What are those container ships and oil tankers I see passing by every day doing to my city”s air quality?

What are those container ships and oil tankers I see passing by every day doing to my city”s air quality?

—via email

Large marine vessels such as container ships and oil tankers are among the least-regulated sources of air pollution in the United States. Though they are more fuel-efficient than other forms of commercial transportation, most burn the cheapest diesel, called bunker oil, which is generally prohibited from being used by other industrial applications due to the high levels of extremely toxic compounds it releases when burned. In addition, commercial ships release 30 percent of the globe”s nitrogen oxide emissions and 16 percent of sulfur emissions.

And those numbers will only increase, says the San Francisco-based Blue Water Network, a non-profit clean-water advocacy group: “As more consumer goods are imported from Asia, cargo shipping is expected to double or even triple by 2020—especially in high-traffic ports such as Oakland, Los Angeles and New York. As marine traffic increases, so does the threat to our oceans, marine life and public health. Air pollution from all ocean-going vessels in U.S. waters is expected to grow by 150 percent over the next three decades.”

Currently, more than 60,000 ships sail in and out of U.S. ports every year, and for cities trying to clear their smoggy air, cargo ship pollution can actually negate clean air gains. The Santa Barbara County Air Pollution Control District found that even without a port in the county, air-quality gains from reducing car and truck emissions would be wiped out by passing ships commuting to the nearby ports of Los Angeles and Long Beach. “Just one container ship traveling one mile produces nitrogen oxide emissions equaling 25,000 cars traveling the same distance,” explains Anthony Fournier of the District.

The U.S. Environmental Protection Agency (EPA) has started to regulate pollution from American ships, but since a vast majority of the ships that come into port are foreign, international standards are needed, says Bluewater, which is suing the EPA to institute stronger rules governing pollution from ships. “These ships run on the dirtiest fuel available,” says Martin Wagner, an attorney with the non-profit public interest law firm, Earthjustice, which is representing Bluewater. “The EPA”s failure to regulate their emissions undermines the efforts of coastal communities from Los Angeles to Boston to protect public health and meet federal clean air standards.

CONTACTS: Bluewater Network, (415) 544-0790, www.bluewaternetwork.org; Santa Barbara County Air Pollution Control District, (805) 961-8800, www.sbcapcd.org; U.S. Environmental Protection Agency, www.epa.gov; Earthjustice, (415) 627-6700, www.earthjustice.org.