13 Novembre 2013
November 13, 2013
Fifteen more young people in Fukushima Prefecture have received definitive or suspected diagnoses of thyroid cancer, which is often associated with radiation exposure, prefectural officials said Nov. 12.
That raises to 59 the total number of young people who have been diagnosed with or are suspected of having thyroid cancer.
All were aged 18 or under in March 2011 when the Great East Japan Earthquake and tsunami triggered reactor meltdowns at the Fukushima No. 1 nuclear plant.
The latest figures show 12 people per 100,000 who were aged 18 or younger at the time of the accident developing thyroid cancer.
That compares with an average of 1.7 people per 100,000 in the general population between the ages of 15 and 19 who contracted the cancer in 2007, according to statistics taken in four prefectures, including nearby Miyagi.
The current results are based on the latest round of testing, which covered an additional 33,000 young people in Fukushima Prefecture. To date, the prefectural government has released test results for about 226,000 people.
It is difficult to make a simple comparison, however. Thyroid cancer usually goes undetected in children unless they develop pronounced symptoms. The thyroid testing now being done in Fukushima Prefecture covers all healthy children and is designed for early detection of minor symptoms associated with the cancer.
Prefectural officials said it is unlikely there is a link between the young people’s exposure to radiation and the increased number of suspected and confirmed cancer cases to date.
Still, the prefectural government will try to ease concerns about the effects of radiation exposure on the health of children by starting new thyroid testing in the spring that will cover 25,000 children who were fetuses at the time of the nuclear disaster.
Prefectural officials maintain the age distribution of the young people who have been diagnosed with or suspected of having the cancer, unlike in the aftermath of the Chernobyl disaster in 1986, is similar to that of children with thyroid cancer elsewhere in the general population.
In the case of Chernobyl, thyroid cancer cases only began soaring four to five years after the accident. Some experts said it is unlikely that the cancer develops within three years after exposure to radiation.
Of the 15 young people and children, only eight were definitively diagnosed as having thyroid cancer. The other seven are suspected cases. Of the total number of children diagnosed as or suspected of having developed thyroid cancer, those numbers are 26 and 33, respectively. Except for one of those who was diagnosed with a benign tumor, all were aged between six and 18 as of March 2011. Their average age was 16.8.
(This article was written by Teruhiko Nose and Yuri Oiwa.)