Life Cycle Assessment of Plastic Water Bottles: Comparing Environmental Impact of PET and PC, with a Focus on Different End-of-Life Treatment Methods

This study evaluates the environmental impact of PET and PC water bottles from a life cycle perspective, including the production, use, and end-of-life (EoL) phases. The environmental impacts were analyzed across 11 impact categories at the midpoint level based on the CML-Baseline methodology. For the EoL phases, incineration, landfilling, and recycling (PET only) were considered. Under the considered scenarios, PET bottles had lower environmental impacts than PC bottles in categories such as fossil fuel depletion, acidification, global warming, photochemical oxidation, and terrestrial ecotoxicity. In contrast, PC bottles had lower impacts on abiotic resource depletion, eutrophication, freshwater ecotoxicity, human toxicity, marine ecotoxicity, and ozone layer depletion. These findings reflect differences in the production and disposal processes of the two materials. At the same time, recycling effectively reduces most environmental impacts, such as PET bottles. Additionally, environmental impact contributions from each unit process with sensitivity analysis were conducted for categories such as global warming and photochemical oxidation to assess the impact from transportation distances, highlighting the significance of transportation. This study emphasizes the importance of policies aimed at reducing environmental impacts and the role of recycling in waste reduction and resource conservation, supporting the transition to a circular economy.