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that were developed with the advice of FDA and other federal health and safety agencies. When the

phone is located at greater distances from the user, the exposure to RF is drastically lower because

a person’s RF exposure decreases rapidly with increasing distance from the source. The so-called

“cordless phones,” which have a base unit connected to the telephone wiring in a house, typically

operate at far lower power levels, and thus produce RF exposures far below the FCC safety limits.

4. What are the results of the research done already?

The research done thus far has produced conflicting results, and many studies have suffered from

flaws in their research methods. Animal experiments investigating the effects of radiofrequency

energy (RF) exposures characteristic of wireless phones have yielded conflicting results that often

cannot be repeated in other laboratories. A few animal studies, however, have suggested that low

levels of RF could accelerate the development of cancer in laboratory animals.

However, many of the studies that showed increased tumor development used animals that had

been genetically engineered or treated with cancer-causing chemicals so as to be predisposed to

develop cancer in the absence of RF exposure. Other studies exposed the animals to RF for up to 22

hours per day. These conditions are not similar to the conditions under which people use wireless

phones, so we don’t know with certainty what the results of such studies mean for human health.

Three large epidemiology studies have been published since December 2000. Between them, the

studies investigated any possible association between the use of wireless phones and primary brain

cancer, glioma, meningioma, or acoustic neu-roma, tumors of the brain or salivary gland, leukemia,

or other cancers. None of the studies demonstrated the existence of any harmful health effects from

wireless phone RF exposures. However, none of the studies can answer questions about long-term

exposures, since the average period of phone use in these studies was around three years.

5. What research is needed to decide whether RF exposure from wireless phones poses

a health risk?

A combination of laboratory studies and epidemiological studies of people actually using wireless

phones would provide some of the data that are needed. Lifetime animal exposure studies could

be completed in a few years. However, very large numbers of animals would be needed to provide