Passenger and cargo ferries are responsible for more air pollution than all the cars in major cities like Barcelona, Dublin or Naples, according to a report from an environmental group.

Helsinki, Stockholm and Tallinn are among 13 of Europe’s 15 biggest port cities choked more by sulphur oxides (SOx) from ferries than road vehicles, Transport & Environment (T&E), a clean transport advocacy group, told the Guardian.

Dublin is currently the most polluted port city in Europe when it comes to ferry air pollution, followed by Las Palmas and Holyhead. This is set to change in 2027, when new emission control areas will come into place, limiting the air pollution from maritime fuels in the North-East Atlantic. Even with similar measures already in place in the Mediterranean, in cities like Barcelona, ferries pollute 1.8 times more SOx than all the city’s cars.

T&E says Europe’s ageing fleet of nearly 2,000 ferries are a large but overlooked source of foul air in coastal cities.

The report from T&E also found ferries to be a bigger polluter than cars in Athens and Rome, which did not feature in the ranking because their ports are considered separate cities, and in Valletta, the tiny capital of Malta.

“Ferries should connect communities, not pollute them,” said Felix Klann, Shipping Policy Officer at T&E, in the March 3 report. “Too many ferries are burning polluting fossil fuels, pumping toxic air into Europe’s port cities. Electrifying them could dramatically cut emissions and bring a breath of fresh air to millions of people.” 

According to the Guardian, Sotiris Raptis, secretary-general of the European Community Shipowners’ Association, said the EU had introduced ambitious policies to support electrification — including a requirement for passenger and container ships to use electricity in ports by 2030 — but that “enormous” investments were needed to finance the energy transition in shipping.