Results demonstrate that a significant proportion of Pb and Cd removal was mediated by surface binding of metals (85 % Pb and 79 % Cd), rather than by intracellular accumulation (5 % Pb and 4 % Cd) at the optimum level of cyanobacterial biomass (2.8 g L−1), metal concentration (80 μg mL−1), pH (pH 5.0–6.0), time (15–30 min), and temperature (30–40 °C).