Data Series 630
Recovery is the proportion of a target analyte that is quantified by an analytical method and is a primary indicator of the analytical bias of a measurement. Recovery is measured by analysis of quality-control (QC) water samples that have known amounts of target analytes added (“spiked” QC samples). For pesticides, recovery is the measured amount of pesticide in the spiked QC sample expressed as a percentage of the amount spiked, ideally 100 percent. Temporal changes in recovery have the potential to adversely affect time-trend analysis of pesticide concentrations by introducing trends in apparent environmental concentrations that are caused by trends in performance of the analytical method rather than by trends in pesticide use or other environmental conditions.
First posted October 2011
For additional information contact:
See also the Pesticide National Synthesis Web page at
This report supplements USGS Scientific Investigations report 2009–5189:
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Martin, J.D., and Eberle, Michael, 2011, Adjustment of pesticide concentrations for temporal changes in analytical recovery, 1992–2010: U.S. Geological Survey Data Series 630, 11 p., 5 app.
Analytical Method for Pesticides
Measurement of Recovery
Sources, Preparation, and Review of Recovery Data
Temporal Changes in Recovery