Original URL: http://www.theregister.co.uk/2011/03/22/fukushima_tuesday_2/

Fukushima's toxic legacy: Ignorance and fear

Hysteria rages unchecked as minor incident winds down

By Lewis Page

Posted in Science, 22nd March 2011 13:49 GMT

Events at the Fukushima Daiichi nuclear powerplant in Japan continue to unfold, with workers there steadily restoring redundancy and containment measures across the site. It remains highly unlikely that the workers themselves will suffer any measurable health consequences from radiation, and – continued media scaremongering notwithstanding – effects on the public look set to be nil.

Operations at the plant itself continued yesterday, with powerful mobile pumping equipment set up at both the No 3 and No 4 reactors there to refill the spent-fuel pools at those buildings.

Water levels in those pools were thought to be at low levels last week, raising the possibility of damage to the spent rods from their own internal heating – though this is hugely less than that present in a reactor core, and experts have differed on the point of whether such damage would actually be significant. All sides agree, however, that with the three damaged cores effectively stabilised using seawater cooling the pools had become the greatest potential source of radiation at the site. Efforts to restore a deep layer of water over the spent rods have been the main focus of operations at Fukushima Daiichi since the middle of last week.

Both pools are now being continually topped up using mobile vehicles capable of squirting large amounts of water into the pools from 20m+ heights, the vehicles left running unattended to reduce the radiation doses sustained by their operators. At first a vehicle (and mobile Super Pump Trucks) supplied by Tokyo fire department's elite Hyper Rescue unit was employed, but some reports indicate that this was damaged by being left running for 13 hours at the weekend. Additional vehicles normally used to pump concrete at high-rise construction sites are now in play and cooling of the pools continues.

Personnel were briefly evacuated from the area of No 3 during the afternoon yesterday (UK time), when white smoke was seen coming from the reactor building. This could have been a sign of hydrogen being emitted, presaging a hydrogen explosion of the sort which wracked the site in the days following the quake. However the smoke – which could equally have been steam resulting from pool cooling water pouring down through the building – then declined. Radiation levels and pressure/temperature readings from the No 3 core remained steady and workers returned to No 3 as the smoke emissions ceased.

Meanwhile efforts to restore grid power from off site continued, with power provided at all reactors as of the latest reports. Nos 5 and 6 are now considered fully safe, with cores at cold shutdown status and spent-fuel pools running normally. Engineers are still restoring services including instruments and cooling at 1 and 2: it has been reported that the spent-fuel pool at No 2 is now being topped up using water from a fire engine connected to its usual cooling pipework. External power lines have been connected to switching equipment serving Nos 3 and 4 but plant operator TEPCO doesn't expect to fully restore power there until later in the week.

Radiation levels measured inside the plant continue to be such as to require workers there to carefully manage their dose rates, but not such as to mean any long-term health worries. Workers are permitted to sustain a total annual dose of 250 millisievert before being withdrawn from the operation, which is not such as to cause them or their families any concern. As only small numbers of personnel are involved, and cancer is a very common cause of death, future investigations decades from now will almost certainly not be able to attribute any cases of cancer among the workers to service during the current incident.

Not only is this not Chernobyl – even Chernobyl was not Chernobyl

Radiation near the reactors rises to 2-3 millisievert/hour during planned venting operations from the damaged cores, but workers are pulled back ahead of these. In general their exposure rates are much lower, permitting them to keep doing shifts inside the plant for months if need be – though as soon as the situation is downgraded from a lifesaving operation to one intended merely to save equipment, which could be quite soon, the annual exposure limit will probably be cut to 100 millisievert. So far only one worker is known to have surpassed this reduced level, which is the point at which – should large numbers of people be exposed – a slightly higher cancer risk later in life becomes measurable.

The main risk to the Fukushima workers is from ordinary fires and explosions, of the same sort which have been seen all across the stricken region, which have so far injured 14 people on site but killed none. The quake itself did kill one nuclear worker (at a different powerplant, Fukushima Daini) who was in a crane cab when it struck, and two others have been missing since the tsunami hit. Nobody has been hurt at any nuclear site since last Tuesday.

Outside the plant, radiation levels are being monitored at many locations by a variety of Japanese and international agencies. Thus far the highest reported level was a dose rate of 0.16 millisievert/hour picked up by an IAEA team at the edge of the 20km evacuation zone yesterday, widely reported under scaremongering headlines but nonetheless insignificant. Such a level would have to be sustained for a month continuously before any increased cancer risk occurred. Readers should also bear in mind that this increased risk would be a tiny fraction of a single percentage point; ie you have say a 25 per cent chance of dying of cancer one day anyway, varying mainly on such factors as whether you smoke. If that IAEA reading of radiation somehow stayed steady (it cannot, as most of the isotopes causing it have short half-lives) and you remained outdoors at that location continuously for at least a month, your cancer chance would then be 25.0001 per cent or similar.

There is no indication that the IAEA reading was anything more than a brief spike. Japanese monitoring teams also reported a brief rise in levels to 0.05 millisievert/hour at one location near the plant.

In summary, no radiation levels of any public-health concern have been detected beyond the plant fence.

There also exists the related issue of food contamination, which has also stoked huge levels of public fear in the last 48 hours or so since initial sampling results became available. Again, however, absolutely nothing of any concern has been revealed so far, though the Japanese government has bowed to the hysteria and instituted a precautionary, temporary ban on spinach and kakina (another leafy vegetable) from four provinces. The government has also requested, though not required, that milk from Fukushima province should not be shipped.

Chief cabinet secretary Yukiyo Edano, announcing the measures, stated yesterday that it was perfectly safe to consume the named products, in which very low levels of radioactive iodine and caesium had been found.

Analysis

This seems very credible. Based on experience from Chernobyl the only possible public danger is that from the radioactive isotope iodine-131. Children and young adults who ingested small amounts of this in milk during the weeks following the Chernobyl incident subsequently had a very slightly enhanced risk of thyroid cancer even though they had never been exposed to dangerously high radiation levels: this was because the body, especially if one's diet is low in salt, takes up iodine and concentrates it in the thyroid gland.

Colossal amounts of iodine-131 were hurled high into the atmosphere when the Chernobyl core melted down, burst open, blew up and then burned while molten and open to the sky for days on end. It's now thought that some 18 million youngsters across the region consumed dangerously contaminated milk as a result, containing iodine levels thousands of times higher than those seen now in Japan, and that as a result their chance of getting cancer increased from say 25 per cent (or whatever it would normally have been) to 25.02 per cent. Death rates didn't rise correspondingly as thyroid cancer can normally be cured.

This remains the only radiological effect of the Chernobyl disaster on people outside the plant itself, though so many scare stories were and still are circulated about it that one will still be subjected to a barrage of abuse for saying so. It is now an officially acknowledged fact that the great bulk of medical damage to the public after Chernobyl resulted from mass panic and associated psychological stress, not from the accident itself.

Nuclear 'stress tests'? What, like hitting an obsolete plant with a massive disaster far beyond what it's meant to take, you mean?

The cores at Fukushima have remained sealed inside thick metal and concrete barriers, and while they have suffered some heat damage they have not melted down, far less been on fire, melted down and laid open to the sky as with the case of the core at Chernobyl. Tiny amounts of iodine-131 have escaped carried by cooling steam.

According to the Japanese health-ministry calculations, one would need to consume food containing iodine-131 in the levels so far seen for 14 years before you had even the tiniest increased chance of cancer. You couldn't possibly do that, as iodine-131 has not been generated at Fukushima for eight days – since the cores scrammed as the quake hit – and it only has a half-life of eight days. It will have declined to negligible levels within weeks no matter where it is – in a cow, on a spinach leaf, in your body, wherever. (One should also note that the spent fuel rods in the pools, not having undergone fission for months, don't have significant amounts of iodine in them.)

Against this background the initial Japanese decision to do nothing at all about food shipments looks like the correct one. Unfortunately public hysteria has been fanned by ridiculous statements from overseas and UN officials, forcing the present limited climbdown.

Barring some new and unforeseen event at the powerplant, it seems clear that there will be no measurable radiological effects on anybody as a result of the quake and tsunami. Unfortunately the psychological consequences – almost entirely a result of fearmongering and bad reporting in the media worldwide – seem set to be measurable. Mainstream media finally have some decent analysis here and there, but every minor development in the case is still reported on breathlessly, in a panic-stricken tone. Even those who seek to give a calmer view are still, a week after the quake, writing things like this:

Those at real risk now are the truly brave technicians inside the plant trying to cool it down: the Fukushima 50.

They will almost certainly receive fatal doses of radiation as they work around the clock.

No, they won't: nor even such doses as to measurably affect their health. Nobody else looks to be affected either. But the hysteria seems set to go on and on, even among relatively impartial and calm-minded observers – who remain rare. Asinine talk of an "apocalypse" and a "situation out of control" by the EU Energy Commissioner has drawn condemnation even from the French – who themselves have been guilty of inflating the seriousness of the Fukushima situation over recent days. (One can't help noticing that Japan is perhaps the main competition facing France in the export market for new reactors, potentially enormous in coming decades.)

We hear now that Europe is to "stress test" its reactors, and moratoria and safety reviews are to begin in nuclear-powered nations around the world. But any rational observer would have to conclude that reactor technology has just suffered the most severe stress test imaginable, and come through with flying colours in the worst possible situation: aged reactors hit by a natural disaster of unprecedented, colossal scale. The situation really calls for a reduction in nuclear safety bureaucracy, not an increase.

That would be worth doing, too. Suppose that nuclear power were allowed to be merely, say, 100 or 1,000 times safer than coal or oil (or wind: wind power has already caused scores of deaths in a brief period while at the same time generating very little energy). In that case nuclear would become so cheap as to wipe out carbon emissions and other pollution from electricity production in the advanced nations – and it might also start to make serious cuts into emissions from other sectors such as transport, heating etc, as electrical heat became cheaper than that from gas or oil and cheap juice drove down the expense of EV charging infrastructure.

Even some really hard-green commentators are starting to realise this, as they look into the reality of Fukushima. Meanwhile, even committed carbon sceptics often to be found at the opposite end of the political spectrum (or maybe off at the side somewhere) might yet relish a future in which the free world cared nothing for the price of oil or gas, nor for the opinion of sometimes unsavoury foreign governments on whose territory the supplies are mostly found.

Everyone might prefer a future in which less was spent on energy overall, and in which the money so spent shifted heavily towards well-paid skilled jobs at home and out of big profit margins for otherwise unimportant tyrannies around the world.

The possibility remains there for the developed world to move to a vastly superior future which would please almost everybody: greens; energy-security hawks; those primarily concerned about economic health; and those who worry about social justice and wealth distribution and provision of good well-paid jobs (the unions, unsurprisingly, love nuclear).

But that better future seems set to be denied to us by the effects of fear and ignorance, driven irresistibly forward by standard-format journalism. ®

Bootnote

Normally we here on the Reg science desk would have dropped this story days ago – it refers to a very minor aspect of the quake and tsunami disaster, with zero human consequences in and of itself. But the accompanying panic has become a story in its own right, threatening to harm millions and shift government policies disastrously.