||The examples and perspective in this article may not represent a worldwide view of the subject. (July 2010)|
Downwinders refers to individuals and communities who are exposed to radioactive contamination or nuclear fallout from atmospheric or underground nuclear weapons testing, and nuclear accidents. Currently, this article focuses on incidents in the United States, or caused by its weapons testing.
More generally, the term can also include those communities and individuals who are exposed to ionizing radiation and other emissions due to the regular production and maintenance of nuclear weapons, nuclear power, and nuclear waste. In regions near U.S. nuclear sites, downwinders may be exposed to releases of radioactive materials into the environment that contaminate their groundwater systems, food chains, and the air they breathe. Some downwinders may have suffered acute exposure due to their involvement in uranium mining and nuclear experimentation.
Several severe adverse health effects, such as an increased incidence of cancers, non-cancerous thyroid diseases, and congenital malformations have been observed in many and diverse "downwind" communities exposed to nuclear fallout and radioactive contamination. The impact of nuclear contamination on an individual is generally estimated as the result of the dose of radiation received and the duration of exposure, using the Linear No-Threshold Model (LNT). Sex, age, race, culture, occupation, class, location, and simultaneous exposure to additional environmental toxins are also significant, but often overlooked, factors that contribute to the health effects on a particular "downwind" community.
Downwinders and nuclear testing 
Between 1945 and 1980, the United States, U.S.S.R, United Kingdom, France and China exploded 504 nuclear devices in atmospheric tests at thirteen primary sites yielding the explosive equivalent of 440 megatons of TNT. Of these atmospheric tests, 330 were conducted by the United States. Accounting for all types of nuclear tests, official counts show that the United States has conducted 1,054 nuclear weapons tests to date, involving at least 1,151 nuclear devices, most of which occurred at Nevada Test Site and the Pacific Proving Grounds in the Marshall Islands, with ten other tests taking place at various locations in the United States, including Alaska, Colorado, Mississippi, and New Mexico. There have been an estimated 2,000 nuclear tests conducted worldwide; the number of nuclear tests conducted by the United States alone is currently more than the sum of nuclear testing done by all other known nuclear states (USSR, Great Britain, France, China, India, Pakistan, North Korea) combined.
These nuclear tests infused vast quantities of radioactive material into the world’s atmosphere, which was widely dispersed and then deposited as global fallout.
How downwinders are exposed to fallout 
The nuclear explosions produce a characteristic mushroom cloud, which moves downwind as it reaches its stabilization height. Dispersion of the radioactive elements causes vertical and lateral cloud movement, spreading radioactive materials over adjacent regions. While the large particles settle nearby the site of the detonation, smaller particles and gases may be dispersed around the world. Additionally, some explosions injected radioactive material into the stratosphere, more than 10 kilometers above ground-level, meaning it may float there for years before being subsequently deposited uniformly around the earth. Global fallout is the result, which exposes everything to an elevated level of man-made background radiation. While "downwinders" refers to those who live and work closest to the explosion site and are thus most acutely affected, there is a global effect of increased health risks due to ionizing radiation in the atmosphere.
Health effects of nuclear testing 
The earliest concerns raised about the health effects of exposure to nuclear fallout had to do with fears of genetic alterations that may occur among the offspring of those most exposed. However, the observed inheritable effects of radiation exposure by groups with histories of acute risk are considered minimal compared with the significant increase in thyroid cancer, leukemia and certain solid tumors that have developed within a decade or more after exposure. As studies of biological samples (including bone, thyroid glands and other tissues) have been undertaken, it has become increasingly clear that specific radionuclides in fallout are implicated in fallout-related cancers and other late effects.
In 1980, People magazine revealed some consequences of continental nuclear testing for American citizens. The magazine disclosed that of some 220 cast and crew who filmed a 1956 film, The Conqueror, on location near St. George, Utah, ninety-one had come down with cancer, with an unheard of 41 per cent morbidity rate. Of these, forty-six had died of cancer by 1980. Among the victims were John Wayne and Susan Hayward, the stars of the film.
Current status of U.S. nuclear testing 
After adopting the Comprehensive Test Ban Treaty in 1996, the U.S. and several other nuclear states pledged to stop nuclear testing. However, as of early 2011, the United States has failed to ratify the Comprehensive Test Ban Treaty.
Specific test sites 
From 1951 – mid-1962, the Nevada Test Site (NTS) was a primary site used for both surface and above-ground nuclear testing, with 86 tests at or above ground level, and 14 other tests underground, all of which involved releases of significant amounts of radioactive material into the atmosphere.
In the 1950s, people who lived in the vicinity of the NTS were encouraged to sit outside and watch the mushroom clouds that were created by nuclear bomb explosions. Many were given radiation badges to wear on their clothes, which were later collected by the Atomic Energy Commission to gather data about radiation levels.
In a report by the National Cancer Institute, released in 1997, it was determined that the nearly ninety atmospheric tests at the Nevada Test Site (NTS) left high levels of radioactive iodine-131 (5.5 exabecquerels) across a large area of the continental United States, especially in the years 1952, 1953, 1955, and 1957. The National Cancer Institute report estimates that doses received in these years are estimated to be large enough to produce 10,000 to 75,000 additional cases of thyroid cancer in the U.S. Another report, published by the Scientific Research Society, estimates that about 22,000 additional radiation-related cancers and 2,000 additional deaths from radiation-related leukemia are expected to occur in the United States because of external and internal radiation from both NTS and global fallout.
The threat of downwind exposure to radioactivity remaining at the Nevada Test Site from nuclear weapons tests was still an issue as late as 2007. The Pentagon planned to test a 700-ton ammonium nitrate-and-fuel oil "bunker buster" weapon. The planned "Divine Strake" test would have raised a large mushroom cloud of contaminated dust that could have blown toward population centers such as Las Vegas, Boise, Salt Lake City, and St. George, Utah. This project was cancelled in February 2007, in large part due to political pressure inspired by the threat of downwind exposure to radioactivity.
While many downwinders were exposed to weapons testing, millions more have been affected by radioactive fallout due to U.S. sites engaged in the production of nuclear weapons and/or nuclear power. For example, Hanford is a former nuclear weapons production site located in south central Washington state, where the Washington state Department of Health collaborated with the citizen-led Hanford Health Information Network (HHIN) to publicize significant data about the health effects of Hanford’s operations. Established in 1943, Hanford released radioactive materials into the air, water and soil, releases which largely resulted form the routine site’s operation, though some were also due to accidents and intentional releases. Those who lived downwind from Hanford or who used the Columbia River downstream from Hanford were all exposed to elevated doses of radiation, which are presumed to have caused increased incidents of health problems and birth defects that generated widespread public concern over the public and environmental health implications of the site.
By February 1986, mounting citizen pressure forced the U.S. Department of Energy to release to the public 19,000 pages of previously unavailable historical documents about Hanford’s operations. These reports revealed there had been huge releases of radioactive materials into the environment that contaminated the Columbia River and more than 75,000 square miles (190,000 km2) of land. In particular, it made clear downwinders' exposure to plutonium, which was produced in nuclear reactors along the Columbia River. The reactors used large amounts of water from the river for cooling, which caused materials in the river water to become radioactive as they passed through the reactor. The water and the radioactive materials it contained were released into the river after passing through the reactors, thus contaminating the both groundwater systems and aquatic animals downstream as far West as the Washington and Oregon coasts.
A class-action lawsuit brought by two thousand Hanford downwinders against the federal government has been in the court system for many years. The first six plaintiffs went to trial in 2005, in a bellwether trial to test the legal issues applying to the remaining plaintiffs in the suit.
Plutonium was also separated and purified for use in nuclear weapons, which resulted in the release of radioactive material into the air. Air polluted by material from the Hanford site traveled throughout Washington, Oregon, Idaho, Montana, and even into Canada. Further contamination filtered into the food chain via contaminated fields where milk cows grazed; hazardous fallout was ingested by communities who consumed the radioactive food and drank the milk. Another source of contaminated food came from Columbia River fish; their impact was disproportionately felt by Native American communities who depended on the river for their customary diets. The estimate of those exposed to radioactive contamination due to living downwind of Hanford or ingesting food or water that flowed downstream is as high as 2 million.
Marshall Islands 
While the term "downwinders" generally connotes nuclear fallout victims based in the continental U.S. near sites such as Hanford and NTS, the population of the Marshall Islands bore a large brunt of nuclear testing under the United States' "Pacific Proving Ground" program. Now known officially as the Republic of the Marshall Islands, it was an occupied territory of the United States from 1944–1979, years during which the United States tested 66 nuclear weapons in the Marshall Islands.
One of these many tests, the March 1, 1954 explosion of Castle Bravo, a U.S. thermonuclear device, was responsible for most of the vast radiation exposure endured by the local population. The fallout-related doses of this single test are believed[who?] to be the highest recorded in the history of worldwide nuclear testing. Many of the Marshall Islands which were part of the Pacific Proving Grounds remain contaminated by nuclear fallout, and many of those downwinders who were living on the islands at the time of testing have suffered from a highly increased incidence of several types of cancers and birth defects.
Effects of radiation on female downwinders 
The primary long-term health hazard associated with exposure to ionizing radiation as a result of nuclear fallout is an increased risk for cancers of the thyroid, other solid tumor cancers, and leukemia. The relationship between radiation exposure and subsequent cancer risk is considered "the best understood, and certainly the most highly quantified, dose-response relationship for any common environmental human carcinogen", according to report by the National Cancer Institute. While men in the United States account for 22 percent more cases of cancer than women, the carcinogenic effects of radiation are much higher in women than in men. In recent years, studies conducted by both the National Research Council and the EPA have confirmed that compared to men, women are at a significantly higher risk of radiation-induced cancers, such and that women’s sensitivity to radiation-induced cancers is much higher than was previously estimated. The increased radiosensitivity of certain organs in women, such as the breast, ovaries, and thyroid is likely the cause of this difference.
In the EPA’s 1999 Federal Guidance Report #13(FGR 13), Cancer Risk Coefficients for Environmental Exposure to Radionuclides, the authors conclude that women have a 48 percent higher radionuclide-related cancer mortality risk than men. Further evidence of sex-based disparities in radiation-induced cancers was published in the 2006 report by the National Research Council’s Committee to Assess Health Risks from Exposure to Low Levels of Ionizing Radiation (known as the BEIR VII report), which found that women’s risk due to radiation exposure exceeded men’s by 37.5 percent. When one considers rates of cancer incidence separately from rates of cancer fatality, the sex disparities are even greater. The BEIR VII Committee concluded that, given the same level of radiation exposure, women are 52 percent more likely than men to develop cancer, while the EPA report puts the estimate of difference as high as 58 percent.
The differences in risk are even greater when considering organ-specific cancers, especially given that both reports identify breast, ovarian, lung, colon, and thyroid tissues as the most radiosensitive among women. For example, the FGR 13 has estimated that the ratio of thyroid cancer incidence for women as compared to men is 2.14, while the findings of BEIR VII suggest that women are even more vulnerable to radiation-induced thyroid cancer at a ratio of 4.76.
As increasing concerns are raised regarding the environmental risks related to breast, it is interesting to note that the BEIR VII report cited evidence that suggests that "radiation may interact synergistically with other risk factors for breast cancer", raising the possibility that endocrine disrupting chemicals like PCBs and dioxins might combine to increase the risks associated with radiation beyond that which would be caused by either separately. A related concern is that radionuclides that may be passed through the breast milk, causing some women who are downwinders to be understandably reluctant to breastfeed their children. While reducing the radioactive intake of their infants is an important preventative measure, it denies women the opportunity to engage a preventative measure for their own health; i.e. breastfeeding has been widely documented as a practice that can reduce women's risk of developing breast cancer. By refraining from breastfeeding, women downwinders' risks of breast cancer incidence becomes even more elevated.
Pregnancy and birth outcomes 
Mounting research indicates that above certain levels of radiation, a miscarriage will result. Whether there is a determining threshold or whether other factors may make some women more vulnerable to radiation-induced miscarriage has not yet been determined. However, it is clear from studies of nuclear bomb and test site survivors that fetal malformations are a special risk if a woman is exposed to high doses of nuclear-related radiation in early pregnancy, when organs are being formed. The impact of a miscarriage, threatened pregnancy, or congenital disorder on a mother is considerable, affecting not only her physical, sexual, and reproductive health, but her social and emotional wellness, as well. The effects of radiation on fetal formation are also uniquely a women's health issue to the extent that female fetuses' ova are formed while they are still in utero; adverse effects on a mother carrying a female fetus pose multigenerational effects and may increase the daughter's risks for ovarian cancer, infertility, and other reproductive developmental problems.
Under the Radiation Exposure Compensation Act of 1990, downwinders who are able to show correlations between certain diseases and their personal exposure to nuclear fallout are eligible for $50,000 in compensation from the federal government. Uranium miners are eligible for $100,000, and onsite participants are eligible for $75,000. However, there are particular obstacles to receiving needed health care and compensation faced by many widows of Navajo uranium miners, who were affected by disproportionately high incidences of fatal lung cancer. One problem for Navajo widows seeking the federal benefits for which they are qualified is the requirement that they document their marriages, although many were married in the 1930s and 1940s in undocumented tribal ceremonies. Language and cultural barriers pose further obstacles to Navajo downwinders; since many elderly Navajos do not speak English, their children bear the responsibility to do the research and procure from a tribal law judge a validation certificate of their tribal marriage. Similarly, it is difficult to access the outdated medical and occupational documentation that the government required even though the government's and uranium companies' own records for Navajo miners are sparse and difficult to access.
See also 
- Chernobyl disaster
- New Zealand's nuclear-free zone
- Project 4.1
- Windscale fire
- Atomic veteran
- The Plutonium Files
- Simon, Steven L. “Radiation Doses To Local Populations Near Nuclear Weapons Test Sites Worldwide,” Health Physics. 82(5):706-725, May 2002
- Dr. Arjun Mahkijani, "Science for the Vulnerable: Setting Radiation and Multiple Exposure Environmental Health Standards to Protect Those Most at Risk," October 19, 2006: http://www.ieer.org/campaign/report.pdf
- Gallery of U.S. Nuclear Tests
- Simon, Steven L., André Bouville and Charles E. Land, “Fallout from Nuclear Weapons Tests and Cancer Risks,” American Scientist, vol. 94 (January – February .
- Gerald H. Clarfield and William M. Wiecek (1984). Nuclear America: Military and Civilian Nuclear Power in the United States 1940-1980, Harper & Row, New York, p. 208.
- Radioactive I-131 from Fallout - National Cancer Institute
- Overview of Hanford and Radiation Health Effects - Hanford Health Information Network - WA State Dept. of Health
- Hanford Downwinders Litigation Website. Downwinders.com. Retrieved on 2009-09-27.
- McClure, Robert (May 21, 2005). "Downwinders' court win seen as 'great victory'". Seattle Post-Intelligencer. Retrieved 2009-09-27.
- "Nuclear Weapons Test Map", Public Broadcasting Service
- Arjun Makhijani , Brice Smith and Michael C . Thorne, "Healthy from the Start: Building a Better Basis for Environmental Health Standards— Starting with Radiation," Science for Democratic Action, vol. 44.4, February 2007: http://www.ieer.org/sdafiles/14-4.pdf
- Isabel Woodman, “Breast feeding reduces risk of breast cancer, says study,” British Medical Journal, v.); Jul 27, 2002
- Norman Brier, PhD, “Understanding and Managing The Emotional Reactions To A Miscarriage,” Obstetrics & Gynecology . 1999;93: 151-155
- Assessment of the Scientific Information for the Radiation Exposure Screening and Education Program (2005), 2 http://books.nap.edu/openbook.php?record_id=11279&page=1
- Schinder, Keith, "A Valley of Death for the Navajo Uranium Miners," New York Times, May 3, 1993.
- Nuclear Testing and the Downwinders from the website of the Utah State Historical Society
- View documentary short "Downwinders: The People of Parowan"
- Article "A people's truth"