Air quality of cruise ships is as polluted as smog-damaged cities in Beijing and could endanger human health, according to a new study.
Researchers observed levels of debris pollution on four different cruise ships over a two-year period.
They found that air quality was "comparable to concentrations measured in contaminated cities," and inhaled could "damage the heart and the lungs."
A new study argues that the air quality of cruise ships is as polluted as Beijing
The study was conducted on behalf of the StandEarth Campaign Group by Dr. Ryan David Kennedy of Johns Hopkins University, Bloomberg School of Public Health in Baltimore.
Dr. Kennedy boarded four carnival cruise ships and testified to the air quality of each of them.
The ships were from Carnival Liberty, flying from Florida to the Bahamas; Carnival Freedom, flying from Texas to the Caribbean; Holland America MS Amsterdam travels from Vancouver to Los Angeles; and Princess Cruise Emerald Princess on her way from Los Angeles to Mexico.
Working undercover, Dr. Kennedy measures particulate matter (PM), a term used to describe the mixture of solids and liquid droplets in the air. It can either be made by man or naturally.
He has taken testimony of various parts of the ship, including the nose, the stern and the track, using the ultra-fine particle counter P-TRAK.
The report claims that they show the highest readings often in the back of the ship where the open pools are usually found.
Dr. Kennedy writes: "The average PM values in the stern areas of each ship were significantly higher than the mean values measured in the front of the smoke.
"The results of this study show that a source of AF – possibly partly from the exhaust system of the ship – contributes to the worse air quality in the stern portions of these cruise ships.
Researchers have found that cruise air quality is "comparable to the concentrations measured in contaminated cities," and inhaled can "damage the heart and the lungs."
"The PM concentrations on the decks of these ships are comparable to the concentrations measured in contaminated cities, including Beijing and Santiago.
"Even though they are outdoors, tourists and cruise ship personnel may be exposed to increased concentrations of PM."
After analyzing the completed study, Kendra Ulrich, senior shipping agent at Stand.earth, said: "Extremely high levels of air pollution measured on the carnival corporation's ships indicate that this pollution can pose a serious risk to the health of passengers, staff and people living in the port and coastal communities.
The most shocking finding of this study is that pollution is often the highest near the stern of ships where passengers are encouraged to train.
"This study should be a warning sign for anyone considering cruise reservations, but especially for vulnerable groups such as adults and children or anyone with cardiovascular problems."
The International Cruise Line Association returned to the report and said the cruise ship was an "easy target" when it comes to air pollution
However, a Carnival spokesman criticized the report and told MailOnline Travel: "These so-called fly-tests are completely funny, inaccurate and in no way represent reality.
"We check the air quality of our ships and they meet or exceed any requirement.
"The air quality of our ship's decks, when in the port, compares favorably with the typical urban or suburban environment. Independent tests of our funnels – that's where the exhaust comes from – further confirm our claims.
"This particular organization, for fundraising purposes, is constantly looking for a problem in our industry.
"The safety of our guests is our top priority and we take our cruises in close coordination with national and international regulatory bodies like EPAs to ensure maximum safety for our guests and crew."
Meanwhile, Megan King, a spokesman for the International Cruise Line Association, added: "Cruise ships are one of the most important and easy-to-navigate points of ignition when discussing air pollution and emissions.
"The cruise industry is only a small part of this issue, a matter for the broad tourism and shipping sector; but we want to be a big part of the solution.
"Worldwide, the cruise industry has already invested $ 1 billion in new technologies and cleaner fuels to significantly reduce air emissions in ships.
"In the industry, the industry has taken over $ 8 billion to build high-tech LNG cruise ships that will have even lower emissions and higher energy efficiency.
"The cruise remains committed to continuous improvement and is continuously updated to identify and install new technologies."