Uranium is a naturally occurring radioactive chemical element. It was formed in super novae explosions about 6.6 billion years ago. In its pure form it is a silvery colored heavy metal. It is 70% denser than lead but not quite as dense as gold and will burn in a powdered form. A little softer than steel, it is malleable, ductile, paramagnetic, weakly electropositive and a poor conductor of electricity. It will oxidize in air and can be dissolved by acids.
A piece of yellow glass made around 79 AD colored with uranium from found near Naples, Italy is the first known use of uranium. The uranium mineral called pitchblende or uraninite was noticed and reported as long ago as 1565 in mines in Saxony in northwest Germany. Uranium was first recovered in 1789 from analysis of mineral samples from the Joachimsal silver mine in the Czech Republic by a German chemist named Martin Heinrich Klaproth.
The main location for testing nuclear bombs in the United States between 1951 and 1962 was the Nevada Test Site. Eighty six nuclear bombs were exploded either at ground level or above and fourteen nuclear devices were exploded underground. Radioactive materials were injected into the atmosphere from all the tests. The government told people to sit outside and watch the mushroom clouds caused by the explosions.
The following radioactive materials were released into the air by the Hanford facility between 1944 and 1972.
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Material: |
Half-Life: |
|
Iodine-131 |
8 days |
|
Iodine-129 |
16 million years |
The United States government began construction at Hanford in south central Washington State in 1943. Three nuclear reactors and two chemical processing plants were built and operated at Hanford during the Manhattan Project to develop nuclear weapons for use in World War II. The U.S. government retained private contractors including DuPont and General Electric to oversee the production of materials for nuclear weapons.
The term “downwinders” refers to people, either individually or in communities, who have been exposed to radioactive materials as a result of nuclear fuel mining, nuclear weapons production and testing, nuclear waste disposal or nuclear accidents. The term derives from the fact that people who are downwind of an event that expels radioactive particles and gases into the atmosphere will be exposed to the fallout when the particles move through the air and fall to the ground.
Shortly after the discovery of X rays in 1895, papers began appearing in scientific publications about the negative effects of high levels of exposure to such radiation. In the first year, suggestions about how to protect against ionizing radiation were made including the three main measures that are still emphasized today, limit the exposure to the shortest possible time, maintain as great a distance from the source as possible and employ shielding of some sort.
After the Second World War, weapons research and work on civilian use of nuclear power were producing more and more radioactive materials. Scientists in the Manhattan Project had been assigned to work on what was then called “Health Physics.” A decade after the end of the war, the first conference on Health Physics was held at Ohio State University. One result of the conference was the formation of a professional Health Physics Society (HPS).
In 1988 the Radiation and Public Health Project (RPHP) was created by the United Church of Christ Commission for Racial Justice. Jay M. Gould and Benjamin A Goldman started the project as a spinoff of their work at Public Data Access, Inc. In 1995 RPHP became an independent non-profit 501(c)3 organization. The mission of the organization includes research, education and raising public awareness.
Following the Fukushima nuclear disaster in March 11, 2011, a group of friends in the United States and Japan started a dialog to discuss what they could to help the friends and family in Japan. Since monitoring for radioactivity was very important following the disaster, the availability of Geiger counters was a critical issue.
