J. Leichter, Scripps Institution of Oceanography/UC San Diego

North Pacific Ocean Gyre collections from August 10, 2009 revealed small velella jellyfish, each about the size of a quarter, with lots of plastic.J. Leichter, Scripps Institution of Oceanography/UC San Diego

The Scoop: Last summer, Miriam Goldstein of Scripps Institution of Oceanography led a research cruise to the North Pacific Gyre to see for herself how much plastic there was and whether it was making its way into the food chain. What she found surprised even her, and left more questions than answers about how our society's obsession with plastic is impacting the oceans.

Reilly: So, let's start with a little background info; what is SEAPLEX and how did it come about?

Miriam Goldstein: SEAPLEX is the Scripps Environmental Accumulation of Plastic EXpedition. It came about after 6 Scripps graduate students heard a talk by Marcus Eriksen, who was then with the Algalita Marine Research Foundation.

Miriam Goldstein: Algalita was founded by Charles Moore, who discovered the trash in the North Pacific in 1999.

The students were inspired by Eriksen's talk, and since there was relatively little scientiifc knowledge about this issue, we decided to try to go out and see for ourselves.

We wrote a grant and entered in a yearly competition called the UC Ship Funds, which allows students to design & run their own cruise -- this is pretty unusual!

We won, and off we went to the North Pacific Gyre last August.

SEE PHOTOS of the Great Atlantic Garbage Patch.

Reilly: Wow, so the University of California handed you the keys to a scientific research ship, and said "have fun." Not shabby.

Reilly: So, what is the gyre exactly? And why is it a trash magnet?

Miriam Goldstein:The gyre is a natural formation of ocean currents driven by the trade winds. The jet stream/westerlies in the north push the water east, and the trade winds in the south push the water west. As the earth turns, all that water moves in a clockwise motion.

The center of this big circle is the North Pacific Gyre. It's a calm, warm area with relatively sparse life, compared to the coasts.

It's a trash magnet because of that current structure. Anything that falls off the west coast of North American & the east coast of Asia will end up there, provided it doesn't sink or biodegrade. It's a one-way trip.

Reilly: Right -- I've heard it called a "biological desert."

Miriam Goldstein: Yes - there are cool, specialized animals that can make a living out there, but there are relatively few of them. It's not, for example, where most of the fish we eat come from.

Reilly: Gotcha. But one of the concerns is that marine life is interacting with the trash, right?

Miriam Goldstein: That's right. There's definitely interaction with albatross, for example.

And the open ocean is incredibly important to global cycles - about half of our oxygen is made by tiny plants in the ocean. Since the North Pacific Gyre covers a vast area, it's a big concern if it's impacted by plastic trash.

In SEAPLEX, we focused on the small animals at the bottom of the food chain, such as bacteria, phytoplankton (microscopic plants), zooplankton (microscopic animals), and small fishes.

WATCH VIDEO: What's an ocean garbage patch, exactly? Find out.

Reilly: That makes sense -- because there are so many of them, they are really important. And the big fish we eat (salmon, tuna, and so on) eat the little guys. So in effect, we're eating whatever the small fish eat?

Miriam Goldstein: That's right. One type of fish that we looked at, lanternfish (scientific name: myctophids) are the most common fish in the ocean. They're very important prey for tons of bigger animals, like tuna and squid.

Of course, we're not eating fish guts, so we wouldn't be eating plastic bits directly. But one of the concerns is that plastic can transfer toxins into the fish's body.

There have been studies showing that plastic particles accumulative high levels of toxins such as PCBs and DDT. There has been one laboratory study, done with birds, that found that birds that ate these particles did have higher levels of toxins in their bodies than birds that did not.

Reilly: Right. So that's kind of scary -- the idea that by tossing trash in the oceans, we're in effect poisoning not only animals, but ourselves.

Do we know whether or not this is happening, and to what degree?

Miriam Goldstein: Oh, we're certainly poisoning ourselves! One huge concern in seafood is mercury, which is not related to plastic but to fossil fuel emissions. Top predators in the ocean (tuna, swordfish, sharks, etc.) have incredibly high levels of mercury in their bodies and this is transferred to us when we eat them.

These predators also can have high levels of PCBs and DDTs, but those chemicals are in the environment and are not necessarily related to plastic.

The role of plastic particles in transferring toxins to seafood is currently not known.

Reilly: Jeez, that's an uplifting picture.

Miriam Goldstein: It is really sad. But the good news is that by eating less of these top predators and by advocating for sustainable fisheries, we can help both ourselves and the ocean.

So it's way more environmental bang for the buck!

Reilly: So, to be blunt about it, why care about the plastic story? It's sure gross to look at, but unless it's a major player in the toxics question, shouldn't we focus on cleaning up PCBs, mercury, and other pollutants directly?

Miriam Goldstein: Well, to answer your second question first, there's no way that I'm aware of to clean up those other pollutants directly. PCBs have been banned for around 30 years in the US and they're still around. But we can definitely cut down on the mercury by advocating for clean energy.

But to get back to the plastic, I think we should care because most of Earth is the ocean, and most of the ocean is in these vast subtropical gyres (there are actually 5, of which the North Pacific is one).

If plastic is damaging them, that is affecting everything from oxygen generation to carbon removal. We need healthy oceans to be healthy, even if we're not eating the animals that live there directly.

Also, it's incredibly depressing to go out to one of the most isolated places on earth and find that it is littered like a fairground after the 4th of July. I think people need to know that there is untouched wilderness out there - we need there to be wild places to discover. And what is more wild than the ocean 1000 miles away from any land?

We've explored less than 5 percent of the ocean, so there are so many exciting things to be discovered!

Reilly: My understanding is that these gyres are really just places where plastics tend to concentrate, because of the climate conditions you mentioned. But this idea of a "garbage patch" is kind of misguided -- that in fact all of our oceans have become in effect a thin soup of plastic.

Miriam Goldstein: Yes, when people look for plastic trash in the ocean, they tend to find it. We sampled 126 swimming-pool-sized areas of the surface, and found plastic in every single one. There was more in the North Pacific Gyre, but we also found some off California and Oregon.

Reilly: It must be a weird contrast to be out there in what looks like endless blue ocean, and then drag a net through the water and find all of this garbage.

Miriam Goldstein: It was REALLY surprising to all of us. We expected to find some, but we did not expect to find it in every single tow.

Also, since more than 90 percent of the plastic bit are less than the size of a pencil eraser, they cannot be seen just with the eye (or from satellite or Google Earth). To get them you have to put a fine-meshed net in the water.

I would look at the net as we were towing it and know that the plastic particles were going in, but I still couldn't see them. Or, rather, I could see a few but not the hundreds or thousands that would come up in the net.

Reilly: You say 90 percent of the particles you found were tiny. Do we have any idea how fast we are dumping plastic into the ocean, or how fast the garbage "patch" is growing?

Miriam Goldstein: Unfortunately not. Currently there is no way to tell if a certain particle has been in the ocean for 3 years or 30 years. This is something that we're working on but we don't know how to do it yet.

Reilly: Since you returned from the high seas last summer, what have you been able to learn in the lab?

Miriam Goldstein: We're still working away. Time at sea is so valuable that what we do is take as many samples as we possibly can and then work on them back at the lab. So that makes for a LOT of lab work!

But I can definitely tell you that we found plastic in every single surface sample for over 3000 miles.

Reilly: Wow. How about fish? Are they eating this stuff?

Miriam Goldstein: Yes, the fish researchers, Pete Davison and Rebecca Asch, have found some fish that ate plastic particles. The most interesting find was a deep sea hatchetfish which had eaten the particle around 900 feet below the surface. Reilly: Have you seen any of the toxins you mentioned in their tissues? Miriam Goldstein: We don't know about the toxins yet - that work is still ongoing. Reilly: Okay, I know you've got to go, so last question: This stuff is so pervasive, and we aren't doing much to stop more from constantly flowing into the oceans. So how do we fix the problem? Is it fixable? Miriam Goldstein: The best way is definitely to stop it from going into the ocean in the first place. And there are known ways to do that -- for example, putting trash collection devices on rivers and creeks before they flow into the ocean. But once the trash is in the ocean and it breaks down into these little pieces, it's pretty hard to get it out again. It's the same size as the zooplankton (tiny animals, essentially fish food) and it's everywhere. Project Kaisei, a nonprofit that partially funded SEAPLEX, is working on possible solutions. Reilly: Well, it's been a pleasure talking to you, Miriam. Thanks for taking the time to chat. Miriam Goldstein: Thanks so much! I enjoyed talking with you as well. Get the whole story on plastic in our oceans -- and in ocean mammals -- in this Wide Angle: Drowning in Plastic.