top of page

Academic listening - chemistry


请直接点击以下图片试听音频:

please click the picture below so as to listen to the audio:

Transcript:

0:11I am a marine toxicologist, and I've been very, very concerned about the Gulf, particularly about the massive applications of the toxic dispersants, the Corexits. I've been working on ocean pollution for quite a long time — the impacts on marine life and particularly the impacts on marine mammals. As it turns out, marine mammals are at the top of this food chain that we're pouring millions of tons of toxic substances into every year. And they are showing the signs of this. I'm sorry to have a sad slide like this, but not everything is all that happy, especially in my work. They are loaded with toxic chemicals in their body, hundreds of compounds, all kinds of compounds — it's staggering. And they're dying off rather regularly, tens of thousands around the world. It's predicted they may go extinct — about a third of them — within about 30 years.

1:14So my project is along the Northwest Atlantic. It's called Seals as Sentinels. We're tracking pollution at the top of the food web, in marine mammals and fish. It's a region-wide, eco-toxicological investigation. We're looking at a lot of compounds, but recently been quite interested in the flame retardants, the brominated flame retardants that are in many, many things that we use in our everyday life, from the cushions in the chairs we're all sitting on to the plastic casings of our computers, our television sets and so on. So we are tracking how do these things get from the products into the ocean, which is the final sink for them. And there's quite a complicated pathway for that because, as these products age, they get concentrated in dust, and then they also get thrown out, so they go to the landfills. They wind up in waste water treatment plants. As you all know, we throw out billions of computers and TVs every year. And those go to e-waste dumps. And all that gets into surface waters, eventually reaching the ocean, the final sink. So, in our study, we did find quite high levels, as we expected, of these flame retardants in the harbor seals' bodies. And we reported this. It led to a ban of this neuro-toxic flame retardant called Deca in Maine, where I am based, and also then a phase-out, U.S.-wide, at the end of last year. But we said, well, on the bright side, our harbor seals at least will not be bursting into flame anytime soon.

2:49So then I got really curious, myself, as a toxicologist, and I donated some blood to my lab and said, "Okay, let's do it." Well, we detected 113 different compounds in my blood. And I must say, if any of you would have this done, you'd probably find a similar profile, or cocktail, as they call it. But I was the recipient of a lot of flame retardant material for some reason. And just to point out the levels — Americans have 10 to 40 times higher levels of these compounds in our bodies than the Europeans. Why? Because we are flame-retarding everything, and we have weak regulations for toxic chemicals. But lo and behold, I'm one of the high-end individuals.Lucky me. But then I thought, well, in case of a fire, I might be the last one to ignite.

3:42(Laughter)

3:45So anyway, here's the problem — and it is a problem that we're looking at in the Gulf today —we're not regulating chemicals in this country properly. We're hardly regulating them at all. And we're letting industry run the show. And Jackie Savitz spoke this morning about Big Oil and the propaganda and how we're all brainwashed with their, you know, lies and so forth. Well, Big Chemical is what we're dealing with here. And they're allowed to keep trade secrets, so they don't even give the ingredients out. Plus they don't give health and safety data, so, consequently, they cannot be regulated before they go to market. So it's a case of innocent until proven guilty. The burden of proof is not on the producer.

4:33So I then was invited to go to the Gulf in May. I went down there on a preliminary investigationto look into dispersants and how they're going into the water column and so forth. And I was told that I was the only toxicologist to date who was dumb enough to get into the water, but I did. And we dove in the slick without even HazMat gear. And I did get sick. I got a ferocious sore throat two days later. I felt like my throat was on fire. But it did pass. And what I did see in the water as we went down, what really shocked me — and it's haunted me ever since —because I could see the droplets of oil dispersing. And as you go down, they're catching all kinds of plankton, bumping into, you know, little wisps of life that are the food for the planktivores, the herring kind of fish. And you could just see the web of death as you go down in the water column.

5:36Well, you know, we got into this in the beginning as a trade-off, they say, between the wetlands versus the ocean depth. And I didn't agree with that decision at the time; I still don't. The decision was to protect the marshes. When the oil gets into the marshes, you can't get it out.And as you know, there's been a very weak response, up until recently, to actually collect the oil. It's gotten much more aggressive. This is an Exxon slide showing what happens, the scenario and the trade-off. So this shows oil on the surface. You can see it getting up into the mangrove, but it is not harming the corals or the sea grass, right. So here we have the other scenario. If you disperse, the sea grass and the corals are getting hit pretty hard, but you're saving the mangrove. So this, to me, is like going to the eye doctor, okay? Is it better with one or two?

6:33(Laughter)

6:35The problem is that we have released so darn much of this stuff, we're climbing up to two million gallons very quickly. And then there's the problem of the plumes. What plumes? It turns out there are plumes. Independent researchers found that. And then there's the looming, messy problem of human health, reported human health effects. And actually, one of our federal officials said that it was probably heat stress. So ... Having been in that water just for the short time I was there, I can tell you, it is not heat stress. There are volumes of volatile petroleum fumes coming off that water, plus the Corexit, which has solvent in it. So it is not at all rational.

7:27So what do we have? The BP show is going on. Our officials complained about Corexit, which is the most toxic line of dispersants. But heck, they're still using it, and they used the most toxic one, the 9527, until they ran out of supplies. Now they're on 9500. 9527 had 2-butoxyethanol in it that causes internal bleeding. We know that from the Exxon Valdez spill, by the way. So what we're doing, we're putting compounds with petroleum solvents onto a petroleum spill. Does this make sense? So this is the way it works. And I want to show you this cute little thing that happens here. It's a micelle. Micelles form around the oil. And what happens first is the solvents break into the oil, the lipid membrane, they let the surfactants in there. The surfactants — which are like things we use on fast food wrappers — they grab around the droplets of oil, and they make little, tiny droplets with nice, little surfactant edges to them. The thing to remember about the micelles — these little floating globules of toxin — is they are there to deliver. They're like the FedEx guys. And if you're a fish, and you haven't gotten your glob in the morning, you're going to get it in the afternoon, because they've got your number.

8:54So from a toxicology perspective, this is really awful because Corexit and the dispersed oil are much more toxic together than either alone. And usually the exposure is a combined exposure.The dispersants — as I was saying — their job is to break down the lipid membrane. The solvents in them do that very efficiently. So they break down lipid membranes in our body,starting with cells of the skin, the cells of organs. So it actually hastens oil getting into the bodyeasily and readily. Oil contains hundreds of hydrocarbon compounds and other compoundsthat are toxic to every organ in the body. And so with the dispersants combined, you have this very synergistic combined toxicity. Corexit also contains petroleum solvents and many other toxic compounds. And I'm part of a chat group, which is a national group of toxicologists and chemists that are, you know, basically turning cartwheels trying to figure out what's in this stuff,and what is it doing and what are the interactions of these chemicals, most of which we don't know, and what are their byproducts, which are usually more toxic than the parent compound.So we did find that Corexit 9500 contains heavy metals, arsenic and chromium — arsenic at high enough levels to have cancer-causing effects.

10:29So this is what we have to look at, these, you know, ridiculous safety data sheets, which have nothing on them much. And now they were forced to release the ultimate list of everything that's in Corexit. And guess what, tons of stuff is missing. Derivatives, derivatives, these are whole big groups of many, many compounds, these sorbitans. And then you get down to the petroleum distillates, which are the solvents, hundreds of them. They are not identified. And why? Trade secrets again. BP's running the show, and the Nalco company, this is all they have to do. So far these ingredients have not been released, and toxicologists are actually going nutsbecause we cannot predict with certainty what the interactions and toxic results are going to be.

11:23But we do have quite a lot at risk down there, as we all know, the 33 wildlife refuges, so much wildlife and fish and diversity. So we know from previous spills. And then part of this is just part of my bad dreams. And I appreciate being able to vent some of my anguish upon you. What we do know is that the corals are going to get hit hard. And this is a study that was done on the Australian coast, the coast of Tasmania. Corals are, you know, the home to about a quarter of all marine species. And with the Corexit and the oil, there's zero percent fertilization. With oil alone, there's 98 percent fertilization. So they're a very sensitive species to this combo.

12:16Here's another group. I could see myself easily in the water column. The plankton and the plankton eaters, you know, these are the little herring fish that go through the water column with their mouths open, feeding indiscriminately and just lapping up this brown pudding of toxic stuff. And we do know from other studies that this is a highly toxic mixture. See the oil and Corexit is causing death at a much, much lower dose than oil alone. That's probably as far as what we do know about toxic effects. But my bad dreams go like this. The piscivorous fish, the cobia, grouper, amberjacks, those big fish, also the tuna and sharks, are going to hit by this.And the gills are quite sensitive. The respiratory system is very sensitive. Think about it with the Corexit hitting the membranes, and it will clog up the gills, and then these animals are going to be getting something like what you call chemical pneumonia, trying to aspirate the compounds.It also will cause internal bleeding upon ingestion. I'm very worried about the air-breathing mammals because I study them, but also, the way their going to be exposed is every time they come to the surface to take a breath, they're going to inhale these volatile fumes. And what does happen with that eventually is pneumonia sets in and liver, kidney, brain damage. The Corexit is transporting the oil into every membrane and every system of the body. And you're having a lot of different unpleasant effects, but burns to the eyes and mouth, skin ulcers, lesions. And I think, personally, that we have not begun to see the impacts of this spill on the wildlife of the Gulf.

14:13We started hypothesizing: what do we know? what do with think would be a trophic cascade?which means that somebody gets wiped out, and then everything above that's eating those guys will crash. So our thought was — this is a simple thinking process, but ... obviously the plankton, the planktivores, and that's about as far as we got. And then it turns out we're not very good at figuring this stuff out. This is what the Exxon Valdez scientists thought would happen, this trophic cascade where you lose the kelp and the herring and other fishes and going up. They thought that eventually the killer whale would be at the top of this cascade. And then here's what really happened, much more complicated, much more specific. Actually the kelp and the barnacles that attach to the rock were decimated by the combination of Corexit and the oil. They were replaced by invasive species, which had less holding power to the rock.Storms came along. They ripped out of the rock. And this was the entire food web for the sea ducks. And as you know, we lost about 300,000 sea ducks from the Exxon Valdez spill, and they haven't come back.

15:28So we are launching an independent study. And by independent, I do not mean alone; I mean independent in the sense of not tied to the kind of crime-scene secrecy that's going on in the Gulf now. But we are actually going to be assessing toxic impacts, but we need lots and lots of partners to do this intelligently. We have some of the partners lined up. And Dave Gallo signed on. Sylvia's in here. And we hope that some of you will help us. My question to you is: why shouldn't we know? Don't we have the right to know? Surely we have the right to learn what loss we are going through in the Gulf. And my wish would be — for the gulf prize — would bethat we have the truth. Whatever it is, please let us have the truth. And to get there, we need to do the assessment.

16:27So I appreciate being here. Thank you.

16:29(Applause)

bottom of page