Even the worst chemical compounds poisoning our environment and our bodies all have one thing in common: they are made up of common chemicals that pose little or no danger to us. What if we could take these harmful compounds apart, removing pieces like we would to deconstruct a LEGO creation, and turn them from a toxic compound into a harmless one?
This is the goal of a new research project funded by a three-year, $261,000 National Science Foundation grant led by Western Washington University Professor of Chemistry John Gilbertson and Associate Professor of Chemistry Tim Kowalczyk, as well as their students, specifically around a common group of compounds called nitrates.
“Nitrogen oxides such as nitrates exist naturally, and as their name suggests, they are a compound with a main building block of nitrogen,” Gilbertson said. “Unfortunately, humanity is introducing large amounts of nitrates into the ecosystem through their use of nitrogen-based fertilizers, for example. Plants love them. But one of their most harmful impacts is when large amounts of nitrates enter freshwater or estuarine ecosystems.”
Nitrate loading into these environments results in massive blooms of the tiny plants that live in the water column, such as algae, triggering toxic red tides or catastrophic growth that chokes waterways – compounded when the algae dies and decays, robbing the water column of oxygen and resulting in fish kills or rendering the shellfish living in huge swathes of waterways poisonous and unable to be harvested.
The research that Gilbertson and his students are working on involves the development of specific compounds that provoke a reaction in a molecule such as nitrate to convert it to something less harmful. A common example of this chemical concept exists in the cars we all drive.
“Our cars’ catalytic converters pull apart the toxic nitrogen oxides in automotive exhaust. Through the gas’ interaction with a catalyst, the exhaust is broken into its component parts of nitrogen and oxygen,” he said. “It all comes down to that reaction that the catalyst can provoke.”
However, unlike the method happening in our cars’ exhaust systems, nitrate is not a gas -- but the research group at Western is attempting to apply similar concepts to breaking these compounds down. The desired end result is the same – converting the nitrogen oxides into nonharmful, or even useful compounds.
Gilbertson works with WWU Associate Professor of Chemistry Tim Kowalczyk, a computational chemist, to help model these proposed compounds and how they might be constructed, in order to find target compounds to experiment on. Then Gilbertson and his students take to the lab to try and catalyze the reactions in question.
Walker Marks, a former Western undergraduate from Tonasket who is now a WWU graduate student working on his master’s degree in Gilbertson’s lab, said it is fascinating to be doing work that could have such a practical, positive outcome for the environment.
Western is a really good place to be a chemical researcher, and the department allows students the opportunity to run their own projects, even at the undergraduate level.
“Our work is heavily influenced by what we observe in natural systems and how they handle these pollutants, and usually involves denitrifying bacteria and their associated enzymes,” said Marks. “Western is a really good place to be a chemical researcher, and the department allows students the opportunity to run their own projects, even at the undergraduate level. That's not an experience that is very common for young chemists, such as those at PhD-granting universities.”
Megan Deshaye of Olympia, like Marks a former WWU undergrad who is now preparing to defend her master’s thesis at Western, worked in Kowalczyk’s lab to run many of the computational models for the different structures in the paper.
“It was an excellent interdisciplinary experience and I really enjoyed collaborating with a group whose work was so new to me,” she said. “I enjoyed it so much that I opted to take an inorganic class with Dr. Gilbertson the following year.”
The nitrate research of Gilbertson and Marks has been well received, and last summer the pair published a new paper on their findings in Chemical Communications, a journal of the Royal Society of Chemistry.
“Working with students like Walker and Megan is one of the things that makes teaching at Western so special,” said Gilbertson. “And this new grant will allow us to hire three undergraduate researchers a year to continue that same type of research work.”
For more information about this new NSF grant, contact John Gilbertson at firstname.lastname@example.org.