[Methods of vapour-phase extraction and extractive freezing for the analysis of organic substances dissolved in mineral waters of the Sochi spa area].

The chromatomass-spectrometry method was for the first time employed to study organic substances isolated by vapour-phase extraction from the Matseta sulfide-containing mineral water near Sochi. These substances are found to contain sulphur in different valent forms. A new technique has been developed for the detection of monobasic C2-C6 carboxylic acids in natural mineral water based on the combination of sequential vapour extraction and extractive freezing of the analytes. The proposed method is readily reproducible and has a detection limit of 0.03 mg/l for the analysis of carboxylic acids in water.