> That's basically a judge saying it. The scientific basis is very unclear.

"In January 2015, the MHLW [Ministry of Health, Labour, and Welfare] compiled medical knowledge on lung cancer and radiation exposure in a report resulting from a review meeting of medical experts, and published the immediate view similar to that for thyroid cancer. The first claim for case of lung cancer was approved by MHLW in August 2018, and this was also the first case involving death."

--From "Responses and Actions Taken by the Ministry of Health, Labour and Welfare of Japan on Radiation Protection at Works Relating to the Accident at TEPCO’s Fukushima Daiichi Nuclear Power Plant 9th Edition (Fiscal Year of 2021)" https://www.mhlw.go.jp/english/topics/2011eq/workers/ri/ar/r...

I understand that he received an estimated 74 mSv of radiation, somewhat below the level of 100 mSv acute / 300 mSv annual that has been shown to cause a measurable increase risk of cancer (e.g. from 40% lifetime risk to 40.1% lifetime risk). It's extremely dubious to say that this was definitely from Fukushima radiation. If that dose is accurate, the likelihood of it being from Fukushima radiation is probably less than 1%. Not impossible. But not likely, and far from a sure thing.

For comparison, the 23 firefighters who died from acute radiation syndrome at Chernobyl got doses as high as 13,400 mSv, almost 2000x higher than this guy.

It seems dubious to apply this kind of population statistics to individuals at all.

> I understand that he received an estimated 74 mSv of radiation

"The ministry said he had been exposed to about 195 millisieverts (mSv) of radiation. The International Commission on Radiological Protection recommends avoiding more than 1-20 mSv per year, and according to Reuters, exposure to 100 mSv a year is 'the lowest level at which any increase in cancer risk is clearly evident.'" https://time.com/5388178/japan-first-fukushima-radiation-dea...

That's 100 mSv acute. Did he get it acutely (i.e. in a day or two) or over years? If acute then yes, the measurable increment over a background 40% lifetime risk could be due to Fukushima. So then the question is what's the increment? Let's estimate that it's 1% (based on the noisy data at these still quite low doses). In that case, there is a 1 in 40 chance that his cancer death in 2016 was due to Fukushima in 2011.

It it wasn't acute and accumulated over >1 year, then there's a ~0% chance it was from Fukushima radiation.