Life Cycle Assessment of PLA Products: A Systematic Literature Review

The rising concerns about environmental harm and pollution create a setting for the search for better materials to produce more sustainable products. Plastic plays a crucial role in modern life and most of the commonly used are of fossil origin. Polylactic Acid (PLA) has been appointed as a more sustainable alternative, due to its origins in biodegradable raw materials. This paper aims to review scientific research, where Life Cycle Assessment (LCA) is performed on this material, in order to further understand the environmental impacts and to assess whether it is a more viable option when compared to the most commonly used plastics. A systematic literature review of 81 LCA studies focused on the LCA of PLA products was conducted. An assessment of key aspects, including the system boundaries, raw materials origin, and quantitative analysis of five environmental impact categories was performed. In this comparative analysis, in addition to presenting the results for PLA products, they are also compared with other fossil-based plastics. This leads to the conclusion that PLA has higher environmental impacts on Marine Eutrophication, Freshwater Eutrophication, and Human Toxicity, which are mainly related to the agricultural phase of growing the raw materials for PLA production. For Climate Change, Polystyrene (PS) presents the higher Greenhouse Gas (GHG) emissions, and for the Ozone Layer Depletion category, Polyethylene terephthalate (PET) presents the higher impact. PLA is a solution to replace fossil plastics. However, the use of alternative biomass sources without competition with the feed and food sector could be a key option for biobased materials production, with lower environmental and socioeconomic impacts. This will be a pathway to reduce environmental impacts in categories such as climate change, marine eutrophication, and freshwater eutrophication.