Environmental performance of bioplastic packaging on fresh food produce: A consequential life cycle assessment

Abstract

Polylactic acid (PLA) is a compostable bio-based plastic that can be used for food packaging, potentially increasing separation of (packaged) food waste for targeted, more circular organic waste management via anaerobic digestion, industrial composting, or (in the future) insect protein meal feed production. Consequential life cycle assessment (LCA) was undertaken to rigorously assess the environmental impact of displacing petrochemical plastic packaging of fresh fruit and vegetables with PLA. Eight end-of-life scenarios of bioplastic packaging were evaluated against a business-as-usual petrochemical packaging scenario, expanding LCA boundaries to include end-of-life impacts of fruit and vegetable food waste within a UK context. PLA production has a higher impact compared with petrochemical plastic production across many impact categories, but diversion of PLA-packaged food waste to organic recycling can compensate for this, improving the overall environmental performance of bioplastic packaging scenarios. Future diversion of organic waste streams to insect feed (following regulatory change) would lead to the best environmental outcomes, followed by anaerobic digestion. Impact categories ameliorated in bioplastic scenarios include human health effects, climate change, freshwater eutrophication, ionising radiation, photochemical ozone formation, resource use energy carriers, and respiratory inorganics. On the other hand, petrochemical plastic scenarios generate smaller burdens for acidification, marine and terrestrial eutrophication, ozone depletion, and water scarcity. Sensitivity analyses indicate high improvement potential for bioplastic scenarios if the energy efficiency of PLA production can be increased, or if globalised production shifts to industrialised countries with cleaner energy mixes (that currently import most of their plastics). Whilst end-of-life management of the fruit and vegetable food waste has a considerable influence on environmental outcomes, plastic packaging represents a surprisingly large share of the dry matter material flow (about 25%) in fresh produce waste streams. Therefore, it is imperative that future LCA studies of food packaging account for both packaging and (diverted) food waste end-of-life flows.