Synthesis of the available information about the radioactive contamination of the Japanese terrestrial environment caused by the Fukushima Dai-ichi accident - July 13, 2011

The French institute of radiation protection and nuclear safety (IRSN) collects and analyses regularly the published data concerning the contamination of the Japanese terrestrial environment caused by the Fukushima Dai-ichi power plant accident. This synthesis presents a status of the data recently obtained since the previous similar notes of April 12 and May 25. The note presents the detailed activity analysis of several surface soil samples (Iitate Maeda, Namie, Hirono, Fukushima..), a mapping of 137Cs and 134Cs cumulated deposits in a 80 km area around the damaged power plant, the evolution of radioactive deposits since March 2011 in different places (Fukushima, Hitachinaka, Saitama, Utsunomiya), the evolution of the 134Cs+137Cs and 131I contamination of agriculture food products and of drinking water. The IRSN has detected also a significant contamination of some tea samples imported from the Omaezaki region and intercepted by the French customs. Some information about tea and bamboo shoots cultivation and processing in Japan is added in appendix. (J.S.)