Radionuclides in imported foods consumed in Hokkaido were examined by germanium (Ge) gamma-ray spectrometer system. The values of radioactive cesium (137Cs+134Cs) concentration of 480 samples collected during 1989-1999 were lower than the temporary limit (370Bq/kg) . These values of 441 samples (92%) were lower than 1 Bq/kg. The maximum values of137Cs and134Cs were 62.4Bq/kg, 3.8Bq/kg in black tea imported from China. From the relation between concentration of137Cs and cesium unit, the contribution from Chernobyl reactor accident was estimated qualitatively on 24 samples with higher values than 0.40Bq/g-K. Based on the concentration of134Cs and137Cs detected in 16 samples, the contribution of137Cs from this accident were calculated.
Atmospheric concentrations of210Pb were observed in the eastern area of the People's Republic of China with aerosol samples. Observations were carried out intermittently during the period from April, 1989 to December, 1992 at Beijing and Chengdu. The atmospheric concentrations of210Pb ranged from 0.9 to 4.6 mBq/m3at Beijing and from 1.4 to 7.8 mBq/m3at Chengdu, respectively, which were in the similar level to those observed previously in the inland area of the Chinese Continent. Seasonal variations of the210Pb concentration show the“one peak”variation pattern: the maximum levels were recorded in winter season. Small additional rises in the atmospheric210Pb concentrations observed in the period from spring to autumn seasons may be due to complicated meteorology with high pressure systems at Beijing and due to the topographical situation at Chengdu.