Timnit Kefela

PhD Graduate

Year Admitted
2016

Year Graduated
2023

Research Areas
plastic pollution, microplastic pollution, environmental microbiology

Faculty Advisor
Patricia Holden

Committee
Arturo Keller, Joshua Schimel

Dissertation Title & Abstract

(Micro)plastics in Solid Environmental Matrices

Plastics are materials that have become a crucial component of our daily lives. Their versatility and durability, however, contribute to their prevalence and persistence in the environment, posing toxicological risks to biota. Therefore, understanding plastic sources, pathways, and fates within the environment is instrumental in identifying infrastructural solutions that can limit their negative impact. Single-use packaging, specifically multilayer packaging, is a well-identified source of plastic waste. Yet, present waste management strategies primarily focus on landfills as their fate because of their incompatibility with predominant recycling technologies. This dissertation research, through mesocosm studies, explored plastic biodegradation as a waste management strategy by bioprospecting for hydrocarbonoclastic and cellulolytic bacterial consortia colonizing the surfaces of plastics which comprise the different layers of multilayer packaging. Evidence of plastic biodegradation was further evaluated via analyses of physicochemical indicators. Finally, a method was developed for microplastic extraction from field soils to assess their pathways and fates in solid matrices.

Education
BS, Biology, Rutgers University - Camden
MS Biology, Rutgers University - Camden