Ships belching toxic fumes from diesel fuel contribute to the deaths of tens of thousands of people in Europe, Asia and the United States each year, claims a U.S. report released this week.
As many as 60,000 people living in coastal communities along major shipping routes died from lung and heart complaints as a result of high sulfate emissions from ships in 2002, according to the study released Wednesday.
With international maritime trade on the rise and little regulation of ship emissions, that death toll could rise to as many as 82,000 by 2012, says the report to be published next month in American Chemical Society's journal Environmental Science & Technology.
People living in port cities like Hong Kong, Shanghai and Shenzhen were likely to be hit the hardest as most of the pollution occurred within 250 miles of their coasts, said the American researchers.
"Twenty-eight percent of the world's shipping container output passes through Hong Kong and Shenzhen," said Michele Weldon, environmental program manager at Civil Exchange, a public policy think tank in Hong Kong. "The significance of this study — that marine pollution has health impacts — cannot be ignored."
The study's U.S. authors said diesel-powered ships burn some of the dirtiest fuel on the planet today — on average, having almost 2,000 times the sulfur content of highway diesel fuel in the United States and Europe.
While air pollution from diesel trucks and buses has been reduced by more than 90 percent over the last few decades, emissions from ocean-faring ships — using the same diesel engine technology — have risen virtually unchecked, it said.
"Ship pollution affects the health of communities in coastal and inland regions around the world, yet pollution from ships remain one of the least regulated parts of our global transportation system," said Dr. James Corbett, co-author of the report and associate professor of marine policy at the University of Delaware.
"With more than half the world's population living in coastal regions and freight growth outpacing other sectors, shipping emissions will need to meet stricter control targets," he said.
The study was commissioned in part by Clean Air Task Force and Friends of the Earth International, which are negotiating with the U.N. International Maritime Organization for new regulations to reduce shipping emissions.
Weldon said ships could reduce pollution by cutting speeds near shores and switching to cleaner fuels as they approached ports. Already, port cities such as Rotterdam and Los Angeles have imposed their own strict emission standards on ships entering their waters.
Arthur Bowring, of the Hong Kong Ship Owners Association, said voluntary regulation was not the answer as cleaner fuels, such as distillate, were nearly double the cost of the fuel most ships currently use.
"International regulation is the only way to bring in the use of cleaner fuels and ensure there is no competitive disadvantage when using it," he said.
How numbers were crunched
The researchers took estimated seafaring-ship emissions of particulate and other pollutants, including sulfate and nitrous oxide. Using global circulation models, they mapped out how emissions would drift over land. After folding in regional demographic data, such as population density, they pinpointed areas with a higher likelihood of deaths from cardiopulmonary and lung cancer that are attributable to exposure to emissions.
Alexis Lau, a mathematics professor at the Institute for Environment at Hong Kong University of Science and Technology, said the researchers used a standard method to estimate the health impact of pollutants. He said the ACS journal was respected and the estimated deaths the peer-reviewed study attributed to marine pollution were plausible.
The report said East Asia and South Asia were the most heavily impacted, each representing about one-fourth of the global impact.
One-third of all shipping deaths occurred in Europe; about one-tenth of global shipping deaths occurred in North America, the study said.
"There are a lot of observations made from data to suggest a very strong association between sulfur, air pollution, including marine pollution, and premature deaths from respiratory problems like chronic lung failure," T.W. Wong, professor of medicine at the Chinese University of Hong Kong told the AP.
"If ships switched to cleaner fuels, it would help save lives," he said.