Destruction after an earthquake and tsunami struck in March 2011, off the coast of north-eastern Japan. Photo / Getty Images
She was in intermediate school in March 2011, when three reactors melted down at the Fukushima Daiichi nuclear power plant about 65km from her home in northern Japan.
Living outside the evacuation zone, she continued to go about her life, shopping and cycling to school.
Four years later, a screening found a malignant tumour in her thyroid, a gland in the neck that is known to be vulnerable to radioactive particles released during a nuclear accident.
When she got the diagnosis, a doctor told her immediately that the growth was unrelated to the disaster.
She wondered how the doctor could judge that without making further checks. The young woman, now in her 20s, asked that her name not be used because she has faced intense social pressure not to speak out.
Her question is one that has not been conclusively resolved 14 years after a huge earthquake and tsunami knocked out cooling systems at the plant, leading to explosions at its reactor building that showered this region of northern Japan with radioactive particles.
A few weeks ago, the Fukushima prefecture screening committee restated its conclusion that the triple meltdown has not caused long-term health effects.
Many medical experts, including those at international agencies, have made similar findings.
There is scepticism from many residents and a minority of medical experts, who say authorities haven’t done enough to prove their case.
The young woman from Fukushima has joined six other people with cancer in a lawsuit to seek compensation from the plant’s operator, Tokyo Electric Power Co.
The company says there’s no scientifically proven link between the cancers and radioactive particles released by the disaster. The next hearing will be held on September 17, though a ruling is probably years away.
Much of the dispute has focused on the thyroid screening programme, which has been the only large-scale, systematic effort to detect a major health effect from the disaster.
The study found cancer rates that were many times higher than had been expected, but the meaning of that result has been fiercely contested.
Medical experts on both sides agree that the question of whether or not the cancers are linked to the nuclear accident could be resolved by conducting a similarly large-scale screening elsewhere to serve as a comparison, but authorities have refused to do that.
“Without a base-line study, there is no way to conclude for sure whether or not these cancers are related to radiation,” said Kazuo Shimizu, a thyroid surgeon who served on a committee supervising the screening but resigned in 2017.
Lessons from Chernobyl
Started seven months after the meltdown, the Fukushima programme is still under way.
It has conducted several rounds of checks to monitor the thyroids of people who were children at the time of the accident.
The focus was a lesson of the 1986 nuclear accident at the Soviet power plant in Chernobyl, which led to a proliferation of thyroid cancers in present-day Ukraine and Belarus.
When the results of the first round of screening were announced starting in 2015, they showed an unexpectedly large number of the cancers, which were thought to be rare in children.
The number has continued to climb as five more rounds of screenings have been conducted.
According to the most recent figures released last month, the screenings have found 357 cases of thyroid cancer in some 300,000 people, though one was later ruled to be benign.
With an additional 47 cases that have been diagnosed separately, a total of 403 people have been found to have developed thyroid cancers. This is some 25 times more than the doctors expected based on other studies elsewhere.
While the medical experts running the programme agree these numbers were surprisingly high, they say the large number doesn’t reflect an outbreak of cancers, but rather the discovery with modern ultrasound equipment of cancers that would have been there anyway.
“What we discovered is that thyroid cancers are more common than we thought,” said Gen Suzuki, a former professor of radiation pathology who heads the committee of experts evaluating the screening results.
Suzuki said most of the cancers detected were a type that needed no treatment because they wouldn’t endanger health. As a result, they had simply gone undetected before.
Distrust of government
That conclusion of “over screening” has been endorsed by Japan’s national government and global health groups. These include the United Nations Scientific Committee on the Effects of Atomic Radiation, which in 2020 said that “the apparent detected excess of thyroid cancers is probably unrelated to radiation exposure”.
However, there is scepticism in Japan, where there has been deep-seated public mistrust in the official handling of the Fukushima disaster that goes back to the first days, when authorities hid the size of radiation releases.
Prefectural officials have been criticised for stating at the outset that their screening programme’s goal was “to put the public mind at ease” about radiation health risks, suggesting its conclusions were foregone.
Critics in the medical community say a closer scrutiny of the screening’s results show a possible link between the cancers and levels of radiation, as people who were children in towns around the Fukushima Daiichi plant have developed cancer at rates that are three times higher than those who lived furthest away.
Suzuki says this is just a random variation in the statistics.
The dispute points to a problem: It is impossible to determine the exact cause of an individual case of cancer.
The best most researchers can do is say that radiation increases the chances of getting a tumour.
Medical experts say that by looking at thyroid cancer rates in another part of Japan, or among Fukushima residents who were not children at the time of the accident, it would be possible to determine whether the number detected by the current screening was high or not.
Medical authorities in three other prefectures made one effort to conduct such a survey, but it was halted after the testing of about 4400 people found one with cancer.
The Ministry of the Environment said that was enough to show a roughly similar rate as the Fukushima cancers, but medical experts called the number of people tested too small to serve as a statistically valid comparison.
“The Fukushima screening was almost 100 times larger,” Shimizu said.
Before he resigned from the committee, Shimizu faulted its conclusion that there was no link between the cancers and the nuclear disaster as premature. In an interview, he said the lack of a comparative study was a main reason for his view.
Social pressure
Suzuki, whose term as head of the committee ended in July, agreed that a comparative study would give a definitive answer.
However, he said many doctors nonetheless oppose a new large-scale screening because it would detect tumours and growths that have no health effects, leading to unnecessary surgeries to remove them.
Some health experts say a comparative study has been blocked for political reasons.
Toshihide Tsuda, a leading critic of the Fukushima screening committee’s conclusions, says the nuclear industry has pressured the Government into denying funding for such a survey.
“They don’t want to know the real answer,” said Tsuda, a professor of environmental epidemiology at Okayama University.
Others point to the Chernobyl incident. UN nuclear and health agencies said for years that there was no link between the accident in the former Soviet Union and the thyroid cancers later found in children living around it.
It was only a decade later, after comparative studies showed the cancers appearing in post-Soviet republics to be unusual, that the agencies altered their stance.
Those diagnosed with cancer in the Fukushima study say local residents oppose any additional surveys because they would draw attention to the issue of radiation, which can hurt tourism and farming.
The young woman in Fukushima underwent surgery to remove the cancerous thyroid gland, but she developed health problems that included chronic colds and swelling in her legs. A bout of pneumonia drove her to quit her job at a Tokyo ad agency.
But her biggest source of suffering has been her inability to publicly tell her story for fear that she and her family will be attacked on social media.
The children of Fukushima still feel blocked from saying that they suffer from cancer, she said.
This article originally appeared in The New York Times.
Written by: Martin Fackler
Photographs by: Getty Images, Emile Ducke
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