The amount of radiation emitted by a mobile phone may be increased up to three and a half times when used with a hands-free kit, according to a study released by the Consumers' Association Thursday. The report contradicts a study released by the DTI in August and is a major embarrassment for e-minister Patricia Hewitt who has gone on record saying hands-free kit is safe. A statement from the Consumers' Association says: "As in earlier tests it is clear that consumers cannot rely on hands-free kits to reduce radiation emissions [to] the brain." Which? editor Helen Parker criticised Hewitt for giving mobiles the all-clear too soon. "It was unwise to give out such categorical advice at the time," says Parker. The research has been greeted with "some reservation" by the Department of Trade and Industry which rejected the Association's earlier report, released in April. A DTI spokeswoman said: "We have what may be material reservations about the methodology used by the Consumers' Association... Our original report has not been criticised." But the Consumers' Association made a point of criticising the DTI's methodology, arguing that its protocols did not represent typical use of a mobile phone. A spokeswoman told ZDNet UK News: "The DTI's tests used a dummy with a mobile phone attached to its shoulder. I've never seen anyone with a mobile attached to their shoulder. It's not normal use and the position of the [hands-free] wire between the earpiece and the tip of the aerial is critical in showing variations in the levels of radiation. For this reason we believe the DTI's methodology was at fault." Asked if consumers would be confused by the different research results, the DTI spokeswoman refused to answer the question. The Consumers' Association tested three different commercially available phones and hands-free kits, from Nokia, Panasonic and Phillips. The tests showed that while all operated within European guidelines controlling emissions, hands-free kits cannot be expected to routinely lower radiation levels. The research supports the Consumers' Association's earlier research on hands-free equipment. That study suggested hands-free kits could amplify radiation from mobiles. "Although these kits can reduce radiation, they can also increase it significantly, depending on where you position the phone and kit. Unfortunately, there is no way that a consumer can work out the best position to reduce radiation." In August, the DTI produced its own research, using a test called a Specific Absorption Rate (SAR) test, which reinforced the popular belief that hands-free kits reduce radiation. The Consumers' Association says that its research, carried out by ERA Technology and which included SAR tests, indicates that the DTI's missed key findings. It says that SAR tests do not take into account the effect that the positioning of hands-free equipment has on radiation and does not look specifically at radiation emitted at the ear. The Consumers' Association called for further research by government and industry and recommends the development of European standards for testing the safety of hands-free devices. Although the amount of radiation emitted by mobile phones is restricted by UK law, it is not absolutely clear whether phone radiation actually damages health. The Stewart Report, a government-commissioned study published in May on the effects of mobile phone radiation on the brain, failed to prove conclusively whether there is a risk or not but called for more investigation. The Consumers' Association recommends that, if consumers are concerned about exposure to radiation, they do not rely on hands-free kits but reduce their overall phone use. To have your say online click on the TalkBack button and go to the ZDNet News forum. Let the editors know what you think in the Mailroon. And read what others have said.