Murcia and Cartagena are among the Spanish cities lagging behind on air quality, according to a new report by environmental group Ecologistas en Acción. The analysis reviewed data from official air quality monitoring stations in around twenty medium and large cities during 2025 and found that all exceeded the stricter nitrogen dioxide limits set to become law across the European Union by 2030.

Nitrogen dioxide, or NO₂, is a toxic gas produced mainly by vehicle exhausts, particularly in busy urban areas. Long-term exposure can damage the lungs, weaken the immune system and increase the risk of respiratory infections. The European Environment Agency links NO₂ to thousands of premature deaths each year across the EU, including more than four thousand in Spain.

In Murcia, the San Basilio monitoring station recorded an average NO₂ concentration of about 29 micrograms per cubic metre in 2025, well above the future legal limit of 20 micrograms. Although this remains below the current Spanish limit of 40 micrograms, health experts argue that the existing standard is outdated. In Cartagena, campaigners warn that the absence of traffic-focused monitoring stations means official figures may underestimate pollution levels. The regional government says current readings comply with Spanish law and points to plans to expand monitoring and introduce a new Air Quality Strategy for 2030.