In the late 1990s, several recent expert groups have reviewed critically the current evidence concerning the health effects of low-level exposures to radio frequency (RF) electromagnetic fields (WHO 1996, McKinlay et al. 1997, Repacholi, 1998). In view of the state of knowledge at that time concerning the possible adverse health effects of RF exposure, and of the increasingly widespread use of portable telephones in many countries, these groups recommended that research be carried out to determine whether radiotelephones could cause adverse health effects.
As a result of these recommendations, a detailed feasibility study was carried out in 1998 and 1999 in fourteen countries, co-ordinated by the International Agency for Research on Cancer (IARC) in Lyon. Using criteria established in advance, it was concluded that an international study of the relation between mobile telephone use and brain cancer risk is feasible and informative.
A series of multi-national case-control studies has therefore been set-up, co-ordinated by IARC. Separate studies are being carried out for acoustic neurinoma, gliomas and meningiomas and, in some countries, tumours of the parotid gland, the tumours that, if RF are carcinogenic, would be most likely to be related to mobile telephone use.
The studies are based on a common "core" protocol, describing common procedures to be followed in all participating countries. National studies, however, may have specific features or a wider scope than the international study.
Participating countries are Australia, Canada, Denmark, Finland, France, Germany, Israel, Italy, Japan, New Zealand, Norway, Sweden and the UK. In order to maximise the statistical power of finding a risk if it exists, the studies are mainly focused on tumours in relatively young people (30-59 years of age - who had the highest prevalence of mobile phone use in the late 1980s and 1990s) and on regions within the participating countries with longest and highest use of mobile phones.