The air on cruise ships is at times as polluted as in major cities, according to new research.
Measuring the levels on four large cruise ships between 2017 and 2018, the study by researchers at John Hopkins University in Baltimore, US, claims that the concentration of particulate matter (PM) pollution was comparable to that measured in polluted cities, including Beijing and Santiago.
The study defined particulate matter pollution as small solids or liquid droplets suspended in the air.
In the report, author Ryan David Kennedy, an assistant professor at the Maryland university’s Bloomberg School of Public Health, writes: “Despite being on the open water and in open air, vacationers and cruise ship staff may be exposed to elevated concentrations of PM.”
According to the report, ship exhaust contains harmful constituents, including metals and polycyclic aromatic hydrocarbons (PAHs), many of which have toxic, mutagenic and carcinogenic properties.
The report says the study suggests “that patrons and staff who are in the aft areas of cruise ships… are likely exposed to elevated levels of particulate matter, and that some of the particulate matter observed in this study was likely generated by shipping exhaust. This raises health concerns, given that ship exhaust is known to contain such dangerous constituents as metals and PAHs.”
The tests were carried Carnival, Holland America Line and Princess Cruises ships (Holland America Line and Princess Cruises are subsidiaries of Carnival Corporation).
In 2018, the Cruise Lines International Association (CLIA) made a global commitment to reducing the rate of carbon emissions across the industry fleet by 40 per cent by 2030.
Andy Harmer, Cruise Lines International Association (CLIA) UK and Ireland director, said: “Cruise ships are one of the more high-profile and easy-to-target flashpoints when air pollution and emissions are discussed. The cruise industry is only a small part of this issue, an issue which is facing the wider tourism and shipping sector; but we want to be a large part of the solution.
“Globally, the cruise industry has already invested $1billion in new technologies and cleaner fuels, to significantly reduce ships’ air emissions. Looking ahead, the industry has committed more than $8 billion to construction of highly advanced LNG-fueled cruise ships, which will have even lower emissions and higher energy efficiency.”
Roger Frizzell, senior vice president and chief communications officer of Carnival Coroporation, told Telegraph Travel: “We have installed Advanced Air Quality Systems on nearly 80 per cent of our global fleet in close coordination with the EPA [Environmental Protection Agency, an agency of the United States Federal Government] so these systems are environmentally friendly, in addition to rolling out new ships powered by LNG [liquefied natural gas], the cleanest burning fuel available, so their study is misleading and inaccurate.
“We are tested regularly by authorities around the world, such as the EPA, in order to be approved to sail in key ports.”
In the study, Mr Kennedy took pollution measurements in front of and behind smokestacks on two Carnival Cruise Line ships (Carnival Liberty and Carnival Freedom), a Holland America Ship (MS Amsterdam) and a Princess Cruises ship (Emerald Princess) using a P-TRAK Ultrafine Particle Counter. On each ship, the highest average measurements of particulate matter (PM) concentration were behind the smokestacks, at the back of the ship. On each ship tests were undertaken over a five to eight day period, according to the report.
Emerald Princess was found to have the highest average particulate matter pollution, in measurements taken in front of and behind the smokestacks.
Measurements were taken when the ships were docked and while at sea and without the knowledge of the cruise lines or staff. The four ships included in the study all entered service between 2000 and 2007.
Carnival Corporation said in a statement: “These so-called fly-by tests are completely ridiculous, inaccurate and in no way represent reality. We test the air quality of our ships and they meet or exceed every requirement.
“The air quality on our ship decks when in port compares favorably with a typical urban or suburban environment. Independent testing on our funnels – which is the area where the exhaust originates – further validates our claims […] The safety of our guests is our top priority and we undertake our cruises in close coordination with national and international regulatory bodies like the EPA to insure the utmost safety of our guests and crew.”
Cruise ship technology has sought to reduce carbon emissions. Expedition cruise company Hurtigruten, for example, will add MS Roald Amundsen, the world’s first hybrid cruise ship, to its fleet this year. It will cut emissions by sailing with electric propulsion. The engines will normally run on low-emission diesel but can be topped up with electricity from a huge battery pack, cutting fuel consumption by up to 20 per cent.