Lower limit of quantitation

{
  "id": "MLC-T-ENV-016139",
  "term": "Lower limit of quantitation",
  "field": "Environment",
  "term_source": "Lower Limit of Quantitation",
  "definition": "1. The lowest concentration at which the laboratory has demonstrated target analytes can be reliably measured and reported with a certain degree of confidence. The LLOQ must be greater than or equal to the lowest point in the calibration curve. The laboratory shall establish the LLOQ at concentrations where both quantitative and qualitative requirements can consistently be met. The laboratory shall verify the LLOQ at least annually, and whenever significant changes are made to the preparation and/or analytical procedure, to demonstrate quantitation capabillity at lower analyte concentration levels. The verification is performed by spiking a clean control material (e.g., reagent water, solvent blanks, Ottawa sand, diatomaceous earth, etc.) or a representative sample matrix, free of target compounds, at the LLOQ and processing through all preparation and determinative steps of the method. Optimally, the LLOQ should be less than the desired decision level or regulatory action level based on the stated DQOs.\n\n2. Lowest concentration at which the laboratory has demonstrated target analytes can be reliably measured and reported with a certain degree of confidence. The LLOQ must be greater than or equal to the lowest point in the calibration curve. The laboratory shall establish the LLOQ at concentrations where both quantitative and qualitative requirements can consistently be met. The laboratory shall verify the LLOQ at least annually, and whenever significant changes are made to the preparation and/or analytical procedure, to demonstrate quantitation capabillity at lower analyte concentration levels. The verification is performed by spiking a clean control material (e.g., reagent water, solvent blanks, Ottawa sand, diatomaceous earth, etc.) or a representative sample matrix, free of target compounds, at the LLOQ and processing through all preparation and determinative steps of the method. Optimally, the LLOQ should be less than the desired decision level or regulatory action level based on the stated DQOs.Forum on Environmental Measurements (FEM) Glossary]",
  "abbreviation": "LLOQ",
  "subject": "Measurements",
  "references": [
    "Forum on Environmental Measurements (FEM) Glossary",
    "EPA EV-Measurements-Laboratory Measurements"
  ],
  "url": "https://mlchart.com/terminology/environment/lower-limit-of-quantitation/"
}