AOAC GFA Stakeholder Program Meeting Book (March 17, 2022)

Terms and Definitions: Highlights

• Sample : A small portion or quantity taken from a population or lot that is ideally a representative selection of the whole. Samples are taken from lots for purposes of scientific examination and analysis and are intended to provide characteristic information about the population, generally by applying statistical calculations. [ISO 3534-1:1993] • Laboratory sample : Sample as prepared for sending to/received by the laboratory and intended for inspection or testing [ISO 7002:1986] • Analytical sample : The material from which the test portion is selected (after grinding/homogenization if necessary • Test portion : A fraction of a sample, all of which is intended for analysis. There are cases (liquid products, analysis of symptoms, etc.) where the laboratory sample is also the test sample. [ISO 21572]

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Terms and Definitions: Highlights

• Limit of detection (LOD) : The lowest concentration or mass of analyte in a test sample that can be distinguished from a true blank sample at a specified probability level (ISO 5725-1:1994). • Limit of quantification (LOQ) : The lowest level of analyte in a test sample that can be reasonably quantified at a specified level of precision (ISO 5725-1:1994).

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