While no solid connection between mobile communications devices and human cancer has been established, studies indicating the likelihood of such a link call for a precautionary approach, medical experts testified at the hearing chaired by Democratic Sen. Tom Harkin of Iowa.
Recommendations included using such devices less, keeping them away from the body, and limiting their use by children.
"Children have a configuration of their skull that does allow penetration of cell-phone radiation," noted Dr. John Bucher, associate director of the National Toxicology Program at the National Institutes of Health.
However, Bucher stopped short of declaring a causal link between cell-phone use and human cancer.
Other witnesses before the Senate Labor, Health and Human Services, Education and Related Agencies Subcommittee noted the relatively short history of widespread cell-phone use, dating back only two decades.
Early studies are inconclusive, said Dr. Siegal Sadetzki of Tel Aviv University, but those done on subjects after 10 years of cell-phone use were showing higher incidences of tumors and other problems.
She cited a correlation between the amount of use, the side of the head where the device was held for talking, and incidences of tumors in salivary glands in that area.
"Until definite answers are available, some public health measures - especially for children - should be instituted," Sadetzki said. "It's not whether we should use cell phones, but how we should use them."
None of the participants in the hearing - including Harkin - said they were giving up their cell phones, but all agreed that restricting use and keeping the units away from the body were good ideas.
Dr. Devra Davis - a founding director of the Center for Environmental Oncology at the University of Pittsburgh Cancer Institute - criticized U.S. regulators and researchers for a lack of attention to the issue. She called for updated standards based on new research, and increased funding for more extensive research.
"I am not alarmed - I am concerned, because the world has changed very rapidly and we have a right to know," Davis said.