Validation of analytical methods for newly regulated veterinary drug residues in livestock and fishery products with maximum residue limits in Republic of Korea

Veterinary drugs play a crucial role in the treatment of various animal diseases. However, their residues, stemming from issues, such as withdrawal period lapses, overuse, or abuse, can jeopardize food safety and human health. This study addresses recent regulations in Korea concerning specific veterinary drugs (anacolin, ephedrine, menichlopholan, piperonyl butoxide, and etisazole HCl) and their ongoing discussions. This study aimed to validate two pre-developed methods for quantifying residues in livestock and fishery products using QuEChERS and liquid chromatography-tandem mass spectrometry. Both methods exhibited excellent linearity, recoveries (70.3-119%), and coefficient of variations (1.3-28%), along with low limits of detection and quantification (0.3-4 ng/g and 1-12 ng/g). This study is significant for its contribution to the detection of veterinary drugs in livestock and fishery products, given the limited research available on the methods for analyzing these substances.