Monday, December 1, 2014

Are Electromagnetic Fields a Health Threat?

Nobody knows. Back in the 1980s several studies were done that seemed to show significant health effects from exposure to strong magnetic fields, especially around high-voltage power lines. The most famous was a Swedish study that showed clusters of childhood leukemia around power lines. But then other studies failed to confirm those early findings, and the initial panic faded. Some scientists, though, continue to worry that the cancer threat is real. After all, we know that something about modern life gives us much higher cancer rates than tribal peoples, so it is certainly possible that electromagnetic fields might be part of the problem. It's just that since we are all exposed to electromagnetic fields all the time in our own houses, it is hard to tease out what effect any particular power line or device might be having. (This is also true of chemicals, refined sugar, strange sleeping habits, and all the other causes that have been suggested over the years.) Anyway, the Retro Report has a feature on the great powerline panic of the 80s, if you are curious.


G. Verloren said...

I've always laughed at the fear of the "electromagnetic fields" of powerlines, because we're talking radio waves, which we've been bathing humanity in en masse for a century with no appreciable results. (On top of the not insubstantial amount of natural radio waves the planet receives from the sun and from space.)

Of course, powerlines produce "radiation" of larger wavelengths than typical FM and AM transmission radio waves, but this actually works against the thought of them having any appreciable effect - EM fields tend to interact with objects less the larger their wavelenghts are, with electromagnetic energy at the smallest wavelengths (ultraviolet, x-rays, et cetera) having the strongest interactions and the most potent effects.

Now, given sufficient intensity, any form of electromagnetic energy eventually becomes hazardous - but for most frequencies, the amounts of energy involved in being hazardous are staggering. There's a world of difference between a green wavelength lightbulb and an identical wavelength industrial laser, for example. You just don't get that kind of energy accidentally. With lasers you have to focus the light into a single coherent beam. For ordinary light without any focusing, you'd need to be pumping out many orders of magnitude more power than you'd ever reasonably encounter. The same concepts apply to radio waves - you'd either need to focus them into a coherent beam, or pump them out at literally cosmic levels of power, or both.

kathy said...

In the early 90's I was friends with a lawyer who was responsible for making a recommendation to the state public power commission on the effects of EM radiation. Her conclusion, based on what she could find at the time, was: I'd be happy to live under power lines, but I think I'll stop using my electric blanket.

leif said...

Verloren has it. this is more hokum just like cell phones and brain cancer. until it can be proven that the radiation is ionizing radiation (and, it's not), then the search for carcinogenic perps must fall on other areas of our lives -- close proximity to high-volume roadways, organic pesticides, cleaning agents, triclosan, dietary factors, on and on.