Local engineers are part of multidisciplinary teams studying microplastic pollution by Steven Day, Christy Tyler, Samantha Romanick, James Roussie, James McGrath Over the last decade there has been a lot of attention given to plastic waste that enters the environment. The waste generated from these durable, lightweight plastics behaves differently than materials of the past. It doesn’t degrade quickly and many polymers have a density that is less than or near enough to water that plastic can move through our water in ways that we’re only recently coming to understand. Plastic bags and six-pack rings affecting marine mammals captured attention decades ago and images of giant garbage patches in the oceans were circulated widely several years ago. More recently, our ideas about the many different ways that plastics can end up in our environment and affect the health of the ecosystem and humans has evolved from the concept that large quantities of waste ends up floating in the ocean. The first change is our increased awareness of microplastics, some of which are manufactured at a small scale, and others of which are formed by the breakup of macro materials due to weathering, wear, and mechanical forces. These microparticles, classified as anything smaller than 5 mm, may not even be visible to the eye. Secondly, there is recent attention on freshwater systems, including rivers and lakes. Plastics behave differently in freshwater systems, in part because the density of the water itself is lower than ocean water, making it more likely that plastics will sink, rather than float. Third, there is a recent awareness that microplastics are small enough to travel suspended in water, or even air, and are ingested or inhaled by humans. Local engineers and scientists are working to better understand how microplastics move through freshwater systems and affect ecosystems and human health. The participants in many separate projects collaborate through a microplastics workgroup, which includes close to thirty participants from seven different organizations. This workgroup comes together once a month to share recent findings in the literature as well as their own research on the topics of microplastics in our environment, human exposure to microplastics, and MP effects on wildlife and human health. Organizations represented in this group include Rochester Institute of Technology, University of Rochester, UR Medical Center, SiMPore Inc., Parverio Inc., Ithaca College, and Ithaca Area Wastewater Treatment Facility/Cornell University. Participants include high school students, undergraduate and graduate students, postdoctoral associates, professors, managers, and directors. The 10 | The ROCHESTER ENGINEER JUNE 2021
workgroup includes investigators conducting studies on: 1) the transport and ecological impact of MPs on the Greater Rochester Area’s many waterways; 2) the health impacts of MPs including the potentially toxic chemicals they can leach or adsorb; 3) the development of affordable and rapid methods to extract and identify microplastics in liquids and room air, and 4) the amount of microplastics people in Rochester are ingesting through drinking water or inhaling through room air. A few of these projects are described here.
What are the effects of these plastics on freshwater ecosystems, such as Lake Ontario? The Laurentian Great Lakes span nearly 95,000 square miles and are the largest connected freshwater system in the world. They supply water for consumption, power, and recreation to the 30 million people that live in the Great Lakes basin. Matt Hoffman and others at RIT have estimated that only a small fraction (4 tons) of the approximately 2,500 tons of plastic that enter Lake Erie annually are floating on the surface and have shown similar data for Lake Ontario. An interdisciplinary team at RIT, led by Christy Tyler (an ecologist), and Hoffman (a mathematician), with Steven Day (mechanical engineer), Nathan Eddingsaas (a chemist), and Andre’ Hudson (a molecular biologist) is trying to understand the fate and impact of the “missing plastic”. In addition to the mechanical and solar breakup of larger plastics into microplastics, there is a relationship to the biological environment. An ongoing project funded by the National Oceanic and Atmospheric Administration’s New York Sea Grant College Program is investigating the toxicity of the plastics on aquatic organisms as well as the biological effects on the particles.
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