(At Step 3 of the Procedure)
1. INTRODUCTION
1.1 Scope
The analytical methods listed are those which may, from practical experience of the Codex Committee on Pesticide Residues, be considered for the determination of pesticide residues for regulatory purposes. The list, given in par.2, is not exhaustive and methods not mentioned in the list can also be applied, provided that they can be shown to produce valid results, by the analyst using them.
1.2 Criteria for the selection of analytical methods
Whenever possible, the CCPR used the following criteria when selecting analytical methods:
i. Available through national or international standards organizations, books, manuals, open literature, the internet;Preference was given to gas chromatography or high performance liquid chromatography as the separation step for the methods. Under certain conditions however, screening methods as defined in the Guidelines on Good Practice in Residue Analysis may be applicable. Screening methods are indicated in the list.ii. collaboratively studied or known to have been validated in a number of laboratories. For single laboratory validated methods validation must have taken place according Guidelines on Good Practice in Pesticide Residue Analysis as a minimum;
iii. capable of determining more than one residue, i.e. multi-residue methods;
iv. suitable for as many commodities as possible at concentrations at or below the specified MRLs;
v. applicable in a regulatory laboratory equipped with generally available analytical instrumentation.
1.3 Application of methods
Before applying the methods it will always be necessary to validate the method and to demonstrate the competence of the analyst using it. T here is a further need for regular verification of the performance of the method during use. Validation and performance verification are described in the Guidelines on Good Practice in Residue Analysis.
