Optimization and Validation of a Quick and Responsive LC-ESI-MS/MS Method to Evaluate Tetracyclines Residues in Processed Animal Proteins (PAPs)

Abstract

Background Following the bovine spongiform encephalopathy (BSE) in 2001, processed animal proteins (PAPs) reintroduction is envisaged in non-ruminant feed thanks to their high protein content, easy availability and cost-effective characteristics. PAPs must be submitted to rendering practices, providing sterilization of products, under standardized conditions of temperature and pressure, according to Regulation (EC) No 142/2011. However, the chemical risk associated to these raw materials has been never evaluated. The aim of this study was to develop and validate a reliable liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the determination and quantification of tetracycline residues in PAPs at µg kg− 1 level. Methods The LC-MS/MS method performances were evaluated in terms of specificity, linearity (25–500 µg kg− 1), limit of quantitation (LOQ) (25 µg kg− 1), accuracy and precision (CV% <25%), uncertainty, recovery (80–120%) and ruggedness. Results All the evaluated parameters fulfilled the analytical performance criteria and the validated LC-MS/MS method fits for purpose as confirmatory method on the occurrence of residues (µg kg− 1) of TCLs in PAPs. Conclusions PAPs are a powerful product which could be used both as raw material in feed and in organic fertilizer production in a circular economy context. Therefore the lack of regulation and control over antibiotics occurrence should be implemented to avoid a misuse and an increment of antibiotic resistance pressure over the environment and to ensure safety of the feed and food chain.