https://today.ucsd.edu/story/biodegradable-microplastics Skip to main content Menu * UC San Diego UC San Diego - Today Subscribe Magnifying glass icon * Research * People * Campus & Community * Arts & Culture * Voices Say Hello to Biodegradable Microplastics Research shows plant-based polymers can disappear within seven months Microplastics can take anywhere from 100 to 1,000 years to break down. Much is still unknown about their impacts on the environment and human health. (cr: Whitehoune/iStock) By: * Michelle Franklin - m1franklin@ucsd.edu Media Contact: * Michelle Franklin - m1franklin@ucsd.edu * Mario Aguilera - maguilera@ucsd.edu Published Date March 21, 2024 By: * Michelle Franklin - m1franklin@ucsd.edu Media Contact: * Michelle Franklin - m1franklin@ucsd.edu * Mario Aguilera - maguilera@ucsd.edu Share This: * Twitter * Facebook * LinkedIn * Email Article Content Microplastics are tiny, nearly indestructible fragments shed from everyday plastic products. As we learn more about microplastics, the news keeps getting worse. Already well-documented in our oceans and soil, we're now discovering them in the unlikeliest of places: our arteries, lungs and even placentas. Microplastics can take anywhere from 100 to 1,000 years to break down and, in the meantime, our planet and bodies are becoming more polluted with these materials every day. Finding viable alternatives to traditional petroleum-based plastics and microplastics has never been more important. New research from scientists at the University of California San Diego and materials-science company Algenesis shows that their plant-based polymers biodegrade -- even at the microplastic level -- in under seven months. The paper, whose authors are all UC San Diego professors, alumni or former research scientists, appears in Nature Scientific Reports. "We're just starting to understand the implications of microplastics. We've only scratched the surface of knowing the environmental and health impacts," stated Professor of Chemistry and Biochemistry Michael Burkart, one of the paper's authors and an Algenesis co-founder. "We're trying to find replacements for materials that already exist, and make sure these replacements will biodegrade at the end of their useful life instead of collecting in the environment. That's not easy." "When we first created these algae-based polymers about six years ago, our intention was always that it be completely biodegradable," said another of the paper's authors, Robert Pomeroy, who is also a professor of chemistry and biochemistry and an Algenesis co-founder. "We had plenty of data to suggest that our material was disappearing in the compost, but this is the first time we've measured it at the microparticle level." Putting it to the test To test its biodegradability, the team ground their product into fine microparticles, and used three different measurement tools to confirm that, when placed in a compost, the material was being digested by microbes. The first tool was a respirometer. When the microbes break down compost material, they release carbon dioxide (CO2), which the respirometer measures. These results were compared to the breakdown of cellulose, which is considered the industry standard of 100% biodegradability. The plant-based polymer matched the cellulose at almost one hundred percent. Definitions Biodegradable: Able to be broken down (decomposed) rapidly by the action of living organisms. If something is labeled biodegradable, that doesn't mean it will do so in a reasonable amount of time, or in all environments. Microplastics: Plastic debris measuring between 500 micrometers - 5 millimeters in length. Much is unknown about microplastics and their impacts on the environment and human health. Polymer: Large molecules made of smaller, repeating molecules called monomers. All plastics are polymers, but not all polymers are plastics. Particle counts of petroleum-based (EVA) and plant-based (TPU-FC1) microplastics show that, over time, EVAs exhibit virtually no biodegradation, while the TPUs have mostly disappeared by day 200. Next the team used water flotation. Since plastics are not water soluble and they float, they can easily be scooped off the surface of water. At intervals of 90 and 200 days, almost 100% of the petroleum-based microplastics were recovered, meaning none of it had biodegraded. On the other hand, after 90 days, only 32% of the algae-based microplastics were recovered, showing that more than two thirds of it had biodegraded. After 200 days, only 3% was recovered indicating that 97% of it had disappeared. The last measurement involved chemical analysis via gas chromatography/mass spectrometry (GCMS), which detected the presence of the monomers used to make the plastic, indicating that the polymer was being broken to its starting plant materials. Scanning-electron microscopy further showed how microorganisms colonize the biodegradable microplastics during composting. "This material is the first plastic demonstrated to not create microplastics as we use it," said Stephen Mayfield, a paper coauthor, School of Biological Sciences professor and co-founder of Algenesis. "This is more than just a sustainable solution for the end-of-product life cycle and our crowded landfills. This is actually plastic that is not going to make us sick." Creating an eco-friendly alternative to petroleum-based plastics is only one part of the long road to viability. The ongoing challenge is to be able to use the new material on pre-existing manufacturing equipment that was originally built for traditional plastic, and here Algenesis is making progress. They have partnered with several companies to make products that use the plant-based polymers developed at UC San Diego, including Trelleborg for use in coated fabrics and RhinoShield for use in the production of cell phone cases. "When we started this work, we were told it was impossible," stated Burkart. "Now we see a different reality. There's a lot of work to be done, but we want to give people hope. It is possible." Full list of authors: Robert S. Pomeroy, Michael D. Burkart, Steven P. Mayfield (all UC San Diego), Marco N. Allemann, Marissa Tessman, Jaysen Reindel, Gordon B. Scofield, Payton Evans, Ryan Simkovsky (all Algenesis). This research was supported by funding from the Department of Energy (DE-SC0019986 and DE-EE0009295). Disclosure: Burkart, Mayfield and Pomeroy are co-founders of and hold equity positions in Algenesis Corporation. Share This: * Twitter * Facebook * LinkedIn * Email You May Also Like San Diego Supercomputer Center Interns Create App for UC San Diego's Stuart Collection The Arts Say Hello to Biodegradable Microplastics Science & Environment Focus on South Asia Giving UC San Diego Professor Awarded Signal Processing Society's Highest Honor Technology & Engineering Say Hello to Biodegradable Microplastics Science & Environment Focus on South Asia Giving UC San Diego Professor Awarded Signal Processing Society's Highest Honor Technology & Engineering San Diego Supercomputer Center Interns Create App for UC San Diego's Stuart Collection The Arts Stay in the Know Keep up with all the latest from UC San Diego. Subscribe to the newsletter today. Email [ ] Please provide a valid email address. Subscribe Subscription Notification Close Confirmation Thank you! You have been successfully subscribed to the UC San Diego Today Newsletter. Contact Information UC San Diego Homepage 9500 Gilman Drive, La Jolla, CA 92093-0021 (858) 534-2230 Site Directory * Media Resources & Contacts * Newsletter * Emergency Status * Disability Resources * Principles of Community * Equity, Diversity and Inclusion * University Communications Follow Us on Social Media * Facebook * Twitter * Youtube * Instagram * LinkedIn * Tiktok Divisions & Schools * Arts and Humanities * Biological Sciences * Division of Extended Studies * Division of Graduate Education and Postdoctoral Affairs * Division of Undergraduate Education * Halicioglu Data Science Institute * Jacobs School of Engineering * Physical Sciences * Rady School of Management * School of Global Policy & Strategy * School of Medicine * Scripps Institution of Oceanography * Skaggs School of Pharmacy * Social Sciences * Wertheim School of Public Health (c) 2021 Regents of the University of California. All rights reserved. Terms of Use | Accessibility | Privacy | Feedback Category navigation with Social links X icon Close * Research Right pointing chevron Research Right pointing chevron Right pointing chevron Back + The Arts + Business & Economics + Health & Behavior + Humanities + Politics & Society + Science & Environment + Technology & Engineering All Research Collapse Research navigation * People Right pointing chevron People Right pointing chevron Right pointing chevron Back + Awards & Accolades + In Memoriam + Milestones + Profiles All People Collapse People navigation * Campus & Community Right pointing chevron Campus & Community Right pointing chevron Right pointing chevron Back + At Work + Athletics + Campus News + Giving + Student Life All Campus & Community Collapse Campus & Community navigation * Arts & Culture Right pointing chevron Arts & Culture Right pointing chevron Right pointing chevron Back + Books & Culture + Events & Happenings + Visual & Performing Arts All Arts & Culture Collapse Arts & Culture navigation * Voices Right pointing chevron Voices Right pointing chevron Right pointing chevron Back + Insights & Experts + Opinion + Q&A All Voices Collapse Voices navigation * Visual Storytelling Visual Storytelling For Media: * Media Resources & Contacts Right pointing chevron Newsletter Right pointing chevron Signup to get the latest UC San Diego newsletters delivered to your inbox. Magazine Right pointing chevron Award-winning publication highlighting the distinction, prestige and global impact of UC San Diego. Follow Us: * Facebook * Twitter * Youtube * Instagram * LinkedIn * Tiktok UC San Diego Homepage X icon Close Close X icon Search UC San Diego Today [ ] Search Search