A Fukushima Worker Has Been Diagnosed With Cancer Linked to the Disaster

Japan's health ministry said on Tuesday that a construction worker's leukemia was likely caused by radiation from the Fukushima nuclear power plant, which suffered a catastrophic failure of its cooling systems after being hit by a powerful tsunami in 2011. It is the first time Japan has acknowledged a radiation-related diagnosis from the disaster.

The 41-year-old construction worker, who was not named in news reports, installed protective covers at Tokyo Electric Power Company's Fukushima Daiichi plant from 2012 to 2013. He absorbed 15.7 millisieverts (mSv) of radiation during that time, according to a healthy ministry official cited by Reuters. A total of 19.8 mSv was recorded in his body.

The worker's exposure amount was lower than the 50 mSv allowable for nuclear industry workers, but the government decided that radiation could not be ruled out as a factor, the official said.

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In the United States, a person might receive an average dose of 4 mSv per year from natural and medical sources, said David Brenner, director of the Center for Radiological Research at Columbia University in New York City.

"It is possible, but statistically unlikely, that a dose of 15 mSv was the cause of leukemia," Brenner said.

He said that it is generally very hard to assess the effects of radiation, especially in relation to cancer.

"At Fukushima, it is probably rather too early to be looking for increased cancer risks on a large scale, with the exception of a couple of cancers that we know from Chernobyl are increased within the first decade, namely leukemia and thyroid cancer," Brenner said. "With leukemia and thyroid cancer, we have seen that effects tend to emerge after four years."

Edwin Lyman, a senior scientist at the Union of Concerned Scientists and co-author of Fukushima: The Story of a Nuclear Disaster, said the health impacts of radiation might not be seen for a long time.

"But the fact that the Japanese government is acknowledging that even a low dose of radiation can be linked to cancer is significant," he said. "It's a step forward, considering that the Japanese government has maintained for a long time that low doses are not harmful."

According to NHK, Japan's largest broadcaster, the ministry will award compensation to the worker, who was diagnosed with leukemia in 2014. Nuclear plant workers can apply for compensation if they have been exposed to radiation of 5 mSv in a year and developed cancer after one year.

More than 40,000 workers participated in the clean up efforts following the disaster, the world's worst nuclear accident since Chernobyl.

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Experts remain divided over the effects of radiation following the disaster. In encouraging recovery efforts, the Japanese government and the nuclear industry have said that the effects of radiation on health have been minimal.

But an October AP report found that children living near the Fukushima plant had rates of thyroid cancer that were 20 to 50 times higher than elsewhere.

As of July this year, the Japanese government has doled more than 7 trillion yen, or $59 billion, in compensation payments.

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