The toxicity of fullerene derivatives evaluated with bioluminescence inhibition assay. The examples of E. coli K12 TG1 lac::luxCDABE luminescence time course during contact with aqueous suspensions of F10 (a) and F8 (b) compounds, and the dose–response curves described the changes in the bioluminescence inhibition indexes caused by differing content of penta-substituted fullerene derivatives’ (c). Designations (a, b): ordinate—bioluminescence, RLU; abscissa—time measurement, min. Compounds concentrations: 1 2000 μmol; 2 1000 μmol; 3 500 μmol; 4 250 μmol; 5 125 μmol; 6 62.5 μmol; 7 31.25 μmol; c control. Designations (c): ordinate—bioluminescence inhibition index, I; abscissa—fullerene derivatives concentrations, μmol.