UF researchers find no link between cell phone use and rare facial tumors

July 16, 2003

GAINESVILLE, Fla. — It won’t end the debate about cellular phone safety, but University of Florida researchers have found no connection between cell phone use and the development of rare, noncancerous facial nerve tumors.

The study was the first to assess whether regular cell phone use is associated with a higher risk of intratemporal facial nerve tumor development, said otolaryngologist Dr. Patrick J. Antonelli, a researcher with the Evelyn F. and William L. McKnight Brain Institute of the University of Florida. UF physicians had noted that facial nerve tumors, although rare, were affecting an increasing number of their patients. The nerve, which controls facial expressions, is located behind the eardrum and is first in line to receive cellular phone radiation.

“Certainly this is an indication that the risk to underlying neural tissue because of cell phone radiation is not as severe as perhaps other reported studies might make it seem,” Antonelli said. “It’s too early to say definitively because widespread cellular telephone use has been around for a relatively short time.”

Researchers also would have required additional patients to arrive at a final answer regarding a link between cell phones and facial nerve tumors. No epidemiological data exists regarding facial nerve tumors – a cause of facial paralysis – but Antonelli estimates they occur in fewer than 200 Americans per year.

When doctors noticed an increase in the number of patients with the benign tumors, Antonelli said they decided to investigate.

“A colleague jokingly suggested that cell phones might be responsible,” Antonelli said. “At first we laughed, then I thought it’s actually not so silly because the facial nerve is relatively exposed in the tympanic segment, and we’ve certainly seen a bump in the number of cases of facial nerve tumors. When you have a suspicion that could potentially impact people who use an emerging technology, you look into it.”

Antonelli and his UF colleagues reported in a recent issue of The Laryngoscope, the official journal of the Triological Society, that they observed no relationship between the regular use of cell phones and the risk of intratemporal facial nerve tumors.

“When you place a cell phone by your ear, the antenna delivers a higher dose of radiation to the facial nerve,” Antonelli said. “If the hypothesis is that cell phone radiation will increase tumor risk, whatever is closest to the radiation ought to be at the highest risk. We didn’t see that.”

Cell phones transmit low-powered radio frequencies, emitting energy in the range of 0.2 to 0.6 watts. In comparison, a walkie-talkie may emit 10 watts or more, according to the World Health Organization.

UF researchers conducted a telephone survey of the cell phone habits of 210 patients with ear, nose and throat diseases who had been treated at Shands at UF medical center, including 18 patients with facial nerve tumors and 51 with acoustic neuromas, which also are benign tumors. Patients with facial nerve tumors were diagnosed between July 1, 1995, and July 1, 2000. The remaining patients had problems that were not related to tumors: 72 had sinusitis, and 69 had voice disorders or gastroesophageal reflux disease.

The researchers found that only two patients with facial nerve tumors-11 percent-regularly used hand-held cellular telephones, compared with 22 percent of patients who had acoustic neuromas and 22 percent who did not have tumors.

Antonelli cautions that researchers must study more patients to make a definitive statement about cellular phone use and facial tumors, and that most people have been exposed to cell phone radiation for less than 10 years, an insufficient amount of time to definitively assess its risk.

However, Antonelli’s findings are consistent with other scientific literature that makes no connection between cancer and cell phones, said Joshua Muscat, a senior researcher at the Institute for Cancer Prevention in Valhalla, N.Y.

“I don’t believe there is any reason to limit cell phone use, but it’s a personal decision,” Muscat said. “Certainly there are things people who are concerned can do to take precautions, such as limit the time they spend on cell phones, or to use headsets or ear pieces. But it seems the weight of scientific evidence points toward the safety of cell phones.”

An exception is a study by Swedish scientists at Lund University that documented how cells in the parts of rats’ brains that control sensation, memory and movement died after being exposed to various cell phones at different levels of radiation for two hours.

Given the large amount of users of mobile phones, even small adverse effects on health could have a major public health impact, according to the World Health Organization. As of December 2002, more than 140 million people subscribed to wireless services in the United States, according to the Cellular Telecommunications Industry Association. During the year, cell phone users chatted for more than 600 billion minutes.