NEW YORK - News last week that an arm of the World Health Organization said cellphones might raise the risk of brain cancer has been greeted by Americans mostly with a shrug of the shoulder - one that's pinning a cellphone to the ear.

Google searches for "cancer" and "cellphones" spiked this week. And some people vowed to get headsets to shield themselves from radiation. But most seemed to either dismiss the warning as too vague, or reason that if the most useful device in modern life poses a slight health risk, then so be it.

"I was watching the news about it, and I thought, 'I'm already screwed because I've been talking on the phone for seven years,'" said Genevieve Chamorro, a 31-year-old New Yorker who was shopping for a phone.

John Gottani, a manager at a cellphone store in New York, said he's been selling phones for six years and has never heard anyone ask if they cause cancer. The only things customers really care about, Gottani said, are "if it works, and if it texts."

The International Agency for Research on Cancer reviewed dozens of published studies on cellphones and cancer before classifying cellphones as "possibly carcinogenic" on Tuesday. It's a risk category that includes night-shift work, engine exhaust and coffee.

Studies haven't been able to rule out a link between cellphones and cancer. But experts say that if there is a link, it's unlikely to be strong. Cellphones emit weak radio waves, which, under the conventional understanding of physics, can't wreak the same sort of cellular changes that sunlight and radioactivity can.

A common tip offered to those who want to reduce their exposure to cellphone radiation is to use a headset. Even wireless Bluetooth headsets reduce radiation exposure. Though they emit radio signals of their own, they're much weaker than cellphone signals.

But there seems to be little rush to get Bluetooth headsets. They've been declining in popularity for at least four years, according to research firm Strategy Analytics. It's also found that most headset owners don't intend to replace the one they have when it wears out.

According to Strategy Analytics analyst Chris Schreiner, the main reason is that when you're wearing a Bluetooth headset, you look like a person who's wearing a Bluetooth headset.

"Style has always been a huge issue in terms of Bluetooth headsets," Schreiner said.

On Twitter this week, the most common posts mentioning "headset" and "cancer" have been repeats of a joke from humor site Someecards.com: "I can't decide between being seen wearing a Bluetooth headset or just getting brain cancer."

Cellphones differ in how much radiation they emit. Proposals in a few states would force cellphone stores to display these radiation ratings.

But CTIA-The Wireless Association, the cellphone industry trade group, is fighting these moves. It says there's no evidence the measured ratings have any correlation with risks. And cellphone manufacturers and carriers are showing no sign of breaking ranks with each other to use the ratings to their advantage - for instance, by touting "low-radiation phones."

Spokesman John Walls said CTIA wouldn't fight a manufacturer that wanted to market a "low-radiation phone." But claiming a phone to be safer than any other would cross the line, he said.

"They're all deemed safe by science," Walls said.

Americans on average talk about 700 minutes a month on their cellphones, making them some of the most talkative people in the world, well ahead of Europeans.

In San Francisco, Chuck Luter, 42, said he doesn't plan to change his habits as a result of the radiation warning. When the advertising-shoot prop stylist talks on his Sidekick phone, he usually uses the speakerphone, so it's not close to his head.

And in any case, he texts more than he talks. Besides, he added, there are few alternatives to owning a cellphone.

"What are the other options? To not have one? To try to keep it all in your head? There are so many bad things for you - just add this to the pile."