Breakthrough curves were measured for Cd2+, Cu2+ and Pb2+ in their single, binary and ternary nitrate aqueous solution systems using a fixed bed of hydroxyapatite particles in order to obtain volumetric mass transfer coefficients. Breakthrough curves for Pb2+ showed particular profiles depending on the pH of influent solutions in the bed. For the binary and ternary systems containing Pb2+, the curves for each ion showed that Pb2+ displaced not only calcium but also other co-existent ions which were already collected in the substrate. It was considered that Cd2+ and Cu2+ were collected in the vicinity of the internal surface of particles, but the uptake of Pb2+ occurred in the interior as well as at the internal surface of hydroxyapatite particles.