Air Quality on Cruise Ships As Bad As "World's Most Polluted Cities"

Taking a cruise is supposed to be a relaxing experience and definitely not something that you'd expect to be harmful to your health. But, according to a new report from a Johns Hopkins University researcher, the air quality on cruise ships can be up to five times worse than some of the world's most polluted cities. 

The study examined the concentrations of so-called ultrafine particulate matter on the decks of the four Carnival Corp cruise ships over a two-year period. Researchers found that the concentrations of the particulate matter aboard four major cruise ships ranged from more than 45,000 particles per cubic centimeter on a Carnival vessel, to a staggering 157,7000 particles per cubic centimeter on a Princess Cruises Ship. 

To compare: air quality on the the streets of Beijing - considered one of the world's most polluted cities - reached about 30,000 particles per cubic centimeter. 

Ryan Kennedy, the author of the report and an assistant professor at Johns Hopkins University Bloomberg School of Public Health, says the pollution in and around cruise ships is "dangerous" and "not a healthy thing for us to be exposed to."

Ships exhaust can contain several harmful properties, including metals and polycyclic aromatic hydrocarbons, many of which are considered toxic and/or carcinogenic. 

Kennedy took his measurements for the report on four different ships including; the Carnival Liberty, the Holland America MS Amsterdam, the Carnival Freedom, and the Emerald Princess. Levels of particulate matter in the atmosphere were measured using a P-TRAK Ultrafine Particle Counter while the ships were both docked and moving at sea. Kennedy says he took his measurements without the knowledge of the cruise line or crew. 

The highest concentrations of particulate matter was found where you would expect it to be - located behind the vessel's smokestack at the back of the ship. The air was clearer the closer you got to the bow - or front of the ship for all you landlubbers. 

In a statement Carnival says that it has always coordinated its cruises with international regulatory bodies like the Environmental Protection Agency in the United States and dismissed the report. 

"Independent testing on our funnels -- which is the area where the exhaust originates -- further validates our claims," the company said. "This particular organization, for fund raising purposes, is constantly in search of a problem in our industry even if it has to create fake tests that really have no scientific basis."

In 2013, Carnival agreed to reduce the pollution generated by its cruise ships in a deal with the EPA and Coast Guard. The cruise line was tasked with developing new technologies that would allow the shipping industry comply with stricter air quality standards. 

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