Water pollution is not the only type of environmental waste generated from cruise ships. These massive liners are also sources of major air pollution.

According to a study by the University of California, San Diego, the harm from cruise ship air pollution is real and potentially dangerous to human health.  Dirty smoke from ships that burn high-sulfur fuel contain sulfur-rich matter fine enough to accumulate in the air.

Mark Thiemens, the Dean of the Division of Physical Sciences and professor of chemistry and biochemistry at UCSD, was in charge of the research team that conducted the study. “This is the first study that shows the contribution of ships to fine particulates in the atmosphere,” says Thiemens. “Ships are really unregulated when it comes to air pollution standards. What we wanted to find out was the contribution of ships to the air pollution in San Diego. And what we found was a surprise, because no one expected that the contribution from ships of solid sulfur-rich particles called primary sulfate would be so high.”

According to an online entry for the journal Proceedings for the National Academy of Sciences, this filthy smoke can account for up to one half of the dangerous sulfur-rich particles in the air on given days. These findings by chemists from the University of California, Berkeley, have especially dire implications for the state of California. California’s coastal waters accommodate cruise ships, tankers, and cargo ships on a daily basis.

“Some researchers have estimated [dirty smoke from ships] may be responsible for as many as 60,000 deaths worldwide at a cost to the U.S. economy of $500 million a year,” says an article for Eureka! Science News.

“Bunker oil,” the industry term for the type of fuel used to power ships, is released as sulfur dioxide (SO2) during the burning process. SO2 is a gassy pollutant that accumulates in the atmosphere. Their microscopic nature is particularly harmful to humans because they are able to travel long distances and remain in the atmosphere for longer periods of time. Since these particles are much smaller than the dust grains humans are accustomed to breathing, they also remain in the lungs once inhaled.

One of the major findings of the study is the discovery that smoke from ships contributed as much as 44 percent of the air-borne sulfate in the atmosphere of the California coastal areas.

“And because a large part of the world’s population live in major cities with shipping ports - such as New York City, San Francisco, Hong Kong, Houston, and Singapore - and global shipping is expected to increase in the decades to come, this [study] should help policy makers around the world make more informed decisions about improving the health of their citizens,” says Thiemens.

Resources:
http://www.esciencenews.com
Proceedgins of the National Academy of Sciences
University of California, San Diego