Fig. 3.

Examples of isoboles characterizing CuO-NP + ZnO-NP combined subchronic toxicity: (a) for thrombocrit (additivity); (b) for alkaline phosphatase (AF) in blood serum (subadditivity); (c) for testosterone (superadditivity of unidirectional action at low effect levels and oppositely directed action at high effect levels). The doses of CuO and ZnO are plotted on the axes in mg per rat. The numbers at the lines of the isoboles show the values of the effect Y (AF in IU/L; testosterone in nMol/L).