A new modelling study in Barcelona compares the environmental and health impacts of bottled, tap, and filtered drinking water. The research finds that while tap water has the lowest carbon footprint, bottled water remains the most common choice despite having the highest greenhouse gas emissions. Domestic filtration systems, particularly reverse osmosis, are highlighted as a potential middle ground. These systems can reduce exposure to harmful chemicals like nitrates and trihalomethanes without the massive carbon overhead associated with plastic bottle production and transport.
