title: [Radiochemical investigations on the decomposition of (mono) methyl-mercury by means of acid with regard to the determination of total mercury in fish (author's transl)].
abstract: Considerable amonts of mercury in fish muscle tissue are organically bound i.e. appear as (mono)methylmercury-compounds. In order to make mercury of organic origin available for the determination of total mercury by the "cold vapour atomic absorption method", a splitting of the carbon-mercury bond by means of suitable chemical treatment must be maintained beforehand. The main subject of this article are investigations with special regard to the behaviour of (mono)methylmercurychloride during different wet digestion methods. The procedures under study involve wet digestion under reflux with HNO3, with mixtures of HNO3 and HC10(4) and HNO3 and  H2SO4, as well as wet digestion with HNO3 in a closed system (pressure decomposition). The course of the decomposition of (mono)methylmercury dependent on time, temperature and concentration of reagents are discussed in detail. All experiments were controlled by measurement of the radioactivity of Hg-203 which had been added in the chemical form of CH3-Hg-Cl. From the analytical results obtained two methods of sample preparation have been derived that permit a reliable determination of total mercury in fish.
mesh_terms: D005396:Fish Products / Q000032:analysis*; D008628:Mercury / Q000032:analysis*; D008722:Methods; D009566:Nitrates; D010472:Perchlorates; D013464:Sulfuric Acids
chemical_list: D009566:Nitrates; D010472:Perchlorates; D013464:Sulfuric Acids; D008628:Mercury
vernacular_title: Radiochemische Untersuchungen über den Abbau von Monomethylquecksilber mit Säure im Hinblick auf die Gesamt-Quecksilberbestimmung in Fischen