[Quantitative determination of CO2-resorption from thermo-indifferent carbon dioxide mineral-water baths through human skin].

By means of mass spectrometric precision analysis of the natural variation of the 12C/13 relation in carbon dioxide of different provenience we contrive to pursue quantitatively the penetration of CO2 from the water of natural containing carbonic acid mineral baths (mineral springs Bad Elster) into the human body (skin--blood--expiratory air). First experiments confirm that in a bath of 21 or 20 minutes duration must be reckoned with a quantity of approximately equal to 24 ml . min-1 . m-2 of resorbed carbon dioxide and that the size of the basic metabolic rate of the bathing patient as well as the CO2 concentration of the bath water have an influence on the resorption process as well as on the measurement. On the other hand, the unspecific effect of the bath activating metabolism itself does not lead to a simulation of increased resorption rates. The borderline value for the penetration of CO2 through the skin seems to be 1.0 g . 1-1, i.e. within the region of the alkali reserve of the blood. The examinations are carried on.