z “Cooperate in providing users of wireless phones with the bestpossible information on possible effects of wireless phone use onhuman health.FDA belongs to an interagency working group of the federal agencies thathave responsibility for different aspects of RF safety to ensure coordinatedefforts at the federal level. The following agencies belong to this workinggroup:z “National Institute for Occupational Safety and Healthz “Environmental Protection Agencyz “Federal Communications Commissionz “Occupational Safety and Health Administrationz “National Telecommunications and Information AdministrationThe National Institutes of Health participates in some interagency workinggroup activities, as well.FDA shares regulatory responsibilities for wireless phones with the FederalCommunications Commission (FCC). All phones that are sold in the UnitedStates must comply with FCC safety guidelines that limit RF exposure.FCC relies on FDA and other health agencies for safety questions aboutwireless phones.FCC also regulates the base stations that the wireless phone networksrely upon. While these base stations operate at higher power than do thewireless phones themselves, the RF exposures that people get from thesebase stations are typically thousands of times lower than those they canget from wireless phones. Base stations are thus not the primary subjectof the safety questions discussed in this document.What are the results of the research done already?The research done thus far has produced conflicting results, and manystudies have suffered from flaws in their research methods. Animalexperiments investigating the effects of radio frequency energy (RF)exposures characteristic of wireless phones have yielded conflictingresults that often cannot be repeated in other laboratories. A few animalstudies, however, have suggested that low levels of RF could acceleratethe development of cancer in laboratory animals. However, many of thestudies that showed increased tumor development used animals that hadbeen genetically engineered or treated with cancer-causing chemicals soas to be pre-disposed to develop cancer in absence of RF exposure. Otherstudies exposed the animals to RF for up to 22 hours per day. Theseconditions are not similar to the conditions under which people usewireless phones, so we don't know with certainty what the results of suchstudies mean for human health.Three large epidemiology studies have been published since December2000. Between them, the studies investigated any possible associationbetween the use of wireless phones and primary brain cancer, glioma,meningioma, or acoustic neuroma, tumors of the brain or salivary gland,leukemia, or other cancers. None of the studies demonstrated the