How can you reduce the risk of using a cellphone?

Send more text messages. Use a speaker phone. Don't sleep with your cellphone next to your head.

Those are just a handful of ways to reduce your exposure to cellphone radiation, suggestions that are gaining momentum now that the World Health Organization declared the wireless devices are "possibly carcinogenic to humans."

"It's not good news, because this is a health issue with potentially devastating affects to people," said Bill Allayaud, California director of government affairs for the Environmental Working Group. "We all love our cellphones, but we all - who know about this - use them in a different manner."

It's also best to use a low-radiation phone and a "corded" ear piece instead of a wireless hands-free device, Allayaud said.

A group of cancer experts with the World Health Organization made the announcement Tuesday after reviewing dozens of studies. One study showed an increased risk of developing gliomas, a type of tumor, in cellphone users who talked on the phone for about 30 minutes per day.

The news did not deter Santa Rosa shoppers from waiting in line for smartphones at the AT&T store or perusing crystal-studded cases at the Cellairis booth in Santa Rosa Plaza on Tuesday.

"When people know the danger, they still do it. I mean, people still smoke," said John Paul Scircia, 31, who said he spends about an hour-and-a-half every day talking on his cellphone.

"I feel like cellphones haven't been around long enough for us to know (the risks)," said Lacey Faddler, 21, a recent graduate of Santa Rosa Junior College who works as a waitress at Howard Station Cafe in Occidental. "I don't know what we're going to do if it does cause it. Everyone has cellphones, even 5-year-olds."

Teaching consumers about health risks associated with cellphones is the goal of Senate Bill 932 in the California Legislature. The measure by Sen. Mark Leno, D-San Francisco, would require retailers to post warnings about possible health problems on display materials in stores.

Leno said manufacturers do include warnings in cellphone manuals, but the warnings are buried deep in the book or require a magnifying glass to read.

"The World Health Organization is known as a conservative body, so this determination of possible carcinogenic effects is profound," Leno said. "When it speaks the world listens."

The cellphone industry said the conclusions reached by the International Agency for Research on Cancer, the branch of the World Health Organization that released the statement, was based on "limited evidence."

"IARC conducts numerous reviews and in the past has given the same score to, for example, pickled vegetables and coffee," said John Walls, vice president of public affairs for CTIA-The Wireless Association. "This IARC classification does not mean cellphones cause cancer."

But locals who are concerned about possible health impacts disagreed.

"I believe this is a real game changer," said Sandi Maurer, founder of the EMF Safety Network, a Sebastopol-based group that advocates for environmental safety and education about electromagnetic and radio frequency emissions. "They've always said we need more studies. Well now, they've classified this in the same category as (pesticide) DDT."