Air pollution originating from ships may be more harmful than emissions from road traffic, according to research conducted by a team of 32 scientists in Southampton. The study, which began in 2018, investigated air pollution from the city's docks, a major UK port that saw over 2.5 million cruise passengers in 2025.
The researchers found that ultrafine particles in cruise ship emissions, containing metals such as vanadium, nickel, cobalt, and molybdenum, were associated with increased inflammation in lung cells. These particles also appeared to reduce the cells' ability to prevent the replication of viruses.
Professor Matthew Loxham, the project leader from the University of Southampton, stated that the ultrafine particles in ship emissions were more capable of driving cells to release chemical communication signals linked to inflammation and diminishing their viral resistance. Further tests suggested that vanadium particles were responsible for these effects, with a clear link between ultrafine vanadium downwind of the cruise terminal and the number of cruise ships present.
Dr Nat Easton, a researcher on the team, noted the significantly higher levels of vanadium and nickel in cruise ship-associated particles compared to those from container ships. Associated British Ports (ABP) expressed concerns regarding the study's methodologies and the strength of some findings presented to the media. ABP also highlighted that Southampton is the first UK port to introduce large-scale shore power connections, with approximately 15% of cruise ships now using this technology.
Currently, there are no routine measurements for ultrafine particles or vanadium spread from the port. A new EU directive will mandate ultrafine particle measurements around pollution hotspots, including ports, but this does not apply in the UK.