UN releases report on Chernobyl survivors with thyroid cancer

The biggest negative health impact caused by the Chernobyl nuclear reactor disaster is the subsequent increase in Ukrainian thyroid cancer rates, according to a new United Nations (UN) report.

The paper, released by the UN's Scientific Committee on the Effects of Atomic Radiation, specified that more than 6,000 Russian, Ukrainian and Belarusian citizens have been diagnosed with thyroid cancer as of 2005.

Health and atomic safety officials officially consider the disaster, which occurred in 1986 in what is now the Ukraine, the worst nuclear accident in human history. It is still the only radiological event to be rated a seven - the highest level - on the Nuclear and Radiological Event Scale of the International Atomic Energy Agency (IAEA).

The UN notes that while the incidence of thyroid cancer increased dramatically among those who lived in the region of the disaster, other conditions related to radiation exposure - like leukemia - have not become more common.

They explained this disparity by pointing to nuclear fallout, specifically to iodine-131, cesium-134 and cesium-137 atoms. These radioactive isotopes, which were released by the nuclear reactor following its explosion, can be taken up by the body and then absorbed in the thyroid gland.

Beyond the effects of radiation exposure in the immediate vicinity of the reactor, the release of these ions appears to be the biggest public health threat caused by the disaster, the UN said.

The reason is that these isotopes were aerosolized, spraying into the air and spreading across much of Russia and Europe. The IAEA states that the disaster released 400 times more radioactive material into Earth's atmosphere than the atomic bomb detonated over Hiroshima.

The UN noted that this fallout is to blame for the increase in thyroid cancer among Chernobyl survivors. It added that diagnoses of thyroid carcinoma are especially among people who were children and teens in 1986, suggesting that they probably ingested more iodine-131 than other groups because of contaminated milk.