Environmental performance of different water bottles with different compositions: A cradle to gate approach

Abstract

Plastic production has increased over the years and the packaging industry was responsible for 44% of the total plastic production. Polyethylene terephthalate (PET), due to its favorable properties, is one of the most used polymers in this sector.

This study first aimed to compare the environmental performance related to the production of a novel recycled PET (rPET) form, namely, rPET flake, and then compare it with the production of virgin PET (vPET) and rPET pellet. Secondly, this study aimed to compare the environmental impacts of four water bottles with different compositions, namely, option A composed with only vPET, option B made with 50% vPET and 50% rPET pellet, option C made with 75% rPET pellet and 25% rPET flake, and option D made with 50% vPET, 25% rPET pellet and 25% rPET flake. Option A was designed as a single-use water bottle, while the remaining options (Options B, C and D) were thought to be reusable bottles, and for that reason were heavier and more robust compared to Option A. The environmental impact assessment followed the International Standard Rules of Life Cycle Assessment (LCA), and the impact assessment method used was the Environmental Product Declaration. Ecoibéria and Logoplaste provided the majority of the required data, and three functional units were considered. The first one was the production of 1 kg of PET, the second was the production of different water bottles, and finally, the third one was the consumption of 2 l of water with different water bottles. As a result, it was first observed that the production of rPET flake in comparison to vPET reduces, on average, 79% of the impacts, and rPET pellet reduces 10% of the impacts. Secondly, in the production of the different water bottles, Option A, the single-use bottle, presented the lowest environmental impacts in almost all categories. Finally, when taking into account the reusable factor, the use of single-use bottles presented the higher environmental impact in all categories, probably because of the dilution of the environmental impacts associated with the production of heavier and robust reusable bottles by the multiple times of uses of these bottles.