Cereals and derived products may contain different groups of contaminants, including pesticide residues and mycotoxins, for which maximum limits have been established by the EU legislation. For enforcement purposes it is essential the availability of precise and reliable analytical methods applicable at the regulatory levels. Furthermore a current trend in chemical food safety control is represented by the efforts to integrate analyses of various groups of food contaminants into high-throughput methods with one common sample preparation and a single final determination. Due to increasing availability of analytical equipments enabling high sensitivity and selectivity, contaminants detection and determination by mass spectrometry plays an important role in this field, and sample preparation can become the most challenging task. Several strategies based on either traditional clean up devices or innovative systems are continuously proposed and evaluated for their contribution in the achievement of satisfactory method performances, including acceptable matrix effects. The higher is the selectivity of the sample preparation protocol the lower is the number of analytes that can be included in the method that provides in turn better performances for the specific analytes. On the contrary, less selective clean up strategies, allowing to analyze a larger number of mycotoxins and/or pesticide residues require higher instrumental technical specifications (selectivity and sensitivity) to achieve satisfactory method performances. Despite the large number of currently available LC-MS(/MS) methods for multiple contaminant determination in foods, most of them proved to be suitable for semi-quantitative or screening purposes only due to the lack of sufficient validation efforts. Acceptability criteria for analytical methods are reported in the Commission Regulation 401/2006 for each regulated mycotoxin, whereas criteria for pesticide analysis are reported in the Document SANCO/12495/2013. Another effective procedure for quality assurance and performance verification of the chemical analysis in food control laboratories is represented by Proficiency testing (PT), providing a clear and a straightforward way of evaluating the accuracy (trueness and precision) of results obtained by different laboratories. The application of advanced MS approaches for mycotoxin and/or pesticide control along the cereal food chain will be presented. In particular the following methods will be described, with emphasis to validation aspects according to European standards, and application to real samples: - a method for the simultaneous determination of aflatoxins, ochratoxin A, fumonisins, trichothecenes (including glucosyl and acetyl derivatives) and zearalenone in cereals and derived products based on multi-antibody immunoaffinity column clean up and LC-MS/MS detection; - a method for the simultaneous determination of aflatoxins, ochratoxin A, trichothecenes and zearalenone in wheat, by direct injection in LC-MS/MS without clean up; - a combined LC-MS/MS - GC-MS/MS method for the simultaneous determination of a total of 620 pesticide residues in wheat; - a generic procedure for the simultaneous determination of mycotoxins and pesticides in wheat based on QuEChERS extraction and LC-MS/MS detection. Performances of the above methods applied by the Authors laboratories in an international Proficiency Testing will be reported, together with some general conclusions on the state-of-art of currently used LC-MS(/MS) multi-mycotoxin methods. The Proficiency Testing was organized by ISPA-CNR in 2014 in the framework of the Italian project S.I.Mi.S.A. (PON02_00186_3417512) and promoted by the MoniQA Association (www.moniqa.org) to check, next to the laboratory performance, the state-of-art of currently used multi-mycotoxin methods and their implementation in public and private food control laboratories from several countries worldwide.
MS-Based methods and proficiency tested materials for reliable analysis of food contaminants: mycotoxins and pesticides in cereals
A Visconti;
2015
Abstract
Cereals and derived products may contain different groups of contaminants, including pesticide residues and mycotoxins, for which maximum limits have been established by the EU legislation. For enforcement purposes it is essential the availability of precise and reliable analytical methods applicable at the regulatory levels. Furthermore a current trend in chemical food safety control is represented by the efforts to integrate analyses of various groups of food contaminants into high-throughput methods with one common sample preparation and a single final determination. Due to increasing availability of analytical equipments enabling high sensitivity and selectivity, contaminants detection and determination by mass spectrometry plays an important role in this field, and sample preparation can become the most challenging task. Several strategies based on either traditional clean up devices or innovative systems are continuously proposed and evaluated for their contribution in the achievement of satisfactory method performances, including acceptable matrix effects. The higher is the selectivity of the sample preparation protocol the lower is the number of analytes that can be included in the method that provides in turn better performances for the specific analytes. On the contrary, less selective clean up strategies, allowing to analyze a larger number of mycotoxins and/or pesticide residues require higher instrumental technical specifications (selectivity and sensitivity) to achieve satisfactory method performances. Despite the large number of currently available LC-MS(/MS) methods for multiple contaminant determination in foods, most of them proved to be suitable for semi-quantitative or screening purposes only due to the lack of sufficient validation efforts. Acceptability criteria for analytical methods are reported in the Commission Regulation 401/2006 for each regulated mycotoxin, whereas criteria for pesticide analysis are reported in the Document SANCO/12495/2013. Another effective procedure for quality assurance and performance verification of the chemical analysis in food control laboratories is represented by Proficiency testing (PT), providing a clear and a straightforward way of evaluating the accuracy (trueness and precision) of results obtained by different laboratories. The application of advanced MS approaches for mycotoxin and/or pesticide control along the cereal food chain will be presented. In particular the following methods will be described, with emphasis to validation aspects according to European standards, and application to real samples: - a method for the simultaneous determination of aflatoxins, ochratoxin A, fumonisins, trichothecenes (including glucosyl and acetyl derivatives) and zearalenone in cereals and derived products based on multi-antibody immunoaffinity column clean up and LC-MS/MS detection; - a method for the simultaneous determination of aflatoxins, ochratoxin A, trichothecenes and zearalenone in wheat, by direct injection in LC-MS/MS without clean up; - a combined LC-MS/MS - GC-MS/MS method for the simultaneous determination of a total of 620 pesticide residues in wheat; - a generic procedure for the simultaneous determination of mycotoxins and pesticides in wheat based on QuEChERS extraction and LC-MS/MS detection. Performances of the above methods applied by the Authors laboratories in an international Proficiency Testing will be reported, together with some general conclusions on the state-of-art of currently used LC-MS(/MS) multi-mycotoxin methods. The Proficiency Testing was organized by ISPA-CNR in 2014 in the framework of the Italian project S.I.Mi.S.A. (PON02_00186_3417512) and promoted by the MoniQA Association (www.moniqa.org) to check, next to the laboratory performance, the state-of-art of currently used multi-mycotoxin methods and their implementation in public and private food control laboratories from several countries worldwide.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
