PERSONAL breathalysers used by motorists to detect potentially unsafe levels of alcohol vary significantly in their effectiveness, researchers warn today.
Experts tested three different products available in pharmacies on 200 people drinking in Oxford. They estimated they had drunk an average of six units of alcohol during the evening although at least one drinker estimated they had consumed more than 12 pints.
Readings were compared with a device used by the police to carry out roadside tests which found almost one in five were at or over the limit.
One device picked up only around one in four people over the limit, another 90 per cent and the third detected 95 per cent, which researchers said meant one in 20 people would still be given false reassurance.
They said the findings, published in the journal BMJ Open, called into question the regulatory process for approving devices for personal use, particularly as false reassurance about safe driving could have “potentially catastrophic consequences”.
They added: “Our research suggests that at least some personal breathalysers available for sale to the public are not always sufficiently sensitive to test safety to drive after drinking alcohol, where use of inaccurate information from breathalysers, thought to be accurate, could have catastrophic safety implications for drivers.”
They add: “The fact that these devices are sold in well-established pharmacies, including national chains, does not guarantee sufficient accuracy for safe use.”