Determination of phenols at the ng/1 level in drinking and river waters by liquid chromatography with UV and electrochemical detection.

Solid-liquid extraction of samples and liquid chromatography with UV and electrochemical detection with laboratory-made microcolumns were applied to the separation and identification of phenols and substituted phenols in waters. The compounds mainly studied were the eleven phenols considered as priority pollutants by the US Environmental Protection Agency. Chromatographic separation was carried out with several water-methanol isocratic mobile phases; use of the autoincrement mode of the electrochemical detector allowed the compounds in the samples to be confirmed. The chromatographic system worked automatically. The detection limits obtained with prior concentration of the samples were 40-600 ng/l, depending of the phenol. Electrochemical detection was used for the determination of phenols in river and drinking waters; phenols at the ng/l level was detected.