TOKYO, Oct. 10 (UPI) -- Japan began testing about 360,000 children in Fukushima for any thyroid gland damage caused by radiation from the nuclear crisis in the prefecture.
The children are receiving the ultrasonic thyroid examinations because of a radiation leak at the Fukushima Daiichi nuclear power plant, where reactors were crippled by a March 11 earthquake and tsunami.
The testing started Sunday.
The thyroid gland in children is particularly vulnerable to radiation damage.
Authorities said the scale of the testing is unprecedented in the world, Kyodo News reported.
The report said the prefectural government decided to implement the wide-scale program because of parents' concerns about evidence of increased thyroid cancer among children after the 1986 Chernobyl disaster in Ukraine.
Among the first to face the tests at the Fukushima Medical University are children from the two towns nearest to the quake-hit nuclear plant, the Voice of America reported.
The March 11 disaster also killed or left missing about 20,000 people and caused damage to the Japanese economy running into the hundreds of billions of dollars.
Dr. Shinichi Suzuki at the medical university said it will take several years to carry out preliminary examinations of young people -- 18 and under -- because it can take a long time for any irregularities in the thyroid to manifest as cancer, the VOA reported.
There will be follow-up tests every two years until the children reach the age of 20 and similar tests will be done every five years after that.
The leak of radiation from the plant has yet to be fully halted, and thousands of people who lived within a 12.5-mile radius of the plant have not been allowed to return home.