Power Lines: How Valid A Health Threat? -- No Conclusive Link Found Between Magnetic Fields And Cancer Incidence

The concern about cellular phones is new, but the issue of the health effect of electricity is almost as old as its discovery.

It was seized upon as an exotic cure in the 19th century, with both doctors and quacks applying currents to the human body. Dr. Roger Macklis, a researcher at Dana-Farber Cancer Institute in Boston, recently wrote a paper arguing this history of quackery discouraged researchers from serious electromagnetic-field research when electricity became commonplace in the 20th century.

The introduction of radar in World War II finally led to studies on the biological impact of the microwaves emitted by radar, which at close range can heat human tissue.

Then, beginning with a 1979 study in Denver, a series of disturbing but frustratingly inconclusive studies have also shown an apparent link between power-line configuration and the incidence of childhood leukemia.

As a result, many television talk shows immediately lumped power lines and cellular phones together, although they occupy different frequencies on the electromagnetic spectrum and are somewhat separate issues.

Cellular phones emit weak microwaves to relay and receive conversations. Power lines produce magnetic fields some fear can initiate or promote cancer.

What is the source of the concern?

-- Since 1979, a number of studies have compared the power-line wiring configuration outside homes with the incidence of childhood leukemia. While some studies (including one in Seattle and several in Britain) have found no correlation, others in Denver, Los Angeles and Sweden have shown an increased risk of the disease with wiring types researchers predicted would produce bigger magnetic fields, ranging from twice to four times as high.

While this is disturbing, it should be kept in perspective. Childhood leukemia is a rare disease that kills about 500 American children a year. Under the worst assumptions, power lines may be contributing to some portion of this. By comparison, the American Cancer Society estimates that in 1993 160,000 lives will be lost to tobacco smoking and 17,000 to cancer caused by excessive drinking.

Moreover, the connection is far from proved. When scientists have turned from the type of power line to the measurement of actual magnetic fields generated by those lines inside houses, the correlation disappears.

Nor do cancer or other biological effects seem to increase with the strength of the field. The statistical effects turn up at some power levels and not others, with no explanation why.

Nor has a convincing mechanism been proposed explaining what the magnetic fields actually do to the body.

Concern is broadening, however. Scott Davis, a researcher at Fred Hutchison Cancer Research Institute in Seattle, just received a $3 million grant to see if magnetic fields or "light at night" influences breast cancer in women. He will study 1,600 women in King and Snohomish counties to see if results in lab rats can be extrapolated to humans.

Researchers have found that both magnetic fields and lights that interrupt the animals' natural sleep cycle interfere with estrogen production and promotes breast cancer.

-- A number of occupational studies, including some by former state Health Department epidemiologist Sam Milham, have found slightly elevated levels of cancer in line workers, some radar operators, ham-radio operators and the like. For example, a 1990 study by researchers at the University of North Carolina concluded that electrical engineers and technicians had a brain cancer risk 2.7 times the general population. The correlation was much weaker for leukemia.

One study of Navy personnel from 1974 to 1984 showed electricians mates were 2.5 times more likely to develop leukemia than other personnel.

But utility executives point out these diseases are also rare, and that utility line workers often enjoy a greater life expectancy on average than the population as a whole.

-- There are a large number of studies on the effect of magnetic fields on laboratory animals, some showing no biological effect and some showing impacts on melatonin production, tumors, the immune system and behavior. Many are at higher levels than humans are exposed to, however, and it remains hotly disputed whether the results are transferrable to humans.

Few studies have been done exposing humans to electromagnetic fields of power-line frequencies. One Midwest study showed the fields accelerating heart rate, but it was comparable to the effect of drinking a cup of coffee. A study at Battelle Pacific Northwest Labs suggested magnetic fields could affect the body's pineal gland, possibly affecting hormone production and the body's response to cancer. Researchers at the California Institute of Technology last year announced finding small crystals of an iron mineral called magnetite in the brain and speculated they could be moved by strong magnetic fields.

Studies have also shown magnetic fields influencing some cell functions, but not in such a way as to threaten human or animal health.

"There is no definite indication that electromagnetic-field exposure does or does not cause adverse health effects," summed up a City of Bellevue environmental-impact statement on the issue prepared by a consultant called Energetics.

Still, critics such as author and New Yorker writer Paul Brodeur complain that society has plunged ahead with widespread cellular-phone use and electric power-line proliferation without fully understanding the risks involved.

They also point out that the former Soviet Union adopted stricter standards than the West has now out of concern of psychological or unobserved biological effects.

Enough disturbing evidence has been assembled to worry electric utilities about lawsuits, costly line changes or delays in project approvals. At the end of this month, Seattle attorney Michael Withey is scheduled to represent the Zuidema family in the first personal-injury lawsuit based on power-line fears, against San Diego Gas & Electric.

Ted and Michelle Zuidema of San Diego are alleging their 4-year-old daughter Mallory contracted a rare form of kidney cancer while in the womb because of the unusually high magnetic fields in their home. While the suit does not ask for specific compensation, Michelle, on the "Faith Daniels" TV talk show, cited estimates in excess of $1 million.

Withey, who is gaining a national reputation for handling such cases, is also handling a lawsuit by Mimi Handlin, widow of electrical worker Bob Pilisuk, against Seattle City Light that is scheduled for trial in September.

And fears about power lines or substations that lower property values could generate more cases, Withey forecast. "I happen to believe property-damage cases could dwarf those for personal injury," he said.

The costs of defending and settling such cases is ultimately borne by you, the electric ratepayer. Electric utilities are already spending $15 million a year on studies of the power-line issue, and the 1992 National Energy Bill calls for $65 million in public and private research over the next five years.

Jerrold Bushberg, director of health physics at the University of California at Davis, said the public needs to think carefully before demanding utilities spend millions - possibly billions - of dollars into rerouting power lines, changing wiring configurations, widening right-of-ways, or moving homes.

"How much money should we put into this compared to other cancer threats?" he asked. "Is this the best way to spend our risk aversion money?" Using such dollars to give free immunizations to all children would save far more lives, he argues.