May 1 begins the effective regulation of The Mediterranean Emission Control Area for sulphur oxides. This makes the Mediterranean Sea the world’s fifth Emission Control Area (ECA) for sulphur oxides–noxious fumes produced when ships burn fuel oil. Sulphur oxide emissions lead to sea and land acidification and contribute to fine dust, which is linked to respiratory and cardiovascular conditions.
Emission control areas have stricter controls to minimize air pollution from ships. In the Mediterranean Sea, ships will have to reduce the amount of sulphur content in marine fuel from 0.5% (a global requirement) to a maximum of 0.1%. In comparison, the sulphur content in road fuel for trucks or passenger cars is restricted to 0.001%.
Sulphur oxide emissions in the EU have decreased by approximately 70% since 2014, primarily due to the establishment of an Emission Control Area in Northern Europe, as reported in the 2025 European Maritime Transport Environmental Report and the 2025 Zero Pollution Monitoring and Outlook Report.
The new Mediterranean Emission Control Area is expected to lead to further reductions. However, during the same period, nitrogen oxide (NOx) emissions in the EU have increased by 10% from 2015 to 2023, with an 8% increase specifically in the Mediterranean. The European Commission and Mediterranean States are currently assessing the most effective means to reduce these emissions.
The EU and Mediterranean countries agreed in 2021 to set up this emission control area, under the UN’s Barcelona Convention. The International Maritime Organization (IMO) approved it in 2022. In April 2025, the IMO also approved a Northeast Atlantic Emission Control Area to reduce both sulphur and nitrogen oxides, due to be adopted later this year, with entry into effect in 2027. It will encompass the EU littoral states, Greenland, the Faroe Islands, Iceland, and the UK.
“The EU and its Mediterranean neighbours have jointly set up an Emission Control Area to tackle ship pollution at its source. This is a major step towards making our maritime industries cleaner, more competitive, and future-proof,” said Jessika Roswall, Commissioner for the Environment, Water Resilience, and a Competitive Circular Economy. “Preserving this marine region is crucial for water resilience, reducing pollution, and protecting the health of coastal communities and their surrounding environment.”
Since the early 2000s, Emission Control Areas have been established in ecologically sensitive regions, such as the Baltic and North Seas. By 2014, sulphur oxide concentrations around the Emission Control Areas had significantly decreased, benefiting coastal health without significant economic impact on the shipping sector. The EU initiative’s success in the Baltic and North Seas is set to be replicated with the Mediterranean Emission Control Area and the upcoming one in the Northeast Atlantic.
