Do cell phones and wi-fi systems cause brain tumors?

Not a day goes by where I don't see someone talking on their cell phone in Belltown and downtown. Most of us own a cell phone and use it daily. Sorry to cause concern, but reports are coming in that using a cell phone dramatically increases our chance of getting a brain tumor. In this month's GQ magazine, there's an article called Warning: Your Cell Phone May Be Hazardous to Your Health. The author of the article, Christopher Ketcham, compiled data from research and personal interviews and reported:

Interphone researchers reported in 2008 that after a decade of cell-phone use, the chance of getting a brain tumor--specifically on the side of the head where you use the phone--goes up as much as 40 percent for adults.

And

. . . an independent study in Sweden last year concluded that people who started using a cell phone before the age of 20 were five times as likely to develop a brain tumor.

The article is a 5-page internet article and is easy to read most of the time, and at other times it gets very in-depth with the technological information. I encourage you to read it and determine whether the claims in the article are true. Until then, here are some excerpts.
According to this article, brain tumors are not the only hazard linked to cell phone use.

Though the scientific debate is heated and far from resolved, there are multiple reports, mostly out of Europe's premier research institutions, of cell-phone and PDA use being linked to "brain aging," brain damage, early-onset Alz¬heimer's, senility, DNA damage, and even sperm die-offs (many men, after all, keep their cell phones in their pants pockets or attached at the hip).

What is so harmful about a cell phone?

The only honest way to think of our cell phones is that they are tiny, low-power microwave ovens, without walls, that we hold against the sides of our heads.

His article doesn't stop with the hazards of cell phone use. Wi-fi systems are all over the place, coffee shops, shopping malls, book stores, and our homes. In my building, my laptop can "see" at least 20 wi-fi networks that belong to my neighbors. Some of the names assigned to the wi-fi networks are humorous; one network name invites ladies to come to his unit and another one tells of his/her hatred for the New York Yankees.
Wi-fi is everywhere in Belltown, downtown, and your town; here's the hazards caused by them.

"It never ceases to surprise me that people will fight a cell tower going up in their neighborhoods," Blake Levitt, author of Electromagnetic Fields: A Consumer's Guide to the Issues and How to Protect Ourselves, told me. "They they'll install a Wi-Fi system in their homes. That's like inviting a cell tower indoors."

Wi-Fi operates typically at a frequency of 2.4 gigahertz (the same frequency as microwave ovens) but is embedded with a wider range of modulations than cell phones, because we need it to carry more data.

Other countries are already starting to take action against wi-fi systems.

In April 2008, the national library of France, citing possible "genotoxic effects," announced it would shut down its Wi-Fi system, and the staff of the storied Library of Sainte-Geneviève in Paris followed up with a petition demanding the disconnection of Wi-Fi antennas and their replacement by wired connections. Several European governments are already moving to prohibit Wi-Fi in government buildings and on campuses, and the Austrian Medical Association is lobbying for a ban of all Wi-Fi systems in schools, citing the danger to children's thinner skulls and developing nervous systems.

Like Ketcham, I'm not trying to be a conspiracy theorist. I ran into the article while trying to get some much-needed fashion advice. I could not imagine not using my cell phone anymore, and getting rid of the very convenient wi-fi system in my place. While reading the article using my wi-fi internet connection with my cell phone at my side, I started to get a headache; probably from all the bad news I was reading, but perhaps for the reasons stated in this article.
For now, I'm choosing not to worry about it, but Ketcham concludes his article with the following statement from a retired researcher named Allan Frey:
"Until there are bodies in the streets, I don't think anything is going to change."