Bridging the Gap Between Applied and Pure Science in Environmental Toxicology

In my field of environmental toxicology, I study the impacts of pollution on organisms and the environment. But even within a specific discipline like mine, there is a divide between “applied” and “pure” science. Pure science seeks knowledge for the sake of curiosity and understanding the world around us. For environmental toxicologists, this could mean researching how a chemical in the water causes endocrine disruption or how contaminants in insects impact young birds.

Applied science, on the other hand, uses science to solve real-world issues. It is the practical application of scientific knowledge to build technologies, address problems, or create products. In toxicology, this usually involves conducting an experiment to inform management, industry, or policy decisions. For example, if there were a chemical spill and the state wanted to know how bad it was, scientists might check fish for tumors. Likewise, if an industry wanted to see if a chemical was safe to distribute in the environment, they would conduct applied science experiments.

As an aspiring scientist, I have seen my work evolve to include aspects of pure and applied science, and I have grown to equally appreciate them both.

I started my current research as a master’s student in an aquatic toxicology lab at the University of Maryland, College Park, under Lance Yonkos. I joined a project to quantify the reproductive impacts of known contaminants—such as dioxins and other persistent organic pollutants—on male mummichogs (Fundulus heteroclitus) from a polluted, urban river on the East Coast. I adapted methods from aquaculture and other disciplines to create what we call a “sperm quality toolkit.” This battery of tests involves visualizing sperm motility, tracking its motion, assessing if it has enough energy for movement, and measuring DNA damage.

The toolkit we developed was specific to our original study site and the reproductive impacts we were looking at there. We then applied it to other areas with similar features, such as the Anacostia River and Hershey Run, a small stream of Delaware’s Christina River. These waters had different chemical contaminants but still had legacy pollution from industry and habitat modification. They also had abundant populations of mummichogs.

By the end of my master’s program, we had found interesting results but were not entirely sure what they meant. At nearly every polluted site we studied, sperm DNA damage was elevated compared to healthy, control fish from the Wye River on the Eastern Shore of Maryland. At sites with higher levels of DNA damage, sperm motility was also the lowest. But for our results to have real-world applications, we needed to support them with pure scientific experimentation.

My original project was funded as a Natural Resource Damage Assessment (NRDA). These legal and scientific assessments aim to understand environmental harm from pollution or other human stressors—and to remedy them by assigning a monetary value the potentially responsible party (PRP) must pay in damages. Until an agreement is met, I cannot publish the exact details of my findings. 

This was a potential drawback when I began my program. It meant I might not be able to publish my work. However, I was so excited! As an undergraduate, I majored in international studies and wanted to specialize in environmental policy to protect our natural resources. I quickly became disillusioned with the idea of making change through top-down policy. I learned I was most passionate about addressing regional issues through research-informed policy and management. Ever since, my goal has been to become an environmental manager, specifically for issues related to water pollution.

Environmental management mainly relies on applied science, so I thought my NRDA projects were the most important work I could be doing. However, as I finished my master’s degree and began my PhD, I saw how important it is to pair applied science with pure science. Although we found evidence that contaminants could be impacting mummichogs, there was little to no foundational research proving they would cause the impacts we saw in wild populations. That foundational evidence is key for environmental managers.

During my Sea Grant research fellowship, we dosed healthy fish in a laboratory setting with the levels of contaminants seen in our study systems. With these pure science experiments, we proved the pollution was the cause of reproductive changes in mummichogs. We are also exploring whether the sperm from impacted fish can fertilize healthy eggs and if it affects the resulting offspring.

Natural Resource Damage Assessments are critical for environmental management. They help us evaluate and restore contaminated ecosystems. However, our tools for these assessments are only as good as the foundational science used to justify them. In a world that increasingly asks, “But what can we do with this research?” and demands applied uses for scientific endeavors, it is important to remember that pure science is how we justify our results. I am a better scientist for having had the chance to participate in both applied and pure science during my fellowship.