Parts of Europe are suffering through the second heatwave of the year leading to dangerous spikes in ground-level ozone pollution with devastating consequences for human and environmental health, warns the European Environmental Burea, Europe’s largest network of environmental NGOs.
Extreme temperatures have serious health repercussions but the impacts of a photochemical smog, which forms as a result of ground-level ozone pollution, remains little known. In 2022, exposure to ozone pollution, driven largely by methane from industrial agriculture practices, led to an estimated 70,000 premature deaths and €2 billion in crop losses across the EU.
As scientists warn of a ‘super El Niño’ this summer – a natural phenomenon that occurs every few years and pushes up global temperatures – ozone levels are already breaching EU air quality standards (anything above 120 mg/m3) and endangering human lives.
Heatwaves exacerbate the problem, leading to breaches of the alarm level threshold (beyond the 240 mg/m3). Current health protection measures set a maximum daily eight-hour mean of 120 micrograms per cubic metre (µg/m3) not to be exceeded more than 18 times per calendar year.
In 2024, 77.4% of EU measuring stations exceeded this limit. This rose to 85.4% in 2025, with the Lombardy region of Italy one of the hardest hit regions, with EEB member Legambiente Lombardia reporting 6 alarm breaches by June 2025, as reported by EEB in 2025.
This year, Legambiente Lombardia already raised the alarm in May as the Po Valley experienced dangerous breaches of the EU threshold. The toll that methane and ozone is having can be explored across Member States in this interactive map released by Ricardo in February 2026.
