CHILDREN should be discouraged from putting their laptops on their lap when using wireless internet connections because of potential health risks, an expert has warned.

Youngsters should be monitored as public concern continues over emissions from wi-fi networks, Professor Lawrie Challis, who heads the committee on mobile phone safety research, said.

Until more research is carried out, children should keep a safe distance from the embedded antennas on wi-fi enabled laptops.

"With a desktop computer, the transmitter will be in the tower," he said. "This might be perhaps 20cms from your leg and the exposure would then be around one per cent of that from a mobile."

But if a laptop was placed straight on the lap when using wi-fi, people could be around 2cm from the transmitter, and receiving comparable exposure to that from a mobile phone, he said.

"We advise that children should be discouraged from using mobiles, so we should also discourage children from placing their laptop on their lap when using wi-fi."