Overview

• Mid-2025 NO₂ concentrations in Barcelona averaged 22.5 µg/m³ citywide, marking the lowest levels recorded since 2000.
• The city now complies with existing EU limits but remains above the tighter 2030 EU threshold of 20 µg/m³ and the WHO guideline of 10 µg/m³.
• Barcelona’s low-emission zone, expanded green spaces and sustainable mobility initiatives are credited with driving a 2 %–14 % drop in NO₂ across seven monitoring sites in the first half of 2025.
• Particulate matter (PM10 and PM2.5) levels have been stagnant since 2013 and continue to exceed the legal ceilings set for 2030.
• The decline in air pollution has translated into a 32 % reduction in related health risks compared with 2018–2019 levels, though authorities warn further action is needed.