Management of Environmental Plastic Pollution: a Comparison of Existing Strategies and Emerging Solutions from Nature

Abstract The recalcitrance of modern plastics is a key driver of the accretion of plastics in both waste management streams and the environment. As a result, the management of plastic waste has become a focal point of both research and public policy. The following review summarises the effectiveness of widespread approaches to plastic management, before exploring recent developments in the use of both naturally derived products and plastic-degrading organisms to reduce the burden of plastic wastes, including the potential value of symbiotic relationships between plastic-degrading organisms in the biodegradation of plastics in the environment. To date, plastic management strategies have typically focused on interventions to influence both plastic production and consumer behaviour, improvements in effective waste management systems and increased circularity of materials, and changes to the product design to increase the lifespan of the product and its suitability for preferred waste streams. However, the relative success of these measures has been mixed. Complementary to these established approaches is the increasing exploitation of biological and biochemical processes and natural products, including the identification of organisms and enzymes which are able to biodegrade different plastics at meaningful rates. This recent research frequently focuses on microbes from soil and marine environments, identifying numerous enzymes capable of acting on polymers or specific functional groups. While questions remain as to their effectiveness outside of laboratory conditions, the distribution of identified species and their apparent effectiveness indicates the potential benefits of these microbes both individually or in symbiosis with an appropriate host species. Graphical Abstract Overview of plastic life cycle and current management strategies. Arrows indicate the flow of plastic material; thicker-lined boxes highlight plastic management beyond simple landfilling. Pros and cons for different stages and management are listed above and below items, respectively. WWTP: Wastewater treatment plants.