Original URL: http://www.theregister.co.uk/2014/02/26/fukushima_radioactivity_a_complete_nonissue_on_west_coast_also_for_fukushima_locals_in_fact/

Fukushima radioactivity a complete non-issue on West Coast: Also for Fukushima locals, in fact

Boneheads get their knickers in a twist anyway

By Lewis Page

Posted in Science, 26th February 2014 15:26 GMT

A new study carried out in the "radiation zone" areas just outside the Fukushima nuclear powerplant in Japan has confirmed that the lifetime health risk to people living there from the damaged powerplant is so small as to be undetectable. Naturally, Californians almost 5,000 miles away are still terrified for their own safety.

NOAA map of post-Fukushima ocean wave heights

OMG! That looks bloody scary

As the San Francisco Chronicle notes, "some Internet sites continue claiming that dangerously radioactive ocean water from Fukushima is showing up along California beaches," and that's all anyone needs to get into a flap in the Golden State. It probably doesn't help that the BBC speaks of an "incoming radioactive Fukushima plume" which is about to "hit the west coast of North America".

But the radioactivity which is to "hit" California will be utterly, completely minuscule. The water in the "plume" which scientists are "tracking" is so radiologically inert that in an entire tonne of it, just one lonely atom of caesium from Fukushima is decaying each second. For context, healthy human body tissues are around 50,000 times more radioactive than that.

"I know that the people in Japan are facing the worst of the conditions but I also worry about my children here in California," California resident and member of citizen action group "Fukushima Response" Maggy Hohle tells al Jazeera. "Will there be high levels of radiation in the air and will my children be able to swim in the Pacific Ocean in the coming years?"

Provided that you consider it safe for them to hug your enormously more radioactive body, Ms Hohle, you should also consider it safe for them to swim in the Pacific, yes.

But hey - forget airheads in California. What about those poor people in Japan? Alright, most of them are probably OK too, really. But what about people who actually live in Fukushima province? What about people who live "In the Radiation Zone", as Discovery News puts it, in places like Minamisoma City. Consider this searing reporting on "the children of Minamisoma City":

The city of Minamisoma was not only devastated by the March 11 earthquake and tsunami, but it is now battling a silent threat that is potentially fatal: exposure to the radiation that continues to be released following the explosion at the Fukushima nuclear power plant.

And amidst the chaos and confusion, we learned something unbelievable: the children who remained in the zone just 20-30 kilometers from the damaged nuclear power plant were heading back to school.

Actually you'll suffer a heavier radiation dose living in the USA than you would near Fukushima

Well, a large group of Japanese scientists have just carried out a full study into radiation dose rates in several areas "in the Radiation Zone", including Minamisoma - the dangerous Haramachi area of it, nearest to the plant - as it happens. Their conclusions?

For Haramachi residents specifically, as at 2012 the extra radiation dose due to the Fukushima incident amounted to 1.51 milliSieverts per year. In 2022 this will have dropped to 0.53 mSv/yr, as deposited caesium isotopes decay away. By 2062 the figure will be 0.2 mSv/yr.

Normal background radiation dose in Japan is about 2 mSv/yr, so a Haramachi resident is now sustaining about 3.5 mSv/yr, which will drop to 2.5 in 8 years' time and 2.2 in 2062.

For context, the average background radiation dose sustained by a resident of the USA in normal times is around 3.1 mSv/yr. On average, US citizens generally manage to double this dose voluntarily, mainly by having various sorts of medical scans. Ironically, Ms Hohle faces a noticeably greater lifetime radiation dose than she would if she lived in Haramachi. If she's worried about tiny radiation doses, she ought to take her children and move to Fukushima province.

The end result of the study, as has been expected by scientists for a long time, is that the possible increased cancer risk to local Fukushima residents over their lifetime will be so small as to be epidemiologically undetectable. It won't ever be possible to say that any cancer cases were caused by Fukushima. As nobody - no plant workers, nobody - has suffered enough radiation dose to actually get radiation sickness either, that means the total radiation deaths and injuries count from Fukushima will be zero.

The new study, published in the august Proceedings of the US National Academy of Sciences, can be read for free online here (pdf).

Analysis

It's worth noting here that the Daiichi reactors and cooling pools were not particularly safe as nuclear powerplants go: they were a very old, long outmoded design. They were hit by earthquakes and tsunamis wildly beyond what they were rated to withstand, in the second worst nuclear power disaster that has ever happened anywhere.

And as a result ... absolutely nobody's health has been or will be measurably harmed. That's a pretty impressive safety performance.

We stand by our original headline: Fukushima was a triumph for nuclear power, not a disaster. If there's one lesson to learn from it, it's that nuclear power is very safe indeed. ®