Professor Santschi Uses Molecules to See the Big Picture of Nuclear Waste

By Patrick Temperilli
Academic Affairs

Texas A&M University at Galveston's Regents Professor Dr. Peter Santschi, along with his research team, has recently established a ground-breaking method with which to trace radioactive particles in the environment.  The studies, which took place over the past decade, could have a profound impact on the future viability and risk mitigation of nuclear energy.

Dr. Peter Santschi with his research team

Science is all about asking questions.  According to Santschi, the problem in tracking nuclear waste, is that the prediction models often ignore the changing properties of the radioactive molecules and disregard how potentially dangerous waste radioisotopes interact with the environment.  What sets his latest studies apart is that they started asking the right questions.

"You couldn't get the right answer because each chemical species has a different behavior, so the more species you have, the more complicated the question becomes" says Santschi, breaking down the subject further.  "If you work at concentrations [of radioactive molecules] that are too high, then you don't see the same behavior as at those smaller concentrations that occur in the environment.  You also have to consider all the interactions with bacteria, algae, and fungi, which have enzymes that can drive the transformation in those chemical species."

Dr. Santschi's research team, which consists of TAMUG research scientists Chen Xu, Saijin Zhang, Kathleen Schwehr, Peng Lin, and Russell Grandbois, as well as a host of other collaborators from both the United States and Japan, began looking specifically at radioactive iodine molecules, called radioiodine, and their interactions with organic molecules.  Santschi has had to incorporate elements of both environmental radiochemistry and environmental organic chemistry as radioiodine molecules in general are tricky; they take numerous forms and have a propensity to latch onto organic molecules.  These complications create a myriad of challenges to any sort of tracing effort.
As Dr. Santschi says, "The details of analytical aspects are more important than people often assume."

In order to find the solutions, Santschi and his team developed a new approach in tracing radioactive molecules like iodine-129, which is prone to absorption in the environment due to its low mobility, and long term impact due to its half-life of 16 million years.  Using a combination of Gas Chromatography/Mass Spectrometry (GC-MS) and other techniques, the team was able to create a breakthrough in detecting radioiodine at the low concentration levels that better represent those in the environment.

Santschi's work allows for a clearer understanding of the potential effects of nuclear disasters.  "Radioisotopes are no different from any other pollutant.  Even though every pollutant has different characteristics, there are some generalities.  You can make some predictions depending on the categories of the pollutants."  Despite the fact that much of the research on this project took place on land, Santschi insists that its results apply to multiple environments.  "You can have insights working on land and then transfer the new knowledge or skills to the ocean, and vice versa.  Whatever pollutants you have on land will eventually end up in the ocean.  It's only a matter of time."

Looking ahead at the future of nuclear energy, Santschi is vexed.  "The future doesn't look good in the U.S., or in Europe.  The pendulum has swung and now people are afraid. We are schizophrenic about it" says Santschi.  "We are using [nuclear power plants], but we don't want the waste sites.  So we store the waste onsite, which is where the reactor is.  This is the worst possible outcome because then they are prone to accidents, which is what you had at Fukushima."

But in an age where countries are desperately seeking alternative energy sources, Dr. Santschi's team's newfound techniques will be a great asset moving forward by clarifying the potential effects of nuclear disasters and/or waste disposal.  The timing couldn't be better, as industrializing countries around the world increasingly turn to nuclear power in their search for energy solutions.