Trace analysis of selected hormones and sterols in river sediments by liquid chromatography-atmospheric pressure chemical ionization–tandem mass spectrometry

• New LC–MS method for determination of steroids in river sediments was developed.
• Chromatographic separation of analytes with identical fragmentations was achieved.
• Parameters that affect extraction and clean up efficiency were optimized.
• The method provided high recoveries, low limits of detection and quantification.
• In six sediment samples widespread occurrence of sterols and one hormone was found.

In this paper, development and optimization of new LC–MS method for determination of twenty selected hormones, human/animal and plant sterols in river sediments were described. Sediment samples were prepared using ultrasonic extraction and clean up with silica gel/anhydrous sodium sulphate cartridge. Extracts were analyzed by liquid chromatography-linear ion trap–tandem mass spectrometry, with atmospheric pressure chemical ionization. The optimized extraction parameters were extraction solvent (methanol), weight of the sediment (2 g) and time of ultrasonic extraction (3× 10 min). Successful chromatographic separation of hormones (estriol and estrone, 17α- and 17β-estradiol) and four human/animal sterols (epicoprostanol, coprostanol, α-cholestanol and β-cholestanol) that have identical fragmentation reactions was achieved. The developed and optimized method provided high recoveries (73–118%), low limits of detection (0.8–18 ng g−1) and quantification (2.5–60 ng g−1) with the RSDs generally lower than 20%. Applicability of the developed method was confirmed by analysis of six river sediment samples. A widespread occurrence of human/animal and plant sterols was found. The only detected hormone was mestranol in just one sediment sample.