Determination and surveillance of hydrocortisone and progesterone in livestock products by liquid chromatography-tandem mass spectrometry.

A simple analytical method for the determination of hydrocortisone and progesterone in bovine, swine, and chicken muscle and eggs was developed. Hydrocortisone and progesterone were extracted with acetonitrile and subsequently cleaned-up using an Oasis HLB mini-cartridge. The method was validated in accordance with Japanese guidelines and exhibited trueness from 86.6% to 104.3% and precision (relative standard deviations (RSDs) of repeatability and within reproducibility were under 8.7% and 11.7%, respectively). The method was applied to 103 bovine muscle, 137 swine muscle, 69 chicken muscle and 52 egg samples that were commercially available in Tokyo, Japan. The hydrocortisone concentration was 0.9-41.2 µg kg(-1) in all bovine muscle samples, with an average of 7.7 µg kg(-1) and a median of 6.2 µg kg(-1). The progesterone concentration in 50 samples exceeded the limit of quantification (LOQ) and reached a maximum of 95.4 µg kg(-1). Hydrocortisone was also detected in all swine muscle samples at concentrations of 2.0-56.0 µg kg(-1). Its average and median concentrations amounted to 13.1 and 11.3 µg kg(-1), respectively. Twenty-three samples contained progesterone levels surpassing the LOQ, with a maximum concentration of 107.0 µg kg(-1). No chicken muscle samples contained any of the analytes. The progesterone concentration was 15.5-200.0 µg kg(-1) in all egg samples, with an average of 95.4 µg kg(-1) and a median of 90.5 µg kg(-1).