Monday, November 26, 2012

Coal, mercury and green hypocrisy

 One of the things that pro-nuclear advocates find so irritating is the obsession on the part of many with nuclear waste, as if the waste products from nuclear power were in some way more toxic or uncontrollable than other kinds of industrial waste.

Mercury that is released into the atmosphere becomes methylmercury that is easily absorbed by plankton in the oceans and works its way up the food chain through the process of biomagnification. At each stage in the food chain the mercury is concentrated more and more, so that end stage predators such as swordfish, shark and tuna can sometimes have toxic levels of the element in their flesh. This can cause a serious problem, especially for pregnant women. In the U.S., the largest single source of mercury contamination is the coal industry.

While this is a serious environmental problem it is never accorded the same danger status as minute amounts of nuclear contamination in the flesh of seafood, far too low to actually cause illness to humans, and in fact only detectable because the instruments that can detect the contamination are extraordinarily sensitive. This is the case for various fish catches around the Pacific that have minute levels of caesium that have been attributed to the Fukushima accident.

While reports of radioactive contamination in fish invariably elicit reactions of horror, contamination by mercury while acknowledged as dangerous is considered to be much more routine. In the movie The Cove, which critically examines the dolphin hunting industry in Japan, this mercury contamination is continually mentioned as a reason for humans to avoid the consumption of dolphin meat. Yet the source of the mercury is not mentioned, let alone the only real alternative to this constant release of mercury into the environment, which has to be nuclear power.

I very much doubt that the people who made The Cove (or indeed, many of the people who saw the movie) are realistic about the implications of their obsession with mercury. If followed to the rational conclusion, if indeed people have the goal of reducing the danger of pollutants in the atmosphere and oceans, it is inevitable that the best way to do that is to replace coal power with nuclear.

Friday, November 23, 2012

Letter to the Prime Minister of Japan!

Dear Prime Minister Yoshihiko Noda,

For the sake of Japan, and for the sake of the world, I implore you to consider the issue of nuclear power in the spirit of moderation and reason, and resist efforts by the anti-nuclear lobby and elements of the media to promote fear and panic.

The most false and distressing of the efforts is the attempt to conflate the peaceful use of nuclear power with the terrible atomic bombings of Hiroshima and Nagasaki at the end of World War Two. The events are incomparable, as is clearly showed by the human cost. On the one hand, over 100,000 people were killed by the Hiroshima blast. On the other, nobody has been killed or injured by the Fukushima accident. Yet an extraordinary example of this propaganda was published by the Japan Times’ Hotline to Nagatacho on the 9th of October, when the article, incredibly, decried the reopening of schools within the former evacuation zone, protesting at the temerity of people wanting to return to their homes, reform their communities and start the rebuilding of their lives. The author, who didn’t deign to offer anything as prosaic as radiation measurements, implied that the children going to the schools would suffer the same fate as the children of Hiroshima sixty-seven years ago!

It is well-known that low dose radiation is of zero or negligible risk to humans, yet the unwarranted fear of radiation is destroying the future of Japan.

A clear example is the Nuclear Regulation Authority’s decision to expand the evacuation zone around nuclear power plants to 30 km, massively compounding unnecessary fear and sending municipalities nationwide into a frenzy of useless planning. Was it not enough that 573 people died because of unnecessary and panicked evacuation after the Fukushima accident, including dozens of elderly patients simply abandoned in hospital to die a degrading death? Not only that, but the NRA is said to be considering expanding the definition of an active earthquake fault line to one that has moved within the last 400,000 years, thus putting into doubt the restarting of nuclear plants all over the country. Is it really possible that humans could be so foolish as to curtail a vital economic activity at a given site because of the hypothetical risk of an earthquake every 400,000 years?

The linking of the use of nuclear weapons with last year’s accident at Fukushima is specious. It is also unethical. Yet ironically, there is a useful lesson to be learned in this attempt at conflation by the anti-nuclear lobby. It reveals the real source of public anti-nuclear sentiment – an unconscious equivalence of nuclear power with the destructive terror of nuclear weapons. Never mind that when considered rationally, nuclear power is the safest large-scale source of energy available to humanity. Never mind that nuclear energy is incomparably healthier than energy produced by fossil fuels, or that it is vastly cheaper and more reliable than renewable energy or that it produces close to zero CO2 emissions. Never mind those things; because at some deep level of the public’s unconscious nuclear power equals terrible danger.

Mr. Prime Minister, the government has the right and indeed the duty to make decisions based on science and reason, and not be swayed by the irrational. The fear of radiation is a phobia that defies reason, and rather than pander to this fear Japan should recognize the advantages of nuclear power and continue its steady expansion. The benefits are undeniable and the bulk of the criticism it attracts is simply ill-founded. To paraphrase the words of American liberals, reality has a nuclear power bias.


Saturday, November 10, 2012

Evidence for Linear No-Threshold Theory?

A new study has just been released that casts doubt on the theory of radiation hormesis, the idea that low doses of ionizing radiation can be good for you. It seems to provide some evidence for the Linear No Threshold theory, which assumes that cancer risk is directly proportional to the amount of radiation taken in, so that there will always be some risk, even as very low doses. What this theory means is that while the risk for the individual may be very low, over a large number of people there will be some cancers that are induced by radiation.

The model has always been controversial, and extremely difficult to measure, because at such very low levels of risk it is difficult to separate confounding factors in statistical studies. Even things like different populations being more reliable in self-reporting smoking rates can confuse things so that results are not reliable.

This Linear No-Threshold Theory (LNT) has always been doubted by pro-nuclear experts. After all, what other substance in the universe has new threshold for effect? Even poisons like arsenic have a minimum does below which no effects at all can be expected. Wade Allison sums up this skepticism:

"In earlier decades knowledge of cell biology was too primitive to provide confident understanding, and adequate evidence of the effect of radiation on humans was no available to corroborate any particular view. In their absence, and for lack of anything better, the knowledge gap was bridged by a rule of thumb - a model in science speak. This is the LNT model. This assumes that clinical damage is in simple proportion to the initial radiation energy dose. No justification was given for it, but it was a reasonable working hypothesis at the time. Despite the poor state of knowledge, a start had to be made somewhere."
(From Radiation and Reason, p. 44)

Now the most rigorous support for LNT, at least to my knowledge, has come in the form of a study of 110,645 people involved in the cleanup after Chernobyl. It concluded that despite the relatively low doses of radiation received, there was a significant increase in the risk of getting leukemia.

We are talking about a very small number of cases, 117 cases of leukemia. It was estimated that 16% of leukemia cases were attributed to radiation exposure, that is, 19 cases. The cleanup workers also received considerably more radiation that residents of Fukushima. Just to put this in perspective, 19 cases is 0.0019 % of the deaths that can be attributed to coal dust every year.

Nevertheless it has thrown the pro-nuclear community into a bit of a tizzy. Any evidence for LNT will be more fuel for people who say that any level of radiation is dangerous. The inevitable claim will be that there is actually some risk for people up at Fukushima. If you crunched the numbers you might come up with 2 or 3 cases of leukemia, at a guess.

You can read the paper here. If it is deliberately anti-nuclear, it is massively more sophisticated that the propaganda put by Arnie Gundersen or Helen Caldicott.  Certainly it is beyond my skill set to critique.

You can read an early response by a pro-nuclear blogger here. I will be watching carefully how this all goes down