A Sensitive, Robust Method for Determining nNatural and Synthetic Hormones in Surface and Waste Waters by Continuous Solid Phase Extraction–Gas Chromatography–Mass Spectrometry

One recent trend in Analytical Chemistry is to develop economical, fast green methods using minimal amounts of solvents to determine a variety of analytes spanning a wide range of physicochemical properties. In this work, we developed a sensitive, selective method for the simultaneous determination of thirteen natural and synthetic hormones present at the nanogram-per-liter level in various types of water by using continuous solid phase extraction in combination with gas chromatography and mass spectrometry (GC–MS). The target analytes were preferentially sorbed on an Oasis HLB sorbent column and eluted with acetone for derivatization with a mixture of N,O-bis(trimethylsilyl) trifluoroacetamide and trimethylchlorosilane in a household microwave oven at 200 W for 4 min. Under optimum conditions, the ensuing method exhibited good linearity (r ≥ 0.998), good precision (RSD ≤ 7%), high recoveries (92–103%) and low detection limits (0.01–0.3 ng L− 1). The method outperforms existing alternatives in robustness, sensitivity, throughput, flexibility —it allows both estrogens, progestogens and androgens to be determined simultaneously— and compliance with the principles of Green Chemistry. It was successfully used to analyze various types of water samples (mineral, tap, well, pond, swimming pool, river and waste) that were found to contain four estrogens (estrone, 17β-estradiol, 17α-ethinylestradiol and hexestrol), two progestogens (testosterone, dihydrotestosterone) and one progestogen (progesterone) at concentrations ranging from 3.0 to 110 ng L− 1.