Codex Alimentarius analytical methods

CX/MAS 01/8 (2001), Codex Alimentarius Commission, Codex Committee on Methods of Analysis and Sampling (FAO/WHO), Measurement uncertainty. Relationship between the analytical result, the measurement uncertainty and the specification in Codex standards, agenda item 4a of the 23rd session, Budapest, Hungary, Feb. 26-Mar. 2, 2001. 

The discipline of analytical chemistry is wide and catholic. It is often difficult for a food chemist to understand the purist concerns of a process control chemist in a pharmaceutical company. The former deals with a complex and variable matrix with many standard analytical methods prescribed by Codex Alimentarius, for which comparability is achieved by strict adherence to the method, and the concept of a true result is of passing interest. Pharmaceuticals, in contrast, have a well-defined matrix, the excipients, and a well-defined analyte (the active) at a concentration that is, in theory, already known. A 100-mg tablet of aspirin, for example, is likely to contain close to 100 mg aspirin, and the analytical methods can be set up on that premise. Some analytical methods are more stable than others, and thus the need to check calibrations is less pressing. Recovery is an issue for many analyses of environmental samples, as is speciation. Any analysis that must... 

Anklam et al. [7] as well as Ahmed [8] recently published a comprehensive overview of different PCR assays that have been published in the literature. The authors tried to include performance data adding to the value of the review articles. The validation of PCR methods and thus the establishment of such performance criteria is still the subject of much debate. H bner et al. [9] suggested an approach for the validation of PCR assays. In general, it is currently the view of most researchers that validation of a PCR assay should not differ essentially from the validation of other analytical methods. Thus, all principles outlined in the ISO standard 17025 General requirements for the competence of testing and calibration laboratories, ISO standard 5725 Accuracy (trueness and precision) of measurement methods and results as well as the principles as laid down by Codex Alimentarius (http //www.co-dexalimentarius.net), are applicable to PCR. 

Selected references. These procedures were adapted essentially from AO AC Official Methods of Analysis [7s], The Society for Analytical Chemistry, Official, Standardised and Recommended Methods of Analysis [8g], UK Ministry of Agriculture Technical Bulletin 27 [21], Subcommittee on Procedures of the Chemistry Task Force of the (US) National Shellfish Sanitation Program [24] and Joint FAO/WHO Food Standards Programme, Codex Alimentarius Commission [125b]. Other pertinent references are 30i, 37a, 38d, 39d and 128b. 

The reported composition of regular sunflower oil has changed with adjustments of analytical methods and the samples considered. This is reflected in the variation ranges approved successively by the Codex Alimentarius Comission. The values approved in 1981 and 1993 (21) are compiled in Table 2, as well as the current... 

In recent years, demand for better methods for phycotoxin management has emerged as a resnlt of increasing pnblic concerns on health risks, action levels, method specificity, and performance. These technical issnes have become matters of discussion in international bodies such as the EU Commission and the Codex Alimentarius. As a result, new analytical and functional approaches for phycotoxins have been developed. In particular, efforts have been undertaken to design in vitro methods alternative to the current MBA for paralytic shellfish poison. ... 

There are two sources of information from the CAC that provide guidance on the validation of analytical methods. General guidance on method validation, including single-laboratory method validation, may be found in the CAC Procedural Manual.This is supplemented by Codex Alimentarius Commission guidelines, a number of which have been adopted from harmonized guidelines previously developed by independent international scientific... 

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