Toward Harmonization of Performance Criteria for Mycotoxin Screening Methods: The EU Perspective

Screening methods are defined as methods that are used to detect the presence of a substance or class of substances at the level of interest. These methods must have the capability of high sample throughput when being used to screen large numbers of samples for potential noncompliant results. Before using a screening method for practical applications, its fitness for the intended purpose needs to be demonstrated. This is normally achieved by conducting a validation study, comparing method performance against predefined criteria. Official guidelines recently established by the European Union for the evaluation of fitness-for-purpose performance parameters of screening methods to be used for the detection of mycotoxins in foods are presented and discussed herein. Practical applications of this evaluation scheme for single- and interlaboratory validation studies, as well as relevant information on screening method performances are reviewed, with emphasis on the impact of mycotoxin contamination in real samples on the fitness-for-purpose of the screening test. Lastly, validation follow-up is discussed in terms of extension of the scope of the method (increasing the range of application in terms of mycotoxin/matrix combinations), method implementation and verification, and evaluation of the method's applicability to modified mycotoxins.