Parents should limit the time that children spend using their mobile phones, according to the chairman of an official study.

The recommendation follows the publication of a major document on mobile phones and health by the National Radiological Protection Board.

Although there is no hard evidence that people's health is being harmed by mobile phone technologies, the NRPB says uncertainties still remain and it recommends a precautionary approach until more is known.

Particular attention should be given to how best to minimise exposure of potentially vulnerable groups such as children and to consider the possibility that there may be other groups who may be particularly sensitive to radiowaves.

Other recommendations include ensuring that the public has access to the latest information about the use of mobile phones and masts while the planning process for mobile phone base stations should also be subject to independent review.

A continuing research programme on the possible health effects is strongly supported while high importance is placed on accumulating knowledge of exposure levels and possible biological effects of TETRA based technology used by the police.

NRPB chairman Sir William Stewart said: "In relation to mobile phone technology, our primary focus at NRPB is to ensure that the health and well-being of the general public is not being adversely affected by this technology.

"Today there are over 50 million mobile phones in use in the UK compared with 4.5 million a decade ago and numbers in use have doubled since 2000. The fact is that the use of mobile phones is now part of every-day life as an important means of easy communication by industry, security services, and the general public – and sometimes even as a fashion accessory. But because everyone has one does not necessarily mean that they are without potential adverse health effects."

He added: "The fact is that the widespread use of mobile phones is a relatively recent phenomenon and it is possible that adverse health effects could emerge after years of prolonged use. The evidence base necessary to allow us to make firm judgements has not yet been accumulated.

"What we can say is that there is as yet no hard evidence of adverse health effects on the general public, but because of the current uncertainties we recommend a continued precautionary approach to the use of mobile phone technologies. This approach should be adopted by all involved in this area – including government, the mobile phone industry and all who choose to purchase a mobile phone for themselves, or their family, or their children."