Radioactivity survey data in Japan. Pt. 1. Environmental materials

This is a compilation of radioactivity survey data in environmental materials, which were collected during the period between October 1992 and December 1993. The samples were sent to the Japan Chemical Analysis Center from 46 contracted prefectures. The samples were prepared for radiochemical analysis. The concentrations of 90Sr and 137Cs in respective samples are tabulated. The maximum concentrations of 90Sr and 137Cs were 0.20±0.12 MBq/km2 from Fukui (December 1992) and 1.1±0.05 MBq/km2 from Tochigi (March 1993), respectively, for rain and dry fallout (for domestic program); 0.30±0.024 MBq/km2 from Niigata (November 1992) and 0.11±0.021 MBq/km2 from Niigata (February 1993) for rain and dry fallout (for WHO program); 0.0027±0.0013 mBq/m3 from Fukushima (January-March 1993) and 0.0013±0.00080 mBq/m3 from Aichi (October-December 1992) for airborne dust; 4.4±0.41 mBq/l from Shiga (December 1992) and 0.25±0.088 mBq/l from Niigata (December 1992) for service water; 4.9±0.18 mBq/l from Niigata (November 1992) and 0.25±0.097 mBq/l from Nagano (December 1992) for freshwater; 2.3±0.20 and 3.5±0.39 mBq/l from Kagoshima (December 1992) for sea water; 0.037±0.049 and 0.29±0.082 Bq/kg·dried soil from Kagoshima (December 1992) for sea sediments. Annual variations in the concentrations of 90Sr and 137Cs in environmental samples are given in figures. (N.K.)