Images of the liver, gallbladder, and/or intestine were visualized on bone scans on several occasions. Radiopharmaceutical quality control data, including molybdenum-99 and aluminum ion content in the Tc-99m eluate, free unbound Tc-99m, and hydrolyzed reduced Tc-99m in the labeled MDP, were all satisfactory. A minor defect in the quality of the Tc-99m generator was considered to be the probable cause of the unusual localization of the bone imaging agent.