Water research legacy lives on at the University of North Texas
In 1935, J.K.G. "Doc" Silvey arrived at the University of North Texas and began researching why water from the tap tasted differently at different times. Silvey's work laid the foundation for three-quarters of a century of groundbreaking water-related research at the university. Once UNT's earliest environmental scientists discovered that conventional pollutants, like nitrogen and phosphorus, accounted for the changing characteristics of tap water, researchers began investigating the effect on water of more exotic chemicals such as pesticides and heavy metals.
Over the years, UNT scientists have developed an understanding of the compounds and processes that can damage water quality, allowing them to lead restoration and conservation efforts across Texas. Today, researchers in UNT's Institute of Applied Science continue to push boundaries in the fields of aquatic toxicology, ecosystem restoration and aquatic ecology, while others examine the importance of water through disciplines such as geography, philosophy and film.
Thousands of different chemical compounds enter America's waterways every day. The combined effects of 300 million people flushing or washing chemicals down the drain can significantly impact water quality. Duane Huggett, assistant professor of biology, studies the impacts of pharmaceuticals and other synthetic compounds on the health of aquatic organisms. With a grant from the Environmental Protection Agency, he is working to validate a new study design assessing the effects of endocrine disruptors, such as the pesticides lindane and vinclozolin, on mysid shrimp survival, growth and reproduction. Endocrine disruptors have possible links to breast cancer and lowered sperm counts in humans.
"Our findings indicate that endocrine disruption caused by the toxicants can lead to reduced reproductive capabilities in the mysids," Huggett says, which, due to their role in the food chain, "could have major environmental and economic implications."
His team also is working to improve the efficiency of bioconcentration testing in fish. Testing the effects of one compound requires hundreds of organisms and more than two months of measurements. Postdoctoral researcher David Hala is working on a grant from the European Chemical Industry Council and the International Life Sciences Institute to develop an abbreviated method integrating computational modeling with experimentation.
"It would significantly reduce the numbers of fish and the time and money it takes to complete such studies," Hala says. "We are working toward the future of toxicology."
Aaron Roberts, assistant professor of biology, also studies the effects of toxins on aquatic organisms. His team is conducting oil toxicity testing with fish and invertebrates in support of the Natural Resource Damage Assessment of the DeepWater Horizon oil spill. The testing is a collaborative effort of Stratus Consulting, the National Oceanic and Atmospheric Administration, UNT and several other academic institutions.
"Aquatic organisms are an important natural resource and serve as the 'canaries in the coal mine' for pollutants in our waterways," Roberts says. "Understanding how pollutants affect them provides better protection of economically and ecologically important species and an early warning system for pollutants that might pose a risk to human health."
Roberts is working with Texas Christian University researchers to study the impact of mercury contamination on fish. His laboratory participated in a focused study of Caddo Lake, where the team discovered that spotted gar have liver damage that appears to be related to mercury. The study represents some of the first direct evidence that mercury negatively impacts the health of fish, with important implications across the food chain.
Samuel Atkinson, Regents Professor and director of UNT's Institute of Applied Science, uses the knowledge he and fellow scientists have gathered to oversee a number of conservation and restoration projects. Institute researchers work with the U.S. Army Corps of Engineers at the Lewisville Aquatic Ecosystem Research Facility to study the impact of nuisance plants that clog waterways and are associated with damage from pollutants.
Atkinson, with Mike Smart, Dian Smith and Lynde Dodd, received grants to begin restoring the ecosystems in various Texas lakes. Their studies of lakes and rivers across the state have been funded by the National Science Foundation, Texas Parks and Wildlife, the EPA and several Texas municipalities.
"Many aquatic ecosystems across the nation have been adversely altered by human activities," Atkinson says. "Once the sources of the impacts are discovered and understood, we can develop techniques to restore these valuable resources."
Other researchers focus on the responses of aquatic ecosystems to environmental change. David Hoeinghaus, Tom La Point and science education expert Ruthanne "Rudi" Thompson in biology with Miguel Acevedo in electrical engineering and geography were lead researchers on a National Science Foundation grant focused on aquatic ecosystem and water sustainability. The collaborative looked at the upper Trinity River basin as a model system facing rapid urbanization and increased reliance on surface water.
Hoeinghaus, an ecologist who does much of his work in Brazil, says the questions he examines about ecological communities and ecosystems could be researched in forested landscapes or other settings, but aquatic systems provide unique diversity.
"There are things you may not recognize when you look at the surface," he says. "But when you go down to a virgin tropical river, pull a net and find 300 species, it's an eye opening experience."
UNT's emphasis on conservation also has taken root at the southernmost tip of the Americas. Students and faculty research and participate in education and conservation efforts in Chile at the Cape Horn Biosphere Reserve as part of UNT's Sub-Antarctic Ecosystems and Biocultural Conservation program.
Under the direction of co-director James Kennedy, Regents Professor of biological sciences, Tamara Contador researched how the lifecycles of freshwater insects of the Róbalo River differ from those in the Northern Hemisphere.
"Insects are an indicator of water quality and they keep the water clean," says Contador, who earned her doctorate in December and is an instructor for the program. "The Róbalo River has some of the cleanest fresh waters in the world, so we hope to use it as a comparison site for impacted bodies of water elsewhere."