The study was based on information from nearly 500 stations across Spain, 20 of them in Aragón. Ground-level ozone is formed by the combination of other pollutants in the presence of solar radiation and is particularly associated with the spring and summer months, when high temperatures and intense sunlight encourage its accumulation.
According to the organisation, 2026 brought especially favourable conditions for this phenomenon. A very warm spring was followed by the hottest summer in at least the past century and a half, marked by four intense heatwaves and numerous wildfires during July and August, circumstances that favoured ozone formation.
OZONE LEVELS IN ARAGÓN REACH HIGHEST POINT SINCE 2010
Levels recorded this year were the highest in Aragón since the current legal limits came into force in 2010. Ecologistas en Acción puts the increase in breaches of the legal target for health protection at 53% compared with the average recorded between 2012 and 2019, before the pandemic.
Using the World Health Organization's recommendations as a reference, the report concludes that ozone pollution affected the entire population of Aragón in 2026. However, no population was found to have been exposed above the current legal target, which sets less stringent levels than the WHO's health guidelines.
The situation changes when the new legal target approved by the European Union for 2030 is applied. The Pyrenees and the Ebro Valley failed to meet this threshold at least one station during the 2024-2026 period. The two areas are home to nearly half a million people, approximately one-third of Aragón's population.
CALL FOR A PLAN TO REDUCE OZONE POLLUTION
Ecologistas en Acción believes that a significant share of the pollution affecting these areas comes from emissions from traffic in Zaragoza and on the main roads in the Ebro Valley. It is therefore calling on the Government of Aragón to urgently draw up a regional plan to improve air quality by reducing ozone pollution, a plan that has been pending for years.
The organisation also warns of the health consequences associated with this pollutant. According to European Environment Agency data cited in the report, exposure to ozone could be linked to as many as 300 deaths each year in Aragón, with children, older people, pregnant women and those with cardiorespiratory diseases facing particular risk.
The proposed measures include reducing motorised traffic, promoting energy conservation, limiting industrial emissions and using tax measures to discourage diesel vehicles. The organisation also proposes regulating the development of renewable energy and imposing a moratorium on new mega-farms, with the aim of reducing the pollutants involved in ozone formation.
