Page 2: The United States’ Nuclear Testing Programme
On 10 May 1984, U.S. District Court Judge Bruce S. Jenkins ruled that radioactive fallout from above-ground nuclear tests in the 1950s had caused ten people to die of cancer and that the government was guilty of negligence in the way it had conducted the tests. It was the first time that the explosions at the NTS had been legally held to have caused cancers. The judge ruled that the government had also been negligent in failing to warn residents of Nevada, southern Utah and northern Arizona, who lived in the path of the tests' wind-borne fallout plumes, about the danger of radioactive contamination. The government was also said to have failed to measure distant radiation from the atomic blasts adequately and to inform the residents of ways to minimize the contamination.
Hazards of exposure to Iodine-131 [I-131]
An important study which estimated thyroid doses of I-131 received by Americans from Nevada atmospheric nuclear bomb tests was released by the National Cancer Institute (NCI) in October 1997. The study found that any person living in the United States since 1951 had been exposed to some radioactive fallout, and all of a person’s organs and tissues had received some exposure. It concluded that the most serious health consequence was internal exposure to the radioactive form of iodine, called radioiodine or I-131 (see Chart 1), which is present in fallout from nuclear weapons. Iodine-131’s half life of eight days (see Chart 1) is long enough for considerable amounts of the radionuclide to be deposited onto pasture and to be transferred to people through the consumption of dairy products. When ingested or inhaled by breast-feeding mothers, I-131 can also be transferred to nursing infants via the mother's breast milk.
Iodine-131’s half life of eight days (see Chart 1) is long enough for considerable amounts of the radionuclide to be deposited onto pasture and to be transferred to people through the consumption of dairy products.
When assessing milk contamination, the NCI found that fallout from the tests could eventually cause between 11,000 and 212,000 thyroid cancers. Those who had been children during the testing period were particularly vulnerable, with girls being at twice the risk of boys. Children who had drunk a lot of fresh milk received the highest doses.
The website of the International Physicians for the Prevention of Nuclear War cites a preliminary study of people downwind from the Hanford Nuclear Reservation, the largest nuclear weapons production facility in the United States. The study “indicates that over 20,000 children may have been exposed to the I-131, partially through contaminated milk and food. Of 270,000 people living in the area, 13,500 may have received more than 33 rads over a 3-year period well in excess of the 5-rad per year limit. Babies may have received a 2,900-rad exposure to their thyroids.”