Radiation – can allies be found in nuclear medicine?30 January 2015 by Steve Kidd
It is the responsibility of the nuclear industry, not regulators, to fight for reform of the radiation protection system. The problems being faced are similar to those likely to be encountered shortly in the medical profession.
In my November article (Radiation - how can the industry begin to deal with its biggest challenge?) I highlighted the need for the Linear No Threshold (LNT) theory of radiation exposure and consequent harm to be rebutted and for this to quickly become part of public policy. This is particularly so in the case of severe accidents such as at Fukushima. One suggestion was that the nuclear power industry may find some allies in the field of nuclear medicine, which appears to be coming under increasing attack for the level of radiation exposure resulting from some procedures.
[Cartoon by Alexey Kovynev: "Problem with the nuclear plant?" "No! Great problems with the regulator"]
Very high doses of radiation, commonly in excess of 40,000 mSv per month, have been in use for over a century to cure cancer, largely resulting from the original work of Marie Curie. This is generally accepted today, although the energy deposited in therapy is not confined to the tumour. Over the course of treatment, nearby healthy tissue will also receive huge doses and there is undoubtedly a risk (some put this at 5%) of it contracting a new primary cancer. Nevertheless, this is regarded as a reasonable risk, given that the patient would otherwise probably quickly die from the identified cancerous tumour. Yet these doses are orders of magnitude greater than the limits under discussion with regard to both nuclear power and medical x-rays and scans, which are only between 1 and 20 mSv per year.
There have, however, been several recent reports claiming significant dangers for patients receiving low doses within the medical sphere, and these have attracted widespread attention. In January 2014, the New York Times carried an op-ed article entitled 'We are giving ourselves cancer', which claimed that the frequent use of medical imaging techniques (particularly CT scans) in the United States was causing many thousands of additional cancers.
The effective dose from an abdomen and pelvis CT scan is about 10 mSV while that for a mammogram is about half of this. Reading the article one is struck by the similarity to the analyses of the Chernobyl accident by anti-nuclear elements, particularly the claims of many thousands of deaths. These high numbers are arrived at by applying some very low, purely theoretical, calculations of risk to a large population, the so-called Collective Dose Hypothesis. This is now generally discredited as a useful tool, but sounds reasonably logical until you think about it carefully. While it is undoubtedly true that there are probably too many scans ordered on a routine basis (there are commercial pressures in the US medical system encouraging this) there are clearly big benefits in early identification or clarification of medical problems. This tends to be the argument put forward by the medical profession. For example, the website of the UK National Health Service (NHS) concedes that there are indeed some small risks involved in scans, but these are vastly outweighed by the medical benefits.
This has tended historically to be similar to the stance adopted by the nuclear power industry. Yes, it is accepted that there are small risks from low levels of radiation, but they are outweighed by the benefits of nuclear power. Yet history shows that this is a very dangerous road to go down. Many people around the world have begun to reject nuclear power as they no longer accept the bargain. It is surely only a matter of time before the medical profession faces the same problem.
Another area that has come under attack is the administration of x-rays in dentist's surgeries. Patients note that dentists and their technicians usually step out of the room while the procedure is carried out but can rationalise this because the professionals' exposures could no doubt accumulate to very high levels through administering several x-rays each working day. More worrying is the common procedure of draping a lead-lined apron over the patient's body to protect the vital organs, particularly as this doesn't protect the brain and it's (perhaps not surprisingly) now being argued in studies that patients receiving a lot of dental x-rays are subject to a slightly higher risk of developing a brain tumour. There are of course lots of studies and their authors are always trying to get their most startling conclusions covered by the BBC or well-respected newspapers, but they have an impact. Even if they are subsequently heavily-criticised by other scientific authorities, many of the general public tend to believe what the BBC or New York Times says first.
So far at least, the attack on medical imaging hasn't gone as far as against nuclear power. The commercial interests that would be under threat haven't woken up to the fact, or are just keeping quiet. There are huge companies such as GE Healthcare involved in supplying the expensive equipment, but they may well be loath to associate with nuclear power, fearing a possible "guilt by association". Yet surely it is only a matter of time before both sectors will be facing an identical situation, which can only be overcome by having a much better public understanding of low levels of radiation and achieving official standards fixed to cover the negligible risks in a more appropriate manner.
Advocates of both cannot realistically justify the activities by saying that the benefit outweighs the risk. They have to convince the public that the risk is essentially nonexistent. Rather like the airline captain mentioned in last month's article. When you board his plane, if asked, "Is it safe to fly with you," he will say, "Of course" and not, "Yes, but..." Despite huge publicity about every major crash, the overwhelming majority of the public accepts that it is safe to fly and don't much worry about it. This is essentially where they are with medical scans today - people accept the doctor's word that it is safe and only if they question this (or look on the NHS website) will they encounter the back-up argument that the benefit easily outweighs any risk. But with nuclear power, most people are already worried that it is intrinsically unsafe and may not be convinced by the avowed benefits.
Having conceded the ground on low doses of radiation, and allowing the LNT to impose stringent requirements on the industry, the approach has been to stress all the avowed benefits of nuclear. So despite one major accident every 20 years or so in which thousands of people will be evacuated and many will die prematurely (not because of the radiation, but because of the psychological impact of being forced away from home), nuclear is still apparently deemed acceptable. Nuclear produces huge quantities of power at a steady rate, providing security of supply, lower dependence on imported coal and gas and at a low production cost. On the environmental side, nuclear has obvious benefits when it comes to greenhouse gas emissions and this has arguably become the biggest selling point today.
Unfortunately this will never be enough to overcome the fear factor that has blighted the recent history of nuclear power. And the industry has merely sat back and allowed this to happen. Belatedly, some nuclear advocates have noticed this and have begun to argue for a complete reform of the radiation protection system. Their approach is to argue that the health, safety and environmental (HSE) challenges facing the world are huge and that exposure to radiation is both local and inconsequential. Big problems such as climate change, air pollution, water pollution, industrial blight and urban sprawl are much more significant and should be treated first. The big problem is lack of coordination of national and international agencies to give balanced assessments of total risks and rewards, leading into sensible public policies.
Life cycle analyses of various energy sources show that nuclear holds a very strong position, having a very minor environmental impact. Yet this is not reflected in the way it is treated, with unbalanced radiological protection policies on the control of very low public exposures to radiation. The rules that are imposed negatively impact nuclear across the board, for example in licensing, discharges, storage, transport and waste disposal, adding significantly to costs. We can particularly see this in the costs of licensing complexity and construction delays for nuclear. Arguably a significant part of the problem of nuclear plant cost escalation can be attributed to this. The principle in regulation seems to be to put big controls on nuclear power as standards only apply to those radiation sources "amenable to control" - regulators concentrate on what can be regulated and arguably ignore much more. Medical and background exposures for the average person are far higher. The regulators know that with improvements in nuclear technology, exposures can theoretically be cut even further but these will be even more expensive. And nowhere is there a proper cost-benefit analysis of whether this makes sense, while it would almost certainly be better to concentrate resources at making improvements in other areas.
The only reason that nuclear radiation is treated exceptionally is historical, and with examples like the Fukushima evacuations, this continues to cause great suffering and loss of life. What the world needs is education about radiation, not regulation. But who is going to do this?
The root of the problem lies not with regulators. They essentially do what they're told by the radiation health physics community. These are the people who have really fouled up over the years. Of course they claim that they were only protecting the public, but their failure to put the risks of low levels of radiation within the wider context of other risks within society is patently obvious. Those working within the industry are particularly culpable - one cannot expect the professionals sent by countries to international meetings to stick up for the industry. Meanwhile, the International Atomic Energy Agency (IAEA) hides behind the LNT orthodoxy partly because it's easy and partly because too many bureaucratic careers would be threatened if the paradigm were overthrown. The impact is that the nuclear industry now faces a monumental problem and it is frankly hard to see it getting overcome.
Clearly a major contributor to the damage caused by any industrial accident like Fukushima is the potential for irrational response from governments and institutions, a factor frequently overlooked in safety studies. We consider the possibility of operator error, but we do not consider the potential idiocies of regulators and politicians. It is not better to preserve the lives of persons by being conservative in the level of radiation exposure - there is no place for a precautionary principle. Rather than the industry having to show that there is no impact from low radiation doses, the onus should be to prove some degree of harm at some given dose. So the question is: at what point do we acknowledge that "conservative" means killing people, real people and not mere statistics? This is indeed what happened as a result of the excessive evacuation orders by the Japanese government in the wake of Fukushima. In short, how do you contrast real, demonstrable casualties today against theoretical ones tomorrow? Particularly when the theoretical casualties tomorrow are based on a statistical projection without supporting evidence?
What is clear is that the representative bodies of the nuclear industry, such as the World Nuclear Association, Foratom and the national associations and institutes, are not doing nearly enough on either educating the public about radiation or fighting the case to get LNT overthrown. They need to devote a far higher proportion of their resources to this or else the industry will slowly disappear into the sunset, as older plants get shut down and new ones are not built. It is clear that the industry needs professional help from outside to help in this but the main thing it needs is the will to succeed and to stop wasting resources on other worthy, but less important activities.
About the author
Steve Kidd is an independent nuclear consultant and economist with East Cliff Consulting. The first half of his career was spent as an industrial economist within British industry, followed by nearly 18 years in senior positions at the World Nuclear Association and its predecessor organisation, the Uranium Institute.