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Q&A: Susan Shaw, marine toxicologist

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Susan Shaw's mission is to save the world's oceans. We spoke to her about her work on the Deepwater Horizon oil spill.

As founder and director of the Marine Environmental Research Institute, Susan Shaw's mission is to save the world's oceans. Recently, her work has focused on the Deepwater Horizon oil spill, beginning a month after the incident when she dove into the slick.

Below are excerpts from our interview last week.

A month after the Deepwater Horizon oil spill, you dove into the oil slick to get a sense of the damage. Tell me about that experience.

About a month after the oil rig exploded, I was asked to go down to the Gulf and investigate what was happening with the dispersant. It was beginning to be applied heavily. In late May [2010], I went out 40 miles from the coast. The oil was floating very thick on the water. On the edge of that, I dove to see what was happening underwater with all the dispersant being sprayed.

What I experienced there was horrifying. Dispersant breaks into the lipid membranes of the oil and produces very small pieces of oil. They get smaller as you go down in the water. As I was underwater, I could see the dispersant breaking up the oil. The hydrocarbons in the oil are released into the water. There was much more hydrocarbon exposure in the dispersed oil mass than in the oil sitting at the surface. Some hydrocarbons are carcinogens. All are toxic to every organ in the body. As I was underwater, I began to see dead things floating around in this cloud of dispersed oil. It did not take long for any marine organism that was exposed to take in oil and die. When dispersant encounters the lipid membrane of a cell or an organ, it goes into that membrane and breaks it down. It therefore takes the oil into the body more readily. Any animal coming in contact with dispersed oil is going to be impacted.

I became rather alarmed being down there. I had complete scuba gear on and all my skin was protected, but my breathing at the surface was an issue. I didn't stay in the oil slick long enough to experience any severe damage. But it was a concern. Other people who dove in the oil had symptoms of taking oil into the body. Usually it starts to affect the nervous system. You can get shakes. You can get severe headaches. You can immediately feel dizzy. Your vision gets blurred.

As I investigated it further, I predicted the animals that would be most affected would be the corals, which are exquisitely sensitive to the mixture of oil and dispersants. Many species are more sensitive to this mixture than to oil alone. Corals are certainly one of those. I also predicted that the mammals that breathe at the surface, the dolphins particularly, would be severely impacted by dispersing the oil. Every time they'd come to the surface to breathe, they would unavoidably take in oil and dispersant in their blow hole. Ultimately, the die off of dolphins started accelerating out of control. It's still going on now. The total number of dolphins that have died from 2010 is over 600. They're still washing up on the shore now 12 at a time.

You mentioned that some other divers were having health problems related to the spill. What is the ongoing human health impact?

The people that came in as response workers were heavily exposed. Many of those people got sick. Also, there are thousands of people who are sick and are involved in lawsuits now in the Gulf. Because I have a public health background, I was put on a federal team to assess the consequences of the spill. It was a group of 14 scientists who did in-depth analysis of what the different consequences would be. My role was to assess human health consequences and consequences to wildlife.

There's no doubt there's a human health crisis [in the Gulf]. Many people who were not sick before the spill -- not just the workers, but also residents -- are severely ill. They're not even able to walk. The exposure was long enough and intense enough to see these chronic health problems in people. I've interviewed people in the Gulf who were affected in the community of Grand Isle. There was a nervous system effect that was common. People had blinding headaches. They went through bottles and bottles of Advil. There was shaking of the muscles. Heart palpitations were common. In some people, 70 percent of the lung capacity was lost. There was kidney damage. People would urinate blood and would have blood coming into their stool, which meant they were bleeding internally. These are all nervous system effects. That's what oil does in the body. I interviewed a 14-year-old girl who went to school on Grand Isle. Right after the spill, she started having headaches. At her school, everyone was having bleeding. They would bleed from the nose or the ears. It was common to see someone go out of the room with ears bleeding. She had vaginal bleeding that never stopped. People who were perfectly healthy before the spill became severely ill.

We advised the agencies that once oil gets in the body, it's a ticking time bomb. You're going to have long-term effects including, very likely, cancer. We predicted chronic human health effects on a massive scale. That certainly did happen. We were told one thing after another meant to minimize what was the largest environmental disaster in our country's history. I've been part of the group looking at this oil spill and it's not a pretty picture.

What are some of the ongoing effects of the oil spill and dispersants in the Gulf ecosystem?

Dispersing takes the oil down, in a dispersed form, to the bottom. We had plumes of dispersed oil floating around in the Gulf. The oil has coated the surface of the bottom of the sea in many areas. They're large patches, hundreds of square miles. Once oil gets into the floor of the sea, it's going to keep recycling and bubbling up. I don't think we're going to know the extent of the damage to the ecosystem for tens and tens of years. We do know that one of the large coral beds that was perfectly healthy in 2009 is dead. You could see miles of dead coral. Not only that, but all the animals that interact with coral are also dead.

We have oil coating the floor. We have dead animals and dead wildlife. There have been dead fish all over the place. Those are mostly the fish at the middle of the food chain. There are tens of thousands of fish dead. I don't think we have an accurate count on anything. When there was high oil exposure, scientists were kept out of the area. We weren't allowed to get samples. Even our health agencies didn't get in until almost the following January. When you go in late, your exposure measure is not a real one. There is widespread damage to that ecosystem. There's going to be ongoing exposure to oil. It's trapped in the sediment at the bottom. When animals are feeding at the bottom, they bring it up into their bodies. They're eaten and everything is moved up the food chain.

What are the lessons coming out of this?

The response to the spill needed to be much improved. We need a better capability to respond to oil spills before moving forward. The lessons are:

  • the response was inadequate
  • the technology on-site was inadequate
  • the drilling technology and back-up plan were not in place

The president appointed a commission to do an in-depth report. The commission delivered a document that resembled a telephone book. They called for more research, better spill response capability and oil spill response plans at each stage of development. The information is on the table now that the containment equipment was inadequate. Less than three percent of the oil from the surface was gathered. When the oil is on the surface, it's in a slick. Once they disperse it, it's gone. It goes down to the bottom and all over the place. We should have containment equipment that represents the 21st century.

None of these recommendations have been followed -- and we're just driving toward more domestic oil. Congress has not passed a single law related to oil spill capacity. There's every reason to think we're going to see another disaster happening sooner than later.

You also study other man-made pollutants in the ocean environment. What worries you most?

For at least 20 years I've been investigating the impacts of toxic chemicals on marine life and human health. I've worked particularly on the sentinel species, marine mammals, because they are the most polluted animals on the Earth. They're at the top of the marine food web. Chemicals [such as pesticides and agricultural and industrial chemicals] we use on land are flowing into the sea. These are persistent compounds.

Recently we've been focusing on chemicals in consumer products, like flame retardants. When a product, like your sofa, breaks down, these chemicals go into house dust. They flow into the waste water when the products are discarded. The ocean is the final place for those compounds. They stay in the ocean food web and recycle for decades. I've been tracking the build up of those chemicals.

What's next for you?

I have also started working on other issues related to the ocean in general. Our oceans are taking it from all sides. It's not just oil or off-shore drilling. I'm also looking into cruise ship pollution. I'm concerned now about plastics getting into the ocean and creating large mountains of debris. My main thrust is in the area of increasing dead zones, plastics building up and cruise ship pollution. We're working with partners to make industries greener. We're going to announce the launch of an ocean toxics project with our global partners. I'm very concerned about the oceans as a whole. It seems to be getting worse.

Watch Shaw's TED talk about the oil spill.

Photo: Shaw with a dead seal that washed up on the rocks in Maine (Seals as Sentinels project)

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Christina Hernandez Sherwood

Contributing Writer

Contributing Writer Christina Hernandez Sherwood has written for the Los Angeles Times, Newsday, the Philadelphia Inquirer, Diverse: Issues in Higher Education and Columbia Journalism Review. She holds degrees from the University of Delaware and Columbia University's Graduate School of Journalism. She is based in New Jersey. Follow her on Twitter. Disclosure