Project GABRIEL was an investigation to gauge the impact of

nuclear fallout 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 radioac ...

resulting from

nuclear warfare Nuclear warfare, also known as atomic warfare, is a theoretical military conflict or prepared political strategy that deploys nuclear weaponry. Nuclear weapons are weapons of mass destruction; in contrast to conventional warfare, nuclear ...

. The

United States Atomic Energy Commission The United States Atomic Energy Commission (AEC) was an agency of the United States government established after World War II by U.S. Congress to foster and control the peacetime development of atomic science and technology. President H ...

surmised that the radioactive isotope

strontium-90 Strontium-90 () is a radioactive isotope of strontium produced by nuclear fission, with a half-life of 28.8 years. It undergoes β− decay into yttrium-90, with a decay energy of 0.546 MeV. Strontium-90 has applications in medicine and i ...

(Sr-90) presented the greatest hazard to life globally, which resulted in the commissioning of

Project SUNSHINE Project SUNSHINE was a series of research studies that began in 1953 to ascertain the impact of radioactive fallout on the world's population. The project was initially kept secret, and only became known publicly in 1956. Commissioned jointly by ...

: which sought to examine the levels of Sr-90 in human tissues and bones (with a special interest in infants) gathered from around the world.

Background

During the

Cold War The Cold War is a term commonly used to refer to a period of geopolitical tension between the United States and the Soviet Union and their respective allies, the Western Bloc and the Eastern Bloc. The term '' cold war'' is used because the ...

era, there was an escalation of the atmosphere testing of nuclear weapons. After the

atomic bombings of Hiroshima and Nagasaki The United States detonated two atomic bombs over the Japanese cities of Hiroshima and Nagasaki on 6 and 9 August 1945, respectively. The two bombings killed between 129,000 and 226,000 people, most of whom were civilians, and remain the onl ...

in 1945, testing continued and the scale increased with the first hydrogen bomb in 1952. Soon after the United States tested the

hydrogen bomb A thermonuclear weapon, fusion weapon or hydrogen bomb (H bomb) is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation nuclear bombs, a more compact size, a lowe ...

, the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...

followed, in 1953. The mushroom clouds that occurred from the explosions released radioactive isotopes in mass quantities. The first comprehensive study of the problem of radioactive isotope release began in spring 1949 with a one-man project called GABRIEL, conducted by Nicholas M. Smith Jr. at

Oak Ridge National Laboratory Oak Ridge National Laboratory (ORNL) is a U.S. multiprogram science and technology national laboratory sponsored by the U.S. Department of Energy (DOE) and administered, managed, and operated by UT–Battelle as a federally funded research and ...

. Smith produced his first report in 1949. Project GABRIEL was revived in mid-1951 because bombs that were dropped had brought up concerns people had about the dangers of strontium-90.

(AEC) was interested by GABRIEL's report though they said it was lacking in hard data and needed independent confirmation of the tests. After reviewing Project GABRIEL in 1953, it was given first priority status. The secret project would define "practical limits" for using atomic weapons. A task team was assembled and the codename used was "Project HORN." In 1954, AEC argued that fallout was harmless because there was not enough evidence to prove that fallout would harm humans, animals, or crops. The AEC campaign persuaded the public that the worldwide fallout was harmless. This claim was later disputed when scientists announced publicly that there was no safe level of radiation. This was confirmed in a confidential report by a geneticist for the AEC. By 1954 and the

Castle Bravo Castle Bravo was the first in a series of high-yield thermonuclear weapon design tests conducted by the United States at Bikini Atoll, Marshall Islands, as part of ''Operation Castle''. Detonated on March 1, 1954, the device was the most powerful ...

incident, it was obvious that radioactive fallout was dangerous to humans. The

Division of Biology and Medicine dealt with efforts directed towards experimental and field studies and the correlation of data dealing with Project GABRIEL. The

RAND Corporation The RAND Corporation (from the phrase "research and development") is an American nonprofit global policy think tank created in 1948 by Douglas Aircraft Company to offer research and analysis to the United States Armed Forces. It is financed ...

, Laboratories at

Columbia University Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhatt ...

, AEC's New York office, the

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...

, an exclusive group of scientists,

UCLA The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California. UCLA's academic roots were established in 1881 as a teachers college then known as the southern branch of the California St ...

, and the

United States Air Force The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...

were all involved in collection and testing of samples from around the world for radioactive fallout.

Testing strontium-90

After the hazards of strontium-90 became evident, the next step was to focus on impact and damage per detonation. Smith's tests focused primarily on how many atomic weapons could potentially be detonated before

radioactive contamination Radioactive contamination, also called radiological pollution, is the deposition of, or presence of radioactive substances on surfaces or within solids, liquids, or gases (including the human body), where their presence is unintended or undesirab ...

of air, water and soil became a long-term effect on crops, animals and humans worldwide. In 1949, Smith estimated that it would take 3,000 Hiroshima-sized detonations in a single growing season to see if it have an effect on people who ate crops in affected areas. In 1951, Smith repeated this study with new information from the previous two detonations. With the new information, he then calculated that 10,000 Hiroshima-sized detonations would be needed before the long-term hazards became serious. The testing was done with bones, urine and tissue samples collected worldwide. These samples were all tested for nuclear fallout, yet were falsely studied under the guise of nutritional importance and naturally occurring radon. It was determined that Sr-90 is a "bone-seeker," depositing in bones and marrow after ingestion. Civilian prisoners were considered for certain radiation testing, mainly Utah State prison inmates. One document revealed tests done on the bones of a stillborn baby showed that strontium-90 levels were 36% higher than the average 55% of other stillborn.

Studies related to Project GABRIEL

Project GABRIEL opened a wide range of questions about formation, transformation, fallout and biological hazards due to bomb debris. GABRIEL supported work in research projects that might apply to the side effects of nuclear war. It was the sole support of the major research effort of

, which tested biological damage from radioactive fallout of Sr-90. By 1954 Project GABRIEL included about 70 investigations supported by the Division of Biology and Medicine. At a summer conference that was hosted by the

the estimate of detonations was revised and increased to 25,000 megatons worth of damage. Project Sunshine was led by radiation physicist

Willard Libby Willard Frank Libby (December 17, 1908 – September 8, 1980) was an American physical chemist noted for his role in the 1949 development of radiocarbon dating, a process which revolutionized archaeology and palaeontology. For his contributions ...

on July 21, 1953. Libby realized GABRIEL lacked data in other aspects of fallout, examined

carbon-14 Carbon-14, C-14, or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. Its presence in organic materials is the basis of the radiocarbon dating method pioneered by Willard Libby and coll ...

and developed

radiocarbon dating Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon. The method was dev ...

. The Project GABRIEL report by the AEC was issued in 1954, while the RAND Corporation issued their report on Project SUNSHINE in 1953. Both Project GABRIEL and SUNSHINE played a direct role in the reorganization of the AEC's Division of Biology and Medicine in 1957.

References

{{reflist Radiation health effects research United States Atomic Energy Commission Nuclear fallout 1949 establishments in the United States 1954 disestablishments in the United States 1940s in military history 1950s in military history