Some Cellular Phone Owners Link Use to Health Problems : Medicine: Research has yet to resolve cellphone safety question. As scientists devise studies, victims of brain tumors and cancer debate blame.

Debbra Wright, a real estate manager for a cellular phone company in Phoenix, used to live by her portable telephone. Now she has a brain tumor and contends the hand-held models she used daily for six years are responsible.

Susan Reynard of St. Petersburg, Fla., died from brain cancer. A judge dismissed a suit blaming the makers of her pocket phone, citing a lack of scientific evidence. But her husband is not convinced. He notes that his wife’s tumor formed on the side where she had held the phone.

From a Hollywood agent deal-making at poolside to a woman stranded alone with car trouble, some 12 million Americans rely on portable cellphones, with more than a half-million new subscribers signing up each month.

At least eight lawsuits blame health problems on cellphones; none of them have come to trial.

“Do you know what it’s like to . . . have your health go away?,” asked Wright, 42, who has undergone multiple surgeries for her benign tumor. “It’s been very hard to have pain 24 hours a day.”

The first suit, filed by Reynard’s husband in 1992, temporarily turned the emerging industry upside down. Users wondered if they were facing a hazard with each call. Cellular stock prices fell.

Manufacturers rushed to proclaim cellulars risk-free, although they were later taken to task by the Food and Drug Administration for saying thousands of studies over 40 years showed the phones safe.

In fact, most of those studies did not directly look at cellphones. And most of the current research to determine if the phones are dangerous is coming from a $25-million trust fund financed by the cellular industry itself.

Unlike car phones with antennae mounted outside the vehicle, hand-held cellulars like those in the Reynard and Wright cases have antennae that sit flush with the head, exposing callers to an electromagnetic field whose long-term effects remain a mystery to scientists.

“We don’t have enough information to say the phones are harmful. At the same time, we really don’t know enough to say they’re not harmful,” says Elizabeth Jacobson, deputy director for science at the FDA’s Center for Devices and Radiological Health. “I think if there is a risk, it’s probably small.”

Dr. Ross Adey of the Loma Linda Veteran Medical Center--who is conducting cellular research funded by Motorola Inc., the world’s largest manufacturer of cellphones--is worried by industrial studies linking other types of microwave exposures to cancer.

“There is some evidence that suggests the need to know more about these fields,” he says, “because, after all, people are going to expose themselves . . . for the rest of their lives.”

Although there is no proof the phones are hazard-free, industry representatives flatly maintain that scientific studies to date show no health risk.

“The FDA and the EPA and the other agencies that are looking at this can’t be very concerned about what they’ve seen so far if they’re not jumping into and funding research,” says Ron Nessen, vice president for public affairs and communications at the Cellular Telephone Industry Assn. and White House press secretary during the Gerald R. Ford Administration.

But an industry watchdog says such remarks ignore preliminary scientific findings.

“The bottom line is, you can’t deny there’s a possible problem,” says Louis Slesin, editor of the newsletter Microwave News. “It may turn out there’s no serious health risk, but the denial has to stop.”

When you make a call on your cellular phone, you’re relying on a form of energy closely related to what cooks food in a microwave oven.

Cellular phones and microwave ovens use the ultrahigh frequency band of radio waves. It’s part of the great electromagnetic spectrum that includes electricity running through power lines, radio signals, radar, infrared light, visible light, ultraviolet light, X-rays and gamma rays.

Some microwaves have the power to make water molecules vibrate, an action that can produce heat at high enough levels. But at the frequencies used in cellulars, it has always been believed the microwave radiation isn’t capable of ionizing or breaking chemical bonds, a process that can lead to mutations and cancer.

Now, scientists are going back and trying to determine just what effects the waves might have on cells and DNA, the human genetic blueprint found within.

Most previous studies have been conducted at 2,450 megahertz, a frequency used by microwave ovens, not at the 837 megahertz frequency of U.S. cellular phones.

Scientists are unsure whether effects observed at one frequency are relevant at another. In addition, most of the work has examined short exposures to radio frequencies at high powers, not the long-term, low-level exposures associated with cellphone use.

George L. Carlo, an epidemiologist, lawyer and chairman of Health and Environmental Sciences Group in Washington, has been hired by the Cellular Telephone Industry Assn. to devise a comprehensive program assessing the risk and possible responses.

Under the Wireless Technology Research program he chairs, national death records will be compared against a roster of 7 million cellular subscribers.

Multiple research teams will analyze a University of Washington duo’s finding of breaks in brain-cell DNA from rats exposed to two hours of microwave oven frequencies, and other scientists will develop computer models to replicate radio frequency exposure and absorption by the human body.

Cardiologists will conduct experiments to understand how holding some digital cellular models near the chest can interfere with cardiac pacemakers, and researchers also will try to estimate exposure doses--taking into account the phone’s power, antenna design, call duration and the distance to the nearest cellular tower.

At the same time, federal epidemiologists at the National Cancer Institute are exploring whether there may be a connection between portable cellphone use and brain tumors.

Though Carlo is handpicked by the industry association, he insists his research program is independent. He cites a peer review board advised by Harvard University’s Center for Risk Analysis and the requirement that researchers submit their work to peer-reviewed journals.

“On the surface, everything looks kosher,” says Jacobson, of the FDA.

With government sources evaporating, she says she hesitates to criticize the industry’s funding of research into the dangers of cellphones.

“I want to be careful,” she says. “This really is an opportunity to get very needed research done. If it’s handled right, I think it will be a tremendous benefit to everybody involved.”

Meanwhile, the FDA has some simple advice for minimizing exposure to radio frequency energy: Limit your cellular calls.