Donald Witters

Zierler:

OK. This is David Zierler, oral historian for the American Institute of Physics. It is April 30th, 2020. It’s is my great pleasure to be here with Don Witters. Don, thank you so much for being with me today.

Witters:

Thank you.

Zierler:

All right. So first can you tell me your title and your institutional affiliation?

Witters:

I am with the Food and Drug Administration, Center for Devices and Radiological Health. And my actual title now I think is Senior Review Scientist, but my background is biomedical engineering and physics.

Zierler:

OK. So let’s go right back to the beginning. Tell me about your birthplace and your family and your early childhood.

Witters:

[laugh] Wow, ancient history.

Zierler:

[laugh]

Witters:

[laugh] Actually, I’m local here. I was born in Washington Sanitarium, which became Washington Adventist down at Takoma Park, lived here all my life. I like this area.

Zierler:

Are your parents natives of Washington?

Witters:

My father was. He was born in the District, and raised in the District in D.C., northwest. And my mother actually was born in Atlanta, Georgia, and raised in North Carolina, a very small town in the sort of western part called Spruce Pine up in the mountains. She was in a small family: nine kids.

Zierler:

[laugh]

Witters:

And I had plenty of uncles, mainly aunts, and cousins. They’re spread out everywhere.

Zierler:

Where did your parents meet?

Witters:

I’m not sure exactly. Probably down in the District or somewhere in this urban Maryland area.

Zierler:

So what brought your mom to the Washington area?

Witters:

Work. [laugh]

Zierler:

What was her profession?

Witters:

Well, she actually came up, I think, towards World War II. And with at least one or two of her sisters worked at Marriott Hot Shoppes for a number of years. A lot of friends that she made there that she kept for all her life.

My dad was basically an only child, and he grew up in the District, went to some of the schools. You may be familiar with Coolidge High School. And during the I guess ‘30s and ‘40s, he got drafted into the Army after World War II, served some time down in Panama Canal where they still had a fair amount of build-up.

And went to the University of Maryland when all the G.I.s coming back from World War II were flooding the universities. And they set up Quonset huts in some areas to carry the capacity. When I went to Maryland, they still had some of those Quonset huts, and they were still using—

Zierler:

[laugh]

Witters:

Since then, the last visit I went down there, I don’t have much occasion to go down there, they—it’s hard to believe the changes since I was there, but that’s almost 40 years. Oh, jeez, it’s over 40 years now.

Zierler:

Now did you go to public or private schools growing up?

Witters:

I went to the public schools. But they were experimenting when I was going through what used to be called junior high school and high school. And I got fortunate to go to John F. Kennedy High School just up here in Randolph Road when they were experimenting with an open campus.

They didn’t have any bells. And it became clear in that experience that it was more like what was going to be expected beyond that: college. You have to decide when you’re going to class and where you’re going to class, and your own schedule. And there’s no bells in college.

And the teachers, some of them were a little—you know, this was sort of at the end of the big hippie period. And some of them were very, very free thinkers, to say the least, especially the chemistry teachers. [laugh] Some of the English teachers were really, really good, very interesting, and very good at motivating people.

And I really got into some of the sciences, first physics class. I took some practical things like typing, which I wasn’t sure I’d use. But it’s become one of the things that you’re expected to do now, so I’m glad I took that one. But I loved to take print shop too. That was really fun. I really liked that.

Zierler:

Now were you an outstanding student in science? Did you distinguish yourself in high school?

Witters:

No, not really. I did enough to get into these classes with the math and the science, but not anything all that outstanding. I didn’t join any of the clubs or anything. I’m just not a particular joiner for things like that. But, yeah, I tried out for a few things like basketball. Didn’t quite make that. So I concentrated more on doing the classwork, and I used to get a lot of time in the library, not always studying.

Zierler:

[laugh]

Witters:

Our library was pretty interesting. But when I got down to Maryland, I would spend hours in the stacks just looking at some things. I loved to go through the old LIFE magazines, and look at those, and just—yeah, I loved LIFE magazine anyway. That was great.

Zierler:

So did you apply to a lot of schools, or was Maryland—that was your spot? That’s where you wanted to go?

Witters:

Maryland was pretty much that. In those days, it was still—the way classes were and the way you signed up were still the old style in the big gym. Here’s a table for these classes. And the guy had a pencil with a stamp on the end, and would stamp your paper, and stamp his paper. It was a different experience than it is now [laugh] a lot different.

Zierler:

Sure. And when did you decide on a major?

Witters:

That I wasn’t clear about. [laugh] I took the orientation, and I have no idea how they managed to get me put into the school of nursing for orientation. And, well, it wasn’t what you call a male area at that point. And that was always, you know, just one of things.

But I went into the school of—what did they call it—the arts and sciences. Yeah, they were reorganizing the university too. So I wound up in a division of physical sciences. And that gave me a background that was much broader because I didn’t know how much I wanted to get into. Except certain areas—I was never good at languages—required certain languages.

Chemistry required either German or Russian. Some of the other ones required certain languages as well. And the computer area was just starting to really ramp up. So I looked at that. And I also took a course [laugh] that I thought was really interesting in weather, which was interesting, meteorology.

And with all of the electives, I decided to take one at night, which I found on contract law, which was fascinating that I thought about that. Taught by a lawyer with older people generally in the class, which made it a lot better I thought because they were mature, and they didn’t have any problems with speaking up and asking questions. You’re kind of intimidated when you’re in class, you know, a freshman in particular, or being in these large rooms for physics.

I mean, that was—those basics physics classes were, you know, probably 100-plus people in that, and the chemistry and classes like that. I really enjoyed those types of classes in high school at least the physics class was really interesting, and sciences which they offered. The chemistry was fascinating as well. I got to be fairly good at tritration of acids and bases. and could just barely make it so it would be just a little bit on the edge to turn the indicator color and just one more drop would really turn it to the color. Anyway that was a lot of fun.

Zierler:

So what major did you ultimately declare?

Witters:

They had made a new major called physical sciences, which allowed me to get physics, engineering, math, some chemistry, and enough of that that they would make that a major.

Zierler:

So obviously the emphasis there was breadth not depth, since you were doing so many different kinds of sciences?

Witters:

Yes it was. But really got lucky with a couple of professors. One older gentleman in the physics mechanics class, was really good at, “Here’s where we start, here’s the derivation,” and taking you right through it

Zierler:

Do you remember his name?

Witters:

No, unfortunately, I was wracking my brain last night to try to remember this gentleman’s name. I can remember his face. (I recalled his name later: Professor Myers, an excellent teacher and mentor.)

Zierler:

[laugh]

Witters:

Back then the professors especially in those areas, you know, dark suits, dark tie, white shirt type of thing. But he was one that loved, you know, teaching, I could tell. (Professor Myers) He was doing some research, but I never got connected with that. But I would come to his office, and we would just—you know, he’d walk through some of the class examples and homework so it was clearer to see.

One of the things I remember is in the classes towards the end when we were studying some of the electromagnetics, he walked us through a derivation to get to Einstein’s famous E = mc2 equation, which was fascinating where that came from. Of course, it wasn’t as in-depth as it possibly could be, but it was fascinating to do that.

Zierler:

Did you have a senior thesis?

Witters:

No, they didn’t require that at what I was doing. I was trying to get as much and as wide as I could.

Zierler:

So in terms of your exposure to bio and chem and physics and engineering, was there any one that you particularly gravitated towards?

Witters:

No, I thought the physics was interesting. When I was going to elementary school, I think it was fifth grade—yeah, fifth grade—one of our assignments was to interview people in areas that you might think you might go into. So my dad arranged that—he was working with NASA over here at Goddard. He was a mechanical engineer. He became a systems manager, I think, on the satellite program. Before the Hubble, he was working on an Orbiting Astronomical Observatory; OAO they called it. It looked like a washing machine. And in those days, NASA was very much into PR because the space program leading up to Apollo and the moon landing was really a big thing. And they had a pretty extensive budget for PR.

They made films. My father would come in to talk to the class, bring the films. They had these little paper models of these satellites that he handed out, and you could make them. They had open houses that were fantastic that we went to.

And this OAO looked like, like I said, a washing machine. And it was essentially what Hubble is, only not quite as big and precise as Hubble has been. Unfortunately, when they put it up, the first one, some issues came up, and it really didn’t last as long as they thought it would, as long as they designed it to.

I’m not sure what happened after that. And there were several Earth satellites, geographical satellites, and some others that they were putting up at that point. I remember getting up really early one morning to go over to Goddard and watch the launch of the OAO he’d been working on it for long. And it was like 2:00 in the morning or something.

Zierler:

Do you remember what year that would’ve been?

Witters:

Later ‘60s if I’m thinking about it.

Zierler:

But before Apollo?

Witters:

Well, before Apollo hit the moon, yeah, well before that. NASA had, and still has as far as I know, a really significant program in that non-manned area. And I always wanted to get into that area. I thought it was fascinating. But that was not to be.

But I always thought it was interesting about that, the satellites and how they built that, and then what they did with them, and how they calculated the trajectories and the Earth orbits, and what they were doing with them. It was just fascinating to me. But I didn’t quite get into that area.

Zierler:

So what year did you graduate Maryland?

Witters:

1975.

Zierler:

OK. And then what were you thinking afterward? What were the opportunities that you wanted to pursue? Were you thinking about graduate school?

Witters:

No, that part hadn’t hit my mind at that point in time. That hit later when some opportunities came about when I was with the FDA. I got lucky. I went to a counselor, and they sent me to a couple of interviews for researchers who were looking for a student to help on their programs.

I went to one who was studying geology. That didn’t really work out. I knew that wasn’t going to work. And then I went to one with Howard Bassen, who I’m amazed is still with us in the FDA. He was one of my mentors, a brilliant engineer, one of the best I’ve ever worked with.

My other mentor was Bill Herman who was retired a few years ago. And I just got lucky between the both of them because Bill was in MENSA (an organization of high IQ individuals), and a very brilliant guy who really was more interested in mathematics. Unfortunately, for whatever reason, he didn’t get a chance to finish up on his graduate degree in mathematics.

But he taught me the need for thinking larger than what’s in front of you and look well into the future about things. So did Howard. Howard a few years ago got the Engineer of the Year award from FDA. Well, well deserved, well deserved. A long career in the Center.

So I got lucky ‘74 after working in various jobs that kids usually work in, stocking shelves in a pharmacy, selling appliances, and got this interview with Howard, and he took me on. At that point, they had different ways of taking students on that are a lot easier than they are now. I became fascinated with his work.

He was developing a miniature instrument, a miniature antenna probe to go inside of the body actually—most of it was experimental in tissue stimulation—and actually detect the electric field inside the body. And he had worked on that for years, and got a patent or two out of developing that. And I was doing a lot of the experiments that led up to that.

It also turned out that one of the professors that I hadn’t had much contact with was on contract with us to work out the theoretical modeling for that, for the electric fields inside a body. And he was really good. His name was Augustine Chung. He later broke off, and formed his own company developing some equipment that was used. We bought some of that equipment later to perform some experiments.

Zierler:

Now when Howard took you on, how did that work in those days? Did you come on as a federal employee? Was it an intern program? What was the arrangement?

Witters:

Well back then, they had what they called the 700-hour appointment, which was at the discretion of the supervisors. Howard was an engineer in the group. Our supervisor branch chief was Mays Swicord who later stepped down from that position to go back to school and get his PhD in that non-ionizing human exposure effects and energy deposition and tissue dosimetry area that we were working on.

And they had several of those appointments they could give at a time. It just depended on their budget. So I wound up getting on one of those very short appointments, and they kept bringing me back. And I then said, “I’d love to work here.” And they found a position.

Zierler:

Where was the office located at that point?

Witters:

We were in Rockville in these warehouses that—it was—

Zierler:

Now when you say “warehouses”, did it have a temporary feel to it, or that’s just how it was set up?

Witters:

No, these were built as warehouses, single-story warehouses. Not gigantic open areas but smaller areas that you would see and still see in Rockville (the last of these were recently demolished and new buildings gone up) And we had a portion of that particular building we shared with the division office, which really was about four people, and another group that did ultrasound and mechanical types of research. And we also did enforcement (compliance) support. Well, we were the technical experts in microwave and RF areas to help the people who were doing compliance, the enforcement activity.

Zierler:

I’m particularly interested especially in these early days of the interface between policy and basic research. In other words, what was the environment like? Was it really a basic research where scientists and engineers were just pursuing things that they thought were interesting and important? Or were there really, you know, initiatives that came from on high that were sort of, you know, given to the scientists and engineers to work on because it conformed to some kind of a larger policy or enforcement initiative?

Witters:

The latter of that. FDA is a public health organization, which has specific laws that it is required and was organized to enforce. At that time, microwave ovens in particular were just coming into large, wide use in the early ‘70s. And under that act, the 1968 Control for Health and Safety Act, that was where our bureau was formed, covering all forms of radiation from the ionizing and nuclear to the non-ionizing, which is radio frequency, to the mechanical types of radiation for ultrasound, which was starting to really ramp up as well, particularly in medical areas.

We covered and still have authority over X-ray, CT (computerized tomography). MRI (magnetic resonance imaging) was just barely being looked at for medical uses, even though it had been developed years and years ago for chemical analysis. And lasers were ramping up in medical areas and products. Mercury-vapor lamps were a big issue.

Televisions, which were problematic for X-ray because the cathode-ray tubes were having some issues, that was one of the main drivers as I understand it for the formation of this law, which was really aimed at radiation protection, protecting the public from these really heavy-duty sources of radiation. I wasn’t directly connected to the ionizing radiation work. I came to learn that BRH had a colony of dogs—beagles, I think it was—that were exposed over a very long period of time and kept—and looking at their progression all the way to when they passed away naturally. They weren’t euthanizing these animals. This was a long-term experiment. Roger (Schneider) knows a lot more [laugh] about that.

Our division had a lab that we were associated with in Cincinnati that did nuclear radiation, primarily nuclear medicine, which was more widely used for certain things, cardiac imaging for example. And BRH had a lot of issues with the X-rays, especially the dental X-rays which, at that point, were again one of the drivers because the exposures were all over the place. And that was a major, major problem. You don’t want to go to the dentist, and get X-rays that are massively more energy than you need.

Early on also—I don’t know if you’ve heard about this, but back in the early days of X-ray, they basically—when Wilhelm Röntgen, and others developed these systems, if you have ever seen them, they’re basically the X-ray tube sitting out in air. No shielding of any sort. So people that were doing that, doctors were having major problems because their hands would be in it, and their hands would start getting burned. And these kinds of burns don’t heal very well. The X-ray burns are really problematic, and a lot of other things too.

It all—you know, there was a progression, and of course the nuclear tests that were being done in the ‘50s and ‘60s, and that was one of the drivers for the beagle program and some other ones that they were tied into. So it was a lot of radiation related research and regulatory work, but our area was microwave, particularly microwave ovens. The Food and Drug Administration, probably unknown to a lot of people outside of that area, has actually the authority under that act, which has now been folded into a larger FDA Act, to enforce and try to reduce if possible but at least maintain public health for exposure to radiation sources.

They include everything, the whole spectrum of things. So it’s quite fascinating. I got in with Howard and Bill doing instrumentation work, doing this modeling work with Howard in developing that miniature antenna, doing work with others in that area.

Zierler:

So, Don, I want to ask, in terms of the research, how much of the research was geared specifically toward mitigation of known dangers, and how much of the research was just trying to figure out how dangerous the radiation exposures was? How did that play out?

Witters:

All of the research that I was involved with was targeted obviously towards these public health issues. We were primarily trying to develop and maintain accurate measurements in instrumentation to do those measurements. I eventually became the main person for calibrating instrumentation for doing the microwave oven, not only for FDA, which has field offices, but also for the states.

At those points, microwave ovens were undergoing changes and developments to reduces leakage . And early on they had some major problems with leakage. A microwave oven works because the energy that’s deposited from the generator that’s generating the microwave into primarily the water molecules. And it’s the interaction with the water molecules which happen to be a resonant frequency for that. And it basically heats up through friction of the molecule, and it heats deeper into the substance than just the surface.

It’s basically depositing the energy below the surface, and heating from there outward. So it was described as basically cooking from the inside out. It has its own issues, and we had to develop ways of making sure the instrumentation was properly calibrated, and we worked with the oven and instrument manufacturers. And there was only three or four reliable instrument makers at that point that were used by everybody. My lab experience grounded me as I grew in responsibility and I went out with some of the inspectors to do the compliance inspections at the plants in Japan and Korea, and in the US in all—

Zierler:

The inspectors were FDA as well?

Witters:

Yes, these were people in a different part of BRH, later our Center. Our Center Director, Dr. Villforth—well, I guess we were still BRH at that point. John Villforth had a background in public health, primarily ionizing radiation issues safety.

Over the years, the ionizing radiation protection limits have changed, and generally in lower—getting lower as we find out more and more about that. I’m not an expert in that area. But my understanding is a lot of the work has some basis in the effects after Hiroshima, and also some of the effects from the sun radiation. Particularly when you’re up in a plane, you get a lot more up there in terms of some of the cosmic radiations than some of the X-rays that you do down on the ground, or if you’re somewhere below that.

So our job was really developing and maintaining the methodologies to understand not only how and measure how it’s coming off of things like the microwave oven, and maintaining the limits that were set in a standard that we developed for microwave ovens, but also looking at some of the things beyond that. What are these effects? How can we quantify the exposure? What does that mean in terms of certain tissues?

I was in a project with Dr. Gideon Kantor who was in our group looking at and developing diathermy, which is using radio frequency to heat up human tissue for therapeutic treatment. It’s been around for many, many years. But we went through a number of the older applicators, and found that most of them were really inefficient.

They would deposit—they would use, 100, 200 watts of energy, and they would deposit in the tissue a quarter of that, maybe. That’s if they use certain ones in these applicators. And they were using this for all manner of treatments, from internal, things like vaginal treatments, and external for muscular, neuromuscular types of issues.

As well as eventually it began to use that and find that cancer tissues can be extremely sensitive to heating. And combined with chemotherapy—this goes back several years—the research was showing a really good effect on reducing and even eliminating some of these tumors, which have very poor blood supply, which is what they grow and grow and grow to try to get, and very sensitive to heating from, you know, above the body temperature.

But it’s really tricky to get enough energy into the body in the places you want to get it, and preserve the tissues between the surface skin and the target. You don’t want to burn the skin in trying to get enough energy, say, into a tumor that’s 2 centimeters into the body, into the area below that, or organ-type tumors, or brain tumors. I saw some research that was out of France early on that was just remarkable.

They were treating inoperable brain tumors, with certain frequency hyperthermia, which is not easy through the skull, and had some remarkable results of reducing those tumor sizes in a relatively short period of time. And then when they combined it with chemotherapy and some of the other types of radiation, remarkable tumor reduction with is. So we were involved in that.

One of the things that Howard and the others were involved with—I wasn’t directly involved with—was developing a way to quantify the actual deposition of energy in the tissue, because every layer of the tissue is essentially a boundary type of problem. These are electric fields. Light and other electromagnetic energy is made up of electric and magnetic components. But the magnetic fields, particularly at the lower frequencies, don’t propagate very well, and the body is almost transparent to that at lower frequencies.

So there’s not much you can do with that (low frequency magnetic fields) if you’re trying to put energy in the body, unless you do certain things. The electric field is the primary component field that dominates the propagation. And that’s actually what radio uses is primarily the electric field. But the energy deposition is difficult to focus in the body; not easy to do with simply, oh, I’ve got an antenna that works with radar or radio, and now I’m going to apply it there.

No, that’s completely different how you want to design that antenna. So Dr. Kanter designed one that not only deposited a lot more energy into the target tissue, it was very efficient. He could do the same job with his antennas, that he eventually patented, with like a quarter of the power, and get 10 times or more heating and energy into where they were looking to put it in. The design also had a what was called a choke type of design around it, so that minimized the amount of leakage.

So not only would it be much more effective but much safer. You don’t want to spray leakage around to unintended tissue or the patient or user. If you’re treating the abdomen or somewhere, you don’t want to have a bunch of this non-ionizing radiation going into the eyes, for example, or going down into the gonad area.

We also did some work with some industrial products, which were interesting. They use high-energy radio frequency, lower frequencies, to weld plastics, dry lumber, mold plastics. There’s a whole range of things they use those for. One of the projects I had worked peripherally on was developing a way to measure that, and actually go out and measure it. Issues were being reported from stray radiation —women in particular tended to be the ones who were operating these industrial equipment—and looking at the amount of energy and where it was deposited.

And, of course, when we started looking at it, it was deposited in areas that were very sensitive to issues such as reproductive areas, areas in the legs and arms. It turned out that where the operators sit for the plastic forming and welding, and they’re grounded essentially, and a lot of the stray leakage can be coupled into them. The energy can go down through their body, and it gets concentrated in the form of heat sometimes in their legs and feet. And those areas in between were getting some fairly high exposures because they did this for hours and hours and hours. So that was interesting.

I worked with Howard a little bit on dosimetry because at that point we were doing a lot of work with animal eyes in particular and designing a system that Howard was primarily designing to expose them to a reasonably homogeneous type of exposure. And measuring with some of the probes that we were developing and calibrating inside of the little containers that had to be plastic because that’s relatively transparent to the RF field but it still can cause perturbation of the exposure. And measuring and trying to get the proper dosimetry for exposure of the animal the way that they wanted it so that they didn’t have to tie the animal down, and were able to move around with this exposure over these longer periods was the same.

Zierler:

Don, I wonder if you can talk about the flow of information, like as in how did research projects come to your bureau? Where did they come from in terms of the directives to work on these things? And once you established your findings, where would you send them off to? I just want to get a sense of the overall sort of flow of information in the policy process in all of this.

Witters:

Wow. Those are the kind of questions that Roger is probably better to answer. We were charged under the Radiation Control Act for and had the authority to promulgate standards for various products. Before I got there, they had promulgated standards for microwave ovens, X-ray equipment. I think they had the mercury-vapor lamp, and one or two others. I don’t believe at that point they had the laser standard had been promulgated.

So the FDA was given the authority to basically write these standards under that law. And of course, there’s a procedure that goes through that is pretty lengthy and onerous on FDA really. Since the ‘70s or thereabouts, maybe into the ‘80s, I don’t believe they’ve had the resources or support to promulgate any new standards. So there’s only a handful, six or eight maybe; maybe more.

As I said, it grew out of concerns and the problems and new technologies that were coming in the ‘60s. But I don’t know if you know or remember back in the ‘60s, color TV was just coming into its own. And they were using cathode-ray tubes, which pretty much have gone by the wayside now.

These cathode-ray tubes are essentially X-ray sources because they require a fairly high voltage to create that cathode ray that rasters across the CRT behind the phosphorous screen, and that becomes your picture. But back at the other end, one of the by-products of creating that picture is a fair amount of X-rays.

I don’t know if I should mention the name of the company that had the biggest problem. But there was a certain company that had a major problem because some components were not properly designed, and their shielding was not adequate. So they had major, significant leakages of X-rays that were exposing people watching them. Now that’s in addition to anything else that might be there.

But watching TV and getting a healthy dose of X-rays, well, unhealthy dose of X-rays is not good, not public health. And that was one of the drivers. The affordable microwave ovens came along in the late ‘60s. They had been a novelty. They early versions actually made it to the market in the ‘50s but they were very expensive. A microwave oven back then developed by Raytheon as the RadarRange, that’s where it came from, was about $3,000 or more. The average car was less than that.

Zierler:

Right. [laugh]

Witters:

The cost changed in the ‘60s, and in the early ‘70s. And through the ‘70s, microwave ovens were all the rage,. We worked a lot of that, and interacted on those many, many times with the manufacturers. And in a few occasions, when I came there and started working, we were doing measurements and research on the leakage from some of these really bad actors.

One of the original oven designs used a gasket, a metal gasket, to seal the oven. And some of these ovens were basically microwave oven inside of a regular oven below the stovetop range; called common cavity. So in addition to regular conductive heating you’d have both.

Large numbers of this type oven were leaking because these gaskets were not sealing it properly. And when they got dirty or broken over a period of time, even more leakage. So I started measuring some of that leakage. On some sample ovens I could get the microwaves on with the door open resulting in some really significant leakage.

Zierler:

So how do you do those measurements? Is it like a consumer reports kind of situation where you’re using the microwave the way that consumers would use it until, you know, the gasket breaks down, it gets dirty? And you’re treating the microwave as if it’s in a personal home, and you’re just seeing what’s happening as a result? Or how are you doing these measurements?

Witters:

Well, the standard was set up and came into being in 1971. I was there in ‘74, ‘75 as a student worker. The work that I was doing was essentially measurements and research with the standard technique. The method involves using a certain amount of water that represented enough of a thermal load for the microwave oven, and turned the oven on to max, max energy, and do leakage measurements around the doors and anywhere else that might leak.

And microwave ovens, depending on how they’re made and how well they’re made, can leak in a number of different areas. And comparing that against what the limit in the standard set at 1 milliwatt per square centimeter (* 1 mW/cm2), 5 centimeters, about 2 inches, from the surface of the oven, when it’s made. And they allow for oven aging/degradation leakage up to 5 milliwatts per square centimeter (* 5 mW/cm2) over the life of the oven.

We were looking at that with these ovens, and some of them you could literally open the door while the microwave was on.I was doing leakage measurements and calibrating the instruments. Bill and Howard developed a technique, based on some NIST work earlier, performing precision calibrations within a semi-anechoic chamber.

Later on, we were also engaged with NIST out in Colorado, and it turned out that because of our years of experience we could make recommendations for the NIST measurements that improved their results. They never admitted that, but we were showing them how to make calibrations of the leakage instruments more precise. And I always like that, I always chuckle at that because NIST is the acknowledged technical leader, rightfully so. There’s no doubt about that. They developed these techniques, but we perfected these for oven instruments.

But we had some tweaks that we were doing that made it more precise. And once they started seeing that, and changing it, NIST and BRH calibrations on the same instruments started aligning up a lot better. At that point, we were going back to the fundamental measurements of units of energy, and calibrating every part of the system.

The NIST technique issue turned out they had set up their holder for the instrument in a way that we knew by looking at it was going to be problematic because it was—well, let’s just step back a second. Radio frequency is not that energetic as compared to X-rays, which go through everything, as you know. X-rays are ionizing and energetic enough to penetrate or go through even dense objects.

RF and microwaves can easily be perturbed by objects and materials —anything other than a vacuum perturbs it. This is why we’re able to pick up radio signals from distant galaxies because there’s nothing really in space. That’s not exactly true but, by and large, in space the propagation is much greater and can see it.

On Earth, that isn’t the case. We have people, we have walls, we have everything, and the RF and microwaves bounces all over the place. They call it multipath. When you’re receiving a radio signal, even on your cell phone—the average user don’t know this but the phone has complex algorithms to take care of this—the signals are bouncing off of a lot of buildings and things, and the strongest signal that they can pick up is the one that you’re listening to. All of this is transparent to you but that’s part of what’s happening.

In the old days, if you remember AM radio, you could tell this real easily. If you pass certain areas, even on FM these days depending on what it is, certain areas you would get this really strong signal. If you go past it just slightly, it would degrade and, you know, you’d get static and stuff like that. AM is particularly bad about that. Except at night if the skies are clear because it’s bouncing off the ionosphere to get those distances, you could pick up—I was able to when I was a kid with an AM radio—pick up Canada stations hundreds of miles away. In the daytime, the sun can and atmospheric conditions really interferes with AM radio so you don’t get nearly as good reception. FM radio is a point-to-point type of system that is much better, and was designed that way, and developed that way, which is why everything has kind of switched over to FM by and large.

Zierler:

So, Don, I’m curious about the microwave. Was the issue of concern only the leakage, or was there something inherently problematic about the technology itself?

Witters:

It was primarily the leakage for public health; trying to get the exposure as low as we could achieve. They had this—they started sometime later using what they called ALARA, A-L-A-R-A, As Low As Reasonably Achievable. That mentality goes to this day and beyond.

It makes sense. You try to achieve something as best you can. The problem with that is it’s set in time, and your understanding and the science moves forward, and you understand that, hey, that particular level is not what you want to do. So you start trying to push the level of acceptability down a little bit to account for that, account for what the research is showing you.

Zierler:

And how are these thresholds determined in terms of, you know, the causation versus correlation issue? I mean, how are you isolating whatever health problems result from, you know, home microwave exposure versus any of the other reasons that people might be getting sick?

Witters:

Well, my understanding of what they did for the microwave oven standard was based on research in rabbit eyes, which are good models for human eyes. And the levels that they were looking at were producing cataracts, which is a opaqueness of the eye lens. In the case of microwave and other types of non-ionizing energy the lens is heated which doesn’t have a great blood supply so it doesn’t have the ability to dissipate this heat and this it’s thought to lead to cataract formation. Based on the research a threshold of what was thought to be safe was set at 100 milliwatts per square centimeter (*100 mW/cm2).

Experts determined to put in a 10 times safety margin, making it 10 milliwatts per square centimeter(*10 mW/cm2), and then an additional safety margin of another 10 times less down to 1 mW/cm2 because they wanted to measure the leakage at the product surface. If you’re exposed standing back from the emitting produce your exposure is different than if you’re standing right next to it. So hey decided that the measurement should be at 5 centimeters separation from the oven surface and was what they could reasonably achieve with the instrumentation.

There was only one manufacturer at that point making instruments. And they decided we will set this at 1 milliwatt per square centimeter at the oven, and allow that the person would be so far away from that, and their exposure would easily meet that 10 milliwatts per square centimeter. There are two frequency bands where microwave ovens can operate: 915 megahertz (* MHz), and 2.45 gigahertz (*GHz). These frequencies were set up many years ago by FCC and others.

And in those bands, they’re called Industrial, Scientific & Medical (ISM) bands—we work now in mostly the medical and the scientific—these are allowed to be used pretty much by anybody without a license. FCC has Part 15 of their regulations that allow this, and they have certain rules and regulations. But within those frequencies, those ISM bands, which have several bands that go lower and higher in frequency than that, you don’t need a license. It’s free. So there’s a lot of incentive to put things in there.

Your computer is now running with probably Wi-Fi or perhaps Bluetooth. They’re both in the same frequency range as microwave ovens, the 2.45 GHz. A leaky microwave oven nearby the computer will knock off your Wi-Fi and your Bluetooth as long as the microwaves are on.

Zierler:

So I guess I can be reasonably confident that our microwave isn’t too leaky because our Wi-Fi is good, and we’re testing it to its limits these days. [laugh]

Witters:

Well, during the time I was there, they went from this gasket type of approach for the oven leakage, which was a pretty simple, cheap, and gross way of doing it, to developing another technique that Dr. Kanter was using called the choke, which is basically allowing part of the leakage to return and cancel out a good bit of the other leakage that might get out. And if you load the choke with a certain loading material that absorbs this, then you have a very nice choke to basically choke out most of that leakage that might go out. So they started making the doors in the early ‘70s—this got picked up by all the major manufacturers—with this choke system, and it didn’t depend on metal-to-metal contact anymore.

It choked it out. So the leakage went really down, and it became less of a problem across the board provided the oven production was keep under quality control.

Zierler:

Don, can you talk a little bit about your role in terms of—you know, there’s you, there’s the inspectors, and there’s the manufacturers. How does this all work together so that the FDA is getting the manufacturers to do what they need to do?

Witters:

These standards are mandatory standards. They’re not voluntary standards. If you’re manufacturing a microwave oven, or some of these other products that we have these standards for, you have to abide by certain parts of that regulation, that standard. It includes reporting to FDA that you’re making the products, and the information is reviewed before the product is allowed to enter U.S. commerce and be sold .

The process includes inspection of the production facilities. It includes assurances that they’re able to make the leakage measurements, and keep the leakage down with properly designed, calibrated, and maintained instrumentation that we look at. It includes quality systems and good manufacturing processes and exporting along the way.

So we have a microwave oven manufacturer A. He’s decided, “I’m going to make a certain model.” He has to put in some paperwork to show us that he’s doing that, and how he’s going to assure the quality of that oven wherever it goes, for the life of the oven.

Part of the standard also says that they have to assure quality and leakage over over the product lifetime. One of our tests used to include set up of mechanisms that open and shut the door for a determined number of cycles simulating the oven use, and turn the oven on for 50,000 to 100,000 cycles to make sure. That takes a lot of work to do that. But that’s how it’s assured that they’re meeting parts of the standard. So it’s really essentially a quality assurance type of program that we are overseeing.

Zierler:

Now if a manufacturer is not compliant and, you know, you make the determination, or the inspectors or your bureau, that these microwaves are unfit for consumers to purchase, who are the other government entities that get involved to make sure that defective—and this is not just microwaves. This is a broader question. What are the partner agencies that get involved to make sure that these defective consumer products do not come to market?

Witters:

Well, primarily, FDA has the enforcement authority to essentially shut down the sale of the microwave oven products. And this has happened. I was involved in a few of these actions. Some of them involved US manufacturers that they basically prohibited from selling them, and they would have to keep them in their warehouse and provide a plan to bring the ovens into control. And in some cases, they’d have to take them back, and retrofit them.

In some cases, it involved products that were coming from outside the U.S., primarily Asia. And in a few of those cases we involved the Customs Service. Customs can basically embargo or seize, if that’s necessary. But that’s never totally happened with ovens that I recall.

Customs can stop them at the port of entry. And in one case, there was a ship that had a fairly significant shipment of these from their Asian manufacturers that we got the Customs people to basically quarantine until we were satisfied that they had done the appropriate corrects. It takes really significant problems in a number of areas to take those kinds of steps. But it has happened on occasion.

We were involved with making sure that our instrumentation, our methodologies were proper and accurate. One of the projects I was into with Bill Herman was evaluating the instrumentation for like 10 or 12 different parameters: temperature, calibration, linearity, and other parameters that can affect measurements. Because of our quality and precision was on par with NIST, basically the calibration primary, that we would calibrate the instrumentation for the manufacturers of the instrument. And then they would propagate the calibrations to their oven manufacturer customers.

We also provided accurate and precise calibrated instrumentations for the FDA compliance and field staff that were enforcing the oven standard. This was done, so there was no argument about the staff’s leakage measurements. The oven manufacturers were measuring with their own instruments on the production and quality assurance.

So we developed a system for the oven makers that we tested ourselves for assuring daily calibrations of instruments, monthly calibrations of instruments, and local calibration standards which we worked with the manufacturers of the instrumentation to develop. The oven makers also wanted to speed up their production, ao they came up with these robotic systems, some of these were called scanners, that had multiple probes moving along the oven door and other surfaces “scanning” at the same time instead of one person taking about two minutes to do one oven. The manual method is not very fast when you have productions of tens of thousands of ovens per day.

That kind of slows things down obviously. So they wanted to speed that up. We were developing and looking at research. I did some research with another gentleman, Dr. Dan Schubert, who was with us for a short while. We looked at simulations and calculations about how capable are the scanning measurements and can these assure that you’re going to actually see the maximum leakage Would you miss it?

And it turned out, yes, you could miss it very badly. This could result in producing and passing the oven when in fact it should not have passed. And it turned that a key was how far these probes are apart, and how fast they moved. Too far or too fast and you could easily miss the peak leakage. Part of the standard includes how fast the instruments can react.

One of my first efforts with Bill Herman was to correct a technical flaw in the standard technique for measuring the oven leakage. And that took a year or more to finally get that correction into the standard [laugh] because of all of the process it had to go through. But the standard became technically proper because using the terms that they were using originally really didn’t have much meaning.

The flaw was related to the capture area in the antenna and what’s coming out the other end as these can be two different things. You can capture with certain antennas certain things. But is that actually correlated directly with what you’re reading, which is a voltage on a meter? And it turned out that there was problems with real correlation for that particular description.

So we had to develop a technical description that was much more accurate what was supposed to be measuring and how they were measuring it, and relating this to the safety issue that we needed to relate to. I would work with others to develop specific numbers for compliance with the standard based on my instrument evaluations that said, “This is what you use for your production. We know the uncertainties. We mapped those out. We know the uncertainties, and how they’re put together and for individual instruments, and how they work, and this is what you need to use. You can set it at that or lower. But you shouldn’t set it higher.”

We couldn’t tell them they had to. But if they wanted to make sure they met the standard and sell the products, they had to. Bill discovered, with some basic initial work by an engineer at GE who was producing ovens, that one of the make of instruments actually was more sensitive from the back than it was from the front, because the way the antenna elements were put together.

We did some work on that, confirmed that, and then talked with the instrument manufacturer who was a relatively small manufacturer but a major one in that area. They redesigned the sensing antenna part of the instrument and that issue was minimized. So with the redesign, the majority of the sensitivity was from the front.

Lasers were also becoming more widely used so laser safety became a major issue. It’s still an issue because it’s so widely used. Our division and later office still work with materials and mechanical areas for medical devices. We also were engaged in work involving the biology of human exposure to microwaves and there was research and that helped develop a basis for revising exposure limits Howard was involved directly with—Roger was as well—with developing a parameter that helps determine the dose what the actual dose is at the surface and inside tissue.

The University of Washington was one of the leaders. And they developed a parameter called Specific Absorption Rate (SAR) that’s used to this day, and is also used for MRI exposure. It relates the amount of energy deposited using certain constants related to the exposure electric field.

And that was developed based on another development some years before in the ‘60s for what was called the bioheat equation, which I looked at the original report on that was pages and pages of data. Back then, you had to develop it and write it, and it was like 10 pages of just numbers that were used to develop this equation, which also is related to the Specific Absorption Rate about how much energy would it take to be deposited in the tissue to get a certain amount of temperature rise. Electrical characteristics of the tissue with frequency, the amount of energy, are related to how much energy can be deposited, and how much that might heat the tissue. In working with Dr. Kantor and others, we developed phantom configurations that we could expose, and we used references for different materials for different tissues.

Bone tissue, skin tissue, muscle tissue, brain tissue, all of these are electrically different. We developed phantoms that would simulate the arms, the head, the torso. These were all non-dynamic, so blood flow was not part of that. That’s extremely difficult to do. Blood is used in the body to help regulate temperature in the body. The flow of blood also dissipates as heat. But it turns out that for about a minute or less, you ramp up this temperature in the phantom, and it’s almost a linear type of ramp. And from there, you can get the rise—the rate of change of temperature, and use that to help calculate the actual deposition of temperature in this equation.

And what happens is it starts to sort of (now they talk about flattening the curve) does that sort of thing. It starts to become a less of a curve. And in some cases depending if the energy isn’t rising it might actually go down a bit. But it’s never going to go to zero as long as the microwave energy is exposing the tissue.

So that equation, and development of the SAR, and development of standards for exposure that we were working with. We also had a researcher —oh, I feel like I’m just talking and talking and talking here. [laugh]

Zierler:

No, this is great. Please.

Witters:

We also had a visiting researcher Dr. Patrick Reilly that worked with other researchers.

Zierler:

[laugh]

Witters:

We were working with him as he was developing experiments and data about other effects such as RF exposure and nerve stimulation. And it turns out that, and this also applies for other things like MRI and other things, that not only is heat the basic mechanism by which tissues are affected by RF, but it turns out that nerve stimulation, direct nerve stimulation by this energy, this electric field that’s actually getting into the body, has effects. And these can be quantified.

So there are two major exposure standards—no, I can’t say standards; one is a standard, and one’s a guideline—that are used to develop and guide for RF exposures to keep them below certain thresholds. The first one is the IEEE; that’s the Institute of Electrical and Electronics Engineers, the biggest organization of scientific professional, engineers in the world. It’s worldwide, but based primarily in the US. Howard was the convener or chair of one of the IEEE standards committees that developed the dosimetry techniques and standard for measuring these non-ionizing fields that is used in the measurement standard for exposure. The IEEE exposure standard is graded by the exposure frequency, because it differs by frequency on how it interacts with the body. It’s graded by the exposure and the time.

And the Specific Absorption Rate or SAR is related to that by time and exposure. However, SAR is not necessarily the best quantification, but it’s one of the most straightforward and it’s accepted across a lot of areas. It’s hard to say that a certain number for Specific Absorption Rate is the end-all be-all. But in reality, it’s used that way now. [laugh]

The temperature rise in a certain time period is related to SAR. The stimulation of the nervous system, which is everywhere in your body, is the second major qualification of exposure safety. The International Committee on Non-ionizing Radiation Protection , which is international, that again Howard was part of, and others developed guidelines back in the late ‘80s, ‘90s, I believe, published these based on some of the work that was done in our lab, to establish thresholds for exposure, again graded by frequency. But looking at the nerve stimulation as the basis, not the heating.

Zierler:

Now, Don, as these thresholds are developed, are you working with medical doctors? I mean, who’s the authority on determining, you know, what are healthy levels of exposure? I mean, who needs to be involved in this besides your office, or not? Is it all self-contained in terms of making these determinations?

Witters:

No, this is international. There’s an organization called the Bio-electromagnetics Society, made up of scientists, engineers, biologists, some MDs that do research and get together and help assess the research papers and publications. I in many cases, the same people working on the guidelines and standards. The IEEE C95 standard for human exposure has over 100 reference citations of research that go back many years.

When I was working with Bill, he volunteered to do a thorough review and critique of a book that came out in the ‘90s I think it was by Paul Brodeur, who had been a writer for The New York Times, as I recall, and wrote a series of articles about the issues involving primarily of radar installation that the military was doing up in New England. This was a more powerful radar that was being developed to be able to sensor targets over the horizon, and going to be located in an area—where was it?—near Cape Cod Massachusetts or somewhere in New England. Depending on the frequencies and how you do it, radar can do that. Instead of just being a point-to-point, which is primarily what it is used for, they can at the lower frequencies see over the horizon.

They were developing a technique using multiple antenna arrays, multiple antennas in an array, a large array, at certain lower frequencies. And people living nearby were just starting to get nervous about that. They heard about the problem or issues, and Paul Broduer wrote the series of articles which he put into a book, and Bill reviewed that book. (* "The Zapping of America: Microwaves, Their Deadly Risk, and the Coverup" – 1977)

Bill went back and looked at some of the original research which went back to the 1930s. In the 1950s the Military was the primary driver of that, and they called it Tri-Service. The Air Force, the Navy, the Army were involved in this, looking at those exposures because they were all using radar. And some of the research from some of those reports were really significant. Radar operators in the early days—are you familiar with what was called the DEW Line?

Zierler:

No.

Witters:

DEW, Distance Early Warning, this was at the height of the Cold War. They were putting a line of radar systems up primarily on the Arctic Circle. The idea was to see the missiles coming over the Arctic because it’s a lot shorter distance to the Soviet Union.

They were operating these radars, fairly powerful radars. They didn’t have the over the horizon. But, in effect, it could do that. And some of these operators, it wasn’t unusual for them to look down in the tubes where kilowatts generating, and they were looking to see if it was operating. And they could tell if the antenna elements at the bottom of these waveguides were red because they were heating up.

Now that’s a massive dose right in the eyes. Radio operators—this is just one of those anecdotal things that we heard about. Another was some of the World War II and beyond facilities like submarines [laugh]—this was just one of those funny stories—would get their—get a little bit of extra money by talking some of their shipmates that were going on leave to—they’d tell them, “Oh, I’ll expose you to my radar, and it’ll make you sterile temporarily.”

And there’s a reason that that could be true. It turned out that one of the effects of some of these exposures, and particularly down in the male areas, could in fact change the sperm generation, and affect it. And it also turned out that some of the research that Bill was looking at and uncovering showed that there was a propensity for the radar and radio operators to have female children instead of what might be male, in a proportion that was different from the general population. So there were a lot of these kinds of things that were going into some of the research they were doing.

And the book by Paul Broduer turned out to be pretty well on the mark. He wasn’t a scientist, and never claimed to be a scientist, but he was using very good research and resources. And he really did a good job researching.

And by looking at that, you can get an idea of where concerns and research came about, and why they started setting these limits the way that they were doing. And, can see how the concerns were leveraged for things like microwave ovens which were becoming a big product that people bought in their home. Other than that, nowadays, before computers, radio systems like Wi-Fi and Bluetooth, that probably would be the biggest potential source of radio frequency exposure that you might have in your home. Since 1971 microwave ovens are under the standard I mentioned earlier and this product is probably the most rigorously controlled of any product you bring in your house. FCC has some controls, but mostly because the ovens work in their unlicensed band. The oven makers still have to register and comply with FDA regulations.

Zierler:

You mentioned there were some other products besides microwaves where there were issues where, you know, you had to—I don’t know what the right term is—cease and desist or where you wouldn’t let them sell in the marketplace. What were those other items? I don’t think you mentioned them specifically.

Witters:

Well, you can think of anything that’s producing a signal that’s radiating or that’s producing electromagnetic field. Now, way back when, I don’t know if you’ve seen this but X-rays were being built into systems that you could go into a shoe store, and put your foot under the X-ray, and they could size your shoe. And that was just one radiation product out there.

Zierler:

[laugh] I bet you get a really good measurement, if anything else. [laugh]

Witters:

Well, no, you get a really uncontrolled X-ray exposure. [laugh]

Zierler:

Right. [laugh]

Witters:

And it really wasn’t controlled. That was another driver for the Radiation Control Act. They took the show X-ray products off the market though I don’t know when. But in the ‘40s or ‘50s, you know, new gadgets and things were like they are today, making a lot of sort of buzz. And that one was one that was again another driver to get up to Radiation Control Act and beyond. Yeah, there’s a lot of things.

We also—I started working and led a project of research on the effects of cell phones on implantable cardiac pacemakers. Early on, cell phones were in fact basically the same as a handheld walkie-talkie type radio. It was one channel was established for one conversation, which is pretty inefficient but that’s—that was based on radio technology, and the type of computer systems, and algorithms that they were using at that time.

The original cell phones were really developed back in the early ‘70s, and really didn’t start to make much penetration until the ‘90s. Well, in the mid-’90s, there were some reports that we picked up on with cell phones affecting pacemakers. And it was clear the scheme that they were using to send and receive these signals was within the band pass, within the capture of sensitivity, of pacemakers.

Pacemakers are what are called bradycardia devices. They’re used and implanted as a mitigation for heart conditions where the heart is not able to pace itself properly. It’s in some cases—bradycardia means it’s slow, slower than it should be, or they’re missing a lot of beats. The heart is this four-chambered little mechanism that the left side is the major pumper of your oxygenated blood. The right side is coming from the lungs.

The left side is pumping out the oxygenated blood that came from the lungs into the heart, and is pumping it out. So you get your oxygen in the blood in the artery system, the higher pressure system, and then it’s returned in the venous system. After it gets to the extremities, the cells have got their oxygen, it comes back relatively deoxygenated up into the right, into the lungs, and then into the left, and pumped out into the body.

It’s a beautifully marvelous, elegant little system that we all evolved with. And it’s worked well, and works hopefully well into the future. The pacing of the heart is really controlled at a sinoatrial node that’s in the upper portion of the left atrium Do you know a little bit about the heart?

Zierler:

Yeah.

Witters:

OK. So it turns out that about 10% of the people who have serious enough conditions who are using implanted pacemakers, are totally dependent on that pacemaker because they’ve lost that ability within the heart to do it itself. The early cell phones were more powerful than what’s used today. Although today they can still ramp up the power, but they don’t do it because ramping up the power means you drain the battery quicker.

And the systems they use now are very much more efficient than they were then. But it turns out that some of the signals that they were using with the analogs were within the capture of the pacemaker. The pacemaker is sensing the heart rate, and automatically deciding, “Do I pace or not?” These are called demand-type pacemakers. They only output a stimulation signal to the heart when they need it, on demand.

They can be set up in a number of ways by the cardiac surgeons and the cardiologists, and programmed in a number of ways. And that’s evolved over many years. The pacemaker sensors were capturing and sensing the signal from the cell phone as if it was coming from the heart. They couldn’t distinguish. And that way, they were basically potentially causing issues with the patients who depend on these devices.

Zierler:

What kinds of issues would manifest? What would you be seeing?

Witters:

They would pace improperly. Now the pacemakers are pretty sophisticated, and more sophisticated as time goes on. And other designs have been developed that the pacemaker now can sort of distinguish some of these interference signals.

But they couldn’t back then, so they were sensing whatever it was that they were sensing, the RF electrical energy from the cell phones, rather than the heart. And in some cases the pacemaker might not produce the needed cardiac stimulation.

From what we could see in the lab several of the pacemakers were affected by the cell phone signals. That the pacemaker would sense the phone signal instead of heart rate and say, “No, I don’t need to output to the heart,” a decision within the device. We worked with the pacemaker manufacturers and the cell phone makers. I was a PI on this project that worked with the manufacturers of the pacemakers. And there’s only really a handful of them because they’re such a sophisticated and such a specialized medical device.

We were able to work with them, get samples from the cell phone companies, and test them in our lab to see what effects were produced. We were able to work with the manufacturers of the pacemaker and manufacturer of the pacemaker filters and cell phone maker. We also were involved with FCC because the manufacturers of phones didn’t want to have the soundbite say, “Your cell phone might do something to my grandmother,” type of thing.

Zierler:

Right. [laugh]

Witters:

So they (the cell phone makers) were quick to help develop solutions and likely they were quick to understand the magnitude of the issues and what could happen. FCC understood when we explained it to them. The manufacturers of the pacemakers understood immediately. And the manufacturers of the pacemakers started changing some of their designs to try to filter out as much of the interfering signals as possible.

The cell phones operate with much, much higher signal carrier frequencies than any can be sensed by the body or by the pacemakers. The working hypothesis based on earlier research and literature indicated the interference to the pacemaker was not directly from the carrier frequency rather the mechanism was through the modulation on the carrier (i.e., the cell signals turning on and off with time and amplitude) that can start to mimic the electrical pacing rhythm signals from the heart. During normal heart function the electrical signals from the heart that are the result of excitable cardiac tissue polarization and depolarizations are sensed by the pacemaker similar to the electrocardiogram (ECG).

The normal cardiac cycle has usually quick depolarizations and, then you have a repolarization with tends to be slower back to neutral type of situation where the cycle begins again. This happens about once a second for the heart. Tissue excitement happens different ways for different muscles, like the muscles in your arms and your fingers that are not in the constant cycle like the heart.

But in the heart, which is an autonomous system, is linked to the brain but it’s still an autonomous system. Otherwise, your heart wouldn’t beat without you saying, “I want it beat.” There’s a lot of autonomous functions linked to your brain that include your heart, lungs, internal organs and other sensing organs. In the case of the interference issues if the outside signals start to mimic the cardiac tissue electrical signals then the pacemaker sensing functions can have problems distinguishing the cardiac signals from outside signals. Particularly the large depolarization, which is what was happening from the outside, it looks to some of the pacemakers that they’re trying to sense like the heart rate.

So the on and off signals which happen in the emissions by the cell phones might just happen to be in the same sort of rate and general waveform that the pacemakers are programmed to sense. The pacemaker’s sensing has to be within a certain rate physiologically, otherwise it doesn’t work. And the physiological signal characteristics are not that broad really, but it is broad enough to pick up a signals from outside the body that we use all the time.

When we did this research, and we sat down with the pacemaker manufacturers, they wanted to do it quickly. And , the manufacturers of the cell phones said, “What can we do?” And they didn’t want to reduce the phone power output. But the manufacturers of the pacemakers obviously were worried about patient safety. The patients’ safety was primary for us as well.

The FCC was and is primarily concerned about the people who are making the cell phones, and how they’re used and tested. But we helped them because the FCC isn’t a public health agency. They count on us for that part. We work with them closely to assure that what they’re allowing in terms of signals being transmitted are not going to grossly cause problems with the medical devices.

So we worked with the manufacturers. The pacemaker manufacturers quickly understood what the problem was. We came up with a test procedure relatively quickly and the method was designed to be straightforward and easy for trained staff. We discussed various approaches and the The manufacturers of the phones agreed to label their phones to say, “Keep them at least 6 inches from your body, at least from the area where these may be implanted.” So the pacemakers are down here (typically in the upper chest area near the heart), your cell phone is typically up here (typically close to the ear), that’s more than 6 inches, 15 centimeters.

Pacemakers are usually up here (upper portion of the chest) under a flap of skin, and they put the pacemaker generator, which is about that big (about 2 to 3 inches across), and some are even smaller about the size of the end of your thumb. and they put them here, and then the leads are led into the heart through the cardiac surgeon. And the end of the lead is typically the stimulation surface part. The generator outputs a little voltage that via the lead stimulates the heart to beat in with the programmed pacemaker signal. So we worked with the manufacturers.

The problem was the signal getting into the pacemaker systems from the outside. The pacers have filtering to filter out as much of the outside noise as much as possible. They pacemaker manufacturers redesigned the filters to do that. But that’s not a quick and easy thing. They’ve had 50-plus years, 60-plus years of working in the interference problem. So they have very good filters.

There’s a company that we worked with that was really good at this, understood, and they made the filters for the manufacturers of the pacemakers, and improved those dramatically. So that now the outside signals, even though they pick it up the leads can act an antenna, , it’s metal inside your body, a relatively big antenna. The filters filter the outside signals before it can possibly get inside the generator can, and it won’t get into the circuitry. So the filter is right there at the generator input.

And remember, a pacemaker is a totally sealed system. It’s a metal can, typically titanium, that’s totally sealed so that all the fluids and things can’t get in there. And also it’s filtered so these electrical signals can’t get in there. So we worked with the manufacturers. They improved their product.

And in a short order, with the 6-inch separation, both by the manufacturers of the cell phones and by the pacemaker manufacturers, and the fact that the pacemaker improved their filtering, plus the fact that the cell phone startedat that point were going to digital system. Now the digital cell phone systems, instead of having one conversation for one person at one time, they have multiple conversations on the same frequency line at the same time. They break it up into multiple pieces which is going so fast, we don’t notice it—you and I don’t notice it right now—that again is the cell signal modulated.

But the modulation of certain cell systems is—there’s dozens of different kinds of systems that was big in Europe and now is pretty much in the US called GSM- has what they call polling that sends a signal to the cellular base station to stay in touch. And what that does is you want to be able to have a phone call come to you at your cell phone.

Zierler:

Sure.

Witters:

How does a cell phone system know where you are and where your phone is, and is able to direct that call to you pretty much instantly? They have to send a signal called polling back to the base station wherever that is. If you’re walking down the street, that’s changing as you go. And that polling turned out to be again within the band pass of these kind of medical devices.

So, we had a handle on the interference issue pretty much settled for the analog phones, which were dying off anyway. And here comes the digital, and here comes this polling that again is in the pacer band pass. We had to do research with the manufacturers. We had—a cardiac surgeon actually was part of that team that we were working with of researchers, and we were working on the cell phones -- And then it turned out that other things were exposing people to signals that might interfere with the devices You know the anti-theft systems in your stores?

Zierler:

Sure.

Witters:

So the metal detectors that you probably go through?

Zierler:

Yeah.

Witters:

OK. Those are electromagnetic sources. The anti-theft systems in stores, it turned out one of them that was very popular—there’s only a handful of companies that make those—was again having a modulation signal that could be picked up by pacemakers and other implanted devices.

Now, if you’re going to the airport—we work with FAA later they became part of DHS. There’s a research center in Atlantic City for the FAA, and we worked with them directly on looking at metal detectors. And we were doing testing with anti-theft systems because we wanted to make sure about all of these things that people walk through. And they wanted to know how can we assure the public, the traveling public, that these security systems are not going to cause them any kind of issues.

Zierler:

This is people with and without pacemakers? This is the whole—the entire public you’re talking about?

Witters:

Well, we were primarily concerned with the ones with medical devices that were implants. Pacemakers are the largest group of that. There’s somewhere in the order of a million plus around in the US, and in the world probably times that, because it’s been on the market. It’s been so widely used.

It’s done such good with patients who live many years longer than they would without it. Then along just—I’ll tell you. Along in the ‘80s and through the ‘90s, started to develop implanted cardiac defibrillators. Now defibrillator is a device that’s meant to treat tachycardia. The heart is going too fast.

When you get—the heart is a magnificent little elegant tool that pumps the way it pumps. The ventricles, the atrial, they’re all aligned with each other. And normally it operates beautifully. However, if there are some issues, some pathologies or some damage or something that throws that off, that mechanism and its timing, you can have it slowing down, like we were talking about with pacemakers. You can have it going fast.

I’m not a cardiac surgeon. I’m not a cardiologist. But I’ve learned this from looking at these devices, and how they can be affected by these sources that are around us. The tachycardia can lead to—if it’s beating too fast, that can lead to fibrillation when the heart is just sitting there like that. It’s not really pumping, and that can very quickly lead to death.

You see in the movies and TVs where they, you know, turn on the defibrillator, the external defibrillator, wait for something, say “clear,” put it on, hit the body with this massive amount of energy. That’s a lot of energy going through the body because you have to have that to go through all these tissues, and depolarize the heart pretty much as one if you can.

What happens is you depolarize the tissue in the heart, the muscle tissue, the excitable stimulation tissue, and the heart comes back by itself. It’s not starting the heart. It’s basically putting it into a neutral type of situation, and then it comes back by itself, if it’s going to come back.

Now, this has been incorporated into a defibrillator implant that you can put in the body. The initial ones were about this big, about the size of a pack of cigarettes. The ones now are smaller, about that big (2 inches (5cm) across) and do the same job. They evolved from electrodes that were on the outside of the heart to stimulate a lot of the muscle to something that essentially is like a pacemaker with leads in the heart in certain areas.

And with this large energy release, the heart is in this tachycardia fibrillation then you’re depolarizing the whole heart. And most of the time with these patients, it starts to get back into its regular rhythm. So the defibrillators also have e same kind of interference issue. Also, several of the implantable cardioverter/defibrillators, also know as ICDs now have pacing functions, so it’s all-in-one. They can do both jobs.

Zierler:

Don, when you started to look at cell phones, I understand that pacemakers was the trigger issue there, but what about looking at cell phones as a problem in and of themselves like microwaves in terms of exposure? Were you ever involved in those kinds of studies?

Witters:

I was not involved in that, but our folks like Howard and others were involved in it. Because in order to be able to quantify what’s happening, you have to have a measurement of the dose. You have to understand that, and look at how that is.

So some of the—I did a little bit of work with hand radios, the kind that the police and the guards use, which are much more powerful. Several years ago we did some research dosimetry work with I think it was the Duke University, looking at if you hold the radio like this, where the antenna’s right above your—right in front of your eye, how much is coming into the eye. And it turns out that was pretty significant.

We did work with police radars, measuring the exposure from police radar. And we also did a few experiments with the type of radar they use for measuring baseball speed. We did work on measuring [laugh]—we actually had some cars that they came over from the Secret Service because they put a lot more powerful radios, and they hide them a little bit in the cars. And it turned out they were putting them (the antennas) in the back behind the back seat.

So the person in the back seat was potentially getting a pretty healthy dose under that window in the back, you know, that little deck. Some of the radios we were measuring were used by police and fire departments because, depending on where they are in the frequencies, if you’re a state police officer, you may be out in the hills area, so you need a more powerful radio to get your signals out. The fire engines and fire radios—I just want to touch on some of these other things.

You mentioned about the exposure. Yes, we were doing that work. I wasn’t directly involved in that, so I really don’t want to speak to that too much. But we—because of our 20 to 30 years prior to that with looking at this for things like microwave ovens, and other radio sources, and developing—help develop the Specific Absorption Rate or SAR, this quantification. With this metric we could now quantify aspects of the emissions and exposure were based on that.

And FCC started incorporating some of the techniques we had developed for measuring this. Others had developed this too. It’s not FDA doing this alone. We’re part of a larger group, but we have that expertise and the instrumentation.

They started using robotics positioning arms, which we have one in our lab, to measure and map out the exposure from the cell phones, which is a standard technique. This technique includes simulating the head with a phantom, which is basically a saline-type solution and includes with a phone underneath and using a small instrument to measure the exposure in what would be the head, say. That’s the standard technique we helped develop. And working with the FCC in helping to hat the FCC has set a limit.

So all manufacturers of the cell phones, they have to meet those limits, and they have to say what they are in their literature. One area that I did want to talk about is electromagnetic compatibility. In medical devices which are—Bureau of Radiological Health merged with Medical Device Bureau in the early ‘80s. And the act that gave FDA authority over all medical devices was the Safe Medical Device Act of 1976.

It took several years for them to organize that because of the wide range of medical devices. And because medical devices were around long before 1976, a lot of them got grandfathered in even though we hadn’t established baselines for safety and effectiveness, which are the key issues. Nowadays, we stretch the range of all medical devices from scissors and the mask, the gloves that are used.

The COVID has been just a very hectic time to get out enough information so that people using those in healthcare systems and others are able to use them. And we’ve tried to—under some of these emergency acts which, to my experience, had never been really implemented. But it’s in the law that we can do that under these kinds of conditions to aid a quicker and more responsive way of getting the equipment, the medical devices, that they need as quickly as possible, and allowing them to do some procedures that are less than we might typically allow.

But we’ve looked into that with our experience, and work with these organizations to do that. But my area primarily is electromagnetic compatibility. And the big thing that you’ve heard about ventilators.

Zierler:

Yeah.

Witters:

You’ve heard ventilator, ventilator, ventilator.

Zierler:

Sure.

Witters:

Ventilators are a very special, very precise type of medical device that’s been developed over many years. People going on to ventilators is not a minor thing. They can’t breathe on their own, and this is involving a tube that has to be very carefully put into their throat into their lungs, not into their stomach or anywhere else.

And it’s not something that can be done easily, not—you can’t just do it. You have to have experience and knowledge, and know it right. People going on ventilators very, very serious, because a ventilator is essentially providing air in, and helping it get at the rate that the Doctor prescribes and they’re set up to.

If that’s disturbed, because these people are on this for weeks, you can have major, major problems. If it stops for any period of time, that person may not survive. These are electric and electronic devices. All electronics, like I was mentioning with the pacemakers, can be disturbed by these radio signals.

So electromagnetic compatibility means it’s compatible with what the expected environment is. And in hospitals, it’s expected to be controlled, especially in the intensive care units where those kinds of devices are used. What I was talking about with the cell phones and the pacemakers, that’s electromagnetic compatibility. It’s compatible. It’s immune or not susceptible to a level that they test to.

That level can be exceeded if you bring the radio closer. But we try to make sure to mitigate that as much as possible. And electromagnetic compatibility or EMC includes the emissions from the electrically powered medical device. Certain devices like X-rays and MRI have a tremendous amount of electromagnetic radiation that they have can emit if not properly designed, constructed, installed and maintained.

Anything that is electrically powered has an electric and magnetic field that it emits all the time that it’s on. Our concern is that ventilator might be affected by somebody bringing in, oh, a cell phone or a guard radio or something. Electrical medical devices can also be affected electrostatic electricity especially considering you and I and any other person carry potentially 10,000 volts or more of electrostatic energy on our bodies under certain conditions. You don’t feel the electrostatic typically because it’s a surface phenomenon. But it’s there, especially when it’s dry. And in the winter when you go to touch the doorknob or touch your car, what happens?

Zierler:

A little zap.

Witters:

Right, and the color of that little spark, and how far away it actually occurs gives you an idea of how much energy you have stored on your body. So the farther it is and the bluer it is, the higher you have sitting on your body, and you don’t feel it, until it’s discharged. That’s called electrostatic discharge or ESD.

Electronics are extremely sensitive to that. Manufacturers or electronics and medical devices and microwave ovens, and anything else that’s got electronics, go to great lengths to minimize the electrostatic. All the people working with the PC boards, for example, when they’re manufactured wear little wrist things to ground themselves, and they have to ground themselves connected to the metal table that they’re working on so that that’s all shunted to ground and not to the electronics.

Electronics—electrostatic can destroy electronics. It can destroy the electronic components or possibly alter software and these days this is so complicated that unfortunately a lot of software, tens of thousands to millions of lines, some of that’s never really tested thoroughly. And the old or untested routines might stays in there.

This is one way the hackers get in. Many hacks are via older routines or technology that nobody’s bothered to change. And they figure out a way to get there and take advantage of that. So getting back to the ventilators, if you have that kind of phenomenon, that interference, it could cause it to stop. It could cause it to change its rate. It could cause a number of problems.

Zierler:

Have you seen evidence that this has actually happened with the coronavirus crisis, all those ventilators in use?

Witters:

I have not heard of any of that. But the reports and the reporting mechanism and the things that are going on make it really difficult to get any of that kind of information. Remember that the people in the healthcare system are not trained in this area. Their priority is the healthcare and medicine. If they see these phenomena, and it leads to serious injury and death, they are required by FDA law to report that. But the reporting mechanism of feedback, especially in times like these, can be inconsistent and slow.

Zierler:

But if you did see these kinds of reports, you wouldn’t be surprised because these things actually can happen?

Witters:

Yes. Now there’s another source that is widely used in healthcare, and it’s used in commercial stuff a lot too. They use systems called RFID, Radio Frequency Identification. It’s been around for a long time.

A simple form of that are the anti-theft systems on your clothes—a very simple form of that. You walk through it. The signal’s set up inside of these gates. And it hits the tag, and then sends back a signal that says, “Boom, I’m going out there, boom, alarm.”

They use it, and they use RFID now with sensors on it. They can track the temperature, the humidity, all number of things that they can track while it’s going in the shipping. So if you’re shipping a drug that’s temperature-sensitive, you want to get it somewhere, you might use a tracker like that to track how it’s gone through, and what the temperature is.

But even if they don’t do that, even if it’s just simple, they’re tracking pallets of things going out with one system. These systems operate guess where? The same system in many cases operates within the band pass of what the medical devices can sense, and they can have problems.

They’re used widely to track drugs in hospitals, medical devices. In fact, most of the inventory for pacemakers, because they are so expensive and so specialized, are tracked using RFID, and they’re very tightly controlled. And there are regulations that they have to abide by that. It’s used for tracking patients in some cases.

It’s used for tracking clinicians, nurses, other people, and equipment of course. You want to know because in a large system, you may have 100,000 pieces of equipment. Where is that ventilator? Where is that infusion pump when I need it? There it is. They also have to track the supply. Sometimes they’ll use it for that.

Sometimes if a patient, say, needed blood, they might use it to track the blood to make sure because you give a person the wrong blood, they’re in trouble pretty quick. So electromagnetic compatibility is where I’ve been specialized for the last several years, developing and helping to develop standards, helping to perform research. We had a—wow, I can’t believe I’ve been blabbing for so long.

Zierler:

Oh, not at all.

Witters:

The FAA and then the DHS and also the TSA we’ve worked with them. And the last project we did, large project—you know the body scanners that you see?

Zierler:

Yeah.

Witters:

We tested two generations, one generation, the first generation, and then they came back and we did more EMC work with the second generation because TSA and DHS recognizes FDA as the experts in this area. In fact, the medical device manufacturers wanted to work directly with DHS, and they said, “No, you need to go through FDA because they’re the ones that we’re going to go through.”

We have the expertise with the medical devices. We have the expertise in this area developed over many years, and they come to us, which I and others are very proud that we have that reputation with other agencies. We tested both the first and the second generation of those body scanners with—the last time we did it with 54 different medical devices which we worked with the medical device manufacturers who were very interested in this, several manufacturers of the pacemakers and neurostimulators working with us.

Plus, in the last several years, one of the biggest growth areas is diabetic patients. They have to test their blood in some cases multiple times a day. We worked with them, and I have helped review some of those products over the years. And they’ve incorporated now Bluetooth and other systems. And the thing that is more of a concern when we were doing the body scanners are the insulin pumps. Are you familiar with those?

Zierler:

Yeah, I’ve heard about insulin pumps.

Witters:

OK. The insulin pumps themselves, again about the size of a pack of cigarettes, have a reservoir of insulin in them, and it’s programmed to release that through a catheter that sits usually in the lower abdomen of the belly over a period of time. And it’s—I’ve been told by the clinicians that if it’s done properly, it’s much better than the person injecting themselves because it tends to be much more even.

It’s programmed so their blood glucose levels are much more even instead of the up when they have their insulin injection, and then over the day it kind of goes down, and then up again, and that kind of thing. The insulin pump can keep it at a certain level because it will sense. I also worked on the team to review the new closed loop systems, which we approved just a year or two ago, that are both sensing and feeding this information back to the pump and then the pump is deciding, preprogrammed to that patient, when they inject more of a bolus of the insulin.

So it’s now a closed loop. So the systems that are sensing the blood glucose, talking directly to the pump, talking to blood glucose monitors which the patient still does in many cases, and this whole system is working together to keep that level of insulin relatively steady. The population, as I understand it, of potential diabetics that could benefit from them is in the millions, unfortunately.

So the implanted part of those devices—you probably are not going to take those off if you have to go through the airport. And, you can’t take out a pacemaker. You can’t take out these other devices. And some you can’t take out. So we were testing those to see did they react to this? None of them did, which is good.

The manufacturers of the medical devices because of us rigorously working on and reviewing for EMC and making sure about this per national and international standards and testing the medical devices now are very good at protecting for EMC. That’s not to say it’s perfect. But they’re very good.

We still see a few hundred or more reports, and thousands really, of interference issues or things that we believe are interference every year. And depending on certain things, certain new technologies like the pumps and others, you—we do see it in occasionally spikes. But we’re able to deal with that with the manufacturers on a pretty rapid basis.

But, still, we see these reports. It’s not gone away, unfortunately. But I think that’s better reporting, more reporting, and recognition of these issues by the people and clinicians, and an improved reporting network, we’re able to get that.

Zierler:

Well, Don, I think I have two final questions that are—one is sort of retrospective, and one is sort of forward-looking. And on the retrospective one, I mean, this has been great. I’ve been—you’ve taken me on a tour of all of these devices, and how all of these processes work. And, I mean, it’s really remarkable to listen how all of this comes together. And I wonder if in all of these stories or devices that you’ve worked on, is there any one in particular that stands out as being most satisfying to you in terms of, you know, coming across a problem, forging a solution, and really seeing it be implemented, and actually producing positive results?

Witters:

Yeah. I didn’t mention the work we did with wheelchairs, powered wheelchairs.

Zierler:

Oh, OK.

Witters:

And the pacemakers was really satisfying because I think everybody did that. I didn’t mention the issues that we had with the wireless medical monitoring systems that we had to work with very quickly the FCC and the TV broadcasters. Because prior to that, these systems were relegated pretty much to very small areas that were vacant TV channels and some radio services, and that changed with digital TV and there were some issues very quickly. The first one that got—the first television broadcast that was really testing down in Texas knocked out a unit of intermediate care monitoring in a hospital.

Zierler:

Wow.

Witters:

Fortunately, and we—I know a few people down there. They were really good. They got the proper type of equipment, a spectrum analyzer, and they saw there’s a big signal there. It was coming from the TV. That wasn’t there yesterday.

They figured it out very quickly. They called up the broadcaster, and said, “You’re causing us major problems. Patients are not being monitored because of these signals.” It wasn’t because the TV station weren’t allowed. The FCC had allowed them. It wasn’t because the hospitals weren’t allowed. They were allowed.

It was because the FCC did not give these monitoring systems separate—or allowed them to go to places that would avoid that problem without just changing over. They just hadn’t thought about that unfortunately. We had actually told them a year or two before that that this was a problem that they needed to address.

It turned out also in working on this that there were some significant changes at FCC. People retired. The TV broadcasters really got on that one very quickly because they knew that in one sentence, they were in trouble. “My hospital is being knocked out by General Hospital, the soap opera.” See how that come across?

Zierler:

Yeah. [laugh]

Witters:

They recognized that one too. They got on FCC, we got together with FCC, and within a year—unfortunately it took a while because hospitals cannot move that quickly. Hospitals aren’t radio people.

But FCC’s used to working in like six-month time frames, and that just didn’t work for most hospitals and clinics. We worked with people at Walter Reed. This one gentleman, Joe McClain (since retired) was very interested with and got connected with the American Society of Health Care Engineers, which is part of the American Hospital Association Joe organized a national survey to assess what wireless telemetry was out there and who’s got what.

And it turns out there’s something like 8,000 or 9,000 hospitals all over the country. And about half of them were using the previously vacant TV channels, and half were using these other radio services, and all of them were vulnerable to this, and it happened in more than one place. We were able to work with them and sit down—and a very thoughtful person at FCC became the new head of the Office of Engineering and Technology. We worked through the AHA on getting radio specter for medical devices and the FCC created the Wireless Medical Telemetry Service (WMTS) specifically for this.

And I was really, really proud of the way we worked with them, the way we were able to get to the solution including the AMA sitting at the table, the hospital associates sitting at the table, the manufacturers at the table, the FCC at the table, we at the table, and we worked this out. And it came into being, and it’s still there.

Most of the instrumentation in medical devices has evolved to where they basically just use chips for Bluetooth and Wi-Fi. It’s cheaper and quicker. But that in itself has problems. But I was really proud that we were able to work together for the WMTS that we were involved in before it happened, trying to resolve before it happened.

Zierler:

So, Don, I think for my last question, I want to ask forward-looking, what do you see as the future? What does the future hold for electromagnetic compatibility? What are new technologies coming online, and how might you anticipate them, and how might you mitigate some of these concerns that might be coming down the pipe?

Witters:

Well, the biggest one coming down the pipe is 5G, which despite everything you might’ve heard is not really totally implemented yet. There are pieces of it that certain carriers have done. But it still hasn’t completely worked out the rules.

And the technology is in some cases, yes, it’s deployed, and it’s meant to be very much more reliable, very much more capabilities in terms of carrying signals. How that will implement in medical devices, at least immediately, looks like telemedicine, perhaps telesurgery, which some countries have already done.

I read about one in India where an operation a year or two ago using telemedicine and remote surgery, where there was a robot on the other end, and he was some distance away, and the surgeon was working with it. I’ve heard something more recently about that for brain surgery; really precision stuff. That plus imaging will be a lot more reliable. They call it ultrareliable.

But there’s also the issue that we have helped develop over the years which is called wireless coexistence. So if you have your Wi-Fi and your Bluetooth, they don’t always work together very well. If you have them going at the same time, especially if you have numbers of them going at the same time in a smaller are, it could cause problems, slowdowns, perhaps even knock one of them off, because of the way they work.

So we’ve helped develop a standard for measuring that. We’ve helped develop—I chaired a committee of the Association for the Advancement of Medical Instrumentation (AAMI) on a document to assess the risk, and develop a methodology to test, if it’s needed, and use an IEEE standard we also helped develop to do testing . So wireless coexistence is not only for medical devices, but that’s our drive. It’s for anything. Will it coexist?

And with the 5G, which is going to use a much wider range of allocated radio spectrum that’s much, much wider than it’s ever been before, going up into very high frequencies, that we’ve actually used—because the body scanner uses one of those frequencies. It’s 26 gigahertz; very high. That can’t be sensed by the body, but it has its own limitations. It doesn’t go through materials very well.

Lower frequencies do that much better, but the higher frequencies don’t. The systems require massive—what they call massive antenna arrays that are in the size of like that. It’s very small, but there’s hundreds of antennas in there. And it’s dynamic. So as you’re walking along, it’s able to calculate through its algorithms, and give you the best signal as you’re moving.

And all these signals are bouncing around, and it can tell and figure out the best one. So bandwidth can carry steady video and the video wouldn’t freeze (like you did earlier). If you can imagine in the middle of a surgery, if it freezes, uh-oh.

Zierler:

Uh-oh. [laugh]

Witters:

And also a big thing about that is, in the medical arena, training, they can train people remotely. Not only treat people but train the physicians and the clinicians, nurses remotely, and much more reliably on that. We’re kind of taxing the internet system right now. As you can see, the things are freezing up a little bit. We’re taxing that pretty much with the technology we have.

The 5G is promising to make that seamless and almost instant. So 5G is one of the biggest things in wireless. And from my experience, medical devices—any medical device that has an electronic circuit, they look at. And a lot of them incorporate wireless because the chips are cheap, and the chips can do multiple things.

So now your medical devices may not just be Bluetooth or Wi-Fi, which are short-range, but they also have cellular. I personally have to have a CPAP that helps with my nighttime breathing and helps with other conditions. The cardiac and even the eyes can be affected if you have that problem and you don’t take care of it. The CPAP has a cellular connection in it.

Zierler:

Amazing, amazing.

Witters:

I found it my case the information about the cellular connection well, it’s in the manual but it’s a little hard in some cases to find that. But, yeah, and the reason for that is you don’t know what you’re going to have. You couldn’t count on a Wi-Fi connection in a house.

So the cellular allows them to monitor if they want to, and they do, what the patient is going through, particularly are they complying. And that’s another thing that wireless has brought to it. We work on pills that actually have a small chip in them that can be digested through the body.

The pill is swallowed, and it can be monitored through the system. This is not the same as the pill camera, which is used to diagnose. That they swallow a camera, and they can actually see—it’s not quite a video but it amounts to a video—as it goes through the system. And then they can see where these issues are that may not be picked up well on MRI or a CT. I did want to mention something because I started talking about things [laugh] so quickly, sorry. [laugh]

I’ve been there for a while, and I’m just, you know, really enthusiastic about what we’ve done, and how it’s helped people. I was really lucky early on. The FDA was very much into allowing workers to go back to school, and funding them.

And there was a small program at Georgetown University downtown here that was being led by Dr. Robert Ledley. Now he I remember; very impressive. I mean, this guy in my mind was a genius.

He was heading a program down in the basement of I guess it was the dental school, with a handful of researchers. And he was able to do that because he had developed a few years before that the first whole-body CT system. He was originally with the National Bureau of Standards —before it was NIST, it was National Bureau of Standards.

And he worked actually with one of the first electronic computers. This goes back into the ‘40s and ‘50s. And he was writing programs and algorithms to recognize patterns. So he could recognize the patterns for genetic material.

And one of his early medical related projects looked at the way that they used to do amniocentesis for genetic materials was they basically stuck a big needle in through the umbilical cord, in through the mother’s belly button, to get amniotic fluid, and withdraw it. It had blood in it as well. And then they would centrifuge that to do what they called licing - to open up the cells and break out the genetic material. Then they would open up the cells, put them on plates, look at the microscope, and then pick out the genetic material.

But they had to match them because we have 23 pairs of genetic materials (46 chromosomes) that control what we are and who we are. He was able to work out the chromosome pairing via pattern recognition with punch cards based computer systems to recognize the outline of that tissue, and recognize the difference between the different chromosomes.

This was before he developed the whole-body CT system, which is in the Smithsonian. He developed a Back Projection Algorithm for creating the CT image so that it is—that he could create 2 and 3 dimension type of images of inside the body from the 2D image slices of the body.

Now that system was developed originally, CT, by Dr. Hounsfield, who got a Nobel Prize. But it was limited because what Hounsfield did, you had to have the body in water. And you couldn’t do that with people. You can’t put their body and their head in water.

Dr. Ledley’s really genius was to create this back reconstruction, so you didn’t have to do that. He went through, as we went through this program—it was a master’s program for Georgetown—and he showed us his first X-ray which is all beat up. But here’s this orange sitting in the air, and you could see every dimple and every seed and everything in that orange.

He developed that. It became what we now call CT. It was so, so great to be in his program, and do it. And it turned out that one of the researchers that was in that program went over to FCC when we were starting with the cell phones. And in meeting with the Commissioner of FDA and FCC, I met him again. [laugh] It was like wow.

He actually was the scientific advisor for the FCC Commissioner. And I was scientific advisor for this particular issue to the FDA Commissioner meeting. That was one of those sort of, you know, things that just happened. [laugh]

Zierler:

Now, was that a degree-granting program, or this was—what was your affiliation at Georgetown?

Witters:

It was a master’s program. So I got a master’s degree at that program, a two-year program.

Zierler:

And what was the program in?

Witters:

Biomedical engineering or medical engineering. It was a great program because it was a series of lectures by people working in the field. The one that I remember the best was a neurosurgeon who had an electrical engineering degree as an undergraduate, and he started his lectures by talking about the body as a system. I knew right away I was going to like this lecture.

Zierler:

Yeah, I mean, you’ve referenced systems many times yourself in our discussion today. It’s really—

Witters:

This was just fantastic, fantastic. So it really was I thought more than just a regular classroom-type experience. These were the people who were doing this stuff. These were the people who were doing it.

The class on hemodynamics, the guy who was teaching it, there was no in-press book he found. He found a book that had gone out of print, and he would copy the pages. And then he told us he was sending the money that we would pay him—just a small amount—to the guys who originally wrote it. [laugh] But that was a great experience.

He even allowed us—Dr. Ledley told us—you could go into the hospital and see these things, and talk to these people. So I went into the MR system, which was really interesting in talking to the techs and the doctors, and seeing what this was, and how it was going. Really connecting with what was going. It was great. Anyway.

Zierler:

Well, Don, I want to thank you for our time today. This has been tremendously fascinating, and it’s a really special opportunity to get a real inside look at what—you know, how physics is employed at FDA, and all of the very tangible ways that your work has, you know, helped people in real life situations. So it’s been really great talking to you, and I really appreciate your time.

Witters:

Well, if you ever get a chance, you’re in the neighborhood, you could come in and see our lab when we open up.

Zierler:

That’s right.

Witters:

We have probably the largest single lab in that whole FDA White Oak facility because the chamber that we need to do this work though it is not a big chamber compared to the Military type chambers, but it is a significant portion of the laboratory. We have a lot of things we’re doing.

Zierler:

Well, one more thing to look forward to. [laugh]

Witters:

Let me give you a tour of that facility. My group is—I’m just one piece of that group. I have been privileged and honored to work with my mentors and people who came in afterwards. Dr. Victor Krauthamer among the distinguished staff as a research neurophysiologist.

He came in, and essentially created from nothing a neurophysiology and cardiology program that now we have several researchers working on. And that’s just the area immediately. He became our division director as well. He retired, ah, what’s it, two or three years ago.

But he really expanded a program that just meshed perfectly with what we were doing in the electromagnetic area, working with stimulation and what it takes and what are the thresholds? Are they more than they need to be? And it turns out in some cases they are. How do you see that, especially visualizing it, because visualizing actual nerve stimulation, and the signals going to the nerve is really a science in itself.

Zierler:

Yeah, that’s great.