2019 Vet Drug Residues ERP - Review Book

6. Based on the supporting information, what are the cons/weaknesses of the method?

1. The method appears to monitor the parent drugs for all the antibiotics involved with no indication that the marker residues that had been identified for regulatory monitoring by International organizations were being monitored. [Seek clarification from method authors] 2. For the multi-residue method containing 105 compounds, it appears that there were some vet drugs for which the appropriate marker residues were not monitored. 3. These included – enrofloxacin as ciprofloxacin, febantel as oxfendazole sulphone, flubendazole as 2-amino 1H-benzimidazol-5-yl-(4- fluorophenyl) methanone; florfenicol as florfenicol amine, fenbendazole as oxfendazole sulphone and fenbendazole sulfoxide; nicarbazin as dinitrocarbanilide (DNC), oxfendazole as oxfendazole sulphone; phenylbutazone as oxyphenbutazone, spiramycin as a mix of spiromycin and neo-spiramycin, carprofen as the glucoronidase; Triclabendazole as ketotriclabendazole. 4. Monitoring ceftiofur as ceftiofur (should be monitored as desfuroylceftifur) 5. Chromatographic retention times provided but no Ionization parameters for the 105 compound method;

7. Any general comments about the method?

Check with method authors to ensure that the appropriate marker residues are being monitored and not merely the parent drugs for convenience.

V. Final Recommendation Do you recommend this method be adopted as a First Action and published in the Official Methods of Analysis of AOAC INTERNATIONAL? Please specify rationale.

Recommend first action.

If possible, the authors should include in a Table the recommended MARKER RESIDUE that should be monitored for these APPROVED veterinary drugs in these food matrices.