Fukushima! Scary! Pacific dead! We’re all going to die!

Lately I’ve been amazed at the level of ranting on youtube. Ranting about a very GOOD and helpful NOAA map that saved lives. Is this a map of radiation spreading out of Japan? Hint: what does the legend indicate?Energy_plot_japantsunamiThat’s right, it’s the NOAA tsunami warning system and the legend clearly says (cm) in black on the sidebar, not mSv or some other radiation nomenclature. Yet youtube is full of misguided anti-nuclear activists sadly ranting into cyberspace ignorant bile about “The Pacific Ocean is dying!” etc. Indeed, the ocean is in serious trouble from climate change, pollution, plastic, fertilisers, dead-zones, over-fishing, all of which I have briefly documented on this blog. But not so much from radiation. See, water itself blocks radiation, and halves the effect of radiation every 7cm! Within a few meters even the nastiest radioactive waste is negated. A fish would have to swim right over a particularly concentrated patch of our vast, vast oceans to be hurt, and even then might be gobbled up before it could mutate into Godzilla.

In fact, water is so good at stopping radiation you would swim through a reactor pond! As long as you stayed away from the deadly nuclear waste at the bottom of a storage pond, and swam through the middle, you would experience less radioactivity than here on the radioactive surface of the earth because the water above you would shield you from cosmic rays and this radioactive old planet we live on!

Not only this, but many reports panic about tritium water leaking out of storage tanks. Really? If it was a choice between spending money cleaning up some really nasty waste like Caesium 137 or tritium water, I say let the water flow!

As the Environmental Protection Agency says:

“How does tritium affect people’s health? As with all ionizing radiation, exposure to tritium increases the risk of developing cancer. However, because it emits very low energy radiation and leaves the body relatively quickly, for a given amount of activity ingested, tritium is one of the least dangerous radionuclides. Since tritium is almost always found as water, it goes directly into soft tissues and organs. The associated dose to these tissues are generally uniform and dependent on the tissues’ water content.”

In other words, you can drink it and not die. Not so with certain other nuclear wastes that we really should be mopping up from Fukushima, quickly!

There’s also panic about slightly increased tiny levels of background radiation around Fukushima, influenced by Dr Helen Caldicott screeching “THERE’S NO SAFE LEVEL OF RADIATION!” For instance, this piece by the Physicians For Social Responsibility no doubt means well, but it says:

In November 2011, the Japanese Science Ministry reported that long-lived radioactive cesium had contaminated 11,580 square miles (30,000 sq km) of the land surface of Japan.[i]  Some 4,500 square miles – an area almost the size of Connecticut – was found to have radiation levels that exceeded Japan’s allowable exposure rate of 1 mSV (millisievert) per year.

About a month after the disaster, on April 19, 2011, Japan chose to drastically increase its official “safe” radiation exposure levels[ii] from 1 mSv to 20 mSv per year – 20 times higher than the US exposure limit.  This allowed the Japanese government to downplay the dangers of the fallout and avoid evacuation of many badly contaminated areas.

20 times higher than the US exposure limit! Government downplaying dangers! Oh the conspiracy! Oh the humanity! Run for the hills! But wait a minute. What is a mSv per year anyway, and how much exposure is allowed in American nuclear workers. Forget that, what about nations that might live on tops of mountain ranges or high plateaus, and get less atmospheric protection from the sun and cosmic rays? What about Kerala India that has 30 million people living in higher radiation regions because of above average thorium in their soils? What about them? As the Charles Sturt University: Radiation Safety Committee says,

10,000 mSv (10 sieverts) as a short-term and whole-body dose would cause immediate illness, such as nausea and decreased white blood cell count, and subsequent death within a few weeks.
Between 2 and 10 sieverts in a short-term dose would cause severe radiation sickness with increasing likelihood that this would be fatal.

1,000 mSv (1 sievert) in a short term dose is about the threshold for causing immediate radiation sickness in a person of average physical attributes, but would be unlikely to cause death. Above 1000 mSv, severity of illness increases with dose.
If doses greater than 1000 mSv occur over a long period they are less likely to have early health effects but they create a definite risk that cancer will develop many years later.

Above about 100 mSv, the probability of cancer (rather than the severity of illness) increases with dose. The estimated risk of fatal cancer is 5 of every 100 persons exposed to a dose of 1000 mSv (ie. if the normal incidence of fatal cancer were 25%, this dose would increase it to 30%).

50 mSv is, conservatively, the lowest dose at which there is any evidence of cancer being caused in adults. It is also the highest dose which is allowed by regulation in any one year of occupational exposure. Dose rates greater than 50 mSv/yr arise from natural background levels in several parts of the world but do not cause any discernible harm to local populations.

What? 50 mSv a year, over 70 years = 3500 mSv, and there’s no increased cancer rates? But Japan has this huge government conspiracy ‘downplaying dangers’ when they increased their exposure limits to TWENTY TIMES THE US LIMIT! Basically it seems that world governments and authorities have responded to the ‘no safe level of radiation’ meme promoted by Dr Helen Caldicott when the reality about tiny little levels of radiation is… we just don’t know! At this stage, the No Linear Threshold model is just that, a mathematical model. Big dangerous levels of radiation have obvious consequences, as we saw above. But slightly increased levels of radiation may actually stimulate the body to respond to genetic abnormalities and mop them up, a little bit like vaccines teaching the body to respond to bad flu strains.

Once again, we see smart people writing stupid things. I have no doubt that the author at Physicians for Social Responsibility wants to help people. But he’s influenced by FUD, Fear, Uncertainty, and Doubt. The peer-reviewed evidence is out on slightly increased levels of tiny radiation. Indeed, there may even be evidence that slightly increased radiation is good for us! There is an article from The Breakthrough Institute that has the following amazing headings about Fukushima:-

1. Thyroid Cancer Rates Lower in Fukushima Children Than Other Regions

2. Fukushima Seafood Safe to Eat

3. Fukushima Evacuation Zone Is Mostly Habitable

4. Cancer Rates in USS Reagan Crewmembers Lower Than Control Group

5. Fukushima Death Toll Is Too Small to Measure

Please read the article! Rather than run around screaming about Fukushima, maybe the Japanese should move back and live there and the rest of us should get over it. Just living there, doing the normal urban things us humans do, like demolishing old places, rebuilding new ones, gardening, mowing laws, etc, will diffuse the radiation and maybe wash some of it down into the ocean where the water’s halving-every-7cm rule takes over.

But not so fast! Let’s assume that Dr Helen Caldicott is right, and that one day science will actually catch up with her ‘methods’. Let’s assume there is No Linear Threshold, no safe barrier, and that even tiny increases in radiation will actually result in tiny increases in cancer rates. (Even though George Monbiot has shown that Helen’s books are largely self-referencing and fraudulent). What if she’s right?

Pro-nuclear author Mark Lynas assumes the NLT model and goes on to explore what that might mean for the Japanese people.  It seems to be a choice between massive mental health issues for the evacuees, with all the associated depression and increased suicide risks, and a slight increase in possible cancer rates. Let’s remember that climate change is ticking along, and could end up killing hundreds of millions or billions if it forces us to war. Let’s also remember that medicine is galloping along towards a cure for cancer that could arrive in the next few decades. And let’s think mathematically, statistically, about large population groups and what is best for the nation. I’ll finish by handing you over to Mark.

For the purposes of argument, therefore, if everyone living in the exclusion zone (and other severely-contaminated areas) could be persuaded to give up driving (and to eschew smoking, which presents a massive lifetime risk of 100 in 1000 of causing lung cancer) then everyone could in theory be allowed to return with no additional loss of life to the impacts of radiation. The risks could simply be traded off each other. One could also make a strong case that people living in the Fukushima exclusion zone would still be better off statistically than those in heavily-polluted city centres, near coal-fired power stations and in industrial zones, which likely present higher carcinogenic risks.

Indeed, these risks were quantified and compared in a fascinating 2007 paper published in BMC Public Health journal (open access, h/t ColinG, [x]). In it the author looks at the comparative risks of obesity, smoking and exposure to radiation – in terms of ‘years of life lost’, a male smoker can expect to lose 10 years of life, an obese white male 1-4 years of life, as compared to an average 2.6 years of life lost for Japanese atomic bomb survivors who had experienced the highest doses (2.25 Gy – for gamma radiation such as released by an atomic bomb, sieverts and grays are roughly equivalent, so the dose can be thought of as 2,250 millisieverts; about ten times higher than current doses anywhere in the Fukushima exclusion zone).

An equally useful comparison made by the author considers whether air pollution in city centres, passive smoking or radiation contamination from the Chernobyl accident are more dangerous. He finds that living in a polluted city (e.g. London, as compared to lightly-polluted Inverness) yields 2.8% mortality (28 per 1000), passive smoking 1.7% mortality, whilst radiation exposure of 100 mSv in the Chernobyl zone yields a mortality risk of 0.4% (4 per 1000). This latter risk is clearly on the same scale as the US scientific committee which calculates a 3-7 per 1000 risk of mortality for 100 mSv, and obviously compares rather favourably with the 28 per 1000 mortality risk for living in a polluted area. This raises the intriguing possibility that – if these calculations are correct – lives would be saved by moving people out of central Tokyo and into the more contaminated areas of the Fukushima exclusion zone.

This is in fact exactly the conclusion reached by the paper’s author:

The increased mortality rate of the populations most affected by the Chernobyl accident may be comparable to (and possibly lower than) risks from elevated exposure to air pollution or environmental tobacco smoke. It is probably surprising to many (not least the affected populations themselves) that people still living unofficially in the abandoned lands around Chernobyl may actually have a lower health risk from radiation than they would have if they were exposed to the air pollution health risk in a large city such as nearby Kiev.

Of course, real people do not base their risk assessments on scientific numerical quantifications such as this. There are also ethical issues in that obesity or living in a polluted city can be considered a personal choice, whilst having a nearby nuclear power station suffer a triple meltdown is something imposed on a population not used to such a danger. But the trading-off of risk is unavoidable, and the experience of Chernobyl shows that permanent exclusion from their homes and communities is also extremely damaging to people’s health, and increases mortality rates from ‘lifestyle’ causes such as suicide, alcoholism and so on. In addition, when people are labelled ‘victims’ and told they are doomed to die of cancer, an increased number may indeed suffer a psychologically-induced ill-health.

Naturally it will be extremely difficult for the Japanese authorities to make a decision about how far to relax the exclusion zone that has been set up (though the process of reaching this decision has already been cautiously begun[xi]). People are terrified of radiation – far more terrified than they are of traditional sources and activities which present a much greater statistical risk of causing cancer – and the activities of anti-nuclear campaigners in the area has doubtless increased this sense of terror. It has also added to the distrust of experts in general and the government in particular, despite the need for decision-making to be based on a scientific approach to real risk rather than the terrors imagined by an already-traumatised population.

In the final assessment we also need to remember the wider catastrophe of March 11 of which the nuclear disaster is only a small part. More than 20,000 people died as a result of the tsunami, and none have so far died or been injured because of the events at Fukushima Daiichi. I hope also that the continuing media and official attention being given to the nuclear crisis does not distract from the needs of those displaced (also perhaps permanently), bereaved and traumatised by the tsunami. And, as I have argued elsewhere, it is equally important that the accident at Fukushima does not lead to a hasty abandonment of nuclear power both in Japan and other countries, resulting in a return to the vastly more dangerous energy source of coal. For the sake of all those affected by this desperately unfortunate sequence of events, the Japanese government must continue to take a rational approach to risk, build up the trust of its people and resist the demands of both media hysteria and ideological campaign groups.

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