Iodine-129 is a naturally occurring radioactive isotope of iodine with a half-life of 15.7 million years. Although it occurs naturally in the environment, I-129 is formed more abundantly during the fission of uranium and/or plutonium in nuclear energy reactors and the detonation of nuclear weapons. Iodine itself is a non-metallic element, a purplish-black crystalline solid with the rare physical property of sublimation in which the substance can go directly from a solid state to a gaseous state.

I-129 is used as a tracer substance to help determine the impact of nuclear reactions on neighboring surroundings.  I-129 is biophilic and therefore is often concentrated in plants or soils with a high organic content.

I-129 can be used in the identification of very old waters by correlating the amount of natural I-129 or its Xe-129 decay product. It can also be used in the identification of younger bodies of water due to the increased anthropogenic I-129 levels due to nuclear reaction fallout. The following is a list of applications of I-129 analysis:

  • estimation of groundwater residence time
  • tracing of brine migration
  • identification of hydrocarbon source rocks
  • tracing the movement of radioactive contaminant plumes


The radiohalides laboratory at the University of Ottawa is located in the Advanced Research Complex (ARC) where samples are prepared for analysis on the HVE 3MV Tandetron in the Lalonde AMS Facility. The photo on the right shows Iodine extraction from sea water using hexane.

Sample Material Minimum
Sample Size
Canadian Academic Commercial Price
Silver Iodide 2 mg $250 $380
Water (groundwater, seawater, brine) 1 liter $380 $580
Crushed rock (leaching) 10 g $420 $640
Hard rocks, clay, sediments, etc. (caustic fusion) 10 g $460 $700
Hard rocks, clay, sediments, etc. (combustion line) 10 g $480 $730

Discount Schedule: - 5% for batches of 8-15; -10% for batches of 16+ samples
Prices Effective: January 17 2017

Please fill out the sample submission form (link below) and email it back to Monika at  Note, a sample submission form is also required for each individual sample, or group of similar samples.

Sample submission form