The recent popularity and widespread use of mobile phones have led to great speculation that brain tumours may be caused by radiofrequency (RF) field from the use of mobile communication devices.
There has been an unprecedented growth in the use of mobile phones which is now arguably essential for daily living. For instance, there are currently about 50 million mobile phones in use in the United Kingdom (UK) compared with around 25 million in 2000 and 4.5 million in 1995 supported by about 40 000 base stations.
In less than ten years since the first GSM network was commercially launched as the second generation of mobile phones, it has become the world's leading and fastest growing telecommunications system. It is in use by more than one-sixth of the world's population and it has been estimated that at the end of January 2004 there were 1 billion GSM subscribers across more than 200 countries. The growth of GSM continues unabated with more than 160 million new customers in the last 12 months.
The extensive use of mobile phones suggests that users do not in general judge them to present a significant health hazard. Rather they have welcomed the technology and brought it into use in their everyday lives. Nevertheless, since their introduction, there have been persisting concerns about the possible impact of mobile phone technologies on health.
In 1999, the Independent Expert Group on Mobile Phones (IEGMP) was established to review the situation. Its report, Mobile Phones and Health (the Stewart Report), was published in May 2000. It stated:
“ The balance of evidence to date suggests that exposures to RF radiation below NRPB (National Radiological Protection Board) and ICNIRP (International Commission on Non-Ionising Radiation Protection) guidelines do not cause adverse health effects to the general population.”
There is now scientific evidence, however, which suggests that there may be biological effects occurring at exposures below these guidelines.
We conclude therefore that it is not possible at present to say that exposure to RF radiation, even at levels below national guidelines, is totally without potential adverse health effects, and that the gaps in knowledge are sufficient to justify a precautionary approach.
We recommend that a precautionary approach to the use of mobile phone technologies be adopted until much more detailed and scientifically robust information on any health effects becomes available.”
Similarly, the Advisory Group on Non-ionising Radiation (AGNIR) has also concluded that the amount of radiation from radiofrequency field is insufficient to result in carcinogenesis from DNA damage. The most recent report “Mobile Phones and Health 2004” by the National Radiological Protection Board (NRPB) also reported that there was no association between the mobile phone use and brain tumours 1.
The issue of mobile phone usage and brain tumours is however of great current interest in view of the global widespread use and dependence on mobile communication devices. Individual studies have have found positive correlations between high grade astrocytoma and phone use ipsilateral to the side of the tumours.
Hardell et al identified one cohort study and 13 case-control studies and the data was analysed for mobile phone usage >10 years and ipsilateral exposure if presented. The results showed that the use of mobile phones for >10 years give a consistent pattern of an increased risk for acoustic neuroma and glioma, most pronounced for high-grade glioma. The risk is highest for ipsilateral exposure 2. A meta-analysis by Lahkola et al however demonstrated no increased risk of brain tumours with mobile phone use greater than 5 years 3.
A large study conducted by Hepworth et al on a large cohort in United Kingdom also did not show any association between mobile phone usage and gliomas 4. It is however cautionary to note that the phenomenon of widespread use of mobile phones is a relatively recent and although there is currently no evidence to support the association between mobile phone usage and brain tumours in the short and medium term, the absolute effects of long-term usage may not be quantifiable at the present moment.
Dr Ng Wai Hoe
Consultant
Dept of Neurosurgery
National Neuroscience Institute
References
- Mobile Phones and Health 2004. Report by the Board of NRPB. Documents of the NRPB: Volume 15, No. 5.
- Hardell LO, Carlberg M, Soderqvist F, Hansson Mild K, Morgan LL (2007). Long-term use of cellular phones and brain tumours - increased risk associated with use for > 10 years. Occup Environ Med. Apr 4
- Lahkola A, Tokola K, Auvinen A (2006). Meta-analysis of mobile phone use and intracranial tumors. Scand J Work Environ Health. 32(3): 171-177.
- Hepworth SJ, Schoemaker MJ, Muir KR, Swerdlow AJ, van Tongeren MJ, McKinney PA (2006). Mobile phone use and risk of glioma in adults: case-control study. BMJ. 15;332(7546): 883-887.
