Analytical methods legislative requirements

In summary, the purpose of any validated analytic method is to obtain consistent, reliable, and accurate measurements. The results from method validation can be used to judge the quality, reliability, and consistency of analytic results, which is an integral part of any good analytic practice and the base of which is supported by the identification and quantification of active substances, studies of their fate and behavior, and studies of their residue. Validation of analytic methods is required by actual EU legislative framework and has received considerable attention in the literature from industrial committees and regulatory agencies. 

Consideration of the above requirements confirms that in future all methods must be fully validated if at all possible, i.e. have been subjected to a collaborative trial conforming to an internationally recognised protocol. In addition this, as described above, is now a legislative requirement in the food sector of the European Union. The concept of the valid analytical method in the food sector, and its requirements, is described below. 

European Community Commission Regulation No. 2701/94 (21) states that the maximum residue level (MRL) for all substances belonging to the tetracycline group is the sum of the residues of all substances within the group. This legislative requirement necessitates the development and use of analytical methods capable of simultaneously detecting residues of more than one tetracycline. The MRLs for combined tetracycline residues are 600 yug/kg, 100 /U,g/kg, and 100 /u,g/kg in kidney, muscle, and milk, respectively (22). 

Due to the demand for reliable and comparable methods, performance requirements have been established at a national and international level for implementation of official methods, e.g. by European legislation, by the CEN or the Association of the Analytical Communities (AOAC) International, and worldwide by Codex Alimen-tarius (CAC). Thus any method proposed to be used for official purposes must be validated in a collaborative trial study, resulting in defined method performance characteristics [4], The framework for the design and conduct of such collaborative trial studies, as well as the statistical evaluation, are also defined in appropriate protocols [5]. Any method that has been successfully validated according to these protocols can be recognised as an official method for use in legal cases or for international trade control purposes. 

Vinyl chloride is a gas at ambient temperature and the official EC analytical methods for both determinations use headspace GC with a flame ionization detector (FID). Where a determination exceeds the legislation limit, confirmation is required with head-space GC using either a different chromatography column, or a different detector, or with the gas chromatograph coupled to a mass spectrometer. 

PAs cause veno-occlusive disease of the liver after significant consumption and are associated with other ill effects. Comprehensive knowledge of the occurrence of PAs in food and feed is required for the calculation of exposure affecting animals and humans, and to support legislation formulate advice to consumers. Current research into improving or replacing older analytical methods has been prompted by advice to consumers from Australian and New Zealand authorities related to contaminated honey, and by requests from the European Commission via the European Eood Safety Authority (EESA). 

A substantial number of research articles can be found in analytical literature about cosmetic analysis in which different analytical procedures are proposed to determine a great many ingredients in cosmetics. Despite this, more research in this field is necessary because the proposed methods are still insufficienL Consequently, researchers in the field of analytical chanistry have to make an effort to extend and modernize the existing methods and develop new analytical methods, which can fulfil the requirements of legislation. Therefore... 

REQUIREMENTS IN ANALYTIC METHODS TO FULFILL THE ACTUAL EUROPEAN LEGISLATIVE FRAMEWORK... 

As for the detection techniques, MS has become one of the most important techniques in analytic chemistry for the study of biopesticides. In fact, it has almost displaced other detection devices in the development of analytic methods properly validated for the study of biopesticides (Table 3). The combination of chromatographic techniques and an MS detector appears to be a suitable approach to satisfy the actual EU legislative requirements in terms of sensitivity, selectivity, and peak-assignment certainty for the rapid determination of analytes at low concentrations in complex matrices. A mass spectrometer is an analytic instrument that can separate charged molecules according to their mass-to-charge ratio (miz). There are three main parts/criti-cal components of a mass spectrometer the ion source, the mass analyzer, and the detector [131]. 

LC-LC is applied to environmental samples with two major aims, i.e. to determine a single analyte and to determine a group of analytes (by the multrresidue methods) at the low levels required by legislation in both cases. Some examples of these are discussed below. In addition, some applications for the particular case of SPE-LC, will also be described. 

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