Rapid determination of free and conjugated estrogen in different water matrices by liquid chromatography-tandem mass spectrometry

This article describes the development of a short pre-treatment method that allows the simultaneous analysis of free estrogens (estrone, 17 beta-estradiol, estriol and 17 alpha-ethynylestradiol) and their sulphate and glucuronide conjugated forms. For a range of matrices, from sewage effluent to river water, the developed methodology based on solid-phase extraction and fractionation technique with ultra-performance liquid chromatography system showed effective separation of the targeted estrogens. The detection limits of this method ranged from 0.2 to 0.8 ng L-1 for river water. The recoveries for river water and sewage effluent varied from 63% to 127%. The problems of matrix effects and ion suppression or enhancement were allowed quantitatively for in the analysis using standard addition. The developed method was used successfully to detect estrogens and their conjugates in both raw and treated wastewater, and river water at a location in Japan. High concentrations of the free estrogens estrone, 17 beta-estradiol and estriol were found in the influent (22.6, 77.2, 64.6 ng L-1, respectively) but only E1 was still present at a high concentration in the effluent which was reflected in the downstream river concentration. Estrone-3-sulphate was detected up to 18.0 ng L-1 in influent water sample and 1.1 ng L-1 in downstream water. For the sulphate conjugates, removal efficiencies varied from 35 to 88%. Glucuronide conjugates were detected only once in the sewage influent. (C) 2009 Elsevier Ltd. All rights reserved.