Fukushima cancer risk not as serious as thought, UN says

Japan's nuclear disaster at Fukushima in 2011 has had less of an impact on wildlife and human health than expected, according to a recently finalized UN report.

The Scientific Committee on the Effects of Atomic Radiation cast a broad net, looking at potential health effects in people living in the area, which was hit by an earthquake and tsunami three years ago.

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The UN researchers looked for iodine-131 (a form of radioactive iodine) and cesium-137 in fish caught off the northeast coast of Japan and found nearly all types actually had lower than the acceptable levels of those radionuclides, which had escaped into the air and water from the Fukushima nuclear plant.

The UN body also looked at the measured incidences of thyroid cancer. Iodine-131 can increase the risk of this type of cancer, and early reports conducted after the disaster said there was an increase of precancerous thyroid lesions in people living in affected areas.

However, the UN report said the increase in the number of nodules found was due to increased screening, and that there was no difference between the population in 2006 and the population that was exposed to the radiation.

"The doses to the general public, both those incurred during the first year and estimated for their lifetimes, are generally low or very low," the report said.

"No discernible increased incidence of radiation-related health effects are expected among exposed members of the public or their descendants," it said.

CBC science contributor Dr. Torah Kachur compares the levels of radiation in fish near Fukushima and in everyday foods, such as potato chips. Click here to listen to the interview on CBC Radio's Homestretch.