Optimization and validation of a quick and responsive LC-ESI-MS/MS method to evaluate tetracycline residues in processed animal proteins (PAPs)

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 mu g kg(-1) level. The LC-MS/MS method performances were evaluated in terms of specificity, linearity (25-500 mu g kg(-1)), limit of quantitation (LOQ) (25 mu g kg(-1)), accuracy and precision (CV% < 25%), uncertainty, recovery (80-120%) and ruggedness. 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 (mu g kg(-1)) of tetracyclines in PAPs. PAPs are a powerful product which could be used both as raw materials in feed and in organic fertilizer production in a circular economy context. Therefore, the lack of regulation and control over antibiotic 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.

Automated summary

The aim of this study was to develop and validate a reliable LC-MS/MS method for the determination and quantification of tetracycline residues in PAPs. The LC-MS/MS method exhibited satisfactory performance and can be used as a confirmatory method for the presence of tetracycline residues in PAPs. To ensure safety in the feed and food chain and to avoid misuse and increased antibiotic resistance pressure on the environment, regulation and control over antibiotic occurrence in PAPs should be implemented.