THE MIGRATION OF MICROPLASTICS BETWEEN FRESHWATER AND SALTWATER SYSTEMS: A COASTAL NORTH CAROLINA INVESTIGATION FROM THE NEUSE RIVER TO THE ATLANTIC OCEAN

Microplastics, pieces of synthetic plastic smaller than 5.0 mm in diameter, are present in many waterways and generate both known and unknown impacts on the environment and human health. Even though the microplastics presence in our waterways is of increasing concern, how microplastics travel between freshwater and saltwater environments is not yet understood. This pilot study examines freshwater, saltwater, and brackish surface water grab samples from ten locations near the Neuse River in Coastal North Carolina collected in July 2023. The Neuse River was named American Rivers’ 2022 River of the Year due to its importance including providing drinking water for approximately one quarter of North Carolina’s population (American Rivers, 2022). Although microplastics contamination of the Neuse River has been studied (e.g., Kurki-Fox et al., 2023), the migration from the Neuse to other waterways is less researched. Sample sites include the Neuse River, along Adams Creek and Harlow Creek, and into the Atlantic Ocean. Analysis methods include wet sieving, wet peroxide oxidation, density separation, and microscopic examination to determine the presence and concentration of microplastics in each sample. The types of microplastics and their concentration will be discussed in the context of microplastic movement between freshwater and saltwater ecosystems.