The Environment Ministry has begun thyroid gland tests on children in faraway Nagasaki Prefecture as part of efforts to gauge the effects of radiation fallout from last year's nuclear disaster.
The Environment Ministry has begun thyroid gland tests on children in faraway Nagasaki Prefecture as part of efforts to gauge the effects of radiation fallout from last year's nuclear disaster.
Those children will serve as a control group for kids undergoing similar tests in Fukushima Prefecture, where the disaster occurred.
By comparing the results from the two prefectures, officials expect to gain a better grasp of the issue.
The Fukushima prefectural government has implemented what it intends to be a lifelong thyroid gland test program for 360,000 children who were aged 18 or under when the disaster began to unfurl in March 2011.
The program draws on the finding that cases of thyroid cancer soared among children after the Chernobyl nuclear disaster in 1986.
That survey found that 40 percent of 96,000 or so children for whom test results are available developed thyroid gland problems, such as nodules, or lumps, and cysts.
One child was diagnosed with thyroid cancer.
Despite parental concerns about radiation exposure, it remains difficult to say with any certainty whether the 40-percent occurrence rate is alarmingly high or not. This is because no exhaustive thyroid gland tests have been done on children using highly reliable ultrasound technology.
The Environment Ministry commissioned the Japan Association of Breast and Thyroid Sonology to conduct thyroid gland checkups on 4,500 children aged 18 or under in three prefectures outside Fukushima.
In Nagasaki Prefecture, thyroid gland tests that use the same ultrasound and diagnostic standards as in Fukushima Prefecture have started on about 1,100 children attending Nagasaki University's kindergarten, elementary school and junior high school. Similar tests will begin shortly at a senior high school in the prefecture.
Nagasaki Prefecture was chosen as a study area partly because of its remoteness from Fukushima as well as the absence of obvious health issues stemming from the nuclear disaster and the presence of experts in thyroid gland testing.
The Japan Association of Breast and Thyroid Sonology also plans to carry out similar tests in Yamanashi and Aomori prefectures.
The results of the tests in the three prefectures will be available by the end of fiscal 2012. Parents and custodians will be notified of the test results on an individual basis.