Environmental radioactivity analyses in Italy following the Fukushima Dai-ichi nuclear accident

Following the Fukushima power plants accident on the 11th March 2011, the radioactivity monitoring programme at the Italian ENEA research centres was activated in order to detect the possible new input of radionuclides through atmospheric transport and precipitation. Measurements of 131I and 134,137Cs were carried out on atmospheric particulate, atmospheric deposition, seawater and mussels and sheep milk. In the daily samples of air particulate, 131I was detectable between March 28 and April 12, with extremely low concentrations (<1 mBq m−3; the detection limit for 131I was ∼0.2 mBq m−3) while Cs isotopes were always below the detection limit (<0.2 mBq m−3). The two main episodes of 131I atmospheric deposition were registered in La Spezia research centre, around March 28 and April 15, reaching values of 17.8 ± 1.1 and 8.0 ± 2.5 Bq m−2 respectively; maximum values of 134Cs and 137Cs were 0.11 ± 0.03 and 0.17 ± 0.02 Bq m−2, respectively, detected in Brasimone research centre in April (reference date April 15). Mussels and seawater were collected in the Gulf of La Spezia: only mussels after the main 131I deposition, on March 28, contained a measurable, although very small, amount of 131I (0.18 ± 0.05 Bq kg−1, detection limit 131I = 0.03 Bq kg−1 wet weight – soft parts). The 131I was also detected in sheep milk in Rome (Casaccia research centre) until May 5, showing a maximum concentration of 4.9 ± 0.4 Bq L−1. As for other European Countries for which data are available, activity levels remain of no concern for public health.

► The Fukushima fallout in Italy showed the 131I maximum value of 17.8 ± 1.1 Bq m−2. ► The 134,137Cs maximum deposition was 0.11 ± 0.03 and 0.17 ± 0.02 Bq m−2, respectively. ► Radionuclide levels were 3 orders of magnitude lower than the Chernobyl fallout. ► 131I levels in sheep milk and mussels were of no concern for public health.