Fig. 2. Effect of calcium–phytate precipitate (Ca_n–IP6), dodeca sodium–phytate (Na₁₂–IP6), and hydroxyapatite (HA) addition on soluble U (A and B) and Ni (C) after equilibration for 136 h in 0.001 M CaCl₂. B reflects the expanded scale for A. Error bars represent the standard deviation of the treatment means.