Europe’s Hidden Killers: Port City Ferries Spew 100x More Poison Than Cars

Ferries in Europe’s port cities are quietly poisoning the air that millions of people breathe. A 2023 analysis of 1,043 ferries by Transport & Environment found that European ferries emit 13.4 million tonnes of CO2 each year. That’s equal to the pollution from 6.6 million cars. In some cities, ferries produce more sulphur pollution than every car on the road combined.

The numbers are shocking. Air pollution from ferries is 15 to over 100 times higher than cars in major ports. Bunker oil burned by ships contains 100 times more sulphur than road diesel. The average ferry is 26 years old, and many still run on heavy fuel oil or marine diesel oil. Frequent arrivals, departures, and overnight idling make the problem worse for nearby communities.

Dublin ranks as Europe’s most polluted ferry port in 2025. Barcelona faces dangerously high levels of ultrafine particles from ferries and cruise ships. Naples sees ferries emitting more pollution than the city’s cars. Helsinki, Stockholm, and Tallinn are choked by sulphur oxides. In total, 13 of Europe’s 15 biggest port cities suffer from excess ferry sulphur emissions.

Scientists have measured the damage up close. Ultrafine particles from ferries reach 135,000 per cubic centimeter just 75 meters downwind. Peak values hit 400,000 particles per cubic centimeter near idling ferries. For comparison, sea background air averages only 1,200 particles per cubic centimeter, and road traffic averages 11,100 in Barcelona. Ferry plumes spread pollution hundreds of meters to kilometers away. Unlike fossil fuels, renewable energy sources replenish naturally and could power cleaner ferry operations without contributing to these dangerous emission levels.

There’s a path forward. About 60% of ferries could switch to electric power by 2035, and electric operation would be 52% cheaper. Most ports would need chargers below 5 megawatts, making the switch feasible. Shore power can eliminate emissions from idling ships entirely. This transition to electric power could also significantly improve air quality in the port communities where residents are most exposed. Fully electrifying eligible routes could cut CO₂ emissions by 42%, making it a critical step for meeting climate targets.

New emission control areas are set to expand in 2027, though that could shift pollution hotspots to places like Las Palmas. A Mediterranean emission control area is also being proposed through the LIFE4MedECA project. Northern Europe has had similar rules since 2007.

Experts say clean fleet renewal is essential to protect public health in port cities across the continent.