Figure 4

Comparison of atom ratios of 240Pu/239Pu in various environmental samples, radioactive particles, and source terms: global fallout15, soils during 1966–1977 in Japan16, soil after the FDNPP accident21,22, litter21,23, black substance23, vegetation24,25, river water26, average of air dusts27, and calculated result of reactor core28.