10:42 a.m., July 8, 2009----Most oceangoing ships use high-sulfur fuels, which emit particles into the air that can cause lung and heart disease and harm the environment. International policymakers concerned about the effect of those fuels on human health are seeking solutions. But which approach would be the most effective?
A new study from the University of Delaware and Rochester Institute of Technology will help shape their answer to this question.
The study, published in the July 1 issue of Environmental Science & Technology, found that placing no controls on ships' sulfur emissions would result in approximately 87,000 premature deaths worldwide in 2012 alone. This number is an update on the estimate from a widely reported 2007 ship mortality study by the same research team, which estimated that shipping-related particulate matter emissions are responsible for approximately 60,000 cardiopulmonary and lung cancer deaths annually.
The team's latest study, however, goes a step further. It takes into account the fact that policymakers are considering regulating harmful air emissions from ships in one of two ways: by restricting global sulfur content levels or by designating emission control areas to reduce impacts to sensitive coastal regions and communities.
The researchers found that requiring ships globally to reduce fuel sulfur content to 0.5 percent would reduce premature deaths by about 41,200.
Requiring ships to use marine fuel with 0.5 percent sulfur within 200 nautical miles of coastal areas, they found, would reduce premature deaths by about 33,500. Limit the percent of sulfur to 0.1 percent within 200 nautical miles of the coast, and the number of premature deaths would be reduced by a total of 43,500.
“This study of health-based impacts to coastal populations around the globe shows that real health benefits are associated with cleaner fuels producing lower particle emissions from ships,” said James Corbett, professor of marine policy at UD's College of Earth, Ocean, and Environment (CEOE) and one of the study's two lead authors.
Current fuel sulfur content averages about 2.4 percent, with upper limits as high as 4.5 percent. The International Maritime Organization (IMO), the United Nations' specialized agency responsible for improving maritime safety and preventing pollution from ships, has agreed to set the global fuel sulfur cap at 3.5 percent in 2012 and 0.5 percent as early as 2020.
“Our scenarios reflect policy proposals submitted to the IMO by various countries, such as the U.S. and Canada,” said co-author James Winebrake, professor of science, technology, and policy at the Rochester Institute of Technology. “This new study demonstrates the human health benefits associated with these types of policies.”
The study analyzed ship emissions' health impacts by integrating global ship inventories, climate models, population models, and health impacts functions. It was supported by the Oak Foundation, the German Helmholtz-Gemeinschaft Deutscher Forschungszentren, and the German Aerospace Center within the Young Investigators Group SeaKLIM. Additional support was provided by the Sustainable Intermodal Freight Transportation Research Program, a multi-university initiative led by Corbett and Winebrake.
To learn more about UD's College of Earth, Ocean, and Environment, visit the Web site.