Environmental Factor, October 2009, National Institute of Environmental Health Sciences
NTP Provides Updates on Cell Phone Studies
By Robin Mackar
On September 14, 2009, toxicologists from the National Toxicology Program (NTP) traveled to Washington to present updates on research supported by NTP and NIEHS related to exposure to radiofrequency energy from the use of cellular telephones. Wireless communication devices are used by more than 270 million Americans, yet there is little known about the potential health effects of long-term exposure to these devices.
In the morning, NTP toxicologist Michael Wyde, Ph.D., presented an overview of the NTP cell phone radiofrequency radiation studies at an "Expert Conference on Cell Phones and Health: Science and Public Policy Questions." The international conference was organized largely by Devra L. Davis, Ph.D., professor of Public Health at the University of Pittsburgh, and supported in part by NIEHS. Chris Portier, Ph.D., associate director at NIEHS, served on the Steering Committee. According to organizers, the goal of the three-day conference was to propose a U.S. research agenda.
Wyde updated the attendees about the three phases of the NTP rodent studies. The three phases of the studies include: (1) a series of pilot studies to establish field strengths that do not excessively raise body temperature; (2) subchronic toxicology studies where rodents are exposed to various non-thermal field strengths for up to two months; and (3) chronic toxicology and carcinogenicity studies where rodents will be exposed for 24 months. Wyde also discussed how the NTP worked with experts from the National Institute of Standards and Technology to design special reverberation chambers for the studies. Cell phone radiation will be administered in 10-minute on/off cycles for up to 20 hours per day. The NTP anticipates the completion and reporting of all phases of the studies by 2014.
In the afternoon, conference participants were invited to attend a U.S. Senate hearing on cell phones and health at the nearby Dirksen Building. NTP Associate Director John Bucher, Ph.D., had the opportunity to represent NIEHS, NTP and the NIH at the hearing. "While the current scientific evidence has not conclusively linked cell phone use with any health problems, we and other scientific organizations evaluating the available studies have concluded that better data are needed to establish any potential health risks from the low-level radiofrequency radiation exposures associated with their use," Bucher said.
Bucher provided an overview of the NTP studies, which he pointed out are designed to clarify any potential hazards, including cancer risk, from exposure to cell phone radiation. He also responded to numerous questions from Senators Tom Harkin and Arlen Specter. Bucher's testimony can be found online. NTP has also prepared a fact sheet on cell phones.
(Robin Mackar is the news director in the NIEHS Office of Communications and Public Liaison and a regular contributor to the Environmental Factor.)