Analysis of Veterinary Growth Promoters in Airborne Particulate Matter by Liquid Chromatography–Tandem Mass Spectrometry

Abstract

Veterinary growth promoters are widely used throughout the United States in livestock production. In beef production, steroid hormones are administered to an estimated 90% of cattle. These include the synthetic steroids trenbolone acetate and melengestrol acetate, as well 17β-estradiol. Given the endocrine-modulating activity of steroid growth promoters, a sensitive and reliable analytical method is needed to detect trenbolone, melengestrol acetate, estradiol and related residues in environmental matrices. We have developed a method that incorporates solid phase extraction (SPE) and liquid chromatography–tandem mass spectrometry for the simultaneous determination of trendione, trenbolone, melengestrol acetate, estrone, and estradiol in airborne particulate matter samples. Sample preparation involved liquid-solid extraction followed by cleanup with SPE cartridges. Analytes were separated using reversed-phase liquid chromatography. Utilizing a fast gradient, analysis time was under 11 minutes, but did not provide complete isomeric separation of 17β-trenbolone and 17α-trenbolone, or 17β-estradiol and 17α-estradiol. Column effluent underwent atmospheric-pressure chemical ionization (APCI) followed by detection using a triple-quadrupole mass spectrometer in SRM mode. The lower limit of quantitation (LLOQ) was ≤0.55 ng/filter for all compounds. Recoveries ranged from 93% - 116%, and coefficient of variation (CV) was ≤16.1% at all spiking levels.