Air Date: Week of May 24, 2002

A report from the National Academy of Sciences examines the problem of oil in our oceans. How much is there, where is it from, and what does it do? Anna Solomon-Greenbaum highlights the report’s findings.

Transcript

CURWOOD: Closer to home, the National Academy of Sciences has released a report it calls "Oil in the Sea." A key finding, some 29 million gallons of petroleum enter North American ocean waters every year as a result of human activity. But the sheer volume of oil is only part of the story.

Much of the Academy report tells where the oil comes from, and what happens to it when it gets into the ocean. Living on Earth’s Anna Solomon-Greenbaum has details.

SOLOMON-GREENBAUM: The results of the Academy’s research may surprise the average person who probably thinks "Exxon Valdez" when the words "oil" and "ocean" are mixed. The report finds tanker spills and pipeline leaks are responsible for less than 10% of the oil released by humans into the oceans each year. Most of the oil, 85% of it, comes from seemingly minor sources, like your uncle’s outboard motor, the oil that drips from your car, or the fuel that’s dumped by airlines.

In the past, the impact of these various sources has been hard to measure, and not nearly as dramatic as blackened shorelines and dead birds left by a major oil spill. Dan Walker, staff scientist on the Academy report, says the little spills are more significant than imagined.

WALKER: We’re talking about a few ounces each year that each one of us accidentally release. But there’s a lot of us, and it tends to accumulate. And what we’re seeing is, is that, in many cases, there seems to be a clear-cut relationship between these low concentrations of some of these toxic compounds, and adverse effects on marine organisms.

SOLOMON-GREENBAUM: Walker says oil companies have dramatically reduced the amount of oil spilled from tankers, wells and pipelines. And the industry says their operations are safer than ever before. But environmental groups warn vigilance is still needed.

SPEER: How much oil is only one part of the equation?

SOLOMON-GREENBAUM: Lisa Speer is a senior policy analyst at the Natural Resources Defense Council. The Academy’s report, she points out, finds even a small spill can have a big impact if it ends up in a sensitive ecosystem. Speer says land runoff is the number one source of coastal pollution in America, and she’s glad to see it getting more attention.

SPEER: But that doesn’t mean that we can ignore the threats posed by offshore oil and gas development and transportation in sensitive areas. We need to do these things together. And we need to keep working towards reducing pollutants that get into our oceans, both through land-based runoff, as well as through major oil spills.

SOLOMON-GREENBAUM: Both land-based runoff and oil spills at sea are dwarfed by a third source of oil in the oceans, natural seeps from the seabed. Their impact is unique, according to Dan Walter, because organisms living near these seeps have, for the most part, adapted to the toxic compounds that petroleum unleashes in their ecosystem. Still, Walker says, natural seeps can make good study sites for scientists trying to understand the slow, subtle effects of oil from land-based runoff.

WALKER: That gives us a little bit of a idea of how the introduction of large amounts of petroleum, a little bit at a time, small dribs and drabs, but everyday, over the course of many, many years, how that can effect an ecosystem.

SOLOMON-GREENBAUM: Policymakers have been exploring ways to control runoff. So far, most of their effort has focused on nutrient runoff from pesticides and waste. The Academy’s report may raise the profile of petroleum runoff as another part of the problem. For Living on Earth, I’m Anna Solomon-Greenbaum in Washington.