Thyroid cancer in Fukushima children increased 20-fold via Alex Rosen, IPPNW
Latest results of the Fukushima thyroid screenings confirm worrying trend
In 2011, people in Japan were exposed to radioactive fallout. Some still live in contaminated regions where they are exposed to elevated levels of radiation on a daily basis: radioactive hot-spots on the side of the road, in rice paddies or in sandboxes, contaminated mushrooms or algae, contaminated groundwater, and recontamination from forest fires or flooding.
One of the most dreaded effects of radioactive exposure is the development of cancer through mutation of the DNA. Thyroid cancer in children is certainly not the most dangerous form of radiation-induced cancer, but it is probably the easiest to detect. For one thing, the latency periods before a cancer develops are relatively short, while at the same time, thyroid cancer in children is an extremely rare disease, so that even a slight absolute increase can be statistically detected. Accordingly, in 2011, there was great pressure on Japanese authorities to investigate the development of thyroid cancer in children and adolescents in Fukushima by conducting long-term screening examinations.
For almost 10 years now, Fukushima Medical University has been regularly examining the thyroid glands of people who lived in Fukushima Prefecture at the time of the meltdowns and were under 18 years of age. Initially, this group consisted of about 368,000 individuals. Of these, 300,000 (about 82%) were successfully screened in the first few years. After the initial screening (2011-2014), follow-up examinations of these children took place every two years. The second examination has already been completed, the third examination is in its final stage, the fourth series of examinations has been running since 2018, and the fifth since 2020.
In the initial investigation in Fukushima, 116 abnormal biopsies were found. Amongst these, 101 cases of cancers were found that were so aggressive that they required surgery. The patients with abnormal biopsies were 6 to 18 years old (average of 14.9 years) at the time of the nuclear disaster. This unexpectedly high number was explained by Fukushima Medical University as a screening effect, the phenomenon of identifying more cases of disease in large-scale screening than would be expected. While the exact magnitude of this screening effect in the first round is unknown, it can be ruled out that the increased cancer rates in subsequent screenings are consequences of a screening effect, because all of these children had already been examined and found to be cancer-free in previous screenings. They must therefore have developed the cancer between the screening examinations.
The declining number of expected thyroid cancer cases between 2016-2021 is attributable to declining screening participation rates. Since these people’s cancers would no longer show up in screenings, the number of expected cancer cases also declines. While, out of a total pediatric population of little more than 380.000, about 300,000 children were examined in the initial screening from 2011-2014, that number dropped by 10% to about 270,000 in the second screening from 2014-2016 and by another 10% in the third screening from 2016-2018 to just under 218,000. To date, only about 181,000 children have been screened in the fourth screening, and only 41 have been screened so far in the fifth screening. In relative terms, the percentage of children screened in Fukushima has dropped from an initial 82% in the 1st screening to 71% in the 2nd screening, 65% in the 3rd screening, and currently to 62% in the ongoing 4th screening.
There seems to be a system behind this trend: Fukushima Medical University, which is in charge of the study, has been sending staff to schools in the prefecture for years to educate children about their “right not to participate” and the “right not to know”. On the study forms, there is now a prominent “opt-out” option for people who wish to be removed from the screening. FMU seems to encourage people to opt out of the study. The drop in participation can also be explained by the removal of people over 25 years from the main study. Are FMU staff concerned that the disturbing trend of increasing numbers of thyroid cancer cases will continue? Are they uncomfortable with data that contradicts the thesis, propagated since the beginning of the nuclear disaster, that the multiple meltdowns would not lead to additional cancers?
In addition to thyroid cancer, other types of malignancies and other diseases triggered or adversely affected by ionized radiation are expected to increase. The FMU thyroid studies represent the only scientific study that can provide any relevant information at all about the health consequences of the Fukushima nuclear disaster. And they are currently in danger of being undermined by the proponents of nuclear energy such as IAEA, which has entered a cooperation with FMU and by the Japanese government, which is trying to dispel any concerns about the meltdowns and nuclear energy as a whole.
The people of Japan have an inalienable right to health and to life in a healthy environment. The examination of children’s thyroid glands benefits not only the patients themselves, whose cancers can be detected and treated at an early stage, but also the entire population, which is affected by irradiation from radioactive fallout. The correct continuation and scientific monitoring of thyroid examinations are therefore in the public interest and must not be thwarted by political or economic motives. It is important to continue to critically accompany these developments from the outside.
Dr. med. Alex Rosen
Pediatrician and Co-Chair of the German affiliate of IPPNW
Note: this article was first published in IPPNW Germany’s member magazine ippnw forum in 03/21
- Publications of the results of the 40th meeting of the Fukushima Prefectural Health Investigation Review Committee held on January 15, 2021 (in Japanese). https://www.pref.fukushima.lg.jp/site/portal/kenkocyosa-kentoiinkai-40.html
- Publication of Fukushima Prefectural Radiological Health Management Center on Geographical Distribution of Thyroid Cancer Incidence in Fukushima, Nov. 30, 2017 https://www.pref.fukushima.lg.jp/uploaded/attachment/244313.pdf
- Yokoya S et al. “Investigation of thyroid cancer cases that were not detected in the Thyroid Ultrasound Examination program of the Fukushima Health Management Survey but diagnosed at Fukushima Medical University Hospital.” Fukushima Journal of Medical Science, 2019:65:122-127 www.jstage.jst.go.jp/article/fms/65/3/65_2019-26/_html/-char/ja
- National Cancer Incidence Based on Japan Cancer Registries (1975-2013), retrieved 2019-08-13. http://ganjoho.jp/en/professional/statistics/table_download.html