Plastic debris in the marine environment has been a growing concern due to its durability in the ocean environment and the potential to have a variety of impacts on marine organisms. Characterization of plastic debris is approached via size as macroplastics (> 5mm), microplastics (5-0.330mm), and nanoplastics (<0.330mm), all of which are located in surface waters, within the water column, on beaches and within seafloor sediments. This is a preliminary study on monitoring plastics debris in marine sediments in Puget Sound with the goal of establish a baseline to determine the concentrations of plastics in marine benthic communities and work to deepen our understanding of the impacts of plastic debris on marine ecosystems throughout the Pacific Northwest. In collaboration with the Washington State Department of Ecology’s, Marine Sediment Monitoring Team (MSMT) and the Puget Sound Ecosystem Monitoring Program (PSEMP), ten samples weighing 200 grams each were processed and analyzed from different stations around Puget Sound. Plastic fibers of various colors and sizes were found throughout the samples as well as white plastic shards; foam and film. After multiple density separations it was determined that Bellingham had the highest concentration of microplastics at 2.48E-03 milligram (mg) of microplastics per gram (g) of sediment. The lowest concentration was found at Sinclair Inlet with 4E-05 (mg/g) of microplastics. Further analysis was performed to determine whether there was a correlation between concentration of microplastics and particle size of sand, silt and clay at each of the ten stations sampled. When comparing percent of sand, silt and clay it was determined that there was no correlation with an R value of 0.04 for sand, 0.01 for silt and 0.1 for clay. Future studies include identifying each plastic fiber using infrared spectroscopy and processing/analyzing samples gathered from past years.

Alexandrium is a genus of dinoflagellate that produces saxitoxin, which is known to cause paralytic shellfish poisoning when shellfish contaminated with high concentrations of Alexandrium are consumed. Due to the possibility of toxicity and negative economic impacts, the presence of Alexandrium is regularly monitored throughout the Puget Sound. Alexandrium spends part of its life cycle as a cyst in the sediment before germinating to become a free-swimming dinoflagellate. Alexandrium cysts in surface sediments are used to determine the present spatial distribution of this organism. Cyst concentrations in sediment cores can be used to evaluate historical presence and temporal variability. A research project from 2005, funded by NOAA’s ECOHAB program, has shown that surface sediments in Quartermaster Harbor (QMH), a harbor with low flushing rates due to its geographical orientation, have the highest abundance of Alexandrium cysts in Puget Sound. In July 2010, sediment cores were collected from five locations in Puget Sound to determine the historical distribution of Alexandrium. The purpose of this study is to quantify Alexandrium cyst concentrations in a 202 cm Kasten core collected from the inner harbor of QMH. Sediments were prepared for by sieving material between 20 and 90 µm and staining with Primulin before being analyzed for Alexandrium presence under epifluorescence using an FITS filter on a compound microscope. Preliminary results show maximum cysts/mL sediment near the surface, regressing to 0 cysts/mL sediment below 30 cm. The core was characterized by analyzing the grain-size distribution and organic content of each sub-sample of the core in order to determine if there is a relationship between cyst abundance and these properties. 210Pb dating was completed in order to correlate cyst abundance and local changes to the harbor.