OCCUPATIONAL AND ENVIRONMENTAL MEDICINE
[Use of cellular telephones and brain tumour risk in urban and rural areas Occup Environ Med 2005; 62: 390-4]
Newswise — Using a mobile phone in rural areas seems to pose a greater risk of developing brain tumours than it does in urban areas, suggests a Swedish study in Occupational and Environmental Medicine.
The findings are based on a sample of over 1400 adults aged between 20 and 80, living in the centre of Sweden. All of them had been diagnosed with a malignant or benign brain tumour between January 1997 and June 2000.
The group were compared with a similar number of healthy adults, matched for age and sex, and living in the same geographical area.
Daily mobile and cordless phone use was assessed, via questionnaire, which included a complete employment history.
How long users spent on the phone had little impact on the probability of being diagnosed with a brain tumour. But where they lived did make a difference for all phone types, and especially for mobile digital phones.
Residents of rural areas, who had been using a mobile digital phone for more than three years, were over three times as likely to be diagnosed with a brain tumour as those living in urban areas.
And digital mobile phone use for five years or more in a rural area quadrupled the risk compared with residency in urban areas.
For malignant brain tumours, the risk was eight times as high for those living in a rural area, but the numbers were small, caution the authors. No such effect was seen for analogue or cordless phones.
The authors reiterate that there is a difference in power output between mobile phones in urban and rural areas. This is because base stations tend to be much further apart in rural areas, requiring a higher signal intensity to compensate.
The compensatory system, known as the adaptive power control or APC, is used for mobile phone (GSM) networks.
Click here to view the paper in full:http://press.psprings.co.uk/oem/june/390_om17434.pdf