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There have been numerous discussions about plastic drinking straws and their impacts on the natural environment, reflecting on public policies and companies’ operation, while alternatives to substituting plastic-based products have been proposed. However, making decisions without measuring trade-off conditions between the different scenarios may lead to higher impacts elsewhere on the life cycle or even in other areas of protection. To deepen this discussion, this paper aimed to quantify the potential environmental impacts of different drinking straws as well as find possible break-even situations. A comparative life cycle assessment (LCA) was performed to assess six different drinking straws (plastic, stainless steel, glass, paper, bamboo and jute) from cradle-to-grave. A hybrid life cycle impact assessment (LCIA) method was applied following the characterization models recommended by ILCD. Sensitivity analyses included reuse rate, washing condition, the ancillary kits usage, End-of-Life (EoL) strategies and the inclusion of an indicator to account for the marine litter impacts from Life Cycle Inventory (LCI). Results showed that for baseline scenarios, plastic drinking straws have a better environmental performance if compared to reusable straws and has a favourable performance in 10 of 11 categories if compared to paper drinking straws. Water and detergent consumptions during the use phase and the manufacturing of additional elements (bag, brush) are the main drivers for this potentially higher environmental impact. Sensitivity analyses, however, showed that certain consumption patterns may lead to a break-even situation, especially when plastic drinking straws are disposed incorrectly into the natural ecosystem. Accounting for the impacts of marine litter may lead to a change in the decision-making depending on the significance (weight) attributed to the marine litter indicator. These outcomes reinforce the importance of understanding trade-offs during the entire life cycle of products and demonstrate that policies directed to product substitution should be carefully grounded. Recommendations on reusable straws rely on simplifying their “kits”, expanding reuse rates and improving the washing process. For single use straws, waste collection and correct disposal are mandatory. The lack of a LCIA methodology to account for the environmental impact of mismanaged plastic waste on ecosystems, especially in the marine compartment represents an important issue to be further developed, from which, more realistic scenarios could be outlined for any product.

The road construction is one of the main responsible for resource use and has been targeted as criterion development in updated versions of the Green Procurement Policy (GPP) in Europe. Although major progress was achieved in road pavements and lightning systems during the past decade, discussions on the environmental sustainability of additional road elements can advance the current understanding on how to decrease the impacts on highways. The aim of this study was to compare the potential environmental impacts of two anti-glare safety devices used on highways: the plastic (polymer-based) and the steel screen (steel-based). To this end, we applied the life cycle assessment (LCA) methodology following ISO standards based on a cradle-to-grave approach. The impacts of both anti-glare devices are driven by the main raw materials. This condition means that the weight of products is a key issue when evaluating the sustainability of the anti-glare devices. The plastic anti-glare (PAG) consumes significantly less materials and thereby presents the most favourable environmental performance for all the impact categories. For the products' manufacturing analysis, the hot-dip galvanizing was the process with higher impacts for both devices, as the setup kit of the PAG is also made from galvanized steel. Adopting sustainable strategies, e.g. product's recycling at end-of-life, use of recycled materials and product's setup with Li-ion battery, may provide an average impact reduction of 19% and 6% for the PAG and the steel screen anti-glare (SAG), respectively. A break-even situation for all the environmental impact categories occurs when the steel screen weight is reduced from 8.0 kg to less than 1.80 kg. Major attention has been addressed to road pavements and lighting system when evaluating the life-cycle impacts of highways, but our results highlight that the impacts of road sector can be offset by focusing in additional elements, such as the anti-glare device.