Biodegradation of microplastics in food and agriculture

Microplastic particles and fibers are widely distributed pollutant in the food and agriculture systems. While a growing number of studies have shown that microplastics are toxic to plant and animal life, systemic efforts to reduce their presence have been scarce. Research on how microplastics spread points to wastewater treatment plants as a key source from which microplastics may enter natural bodies of water, groundwater, or terrestrial ecosystems. In parallel, discovery of microorganisms capable of plastic degradation through enzymatic depolymerization has created growing interest in use of biocatalysis to reduce the number of microplastics released into the environment. In this review, we summarize the current state of the microplastic literature, focusing on their presence in wastewater treatment facilities and their biodegradation by microorganisms. We propose introduction of microplastic degradation by engineered enzymes in situ in currently employed wastewater treatment unit operations. To conclude, we highlight other areas of the food and agricultural systems that may benefit from biocatalytic interventions for microplastic biodegradation.