BRC-BIO: Undergraduate Researchers Investigating the Biological Effects of Environmental Microplastics

Humans are influencing the environments in which animals live in many respects. As we are facing a major biodiversity crisis, understanding the effects of human induced environmental change is increasingly important. One such change which is particularly widespread is the presence of microplastics in nearly all environments.

That these particles are being incorporated into animal tissues is now widely documented but their effects on animal physiology and development are much less studied. This study focuses on characterizing how exposure to concentrations of microplastics that are occurring in the natural environment affect physiological and neurological development in an amphibian model.

The results of this research will contribute to the call from the UN Environmental Program for more research on these effects. This work will also contribute to a more diverse and competitive scientific workforce in the country by expanding opportunities for undergraduate students to conduct authentic research through individualized research projects and course-based undergraduate research experiences.

Research students will participate in service-learning at local minority school districts to become role models and increase scientific interest in our country’s middle school students.

Microplastic exposure has been most studied in marine invertebrates and fish with little work done on freshwater and terrestrial organisms. Previous research has found that microplastics cause damage to the gills, digestive tract, liver, and to some cellular structures. Yet, many of these studies used unrealistically high concentrations of microplastics for most environments (microplastics exist in nature at a range of concentrations, with the highest concentrations found in marine areas where microplastics accumulate due to oceanic currents).

Further, most of the research on microplastics relies on acute exposures (generally limited to one day, up to a week), making the impact of chronic exposures unclear. The research proposed in this study will fill these knowledge gaps by having undergraduate students conduct mentored research projects to investigate the effects of exposure to environmentally realistic concentrations of microplastics in aquatic ecosystems.

Project aims include determining the fate of microplastics once they enter the body, assessing developmental changes to the digestive tract, and analyzing effects of microplastics on neurodevelopment (behavior and brain structure). A series of controlled laboratory and mesocosm (artificial pond) experiments will be used to chronically (weeks to months) expose larval amphibians to water contaminated with microplastics at a low concentration (