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24 May 2012

Answer to Question #4059 Submitted to "Ask the Experts"

Category: Radiation Basics — Radionuclides

The following question was answered by an expert in the appropriate field:

What are the biological and physical half-lives of ^99mTc DTPA (diethylenetriaminepentaacetic acid)?

International Commission on Radiation Protection Publication 53 (ICRP, Pergamon Press 1988) description says that ^99mTc DTPA clears from the whole body in two fractions: 99% with a 1.67-h biological half-time and 1% with a seven-day biological half-time. The physical half-life of ^99mTc is close to 6-h.

Michael G. Stabin, PhD, CHP

Answer posted on 5 November 2004. The information and material posted on this website is intended as general reference information only. Specific facts and circumstances may alter the concepts and applications of materials and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice specific to whatever facts and circumstances are presented in any given situation. Answers are correct at the time they are posted on the Website. Be advised that over time, some requirements could change, new data could be made available, or Internet links could change. For answers that have been posted for several months or longer, please check the current status of the posted information prior to using the responses for specific applications.