In recent decades, the possibility that use of mobile communicating
devices, particularly wireless (mobile and cordless) phones, may
increase brain tumour risk, has been a concern, particularly given the
considerable increase in their use by young people. MOBI-Kids, a
14-country (Australia, Austria, Canada, France, Germany, Greece, India,
Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain)
case-control study, was conducted to evaluate whether wireless phone use
(and particularly resulting exposure to radiofrequency (RF) and
extremely low frequency (ELF) electromagnetic fields (EMF)) increases
risk of brain tumours in young people. Between 2010 and 2015, the study
recruited 899 people with brain tumours aged 10 to 24 years old and
1,910 controls (operated for appendicitis) matched to the cases on date
of diagnosis, study region and age. Participation rates were 72% for
cases and 54% for controls.
The mean ages of cases and controls were 16.5 and 16.6 years,
respectively; 57% were males. The vast majority of study participants
were wireless phones users, even in the youngest age group, and the
study included substantial numbers of long-term (over 10 years) users:
22% overall, 51% in the 20-24-year-olds.
Most tumours were of the neuroepithelial type (NBT; n = 671), mainly
glioma. The odds ratios (OR) of NBT appeared to decrease with increasing
time since start of use of wireless phones, cumulative number of calls
and cumulative call time, particularly in the 15-19 years old age group.
A decreasing trend in ORs was also observed with increasing estimated
cumulative RF specific energy and ELF induced current density at the
location of the tumour.
Further analyses suggest that the large number of ORs below 1 in this
study is unlikely to represent an unknown causal preventive effect of
mobile phone exposure: they can be at least partially explained by
differential recall by proxies and prodromal symptoms affecting phone
use before diagnosis of the cases. We cannot rule out, however, residual
confounding from sources we did not measure.
Overall, our study provides no evidence of a causal association between
wireless phone use and brain tumours in young people. However, the
sources of bias summarised above prevent us from ruling out a small
increased risk
