Scientists discover radioactive flagstone on beach

A FLAGSTONE on a Caithness beach was discovered to be radioactive during routine monitoring, a new report has revealed.

The flagstone and another stone were found to be contaminated with caesium-137 associated with discharges from nearby Dounreay.

Caesium-137 is the principal source of radioactive contamination in the food chain, mainly due to atmospheric nuclear bomb tests and the Chernobyl accident.

It is caused by the nuclear fission of uranium-235 and other fissionable isotopes in nuclear reactors and nuclear weapons. It is also among the most problematic of the short-to-medium-lifetime fission products because it easily moves and spreads in nature due to the high water solubility of caesium’s most common chemical compounds.

The contaminated caesium-137 stones were removed earlier this year, the latest Radioactivity in Food and the Environment Report published yesterday reveals.

Sand-sized fragments of irradiated nuclear fuel were flushed into the sea from Dounreay in the 1960s and 1970s. Hundreds have been found and removed from beaches over the years.

Particles of irradiated nuclear fuel were first detected on the Dounreay site coastal strip in 1983 and on the beach at Sandside in 1984.

Dr Paul Dale, principal policy officer from the Scottish Environment Protection Agency, said: “This year’s report again demonstrates that Scotland’s public is adequately protected against sources of radioactivity that could impact on our food and the wider natural environment.”