Mycotoxins The Criteria Approach for Analysis Joerg Stroka

Transcription

1 Mycotoxins The Criteria Approach for Analysis Joerg Stroka Institute for Reference Materials and Measurements (IRMM) Geel, Belgium

2 Future Needs Number of test samples will increase Need for reliable multi-methods Need for reliable simple + rapid methods Need for workable sampling schemes that are all Fit-for-purpose. 2

3 Requirements on a Method User friendly (acceptance by lab technicians) Environmental safe (e.g. Montreal Protocol) As simple as possible (instrumentation) Method performance must be known 3

4 The Situation in Food Control Result = ƒ(sampling, sample preparation & analysis) 4

5 Background Treaty establishing the European Community: Articles 94 and 95 (ex-00 and ex 00a): AND Commission proposing directives for the approximation of such laws, regulations or administrative provisions of the Member States that effect the establishment or function of the common market Considering scientific facts, consumer health and safety will be taken into account at a high level regarded for the harmonisation of the common market. 5

6 Relevant EU Directives and Regulations Directive 85/59 (laying down the framework for sampling and analysis methods on community level) Directive 89/397 (general principles for the official control of foodstuffs) Directive 93/99 (supplement to 89/397/EEC) Directive 98/53 (sampling and analysis methods) Regulation 466/200 (maximum levels for mycotoxins) Regulation 882/2004 (on official controls to ensure compliance with food and feed law) 6

7 Legislative Approaches for Methodology Explicitly specified analytical method e.g. Mercury, humidity or phosphate in animal feed (93/28/EG + 7/393/EEC) e.g. Purity of food additives (8/72/EEC) Quasi horizontal method specifications e.g. Thyreostatica in and hormone residues in milk (93/256/EEC) Horizontal specifications ( Performance based ) Generic specifications for methods intended for monitoring (85/59/EEC) Certain contaminants (mycotoxins) in food (98/53/EEC) 7

8 Requirements - Directive 85/59 Specific to the analyte Accuracy (Trueness & Precision) Precision (RSD r and RSD R from collabor. trial) Limit of detection and quantification Sensitivity Applicability 8

9 Requirements - Directive 85/59 Precision parameters must be obtained according to an internationally accepted protocol: ISO CEN AOAC IUPAC 9

10 Directive 98/53 Applicability: Sampling and analysis methods intended for the official control of certain contaminants in foodstuffs (mycotoxins) General requirements: Method must comply (whenever possible) with Council Directive 85/59/EEC Specific requirements: When no specific method is prescribed at Community level, method must meet certain criteria: max RSD r and RSD R and recovery limits for methods to be used. 0

11 Origin of Parameters Repeatability and Reproducibility (RSD r and RSD R ) are derived from the Horwitz equation: Recommended value: as given by the Horwitz equation Maximum value: 2 x value given by the Horwitz equation W Horwitz (982) Anal Chem 54, 67A-76A Recovery limits are in accordance to the limits given in the CEN Report 3505 about criteria of analytical methods for mycotoxins

12 EU Legislation for Mycotoxins Regulations setting Legislative Limits Directives on Sampling and Methods 2

13 3 EU Legislation for Mycotoxins

14 CEN TC257/WG5 WG5 selects and elaborates methods of analysis for mycotoxins that become European Standards. These Standards can be used for monitoring according to legal limits. 4

15 CEN Technical Report CR 3505 (Criteria of analytical methods of mycotoxins) Definitions for performance parameters (ISO 5725) Performance characteristics values RSD r, RSD R and recovery according to state-of-the-art knowledge and experince (publications from collaborative trial studies in the time from 974 resp ) Aflatoxins, OTA, Patulin, Fumonisins, DON, NIV, Zearalenone, HT-2 and T-2 toxin. 5

16 Data from a Collaborative Trial Max Value (single laboratory) Mean Value (Recovery) Min Value (single laboratory) RSD r = 2.6% ; RSD R = 29.7% ; Rec. = 93% ; HORRAT = 0.9 6

17 Fit-for-purpose? Analyte Matrix Concentration Performance Time and Materials Location and Availability!!! 7

18 Fitness-for-purpose in EU Legislation Background: Limited number of fully validated methods. Solution: Uncertainty function to specify maximum levels of uncertainty. Uf = α 2 ( LOD / 2) + ( C ) 2 Uf = max. standard uncertainty (µg/kg) LOD = Limit of Detection (µg/kg) α = constant (0. 0.2) depending on the concentration (C) C = concentration of interest (µg/kg) 8

19 Fitness-for-purpose Graph LOD 5 µg/kg LOD 0 µg/kg LOD 20 µg/kg LOD 50 µg/kg LOD 00 µg/kg RSD r (%) Concentration of interest (µg/kg) 9

20 2 0 Thank you!