104b Base Grants – A contaminant of Emerging Concern in Indiana Rivers

Water quality degradation resulting from human activities represents a threat to environmental and human health. Contaminants of emerging concern, including microplastics (plastic particles <5 mm in size), are understudied in flowing waters of the Midwestern USA including in Indiana. Microplastics can enter rivers and streams through a variety of pathways (e.g., wastewater effluent, breakdown of larger plastic debris, atmospheric deposition) and can negatively impact aquatic organisms through both direct consumption with food and indirect contamination from sorbed toxins. Here we propose to quantify the concentration and types (e.g., microbeads, fibers, fragments) of microplastics found in Indiana watersheds representing a gradient of land use (i.e., agricultural, urban, or forested). While we expect to find microplastics at all sites, we hypothesize that watersheds dominated by modified land use types (i.e., agricultural and urban) will have higher concentrations of microplastics as a result of increased human influence. Based on our previous work quantifying microplastics in the St. Joseph River watershed of Indiana, we have developed sampling techniques that allow us to determine both the abundance and the type of microplastics. Identifying the sources and types of microplastics in Indiana waters will provide valuable information for our state and is critical for the development of management actions for this emerging contaminant.