Using a mobile phone for long periods may raise risk of brain tumours

According to Swedish researchers using a mobile phone for long periods of time raises the risk of brain tumours.

The study completely contradicts conclusions arrived at by other studies and re-opens the debate over the safety of pro-longed use of mobile phones.

In 2005 researchers at the Dutch Health Council conducted a review of research from around the world and found no evidence that radiation from mobile phones and TV towers was harmful.

A British survey carried out over a period of 4 years and published early this year also showed no link between regular, long-term use of cell phones and the most common type of tumour.

As the majority of the population of the developed world, in particular youngsters, seems to spend a large bulk of their time speaking on their mobiles, the results of this latest study is a worry.

The researchers at the Swedish National Institute for Working Life looked at the mobile phone use of 2,200 cancer patients and an equal number of healthy control cases.

They found that of the cancer patients who were aged between 20 and 80, 905 had a malignant brain tumour and about a tenth of them were also heavy users of mobile phones.

The study authors say of the 905 cases, 85 were high users of mobile phones; they began to use mobile and/or wireless telephones before the age of 20 and used them frequently.

The study definition of heavy use was 2,000 plus hours, which "corresponds to 10 years" use in the work place for one hour per day".

The study also found there was a noticeable increase in the risk of tumour on the side of the head where the telephone was generally used.

The study also considered factors such as smoking habits, working history and exposure to other agents.

Lead author Kjell Mild, says the figures mean that heavy users of mobile phones have a 240 percent increased risk of a malignant tumour on the side of the head the phone is used.

Mild says the study is the largest yet to look at long-term users of the wireless phone, which have been used in Sweden in a portable form since 1984, which is longer than in many other countries.

The study is published in the International Archives of Occupational and Environmental Health.