Examinations of objects in the Ethnological Museum in Berlin showed that materials such as leather, fur, hair, hide, skins, and feathers contained highly toxic arsenic and mercury compounds as well as chlorine-containing pesticides such as DDT (dichlorodiphenyltrichloroethane), lindane (y-hexachlorocyclohexane), and PCP (pentachlorophenol). Normal cleaning techniques cannot remove the embedded residues from the heavy metals and pesticides that still remain in layers near the surface. A series of tests was carried out using high-pressure extraction with carbon dioxide. This method utilizes the good solvent properties of CO2, in its supercritical state (above 31°C and 73.8 bar). The survey was conducted in a laboratory plant for screening experiments of the Fraunhofer-Institute for Environmental, Safety and Energy Technology UMSICHT in Oberhausen, Nordrhein-Westfalen, Germany. The experiments have shown that ethnological objects, with the exception of fur, can be decontaminated without substantial damage to the materials through the use of supercritical carbon dioxide (SC-CO,) at 40°C and 350 bar.