Relating microplastic counts in sediment cores to macroeconomic variations within the last century
Many negative socioeconomic and ecological implications are associated with plastic pollution. In Canada, microplastics (MPs; particles <5 mm) have been classified as an emerging environmental contaminant that is threatening the health of the Laurentian Great Lakes system (LGR).
These lakes, containing 21% of the world’s fresh water, have been shown to contain abundant MPs in their bottom sediment. Investigations focusing on microplastic pollution in lake sediment cores, however, are lacking for the Great Lakes, and are rare globally.
Read this open access paper on the FACETS website.
Our goal was to study the abundances, types, and vertical distribution of 0.053mm — 2 mm sized MPs in two sediment cores from Lake Huron and Lake Ontario, Canada.
We found that the core slices contain 18.1–488.4 particles per gram of dry weight sediment, and that these small plastic particles have been accumulating for 56 and 72 years in lakes Huron and Ontario, respectively.
By matching microplastic abundance profiles with years, as determined from sediment accumulation rates, we note that MPs are least abundant immediately following global and national economic crises.
These economic downturns are associated with decreased plastic production and consumption and thus, a lower number of MPs enter the environment.
Our study shows that microplastic abundances in sediment cores can be representatives of macroeconomic shifts, as well as regional influences.
Read the paper — A temporal record of microplastic accumulation in sediment cores of the Great Lakes, North America, reflects macroeconomic and regional influences by Sara L. Belontz, Patricia L. Corcoran, Linda Kimpe, Paul A. Helm, and Chris Marvin.
