Abstract: A method and apparatus for decontaminating molten metal compositions. A molten metal composition (typically containing elemental lead or a lead alloy) is initially provided which also includes various inorganic contaminants. The composition is placed in contact with a specialized decontamination member which actively allows diffusion of the contaminants therein. As a result, the contaminants are removed from the molten metal composition. Contaminants of particular interest in lead-based molten metal compositions include arsenic, tin, antimony, tellurium, and combinations thereof. A reducing agent is optimally combined with the molten metal composition to prevent oxide formation on the decontamination member. The decontamination member preferably contains iron in the form of an iron alloy (for example, steel). Additional preferred components in the decontamination system include an iron trap for removing iron-containing contaminants from the molten metal composition.