101This is because the interval between the time of exposure to acancer-causing agent and the time tumors develop - if they do -may be many, many years. The interpretation of epidemiologicalstudies is hampered by difficulties in measuring actual RFexposure during day-to-day use of wireless phones. Manyfactors affect this measurement, such as the angle at which thephone is held, or which model of phone is used.What is FDA doing to find out more about the possiblehealth effects of wireless phone RF?FDA is working with the U.S. National Toxicology Program andwith groups of investigators around the world to ensure that highpriority animal studies are conducted to address importantquestions about the effects of exposure to radio frequencyenergy (RF). FDA has been a leading participant in the WorldHealth Organization international Electromagnetic Fields (EMF)Project since its inception in 1996.An influential result of this work has been the development of adetailed agenda of research needs that has driven theestablishment of new research programs around the world. TheProject has also helped develop a series of public informationdocuments on EMF issues.FDA and Cellular Telecommunications & Internet Association(CTIA) have a formal Cooperative Research and DevelopmentAgreement (CRADA) to do research on wireless phone safety.FDA provides the scientific oversight, obtaining input fromexperts in government, industry, and academic organizations.CTIA-funded research is conducted through contracts toindependent investigators. The initial research will include bothlaboratory studies and studies of wireless phone users. TheCRADA will also include a broad assessment of additionalresearch needs in the context of the latest researchdevelopments around the world.What steps can I take to reduce my exposure to radiofrequency energy from my wireless phone?If there is a risk from these products - and at this point we do notknow that there is - it is probably very small. But if you areconcerned about avoiding even potential risks, you can take afew simple steps to minimize your exposure to radio frequencyenergy (RF).Since time is a key factor in how much exposure a personreceives, reducing the amount of time spent using a wirelessphone will reduce RF exposure.• If you must conduct extended conversations by wireless phone everyday, you could place more distance between your body and the sourceof the RF, since the exposure level drops off dramatically with distance.For example, you could use a headset and carry the wireless phoneaway from your body or use a wireless phone connected to a remoteantenna.