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OMB MEETING MATERIALS

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quality control acceptance criteria, or elimination of steps in the original reference method.

“The validation of standard or collaboratively studied methods should not be taken for granted. The laboratory should make sure the method validation is adequate for the required purpose and that the laboratory personnel can achieve the stated performance criteria. Guidance on the topic of verifying the performance of a standard method is given in ISO 21748” (CITAC/Eurachem Guide to Quality in Analytical Chemistry: An Aid to Accreditation ). Note: There are many documents that provide guidance for method verifications and validations such as, AOAC International How to Meet ISO 17025 Requirements for Method Verification , AOAC Guidelines for Validation of Qualitative Binary Chemical Methods , AOAC Methods Committee Guidelines for Validation of Microbiology Methods for Food and Environmental Surfaces , IUPAC Guidelines for Single-Laboratory Validation of Methods of Analysis , and Definitions and Calculations of HorRat Values from Intralaboratory Data . Note: The AOAC Food Triangle (W. Ikins, et. al., “A Food Matrix Organizational System Applied to Collaborative Studies”, The Referee AOAC International, 17(7) 1,6,7 (1993) , along with the applicable NIST Standard Reference Materials are useful tools for food when determining how many different food matrices should be part of the validation or how to select representative matrices when expanding the scope of an existing method. (Wolf, W.R. & Andrews, K.W. Fresenius J Anal Chem (1995) 352: 73. https://doi.org/10.1007/BF00322300 ). There are limitations in the assumptions inherent in the triangle (e.g., a method for shellfish toxins in oysters does not necessarily work well for scallops and the Food Triangle would not show this). Note: Accuracy can be established by analyzing a suitable Reference Material. It is preferable to work with well characterized, homogenized, and stable materials such as NIST standard reference materials or proficiency test samples; however, an estimation of accuracy can be obtained by spiking test portions. The value of spiking is limited, as it can only be used to determine the accuracy of those stages of the method following the spiking. Accuracy can also be established by comparison with results obtained by a definitive method or other alternative procedures and via interlaboratory comparison studies. CRMs and SRMs can be obtained from variety of sources, including, but not limited to NIST, US Pharmacopeia (USP), British Pharmacopoeia (BP), European Pharmacopoeia (Ph. Eur.), American Herbal Pharmacopoeia (AHP), and PhytoLab. 7.2.2.3 7.3.1 Most laboratories do not collect sample materials outside the laboratory, commonly called “field sampling”. When the laboratory has not been responsible for the initial sampling stage, it may be appropriate to state in the report that the samples were analyzed as received. In cases where the laboratory is required to conduct field sampling of products, they shall comply with established procedures for those programs (e.g., the Meat Importers Council of America North America Guidelines for the Settlement of Fat Claims, GOOD Samples: Guidance on Obtaining Defensible Samples ) and these requirements. There should be a procedure for routinely used sampling methods. Note: Where the laboratory is responsible for sampling, there may be situations where special actions are needed to safeguard the integrity of the test item. “In some circumstances, for example where samples have been taken for legal purposes, the sample may be sealed so that access to the sample is only possible by breaking the seal. Confirmation of the satisfactory condition of the seals will normally then form part of the analytical report” (CITAC/Eurachem Guide to Quality in Analytical Chemistry: An Aid to Accreditation ) and GOOD Samples (AAFCO). 7.2.2.4 (e) The laboratory shall record the laboratory representative who authorized adoption of the method and the date this authorization was granted. 7.3 Sampling

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08/09/2018

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