47. The Committee recalled that at its last Session it had considered a paper on establishing routine methods, which had been referred to it by the Codex Committee on Residues of Veterinary Drugs in Foods. The paper explained the difficulties encountered in the area of veterinary drug residue analysis in performing large scale method validation and finding appropriate validated methods. The Committee had proposed to initiate work on in-house method validation, which was approved by the Commission at its 22nd Session. The Delegations of the Netherlands and the United Kingdom had prepared a paper.
48. The Delegation of the Netherlands, in introducing the paper, stated that in the cases of analyses of food moving in trade, inter-laboratory recognition was important. However, where no collaboratively studied methods were available, an in-house method validation could be utilized. Among validation routes, it might be possible to utilize the following routes in an in-house validation scheme and then obtain an externally referenced method yielding acceptable results: (1) calibration using reference materials; and (2) comparison of results achieved with reference methods. It was further stated that an appropriate inter-laboratory study would give important information that might be extrapolated to other analytes and matrices using an in-house validation protocol. However, criteria to be established for such an in-house validation would be different from those for the normal method validation.
49. The Delegation of the United Kingdom reported that IUPAC had initiated work on the development of the Harmonized Guidelines for the In-house Validation of Methods of Analysis last year by the same working group that had finalized a number of protocols and guidelines such as those for collaborative studies and recovery factors. The text contained in Annex 1 of the referenced document was its first draft. He invited participants to comment on the IUPAC Guidelines. He also informed the Committee that there would be an FAO/IAEA/IUPAC Workshop on Method Validation scheduled to be held from 27-29 October 1999 in Budapest, where the Guidelines on In-House Validation would also be considered.
50. The Committee welcomed the paper. However, some delegations stressed that the paper did not and should not discourage performing collaborative studies. The Delegation of France informed the Committee that AFNOR VO3-110 containing an intra-laboratory validation protocol had just been revised and would be published and sent to IUPAC.
51. The Committee decided to request the Netherlands, together with France and the United States, to prepare a paper on the use of information from the proficiency testing studies for the elaboration of characteristics of in-house validated methods for consideration by the Committee at its next session. The Committee agreed that when the next draft of the Harmonized Guidelines became available, it would consider the text to determine if it would be appropriate to recommend it to the Commission for adoption by reference for Codex purposes.
