If you're allergic to the metals nickel or cobalt, you may want to consider that when you pick a mobile phone.

In a new study, researchers tested new and used mobile phones for nickel and cobalt. Some people are allergic to those metals. The allergies can cause skin redness, swelling, itching, and blistering where the metal touches your skin.

Some of the BlackBerry phones studied had nickel in them. Many of the flip-phones studied had both metals.

None of the iPhones or Androids studied tested positive for either metal, says researcher Luz Fonacier, MD, of Winthrop University Hospital in Mineola, N.Y., and State University of New York Stony Brook.

She says wear and tear may result in more nickel being exposed. "In those phones that looked like the keypad had a lot of wear and tear, they were more likely to test positive for nickel."

"In the BlackBerries, the nickel was found mostly on the keypads,'' she says.

What if you don't want to give up the model you have despite that rash? "If you really love your cell phone, use an earpiece or use a cover," Fonacier says.

"If you are severely allergic, you should consider getting a cell phone with no nickel," she says.

Fonacier will present her findings Monday at the American College of Allergy, Asthma & Immunology annual meeting in Anaheim, Calif.

Cell Phones: A Closer Look

Phone models that had no nickel and no cobalt detected in all phones tested included:

• iPhone 4
• iPhone 4s
• iPhone 3
• Motorola V950 Rugged Flip
• BlackBerry Torch
• BlackBerry Curve
• Motorola Droid

Models that had nickel but no cobalt included:

• BlackBerry Bold
• BlackBerry Tour
• LG Flip VX 6100
• Sony Ericsson Flip Z520a
• Motorola Flip v265

Phone models tested that had both nickel and cobalt included:

• Samsung Flip SCHA670
• LG Flip CV 500
• LG Flip VX 4400
• Motorola Flip E815

Industry Responds

CTIA, The Wireless Association, deferred to scientific experts on the issue of nickel and cobalt content of phones and allergic reactions.

Research In Motion (RIM), which makes BlackBerries, reviewed the study findings. "Research In Motion takes careful steps to design all BlackBerry smartphones with no exposed nickel on the exterior surface," says Krista Seggewiss, a company spokeswoman.

"Nickel, commonly used in electronic parts for soldering and plating, is found inside all smartphones,'' Seggewiss says in a statement.

"However, this only becomes a concern for customers with known nickel allergies when a pure nickel or high nickel content material is exposed on the smartphone's surface that comes into contact with the skin. If a customer has any questions or concerns about whether or not a product is safe for their use, they should consult a licensed medical professional.''

These findings were presented at a medical conference. They should be considered preliminary, as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.

SOURCES: Luz Fornacier, MD, dermatologist; head of allergy, Winthrop University Hospital, Mineola, N.Y.; professor of clinical medicine, State University of New York, Stony Brook.American College of Allergy, Asthma & Immunology 2012 annual scientific meeting, Nov. 8-13, 2012, Anaheim, Calif.Krista Seggewiss, spokeswoman, Research In Motion, Limited.

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