As of May 1, 2025, the Mediterranean Sea has officially become an Emission Control Area (ECA) for Sulphur Oxides and Particulate Matter under MARPOL Annex VI. Ships operating in this region must adhere to a strict limit on sulphur content in fuel oil, capped at 0.1%. This regulation marks a significant step forward in reducing air pollution, thereby providing notable health benefits for humans as well as positive impacts on the marine environment.
The regulations enforce stringent measures to prevent and control air pollution linked to shipping. The new ECA compliance necessitates tighter sulphur limits compared to the global standard, which allows a maximum of 0.50% mass by mass (m/m) outside these designated areas. The rigorous controls aim to cut down on emissions that pose risks to public health.
Reducing sulphur oxide (SOx) emissions from maritime activities is expected to decrease occurrences of lung cancer, cardiovascular diseases, strokes, and childhood asthma. Additionally, the environmental effects are profound as this reduction helps combat acidification that threatens crops, forests, and aquatic life. Moreover, less haze generated by shipping activities will enhance visibility and reduce the likelihood of maritime accidents.
The Mediterranean Sea is a critical hub for global maritime trade, facilitating around 20% of seaborne trade and hosting more than 17% of global cruise operations as well as 24% of the world fleet. The Med SOx ECA joins the ranks of other established emission areas, including the Baltic Sea, North Sea, North American area, and the Caribbean Sea. With ongoing developments, two additional ECAs were designated in 2024, covering the Canadian Arctic and the Norwegian Sea.
Recently, the North-East Atlantic was also proposed as a new ECA in April 2025. Notably, changes in sulphur content regulations in January 2020 have already led to a considerable reduction—70%—in overall SOx emissions from global shipping.