It's interesting to see the headlines in various news sources over the release of this report. Japanese authorities are upset and say the risk has been overhyped and overblown. Other articles say the risk has been minimized and downplayed.
Personally, I'm a skeptic until real data comes out, although that will be after the fact by that time. I lived in Manhattan during 9/11 and I remember how the City of New York, the EPA, and various other agencies swore up and down on their mothers' graves that the air on the pile at Ground Zero was safe. Look how well that turned out for first responders who worked that scene.
These cancer risk models are only as good as the data that goes into them, and data on radiation levels are not very good. Heck, the EPA turned
off their radiation monitors shortly after the disaster. Hmmm, now why would they do that?
There is ongoing monitoring of radiation in the Fukushima area, but when you read about these monitoring stations, it's laughable. Typically, an area is decontaminated, the topsoil is dug up and trucked away, a brand new concrete platform is poured, and then the monitoring station is placed on top of the slab. Concerned citizens record far higher radiation levels just a few meters away in the soil than what the official station measures.
Regardless of what the actual risk is, the people in the region suffer tremendous psychological stress to this day, and they and their children will be stigmatized for the rest of their lives, the same way that their grandparents and greatgrandparents who lived anywhere near Hiroshima and Nagasaki were stigmatized after we dropped atomic bombs on them. The Japanese are extremely cohesive, but conversely, if you're seen as "different", the negative impact can be even more extreme.
I lived in Japan and IMHO I'd say the stigmatization ranks up there with being permanently identified as a sex offender in the US in terms of discrimination in making friends or finding a spouse, in housing, in employment, in being alienated from your own relatives, etc. I know suicides have been up in the Fukushima region, and that will likely continue for years or even decades.
A recent article on the topic. Very bleak.
After Fukushima: families on the edge of meltdown Edit: I should clarify my point from above. If these residents try to move away from the contaminated areas, they will be stigmatized by the new people around them. Additionally, if they stay put, there is great peer pressure not to "make waves" or do things that upset other people, so there is constant subtle and not-so-subtle pressure to act like nothing is wrong. Most of us have heard that famous Japanese saying, "The nail that sticks up gets hammered back down." It's a damned-if-you-do and damned-if-you-don't dilema for these residents.