Moreover, the journalistic source link tried to make shwannomas seem dangerous, but a quick reading about the tumor via google suggests that the vast majority of shwannomas are non-cancerous or benign.
Well, even if shwannomas are a relatively minor health risk, it would be pretty big news if low-level microwave radiation was causing them.
At present -- as far as I know -- there's no credible hypothetical mechanism by which microwave radiation at those levels can affect human biological tissue in that way. So, if it turns out that it is having that effect after all, then scientists have got a very interesting problem to investigate, and it would make for a much stronger argument in favor of restricting cellular technology just in case it had other health effects we're unaware of.
(I specified human here because it's an important difference. People have much thicker skulls and chest cavities than rodents, so we would expect that we'd need significantly higher doses of radiation to induce the same effects that are being studied in rodents.)
