MCPD-02 Reviewer Forms (July 19, 2018)

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Reviewer 5 Expert Review Panel for Infant Formula and Adult Nutrition (MCPD)

Evaluation of Method MCPD-02 (SGS)

Title: 2-Monochloropropanediol (2-MCPD), 3-Monochloropronaediol (3-MCPD) and Glycidol in Infant and Adult/Pediatric Nutritional Formula

Author: Jan Kuhlmann

Reviewer Name:

Summary of Method: A heat and sonicated assisted liquid-liquid extraction with MTBE and methanol is used to extract the bound MCPD and bound glycidol from powdered formula. The organic layer undergoes base catalyzed hydrolysis, is derivatized with PBA, and analyzed by GC-MS/MS. The liquid layer is derivatized with PBA and analyzed by GC-MS. Liquid samples are extracted with the Rose-Gottlieb, with the aqueous layer and organic layers then treated identically to powdered samples.

Method Scope/Applicability: Powdered and liquid infant and adult nutritionals

General comments about the method: Couples a well validated fat extraction method for infant formula to a well validated, collaboratively studied detection method. There is also extensive inter-method comparison with other validated methods, which adds confidence to the accuracy of results.

Method Clarity: The method is clear and provides sufficient detail to ensure it can be reproduced. Also provides complete detail on the equipment conditions and consumable supplies. It might be slightly easier to follow if the steps were individually numbered. Method Safety Concerns: Uses common lab chemicals that require PPE and fume hoods including sodium hydroxide and ethers. Pros/Strengths: • The assay combines the analysis of free and bound in a single extraction. • The use of isotopically labeled standards for all target analytes helps ensure accurate results. • Quantification using widely available GC-MS platform. • Base hydrolysis (as used in AOAC Cd29-13b) is well validated and known not to create or destroy the target analytes. • An extensive inter-laboratory comparison with another validated method adds confidence to the accuracy of results. • Includes a straightforward approach to confirm purity for the isotopically labeled standards. • Includes the possibility of multi-point external calibration.

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