Victoria Fulfer

I am very excited to announce that our study on the sedimentary storage of plastics in Narragansett Bay, RI has been published in Scientific Reports.

This study involved some fun field work, methods development to find the most efficient and effective way to separate microplastics from sediment samples, and a huge amount of data analysis. I could not be more proud of the end result.

Abstract

Plastics are an important new component of the global sedimentary system, and much concern exists about their transport, fate and impact. This study presents the first system-scale assessment of sedimentary storage of microplastic for an estuary, Narragansett Bay, RI (USA), and the measurements of shoreline and seabed sediments add to the growing body of literature demonstrating high coastal concentrations. Microplastic concentrations in sediments ranged from 396 to over 13,000 MP particles kg⁻¹ dry sediment (DW), comparable to other shoreline and seafloor sites located near urban centers. As previously reported for fine sediment and other pollutants, estuarine plastic storage is extensive in Narragansett Bay, especially within the upper urbanized reaches. Over 16 trillion pieces of plastic weighing near 1000 tonnes is calculated to be stored in surface sediments of the Bay based on a power-law fit. This work highlights that estuaries may serve as a significant filter for plastic pollution, and this trapping may have negative consequences for these valuable, productive ecosystems but offer potential for efficient removal.

Read the full article here:

https://www.nature.com/articles/s41598-023-36228-8#Abs1

A negative power-law relationship between microplastic concentration (particles kg⁻¹ dry sediment) in subaqueous sediment and the distance from Providence, RI (km) exists (R² = 0.85; a). Error bars represent one standard deviation from the mean. Some error bars are sufficiently small to be contained within the circle symbol. Using this relationship, the depth of the sediment sampled (top 5 cm), the average density of the sediment (1.7 g cm⁻³) and the average mass per plastic particle (5.86 × 10⁻⁵ g particle⁻¹), the predicted amount of plastic contained in any given area of the Bay is calculated. This is mapped onto a grid of Narragansett Bay (b). When the total area of the bay is summed, the mass of microplastics contained in the top 5 cm of subaqueous sediment totals 9.76 × 10⁵ kg, or 976 tonnes. Over 50% of microplastics are estimated to be stored in the upper Bay proximal to the city (c). Satellite image derived from Google Earth v7.3.6.9345 (December 14, 2015; https://earth.google.com/) and edited using a grid from Global Multi-Resolution Topography Synthesis (GMRT)

Fulfer, V.M., Walsh, J.P. Extensive estuarine sedimentary storage of plastics from city to sea: Narragansett Bay, Rhode Island, USA. Sci Rep 13, 10195 (2023). https://doi.org/10.1038/s41598-023-36228-8