Wednesday, November 10, 2010

Oil in plankton in Gulf of Mexico

A new study found oil in plankton from the Gulf of Mexico.

Does this mean that we're all gonna die tomorrow if we eat a fish from the Gulf? Or does it mean that the Gulf ecosystem is working to break down the oil? Let the debate begin.

But first a quick correction.

Studies of Gulf plankton show a chemical signature of oil. This is not the same as finding oil. It's oil-derived carbon. How did it get into the plankton? It likely happened because bacteria ate the oil and plankton ate the bacteria. Voila.

This does not mean that the plankton are contaminated. Quoting the author of the study:

"What we found was that the system works. It doesn't mean everything is OK and it doesn't mean that there isn't anything out there that isn't toxic. It just explains that the ecosystem is working to process this oil as if it were food."

The oil was treated as "fuel" to grow and reproduce, Graham said. "It's all biomass conversion. If I eat a cow that ate grass, I'm not eating grass; I'm eating what got converted into cow biomass."

Carbon is the element that forms the backbone of all life forms, so the evidence of the oil carbon in the zooplankton doesn't necessarily mean the food chain has become contaminated, Graham explained.

OK, this is a bit tricky. Carbon from oil is making it's way up the food chain. This means the oil has been digested and converted into other forms of carbon--like zooplankton tissue. It doesn't say anything about contamination with actual oil.

Will the world see this as evidence of oil metabolism (the correct view)? Or as evidence that the plankton were dripping in black goo that will poison our seafood (the wrong view)? We'll see, but I'm betting on the incorrect view.

Of course it's good to worry about what our food ate. If we're eating a cow that ate cow brains, we may find ourselves with a brain wasting disease. That would be bad.

So what about this oil-derived carbon in plankton? I don't think seafood with oil-derived carbon is the scariest thing on plates of most people. I'd worry more about mass-produced meat and what those animals have been eating. Give me a Gulf snapper any day.

BTW, I must offer the now-traditional context statement: the oil spill was bad-bad-bad, and I'm not suggesting otherwise. Some animals in the Gulf are contaminated, we know that. And we have to be careful about oil in Gulf seafood. But this carbon from oil story doesn't address that point. This study says that the ecosystem is working to metabolize the oil and that's a good thing.

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