Presence of Microplastics in Nebraska

Small plastic particles smaller than five millimeters are commonly referred to as microplastics and represent a pollutant of increasing concern. The majority of research performed to date has been conducted in the marine environment; however, in recent years there has been an increased effort to study microplastics within the freshwater environment. Results published thus far indicate microplastics have a ubiquitous presence in the environment. Currently, there is no information on microplastic abundances within the state of Nebraska. The goal of this research was to perform a preliminary investigation into the existence of microplastics in water bodies within the state and the potential microplastic contributions of wastewater treatment plants (WWTP). In pursuit of this goal, two types of samples were collected: environmental samples from five water bodies and contamination vector samples from two WWTP. Environmental samples consisted of shoreline sediments collected by citizen scientists and were processed using an elutriation column and published methods. Contamination vector samples from the two WWTP consisted of effluent samples and finished biosolids samples. Effluent samples were processed according to published methods while the biosolids were processed using a method developed during this research project that allowed approximately four times greater sample volumes to be used than previously published methods. Results indicate microplastics exist in Nebraska in abundances similar to those published in literature. The environmental samples fell within the bounds of previously reported results although high sample variance made it difficult to draw any definitive conclusions. Samples collected from the WWTP indicate they are a significant contributor of microplastics into the environment. Microplastic abundances were much higher in the contamination vector samples than those of the environmental samples. In addition, microplastic abundances in both WWTP effluent and biosolids samples found in this study were significantly higher than those reported in literature values. Additional research is proposed to better quantify microplastic abundance and increase understanding of the fate and transport of these particles within Nebraska’s environment. Adviser: Shannon Bartelt-Hunt