Microbial Photo-Biodegradation of Plastics and Bioplastics

Project Number
Project Date Range
Funding Agency
National Oceanic and Atmospheric Administration (NOAA)
Focus Area(s)
Resilient Coastal Communities and Economies




This study focuses on the impact of  photodegraded petro- and bio-based plastics on coastal settings. By analyzing which compounds, such as additives, leach from plastics into surrounding seawater, this study will compare the environmental effects of these materials by illustrating their influence on microbial community structure and additive toxicity. 



While plastic has revolutionized all industrial sectors, we now know it does not sustainably degrade. Instead, it breaks down into microplastic particles and fibers measuring less than 5mm. These particles often evade waste collection and can pose serious hazards like globally transporting pathogenic bacteria and disrupting biological systems through bioaccumulation in animals. This project will further our understanding of plastic environmental impacts by comparing how the ultraviolet (UV) radiation and microbial degradation of petro- and bio-based plastics affect coastal waters. 

Researchers will use laboratory experiments to observe how plastic leachate affects microbial communities from seawater with high and low inputs of oil. Analysis of microbial community diversity and density based on the photo leachate of the material will identify the environmental effects of petro- and bio-based plastics and potential natural processes for sustainable plastic degradation.

Microplastics and impending climate challenges are multi-generational threats. Findings from this research will be widely disseminated to professionals and students, including underrepresented communities around Santa Barbara with high representations of Latinx and indigenous students through “Next in STEM,” a new long-term outreach program through UCSB’s “Womxn in Science and Engineering” (WISE). Researchers will create a dynamic outreach program that brings graduate student and postdoc speakers to these high schools and hold community building events where challenges of microplastics can be discussed onsite. 

This research can also apply at the policy level with engagement with the advisory board of Senate Bill-54 which aims to investigate desired recyclable and compostable standards for California’s plastics market with a focus on end-of-life processes for these materials.

Community Mentors: Scott Coffin (State Water Resources Control Board), Win Cowger (Moore Institute for Plastic Pollution Research)


Principal Investigators
David Valentine
University of California, Santa Barbara (UCSB)
Co-principal Investigators
Sara Matsumura
University of California, Santa Barbara (UCSB)