Determination of Hormones in Wastewater Using Rotating Disk Sorptive Extraction and Gas Chromatography–Mass Spectrometry

Abstract

ABSTRACTA simple and green analytical method based on the use of rotating disk sorptive extraction is reported for the simultaneous determination of hormones in wastewater. The analytes were 17β-estradiol, estriol, and 17α-ethinylestradiol. The analytes were separated and preconcentrated by rotating disk sorptive extraction and derivatized with N-methyl-N-(trimethylsilyl)trifluoroacetamide for determination by gas chromatography–mass spectrometry using (20,21)-13C2-17α-ethinylestradiol as a surrogate standard. Typical phases used in solid phase extraction of estrogenic hormones (C18 and divinylbenzene-N-vinylpyrrolidone copolymer) were tested in the rotating disk sorptive extraction, and a significantly higher recovery was obtained using divinylbenzene-N-vinylpyrrolidone copolymer. The optimum extraction conditions were a sample volume of 25 mL, a disk rotation velocity of 3000 rpm, an extraction time of 60 min, and a desorption time of 15 min using two portions of 4.5 mL methanol. Under these conditions, recoveries from 78 to 107% and 83 to 95% were obtained from the influent and effluent of wastewater treatment plants with relative standard deviations less than 8%. The method detection limits were between 5 and 39 ng L−1 depending on the analyte. The influent and effluent from wastewater treatment plants were analyzed, and the most polar compound, estriol, was found in influent at a concentration of 1.2 µ g L−1. An eco-scale was employed to assess the greenness of the method; the results showed that rotating disk sorptive extraction may be classified as a green methodology.