Emergency monitoring stationsat Oxfordshire and Glasgow in the UK have detected traces of radioactivity believed to be from the Fukushima nuclear disaster in Japan.
The Health Protection Agency (HPA) has said the levels of radioactive iodine detected at its air monitoring stations over the last nine days, posed no risk to health.
Though the readings touched the level of 300 micro-becquerels per cubic metre, on an average over the nine-day period, the level was a barely detectable 11 micro-becquerels.
Similar findings have been reported by monitoring stations in Switzerland and Germany.
According to the HPA the dose from breathing in air "was minuscule and would be very much less than the annual background radiation dose".
It added the development was not unanticipated in the wake of the Fukushima crisis, where four reactors have suffered serious damage and have emitted significant levels of radiation, in one of the world's worst civil nuclear disasters.