Dr. Wade Allison taught and studied at the University of Oxford for over 40 years, where he is now an Emeritus Professor of Physics. His two books, Radiation and Reason and Nuclear is for Life, provide great introductions and references for those looking for a deeper understanding of how radiation affects the environment and public health.
We sat down to talk with him about the risks from overreacting to radiation fears, and how he views the state of the science and communication after the Fukushima accident.
What drove your interest in nuclear issues?
My career actually spans the whole of the nuclear period. When I was 13 on holiday in Europe with my parents in 1954, my sister and I got sick so we were driven to Geneva in case we needed a doctor. In the city there was a big exhibition, "Atoms for Peace 1954," and that was the occasion of CERN being founded. As a 13-year-old boy I was inspired and impressed by the reactor technology and what the possibilities were. So I went back to school and concentrated on science. I spent most of my career in particle physics and now I’ve come all the way back to the subject of that exhibition in 1954, the peaceful potential of nuclear power.
What brought you back to the potential of peaceful nuclear power you first saw as a boy?
Nearly 20 years ago I started giving a new final year student course in Oxford on applications for nuclear physics. I quickly got into medical physics and the course was rather popular with the students. It evolved more and more of a medical emphasis, including radiotherapy. That was when I saw the extraordinary difference between the high--but life-saving--radiation doses used routinely in medicine and the doses occasionally encountered in the environment.--many thousand times lower than medical doses. And I published a textbook for the student course that included a study of this comparison. The whole basis of current radiation safety regulation is crazy. We've got it all wrong. It was a big step for me to attempt an explanation of this for the unscientific public. Following a few popular lectures on the subject I started writing Radiation and Reason. Later, that got translated into Chinese and Japanese. After travelling to Fukushima, I began the second book [Nuclear Is For Life], which has a much broader scope than the first. It basically talks about how nuclear is positive, it is part of our natural environment and our cultural attitude is almost 180 degrees wrong. Nuclear radiation is almost completely harmless. Nowadays, I lecture around the world trying to get through to people, especially young people. They should put the legacy of the Cold War behind them. They need to look forward! But an important incident that I didn’t know when I wrote the first book was the accident at Goiânia in Brazil in 1987.
What happened at Goiânia, Brazil?
The radioactive contaminant of most concern at Fukushima was Cesium 137. This is produced in large quantities in any fission reactor, but it's also used prominently in radiation therapy. At Goiânia there was a radiation clinic that was abandoned. People broke into this facility and took the metal therapy unit with the Cesium inside it for scrap. This source of Cesium was 20 million million becquerels (Bq) which is orders and orders of magnitude higher than any contamination at Fukushima (100 becquerel is the legal limit in a litre of drinking water). So the source gave off a bluish hue and the local people were fascinated by it and played with it. By the time people started to get ill, 249 people were seriously exposed and about 70 were contaminated internally. The IAEA got involved and measured the contamination which was between a 1000 and 10,000 times larger than the largest dose recorded for any member of the public at Fukushima; truly colossal doses relatively. Four people died within the first few weeks, just as 28 firefighters at Chernobyl did. Others had serious skin burns but none of them died. In fact, in the following 25 years there were no further deaths that could be attributed to radiation--in particular, no attributable case of cancer.
I managed to contact the doctor in Brazil who was responsible for reporting on these patients to the IAEA in Vienna and he confirmed that in 25 years nobody got cancer from radiation. One woman was already pregnant when internally contaminated and another got pregnant five years later. Both children were measurably radioactive and yet are reported to be doing well. In the same way the wildlife in Chernobyl is thriving because the humans are gone and the radiation isn’t really harming them. In fact by driving the humans out the radiation at Chernobyl seems to have done the animals a favor.
You’ve written two books, Radiation and Reason and Nuclear is for Life, which deal with how society understands and interacts with radiation. What inspired you to step outside of the purely technical?
Because that’s where the problem is. The technical questions and the evidence that answers them are relatively straightforward but people's readiness to face them are not. I’m lecturing around the world trying to get through to people, especially young people. They should put the legacy of the Cold War that they have inherited from earlier generations behind them. They need to look forward
In Radiation and Reason, you say that when it comes to nuclear power, leaders “cannot instruct the court of public opinion” Why?
Leaders who stray too far from public opinion are soon out of power, in a democracy at least. At the moment the public still tends to see anyone who knows about nuclear technology as linked to the nuclear industry and so doesn't trust them. The people who really should know and be trusted by the public are the medics and academics (though most don’t). I’m retired and I have six grandchildren. When I went to Japan the local residents that I spoke to asked, “Who are you? How’d you get here? Did TEPCO or the government send you?” And I said, “No, I’m here because I have six grandchildren and I want them to live in a nuclear-powered world.” Then they started listening. Primarily the message needs to come from schools. But medical professionals should take a larger role. Anyone that undergoes radiotherapy gets a very large dose of radiation every day. People trust their doctors and these patients go home after successful treatment. Unfortunately, the use of radiation in medicine has been adversely affected by the connection with Fukushima so that some refuse the treatment they need. The positive message should be carried in the other direction: radiation in medicine is usually life-saving and the radiation doses at Fukushima were so low as to be totally harmless.
Is there a role for industry in this effort?
Well they’ve got to be very careful as the public doesn’t trust them. I don’t know whether it is true everywhere in the US, but until recently all the nuclear power stations here in the UK were closed to the public and they were closing their visitor centers too. “Open your visitor centers and let people in! Bring school children in!” I said. And they are doing that now. We can’t leave all matters with the nuclear power interests -- they are making a lot of their money from decommissioning the power stations that the environment needs to be kept working. In their defense, few in the nuclear power industry understand what I am saying and they don’t really like me. But we do need them back on track and building again.
Could you give a brief explanation of the Linear No-Threshold (LNT) model and its history?
In the initial fractions of a second after radiation hits living tissue, it easily smashes a few molecules and atoms because it is very powerful. As I describe in both of my books, the LNT theory is based on the assumption that there is no corrective mechanism for this phenomenon. The model assumes that life doesn’t do anything about the smashed molecules, which is only true of course for dead organisms. Living organisms maintain themselves. In fact for millions of years, in order to exist, life has lived with radiation. It has learned to either mend those molecules or identify and replace them, and all this happens automatically on the molecular level. It is a biological reaction that happens in all life. Now all that is ignored in the LNT model. It assumes that there is no correction and therefore the amount of damage is directly proportional to the amount of radiation received. It supposes the effect of exposure is cumulative. That leads to the safety concept known as ALARA, for which the exposure to radiation should always be As Low As Reasonably Achievable, i.e. completely avoided whenever possible. But in fact our bodies mend the damage as they go along. Radiotherapy wouldn’t work if it were otherwise. So a much more sensible idea is AHARS, or As High As Relatively Safe. In other words how high a dose can you receive without any harm.
What is the evidence that LNT is not the right model, can you give me a concrete example?
Radiation cures for cancer wouldn’t work if there were no correction mechanisms. Almost everyone knows someone who has had radiation therapy and knows that it does work. This does not come from the depths of a secret government lab, it's something that the majority of people have some familiarity with. The effect of continuous exposure to radiation below a certain threshold throughout life has been tested with dogs. Below a certain threshold there is no lasting effect and that threshold is quite high. (Dogs are chosen because they live much longer than mice and a good fraction of a human lifetime.)
What limits of exposure would you then recommend?
It depends on whether it's a single dose or spread out over a period of time. If it's spread out it's much better and does even less permanent harm. But even if it's a single dose you can actually safely be exposed to a level one thousand times higher than the current regulations. Looking at the data, an exposure of 1000 millisieverts spread over a year never causes any harm. A separate question is “what is the largest total dose spread over a lifetime that does no harm?” The evidence says that it is 5,000 millisievert but possibly higher. The current ALARA safety level is 1 millisievert per year for the public. In fact the regulation in 1934 was 740 millisieverts per year. The policy of the nuclear industry is counterproductive. They say: “Don’t worry, radiation isn’t going to hurt you,” and then they spend billions of dollars on needless radiation safety. A predictable popular response is: “if it’s so safe, what are you doing all of this for? Are you increasing my utility costs without reason?”
The International Commission on Radiation Protection (ICRP) has walked back some of their stances on radiation exposure in recent years. Yet many of their recommendations still adhere to a linear model of risk per level of exposure. Why is that?
They have reduced their concern about genetic risks but maintained their caution about cancer expressed in terms of LNT. You ask why? There is a large worldwide workforce predicated on ALARA and LNT. Change is very hard for them although it would be simple in principle to have a tolerance at 740 millisieverts per year. The current ALARA recommendation is lower than the average natural background radiation, which is about 3 millisieverts per year.
Where does this fear come from? Why don’t other pollutants, such as coal, cause the same type of concern?
Coal wasn’t introduced to the world through a bomb like Hiroshima and Nagasaki. It’s not good for public opinion to learn about something for the first time with a big scare like that. But in fact, the actual radiation from those bombs killed rather few people relative to those that died from the physical explosive blast and fire (about 1,000 out of 100,000).
Does the public have particular trouble grasping nonlinear phenomena in general? If so, why?
I think few people, even in the nuclear field, understand nonlinearity. The language is not helpful. It’s better to talk about the fact that the body naturally repairs radiation damage, just as the sun doesn’t burn you unless you’re out in it for too long. Even though skin cancer from solar radiation is a much higher risk than nuclear radiation, people still go on summer vacation don’t they? That’s because people have been brought up to think about solar radiation sensibly. They don't talk about non-linearity but the do talk of “not too much on the first day” and “getting used to it”: that is non-linear behaviour expressed in everyday terms. Using mathematically macho terms like linear does not help the public and is unnecessary.
What would a regulatory policy look like, which attempts to incorporate how people perceive radiation risks?
You have to take people into your confidence. For example, in Japan the pictures showing workers in white protective suits with geiger counters is not the right way to communicate with people. They should’ve gone in there with open necked shirts and shaken people firmly by the hand, explaining why everything’s going to be ok. But the trouble was they did not believe that, neither the public nor the officials. If they had studied the evidence, they would have treated the public with more confidence and been believed. But digging up children’s playgrounds in protective gear isn’t only pointless, it's harmful. It scares people. The deaths caused by the unnecessary evacuation are estimated at 1,500 but that is probably an underestimate. The social effects of scaring people about radiation are fatal. Abortions in Greece after Chernobyl increased by 2000, a figure many times higher than the actual radiation deaths from Chernobyl, many hundreds of miles away.
Any change in regulation is going to have to come from a change in the basic common understanding of radiation. Which in turn is going to have to start in schools and with education generally. If one can talk to kids in schools and teach them a little more about the detail of radiation and change their basic understanding, if those kids then go home and talk to their parents, those parents are more likely to listen to them than they are to a politician on the TV. We’ve got to educate people from the bottom up. Many people from my generation will continue to have a phobia of radiation. Of course it’s worst in Germany and Japan, less so in the UK and US, because they have the stronger memories from the Cold War and WWII.
There are times when behavior compounds radiological risks, like smoking cigarettes increases the harm from radon, and poor nutrition in the Soviet Union increased the chance of thyroid cancer. How can regulators consider these effects when setting dose limits?
Radon doesn’t cause cancer. But there is an industry out there that is exploits that belief. If you actually look at the data there is no statistical link. For instance in Cornwall they looked at the occurrence of lung cancer from residential exposure, where the individual radon dose was estimated for several thousand people, but no link was established.
When we make freeways safe we don’t then tell people to sit in the middle of the highway during rushhour. Education teaches people how to handle risk in relation to highways, approaching it carefully and without fear. The same should be true for radiation. It is indeed possible if you look at radiotherapy. There have been a few nasty accidents with radiotherapy (as with highways). So people have to be educated to know what to be careful about. In Japan people are taught about earthquakes and tsunamis in school. As a result 40 minutes after the earthquake when the tsunami came they knew what to do and most people had already moved to higher ground as they had been taught. But five years later people are still panicking about the radiation that hasn’t killed anyone. It’s not a matter of a regulation that says you’re protected because there is no risk at all, but a matter of education, saying you shouldn’t have more than a threshold amount of radiation and being aware of the reason.
What are the larger risks we face when we set radiation limits too low?
In the case of Fukushima and Chernobyl, the larger risks were moving people out of their houses and resettling them when they didn’t have to. You make them refugees. The old people die when you move them. There is social and family trauma when people are told that they have been irradiated if they don’t understand. The danger of climate change is increased when fossil fuels are used instead of nuclear. There is no reason to make nuclear safer than it was at Fukushima. Three Mile Island and Chernobyl were due to human error and safety needed to be improved but Fukushima wasn’t due to any human error and didn’t cause any serious loss of life or adverse effect on the environment. So what can they really improve on (other than moving the location of the generators in that single instance)? The only reason that nuclear is treated differently is because it’s more powerful, and seems harder to understand, which is irrelevant. The human body has learned to live with radiation, much better than it has learned to live with fire or biological waste – both are dangerous and cause fatalities everyday. Yet look at how we treat nuclear plants compared to natural gas plants? No one has died from nuclear waste.
You wrote a new epilogue to your book after Fukushima. What did the accident show?
Three things happened at Fukushima. First, there was a natural disaster that caused a very high loss of life (over 20,000 people). The second was that three reactors were destroyed, the radiation from which affected no one's health at all. The third thing that happened was a panic, which was not a physical phenomenon, but a socio-psychological one. That third event spread around the world and has people behaving irrationally. Immediately after the event nobody knew how much radiation had been leaked so people should have been evacuated, as they were. But two weeks later, the worst was over and some preliminary measurements were available that showed that everybody could have returned home safely. At that time I wrote a piece for the BBC which spelled out what happened and we haven’t learn much that affected any risk to health since. Indeed, if people were taught about radiation and there was another Fukushima event tomorrow, it ought not to be seen as an event of global significance.