What's New?
•	September Journal
•	September Newsletter
•	Granite Countertops and Radiation - HPS Response and Information Sheet

Upcoming Events
•	IRPA 12 19-24 October 2008
•	HPS Midyear Meeting Recent Advances in Planning and Response to Radiation Emergencies 31 January - 3 February 2009 San Antonio, Texas
•	54th Annual Meeting of the Health Physics Society 12-16 July 2009 Minneapolis, Minnesota

29 August 2008

Answer to Question #2797 Submitted to "Ask the Experts"

Category: Cell Phones

The following question was answered by an expert in the appropriate field:

I am a student at New York University. I am doing a research paper on cell phones and brain cancer. My question is that I know cancer can be caused when our body is exposed to doses of 50 cGy or higher. What does cGy stand for? What doses do cell phones emit?

The term cGy (centigray) is a unit of absorbed dose of ionizing radiation such as x rays or gamma rays. Cell phones do not emit ionizing radiation. They emit nonionizing radiation, namely radiofrequency (RF) energy. Absorption of nonionizing radiation in the body is measured in terms of the specific absorption rate (SAR) in units of watts per kilogram. Both ionizing and nonionizing radiation are forms of electromagnetic energy. The difference is that ionizing radiation has sufficient energy per photon to cause ionization of molecules. Nonionizing radiation does not. It is the ionizing effect of ionizing radiation that has been linked to increased risk of cancer. For more information on cell phones and health check out a Medical College of Wisconsin Web site. For more information on ionizing versus nonionizing radiation check out a University of Michigan Web site. Gary Zeman, ScD, CHP Lawrence Berkeley National Laboratory

Answer posted on 29 July 2003. The information and material posted on this Web site is intended as general reference information only. Specific facts and circumstances may alter the concepts and applications of materials and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice specific to whatever facts and circumstances are presented in any given situation. Answers are correct at the time they are posted on the Web site. Be advised that over time, some requirements could change, new data could be made available, or Internet links could change. For answers that have been posted for several months or longer, please check the current status of the posted information prior to using the responses for specific applications.