User guide
70 
studies investigated any possible association 
between the use of wireless devices 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 existence of any harmful health 
effects from wireless device RF exposures. However, 
none of the studies can answer questions about 
long-term exposures, since the average period of 
device use in these studies was around three years. 
5. What research is needed to decide whether 
RF exposure from wireless devices poses a 
health risk? 
A combination of laboratory studies and 
epidemiological studies of people actually using 
wireless devices 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 
reliable proof of a cancer promoting effect if one 
exists. Epidemiological studies can provide data that 
is directly applicable to human populations, but 10 or 
more years’ follow-up may be needed to provide 










