The mast crusaders

Mandy's children are having nosebleeds. Andy sleeps with metal plates by his bed. Beat bobbies are reporting strange illnesses. They all blame the new police radio system

The ill-fated Cornish revolt of 1497 began in the pretty, isolated village of St Keverne on the Lizard peninsula, as a protest over unjust taxes levied by London. Now, its population has rebelled once more against an idea imposed from afar, which they believe could have been far more damaging than any mere financial loss.

The ill-fated Cornish revolt of 1497 began in the pretty, isolated village of St Keverne on the Lizard peninsula, as a protest over unjust taxes levied by London. Now, its population has rebelled once more against an idea imposed from afar, which they believe could have been far more damaging than any mere financial loss.

This time the population has had more success than in 1497, when its leaders were executed. They have won their point and become one of the few communities in the country to be without a Tetra radio mast. "It's not as though we aren't already chock-a-block with radio masts and aerials around here: there's the BT Satellite Earth Station at Goonhilly, and RAF Culdrose up the road," says John Gough, spokesman for the anti-Tetra campaigners. "But when we saw they were going to put up a Tetra mast, we decided to find out about it on the internet. We were immediately very concerned." More than 350 people out of a total population of only 1,600 lodged objections to the local planning committee, which rejected the application to erect the 50ft-high mast on farmland near the village.

It was the experiences of others elsewhere that motivated the St Keverne campaign. They learnt of stories like that of Andy Davidson in Worthing who, suffering headaches and insomnia, had to sleep with metal plates around his head; and of the 80 people around Dursley in the Cotswolds who claim to have suffered similar problems, one of whom has covered her bedroom windows with metal mesh to stop the symptoms. They also learnt of Mandy Keeling and her family in Bognor Regis, whose sickness and sleeplessness ended when the local Tetra mast was taken down.

You may not have heard of Tetra masts, but there's almost certainly one near you. If not, it's on the way. Tetra - Terrestrial Trunked Radio - is the new police communications network that is replacing their outdated, unreliable VHF system. It gives officers a mobile phone and two-way radio in the same handset, and is being implemented around the country by O2 Airwave, previously part of BT, which has a £2.9bn, 15-year contract with the Home Office to supply all 51 forces in England, Wales and Scotland through a network of around 3,500 masts. Around 40 forces have been supplied so far, but the system will not be fully operational until May 2006.

Around 70 per cent of Tetra masts have been, or will be, built on sites already in use; some replace old masts, others are added to existing ones. The remainder are new masts, such as St Keverne, requested by police to improve communications in remote areas. The Home Office says it chose the Tetra system, which is used in 65 countries, in preference to others such as the French-based Tetrapol, used in about 28 countries, because it is technically superior. It was criticised by the House of Commons Public Accounts Committee for failing to incorporate financial safeguards in case the health fears proved justified, and by the EC for refusing to accept tenders from non-Tetra operators.

But the programme's completionnext year is unlikely to be the end of Tetra installations. O2 Airwave is short-listed for the contracts to supply the fire and ambulance services; this may lead to further masts. If Airwave is not awarded the multimillion-pound contracts when the decisions are announced over the next two months, it will be seen as a victory for anti-Tetra campaigners and evidence of a lack of official faith in the Tetra network.

Although the health fears surrounding Tetra are linked to concerns about mobile-phone masts, the symptoms that affect some people appear consistent - sleep deprivation, nausea, headaches, ear pressure, nosebleeds. They seem to stop when the Tetra exposure ends. They occur, it is claimed, because the masts transmit and receive signals on the 400 MHz frequency, which are pulsed at 17.65Hz. In 2000, the Government's report on mobile-phone safety by Sir William Stewart, a former chief scientific adviser, recommended that frequencies around 16Hz - the frequency at which the human brain transmits signals - be avoided as a precaution, even though there was no confirmed health risk.

Campaigners say the apparent link between cause and effect underlines their concerns about Tetra. In Bognor Regis 44-year-old Mandy Keeling began to vomit last New Year's Eve. "It was the day, I later learnt, that the Tetra mast 150 yards from my home began transmitting. I had two months of nausea, headaches and poor sleep. Doctors could do nothing. Then I heard about the mast. I was cynical about it at first. I thought, 'Pull yourself together.' I've lived here for 12 years, and there are other mobile masts, but none had made my brain vibrate." By now her two sons, aged nine and 19, were suffering, too; the younger one had nosebleeds.

She went knocking on doors and discovered neighbours had been affected as well. They campaigned to have the mast taken down; eventually, the company agreed. The mast was dismantled in May. Keeling was transformed: "I felt better within a month, and we're all perfectly healthy now. Except when I go near a Tetra mast somewhere else."

What seems clear is that, if Tetra does have an affect, it is only triggered in those who are sensitive to low-frequency radio waves are directly exposed. After months of sleeplessness and headaches, Andy Davidson's solution was to take a couple of metal plates and place them around his pillow to block out the signals from the transmitter across the playing-field; both the mattress and the plates were earthed. It worked. "It may be strange, but it's the only way I can get a decent night's sleep," he says. But his wife and children have not suffered, and a survey of more than 400 local people showed that, while around 40 per cent had suffered from sleeplessness and/or headaches since the mast arrived, everyone else was OK. Davidson is now moving house.

His case is one of hundreds of examples collected by Tetrawatch, the national campaign against Tetra, which has gathered force as Tetra has been rolled out around the country over the past three years. Tetrawatch argues that the system is untested; is being imposed secretively; is shunned by many other European countries, including France; and that health fears are being underplayed by the Government in the same way that, say, the link between CJD and BSE was in the early 1990s.

John O'Brien, the spokesman, stressed that the Tetra system in this country is different to both Tetrapol and other Tetra systems elsewhere, because to meet police requirements it uses the pulsed technique, which is feared to create the symptoms. "This is an untried and untested system. There is something different about this type of Tetra system compared with other mobile transmissions systems, and that is why we're worried about it." And concern isn't confined to people living near base stations - a number of landowners, including Lord Cowdray and the Duke of Norfolk, have refused to allow Tetra masts on their land.

And then there are the police officers, who are being exposed every day. When Tetra first began, the Police Federation, which represents lower-ranking officers, commissioned a report by an independent physicist, Barrie Trower. He predicted the occurrence of cancers resulting from Tetra and warned that the system could lead to "more civilian deaths in peacetime than all the terrorist organisations put together". But it was too late. Tetra was already being rolled out around the country.

One of the first forces to go "live" was Lancashire, in 2001. Within a short space of time, more than 170 officers out of a force of 3,500 were reporting the typical symptoms. But, says Steve Edwards, chairman of the local branch of the Police Federation, complaints have tailed off. "If my members were suffering on a daily basis, they would be knocking on my door every day. They are not. Opinion is divided. I can't tell members it's safe, but I can't say it's definitely going to damage their health."

But concerns remain. In Leicestershire, PC Neil Dring, an otherwise healthy motorcycle officer, suffered headaches and nosebleeds soon after being issued with his Tetra handset. He developed oesophageal cancer and died this summer. His family believe the cancer was linked to his handset, which he wore strapped to his body. Another officer in the force has also developed the same relatively unusual cancer.

It is not, says Steve Edwards, as though the Tetra handset is even the answer to all police communication needs. "Tetra hasn't delivered yet. It's encrypted, so it's more secure than VHF, but it can't yet do all the things we were told it would, like send photos, link to the police national computer, or allow communication between officers in different forces. We hope it will be better when the whole system is up and running."

Medical opinion is divided. On one side are the "establishment" scientists, such as Professor Colin Blakemore, chief executive of the Medical Research Council, who say there's no evidence that Tetra is unsafe; on the other, independent consultants such as Dr Gerard Hyland, a former head of physics at the University of Warwick, who believe otherwise. "We could be seeing a pandemic of brain tumours in 10 years," he told The Ecologist recently. Earlier this year, the National Radiological Protection Board (NRPB), the independent watchdog, concluded: "Although areas of uncertainty remain about the biological effects of low-level RF radiation... current evidence suggests it is unlikely that the special features of signals from Tetra mobile terminals and repeaters pose a hazard to health."

Curiously, The Ecologist pointed out, there is now what some see as evidence of official backtracking on the Stewart report. Professor Blakemore, a member of the NRPB's advisory group and the Stewart committee, said16Hz radio waves provide "no cause for alarm. I still hold to both of my previous statements. In principle, it would have been better if 16Hz pulsing could have been avoided. But that was said in the context of the strict precautionary approach of the Stewart report." Professor Lawrie Challis, deputy chairman of the Stewart committee, said the 16Hz warning was made in recognition of the existence of "unreplicated research from the 1970s", and there was "no evidence that 17.65Hz modulation of the emission from Tetra phones would lead to any adverse health effects".

Tetrawatch questions the NRPB's independence from the vested interests of the Home Office and the mobile-phone industry. Answering the criticisms, Home Office ministers and Airwave cite the technical virtues of Tetra, and refer health concerns to the conclusions of the NRPB. The Home Office says some symptoms suffered are, like those associated with mobile-phone masts, often related to stress caused by a perception of risk, rather than the reality; whether some people are genuinely sensitive to certain radio waves, it says, must be the subject of further research. It has also commissioned a 10-year study of police handsets by Imperial College London. But Tetrawatch says if its fears are justified, any results will come too late.

Airwave adds that gaining the fire and ambulance contracts would help to provide an integrated national system with only "minimal" increase in the number of masts; that it operates within recommended NRPB safety levels; and that the handsets pulse, the masts do not. But such assurances are not enough for Mandy Keeling: "If a food you could buy on the high street had all these concerns raised about it, it'd be off the shelves straight away."

Back in St Keverne, John Gough, a 69-year-old retired research chemist, believes they have saved the village from an experiment with uncertain consequences: "I'm a scientist and was a radar mechanic in the Army, so I know a bit about radiation. Nobody can give us any assurances about the long-term effects of low-level frequencies, and I don't see why anybody, anywhere, should be used as a guinea pig for this."