Members of the Association of Teachers and Lecturers (ATL) said they were concerned by scientific reports linking wi-fi with impaired concentration, loss of short-term memory, chromosome damage and increased incidence of cancer.

Wi-fi systems use high frequency radio waves to transmit and receive data over distances of several hundred feet. They allow users to surf the internet on demand within range of a wireless transmitter and remove the need to connect via a cable.

According to ATL, 70 per cent of secondary schools and 50 per cent of primaries in the UK use wi-fi, even though no longterm studies have been carried out into the health effects of wireless networks.

Speaking at the ALT's annual conference, Colin Kinney, a teacher at Cookstown High School in Northern Ireland, said that international experts had called for caution when using wi-fi technology. He said research from Sweden had warned about the increased cancer risk and the Government there now funds shielding agents, such as foil covered rooms and anti-radiation points.

Mr Kinney said a Government scientist from Austria had called for wi-fi to be removed from schools, claiming there was evidence of “increased symptoms as well as increased cancer rates”.

"Have we the moral right to ignore the warnings – simply for access to a few more computers – and are our pupils going to thank us in the years to come if they have become sterile or suffer from cancer brought on by, or exacerbated by, exposure to wi-fi?" Kinney asked.

"Perhaps they will just be eternally grateful that we enabled them to finish their presentation for geography."

Mr Kinney demanded a return to wired internet access until long-term studies had confirmed the safety of the wireless technology. 
 
"As teachers, we may have to wait a little longer for the new ICT (information and communication technology) suite to become available, but at least we will be safeguarding health."

However, Dr Michael Clark, scientific spokesman for the Health Protection Agency (HPA), said there was no evidence the technology had any detrimental effect.

"On the basis of research so far, there is no hard evidence of any ill health effects from wi-fi. The signals are very low, in fact there is more wattage coming from the battery," he said

A spokeswoman for the Scottish Government agreed:

"Based on the advice from our principal advisors, the Health Protection Agency, there is no consistent evidence to date that wi-fi adversely affects the health of the general population," she said.

But schoolteacher Kinney pointed out that Sir William Stewart, chairman of the Health Protection Agency, had called for a precautionary approach when siting masts near schools.

Now this prudent course of action had been all but abandoned and the attitude of the Government was to “roll it out and don't stop until someone proves a risk”, Mr Kenney said.

The spokeswoman for the Scottish Government gave an assurance that the Health Protection Agency intended to carry out "a research project to measure the effects of radio signals from wireless networks". She said the results of the study would be used to inform future policy on the technology.

Previously, the Professional Association of Teachers had called for classroom wi-fi networks to be halted until potential dangers were known.

IN 2007, a BBC Panorama investigation found that, at its peak, the radiation from a wi-fi enabled laptop computer is three times that of a mobile-phone mast. (Sources: Scotsman; Daily Mail)