The Manhattan Project

Jay Shelton's Interview

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Jay Shelton's Interview

Jay Shelton is an American physicist and science and math teacher. In this interview, he recalls his experiences from nearly three decades as a high school teacher in Northern New Mexico. He provides an overview of how radiation works and how alpha, beta, and gamma rays differ. Shelton explains the health risks associated with radiation and stresses the importance of quantitative analyses of risks from certain radiation sources. He argues that the general public often overplays many of these risks. He also goes over changes in public perception towards radiation. For example, he points out that radiation was believed to have health benefits prior to the 1930s. Throughout the interview, Shelton describes how a variety of scientific instruments work, including Geiger counters and oscilloscopes, and expounds on the importance of a hands-on approach in science education. He also discusses his personal collection of scientific artifacts, including Revigators and other nuclear-related objects.
Manhattan Project Location(s): 
Date of Interview: 
02/04/2017
Location of the Interview: 
Sante Fe
Transcript: 

Kelly: I’m Cindy Kelly, Atomic Heritage Foundation, here in Santa Fe, New Mexico. It is Saturday, February 4, 2017. I have with me Jay Shelton. My first question is to please say your name, full name, and spell it.

Shelton: Jay Shelton, J-A-Y S-H-E-L-T-O-N.

Kelly: Perfect. Now, Jay, why don’t you just tell a little bit about yourself and what you have been doing for the last umpteen years?

Shelton: I have always been interested in science. I have always been interested in teaching, from the very beginning of my life. I went to college with an eye towards probably becoming a teacher. I majored in chemistry and physics, because I thought that was broad. I am interested in the physical sciences more than life sciences. 

I went to graduate school, got a Ph.D. in physics, and then got a teaching job. I was a professor of physics at Williams College for six years. I got interested in woodstoves and fireplaces, and then for the next twelve or fifteen years, I owned and operated Woodstove and Fireplace Testing and Research Laboratory, part of it in the East, part of it here. 

Then I wanted to get back to teaching. So for then the next twenty-five years or so, I have been a high school math and science teacher, mostly physics and chemistry and calculus, but a little bit of everything. 

Kelly: Terrific. As I was explaining, we are doing a program on Los Alamos innovations, the innovations of the Manhattan Project. It is a very broad topic. Why don’t you begin with one of your favorite angles on this, or talk about the Manhattan Project and why it has been seen as a crucible of innovation? 

Shelton: My perspective maybe is a little different. I have been a high school science teacher in New Mexico, and I am very interested in content which is clearly relevant to the kids. The Manhattan Project and disposal of nuclear waste has been really big and really of interest to the kids and their parents. I have focused a lot of my teaching on nuclear issues, because of where I live. 

Kelly: Let’s go back. Pretend that I’m in the ninth grade, sitting in your class. Can you tell me about radiation? Can you tell me what is going on at Los Alamos that I should know about, or how did this all come about? What was the Manhattan Project trying to do?

Shelton: That was a lot of questions.

Kelly: It was. Choose what you would like to answer.

Shelton: In terms of radiation, which was where you started and where I start with my students, because most of the public does not fully understand all the kinds of radiation.  

I have the kids come up with any word that they associate with “radiation” randomly for about fifteen minutes. I put the words on the board in three columns. Then we later talk about why I did that. The distinction is: radiation which is capable of ionizing atoms, radiation which is not, and radiation which can under some circumstances. Then we talk about the health effects, because that’s primarily what the kids are potentially afraid of, or society is.

Non-ionizing radiation can have health effects, but they are pretty modest and hard to measure. Ionizing radiation clearly does have health effects, because it ionizes atoms and molecules, which means it kicks electrons out, which means that it disrupts bonds, because the bonds between atoms to make molecules are all about what the electrons are doing. So it can change the chemistry, it can change the chemicals in your body. Therefore, of course, there’s a potential health impact. 

That’s the primary distinction: whether or not the energy is high enough to knock electrons out and hence change the chemistry. The kinds of radiation, of course, which do that are X-rays and gamma rays and any fast particle with mass

Kelly: What radioactive elements produce gamma rays?

Shelton: Radioactivity can produce gamma radiation and beta and alpha and neutrons. There is a variety of interesting stuff. There are many radioactive atoms that are naturally on earth. There are some radioactive atoms that you can produce with nuclear reactions, as reactors and bombs do. Am I answering your question? 

Kelly: Yeah, sure. However you think would be most edifying to people to better understand what alpha, beta and gamma radiation is about. 

Shelton: Alpha Elephant, Beta Bunny, Gamma Sammy Sidewinder. My kids all look at me when I say that and think, “The guy’s lost his marbles, what is going on?” But I have done a lot of work with groups of teachers—some of it sponsored and helped by Los Alamos, some of it not—to try to develop tools that help people understand. That was a phrase that we came up with. Alpha Elephant, Beta Bunny, Gamma Sammy Sidewinder.

Alpha particles are like elephants, in the sense that they are by far the heaviest of those three if you look at the mass. They also are the slowest. An alpha particle is a nucleus of a helium-4 atom, two protons and two neutrons. That is pretty massive in this context.

Beta radiation is one electron going fast—way, way, way less massive by factors of thousands. They go faster.

Then Gamma Sammy Sidewinder is gamma radiation which has no rest mass, travels at light speed. You can’t go any faster.

That’s a way to help the kids understand or remember some distinctions amongst them all.

Kelly: I have never heard that. That’s excellent.

Shelton: I had a student, who was a very good artist, draw alpha and beta and a gamma and make them look like those three creatures. 

They are very different in what they do, too. Alpha radiation is slow, has a very hard time getting through other atoms, and therefore doesn’t really penetrate our body coming at it from the outside.

Beta is in-between. That’s an electron. It’s a little smaller and it can maybe go a few millimeters into our bodies coming from the outside.

Gamma radiation is very penetrating and can go completely through you. Sometimes it goes complete through you and does nothing to you, because it went through, it didn’t deposit any of its energy. Some of it does get deposited.

They are very different in terms of what they do and what kinds of protective measurements are necessary, if you’ve got stuff in the environment which is emitting that. Alpha radiation coming at you from the outside, no worry. There is alpha radiation and beta and gamma coming from everything. Everything is naturally radioactive.

Alpha is a concern if you eat or breathe the materials which are going to send out that radiation, because then you don’t have a protective layer of dead skin. Beta radiation also is mostly of concern when consumed or breathed. Gamma is a concern anywhere, because it does penetrate.

Kelly: Tell us more.

Shelton: I guess the next issue is, how dangerous are these things? The health concern is primarily cancer. There are other things that ionizing radiation can do, but I think the biggest concern is cancer. It results when any one of these kinds of radiation scrambles the chemistry of DNA in a very particular way, and it doesn’t get repaired, which it usually does. It can lead to cells having the wrong instructions. The cells are now told, “Ooh, I love myself, I am going to make more of me.” That just proceeds and proceeds and proceeds, and you get a tumor.

How much radiation does it take to be a significant risk? I think the only way to address that is by comparison. Here are the two reference points that I think are perhaps most useful. One is since there is natural background radiation everywhere—it’s coming down from the cosmos, it’s coming from our own bodies, which have carbon-14 and potassium-40, totally natural. Other things in us comes from the air, from radon, comes from the ground. So it’s all around us at low levels.

I will back up a moment. One of the ways, if you want to scare somebody, what you do is you tell them that we get hit either internally or externally by ionizing radiation on the order of 10 or 15,000 times every second. That’s the rate at which we are being bombarded. Each one of those has enough energy to perhaps, on average, ionize thousands, tens of thousands of atoms in your body, molecules in your body.

If you add up the total number of busted bombs that we get, it is something on the order of a billion. Depends a lot on details, but roughly speaking, we might get a billion broken chemicals in our body every second of our entire lives. If you don’t get quantitative about that, you just sort of get scared and think, “My God, I must be dead!” Well, we’re not, and so the question is well, why not?

I love to ask students that. Usually, at the ninth grade level, where I have done a lot of teaching, some of them will realize that actually the number of molecules in our body is big. Although a billion is big, maybe it is tiny compared to what is there. That is part of the answer. Part of the answer is a lot of the damage is totally inconsequential. Part of the answer is that a lot of the damage that could be gets repaired. The bottom line is, it is not really that scary.

In order to help people understand how dangerous various kinds of radiation are, various sources, the two points of comparison that I think are most useful are: one is, what is the probability of getting cancer from the daily natural radiation dose that we get? I am not going to give a number for the probability of getting cancer, but there is a certain risk of getting cancer from a daily dose.

The unit that Los Alamos has always used, and it’s one of the few institutions in the world—I don’t know if they still use it—but it’s not the metric system, it’s the rem and the millirem. In terms of millirems, the average dose per person per day in the U.S. is on the order of one millirem. The average dose from one dental or extremity X-ray diagnostic procedure is on the order of one millirem. Apparently, millirem is not too scary. We get it every day naturally, and we get it every time we have a diagnostic procedure. So probably that’s pretty negligible.

In terms of millirems, how many do you need to get in order to have a detectable chance, increased chance of getting cancer? It’s on the order of 10 or 20,000 millirems, gives you roughly a one percentage increased chance of getting cancer sometime in your lifetime. Below that, it’s unmeasurable. There may be an effect, there may not. But it’s on the order of tens of thousands to have a chance.

Now we can look at various things that people are afraid of: radon in your house, getting an extra X-ray. There are some people in Santa Fe that I know who never get X-rays, because they are scared they are going to get cancer. If the X-ray’s a millirem—I guess, here’s another number that we could toss out. The number of millirems we natural get in a lifetime is 20 or 30,000 millirems. Getting one medically useful diagnostic X-ray might be a good balance in terms of healthcare, as opposed to additional risk. The risk is unmeasurable at that level. There are a few medical procedures which can have measurable consequences, and again, in medicine it is always a tradeoff. What’s the benefit of having this procedure?

One of the most interesting experiences we had in our classroom was, a mother of a child who I had in ninth grade, who called up and said, “May I come by your classroom right after I get out of the hospital, and would you check the radiation dose that I am emitting and give me your opinion as to whether or not it is safe for me to go home and hug my children?” Interesting request, and of course, I said yes.

She had had a therapeutic iodine treatment of an overactive thyroid. The half-life of that isotope is a few days, I forget exactly the number. You stay isolated for a while, you live in a motel, and after a while it’s considered okay to go home.

She came in, and I didn’t tell the kids all that was going on. I believe in mysteries and puzzles. They all had Geiger counters. She walks in and they turn them on and everybody’s Geiger counter was going way higher than it used to be without extra sources in the room. I asked them to explore. I told the mother in advance what I wanted to do with this education.

They explored around and they ultimately located that it was she, and she was brave enough to let them find out where in her body most of it was. It was everywhere, but of course, it was more at the thyroid. She was an absolute screamer in terms of Geiger counters making an exciting noise. Normally, you would get one count every two seconds in our background classroom.

It was screaming. Then we talked about, “Okay, now what’s the dose going to be?” The Geiger counter has a little conversion factor for counts per second, two milligrams per hour, whatever. I don’t remember exactly what the numbers were, [but of course, it was negligible and of course, it’s okay to go home and hug your children. She also had her clothing, because you have this radioactive iodine everywhere in your body to some extent. It is in your clothing and whatever.

It was just a very educational experience. Looked scary, but you look at the numbers and hugging a child with some fraction of a millirem, if you hugged them for hours a day, it was negligible.

I am a great believer in being quantitative. You have to be quantitative. If you are just scared of radiation, life is no fun. How much does it take to be a problem? Then you can decide how to react. I think that’s very important for ninth graders, very important for everybody in our society, and very important with every hazard, not just ionizing radiation. Ionizing radiation happens to be one where quantification of health impacts has been very well researched. There are some others where there is less that iss known. It is possible to quantify risk.

I also had a student who still lives in Santa Fe. She is a firefighter and a paramedic. One of her claims to fame was that early on in her high school career, she was a volunteer in a local fire department and they have ways for kids to volunteer in a useful way. She was so anxious to become a real volunteer—not sort of relegated to non-dangerous things—that she actually got, through hard work and lobbying, the state rules on how old you have to be to become a paramedic or a firefighter, she got them changed by a year or two. So she’s famous, in my experience.

There’s a procedure where you inject radioactive atoms. Where you have a bone that is damaged but not cracked enough to show up in an X-ray, there is biochemical activity there and you can inject a compound, which preferentially goes where bone is working on repairing itself. Then you look at the image that you get from radiation coming from the person, and you can see whether there is damage, which X-rays don’t pick up. I’m sorry, I don’t remember the name of the isotope right now.

I said, “Can I come?” So we went down to the hospital here in town. I brought instruments, she knew about the instruments. We asked the technician whether it was okay if I stand there while we do it, and went through the whole procedure of opening up the lead container and pulling off the thing and giving it to her, and then looking how it spreads. Then they do their imaging of her. It is wonderful to have a student who is so unafraid and understanding, because she understands radiation, that it is just totally a non-issue to have the procedure done, and to have your science teacher there to get some data that we can then talk to the class about. It was a lot of fun.

The other thing that I can recall that we did that is more related LANL [Los Alamos National Laboratory] is, we were very involved with, as a school, as a class, and I as a person, with the whole development of whether or not the WIPP [Waste Isolation Pilot Plant] site ought to be there, etc. It was very, very controversial, all kinds of public hearings. I testified. My class and I did all kinds of research on it.

After it opened, we were able as a school, we would have annual field trips. We took the entire ninth grade class down to the WIPP site underground and even when there was waste underground, to where the waste was—until 9/11, and then things sort of got tightened up. We did it once after that, they gave us special permission.

But here is the interesting story. Of course, there are going to be some families, some parents who think that taking children to the WIPP site when waste is there is unreasonably dangerous, and refused to let their children go. As a school, we, of course, would respect that and we would say that’s fine.

What I did—I’m always looking for the most educational value in these things. We had lots of radiation detection instruments. The kids who stayed had instruments. The kids who went had instruments. We took them everywhere, measured everything, enough so that everybody could calculate approximately what their total dose was from radiation from any source during the whole trip.

I knew—and it was so interesting for the kids to discover—that if you went on the trip, you got a much smaller—I shouldn’t say much, but you got a smaller radiation dose, always trivial from background radiation. Understanding why it was smaller when you go to this radioactive waste dump was so interesting.

First of all, Carlsbad is lower in elevation, so there is more air between you and the cosmic radiation and so there is less cosmic background radiation. The soil has less uranium and thorium in it naturally, and therefore, there was less ground radiation, natural background radiation. You benefit from that in any case.

But when you go down into the salt caverns, this is two or three thousand feet thick of salt and the radiation, I mean, the waste is somewhere in the middle. The salt is very clean radiologically. It has very little uranium, much less uranium and potassium, and particularly uranium and thorium, than the soil and dirt does. So the background radiation dose is close to zero.

With our little Geiger counters, which give thirty counts a minute in our classroom in Santa Fe, we got maybe one or two counts a minute. You just turn it on and you listen and you look at it, and nothing happens. Very rarely, you hear a tick. You have all this time that you are at lower elevation, lower uranium background, you have all this time when you are down in the tunnels, a few hours, where you get virtually no background radiation. Then you go up to the waste, and when you get within—they don’t let us get very close to the waste—but we were, I don’t know, 100 feet away. You can see the barrels there, which was very exciting for the kids, and you could see the Geiger counters registering a little bit more. Then you add all that up and, of course, we got less radiation dose than the kids who stayed in Santa Fe.

I think these children, at ninth grade, their minds can be changed. They can have fear of something and lose it. I saw that as one of my jobs: let’s quantify risk. I’m not sure I influenced any parents, although I think I did. I think some of the parents thought, “Oh, they got more radiation dose here?” That sort opens the window to, “Well, now wait a minute, does one atom of plutonium kill you or one zap from alpha?” No! It was really wonderful educationally. We were not able to do it after a while, but it was a lot of fun.

We also did a lot of work around LANL itself in Acid Canyon collecting samples. There have been various degrees of cleanup in areas where waste was dumped very informally in the early days. We always took kids up when there was some new development up there and collected samples and brought them back and made measurements. It was fun, and very educational.

Now, the Waste Isolation Pilot Plant, which abbreviates WIPP, WIPP, is a major national nuclear waste disposal site, which is now active in southern New Mexico, near Carlsbad, in salt deposits. It takes waste from national labs. I guess, it’s all related to military applications, waste from making bombs. It is low-level waste from making bombs. It is not spent fuel from nuclear reactors. It is the floor sweepings and the gloves and the booties and stuff that wasn’t very concentrated, is what goes down there.  

When the proposal was put forth to have that waste be in New Mexico, it, of course, was controversial. If there is one kind of issue which gets me really worked up emotionally, it is when people are trying to make smart decisions, whether it’s technical information or science, and they have the wrong information that they are using to make a judgement. I have no problem with anybody saying, “I don’t want the waste dumped down there,” or whatever, as long as they understand what the risk is.

I spent a lot of my effort with my students and in my testimony trying to quantify—because that’s my thing—you have to quantify how big the risk is. One of the issues, which had people really, really scared, was trucks carrying this radioactive waste, these WIPP trucks traveling through Santa Fe. Initially, they were going to go right down St. Francis Drive, a main road in Santa Fe. Ultimately, money was provided to build a bypass so it went around Santa Fe. Of course, now people are developing all the land around the bypass, because I don’t think that really was the issue.

I am good friends with a lot of the anti-nuclear folks in Santa Fe. Our kids have even volunteered with them on community service programs our school had. But that’s one of the issues that drove me crazy, because we got ahold of various studies that had been done. Of course, these issues are studied endlessly by all kinds of groups before a decision is made. The studies that we tended to focus on were the ones done by a New Mexico group, not DOE [Department of Energy], not LANL, but I think actually an independent group of technically competent scientists that the state of New Mexico hired to say, how dangerous is this?

I’ll give you a few details. They have various degrees of accidents. I guess this is done in any accident study, and they range from zero to ten or something, how bad the accident is. A zero or a one is a bumper-toucher, and a two and a three, and they get more and more violent. At the extreme end, you have the truck exceeding the speed limit, hitting a gasoline truck exceeding the speed limit and a head-on collision, and the WIPP containers come apart and the drums break and there is a fire and so radioactive material is carried up in the air, and therefore, some people breath it. You got to find a way to get it inside people to have it be really hazardous.

There was a newspaper article, which when that study came out, said, “WIPP trucks traveling through Santa Fe will kill two to three people from cancer,” went on and on and on. I got the study, we looked at the study. Now, where does this number come from? And it’s there. What they do for each degree of accident is say, “How many people are likely to die over the next century or two, taking into account the half-life and the extent material lasts in the environment?”

They also give a probability for each kind of accident. The probability for bumper-touchers is moderately high, you know, one percent, five percent or something for the trucks coming through Santa Fe. The probability for the one that has deaths—none of the others did, they were too small to even talk about—was .00000001 percent, I don’t remember the number. So yes, the study did say two to three people would die, but, no, it’s not likely. They came out with the most likely number of fatalities due to the probabilities of all ranges of accidents, and it’s a tiny, tiny fraction of one, negligible compared to every other decision you make in your life. How many people die from other causes in Santa Fe? Huge.

I tried to persuade people that the risk of accidents of trucks coming through Santa Fe was utterly negligible. It was very interesting. I got a lot of flak from other people who were testifying on the other side at the hearing, of course. It was clear that there are people who really do believe that one atom of plutonium will kill you.

My job during all these times to try and say, “No, it is more than one. In fact, you already have, I pointed out, 100,000 or tens of thousands of atoms of plutonium in your body. Everybody does, because it’s been vaporized into the atmosphere and it is everywhere. We get a little bit and does it matter. No. What’s the dose? Utterly negligible, much less than any other decision you make in your life, like taking a vacation in the Rockies or flying to Europe or whatever.

Kelly: Yes.

Shelton: I’m looking for guidance from you for where to go.

Kelly: This is good. Have you looked at the Japanese epidemiological studies, and the death rates or the incidents of excess cancers associated with various levels of exposure? I’m just curious. It sounds like you may not have.

Shelton: I don’t feel like I’m an expert. But yes, I have looked at those some. I have looked quite a bit more at Chernobyl and Fukushima, for the same purpose I always have, and that is, how bad? In terms of the World War II numbers, is that what you’re talking about?

Kelly: Yes. You know, the survivors. They have done all sorts of longevity studies.

Shelton: Yeah. I’m not an expert on that, no.

Kelly: But, you did on Three Mile Island and Chernobyl, the risk associated with them?

Levy:   Fukushima?

Shelton: Well, especially Fukushima, because, again, I try to do things in class that are current.

Kelly: Sure.

Shelton: That was going on when I still had students. I did look at that. But it applies to all these other—especially the reactor accidents, not so much World War II.

The conclusion of all the good studies, the studies that are done by competent people, my understanding is the conclusion is that there is far greater risk to health from all the other things that are going on that are not radiological. The fear of the radiological health causes evacuations, and the evacuations can be kind of panicky. Enormous psychological stress. I don’t know what all the issues are. People are afraid to eat. I suppose they do eat. But there are all these ancillary things, which have measurable consequences. Suicide rates, I think, in some cases are measurable.

In Chernobyl’s case, people have done some awful things, thinking that they had to do it to protect themselves. It’s due to all that misinformation about the dangers of radiation that is the biggest health risk in terms of consequences for those ones, including Japan.

Now, the one thing that I do like is that apparently—perhaps related to Fukushima, but maybe it was going on already—that I think that the internationally recommended radiation dose levels at which you don’t need to evacuate or you can bring people back in, have gone way up compared to ten years ago, and very logically.

It used to be that people were being so conservative that they would keep people out for no reason at all. Now there is some local discretion, and it gets down to this level. That’s the one place where I have seen a little bit of sensible quantification come into some of these issues. But it is the fear that causes the damage, more than the radiation. Too bad, really is. It is tragic, unnecessary.

Oh, and the fish. I had all kinds of people, including my son, who lives on the West Coast, “Oh, is it safe to eat the fish? Because I read an article that you can detect strontium-90 or something in the fish. It came from the reactor accident in Japan. Can I eat the fish?”

There have been some wonderful, good, quantitative analyses of the fish and the radiation. Of course, because science is so good these days, you can find one atom almost of an element. Sure, yeah, there is strontium-90 in there, but what else is in there? I don’t remember all the comparisons, but of course, the dose from the atoms that came from the reactor is way smaller than all the other doses that are natural that are in fish.

You got to be quantitative to understand whether or not to be worried. If you are quantitative, then you can stop worrying and having all those bad psychological impacts about things that don’t have any impact. You could worry about things that do matter, not things that don’t. That helps you and it helps the world.

Another thing I did, and shared with my students, was to look at the standards. Every time there’s a news report, I try to get down to the bottom of it. One of them was, “Oh, the spinach has been, or the lettuce or something is now unsafe to eat in some of the areas near the reactor.”

I looked up what those standards are, what is the dose that you would get if you did eat it, and what are the assumptions that it’s dangerous to eat it. Everything is fascinatingly conservative. The assumptions are—I remember a few of them—are that we’re going to declare it dangerous if—now, I don’t know what the dose is that you would get, but it’s a few millirems or a hundred millirems or something which has an unmeasurable effect, that’s sort of the threshold. Maybe a hundred, I don’t know.

But they also assume that that food is the only food you eat, whatever the contaminants are. I am only going to eat lettuce for the next year, and that you are going to eat it for a year, and at the same level of contamination. Then we’re going to calculate the dose to you. There are some other conservative things in there. When you find out how the standards are set, well, no, I’m not going to worry about the fish, I’m not going to worry about the lettuce, because the assumptions are so conservative, but by many, many orders of magnitude. That’s interesting, and it’s quantitative. It was really fun sharing that with my ninth graders. “Oh, well, maybe it’s not so bad.”

Here is an interesting little factor to do with measuring radiation. One of the things that teachers are fond of telling everybody, the public and their students, is that everything is radioactive, including you and me. Then when you sleep next to somebody, the gamma rays from your potassium-40, entirely natural, zap to your partner or whatever.

We talked about that quite a bit and tried to measure. It’s hard to measure, and it’s hard to measure because the background radiation environment that we live in is so strong. Over all the years I was teaching, we found two environments where you can actually measure the radioactivity coming off of a normal adult healthy body or a kid.

One was at the WIPP site. When you go underground, the background radiation is so low that if you hold a very sensitive detector out up by itself in the mines and get a reading, and then you get all the ninth graders to come around and squeeze and get as close as they can so you got all these bodies around it, we had a very slight measurable uptick in the radiation dose.

The other environment where we found it works is in water, in a swimming pool. I didn’t have a chance to do this with my kids as much as I would like to. But again, if you have an underwater-capable detector and you put it there without a body near it, and then just one person comes up and touch it, you get a very substantial increase in radiation.

The problem is the background radiation is so high. So in reality, if you hug somebody you both get a smaller dose, because each of you is blocking background radiation dose more than you are contributing your own shine. It takes a very rare environment—in a submarine or underwater or in a salt mine—in order to have being close to somebody result in an increase in net dose. That was fun.

How a Geiger counter works—I should have brought one. A Geiger counter has inside of it a Geiger tube, and a Geiger counter only detects ionizing radiation. My students would often ask, “What happens if I put it in a microwave oven?” Well, if you put a Geiger counter in a microwave oven you will kill it, because the electronics will get fried due to all kinds of other circumstances. But it only detects ionizing radiation. You may recall or you may know that ionizing radiation knocks electrons off of atoms and molecules that it happens to encounter. The detector has to be sensitive to that.

Inside of every Geiger counter, there is one or more Geiger tubes. The ones in the little Geiger counters that most people have are not very big. They are about that long, and maybe a centimeter or two thick. The tube has a wire going down the middle and a metal can around the outside and kind of a special mixture of gases, but that’s not critical.

Ionizing radiation comes along. It has to get through the metal, which means no alpha radiation will get in, but it’s good for beta and especially for gamma. The ionizing radiation comes through and it will ionize some of the gas that’s in there.

Now, I left out a really important thing. There is a huge voltage difference between the wire and the can, which means if there’s any charge in the air, the electrons get pulled out of the wire and the positive ions get pushed out to the can. It is a very, very strong electric field. If you create a bunch of free electrons, which is what ionizing radiation does, it knocks them out. The electron gets pulled very strongly towards the central wire. The electronics are not usually sensitive enough to detect a single electron.

Now, of course, that ionizing radiation may ionize a few atoms, but here’s the real key. You get amplification, and you get a cascade. You get one electron, which is now lose from its atom, can start moving very fast towards the wire. It get going so fast that it itself becomes ionizing radiation, and when it bumps into another air molecule, it will knock an electron or two off of it. Now you have two. They now will get accelerated and they bump into another and you get more and more. You get a cascade of electrons being created by the process, and even though it’s still a very small number of electrons, you can afford the electronics that can detect that pulse of electrons hitting the wire. That makes a tick if the electrons do that, makes a light blink, makes a counter go up by one. It directly is detecting ions that are created by ionizing radiation, which of course is what we need.

Oscilloscopes are awesome instruments. One of their claims to fame is that they can measure things that are happening very, very quickly in time. If you have a meter with a little needle on it, and the needle has to go back and forth, it’s got mass, it’s got inertia, and it takes a little while for it to respond and your eye can’t catch it. An oscilloscope is a way to measure something where it is electrons only which are moving. They are so lightweight that they can go up and down and whatever you want them to do very, very quickly, which allows you to see things that are happening over very, very short time periods.

An oscilloscope has an electron gun, and it has a screen. You look at the screen and you can see glowing light up there, lines, whatever the system does. But the key is, you have an electron gun, you have a vacuum between the gun and the screen. The screen is coated with a material which will glow when the electrons hit it. That is how you are going to see where the beam of electrons is hitting. You have to have a way to have the beam get very narrow, not a big spray, and there are ways of doing that.

The way you make an electron gun is, you just warm up a wire so it’s red-hot. Anything that’s red-hot has enough energy that it’s just throwing off electrons, so any wire red-hot and you keep refeeding electrons from a battery or from the power grid or whatever. You have electrons being spewed off, and you get a beam that’s going pretty fast towards the screen. As it goes towards the screen, it passes between plates of metal, which may be connected to the thing you are trying to measure.

If this light gets to be a little negative and this one a little bit positive, and you have a negative electron in here, it’s going to get pushed down by the negative plate and pulled down by the positive plate, and so it will get deflected a little bit. You don’t want it to get pulled and have a collision, you just want the beam direction to change a tad. You can steer it up and down by the charge on these two plates, which can be connected to an experiment. Typically, that’s true.

You have another pair of plates that are oriented like this, and typically, it’s sort of a time base. They are automatically and electronically charged positive and negative in a gradual way to make the beam go across the screen. Then if something’s happening, it will go up when this one does something.

It’s a graph of what’s happening in your experiment as a function of time. Because it’s only electrons that go up and down and go this way, you can measure things that occur in a nanosecond. You can measure things—I don’t know if that was true during the Manhattan Project—but it is the tool for looking at things that are occurring quickly.

Let’s see, the energy in anything that’s fissioning, whether it be a bomb or a nuclear reactor or just a decay—let’s talk about uranium, since that’s one of the common ways of doing it.

The energy comes from the nucleus, and it comes because in a fission process, the nucleus fissions, which means it comes apart. Interestingly, the energy is not nuclear, it is electric. When the nucleus comes apart and gets just a tiny bit distant from the way it was packed together, both halves, both pieces—they aren’t equal halves—both pieces are highly charged electrically, because the nucleus of an atom contains protons and neutrons. Protons are positively charged, and they are really close to each other in a nucleus. The neutrons are neutral.

The existence of the protons means the nucleus is being pushed really hard apart, but there is a strong nuclear force, which keeps it together as long as everything is close together. As soon as you get a tiny bit of separation, you have this fierce repulsion due to the like charges, positive and positive, and that’s where almost all the energy comes from. It’s released in a nuclear bomb. It’s electric energy, it really is electric energy triggered by a nuclear process, kind of.

The whole atom consists of a nucleus and a bunch of electrons going around. I think a very useful model for any atom is that if you were to blow it up, make a scale model of it the size of a soccer field or a football field, and keep everything in scale, the nucleus is in the middle, fifty-yard line. If you walk out there, you can see it. You can’t see it from the outside, because it’s on the order of a centimeter in the middle of the field.

The electrons, you can’t see, because they are too small even when the atom is magnified that much. In fact, electrons are so small that even today nobody knows how small they are. People do experiments shooting electrons at each other and trying to get a bump, something other than just a gradual push. Can’t do it, despite all the accelerators. The electrons are invisible. There’s this little lump in the middle, and that’s what all atoms look like when magnified that much.

That’s relevant for how you get a chain reaction, a fission reaction going. The energy comes from these two pieces being pushed apart. How do you get them to fall apart? There’s a spontaneous fission rate, which is very, very small. It’s kind of like radioactive decay, doesn’t do you any good, because it’s too unlikely. You have to encourage it. Of course, you want in a bomb and a reactor to get the fissioning to occur on your demand, not just randomly waiting.

It turns out that if you send a neutron—which is one of the particles that’s already there in a nucleus, neutrons and protons—but if you send a neutron and it hits a nucleus, it has to be a pretty direct hit. That will often, with some nuclei like the ones that are used in reactors and bombs, cause this fissioning to occur. Well, that’s nice, you get a whole bunch of energy, but you need more than one.

The way that most people have designed reactors and certainly bombs, it takes advantage of the fact that when you do get a fission, not only do you get these two big parts that push away on each other, but you get a few neutrons to boot. Between two and three neutrons come out as well. Since it took a neutron to make this guy fission, maybe we can use those neutrons to make another guy fission, and we can get a whole bunch of them to go.

That is really hard, and here’s why. That model of the atom, almost all empty space. I mean, really, you stand and look at it and you can’t even see the nucleus when you’re at the goalpost, and that’s an atom. It’s almost nothing. If you get one atom to fission and you get two or three neutrons to come out, they go out in straight lines in random directions. You can’t control where they go.

Suppose we had a few other atoms around this one, like a pile of six or eight football field sized things around there. Two or three neutrons come off and they go in a straight line. What are the odds that you’re going to hit a nucleus of one of those other atoms that’s around you? It’s nil, because they are so small, and you are going in random directions.

The folks at LANL had to figure out how many atoms you need and what geometry to get, and to make it probable that two or more, that more than one anyway, of each of those new neutrons that are created are going to stimulate another fission, because you want to get a whole bunch of them to occur at one time. That’s where you come up with masses that are about this big, as I understand it, for fissional material—for uranium or plutonium, it’s a little different—in order to have a reasonable chance that you are going to be able to use the neutrons that come from some fissions to create new so you get a chain reaction.

I did bring but I don’t think I will use it, but a really nice example of a chain reaction is to light one end of a book of matches. If you light it over here, this one is going to burn, too. What fire needs in order to spread is you have to get it hot enough to ignite it, to make it go. When this one goes, it does get hot enough to heat up this one, it gets hot enough to heat up that one, and it spreads. In the case of a nuclear reaction, it’s not the heat, not the temperature, but it is the neutrons which spread and bump into another one.

It is extremely hard. The probability is so low of hitting another atom that you just have a whole bunch of them. It doesn’t do to spread them out in a sheet or anything else, because then most of them are going to miss. You need to make it as compact a shape as you can, which is a circle. That’s what they figured out and did.

Kelly: Maybe you can now talk about aspects of the design of the bomb?

Shelton: Okay. There are some other problems. You need to have a big-enough mass, which is maybe grapefruit-sized or whatever. Then if you can get a fission to start, maybe you will get a bomb. Well, the answer is you don’t. You can build that and you can get a fission to start, and you will get a bunch of others of them to fission.

But these reactions release so much energy so quickly that if you were able to suddenly create a critical mass, which is what this is called, it would disassemble itself before a significant number of the atoms had fissioned. The reason is that the atoms, the mass, whatever, gets so hot so fast that the pressure builds up so much from the vapor that it just pushes uranium or the plutonium apart. You get a mess, but you don’t get a big bang. You have to somehow try to keep it there, despite the fact that it is getting unbelievably hot for as long as you can, so that more of the atoms will have a chance to fission so the total energy release is big enough to make a big bomb.

As I understand it, they worked on two ways of doing that. The simpler way was to have two pieces of uranium that were not right next to each other, because you don’t want this reaction to start. Then you try to bring them together in a way which will hold them together for as long as you can. The design was to have a gun. I guess they had a core at one end and a hollow piece at the other end, both made out of enriched uranium.

You set off an ordinary explosive down here to shoot one piece as fast as you possibly can down the tube, and it will slip over the cylinder at the other end. Pretty soon it gets critical and things start happening, but because of the inertia of bringing this slug in, that it will be around for enough time to get some small fraction of the atoms to fission so that you get a bomb. The efficiency, as I understand, was pretty low. Almost all the atoms got vaporized, and the energy was not released. But it worked. So it was using inertia, I guess, really, to hold them together long enough to have those neutrons find other atoms, for all the atoms to get vaporized and just go away.

The other design, which I think was the one that Los Alamos really struggled at and weren’t even sure they could achieve it—this gun thing they thought would probably work, not very efficient—involved taking plutonium, I think, is what they used, and compressing it. Again, I guess it is inertial in the same sense. But instead of having a hollow target or a solid target and a hollow tube and bringing them together, you try to compress everything spherically, symmetrically, to bring the critical mass together.

That is a really hard engineering problem. The energy released is so fierce in here. If you don’t have equal pressure coming in from all sides and every square millimeter of all sides, if there is one place where the pressure is a little bit less when you are trying to squeeze this thing, then all the material is going to squeak out the little hole.

Conventional explosives were used to compress this stuff, just like conventional explosives were used to shoot in this gun design. But the task of having uniform pressure from a spherical explosive, I understand, was really hard. I think it took years just to see if they could do that. Part of it, of course, is timing. You have to have each part of the explosive go off at the same time, but it’s also the manufacturing of the explosive. It has to be unrealistically uniform. You can’t have .01% higher explosive power here than here, because then it is going to squirt out over here before it is held in long enough to get enough reaction to be worthwhile. Hard engineering.

Kelly: That’s great. That gives you a real good sense of why this was challenging.

Shelton: Yeah.

Kelly: One thing you might talk about is the state of electronics. For example, you say you need these detonations that were at exactly the same millisecond.

Shelton: Yeah. I know a little about that. When you would set off this huge distributed explosive and you need all parts of it to go at the same time, you have to worry about everything. You have to worry about the time that it takes electrical signals—there are a bunch of detonators that are involved, I presume—I am not really an expert—but you have a whole bunch of electrical signals that are coming to set it off. They have to arrive at exactly the same time.

Of course, you worry about the length of cable. Electrical signals go through conductors at light speed, or 20% of light speed. It’s very, very fast. If you have an extra foot of cable going to this igniter compared to that one, it costs you a nanosecond. I think that’s probably a killer. You can’t do that.

Then when you want a little spark to go off, either to initiate those signals—I don’t know what was happening down here in the explosive—but anytime you want to initiate something, if you want it to happen reliably—I know a little about this, because I have collected some of these things. There are a lot of electronic tubes that had radioactive material in them. It was a spark gap, then there are two places with a little gap in between, and a spark is going to go across. It is going to go across on command or something else in the circuit, and you don’t want any hesitation or delay.

You coat one of these or both of these electrodes with radioactive material to ionize the air between these two things, so that when you get a big surge of electrons that needs to jump across that gap, they won’t have to wait unreliably for the lightning stroke or the spark or whatever to get things started. It is continuously there.

This idea was, I think, sort of fraudulently used in spark plugs in the late ‘40s and ‘50s. People thought, “Oh, we want the spark plugs in our cars and trucks to go off reliably,” so you could buy polonium-coated spark plugs. I think it was mostly a sales gimmick, but there’s a real principle there. You want ionized air around gaps where you want a reliable transmission of a signal.

Kelly: They were very clever, indeed.

Shelton: Ever since I came to New Mexico, which was like thirty-five years ago, but particularly when I started teaching, which was twenty-five years ago, as a teacher, I am probably the craziest teacher that I have ever known about having stuff, things to demonstrate and show. I never go to any class, including math classes, and it can be completely irrelevant. I try to make it relevant. But if you don’t have the interest of your audience, you don’t get anywhere.

It was a real natural that I started collecting nuclear stuff. The theme of my collection has always been things that illustrate changing public attitudes towards radiation and radioactivity. There has been a complete swing, starting in 1895 or so, up until 1930. Everybody thought that the more you breathed it [radiation] and drank, the healthier you were and the quicker you would get cured from almost any ailment. All false, but that was the belief.

The reason that was the belief is that people, once radioactivity was discovered, they then discovered that a lot of the traditional health springs and spas, which had been in use for centuries, if not millennia, were a little bit radioactive. Stuff coming out of the ground, radon, the stuff dissolved in water, it made sense. They presumed that the reason people got so healthy going to the springs, which I think was not really documented, must be because of the radioactivity. Therefore, if we could supply radioactivity to people’s homes in the way of drinking water, breathing, whatever, it would be a great seller. And it was. It was a huge business for decades, 1910, ’20, ’30.

There were a lot of devices that were made back then. The most common device was called a Revigator. It was a jug which was lined with radium ore and you fill it with water. Radium decays into radon and radon is a gas, so it can emerge out of the walls into the water, dissolved in the water, and then you drink the water. “It does everything for you,” the personal testimonials were outstandingly impressive as personal testimonials always are.

There was a lot of stuff like that, pro-health radiation and radioactivity. Then around 1930, the public began to wise up. I think the scientists and the engineers long before that realized that there is a limit to, if there’s any benefit at all—it was used to treat cancer, too, way back then. They gave high doses of radiation to cancer tumors way back in the early days. But then the pendulum swung. We are now in an era where I think some people believe that that single atom of plutonium is fatal.

I have just got all kinds of stuff representing that. After World War II, atomic and nuclear was very positively perceived, and some people made salt shakers in the shape of Fat Man and Little Boy. Little things, all kinds of stuff. They made jewelry out of uranium ore that people were very proud to wear, all kinds of stuff. It helped sell your product if you said the word “radioactive” and “nuclear” and “atomic.” I collected a lot of that kind of stuff. Those are the two main things.

Then of course, recently, it’s been very anti. I have got a lot of buttons, anti-nuclear buttons that say all kinds of cute things. But the stuff that’s most interesting is the pro-health stuff from the early days, and then the euphoria over anything nuclear after World War II.

Kelly: Since you have tracked this, when did the pendulum swing the other way?

Shelton: Even in the ‘40s, people were promoting health spas and radiation doses. It was maybe the ‘50s or ‘60s. It’s interesting, I collect all this stuff, but I am not really interested in tracking exactly when things shifted and why. When I talk to other teachers at the school where I taught about why the pervasive feeling is so anti-nuclear now, the answer I got that made sense to me was, “It’s the mushroom cloud imagery from World War II.” It can be very destructive. Radiation, of course, is incredibly healthful, in health and all kinds of engineering things now, but it can be destructive. For some reason, that image is more stuck in people’s brains than the other possible images. I’m not sure.

The anti-nuclear folks in Santa Fe that I worked with a lot, I would try to get quantitative about risk, I would try to talk about these accidents of the trucks going through town. Finally, I would get some of them to admit that, “Well, I suppose that’s true, that the likelihood of an accident which would cause serious harm is really close to zero.”

Then I asked, “If you accept that, why are you still so against anything nuclear?” I think I got an honest answer. It is because they are against nuclear war and nuclear weapons. Anything they can do to impede or just be against things nuclear, they hope will make it less likely that there will be a nuclear war. Now, I don’t logically see the connection between disposal of radioactive waste at WIPP and encouraging nuclear war. But they did. You know, “If you can dispose of the waste, then you can build more bombs.” I don’t think they are connected, but they did. I kind of understood their point of view. 

Kelly: That’s interesting. What was the other part of your question?

Levy:   I guess there was the collections. Do you have a couple of favorites in your collection that you want to talk about? Were there any artifacts that your students especially enjoyed seeing or using?

Shelton: The most dramatic for my purpose of illustrating changes in public attitudes was—some of these Revigators, these clay crocks that made water radioactive, had decals on them, which I can almost quote from memory. Again, I am interested in changing public attitudes, and the decals would say, “This Revigator will make the water as radioactive as the most healthful springs of the world.” That says a lot about public attitudes at that time. That’s why I loved these devices. “We love this stuff, it’s really, really good.” Those were fun to show to the kids. Kids like things that are dramatic. I have uranium ore, I have some beautiful, large, colorful pieces of intensely radioactive ore. That’s exciting for the kids to see.

We, of course, had a large cloud chamber. The kids would say, “What should we put in it to make the track so we can see where all this ionization that radiation makes?” It quickly became apparent that we didn’t need to put anything in it, that background radiation is so healthy that we don’t put anything in it now. You just set it all up, put the dry ice under it, get it all cold and look in there and “Pew, pew, pew,” you see tracks all over the place. They loved seeing that and trying to deflect the tracks with magnets and doing other little things that you would think might have an impact. That was very exciting for the students. That’s not historically significant, but it’s educationally impactful.

Cosmetics! The French were into pushing radioactivity in cosmetics, Tho-Radia, thorium radium, but they call it Tho-Radia, was the name of the brand, which may still exist today, I am not sure. But they actually made face powders which had radioactive materials in them. They had ads, a beautiful ad of a lady illuminated, her face being illuminated from below, very dramatic. The same faces occurred in ads for many things over the decades.

But the radiance that you get from using radioactive cosmetics was interesting. It has nothing to do with it, but it worked to sell the product. This was back in those days when it sold a product to say it was radioactive. Ointments, salves, toothpastes were all made with radioactive materials, not significant, but measurable. Those were fun things in my collection. Yeah, ointments, radioactive ointments. “Cures you faster” was the claim.

Kelly: That’s great.

Levy:   Do you think any of those items at the time were hazardous for people to use? You hear the story of the radium dial girls who got cancer. Or the ointments weren’t too bad and the radon—

Shelton: Okay. Were some of them actually hazardous? One certainly was. It was called Radithor. I have dozens and dozens of bottles, because that was so important in public attitude towards radiation. I have a huge collection of the bottles, empty. It was a solution not of radon gas and water—radon gas has a half-life of two or three days, and so after, as a collector, you are never going to find any left. It had radium dissolved in water. Again, people thought that the more you do this stuff, the better off you are in terms of health.

There was a very wealthy man whose name I don’t recall [Eben Byers], who in 1929, ’30, ’31, promoted this product. Maybe he was the man behind it, but he certainly told his friends about it. It was very expensive, I think a dollar a bottle, which in 1930 was huge. He drank a bottle every day, he would give it away to his friends, and he died two or three years after he started doing this. Because if you load your body up with radium, you are in bad shape. It stays in your body, because it chemically kind of looks like something your body might need. When he died, that is a marking point in a sense, historically. He was famous, and this product was famous. The public, I think, certainly had a chance to wake up and think, “Oh, maybe this can be overdone.” That’s a very interesting product.

There was so much radium in these bottles—I shouldn’t say “so much,” it doesn’t take very many atoms to be exciting—but one reason collectors love them is that the bottles that have not been rinsed out, you can measure the radioactive residue. If the cork is still with the bottle, the cork is loaded, because of course, the material soaked into the cork. The liquids dried out. So from a collecting point of view, a bottle with a cork and a label gets a premium price. It’s still hot and will be for another few millennia, since the half-life is 15 or 1600 years for radium. Fun for a long time.

Levy: Do you have to store any of your artifacts specially?

Shelton: Good question: storage. It goes back to alpha, beta, gamma radiation and what they do. Any product that I have that sends out primarily alpha and beta, they are almost all pretty small, I don’t worry about. Because alpha particles can only travel through no more than an inch of air, and there’s none of the energy left. Beta particles can go through maybe a few feet of air, but you have it on a shelf and you never get any dose to you from alpha and beta radiation from these things. Gamma radiation, you can. So some of my stronger sources, like the uranium ore, I don’t store in rooms where I spend much time, but that’s about all I do.

Here is the one thing I do worry about, and perhaps I haven’t done my quantitative homework even enough. But things that emit a lot of radon gas, then I’m going to breathe it and then it’s going to be inside my body. As I said before, internal materials that are radioactive are much more hazardous than external materials. Things that emit a lot of radon gas and things that are particularly intense, like the ores, I keep in a shed outside the house.

Shelton: I have really enjoyed taking some of my students to the hospital in Los Alamos—this was quite a while ago—where they have the facility, which is the best—at that time, anyway—for detecting how much plutonium do you have in your lungs or in your body. You know about those rooms?

Kelly: No.

Shelton: There is also one down near the WIPP site. The game is again to have a room with no background radiation, because the radiations from plutonium are mostly alpha, which won’t get out of your body and won’t get through the air, so you can’t detect it. Then there is a little bit of fairly weak gamma or X-ray radiation. That’s what you have to look at: low probability, low energy, hard to see.

You need to have as little natural radiation coming from all around. The way hospitals have done that—I suppose it could have been done underwater, but I don’t know of any underwater facility—what they do is, build a room which has walls, floors, ceiling, door made out of four or six-inch thick steel. Mass is what helps more than anything else. Doesn’t matter too much what the material is. They use six-inch thick or four-inch thick panels.

Here’s the thing that’s really interesting. It has to be old steel, because all steel and all products, all materials in our world have contamination from atmospheric weapons testing. If you want really low background, you can’t just buy lead or buy steel, because it has a very small number of atoms in it. What they did is to find steel that was manufactured and refined, etc., before there was any atmospheric testing, which means before 1940 or ’41 or whatever, so, or ‘40, whatever the date is. What was the date of Trinity?

Kelly: ’45.

Shelton: ’45, excuse me, of course, I knew that. What they do is generally find old battleships, which have steel plates that are like this and cut them up, make them into rooms and doors. The hinges on these things, I mean, it was such fun for the kids. They have got to be really well-lubricated, of course, and the inertia is just phenomenal. But it is possible, you got to be careful not to pull for too long, because then it’s going to keep going.

But we were able to put one of our students—they asked for a volunteer, and one of our students went inside. So that’s the first thing: keep away background radiation. The patient lies down on a bed. Then there are a whole bunch of the most sensitive detectors for low-energy gamma rays that are arrayed all around the person, the body. You have to be in there for quite a long time to accumulate. These devices can measure the energy of each gamma ray and only look at the ones which they know come from plutonium. There are all kinds.

That’s the way you do it. In this really fancy and it’s a weird room, they bring all these tubes down close to you. They don’t touch you, but they are looking for the gammas coming from you.

One of our kids did it. Of course, they found no plutonium. They found potassium, because we are all full of natural radioactive potassium that puts out a low-energy gamma ray. The girl was alive when not contaminated, our student who was in there.

Kelly: That’s great. You wonder if an older person had been the subject as opposed to a very young person, an older person who lived throughout the atmospheric testing, whether there would be more plutonium.

Shelton: I would be quite certain it’s undetectable. 

Kelly: It would be?

Shelton: I mean, I’m not an expert on that.

Kelly: Yeah. Just curious.

Shelton: But I think you need to actually be—well, I don’t know the numbers. But I doubt it very much. Because we are talking about—well, here’s one reason why. The amount of plutonium in the environment and in our bodies has been going down, both because we take less in and we flush some of it out. The number I recall is a body burden of, on the order of 100,000, and I think it’s less than that now, but the average body burden for Americans. The half-life of plutonium is about 24, 25,000 years, I think.

If you have got 100,000 atoms in you, you’re going to get maybe four decays a year. If you hop into that room and lie there for an hour, nothing is going to happen. No plutonium is going to send out its gamma ray to be detected.

I think that’s the answer. You have to have way, way more than we accumulate from our environment to have any chance of detecting it, and of course, any chance to have any health effect.

There are some interesting applications of radioactivity in the environmentCarbon-14 dating, which can be associated with tree rings. But carbon-14 dating doesn’t work for anything that’s only 50 or 60 or 70 years old, because of the substantial change in atmospheric carbon-14 caused by atmospheric weapons testing. It still is fine for older stuff if it hasn’t been contaminated. Carbon-14 dating has to be done a lot more carefully now, because we have added so much carbon-14 that is not the natural steady produced rate from cosmic rays hitting the upper atmosphere.

Tritium also exists naturally in our environment at a fairly low level, but large amounts of it are created and released in atmospheric weapons testing. I think tritium has been used for discovering fraudulently dated wine. Wine has got a lot of water. Water is H2O, it has got a lot of hydrogen. Therefore, if there are any isotopes of hydrogen, like tritium and deuterium, they will be there. If you look at the tritium content of a wine that claims to be seventy years old or 100 years old, it should be whatever the natural concentration was back then before we changed it with atmospheric testing. I suspect that there have been some wines that have been fraudulently promoted, and that’s a very clever way to detect it.

Kelly: Just in case you have talked about this with your students, you know hospitals take great care if there’s a radioactive material to dispose of it appropriately. But a lot of those diagnostic tests that inject radioactive material in people, it gets disposed the natural way. Do you want to talk—

Shelton: Oh, I know a whole lot about that.

Kelly: Okay, good.

Shelton: Because, that was another one of our big projects.

Kelly: Oh, perfect.

Shelton: There have been a bunch of them. One project which we could also talk about I will mention first was, people in Santa Fe being worried they were being contaminated by the air emissions from Los Alamos. What isotopes might we be able to detect? We did a whole project around that.

Here is another one. There was a newspaper article, that’s how these things usually started for me. For decades, there was a laundry in Santa Fe which laundered radioactive contaminated clothing from LANL and power plants and research labs or whatever on [inaudible] Road. It was there for decades. I knew about it decades before it became a public issue, and so did a lot of other science teachers. You know, “Well, that’s interesting.”

Suddenly, it jumped out. Of course, people not being quantitative got worried about it. “Where is this radioactive material going?”

“Well, it’s going down the drain.”

“Where does it go?”

“Well, it goes down to the waste processing plant down on Airport Road in Santa Fe.” “

“Oh, well, then where does the water go?”

“Well, it gets used to water polo fields and soccer fields.”

“Oh, my goodness, my children are playing soccer on plutonium contaminated grass!”

It was a huge deal, of course. I and my students were sort of observing this and speculating about it. It took me more than a day to think, “You know, we can yell and scream about this forever. Somebody ought to measure how much is down there.” I mean, the mechanism is there, of course, there are going to be atoms down there.

We launched that project, and it was a huge project for a couple of years for us. Among other things, we went down to the fields and sampled the soil and brought it back and measured it. The state actually got involved towards the end, because they were scared, too. Everybody said, “What is the state doing about this?” We would collect samples jointly with the state on these playing fields and mixed the sample and split it. It’s a good scientific technique. They would measure it for the things they wanted. We did some of the same. We could compare and see if we’re getting agreement. We always did get agreement. They were able to do some things we couldn’t. So we had split samples with the state.

We collected samples. Then people started worrying about, “Well, maybe it’s not just in the water, maybe it’s in the sludge,” which of course it would be. They take the sludge from the processing plant and dig it into some acres of fields. It just sits there and decays and morphs or whatever. But there are these fields—which are not used for growing things, and people don’t normally have access to them—that are very smelly. That’s where the sludge goes. We also took a tour of the processing plant, and we got direct samples of sludge and of water directly from the plant. They dipped down in and picked it up. It was very exciting for the students and me.

We analyzed all this stuff. Number one, we found a huge amount of radioactive iodine from the hospital. That was by far the most radioactive material. Iodine is a beautiful material for diagnostic work with thyroids and for therapeutic work with thyroids, and maybe other things, too. There are some other things that hospitals use, which have short half-lives. Therefore, I believe the general standard is, you don’t have to do anything. Of course, people who have iodine in their bodies excrete iodine and that goes right down to the processing plant.

We saw iodine all over the place. It was the most exciting, easy-to-see radionuclide. But we looked for the others that should be coming from the laundry, looked for uranium and plutonium, and I forget all the ones, cesium, strontium, things that might be related with nuclear reactors and with LANL. I think, as I recall, the only isotope that we saw that could have been associated with the laundry was cobalt-60. That was interesting, because that is a waste product from fission reactions.

The question is, “Well, how much is there, and how do we figure out where it came from? We did the obvious and that is to take samples on the playing fields where the water is, and take samples on the desert and the dirt around these playing fields where the water is not used, and compare the cobalt-60, I think it was, content. They were indistinguishable. A lot of noise in the data, but there wasn’t more on the fields than there was any place in the environment. It was related to, I think, atmospheric weapons testing, again, very, very low levels.

We had an upper limit on plutonium from, I think, the work that the state did. You know, it can’t be bigger than X or we would have seen it. Then we did calculations on health consequences. “Suppose there is that much plutonium and cobalt, and suppose it is from the laundry, what did it do to you?” I don’t remember the results, but of course, it was utterly, utterly, utterly negligible. Anything you do, like traveling down to the soccer fields to play, is much more likely to kill you in a traffic accident than is the exposure to the materials that are there. It was a really, really clear result.

I testified with those results when this issue was really hot, and this was one of the most educational moments for the students. Some people in town got really upset at me. They wrote letters to the editor. They wrote a letter to the head of the school. There was an article in one of the newspapers claiming that I absolutely should be instantly fired. “How can we possibly have somebody like this as a science teacher in Santa Fe?” And just went on and on and on. It was very ugly. 

I went to the head of the school. The kids—and again, this was really educational for the students. They had done the work with me, and we just measured it, we just reported it. And this happens when you do good science? Well, sometimes it does.

The head of the school said—particularly in response to the letter that was written to the school, it was just, “Fire him, fire him, he’s a disaster.” His suggestion with that and the newspaper stuff is, “Don’t do anything. It will blow over, and trying to defend it or writing”—I don’t know, I think it was probably a good choice. It just blew over. We treated it as an educational moment for the students. “Look what happens. Isn’t that interesting? I wonder why they think that.” We made a big discussion out of it. That’s how it ended.

Ultimately, the laundry left town, not for a few more years, I think. It just was politically hard. There were all kinds of things, lawsuits and stuff. It was not science-based, the consequences, but they are not there anymore. For a while, they had that as a way station, where they collect laundry and then take it someplace else to wash it, but I don’t think it’s there at all now.

Kelly: On a similar note, I have heard a lot of people claim, and we heard one in an earlier interview, that they had seen various strange glows at Los Alamos. People at Taos were saying, “I see this strange glow at Los Alamos.” Other people in Santa Fe were sure that the waters coming down, the runoff from the mesa, is carrying toxins and radioactive material to Santa Fe. Not being a resident here, I haven’t followed it all that closely, but could you, with your—

Shelton: I have not heard about the glows, but I am absolutely sure that any glows up there are due to street lights and fires and fireworks and whatever, not nuclear.

In terms of contamination of water, yes, of course, you can find plutonium items in the drainage and you can find them everywhere. I am sure there are more in some of those drainages. The question is, how many are there and what is the potential health consequence? Again, we can measure single atoms these days, so the existence doesn’t mean there’s a problem.

In my opinion, as a society, we need to assess the risk and decide whether the cost of cleaning that up is the biggest bang for the buck in terms of saving lives compared to other things. What I think I have read about the water contamination is, yes, it’s there. Actually, I’m not an expert on water contamination up there. I am much more knowledgeable about air, because there were worries in Santa Fe that air pollution—we had another big, big project where we collected soil samples, surface samples all over Santa Fe, and ultimately all over New Mexico and upwind as well as downwind, because we had to try to answer the questions. 

We got a list of the radionuclides that come out of the chimney that’s associated with the linear reactor, which is where most of airborne stuff originates. We looked at all the annual reports and studies that Los Alamos does all the time about what the emissions are. It was clear what was there, what might be detectable.

We detected beryllium-7, which is one of the things that comes out the stack. I think I have got the isotope right. We got so excited that we actually might have finally measured something! Because usually these experiments are all null, you don’t find these things. But we did, we found beryllium-7.

I talked to the head of the school. “How are we going to announce this? How are we going to handle revealing this information? Because it’s going to be really sensitive for all kinds of people.” We did more measurements, and then at some point I called a scientist at LANL that I knew. LANL has been really helpful for Northern New Mexico high school and probably elementary school teachers, too, and middle school teachers. Through various programs and that help, I knew some people up there. I was talking to one of them—I don’t know if I called him about this—but I mentioned that we had detected beryllium-7.

The idiot that I am, he said, “You know, Jay.” He was a perfect teacher. He didn’t say, “Oh, I know what that is.” He was a perfect teacher, and I try to be the same. He said, “Oh, very interesting. I think there’s some beryllium-7 that’s natural in the environment that comes from cosmic rays hitting the upper atmosphere. So you ought to look into that.” That’s all he said. He didn’t say, “You’re an idiot, Jay.”

We looked into it, and that’s why we went and collected samples upwind and downwind. If it is from Los Alamos, there ought to be more of it downwind and other places. We had, on and on, and it turns out, yes, we were seeing beryllium-7 and, no, it was not any higher in concentration downwind from Los Alamos than any place else. We got samples actually internationally. Some of the kids went away on vacation and brought back little soil samples from I don’t know where. They had fun. We had fun. They all had beryllium-7, and it’s natural.

We did not detect pollution from LANL and Santa Fe from the air. We sure had fun trying, and we sure learned a lot.

Shelton: I wish science education was better in this nation, for all kinds of reasons.

Kelly: Yeah.

Shelton: And critical thinking. I did what I could with the kids I had. But most people don’t think critically and don’t know enough science and don’t try to be quantitative. One of the courses I taught last year after retiring was, the value of being quantitative in any environmental or health issue. It is so interesting to get numbers.

There was an article about, “Bacon will give you cancer. Studies been done that says you’re going to get a 20% higher risk of getting colon cancer if you eat two slices of bacon a day.” Well, of course, I decided this would be fun to look into. The most important thing in health claims is the 20% increase. A 20% increase over what background rate?

If you find out what the background rate was, and then you do all the numbers, it came out to be something like: if you got 10,000 people who do or don’t eat two slices of bacon every day for their lives, 9,000—I think maybe it’s 999 of them will have no consequence at all. One of them might get colon cancer because of it. You think about your life, “Here I am, do I deny myself the pleasure of bacon for the rest of my life, or do I eat two slices every single day? Maybe I will just do it once a week, then I’ll have one chance in 100,000 or a million. Is it worth it?” Well, it might be. When you put numbers on it, you can make a logical decision. “Oh, bacon, can’t do it anymore.” Well, no, it’s not true. How did we get on bacon? 

Levy:   Maybe this would be a good segue into talking about the importance of STEM education.

Shelton: I really am grateful to Los Alamos for the help that they have given to all Northern New Mexico people who want to avail themselves of it. I don’t know whether the programs are still going on now, I hope they are. But the most life-changing program for me: they had a program where you could apply to spend eight weeks in the summer working on a research project with a scientist.  That’s my kind of project!

I don’t want to talk about teaching, I don’t want to teach about teaching, I want to do science and then see if it applies. It really was because of that, I did that and I worked in the environmental group, and my particular task was finding out whether it was plausible to use gamma ray spectroscopy instruments to detect what levels of plutonium in soil. So I did it, and it was cool. I had all kinds of contaminated soil and did all kinds of measurements.

The main thing is that I got to know people and people got to know me, and it opened up doors. Some of the instruments that we used in some of these projects I have described are very sophisticated instruments. I was able to borrow from Los Alamos. Not all instruments are in use all the time. It made, actually, all of these projects possible, the radon in water and the contaminated soccer fields, all these things, the beryllium, had to use instruments that high schools can’t afford to have.

They had many, many programs for developing curricula, nuclear curricula. I was involved with some of those for all ages, between K and 12. Very active, very useful, very important in all of my nuclear activities. I couldn’t have done it without the lab.

Most present-day health standards relating to radiation dose presume that there is a health consequence, no matter how low the dose is. Now, as we talked about earlier, below something on the order of 10,000 millirems, it’s unmeasurable. But maybe it’s still there, unmeasurable because there’s so many cancers anyway, that you can’t see any increase from a dose that small. But maybe there is an effect. When you are looking health consequences to large populations, if you have got a million people who have been exposed to one millirem, that’s a million people millirems of radiation dose and so there should be some cancers out there. If, in fact, there is an effect that’s linear with dose, that it doesn’t matter how small, it’s still there. You can’t measure effects due to radiation below whatever this number is, 10,000 millirems.

That’s not a fact. My understanding is that it’s a regulatory policy that since we don’t know and we want to be conservative, we’re going to do our calculations assuming that it’s there. That’s a policy which you could discuss and change. You can’t change science, but you can change that.

Does that address all the issues you were asking about?

Kelly: That’s great, because the logical next question is, how clean is clean enough when you’re thinking about cleaning up radioactive contaminated waste sites, for example.

Shelton: Yeah. I think that’s a bad policy to have, because when the doses are that low, if the effects are unmeasurable, they are negligible. Now, maybe that’s not quite fair. I actually, I don’t fully say that, but I almost feel that way. But the problem is the cost, that if you have a contaminated area after a reactor accident or if somebody does a dirty bomb someplace or whatever, how are we going to decide how clean is clean enough, and when people can move back in again? The cost implication of assuming that the effect of the dose never drops to zero but is always there, is gargantuan.

I think it is bad policy. We haven’t had to face it very much. I mean, at Fukushima, they had to face it a little bit, and I think they have raised a little bit and become a little more reasonable about when it’s safe to move back again. But I think that in the future, that if we have some major event with very costly real estate like a dirty bomb in the city, I hope that the society is going to wake up and realize, it is fine for everybody who’s there to get an extra thousand millirems every year. It’s not going to result in a detectable impact.

Or even if you assume that there is an impact at the low doses, how many people are going to die from cancer? If you’re going to be quantitative, yes, every life matters, but every life is not worth $100 billion. We need to sort of be a little bit quantitative about whether we spend it on preventing lives, one or two that we don’t know are really there, or we spend it on hospitals and healthcare and things where we know there’s an impact, or immunizations.

It’s just dumb and ineffective for societal health to spend gobs of money on something which is going to have an unmeasurable and at least negligible, if not zero, impact. I think it’s terrible, and I hope it changes.

I just will mention, because it’s interesting. Another complete topic that I discovered the other day [1:51:00] where people are not being quantitative is the garbage patches in the Pacific Ocean. You see images, people talk about floating flotsam and all kinds of stuff, and you these pictures of mounds of garbage.

I did a lot of work on that last year in preparation for a course. If you were to sail a ship through that, you would be lucky to see anything, is what I understand. In order to measure that there is plastic and garbage there, you have to troll. You put these nets behind the ship and you pick them up and you empty them and you keep doing that and you’re measuring it. The average density is very, very low. Most of the pieces are invisibly small to the naked eye looking over the ship. All the pictures—occasionally you’ll find a big fishing net, I mean, I’m not saying there’s nothing out there that you can see. Occasionally, you might find a plastic bag.

The pictures that you see of mounds of the stuff are, I understand, all taken in bays and rivers and coastlines, where it piles up. They are not pictures from out there. It all started with one person reporting in an exaggerated way what was there.Now, it doesn’t mean it’s not a problem necessarily. Little bits of plastic, you worry about them and stuff, but the visual imagery which everybody has is wrong, I believe, based upon what I tried to learn last year. It is hard to find research papers, as opposed to advocacy papers, in a lot of these areas. But that’s one.