Accumulation and Determination of Phenylethanolamine A Residue in Hair of Swine and Sheep

The present study proposed the use of liquid chromatography-tandem mass spectrometry to detect the novel β-agonist phenylethanolamine A (PEA) in incurred hair samples of swine and sheep and to assess its accumulation for residue monitoring. The method showed good percent recoveries ranging from 93.2% to 102% and good coefficient of variation at <15%. The experiment was conducted in swine (24 treated and 4 controls) and sheep (3 treated and 1 control). PEA concentration was determined in hair during the treatment. High residue concentrations were present in hair as early as Day 24 (14.8 ± 3.6 and 25.8 ± 7.6 ng/g) and Day 21 (23.4 ± 6.6 ng/g) for swine and sheep; these residues persisted until withdrawal on Days 14 and 21. Results showed high PEA accumulation in hair, thereby indicating the use of hair as a matrix in the control of PEA abuse in farm animals.