On April 26th, 1986, the worst nuclear accident in history took place in the small town of Chernobyl, located in the Ukraine region of the former Soviet Union. The Chernobyl nuclear plant, located approximately 80 miles north of Kiev, experienced a chain reaction explosion that blew off the reactor's lid, releasing dangerous radiation. More than 30 people were killed immediately, and in the ten days after the accident, clouds of deadly radioactive materials were released into the atmosphere, exposing the people of Chernobyl to radioactivity levels estimated to be 100 times greater than the Hiroshima bomb. Radiation also traveled downwind, exposing Eastern Europeans to high levels of radiation, and contaminating food supplies that then affected other areas of Europe as well.
The radioactive materials released during the Chernobyl contained high levels of radioactive iodine, a material that accumulates in the thyroid. People, especially children, in heavily contaminated areas, which included Belarus, the Ukraine, and other areas of Eastern Europe, were heavily exposed to these iodines (particularly iodine-131, with a half-life of 8 days) via food, primarily contaminated milk, and also via breathing the radioactive clouds.
One of the continuing health effects of the Chernobyl accident has been the dramatic increase in thyroid cancer among children in the affected area.
According to the World Health Organization, the Chernobyl nuclear disaster will cause 50,000 new cases of thyroid cancer among young people living in the areas most affected by the nuclear disaster. Specifically, the rate of thyroid cancer in adolescents aged 15 to 18 is also now three times higher than it was before the 1986 disaster took place. The incidence of thyroid cancer in children rose 10-fold in children who lived in the Ukraine region.
The most dramatic rate increase is in children who were 10 or younger when the Chernobyl accident occurred, and most specifically, those who were under 4. Researchers have found that in certain parts of Belarus, 36.4 per cent of children who were under four when the accident occurred can expect to develop thyroid cancer. This rate is higher than earlier estimated, and is far above the rates for those exposed to radiation in other parts of the world. Researchers believe this high rate may be due to iodine deficiency in that geographic region.
According to the journal Cancer (2000;68:1470-1476) among children living in Belarus, thyroid cancer is more common and more severe in children who were younger than 2 years old at the time of the 1986 accident. The researchers believe that the rapid cellular growth that occurs in children under 2 facilitated a quicker and broader development of the cancer.
In addition to thyroid cancer, there is another thyroid related problem due to Chernobyl's radiation release. According to the medical journal, Lancet, children exposed to radioactive iodine due to the Chernobyl nuclear explosion may be more likely to develop hypothyroidism. Research conducted at the University of Pisa showed that exposure to Chernobyl's radiation caused the children to have more antithyroid antibodies than other children. These antibodies may cause the children to later develop hypothyroidism.