ROANOKE TIMES
Copyright (c) 1996, Roanoke Times
DATE: Friday, November 1, 1996 TAG: 9611010040
SECTION: NATL/INTL PAGE: A4 EDITION: METRO
DATELINE: WASHINGTON
SOURCE: ASSOCIATED PRESS
A panel of scientists who evaluated about 500 studies on the health effects of high voltage power lines found ``no conclusive and consistent evidence'' that electric and magnetic fields cause any human disease.
``Taken altogether, the current body of evidence shows that exposure to [electric and magnetic] fields does not constitute a threat to human health,'' said Dr. Charles F. Stevens, chairman of a National Research Council committee that spent two years studying the issue. ``We have failed to find a hazard.''
Stevens, a professor at Salk Institute and a Howard Hughes Medical Institute neurobiologist, said Thursday that his committee analyzed about 500 studies conducted since 1979 and found nothing to clearly prove that electrical fields are harmful to health.
No conclusive evidence, he said, was found to link electromagnetic fields with cancer, reproductive and developmental abnormalities, learning or behavior.
There are studies that find a ``weak, but statistically significant'' link between high voltage electrical transmission lines and the incidence of a rare childhood leukemia, but Stevens said the committee found that research to be flawed.
The leukemia link, he said, is based on the assumption that homes near transmission lines are immersed in stronger magnetic and electrical energy fields than are homes removed from such power lines. He said researchers used the size of electrical transmission lines as a basis to estimate the strength of magnetic fields in nearby homes.
Later research, said Stevens, has shown that such estimates are not accurate. Electromagnetic fields in homes near power lines are actually lower than was estimated, he said.
As a result, the committee concluded that studies linking the childhood cancer to electrical wiring ``have been inconsistent and contradictory and do not constitute reliable evidence.''
The committee said that the slight increase in childhood leukemia in homes near power lines may be linked to other environmental factors, such as older houses, higher traffic and more pollution.
Stevens said that even laboratory studies with animals and cell cultures have failed to find biological damage caused by electrical fields. Some of these studies used energies thousands of times stronger than the fields found in the average home, he said.
``People have not been able to think of a mechanism by which electromagnetic fields could have an effect,'' Stevens said.
Electromagnetic fields have been a concern since 1979 when researchers linked some childhood leukemias to the proximity of high-voltage power lines.
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