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PRI's Environmental News Magazine

March 19, 1993

Air Date: March 19, 1993

SEGMENTS

Electromagnetic Radiation: Assessing the Threat / Steve Curwood

Living on Earth host Steve Curwood explores the debate over the possible health impacts of electromagnetic fields. A number of studies have linked fields from powerlines, wiring, even appliances to several forms of cancer, but other studies have found no effect. As public concern continues to rise, policy-makers are still unsure of how — or whether — to take action to protect public health. (21:30)

Show Credits and Funders

Show Transcript

HOST: Steve Curwood
NEWSCASTER: Jan Nunley
REPORTERS: Michael Richards, Joe Smith, Pye Chamberlaine

(Theme music intro)

CURWOOD: From National Public Radio, this is Living on Earth.

(Theme music up and under)

CURWOOD: I'm Steve Curwood.

Electromagnetic fields: they're as common as the computer on your desk and the power lines down the street. But some research suggests they can cause cancer, especially among children. And some say it's time for action.

BRODEUR: I'm talking about not thousands, but over the years, tens of thousands of unnecessary, wholly preventable cases of cancer in American children. Children!

CURWOOD: But the research on electromagnetic fields is contradictory, and many public officials are at a loss.

TIERNEY: You don't know if there is a problem and you don't know if there is not a problem or if change, if the costs of change are warranted.

CURWOOD: How dangerous to public health is our electric power system? This week on Living on Earth. Coming up right after the news.

Environmental News

Nunley: I'm Jan Nunley with this week's environmental news.

As part of its new approach to the problems of endangered species, the Interior Department says it will create a biological map of the United States. As Michael Richards reports from Washington, the plan is geared to help end protracted legal battles over endangered species.

RICHARDS: The idea is to find out exactly what's out there, and what the most critical habitats are, so protection plans can be put into place long before species become endangered. It's called an ecosystem approach, and it's thought to head off the economic dislocation and ensuing court battles that typically occur when species become so threatened that business activities like logging suddenly have to be curtailed somewhere. Both environmental and business groups have expressed support for the idea. The biological survey is designed to be a continuing government project, much like the US Geological Survey, which has mapped the land for more than a century. Work on this new national biological map is set to begin in earnest early next month. For Living on Earth, this is Michael Richards in Washington.

NUNLEY: The Clinton Administration appears to be backing away from a campaign promise by Vice President Gore to block operation of an Ohio hazardous waste incinerator. According to the New York Times, the White House will not challenge a court decision allowing the incinerator in East Liverpool, Ohio to go on-line. From member station WCPN in Cleveland, Joe Smith reports.

SMITH: During the Presidential campaign, Al Gore vowed the Waste Technologies Industries incinerator would not operate until there was a complete government investigation. So after twelve years of fighting the plant, WTI opponents felt they finally would have a friend in the White House. But before the Clinton Administration could take office, President Bush granted WTI a limited permit. And after the appellate court ruling, a US Environmental Protection Agency official said the Administration had no choice but to comply. Some legal and environmental observers don't agree. They say President Clinton could have pulled the permit during his first days in office. Opponents say they're not surprised by the news. They point to the fact that while Bill Clinton was governor of Arkansas, he supported the hazardous waste industry. For Living on Earth, I'm Joe Smith in Cleveland.

NUNLEY: California Congressman Henry Waxman says he'll introduce legislation requiring all the nation's schools to test for radon gas, and to disclose any dangerous conditions to parents and teachers. Waxman's proposal follows an EPA report that nearly one- fifth of US school buildings contain dangerous levels of the radioactive gas.

The Clinton Administration will not appeal a landmark court ruling requiring an environmental impact statement for a proposed Antarctic incinerator. Some Federal agencies, including the Departments of State and Defense, opposed the decision. They fear the ruling could ultimately mean all Federal projects overseas must undergo an environmental review, which could compromise foreign policy goals and military activities. The White House maintains that the decision applies only to Antarctica.

This is Living on Earth.

The Navy has agreed to stop using a Washington State wildlife refuge as a target for bombing practice. Defenders of Wildlife had sued the Navy to stop the raids on Sea Lion Rock, off Washington's Olympic Peninsula. It's home to the endangered Steller sea lion, grey whales, and numerous sea birds. The group wants new Federal standards for activities in and around US wildlife refuges.

American soldiers fighting in the Persian Gulf could have been exposed to dangerous levels of radiation from uranium-tipped weapons. That's according to a report by the National Toxics Campaign Fund, which wants Congress to look into possible radiation illness among Gulf War veterans. Pye Chamberlaine reports.

CHAMBERLAINE: The group's chairman, John O'Connor, says the depleted uranium ammo, used because it is much heavier than lead and better at penetrating armor plate, is radioactive. It vaporizes on impact, and he says it can give people who breathe the vapor, as Desert Storm veterans did, as much radiation as . . .

O'CONNOR: 50 chest x-rays an hour, if you were in one position that had just been shelled by these materials. So we know that even though it's called low-level radiation, it is radiation that nonetheless can cause cancer, birth defects, miscarriage and a host of health horrors.

CHAMBERLAINE: The Army is studying reports of damage to American GI's in Desert Storm. Some experts say that health damage attributed to depleted uranium munitions may have come instead from the huge clouds of oil well smoke and soot in the desert war. For Living on Earth, I'm Pye Chamberlaine in Washington.

NUNLEY: Russian environmentalists say the Kamchatka Peninsula, one of the country's last frontiers, is threatened by wildlife poaching, urban pollution and resource extraction. Local Greens are warning against opening the peninsula's large reserves of oil, gold, nickel, lead and sulphur to development. They also say that poachers are decimating the region's brown bears, and that pollution from Kamchatka's only urban center is fouling the landscape.

That's this week's environmental news. I'm Jan Nunley.

Back to top

(Theme music up and under)

Electromagnetic Radiation: Assessing the Threat

CURWOOD: This is Living on Earth. I'm Steve Curwood.

(Sound of power lines, transformers humming)

CURWOOD: Hear it? This humming sound is produced by the force that powers modern industrial society -- electricity.

(Sound up and under)

CURWOOD: But now, it's also the source of one of today's most controversial scientific and public policy debates. Are the magnetic fields, generated by electric powerlines, harmful to humans? Our story begins in Millis, Massachusetts, a small town southwest of Boston.

RAINSFORD: We are very concerned with the health aspects. The more we look into this, the more nervous we become.

CURWOOD: Two high voltage powerlines run alongside the home of David Rainsford and Christine Schneider. The lines, strung on masts that look like they were made from a giant Erector set, run as far as the eye can see toward the horizon. For the past four years the couple has been fighting the plans of a local utility, Boston Edison, to build a new electric substation 265 feet from their home.

RAINSFORD: Everything we've read, and looked at, we understand that nothing has been proven, no ill effects, but everything we read, the evidence continues to mount, with cancer, leukemia, brain cancer -- you know, all these things.

CURWOOD: Rainsford estimates he and Christine Schneider have spent 20 thousand dollars fighting Boston Edison, organizing meetings, passing out fliers and distributing copies of the book Currents of Death . It's the bible for the growing anti-powerline movement, written by Paul Brodeur. A staff writer for the New Yorker, Brodeur has studied and written about the hazardous effects of electromagnetic fields for more than a dozen years. Brodeur is angry, because he believes utilities and the government have known about the hazards of magnetic radiation for 50 years.

BRODEUR: I'm talking about, not thousands, but over the years, tens of thousands of unnecessary, wholly preventable cases of cancer in American children. Children!

CURWOOD: Magnetic fields are all around us. The earth, even our bodies generate them. But there's an important difference between these natural fields and those fields produced when electric current is transmitted over powerlines. The powerful alternating current switches back and forth 60 times a second. Brodeur says this upsets the body's delicate electromagnetic balance.

BRODEUR: Now you've got to understand something about what happens to you when you're standing near a high-voltage or high-current powerline. In the presence of a relatively strong magnetic field, such as can be found in many American homes and schools, every molecule in your brain and body is vibrating back and forth, 60 times a second, to and fro, to the rhythm of the 60-hertz power frequency. And you know, right off the bat, you don't have to be a rocket scientist or a medical doctor to suspect that in the long run, day in and day out, that may not be very good for you. And indeed it isn't.

CURWOOD: Critics charge Brodeur is "electro-phobic". He writes his stories longhand, and doesn't use a computer. But he has an award-winning history of breaking important environmental stories. Brodeur was the first to report on the health hazards of asbestos, and one of the first to write about the shrinking ozone layer. His stories are detailed, written in a dry documentary style, and scrupulously fact-checked.

BRODEUR: I went to the National Cancer Institute. I discovered that leukemia in children in the last 10 or 15 years is up 24%. That brain cancer is up 30%. That in 1991, the National Cancer Institute issued a report in which it cited a mysterious increase in brain cancer in people of all ages in this country -- in adults of all ages. Why should there be this sudden increase in brain cancer and leukemia? Well, one very, very sound, logical reason would be that there's been an enormous expansion in the power distribution network and carried current, and that many more people are being exposed to harmful magnetic fields than were in the past. So I say again: we have a major, major public health problem here.

RAINSFORD: Now this is just basically a map of the high-tension lines, the proposed substation . . .

CURWOOD: On his kitchen table, David Rainsford spreads out a hand-drawn map of the homes on Dean Street in Millis that are clustered around Boston Edison's two powerlines. There are 9 houses in the immediate vicinity, and many unexplained health problems.

RAINSFORD: I'm sorry, one instance of cancer and leukemia, one instance of leukemia, two women who've had miscarriages that live closest to the lines, and their kids have also had childhood speech impediments which they never thought about before, but now that this thing came out, they're wondering if that's related.

CURWOOD: Measurements of the magnetic field at the Rainsford home average about 2 and a half milligauss. A milligauss is the standard used to measure magnetic fields. Those living closest to the powerlines are exposed to levels that are far greater. These are levels some research has indicated may be linked to health problems. Tired of four years of fighting Boston Edison's plan to build the electric substation, David Rainsford and Christine Schneider have negotiated a deal with the utility.

RAINSFORD: We know they're going to build. We don't want to stay here. We don't want to be guinea pigs, we don't want to find out in ten years or fifteen years that we have cancer, and try to relate it to this thing. So we decided to approach them and see if they wanted to buy the property. And they do.

ROTH: Yes, we are looking at the purchase of the property, but this is in keeping with Boston Edison's general practice.

CURWOOD: Fred Roth is district manager for Boston Edison:

ROTH: We're always looking at properties that are immediately adjacent to our facilities to see whether it's in the best interests of the company to get a little extra land around those facilities.
CURWOOD: How dangerous do you think EMF is to public health?
ROTH: Well, the conclusions of the reports are such that there is no known danger at this time.
CURWOOD: Then it's perfectly safe?
ROTH: We believe it is, yeah.
CURWOOD: And if a person in a house were to take a reading with a meter and found, let's say, 3 to 5 milligauss of a magnetic field, that would be perfectly safe, you think?
ROTH: Again, it has not been proven what is safe or unsafe. But those kinds of readings are very typical of what one would find within one's own home while operating appliances, for example.

SCHNEIDER: Edison said the same thing. What about using your hairdryer? What about using your electric curlers?

CURWOOD: Christine Schneider and David Rainsford.

SCHNEIDER: It's something you use five minutes a day.
RAINSFORD: We're not saying that we should go back to the Stone Age, you know, and sit beside the wood fire, which again is dangerous also. No, we're not saying, that, but I mean, everyone has appliances in the house, but you can limit your exposure to them, you know. And again, they don't run 24 hours a day.
SCHNEIDER: We're not saying don't build it here, just because it's our back yard. We're saying don't build it in anybody's back yard, build it away from people. Especially when you don't know the effects, if there is something there.

CURWOOD: Boston Edison has agreed to buy the house and never build another one on the land. District Manager Fred Roth says the utility supports more research on the possible health effects of magnetic fields. But as far as what's known so far, he says it's safe.

ROTH: If a person is concerned about something, it's very serious to that individual. If you're asking me, do I have concerns, no, I don't have any. You see, when people go making a claim like that, the first thing they oughta do, before they get sawed off the limb which is what I'm gonna do with them right now, is go and find out if they know what they're talking about.

CURWOOD: Writer Paul Brodeur says there are over 40 studies linking magnetic fields with brain cancer, leukemia, female and male breast cancer, even suicide. The most dramatic effects have been found in the workplace, among people exposed over long periods of time. Brodeur cites a1990 survey of telephone cable splicers. Their average exposure was 4.3 milligauss, not an unusually high reading. They had a cancer rate 7 times higher than expected.

BRODEUR: Well, let me tell you, 4.3 milligauss has been measured on one whole side of the Montague Elementary School in Santa Clara, California, which was just shut down by its school board and parents last week for this very reason. 4.4-5 milligauss is a level that I've measured in dozens upon dozens of homes in the United States in ten different states which are close to high current and high voltage power lines. 4 point, 4.5 milligauss is a level that my brother David has measured in day-care centers, and will probably show you one today, right down here in Salem, Massachusetts.

(Sound of street, fade under)

D. BRODEUR: You know what I got? 45 milligauss, this is about what I had two years ago.

CURWOOD: David Brodeur, writer Paul Brodeur's brother, runs an electromagnetic monitoring company.

D. BRODEUR: 37, 38 milligauss. The line is right here, 37 milligauss.

CURWOOD: David Brodeur uses a sophisticated Gaussmeter to measure the fields along Derby Street in historic Salem, Massachusetts, the site of the House of Seven Gables settlement, made famous by Nathaniel Hawthorne. Down the block you can see the smokestacks from the Salem Harbor Electric Power Plant. Underneath the street running in front of a daycare center are two high-voltage powerlines. The needle on Brodeur's gaussmeter is pinned.

CURWOOD: I hear children playing. This kind of exposure, is this dangerous for children?
D. BRODEUR: Yeah. Yeah, if it's throughout the structure. And it depends on how many hours a day they're here.
CURWOOD: If you had a child here, would you take your child out of this?
D. BRODEUR: I'd pull my child right out of here. Yes, I would, I would. I definitely would.

CURWOOD: But Massachusetts' cancer registry doesn't show an unusual incidence of cancer in the area. Even if there were a cluster of cancer cases, scientists say it wouldn't mean very much. There are hundreds of such unexplained clusters around the United States. And Chris Patton, a spokesperson for the day-care center, says she hasn't heard of a problem.

PATTON: To tell you the honest truth, we haven't ever thought of it in connection with its being a hazard, or we haven't had any reason to have an alarm raised, or any red flags, but that may be just because we haven't been tuned in to, our consciousness hasn't been raised about it.

TV CLIP, GOOD MORNING AMERICA: Now how would you go about testing your house for EMFs? Well, first call your local electric utility. Many will test customers' homes free of charge . . . (fade under)

CURWOOD: Since the release in 1979 of the first study linking electromagnetic fields with childhood leukemia, the question of EMFs' health effects has been hotly debated among scientists. But it's only in recent months that the intensity of public concern has grown. Nightline, Street Stories, PrimeTime Live -- even The Tonight Show have bombarded the TV airwaves with information about magnetic fields. But while the public is demanding definitive answers, science is asking more questions.

(Sound of AAAS conference crowd)

CURWOOD: At the recent conclave of the American Association for the Advancement of Science, only a few symposia asked a question, rather than suggesting an answer. Among them, "Do power lines cause cancer?" Tom Tenforde, chief scientist for life sciences at the Battelle Pacific Northwest Laboratories, was one of the panelists.

TENFORDE: Well, the issue is not so much whether there are effects, but the issue is what are the threshold field levels for producing such effects.

CURWOOD: For years doctors have used pulsed magnetic fields to heal broken bones that won't mend, and researchers are experimenting with EMFs to cure arthritis. But they don't know how the fields work, or how they can disrupt cells in laboratory experiments. But there's no question that they do.

TENFORDE: At the cell and tissue levels, there are a number of studies which suggest that there are effects on metabolism, for example, synthesis of DNA and the production of specific proteins. And also some, with some cells, there is some evidence for changes in functional properties and growth state.

CURWOOD: While the magnetic effects on tissues and cells is widely accepted, what effect fields from powerlines might have on people is the subject of considerable scientific controversy. Humans are more complex, and the evidence is confounding, in some cases, contradictory. Research into the adverse effects on people is based upon epidemiological studies, surveys of people living and working near high power lines. Four such studies, conducted over the last two decades, link powerlines to a doubling of the rate of leukemia in children. But Dimitrios Trichopolous, professor of epidemiology and cancer prevention at the Harvard School of Public Health, doubts these studies directly connect the childhood disease with magnetic fields.

TRICHOPOLOUS: The evidence indicates that there is no strong effect, that's for sure. But whether there is a small effect, or no effect at all, it's difficult to say at this time. My personal opinion is that there is no effect.

CURWOOD: For decades utilities have dismissed out of hand any claims that EMFs could have a biological effect. They've pointed out that EMFs aren't like microwaves, which can damage tissue by heating it up; that they aren't like powerful x-rays, which can break genes apart; and that the strength of the EMF fields diminishes rapidly over relatively short distances. But recently, there's been a significant change in position by some utilities, from asserting that there is no impact to conceding that the scientific jury is still out. Leonard Segan is senior medical scientist at the utility-funded Electric Power Research Institute:

SEGAN: There seems to be something interesting here. Four studies have shown the association between the proximity to power lines and childhood cancer. I think we have a responsibility to understand why that exists.

CURWOOD: Epidemiologists use indirect measurements to gauge a person's exposure to magnetic fields, calculating a lifetime exposure to EMFs using what's called the "wiring code" method. It's an historical measurement, based on the distance and configuration of wires near a person's home. The technique is a little like archaeology, where artifacts are used to piece together an understanding of the past. Four epidemiological studies, using wiring code estimates, have linked exposures of about 2 milligauss with a doubling of the rate of childhood leukemia. Some scientists have challenged this method. They point to studies using actual spot measurement, rather than estimates, which show no effect from exposure at such levels. But by far the best study to date uses both methods. And it also found a link between magnetic fields and childhood leukemia. Dr. Anders Ahlbom, professor of epidemiology at the prestigious Karolinska Institute in Stockholm, spent five years studying data collected over 3 decades. He surveyed half a million children living near electric transmission lines:

AHLBOM: We found a fairly clear relationship with the childhood leukemia and electromagnetic fields in their homes.

CURWOOD: What makes this study so important is that Swedish scientists used the most detailed exposure assessment ever attempted. Every mile of high current powerline in the nation was surveyed, and 30 years of spot measurements correlated exactly with the indirect "wiring code method". Dr. Ahlbolm.

AHLBOM: The magnitude is basically that for these homes where we estimated 2 milligauss or more of magnetic fields in their homes, we had more than two times the normal incidence rate for childhood leukemia. And we also saw a dose-response relationship such that the higher the magnetic field, the higher the risk of cancer.

CURWOOD: With long term exposure to 3 milligauss, the Swedish researchers found children had a four- fold increase in the expected rate of leukemia. In light of these findings, Sweden is taking action.

AHLBOM: The Swedish government decided very quickly that they would take this seriously, and that they would consider this as proven and until someone comes up with evidence against it, they have enough evidence to start to try to limit exposure to magnetic fields.

CURWOOD: But critics charge the Swedish study has problems. Only 75 cases of childhood cancers were actually found. It's a small number, and researchers did not find a leukemia link with children living in apartments, only those in single family homes. But Louis Slesin, the editor and publisher of Microwave News, a newsletter that follows EMF research, says the latest study goes a long way to resolving lingering doubts connecting childhood leukemia to powerlines.

SLESIN: The bottom line is that the Swedish data do show a link to cancer, especially to children. You can pick any epidemiological study apart and find trouble with it. But the important thing is the big picture, the overall finding, and the Swedish government stands behind that finding. The link is there, and we need to understand it, and do more work to fully understand how to protect people.

CURWOOD: Four years ago the Congressional Office of Technology Assessment issued a report stating there was "a legitimate cause of concern" regarding EMFs. And last year a draft report by the EPA recommended that magnetic radiation be classified as a "probable" carcinogen, a classification that would have put EMFs in the same category as notorious cancer-causing agents like dioxin and PCBs. But Louis Slesin says the White House pressured the EPA, and the final report downgraded the warning from "probable" to "possible." Not long afterwards, Congress appropriated $65 million dollars to investigate electro-magnetic fields, and researchers at the National Institute of Environmental Health Sciences will soon begin a 4-year study to find out if, and how, magnetic radiation affects animals. Meanwhile, the utilities-funded Electric Power Research Institute is continuing its own studies. But not everyone thinks more studies are the answer.

WITHEY: The problem isn't more studies, the problem is the political will to do something about it. That's what the government of Sweden has done. Now, how many more studies do you want to conduct?

CURWOOD: Seattle attorney Michael Withey represents 9 law firms around the country that are reviewing legal cases involving electromagnetic radiation. There are now 5 cases pending in Federal court, and more than a hundred others nationwide, brought by people who claim powerlines have affected their health or devalued their property. Withey believes the number of lawsuits could explode in a few years.

WITHEY: Whether there is a large number of cases depends on what the public utilities do. If they change their conduct, if they warn people adequately and fairly about the many, many studies that have shown an increased cancer risk to children in exposure to power lines, and if they mitigate and reduce the fields, I don't think there is going to be a wave of litigation. If on the other hand they hunker down, they deny there's problems and they don't take steps to mitigate, then you can count on the fact that people will be bringing lawsuits and I think will be winning those lawsuits. The question is, where is the political will to make these changes to protect our children?

CURWOOD: Some states have begun to address the issue. Florida and New York have established magnetic field exposure standards, but they're a hundred times more lenient than the standard the Swedish government is now considering. And the scientific uncertainty surrounding EMFs has posed a policy-making nightmare for public officials. Susan Tierney was the Massachusetts Environmental Secretary, and was vice-chair of the National Electromagnetic Field Research Program, representing consumer groups, environmental regulators and Federal agencies on powerline issues. President Clinton has asked her to join the Energy Department.

TIERNEY: Fundamentally I feel like we're in a situation with EMF where you don't know if there is a problem and you don't know if there is not a problem. And as a policy maker in that situation, I think that puts you in a difficult spot of not even knowing what direction to move in or if change and the costs of change are warranted.

CURWOOD: Given this level of uncertainty, what can, and should, you do to ensure your health and that of your family? Dr. M. Granger Morgan of Pittsburgh's Carnegie-Mellon University has devised a strategy he calls "prudent avoidance."

MORGAN: Prudence is something we exercise all the time in our private lives. I don't know about you, but I eat a little more broccoli and a little less charbroiled meat than I once did, because it's thought that that probably provides a bit of protection against cancer. There's no assurance of that, but it's easy to do and doesn't cost me much, so I do it. The idea of prudent avoidance is that where you can get people out of fields at low cost and with minimal inconvenience, maybe that's a good thing to be doing, while we wait for better scientific answers.

CURWOOD: Morgan says prudent avoidance in the home includes shutting off electric blankets once they've warmed up your bed, and placing electric clocks a few feet, rather than a few inches, from your head. On a larger scale, he says power companies should redesign their new lines to route them away from human populations. Some utilities have already begun to make such changes, at an estimated cost of a billion dollars a year.

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(Music up and under)

CURWOOD: If you have any comments or questions about Living on Earth, you can call our listener line at 617-868-7454. Or you can write to us, at Living on Earth, Box 639, Cambridge, Massachusetts 02238. Transcripts and tapes are available for ten dollars.

Our story about electromagnetic radiation and powerlines was produced by Bruce Gellerman. Peter Thomson produces and edits our show. Deborah Stavro directs. Our coordinating producer is George Homsy. Our production team includes Kim Motylewski, Lucia Small, Chris Page, Reyna Lounsbury, and Colleen Singer Cox. Our engineers are Laurie Azaria and Doug Haslam. Our theme music was composed by Michael Aharon.

Living on Earth is produced by the World Media Foundation, in cooperation with the Public Media Foundation and WBUR, Boston. I'm Steve Curwood, executive producer.

(Theme music up and under funding credits)

 

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