Some cruiseships are responsible for pollution levels that are higher than in the world’s most polluted cities, an investigation by Channel 4's Dispatches has found.

In an undercover investigation broadcast on UK TV yesterday, a vessel owned by Carnival Corp’s British brand P&O Cruises was found to emit high levels of “ultra-fine particles”.

Dispatches used a P-Trak ultra-fine particle counter on the 77,499-gt Oceana (built 2000).

The measurements showed that the air on the deck downwind of, and directly next to, the ship’s funnels, had 84,000 ultra-fine particulates per cbm.

This number was even higher next to the funnels on the deck, reaching a peak 226,000.

This is more than double the average found in London’s Piccadilly Circus, where Dispatches recorded 38,400 ultra-fine particulates per cbm.

"Similar to Shanghai and Delhi"

Matthew Loxham, future leader fellow in air pollution toxicology at the university of Southampton, told Dispatches: “These are levels that you would expect to see in the most polluted cities in the world like Shanghai, Delhi and so on.”

In response to Channel 4’s investigation, P&O Cruises issued a statement that was also provided to TradeWinds.

P&O said: “Since 2005 we have reduced our fuel consumption by some 28% with the accompanying reduction in air emissions.

“We continue to invest heavily in environmental technology for Oceana and for all ships across the fleet.

“In keeping with this environmental strategy, exhaust gas cleaning systems will be fitted on Oceana in dry dock later this year.”

Cruise lines under scrutiny

This is not the first time that the cruiseship industry has come under scrutiny from European TV programmes over air pollution.

Earlier this year, a French TV programme unveiled high levels of harmful particles in the air after conducting tests on a European cruiseship.

Daniel Rieger, transport policy officer of German environment association NABU, told Dispatches: “Ships cause not only greenhouse gas emissions but also sulphur oxides, nitrogen oxides and particulate matter.

“Per day one cruiseship emits as much particulate matter as a million cars.

“So 30 cruiseships pollute as much as all the cars in the UK.”

P&O Cruises added: “Cruise lines comprise less than 1% of the global commercial maritime industry of more than 50,000 commercial maritime vessels.

“Carnival has an ambitious programme to install exhaust gas cleaning systems – so-called ‘scrubber technology’ - across its fleet.

“So far, systems are installed on 60 ships across its brands with a further 25 ships to be certified by 2020 in a $400m investment.”