A granulate that consists of broken pieces of a sintered body that is sintered from crushed blow-molded glass has a number of inclusions of at least one active substance on the broken surfaces of granulate. This active substance is embedded as a grain in sintered body. Upon contact with toxins, in particular with toxins that are suspended or dissolved in water, this active substance can interact with these toxins. Such a granulate can be produced very readily relative to active substance, compressive strength, specific weight, grain size, etc., and can be used correspondingly in a versatile manner. Despite arsenic- or antimony-containing starting substances, it can be used, for example, in the form of foam glass broken pieces as a construction material in environmentally-sensitive areas. It can be used, e.g., in the form of expanded or unexpanded sintered bodies in water purification. Depending on the intended use, metals, in particular metallic iron, active carbon or else water-soluble substances, can be used as active substances.