My last column had a few things to say about claims of cancer risk produced by low frequency electromagnetic fields (EMF). The American Physical Society, after surveying numerous epidemiologic studies, concluded that there was no hard evidence supporting fears of living near power lines. However, there remained certain results of laboratory experiments that show effects of EMF on living cells. These investigations by Reba Goodman (Columbia University) and Ann Henderson (Hunter College) concerning the effects of EMFs on the Myc gene, an oncogene associated with the development of many human cancers, had produced the strongest experimental evidence pointing towards a causal relationship between electromagnetic fields and cancer. What they found was that the Myc gene in immature human blood cells had a two- to threefold increase in expressed RNA when the cells were exposed to low level EMF. The only way to verify work of this nature is to repeat the experiments.
A recent issue of Science (29 September, 1995) reports on two papers in the October 1995 issue of the Journal of Radiation Research, describing attempts to replicate the earlier work, with negative results. The new research not only repeated the older work, but improved on the methods of analyzing the data. According to Jeff Saffer, of the Pacific Northwest Laboratories, Goodman and Henderson had failed to include certain controls and calibrations. When these precautions were taken, “There was no observable effect,” Saffer said.
Here we go again. One experiment says yes, another experiment says no. Well, this often happens in science. We won’t know the final result until enough different people repeat the same work. In the meantime, the EMF work begins to show ominous similarity to the cold fusion brouhaha of a few years ago. Great initial excitement, followed by a simmering down of claims as more careful research finds nothing to get excited about.
In the cold fusion case, physicists with experience in fusion work were initially skeptical because they could not imagine any kind of nuclear reaction that would produce the effects claimed. They thought they had a quite complete knowledge of all the nuclear reactions in existence. But, on the off chance that there were obscure reactions lurking about, they could not come right out and say “cold fusion is impossible.” Therefore a great deal of time, effort, and money had to be spent replicating the original experiments.
In the case of EMF and cancer the situation is even more complex. Here we are dealing with living cells, and we don’t know everything that goes on inside them. We really don’t know much about the interaction between 60 Hertz electromagnetic fields and living matter.
My own initial skepticism on the subject was colored by my experience in working with powerful magnetic fields. When I was at the fusion lab in Princeton I worked with a machine called a stellarator, the precursor of the present tokamak. This was a large device about twenty feet long and eight feet high, consisting of a racetrack-shaped vacuum vessel surrounded by magnetic coils encased in blocks of stainless steel. Occasionally when the coils were being tested I would stand on the platform adjacent to the stellarator and watch in wonder as the four-inch steel slabs would slowly bend toward each other when the magnetic field was pulsed. This was a strong field! But standing a few feet away I felt nothing. Therefore I didn’t think magnetic fields had any effect on me.
However, fields from power lines alternate at sixty cycles per second, quite different from the slowly varying field from the stellarator. These alternating magnetic fields are accompanied by electric fields whose strength is not insignificant. However, to calculate the electric field strength inside a living person and to calculate the effect of this field on living cells is a very complex matter. For this reason it would be foolhardy to claim ahead of time that alternating electromagnetic fields do not have an effect on the health of people exposed to them. The subject is not at all like cold fusion. We have no theoretical reasons for saying EMFs are either good or bad for people. The question must be answered with careful experimental tests.
And I’m glad to see that they are being done.
But let us not go out on a limb like a friend of mine who gave a lecture before a local club extolling the benefits of optimism. He was saying that we cannot put limits on future discoveries in biomedical science. He expected new advances in medicine to increase the human life span indefinitely. I objected, saying that if people live forever then the population growth rate will increase even faster than it does now; in a few hundred years there will be one person for every square foot of the earth’s surface. He replied: not to worry, people will learn how to live in the ocean, how to live underground, how to populate the planets. (Sounds like a lot of the science fiction stories I used to read in the 30s.) The obvious answer to that is: suppose the population doubling time is 100 years, and suppose in the year 2500 you ship half the earth’s population off to Mars to free up some living space. By the year 2600 exponential growth has brought you right back where you were.
There’s no answer to the population problem other than zero population growth.