nuclear Generating Station on the Susquehanna River in Londonderry Township, near Harrisburg, Pennsylvania. The reactor accident began at 4:00 a.m. on March 28, 1979, and released radioactive gases and radioactive iodine into the environment. It is the worst accident in U.S. commercial nuclear power plant history. On the seven-point logarithmic International Nuclear Event Scale, the TMI-2 reactor accident is rated Level 5, an "Accident with Wider Consequences".

The roentgen equivalent man (rem) is a CGS unit of equivalent dose, effective dose, and committed dose, which are dose measures used to estimate potential health effects of low levels of ionizing radiation on the human body.

<span class="mw-page-title-main">Potassium iodide</span> Ionic compound (KI)

Potassium iodide is a chemical compound, medication, and dietary supplement. It is a medication used for treating hyperthyroidism, in radiation emergencies, and for protecting the thyroid gland when certain types of radiopharmaceuticals are used. In the third world it is also used for treating skin sporotrichosis and phycomycosis. It is a supplement used by people with low dietary intake of iodine. It is administered orally.

<span class="mw-page-title-main">Linear no-threshold model</span> Deprecated model predicting health effects of radiation

The linear no-threshold model (LNT) is a dose-response model used in radiation protection to estimate stochastic health effects such as radiation-induced cancer, genetic mutations and teratogenic effects on the human body due to exposure to ionizing radiation. The model assumes a linear relationship between dose and health effects, even for very low doses where biological effects are more difficult to observe. The LNT model implies that all exposure to ionizing radiation is harmful, regardless of how low the dose is, and that the effect is cumulative over lifetime.

<span class="mw-page-title-main">Radiation hormesis</span> Hypothesis regarding low doses of ionizing radiation on health

Radiation hormesis is the hypothesis that low doses of ionizing radiation are beneficial, stimulating the activation of repair mechanisms that protect against disease, that are not activated in absence of ionizing radiation. The reserve repair mechanisms are hypothesized to be sufficiently effective when stimulated as to not only cancel the detrimental effects of ionizing radiation but also inhibit disease not related to radiation exposure. It has been a mainstream concept since at least 2009.

<span class="mw-page-title-main">Three Mile Island Nuclear Generating Station</span> Closed nuclear power plant in Pennsylvania, United States

Three Mile Island Nuclear Generating Station is a closed nuclear power plant on Three Mile Island in Pennsylvania on the Susquehanna River just south of Harrisburg. It has two separate units, TMI-1 and TMI-2.

Downwinders were individuals and communities in the intermountain West between the Cascade and Rocky Mountain ranges primarily in Arizona, Nevada, New Mexico, and Utah but also in Oregon, Washington, and Idaho who were exposed to radioactive contamination or nuclear fallout from atmospheric or underground nuclear weapons testing, and nuclear accidents.

<span class="mw-page-title-main">Effects of the Chernobyl disaster</span> Assessment of Chernobyls impact on Earth since 1986

The 1986 Chernobyl disaster triggered the release of radioactive contamination into the atmosphere in the form of both particulate and gaseous radioisotopes. As of 2024, it was the world's largest known release of radioactivity into the environment.

Ernest Joachim Sternglass was a professor emeritus at the University of Pittsburgh and director of the Radiation and Public Health Project. He was an American physicist and author, best known for his controversial research on the health risks of low-level radiation from atmospheric testing of nuclear weapons and from nuclear power plants.

<span class="mw-page-title-main">Comparison of Chernobyl and other radioactivity releases</span>

This article compares the radioactivity release and decay from the Chernobyl disaster with various other events which involved a release of uncontrolled radioactivity.

<span class="mw-page-title-main">Environmental impact of nuclear power</span>

Nuclear power has various environmental impacts, both positive and negative, including the construction and operation of the plant, the nuclear fuel cycle, and the effects of nuclear accidents. Nuclear power plants do not burn fossil fuels and so do not directly emit carbon dioxide. The carbon dioxide emitted during mining, enrichment, fabrication and transport of fuel is small when compared with the carbon dioxide emitted by fossil fuels of similar energy yield, however, these plants still produce other environmentally damaging wastes. Nuclear energy and renewable energy have reduced environmental costs by decreasing CO2 emissions resulting from energy consumption.

<span class="mw-page-title-main">Effects of nuclear explosions on human health</span> Wissenschaftlicher Artikel

The medical effects of the atomic bomb upon humans can be put into the four categories below, with the effects of larger thermonuclear weapons producing blast and thermal effects so large that there would be a negligible number of survivors close enough to the center of the blast who would experience prompt/acute radiation effects, which were observed after the 16 kiloton yield Hiroshima bomb, due to its relatively low yield:

Radiation and Public Health Project (RPHP) is a nonprofit educational and scientific organization founded in 1985 by Jay M. Gould, a statistician and epidemiologist, Benjamin A. Goldman, and Ernest Sternglass. The "shoestring organization" with "offices mainly on [Joseph J. Mangano's] kitchen table" was established to examine the relationships between low-level nuclear radiation and public health and question the safety of nuclear power.

Exposure to ionizing radiation is known to increase the future incidence of cancer, particularly leukemia. The mechanism by which this occurs is well understood, but quantitative models predicting the level of risk remain controversial. The most widely accepted model posits that the incidence of cancers due to ionizing radiation increases linearly with effective radiation dose at a rate of 5.5% per sievert; if correct, natural background radiation is the most hazardous source of radiation to general public health, followed by medical imaging as a close second. Additionally, the vast majority of non-invasive cancers are non-melanoma skin cancers caused by ultraviolet radiation. Non-ionizing radio frequency radiation from mobile phones, electric power transmission, and other similar sources have been investigated as a possible carcinogen by the WHO's International Agency for Research on Cancer, but to date, no evidence of this has been observed.

<span class="mw-page-title-main">Fukushima nuclear accident casualties</span> Possible casualties and related deaths caused by the Fukushima nuclear disaster

The Fukushima Daiichi nuclear accident genshiryoku hatsudensho jiko) was a series of equipment failures, nuclear meltdowns, and releases of radioactive materials at the Fukushima I Nuclear Power Plant, following the Tōhoku earthquake and tsunami on 11 March 2011. It was the largest nuclear disaster since the Chernobyl disaster of 1986, and the radiation released exceeded official safety guidelines. Despite this, there were no deaths caused by acute radiation syndrome. Given the uncertain health effects of low-dose radiation, cancer deaths cannot be ruled out. However, studies by the World Health Organization and Tokyo University have shown that no discernible increase in the rate of cancer deaths is expected. Predicted future cancer deaths due to accumulated radiation exposures in the population living near Fukushima have ranged in the academic literature from none to hundreds.

<span class="mw-page-title-main">Nuclear labor issues</span> Radiation workers health and labor issues

Nuclear labor issues exist within the international nuclear power industry and the nuclear weapons production sector worldwide, impacting upon the lives and health of laborers, itinerant workers and their families.

<span class="mw-page-title-main">Radiation exposure</span> Measure of ionization of air by ionizing radiation

Radiation exposure is a measure of the ionization of air due to ionizing radiation from photons. It is defined as the electric charge freed by such radiation in a specified volume of air divided by the mass of that air. As of 2007, "medical radiation exposure" was defined by the International Commission on Radiological Protection as exposure incurred by people as part of their own medical or dental diagnosis or treatment; by persons, other than those occupationally exposed, knowingly, while voluntarily helping in the support and comfort of patients; and by volunteers in a programme of biomedical research involving their exposure. Common medical tests and treatments involving radiation include X-rays, CT scans, mammography, lung ventilation and perfusion scans, bone scans, cardiac perfusion scan, angiography, radiation therapy, and more. Each type of test carries its own amount of radiation exposure. There are two general categories of adverse health effects caused by radiation exposure: deterministic effects and stochastic effects. Deterministic effects are due to the killing/malfunction of cells following high doses; and stochastic effects involve either cancer development in exposed individuals caused by mutation of somatic cells, or heritable disease in their offspring from mutation of reproductive (germ) cells.

References

  1. 1 2 "What Happened and What Didn't in the TMI-2 Accident". American Nuclear Society. Archived from the original on 2011-07-17. Retrieved 2008-11-09.
  2. ↑ National Research Council (US) Committee on the Biological Effects of Ionizing Radiation (1990). Health effects of exposure to low levels of ionizing radiation (BEIR V). Washington, DC: National Academies Press. p. 377. ISBN   978-0-309-03995-6. PMID   25032334.{{cite book}}: |website= ignored (help)
  3. 1 2 3 4 Maureen C. Hatch; et al. (1990). "Cancer near the Three Mile Island Nuclear Plant: Radiation Emissions". American Journal of Epidemiology. 132 (3). Oxford Journals: 397–412. doi: 10.1093/oxfordjournals.aje.a115673 . PMID   2389745.
  4. ↑ Hatch MC, Wallenstein S, Beyea J, Nieves JW, Susser M; Wallenstein; Beyea; Nieves; Susser (June 1991). "Cancer rates after the Three Mile Island nuclear accident and proximity of residence to the plant". American Journal of Public Health. 81 (6): 719–724. doi:10.2105/AJPH.81.6.719. PMC   1405170 . PMID   2029040.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. ↑ R. J. Levin (2008), "Incidence of thyroid cancer in residents surrounding the three-mile island nuclear facility", Laryngoscope 118 (4), pp. 618–628 "These findings, however, do not provide a causal link to the TMI accident."
  6. 1 2 Wing, Steve; Richardson, David; Armstrong, Donna; Crawford, Douglas (January 1997). "A reevaluation of cancer incidence near the Three Mile Island nuclear plant: The collision of evidence and assumptions". Environmental Health Perspectives. 105 (1): 52–57. doi:10.1289/ehp.9710552. JSTOR   3433062. PMC   1469835 . PMID   9074881.
  7. ↑ Newman, Andy (November 11, 2003). "In Baby Teeth, a Test of Fallout; A Long-Shot Search for Nuclear Peril in Molars and Cuspids". The New York Times.
  8. 1 2 3 4 5 6 7 Mangano, Joseph (2004), "Three Mile Island: Health study meltdown", Bulletin of the atomic scientists, 60(5), pp.31-35
  9. ↑ Fecht, Sarah (2004-04-08). "What Can We Do About Junk Science?". Popular Mechanics. Retrieved 2020-05-29.
  10. ↑ "Three-Mile Island cancer rates probed". BBC News. 2002-11-01. Retrieved 2008-11-25.
  11. 1 2 "NRC: Fact Sheet on Biological Effects of Radiation" . Retrieved 2008-12-29.
  12. 1 2 Katagiri Mitsuru and Aileen M. Smith (1989), Three Mile Island: The People's Testament - based on interviews with 250 residents between 1979 and 1988.
  13. ↑ Robert Del Tredici (1982) The People of Three Mile Island, Random House, Inc.
  14. 1 2 GPU Utilities 91986), "Radiation And Health Effects: A Report on the TMI-2 Accident and Related Health Studies" [usurped]
  15. 1 2 Sue Sturgis (2009) "FOOLING WITH DISASTER? Startling revelations about Three Mile Island disaster raise doubts over nuclear plant safety" Archived 2010-04-18 at the Wayback Machine , Facing South: Online Magazine of the Institute for Southern Studies, April 2009
  16. 1 2 3 4 5 Wing, Steven (2003) "Objectivity and Ethics in Environmental Health Science", Environmental Health Perspectives Volume 111, Number 14, November 2003
  17. ↑ "Report doubts infant death rise from three mile island mishap". The New York Times . 1981-03-21. Retrieved 2008-12-29.
  18. ↑ Walker, p234
  19. 1 2 3 Hatch MC, Wallenstein S, Beyea J, Nieves JW, Susser M (June 1991). "Cancer rates after the Three Mile Island nuclear accident and proximity of residence to the plant". American Journal of Public Health. 81 (6): 719–724. doi:10.2105/AJPH.81.6.719. PMC   1405170 . PMID   2029040.
  20. ↑ Moholdt B. Summary of acute symptoms by TMI area residents during accident. In:Proceedings of the workshop on Three Mile Island dosimetry. Philadelphia:Academy of Natural Sciences, 1985.
  21. ↑ Mangano, Joseph. "Three Mile Island: Health Study Meltdown". Bulletin of the Atomic Scientists. Retrieved 1 May 2014.
  22. 1 2 Mangano, Joseph (2006), "A short latency between radiation exposure from nuclear plants and cancer in young children", International journal of health services, vol:36 iss:1 pg:113-135
  23. 1 2 Hatch; et al. (1997). "Comments on "A Re-Evaluation of Cancer Incidence Near the Three Mile Island Nuclear Plant". Environmental Health Perspectives. 105 (1): 1. doi:10.1289/ehp.9710512. PMC   1469856 . PMID   9074862.
  24. 1 2 3 Talbott Evelyn O.; et al. (2000). "Mortality Among the Residents of the Three Mile Accident Area: 1979–1992". Environmental Health Perspectives. 108 (6): 545–52. doi:10.1289/ehp.00108545. PMC   1638153 . PMID   10856029.; Talbott Evelyn O.; et al. (2003). "Long-Term Follow-up of the Residents of the Three Mile Island Accident". Environmental Health Perspectives. 111 (3): 341–48. doi:10.1289/ehp.5662. PMC   1241392 . PMID   12611664.
  25. ↑ Holzman (2003), "Cancer and three mile island", Environmental health perspectives, vol:111 iss:3 pg:A166 -A167
  26. ↑ Wing, S. and Richardson, D. (2000), "Collision of Evidence and Assumptions: TMI Déjà View", Environmental Health Perspectives, 108(12), December 2000
  27. ↑ Wing, S.; Richardson, D.; Armstrong, D. (1997). "Reply to Comments on "A Reevaluation of Cancer Incidence near the Three Mile Island"". Environmental Health Perspectives. 105 (3): 266–268. doi:10.2307/3433255. JSTOR   3433255. PMC   1469992 . PMID   9171981.
  28. ↑ R. W. Field (2005), "Three Mile Island epidemiologic radiation dose assessment revisited: 25 years after the accident", Radiation Protection Dosimetry 113 (2), pp. 214-217
  29. ↑ RJ Levin (2008), "Incidence of thyroid cancer in residents surrounding the three mile island nuclear facility", Laryngoscope 118 (4), pp. 618-628
  30. ↑ Newman, Andy (2003-11-11). "In Baby Teeth, a Test of Fallout; A Long-Shot Search for Nuclear Peril in Molars and Cuspids". The New York Times.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.