Metals can also affect water quality. Freshwater eutrophication shows that the production and processing of materials may create effects beyond energy use or CO2 emissions. Water, soil, health and climate are connected in material decisions.
In the Binas contribution, material impact is therefore broader than a single score. The value lies in comparison: metals can perform differently on climate, acidification, eutrophication, health, scarcity and recycling. For education and design practice, that helps prevent oversimplified choices and supports a more systematic view of material impact.