Summary: Two examples of damages: Damages t o waters caused by surfaceactive polyethylene glycolacrylate (PEGA) waste waters and a fire extinguishing substance (30 n/o fatty alkyl sulphate and 15 ' )/ n ethylene glycol butyl ether) are analytically evaluated. A new method from polarography w-as described -the electrosorption analysis -, which was tested on the samples of the waste waters and waters of the events of damage. For comparison, investigations were carried out according to the conventional laboratory routine method. The described new method has shown pronounced advantages with respect to the detectability of substances contained in water and the expenditure of material and time. Individual tensides can be determined if known separation processes are applied in advance.