Views on Nukes are Off Base

GELFAND ON NUCLEAR POWER-I think that people's attitudes towards nuclear power are predicated on a few assumptions, not all of which are valid. They include one's attitude toward technology as a whole, but this is, by now, a cliche. I would suggest that the more telling attitude is based on the fear of radiation exposure. We ought to consider that fear, and we need to place it in the proper perspective. 

I should warn you that this is rather a long form essay, but there are several topics, so feel free to skip around. 

 

Let's start with the initial proposal. We hear the word radioactivity and if we are normal, we feel fear. Those of us who grew up in the historical shadow of Nagasaki feel it particularly strongly. We imagine gamma rays penetrating our skulls, and beta radiation attacking our tissues. 

This is both a true and a false point of view. It's true in the narrow sense that when humans released highly radioactive material into the atmosphere (such as we used to do with above ground bomb testing), people got a dose. Radiologists in America noticed that the overall background increased after the Russians did a test. 

But that's just a part -- and a small one at that -- of the total radiation we absorb through natural processes over the course of a lifetime. There are three sources you should know about. The first is called cosmic radiation, and is simply the result of charged particles emitted from the sun which move outwards in the solar system, eventually to collide with other atoms in earth's atmosphere. As a result of this wholly natural event, we get a substantial dose of hard radiation. It counts for a significant amount of the total. 

Then there is potassium. We need potassium to live. It's an essential part of cellular life. But it's also a bit radioactive. That is to say, there is a naturally occurring isotope that is radioactive. Every second you are alive, the potassium in your body results in 5000 radioactive decay events. About 90 percent of those events put out energetic beta particles. The other 10 percent put out gamma rays. By the time you finish reading this paragraph, your system will have absorbed a couple hundred thousand such radioactive events. 

You also get a little radiation from carbon, which is the most prevalent atom in your body other than hydrogen. 

You get a little radiation from getting a chest xray and from breathing the air pollution from a coal fired power plant. That's because coal has some naturally occurring  radioactive stuff in it. 

So why don't we all drop dead from all this radiation, and do so early in life? It's a good question, and one that ought to be asked of our anti-nuclear activists. There is an answer that appears increasingly likely, but first we ought to mention Denver and the Black Forest. You see, there are places that have a lot higher naturally occurring radiation than the rest of the world. Just living at a high altitude adds to the load, because the atmosphere absorbs some of those cosmic rays. Then there are places that have a lot of rock, the kind that has a lot of radioactives in it. The people of Denver get both effects. 

People build houses and office buildings out of radioactive stone in Germany, and they get exposed to higher doses chronically. Yet they don't seem to show higher rates of illness or cancer. I must confess that I found this confusing when I first heard it, because back then, we associated any radiation at all with all kinds of horrible things. We were not entirely wrong, as the Hiroshima story made clear, but it is also a matter of dose. Humans seem to have an amazing tolerance for the radiation that comes from our own potassium stores and bombards us from the sky. 

There's also radon gas, which percolates up from under the earth's surface. It's responsible for a substantial fraction of naturally occurring radiation impinging on  humans. It turns out that radon gas combined with tobacco smoking adds substantial lung cancer risk. For non-smokers, not so much. 

In other words, we are all of us, each and every one, pin cushions for radioactive particles that come at us from the sky, from under the ground, and from inside of us. How then do we survive? 

Here's where I'm going to do a little speculating about how non-biologists view radiation and DNA damage and cancer. The prevailing view seems to be that DNA sits in the cell rather passively, that every once in a while a ray passes through a cell, and it may collide with and damage a particular spot in the DNA. Then, as a few of these damaged spots accumulate, it's cancer. There are technical terms for these ideas, one being the Linear No Threshold model and another being the multi-hit hypothesis. What they say is that damage builds up steadily until there is enough of it to cause a cell to become cancerous, and then  you've had it. 

To repeat, how then do we survive? 

It's a fascinating question. If DNA is the most important chemical in terms of long term damage, then we should ask about the known effects of radiation on DNA. It turns out that our cells make something like 200 different genes that are involved in DNA repair. That's pretty close to one percent of all human genes. Some are better known, such as the infamous BRCA1. But recent biology has shown that there are multiple proteins working in multiple systems to repair different kinds of damage to DNA. There are systems that check for DNA damage prior to cell division, and if the cell does not pass this scrutiny, these systems cause the cell to self destruct by the method known as apoptosis. 

Again this is speculative on my part, but I have to imagine that people who are staunchly anti-nuclear to the extent of actively joining the cause, are convinced that one gamma ray might be all that it takes, and we have to do our best to minimize the chance of catching that bullet. 

If you look at modern biology, or even the Wikipedia articles on DNA repair systems, you will begin to understand that the simple model is not really adequate. The simple model postulates that radiation increases the risk of cancer in proportion to dose, and that even a little radiation carries this risk. The proponents of this view even explain it directly and unashamedly. They explain that if 500 units is enough to cause cancer in one person, then 500 people receiving one unit apiece will result (on the average), in one extra case of cancer. 

This underlying idea, central to so much anti-nuclear fervor, is most likely wrong. Think of it like this: A cell gets a few hits of cosmic radiation and is able to repair them. This goes on over time and over multiple generations of cells. But imagine a heavy dose of radiation that clobbers a cell over a short period of time, so that the radiation not only damages genes that can result in cancer, but also damages the DNA repair systems that would have fixed the problem. That is a more likely description of cancer induction. 

I've way oversimplified cell biology here in order to leave out a lot of jargon like microRNA, anti-oncogenes, and the like, but the argument comes down to making a realistic assessment of what a little extra radiation does to the human, and then putting it in the context of climate events that will seriously impinge on human life all over the world. 

And the rational argument over risk, placed in this perspective, doesn't really involve the existence of a nuclear power plant on your local beach. If you look at published figures, nuclear power plants actually put out less radiation than a comparable coal fired power plant. That's because the nuclear plant is specifically designed to contain radioactivity, whereas the coal fired plant is designed to emit it into the air. Coal contains other things besides carbon, and some of these things are radioactive elements that just happen to be in the coal when it gets mined. And all that radioactive stuff goes up the chimney along with thousands of tons of carbon dioxide. And you breathe it. 

Even then, it probably doesn't harm you much, because you have cellular defenses against a little radioactivity. But a normally running nuclear plant is a lot cleaner than that coal fired plant when it comes to irradiating the public. And it doesn't belch out thousands of tons of carbon dioxide every day. And this doesn't even begin to consider the effects of all that other stuff that goes up the chimney of a coal-fired power plant. 

We have evolved lots of defenses against DNA damage because we evolved in the presence of lots of radiation, oxidative damage, and toxic chemicals that we absorb from plants and meat. 

In these two essays, I have suggested that we should evaluate risks such as nuclear power in the proper perspective. When I use a term like "the proper perspective," I mean that our natural fear of being punctured by microscopic particles and gamma rays, real though it may be, has to be considered in light of the almost certain global disaster that global warming will bring if we don't take serious steps to counteract it. We can then evaluate the not unreal risks of using nuclear power vs the very real risks of doing nothing about carbon dioxide buildup. 

A few days ago, I wrote a piece that argued that global warming is not only real, but is a direct and serious threat. I referred to a group of scientists who have called publicly for the increased use of nuclear power as a necessary remedy. Not unexpectedly, I got a certain amount of feedback, both negative and positive. I will consider one particularly pithy response in a later piece, but let's first take up the crux of the argument. 

Back when I was in elementary school, my science textbook listed carbon dioxide as being present in our air at about 280 parts per million. Driving home this first week of November, 2013, I heard on the radio that the level is now at 393 parts per million. That's what we breathe, and if this kind of increase doesn't scare you, then you're not paying proper attention. Within the lifetimes of people we know, the concentration of carbon dioxide has gone up more than 40 percent. That's what you are breathing as you read this, right now. And it will likely continue at least at this level, or near this level, for the rest of your life. 

The consequences of allowing this increase to continue are so dire as to be downright depressing. Just consider, for example, the existence of European civilization. Europe's climate is actually a little warmer than what it ought to be. In European terms, Italy is considered warm and sunny, but if you look at a world globe, you will find that Italy is actually at a latitude that corresponds to the northern United States. Los Angeles, by comparison, is at the same latitude as Casablanca. The other parts of Europe are equivalent in latitude to northern Canada. 

Yet Europe has a relatively mild climate. What keeps it that way? The warm waters of the Gulf Stream make their way into the Atlantic, becoming the North Atlantic Drift, and provide that little bit of extra heating that makes France and England endurable. And what allows that current to keep going? It turns out that cold water from the north recirculates, completing the circuit, allowing the North Atlantic Drift to continue, and saving Europe from being like Siberia. Global warming could interrupt this system. 

In other words, a continued increase in global warming could shut down the Atlantic circulation badly enough to return Europe to ice age conditions. It seems a bit paradoxical that an overall increase in global temperatures could result in a European ice age, but some things are complicated. 

In the meanwhile, rising seas would inundate low lying areas, even as climate changes would cause widespread extinctions due to the changes in habitats. Humans in our temperate zones would find that tropical parasites are encroaching on our living space, and we are not well adapted, either as people or as a civilization, to dealing with them. 

But limiting the argument just to human misery should not be acceptable. With increasing average temperatures, we will see more radical climate changes that may affect a region or an entire continent. And with those changes will come habitat changes that will make life no longer possible for many species. Their lives will become more and more unendurable until they no longer exist at all. 

Global warming denialists argue, in essence, that we can't do anything about it anyway, and maybe we'll get lucky. I don't think these are good arguments. We need as much luck as we can get, but by itself, luck isn't going to be enough. 

And that's where the argument over nuclear power comes in, because it's a matter of perspective. You have to think about the near certainty of global disaster if we don't engage in serious efforts to curb global warming, and take that as your perspective if you intend to argue about human energy use and the technologies we bring to bear to generate power. 

Nuclear power viewed in perspective 

So I'm willing to agree to some extent with the critics of nuclear power. It's fairly expensive to build plants and they don't last forever. There is a certain risk that a worst case scenario will occur, and that a certain amount of radioactive material will escape. We actually have two examples of what were pretty close to worst case scenarios, one in the old Soviet Union and the other in Harrisburg, Pennsylvania. Chernobyl and Three Mile Island are the two examples of what could happen when older technologies meet unforeseen events or bad management. More recently, we have seen the ultimate event, in which a massive earthquake followed by a tidal wave smashed the Fukushima reactors, leading to radioactive leakages and to the loss of the plants themselves. 

I've been to the site of the Three Mile Island meltdown, and as a worst case scenario, it's really not all that bad. It's undoubtedly true that some radioactive gas escaped during the first days of the event. Overall, the result was a substantial economic loss. 

Chernobyl was a lot worse -- it's a dramatic example of how bad we humans can mess things up when we really try. Western technology has required a solid containment structure around a nuclear reactor core since the beginning. The Russians didn't bother, presumably due to the cost. They also used a design that was capable of catching fire and burning intensely for a long time. The result was widespread radioactive contamination, the loss of life among humans and animals alike, and increases in various kinds of cancer, particularly of the thyroid. 

Fukushima takes over for Three Mile Island in terms of a worst case scenario of a western style reactor. It should be remembered that the earthquake and tidal wave resulted in more than 18,000 deaths. The reactor accident itself was, by comparison, microscopic in terms of direct loss of life. One of the most respected of anti-nuclear activists in the United States has estimated a lifetime death toll due to radiation escape as being something on the order of one or two hundred. I think there is a very good argument to be made that this is a vast overestimate, but even if we take it as a given, it pales in comparison to the worldwide death toll, loss in quality of life, and pain, both human and animal, that will be the result if global warming is allowed to go unchecked. 

If Chernobyl or Fukushima were our only available designs, then there would be a pretty good argument that we should find an alternative to the nuclear route. But they aren't. We have designs that stood up even to the worst case scenario of a core meltdown and didn't result in anything like the Chernobyl effect. Harrisburg is still the state capital of Pennsylvania, and it's doing fine. Japan survived Fukushima and will eventually recover. 

I've tried to describe nuclear power and its uneven history as conservatively as the facts require. Now let's consider these in perspective. 

In each of these worst case scenarios, the damage and loss of life has been confined to a rather narrow part of the globe. Chernobyl resulted in the most widespread destruction. The immediate area around the reactor was rendered extremely dangerous, and fallout from the reactor fire was detected widely in Europe. Then it stopped. It is a limited kind of damage overall. Paris and London still endure as livable cities, Munich and Berlin thrive, and Moscow remains. Their populations have not been forced to begin a long migration due to ice age conditions, drought, or increasingly violent storms. The wildlife and insects of the European mainland continue to live. 

Harrisburg was barely scratched by the TMI event. Well over a hundred thousand people evacuated the immediate area for a few weeks, and then they came back. Fukushima is going to continue to be a problem, but a lot of that involves the aftermath of the tidal wave and earthquake. 

In other words, we could survive nuclear power even in its current level of technology. But that isn't the question. There is little likelihood that we will build another generation using older designs. The main issues with TMI and Fukushima had to do with keeping the reactor core cooled down. There are fixes for the problems that occurred at each of these plants, but the world has gone on. What we need now, and in fact already exists, is a redesign that includes passive safety, which is a buzz word for a system that automatically solves its own problems without the need for human intervention. Modern systems are designed so that they don't need to have diesel generators and pumps working in the event of a core problem. The system shuts itself down automatically. 

The argument ought to be over the next generation of nuclear reactors, not the last. We also ought to debate rationally. After all, these are only mechanical devices we are discussing. They are not an argument over the existence of God or about which denomination goes to Heaven and which goes to Hell. It's just steel and concrete, valves and diluted uranium. We should be able to talk about these things at a rational level rather than in tones appropriate to the religious wars of the sixteenth century. We should be talking about the next generation of nuclear power plants and we should be actively engaged in research for an even safer, more efficient generation to come later. 

The human race can build a lot of the new reactors, and they can replace a lot of the coal burning plants that are ruining the earth's atmosphere. They can also fuel new breeds of electric cars and trucks. And once built, they will do so with minimal carbon dioxide emissions. 

There is an alternative proposal by a Stanford professor which involves foregoing any additional nuclear power, but requires the construction and installation of vast numbers of smaller, renewable energy systems. It is a proposal worth considering, but in a later discussion. 

The deeper argument goes something like this: Can we get by with a massive conversion of the world's power sources to solar, hydroelectric, wind, and geothermal? If we could, would we? Or will it take everything we've got, including nuclear, the renewables, and substantially increased conservation to save the world? Most importantly, will humans develop the political will to make the necessary changes in time?

 

(Bob Gelfand writes on culture and politics for CityWatch. He can be reached at amrep535@sbcglobal.net

-cw

 

 

 

 

 

 

 

CityWatch

Vol 11 Issue 90

Pub: Nov 8, 2013