How Clean is the Air on Cruise Ships?

­­­For many, a trip on a cruise brings relaxation, wide open seas and clean, fresh air. But, despite the open nature of a cruise ship, the air passengers breathe in may not be as clean as you think. A recent US study suggests that the air on cruise ship decks could potentially be as polluted and harmful as that in large, industrial cities such as Beijing.

Ryan David Kennedy PhD from John Hopkins University, Bloomberg School of Public Health conducted a study on behalf of campaign group Stand.earth, analysing the air pollution levels on board 4 different cruise ships over a 2-year span. He discovered shockingly high levels of particulate matter (PM), which is pollution containing small solids or liquid droplets suspended in the air.

Study findings

The study looked at four different cruise ships: Carnival Liberty, Carnival Freedom, Holland America MS Amsterdam and Princess Cruises Emerald Princess, all setting sail in and around America, Canada and the Caribbean. Over the course of two years, Kennedy measured PM levels on the decks of the ships, checking the bow, stern and track.

The study found that, on average, PM readings were much higher in the stern areas of the ships, compared to the bow. The most significant difference was seen on the Emerald Princess, where the average PM concentration at the stern was 32,628, while at the bow, which is located upwind of the smokestacks, the PM levels were just 5,167 – a shocking difference of 27,461!

Potential health issues

These findings suggest that a PM source, most likely the ship’s exhaust system is contributing to poor air quality on these cruise ships, potentially causing health issues for those on board, particularly cruise staff working near the stern or in the ship’s exhaust system.

According to the report, PM can be dangerous for our health. When inhaled, the small solids and liquid droplets can damage the heart and lungs, potentially causing inflammation of the airways and travelling through the blood stream, impacting other organs. Despite the ships being on open water and in open air, those on board could be being exposed to potentially dangerous levels of PM, threatening their health if exposure is prolonged.

Carnival, the company behind the four cruise ships, disagrees with Kennedy’s findings, however, dismissing them as “fake tests that really have no scientific basis”. They argue that the air quality of their ships “meet or exceed every requirement” and that they work with “national and international regulatory bodies to ensure the utmost safety of our guests and crew”.

Of course, there are more environmental issues with water than ships alone. With sea levels rising, flood control is one of the biggest issues facing countries across the world today. Find out more in the article ‘The Challenges of Flood Control’.