Mobile phones are now being blamed for disrupting sleep patterns, according to research released this week by the Mobile Manufacturers Association.

The research was undertaken by the Electromagnetic Academy based at the Massachusetts Institute of Technology, in the US, and is sponsored by a research forum consisting of the likes of Nokia, Motorola, Samsung and Sony Ericsson.

According to the study, exposure to 884MHz wireless signals – such as those used by GSM 850MHz operators in the US – adversely affected the components of sleep, believed to be important for recovery from the day.

However, the research has drawn some criticism – reportedly even from within the Mobile Manufacturers Association itself – over the relatively small numbers of test subjects. Only 71 men and women, aged between 18 and 45, were exposed to mobile phone radiation as they prepared to sleep for the research.

Mike Dolan, of the Mobile Operators Association, a UK body designed to ensure operators gets a fair hearing within all public debate on the potential health effects of the deployment of radio technologies, called the research inconclusive. Speaking on BBC1 on Monday morning he said the effects of using a mobile phone in bed were no worse than drinking a cup of coffee before sleep.

This latest study follows swathes of research into the potential health effects of wireless technologies, of which little, if any, has provided grounds for concern.