Term: effective half life
https://doi.org/10.1351/goldbook.E01894

Definition:
For a radioactive substance, the time required for the amount of that substance in a biological system to be reduced to one half of its value by both radioactive decay and biological processes, when the rate of removal is approximately exponential.

Related Terms:
1) radioactive (http://doi.org/10.1351/goldbook.R05077).
2) radioactive decay (http://doi.org/10.1351/goldbook.R05083).

Source: PAC, 1994, 66, 2513. 'Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)' on page 2520 (https://doi.org/10.1351/pac199466122513)

Citation: 'effective half life' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.E01894

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