Environmental Contaminants

Sascha Usenko, Ph.D.


Dr. Sascha Usenko's, assistant professor of environmental science, current research on whale earwax builds on his Ph.D. research, where he gained expertise reconstructing organic contaminant profiles in sediment cores. He obtained a bachelor's degree in environmental science and a doctorate degree in analytical chemistry from Oregon State University.

Using a wide range of analytical techniques such as pressurized liquid extraction and GC/MS, he reconstructed more than 280 contaminant profiles for 14 national parks throughout the western United States. Now using similar analytical techniques, his laboratory has developed the ability to reconstruct organic contaminant and mercury profiles for an individual whale using its laminated earwax plug. This research is being funded by a Marine Mammal Commission grant, which he was the co-principal investigator with Dr. Stephen Trumble.

As an analytical and environmental chemist, he was fascinated to learn that many whale species accumulate layers of wax in their ear canal forming an earplug over their entire lifespan, which is sealed from the external environment.

"I was elated to then learn that scientists in the past have used this waxy matrix as an aging tool, similarly to counting tree rings," Usenko said. "Then the question arose, could earwax plugs chronologically archive fat-soluble chemicals, such as man-made pollutants?"

Over the past two years, Usenko's laboratory has been working on developing the analytical methods capable of answering that very question.

"The answer is an emphatic yes! I am happy to report we now have the analytical methods capable of measuring organic contaminants, mercury, and now hormones in whale earwax," Usenko said. "Utilizing these methods, we can now reconstruct lifetime chemical profiles (i.e. from birth to death) for an individual whale for the first time."

To interview Dr. Usenko, contact Tonya B. Lewis, at (254) 710-4656, or the Office of Media Communications at (254) 710-1961.

Additional Links:

The Usenko Laboratory

Dr. Usenko's department webpage