Environment & The Green Beat

SAN FRANCISCO (AP) ― Sticky, packed with pollutants and slow to break down, the type of oil spilled into the San Francisco Bay by a cargo ship is an environmental nightmare loose on the waves, said environmentalists calling for a ban on it.

"Bunker fuel is the dirtiest fuel on the planet," said Teri Shore, campaign director for the marine program at Friends of the Earth. "Ships are being used as waste incinerators for the oil industry."

On Sunday, the group launched a petition asking Congress to ban bunker fuel use. About 5,000 people had signed onto it by Monday.

About 58,000 gallons of the fuel poured into the San Francisco Bay last Wednesday, when the ship sideswiped a support on the San Francisco-Oakland Bay Bridge, opening a 90-foot gash on the side of the 926-foot vessel and tearing open two of its fuel tanks. The spreading oil has fouled nearly two dozen beaches and killed dozens of sea birds.

The problems posed by bunker fuel to the environment stem from its physical properties—it's gooey and thick, particularly in cold water—and from the toxins it carries, scientists said.

A byproduct of oil refining, a process that separates lighter, cleaner, more commercially valuable liquids like gasoline and kerosene, bunker fuel is a black, viscous substance laden with heavy metals, sulfur and other polluting chemicals.

"If it's too thick and too complex to combust in an engine, we make tar out of it, but if it's still able to be heated and to flow through a pipe, we call it bunker fuel," said James Corbett, a professor at the University of Delaware's College of Marine and Earth Studies.

Its main advantage to the shipping industry is that it's cheap— a cost-effective option for massive ship engines can burn fuels other engines can't use, industry representatives said.

But if bunker fuel spills, it gums up beaches, marshes and other ecosystems. Animals take it for food or ingest it as they try to clean their coats, and the oil breaks through the waterproof fur or feathers that keep them dry, exposing them to hypothermia, said Gary Shigenaka, with the emergency response division of the National Oceanic and Atmospheric Administration.

The fuel also can break up into tar balls, which create a weathered coating on the outside and keep the oil fresh on the inside. Those can travel far and plague wildlife and ecosystems for years, Shigenaka said.

Bunker fuel also creates problems in the air when burned.

Tiny particles of pollution and chemicals released through ship exhaust were linked to the premature death of about 60,000 people with heart and lung ailments in 2002, according to an article published this month in Environmental Science & Technology, the journal of the American Chemical Society.

"If the fuel burned by ships were cleaner, we would prevent a significant number of deaths annually," said James Winebrake, professor at the Rochester Institute of Technology who co-authored the study with Corbett.

Winebrake noted that diesel sold for road use in the United States has about 15 parts of sulfur per million, while the average sulfur content of bunker fuel globally is about 27,000 parts per million.

Some steps have been taken to cut down on ship pollution in California, in part because of pressure from environmental groups.

Air regulators required ships coming within 24 miles of the state's coastline to burn low-sulfur fuel, but that provision has been challenged in court by industry groups.

The ports of Los Angeles and Long Beach, two of the country's largest, have encouraged approaching ships to slow down to reduce emissions. They're also putting in equipment to let ships plug into land-based electrical outlets and turn off their engines while docked.

But environmental groups argue that it's time to make significant changes, such as phasing out bunker fuel altogether, not just small steps that would allow its continued use. With the growth of global trade, traffic of huge cargo ships around the world is on the rise, and with it, the impact of their emissions, they said.

"There are more ships on high seas, more ships coming into the bay," Shore said. "That means more potential for accidents and more exposure to pollution."

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