Environmental radioactivity measurements in north-western Greece following the Fukushima nuclear accident

The impact of the Fukushima nuclear accident in north-western Greece was assessed through an environmental monitoring programme activated by the Nuclear Physics Laboratory of the University of Ioannina. Measurements of I-131 were carried out in atmospheric particulate, ovine milk and grass samples. In daily aerosol samplings, radioiodine was first detected on March 25-26, 2011 and reached maximum levels, up to 294 mu Bq m(-3), between April 2 and April 4, 2011. In ovine milk samples, I-131 concentrations ranged from 2.0 to 2.7 Bq L-1 between April 2 and April 6, 2011, while an average activity of 2.7 Bq kg(-1) was measured in grass samples on April 4, 2011. The Cs-134,Cs-137 isotopes were below detection limits in all samples and could only be determined in the air, by analysis of multiple daily filters. A maximum average activity concentration of Cs-137 amounting to 24 mu Bq m(-3) was measured during the period from April 5 to April 9, 2011, with the Cs-134/Cs-137 activity ratio being close to unity. Activity concentrations were consistent with measurements conducted in other parts of the country and were well below those reported in May 1986 after the Chernobyl accident. The committed effective dose to the whole body and to the thyroid gland from inhalation of I-131 was estimated for the adult and infant population and was found to be of no concern for the public health.