In all probability, those warnings exist to ward off lawsuits. It's a sort of, "we told you this could happen, but you used it anyway." Yet that does not mean that the suggested adverse affects are actually true.

oldyellr: To pull from that hydro transmission line comparison: if you think those things are dangerous, you better evacuate your own home. The wiring in your home radiates the same stuff as those big towers, only household wiring is much closer to your body and you spend much more time next to household wiring so it should be much more dangerous. Yet people are driven nuts by the large pylons and don't give household wiring a second thought. Maybe it's because the pylons look so ominous ...