Colgate University First Year Seminar 39: Earth Resources

Term papers


Midwest Power Line Expansion & the EMF Debate

Abbie Webb

December, 2000


Midwest Power Line Expansion & the EMF Debate
The Mid-Continent Area Power Pool (MAPP) predicts that by the year 2006, the Midwest will be experiencing an extreme power deficit. This will cause blackouts and brownouts throughout the area, especially during the summer months (North American Reliability Council, 1998). In an attempt to prevent this power crisis, the Northern States Power Company (NSP) has announced plans to construct 35 new transmission lines in Minnesota by the year 2008 (Dangers, 2000).
  Because the new transmission lines will provide the Midwest with a more reliable source of power, most people support the NSP’s proposal. However, the route that the NSP is currently proposing for the expansion goes directly through several communities, in some areas passing less than fifty feet from houses (Dangers, 2000). These communities are fighting the proposal.
The main concern of the angry Minnesota residents is that the new transmission lines could pose health hazards. Several studies have shown that the electromagnetic fields (EMF) associated with high-energy transmission lines might be linked to health problems such as cancer, heart diseases, Alzheimer’s Disease, Lou Gehrig’s Disease, depression, miscarriages, stunted growth, and birth defects (Dangers, 2000). Home owners also worry that the lines will have negative effects on their area aesthetically, leading to decreased property values. They have suggested that the NSP bury the lines, or take a different route through the area, but the NSP has ignored their request, arguing that it would be too expensive, and that there is no proof that EMF is dangerous.

The History of the EMF Debate
  For decades, scientists have known that high-energy power lines are surrounded by electromagnetic fields. However, they believed that the energy emitted was of such a low frequency that it couldn_t have any biological effects. It wasn’t until the 1960’s that people began to suspect that EMF could be harmful. The debate began when studies in the Soviet Union showed that utility workers at high voltage substations had an unusually high occurrence of sleeplessness and headaches (Sagan, 1996). Then in the 1970’s, U.S. ambassador, Walter Stoessel, developed leukemia after working in the U.S. embassy in Moscow. The high-energy surveillance system maintained by the Soviets was blamed for causing his cancer (Sagan, 1996). The EMF issue was brought to the attention of the public by the Wertheimer-Leeper study of 1979, which was the first to suggest that EMF was linked to childhood cancer (Sagan, 1996).  From that point on, many EMF studies were done.  Although the vast majority of these studies found no significant link between EMF and health problems, the few studies that did find a link have been enough to keep scientists wondering if maybe EMF really could be dangerous.

  For years, scientists have believed that the electromagnetic fields associated with power lines had no biological effects, positive or negative. But some recent studies contradict this belief. For example, the migration paths of certain birds that use geomagnetic fields to navigate have been known to be altered by power lines (Avery, 1978). Also, according to a study by James D. Hays and Neil D. Opdyke of the Lamont and Doherty Geological Observatory, an incredibly large number of organisms died during periods in history when the earth_s magnetic fields switched directions (Becker, 1978). Another study, by Rutger Wever of the Max Planck Institute, found that the electromagnetic environment of the atmosphere can affect the circadian rhythms of humans (Becker, 1978). Finally, a scientist by the name of Andrew Bassett found that human bone tissue healed faster when an electrical current was induced at the site of a fracture.  (Becker, 1978). While none of these studies prove that EMF is dangerous for humans, they do suggest that these fields can have biological effects.
  In recent years, some scientists have been able to find links between EMF and health problems in the laboratory. James H. McElhaney of West Virginia University found that low frequency electric fields, like those emitted from power lines, can cause bone tumors in rats (Becker, 1978). Gordon Marsh of the University of Iowa found that even lower frequency fields can affect the growth of flatworms (Becker, 1978). R.O. Becker and A.A. Marino found that after a month of exposure to a 60 hertz electric field, rats exhibited hormonal and biochemical changes similar to those caused by stress. They note that chronic stress can cause a wide variety of health problems. Also, after continuously exposing three generations of rats to this same electric field, Becker and Marino observed high levels of infant mortality and severely stunted growth (Becker, 1978). All of these studies found that EMF can be detrimental to the health of animals in the lab. While this still doesn’t prove that power lines can be harmful to nearby humans, it suggests that it is possible.

Possible Mechanisms
In order to prove that EMF is dangerous, scientists must determine what EMF does at the cellular level to cause the negative effects they have noticed in the laboratory and in epidemiological studies. One theory, the induced-current theory, says that EMF creates electrical charges within our tissues, and this disturbs the cells. However, many scientists argue that the increase in electrical activity associated with exposure to EMF is only a tiny fraction of the amount of electrical activity that takes place in our bodies naturally and is too minute to affect us (Sagan, 1996). This can be seen in Figure 1.


Figure 1: Currents induced in the body by EMF as compared to the body’s naturally occurring currents. (Sagan, 1996)

  Another theory, the transient theory, argues that, although the current that EMF induces in body tissue is relatively small compared to the body’s natural charges, it can still affect the body if the changes in current are sudden. Russel Reiter of the University of Texas has done studies showing that rats exhibit more drastic hormonal changes when exposed to electrical fields that change rapidly rather than gradually (Sagan, 1996). Figure 2 shows the sudden magnetic field changes experienced by an eight year old girl on an average day. According to the transient theory, the abrupt increases and decreases apparent in the graph are the cause of health problems associated with EMF.  The transient theory is being examined more closely, but physicists argue it has some "serious theoretical limitations" (Sagan, 1996).


Figure 2: The magnetic fields experienced by an eight year old girl on an average day (Sagan, 1996).

  A third theory is the resonance theory. This theory suggests that EMF accelerates the movement of ions across cell membranes. Physicist Abraham Liboff of Oakland University in Michigan supports this theory, citing his observation that calcium ions cross cell membranes more quickly when influenced by electric fields. This could have profound effects on the body because calcium ions are important chemical messengers that trigger several cell functions (Sagan, 1996).
  Another possible mechanism has been proposed in one of the most recent EMF studies, entitled "Increased Exposure to Pollutant Aerosols Under High Voltage Power Lines." In this study, Denis Henshaw and his colleagues from the University of Bristol suggest that power lines cause cancer by magnifying the negative effects of exhaust pollution released by cars.  Between 1989 and 1991, several studies found leukemia to be associated with high traffic density, suggesting that exhaust pollution is a carcinogen. In his study, Henshaw measured the deposition of pollutant aerosols on objects below power lines and compared them to objects 100 meters away from the lines. He found that the objects under the lines were covered with nearly twice as many aerosol pollutants. This would enough to cause a measurable increase in instances of cancer near power lines (Henshaw, 1999).

Arguments Against the EMF - Cancer Link
  It is important to remember that, while the studies mentioned above may seem to prove that EMF is linked to health problems, there are still many arguments against this belief. For every study showing a link between EMF and health problems, there are several others that found no such results. Furthermore, as mentioned above, no mechanism has been proven. While some communities near power lines have an unusually high occurrence of cancer and other health problems, other communities near power lines have seen no such trends. It is possible that the high-cancer rate seen in some of the communities near power lines is nothing more than a matter of chance (Sagan, 1996).

EMF Regulations
  It is obvious that this issue will not be resolved for several years, until enough studies are done to explain the trends we have noticed over the years. In the mean time, many feel that it is better to be safe than sorry. This is the stance that has been taken in many European countries. For example, legislation in Norway forbids the construction or expansion of power lines near places of human habitation. Similar restrictions exist in the United Kingdom, Sweden, Spain, and Australia (Sagan, 1996). The Soviet Union has very specific regulations involving electromagnetic fields. There, the occupational exposure standard is 10 microwatts per square centimeter. In the U.S. the occupational exposure standard is 10, 000 microwatts per square centimeter (Becker, 1978).
 One is compelled to ask why European countries are so much stricter than North America when it comes to regulating EMF.  Investigative Journalist Paul Brodeur believes that the big power companies and several U.S. government agencies know that EMF causes cancer and other health problems, but they are suppressing this information in order to protect their business interests (Sagan, 1996). Whether Brodeur’s conspiracy theory is valid or not, there has been more pressure on the U.S. government in recent years to rethink its EMF regulations. In 1998, the National Institute of Environmental Health Sciences warned that the EMF associated with power lines should be regarded as a possible carcinogen (NIEHS, 1998).  In June 1999, the same organization released its "EMF-RAPID" study in which it "suggests that the power industry continue its current practice of siting power lines to reduce exposures." (NIEHS, 1999). The U.S. government is hesitant to pass any drastic legislation until the relationship between EMF and human health problems becomes more clear. In the mean time, it will provide funding for studies that will help to cast more light on the issue.

The Red-Rock Wilson Line
  While the government’s stance on the EMF issue may seem acceptable for those of us who don’t live near high-voltage power lines, for those that do live near these lines, and are exposed to high levels of EMF every day, the issue seems a bit more urgent.  Unless legislation is passed, people will have no way to protect themselves if a power company decides to disregard the NIEHS’ advisory and build in residential areas in order to keep costs down. This is the position in which the people of the Sunfish Lake community have recently found themselves.
  A few years ago, the NSP (Northern States Power Company) decided to run a new transmission line through the area in order to provide more power for the expansion of high-tech industry in Bloomington, MN. The proposed route would pass within 30 meters of approximately ninety houses along the entire stretch of the line. Eighteen of these houses are in the town of Sunfish Lake (Dangers, 2000). Some of these homes are less than 15 meters from the line. This alarms the area’s residents for several reasons. First of all, if the proposed expansion were to occur, they would be the only people in the entire country to live so close to such a high-energy power line. Secondly, the recently published Henshaw study discussed above found that the effects of EMF can be harmful up to 500 meters away from a high-voltage power line. This would mean that more than 100 homes along the Red Rock-Wilson Line would be in danger (Dangers, 2000). The residents are surprised that the power companies would even consider building so close to houses after the National Institute of Health advised them to site their lines as far from residential areas as possible.
  The Sunfish Lake residents have also expressed other concerns. They worry that the lines will hurt the area aesthetically and thereby decrease property value. They feel that the NSP should also take environmental issues into account. In April of 1995, the town of Sunfish Lake hired an independent arborist to take inventory of the trees that lie on the proposed power line’s path. The results found that the area contains an impressive variety of species, including one butternut tree, which is an endangered species in Minnesota (Mussel, 1999).  All of these trees would be cut down during the construction process. The people_s final concern is that the NSP has failed to keep them informed on the issue and in some cases has withheld information from them or even lied to them. Some of the issues that the NSP has been less than honest about are the cost of the project and the possibility of alternative routes (Power Line Task Force, 2000).
  The residents of Sunfish Lake have proposed a few alternatives to the NSP. They have suggested that the line be built along nearby Interstate 494, rather than through their backyards. As can be seen in Figure 3, the two routes are about the same distance.

Figure 3: Map of the Red Rock-Wilson Line as proposed by the NSP (blue) and as suggested by the Residents of Sunfish Lake, Minnesota (Dangers, 2000)


A third alternative would be to bury the lines. This would eliminate the EMF problem as well as the property value issue because the underground lines wouldn’t give off dangerous radiation and they wouldn_t hurt the area aesthetically. However, the NSP wants to keep costs to an absolute minimum and therefore has refused to alter its plans.
  The residents of Sunfish Lake have taken the NSP to court and are currently awaiting the court’s decision. They hope that the NSP will be ordered to use an alternate route or bury the lines. It could be several months before the decision is made.
  The EMF issue is far from being resolved. While there is some evidence that the electromagnetic fields associated with power lines may cause health problems in humans, the vast majority of the evidence says that no such relationship exists. Nonetheless, the small amount of data that does suggest that EMF is dangerous keeps the issue open for debate. Therefore, the U.S. government has advised power companies to avoid building near residential areas.  As of yet, no legislation has been passed to enforce this advice, because the lawmakers want to avoid making any drastic decisions until further study makes the issue more clear. Unfortunately, this leaves many people, including the residents of Sunfish Lake, in potential danger. If further study reveals that power lines are in fact linked to cancer, miscarriages, or other health problems, it may already be too late to help those people who have already been exposed.


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Becker, R.O. and A.A. Marino. "Electromagnetic Pollution." The Sciences. Jan 1978.

Dangers of Transmission Power Lines. 26 April 2000. <> Sunfish Lake Residents Task Force. "Power Line Update Newsletter."  15, Feb 2000.

Henshaw, D.L., P.A. Keitch, J.J. Close, R.J. Wilding, and A.P. Fews. "Increased Exposure to Pollutant Aerosols Under High Voltage Power Lines." International Journal of Radiation Biology. 75 (1999): 1505-1521.

Mussel, James B. Sunfish Lake Tree Inventory. April 1999.

National Institute of Environmental Health Sciences (NIEHS). Assessment   of Health Effects from Exposure to Power-Line Frequency Electric  and Magnetic Fields. U.S. National Institute of Health: Aug 1998.

National Institute of Environmental Health Sciences (NIEHS). EMF-Rapid Report on Health Effects from Exposure to Power-Line Frequency Electric and Magnetic Fields. June 1999.

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Power Line Task Force. Power Line Update Newsletter. Vol. 2, Iss. 2. April 2000.

Sagan, Leonard A. Electric and Magnetic Fields: Invisible Risks? Amsterdam, Netherlands: Gordon & Breach Science Publishers,1996.