Fukushima children condemned

SUBHEAD: Cancer risk to young children near Fukushima Daiichi vastly underestimated by Japanese.  

By Arnie Gundersen on 17 January 2012 for Fairewinds Associates- (http://fairewinds.com/content/cancer-risk-young-children-near-fukushima-daiichi-underestimated)
Image above: Childen of Fukushima receive their radiation dosometers. From (http://japan.resiliencesystem.org/fukushima-children-receive-radiation-meters).

Fairewinds analyzes cancer rates for young children near Fukushima using the National Academy of Science's BEIR (Biological Effects of Ionizing Radiation) VII Report. Based on BEIR VII, Fairewinds determines that at least one in every 100 young girls will develop cancer for every year they are exposed to 20 millisieverts (2 rem) of radiation.

The 20-millisievert/year figure is what the Japanese government is currently calculating as the legal limit of radiological exposure to allow habitation of contaminated areas near the Fukushima Daiichi nuclear power plant. In the video below, Fairewinds introduces additional analysis by Ian Goddard showing that the BEIR VII report underestimates the true cancer rates to young children living near Fukushima Daiichi.

Looking at the scientific data presented by Mr. Goddard, Fairewinds has determined that at least one out of every 20 young girls (5%) living in an area where the radiological exposure is 20 millisieverts for five years will develop cancer in their lifetime.

Video above: Arnie Gunderson introduces film by Ian Goddard on statistics regarding populations exposed to low level long term ionizing radiation. From (http://vimeo.com/35212151).  

Video Transcript
Following the Fukushima nuclear disaster, the Japanese Government raised the level of allowable radiation exposure from 1 to 20 millisieverts per year, even for children.

NHK: "On April 19th, the Ministry of Education, Culture, Sports, Science and Technology announced that the amount of radiation a child can be exposed to in one year is 20 mSv."

IAN: Officials proclaim that 20 millisieverts per year is safe, but is it? In this video we'll test the official claim of safety against established radiobiological science. The same science upon which the United States National Academy of Sciences predicts that 20 millisieverts of radiation will not only cause cancers all across Fukushima, but will primarily kill women and children.

In this video we'll also test the official claim of safety against recently published research, such as the largest study of nuclear workers ever conducted. Comprising over 400,000 workers from 15 counties, the study found increased cancer mortality among nuclear workers exposed to an average of 2 millisieverts per year. That's just one tenth of the allegedly safe 20 millisieverts per year allowed in Fukushima!

In this video we'll see that the public is being misled buy governments and major media into a false sense of safety regarding nuclear fallout, obstructing the ability of citizens to be fully informed so that we can make sound decisions that direct our democracies to safe-energy futures.

So stay tuned, as we cover all that and more.

United States National Academy of Sciences is a logical resource to consult about the state of radiation science. And the Academy regularly publishes reports on low-dose radiation risks. The reports are based on decades of epidemiological and radiobiological research from which risk-predicting models are built. The Academy's most-recent report provides both raw data and instructions so that you can apply their risk models to a wide range of exposure scenarios. With the Academy's report we can therefore find the cancer risk of 20 millisieverts.

This is the Academy's data table for estimated cancer cases caused by 100 millisieverts of radiation, stratified by age and segregated by sex. Highlighted in yellow are the predicted number of cases for All cancers per 100,000 persons. Immediately we can see that the risk of cancer uniformly decreases as age increases for both males and females. In other words, children are most vulnerable to radiation.

Plotting these data yields this graph. This cancer-risk graph keeps this shape irrespective of dose. This shape is therefore the face of radiation-induced cancer risk across the human lifespan.

Following the Academy's instructions on scaling the model to specific doses, the lefthand y-axis is re-calibrated to the predicted cancer cases caused by the allegedly safe 20 millisieverts. And here in turn are re-calibrations for 10 and for 2 millisieverts. According to the academy, there is no harmless dose of radiation.

Obviously 20 millisieverts is not safe! But what's most remarkable is that children, and most especially girls, are the most at risk of radiation-induced caner. In fact, girls are almost twice as vulnerable as same-aged boys, and a 5-year-old girl is 5 times and an infant female 7 times more vulnerable than a 30-year-old man. So girls bear the brunt force of radiation's impact on the human race. Consider what this says about the ethics of nuclear-energy advocates who are aware of this fact.

These data from the National Academy of Sciences are freely available to all major media and government officials. Yet rather than informing the public of the actual state of radiation science and the real risks of nuclear power, they lead us instead to believe that 20 milisieverts of radiation is either safe or its effects are a complete mystery.

CBS: "Residents traveled to Tokyo to protest after the government loosened safety limits despite the fact the long-term impact of low-dose radiation is unknown. The long-term impact of low-dose radiation is unknown."

IAN: Even worse than a failure to inform, major media lead the public to believe that scientific models of low-dose radiation risk, such as we've just reviewed, don't even exist. Yet outside the media's cocoon of blissful ignorance, science marches forward, further characterizing the risks of low-dose radiation. And the flow of incoming evidence published since the Academy's last report in 2006 suggests that the Academy's risk model is either accurate or may underestimate risk.

In 2007 the largest study ever conducted on occupational low-dose radiation exposure was published. The study contained over 400 thousand nuclear-industry workers from 15 countries. The study found a significant relation between radiation dose and cancer mortality.

The average period of nuclear-worker employment in the study was 10.5 years, and the average dose accumulated over those years was 19.4 millisieverts. This implies an average annual dose of 1.85 millisieverts per year. So with an allowance of 20 millisieverts per year, Fukushiman children may receive up to 10 times the dose rate associated with increased in cancer among adult nuclear workers.

To get a more-accurate estimate of the average annual dose, this data table showing the average-cumulative dose and years of employment for each country is useful. From these data we find that the average annual dose for the whole cohort was 1.95 millisieverts per year, again rounding off to 2 millisieverts per year. The data provided by the study also allow calculation of the median annual dose of the whole cohort, which was lower still, at merely 0.45, or one half of a millisievert, per year.

So the representative dose-rate among the nuclear workers was at most one tenth of the 20 millisieverts per year allowed in Fukushima. And yet that much-smaller dose over an average of 10.5 years is correlated with elevated risk of cancer mortality.

To get a sense of the distribution of exposures, 90% of the workers in the study received cumulative doses under 50 millisieverts over their entire period of employment, which overall was 10.5 years on average. So dividing 50 millisieverts by 10.5 years suggests that dose-rate for most of the workers was probably below 5 millisieverts per year, one forth of the maximum annual dose for Fukushimans.

To get a sense of the distribution of the radiation effect over the 15-country cohort, the authors eliminated each country from the study one at a time one to see if eliminating one country's data eliminated the indicated radiation effect. In each sub-analysis they found that the excess risk ratio, or ERR, was higher than, but compatible with, the National Academy of Sciences' BEIR VII risk model, which was the risk model we previously reviewed. So the indicated radiation effect was not biased by data from any particular country.

The authors of the study noted that worker smoking is a possible confounding factor since lung cancer was common among the workers. However, other smoking-associated cancers showed little relation to radiation dose and the authors concluded that even if smoking played a role, it cannot fully account for the dose-relation of cancer to radiation. So the possibly that cancer-correlation was actually an artifact of smoking does not appear to be the case.

So let's recap, the 15-country study authored by 51 radiation scientists, is the largest study ever conducted of nuclear workers; it found increased cancer risk among workers; the average worker dose was 2 millisiverts per year; most workers received under 5 millisiverts per year; and the maximum dose allowed in Japan is 20 millisieverts per year, 10 times higher than the average annual worker dose and 4 times higher than most worker doses.

Two years later in 2009, Jacob and colleagues analyzed the 15-country study we just reviewed plus eight other nuclear worker studies. What makes nuclear-worker exposure especially relevant to areas contaminated by nuclear fallout is that both exposure scenarios deliver doses at a slow persistent rate. And the meta-analysis of Jacob and colleagues suggest that such slow-dose rates might be more harmful than fast-dose rates.

For example, this chart from Jacob et al shows excess cancer-mortality risk found in nine studies of nuclear workers. Each study is denoted by a red dot whose rightward displacement from 0 risk along the bottom axis denotes the degree of increased risk found in that study.

In contrast, the blue dots represent the comparative excess risk among the atom-bomb-survivor cohort, adjusted to match the sex-ratio and average age of the nuclear workers in each study. As we can see, the red dots are usually more rightward displaced than the blue dots, and therefore most nuclear-worker studies found a higher risk of cancer mortality than among atom-bomb survivors.

This is a significant finding because radiation-risk models are largely founded upon fast-dose exposures like from the atomic-bomb blasts, and it had been assumed that fast-dose rates were more harmful. However, the findings of Jacob and colleagues bring this view into question.

As an editorial on the findings of Jacobs et al in the journal Occupation and Environmental Medicine, observed:

"a number of recent studies challenge the assumption that low-dose-rate exposures to penetrating forms of ionising radiation are less effective at causing cancer than high-dose-rate exposures." [because] "risk estimates for people who received low-dose-rate exposures tend to be larger than, or similar to, the corresponding estimates derived from the study of Japanese atomic bomb survivors."

This graph from Jacob et al demonstrates the discrepancy of risk models. The two leading risk models are on the left. The second is the National Academy of Sciences' cancer-risk model we examined previously. Both risk models are based largely on the fast-dose-rate exposure experienced by atomic-bomb survivors. But the third bar on the right represents higher level of risk derived from the slow-dose rate of nuclear workers.

So the cutting edge of meta-analytical research suggests that the leading contemporary radiation-risk models may actually underestimate the carcinogenic efficiency of low-dose radiation.

Science is not only further clarifying the harmful effects of low-dose radiation on large-scale macroscopic level but on the microscopic level as well. Recent research has increased the fidelity of data in the low-dose range regarding radiation-induced genetic damage.

Chromosomal translocations are a form of genetic damage resulting from faulty repair of DNA molecules damaged by genotoxic chemicals or radiation. Chromosomal translocations, also known as chromosomal aberrations, are believed to result in many forms of cancer. And an increased frequency of chromosomal aberrations is recognized as an indication of an increased risk of cancer. As such, radiation-induced chromosomal aberrations are fundamental to the causal mechanism of radiation-induced cancer.

It has been well documented that medium-to-high dose radiation increases chromosomal aberrations, but the influence of low-dose radiation has been less certain. But if this mechanism of radiation-induced cancer occurs at low doses, there would be little reason to doubt that low-dose radiation can cause cancer.

In 2010, Bhatti and colleagues published a meta-analysis of studies that examined the influence of medical X-rays examinations on the incidence of chromosomal translocations. They sought to gain greater precision on the impact of low-dose radiation by pooling data from multiple studies.

Not only did they find a dose-response in the low-dose range, but to their surprise the frequency of chromosomal aberrations per unit of radiation increased below approximately 20 millisiverts. Moreover, at doses below approximately 10 millisieverts the frequency of aberrations per unit of radiation increased further still, and by an order of magnitude. Given these findings, evidence for the carcinogenicity of radiation at low doses could hardly be more logically indicated. Let's examine this formally.

The Hypothetical Syllogism is a two-premise argument schema of classical logic of the form: Given that, if it's the case that P, then Q, and if it's the case that Q, then R, then we may conclude that it's also the case that if P, then R.

Plugging the scientific evidence we've just reviewed into the Hypothetical Syllogism we may reason: Given that, if there's low-dose radiation, then there's more chromosomal harm, and if there's more chromosomal harm, then there's more cancer, then we may conclude that if there's low-dose radiation, then there's more cancer.

Now, to some degree this syllogism may be an over simplification. The largely uncharted complexity of biological systems are not easily reducible to arguments of elementary logic. However, that said, our inputs into this valid argument schema are the outputs of state-of-the-art biological research, so the conclusion at this point in time appear to at the least be plausible.

In this video we've reviewed both established radiobiology and recent radiobiological research. From this broad scientific base we've observed that

The National Academy of Sciences predicts increased cancer risk from exposures below 20 mSv/y.

Research published since the Academy's last report in 2006 corroborates that prediction.

Recent research also suggests the Academy's risk model may underestimate cancer risk.

Recent research also finds that radiation exposures below 20 mSv are associated with genetic damage.

Therefore, both historical and cutting-edge scientific research consistently demonstrate that Japan's allowance of 20 millisieverts per year is not safe. .

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