Radioactive pollution in Athens, Greece due to the Fukushima nuclear accident

As a result of the nuclear accident in Fukushima Dai-ichi power plant, which started on March 11, 2011, radioactive pollutants were transferred by air masses to various regions of the Northern hemisphere, including Europe. Very low concentrations of 131I, 137Cs and 134Cs in airborne particulate matter were measured in Athens, Greece during the period of March 24 to April 28, 2011. The maximum air concentration of 131I was measured on April 6, 2011 and equaled 490 ± 35 μBq m−3. The maximum values of the two cesium isotopes were measured on the same day and equaled 180 ± 40 μBq m−3 for 137Cs and 160 ± 30 μBq m−3 for 134Cs. The average activity ratio of 131I/137Cs in air was 3.0 ± 0.5, while the corresponding ratio of 137Cs/134Cs equaled 1.1 ± 0.3. No artificial radionuclides could be detected in air after April 28, 2011. Traces of 131I as a result of radioactive deposition were measured in grass, soil, sheep milk and meat. The total deposition of 131I (dry + wet) was 34 ± 4 Bq m−2, and of 137Cs was less than 10 Bq m−2. The maximum concentration of 131I in grass was 2.1 ± 0.4 Bg kg−1, while 134Cs was not detected. The maximum concentrations of 131I and 137Cs in sheep milk were 1.7 ± 0.16 Bq kg−1 and 0.6 ± 0.12 Bq kg−1 respectively. Concentrations of 131I up to 1.3 ± 0.2 Bq kg−1 were measured in sheep meat. Traces of 131I were found in a number of soil samples. The radiological impact of the Fukushima nuclear accident in Athens region was practically negligible, especially as compared to that of the Chernobyl accident and also to that of natural radioactivity.