Palma, behind only Barcelona for cruise-ship contaminants. | Gabriel Alomar

An analysis by Transport & Environment indicates that Palma has the second highest level of contaminants caused by cruise-ship emissions in Europe. Barcelona has the highest, Valencia is third, followed by Civitavecchia (Rome) and Southampton.

Also known as the European Federation for Transport and Environment, its study - based on 2017 data - establishes that cruise ships in Palma emitted ten times more sulphur oxides than cars. Spain is one of three countries with the highest levels of sulphur oxide pollution - Italy and Greece are the others.

The study has also looked at the impact of specific cruise operators. Carnival Corporation, it is said, emitted ten times more sulphur dioxide in coastal areas of Europe than the total of 260 million cars in the European Union plus Norway, Iceland, Greenland and Montenegro. Royal Caribbean produced four more times the pollution.

Faig Abbasov, for Transport & Environment, says that cruise ships are floating towns powered by the dirtiest fuel possible. Cities in Europe are seeking to prohibit contaminating diesel vehicles but are at the same time giving "a free pass" to cruise operators and toxic gases.

In terms of nitrogen oxides, the analysis indicates that 87 cruise ships in Palma in 2017 emitted gases equivalent to 56% of those by 245,000 cars.