She calls it the career from hell-and she鈥檚 only half joking. She鈥檚 been hounded by powerful industries, seen her lab closed and watched her funding disappear. What did algal biologist JoAnn Burkholder have to do to achieve this distinction? Not much, says Burkholder, who works at North Carolina State University-just tell the truth about a creature that changes shape and size with no warning. Worse than that, it comes armed with a nerve poison that attacks fish and researchers alike. Stephanie Pain listens to her story.
Tell me about Pfiesteria piscicida-the thing they call the cell from hell. What exactly is it?
Pfiesteria is a member of a very ancient group of single-celled organisms called dinoflagellates. They are a wonderful group of organisms, half of them are plant-like and half are animal-like. Pfiesteria is one of the animal-like species.
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So why do people call it the cell from hell?
I think the biology of this organism has captured people鈥檚 imaginations so they give it almost human attributes. Many dinoflagellates produce harmful toxins but Pfiesteria is also what is known as an 鈥渁mbush predator鈥� and attacks fish. It has a fascinating life cycle in which it transforms into 24 different shapes and forms. It can change size from 5 micrometres to 750 micrometres-an enormous difference for a microbe. Some forms look like green algae because they鈥檝e 鈥渂orrowed鈥� or stolen chloroplasts from algae they鈥檝e eaten. Others are blob-like amoebas. Sometimes the whole population 鈥渄isappears鈥�, sinking out of sight at the bottom of the estuary, and then swims up and attacks fish. After killing them, Pfiesteria cells transform into large, colourless amoebas, attach to the carcasses and feed on the remains. Unless you watched the transformations, you鈥檇 never realise it was the same creature.
What makes it attack fish?
Pfiesteria can eat almost anything, from bacteria to mammalian tissue. Most of the time it鈥檚 harmless. It only makes toxins if there are live fish around, under conditions where it can detect them. If you鈥檙e a fish just moving through, you鈥檙e OK. But when large schools of fish linger to feed in quiet brackish waters, enough of their secretions and excretions build up for Pfiesteria to detect them. Then they start making toxins.
How does Pfiesteria kill fish?
One of the first effects is to 鈥渄rug鈥� them. They become lethargic and then suddenly behave as though they are trying to shake themselves out of it, or they come to the surface and gulp air. And from there, the toxins begin to affect the nervous system. We believe that the fish die from suffocation. Some components of the toxin also dissolve the fish skin and create gaping, bleeding holes.
How big a problem is it?
I think Pfiesteria is established worldwide but it鈥檚 usually benign. It takes a special set of circumstances before it causes problems. It鈥檚 no accident that the estuaries of North Carolina are the epicentre of toxic outbreaks. They are warm, quiet, shallow and poorly flushed. And they are highly enriched with nutrients because we have huge swine and poultry industries and a burgeoning human population, so there are lots of untreated and poorly treated wastes going into the water.
How many fish does Pfiesteria kill each year?
The fish kills have been worst by far in North Carolina. The 鈥渂est鈥� year Pfiesteria has had was 1991-more than a billion fish died. They were bulldozed from beaches. Since then, in some years hundreds of thousands to millions of fish have died.
You too were attacked by Pfiesteria鈥�
After we linked Pfiesteria to the fish kills in the estuary, we asked people who worked on other toxic dinoflagellates what precautions we should take when working with this organism. We were told to wear a lab coat and gloves. We didn鈥檛 realise that the cultures that were killing fish in our tanks were also apparently emitting neurotoxic aerosols into the air. Of the 12 people exposed in laboratories, five were seriously affected, including two in my lab. All five suffered severe but fortunately short-term memory loss. While we were affected we couldn鈥檛 hold a conversation. We could recognise words but we couldn鈥檛 put them into sentences. We could add 1 plus 1 but we couldn鈥檛 manage 3 plus 4. I was the first affected that way in my lab.
So what happened to you?
I lost eight days of my life. It鈥檚 like the tape was erased except for just a couple of clear visual memories. I had been sampling one of the toxic tanks. I remember that my gloves were dripping with water and watching my hand come up in slow motion to my face so that I could rub my eyes. I had lost the ability to realise that something was seriously wrong. My eyes were burning badly yet I was rubbing toxin-laden water into them-something I would never do if I hadn鈥檛 been affected by this toxin. I don鈥檛 remember being helped to an elevator but I鈥檝e been told that I was, that I doubled over, had severe stomach pains, muscle cramping and asthma-like symptoms when the drugging effect wore off.
Did you know what was happening to you? Were you scared?
I guess what I experienced might be something like what happens to people in the early stages of Alzheimer鈥檚 disease-there are clear moments when the person realises something is very wrong but then sinks back down. During those lucid periods it was very frightening. I knew I had lost the ability to think clearly. I had once had a photographic memory and suddenly I couldn鈥檛 even remember two digits of a telephone number.
What did you do?
I hid in my apartment. During lucid moments I would test myself. I鈥檇 try to write down what a TV news commentator said, even a four-word sentence. It was only when I was finally able to remember a short sentence that I began to hope I would come out of it.
How did people react when you told them?
People didn鈥檛 believe it. When I went back to work, some of the university professors told me I shouldn鈥檛 say anything-if I asked too many questions my research would be shut down. Others said that I must be making it up. Most university safety officials didn鈥檛 seem to believe it either, but I think they were concerned about the potential for liability. We were moved into a small trailer that was supposed to have been designed to prevent further exposure to toxic aerosols.
So then everything was fine?
No, not at all. It turned out that toxic aerosols were vented into working areas that were not even near the toxic cultures. Air that was supposed to be ventilated to the outside was shunted directly over my research associate鈥檚 desk. A few months after we moved there, he spent a particularly intense day working long hours-and suddenly collapsed. He couldn鈥檛 remember his name. He couldn鈥檛 find his way home, and his reading ability degenerated to the level of a seven-year-old. He鈥檚 a highly intelligent man but he had to take reading lessons and it took three months for him to recover his learning and reading abilities. He suffered from other health problems as well, and still has bouts of illness after seven years.
Does anyone know how long the effects last?
No. I鈥檝e been told that three of the five people badly hurt have had sporadic but serious multiple-sclerosis-like symptoms. My research associate still relapses and I appear to have symptoms of immune system suppression. I鈥檝e had 16 episodes of pneumonia-something I鈥檇 never had before-and I鈥檓 on antibiotics 200 days a year. I鈥檓 hoping that will begin to reverse but we really don鈥檛 have any idea of what the long-term effects of these toxins will be.
After these injuries, did people take more notice?
No, at least not in a positive way. Instead, we encountered enormous resistance-from environment and health officials, various industries such as the swine, seafood and tourism industries, and from coastal developers. There was major resistance to most aspects of the research. The link to fish kills and especially the effects on people were seen as a threat to the local economy. Funding from most local sources suddenly dried up.
Did fishermen ever have health problems?
They were, and still are, reluctant to talk because there was a great deal of pressure on them to keep quiet. But early on we began to hear some very disconcerting things in quiet conversation. One fisherman told me: 鈥淚 know these estuaries like the back of my hand and I got lost-I had no idea where I was.鈥� There were places fishermen wouldn鈥檛 go. They called these places dead zones. Some of them described suddenly passing out and vomiting on the boats. They talked about disorientation and memory loss. It made me very uneasy because it sounded so similar to what had happened to us. And although they didn鈥檛 know it, the areas they were describing were places where toxic Pfiesteria had been active.
So why do you still work with Pfiesteria?
It鈥檚 really not the cell from hell-I don鈥檛 think that鈥檚 a fair way to describe Pfiesteria. It鈥檚 more like the career from hell. I don鈥檛 mean that seriously, but when we first began to encounter extreme opposition we knew things were going to be difficult. But we believed that people were getting hurt from Pfiesteria and we just didn鈥檛 think we could turn our backs on that. Also, we really want to know about these toxins and how they affect people, because of our health problems and because other people had been hurt.
What did it take to make people take Pfiesteria seriously?
Three small outbreaks of toxic Pfiesteria in Washington DC鈥檚 backyard. In 1997, about 30 000 fish died during those outbreaks in Chesapeake Bay in Maryland. More than a million fish died during outbreaks in North Carolina that year, but Maryland is close to Washington DC and the press coverage was enormous. Also, while North Carolina had tried for years to deny there was a problem, in Maryland action was swift. The governor called out the National Guard to make sure no one went near those waters until the outbreaks were over. And he immediately asked for medical tests on about 15 people who had been exposed to the toxins. Some of them were diagnosed in the bottom 2 per cent of the US population in their ability to learn and remember. Suddenly, Congress was talking about it.
What did that mean for you?
Suddenly we had recognition from another state. North Carolina was, I think, embarrassed and the state legislature provided generous funding for a new biohazard level 3 lab. With that we are now making good progress in characterising the toxin, and we are doing experiments to examine the effects of human, poultry and swine wastes on Pfiesteria. People are now aware that water quality, fish kills and human health go hand in hand and that we need to do much more to protect our rivers and estuaries.
Has the opposition to your work died down now?
No, it鈥檚 still pretty vicious from some quarters, especially from the seafood, swine and poultry industries. The swine and poultry industries closely track my activities and continually put out misinformation to try to discredit our research. That鈥檚 to be expected, I suppose, but one of the more shocking things I鈥檝e encountered has been the deplorable ethics of some scientists. Some government agencies given a lot of money for Pfiesteria research have improved our understanding of Pfiesteria but others simply absorbed it or spent it on other issues. Far worse has been the conduct of certain scientists-for-hire who have been willing to help the various attempts to discredit us. There are many scientists with integrity but it only takes a few of the others to create confusion over an issue and block progress. Frankly, I find Pfiesteria鈥檚 behaviour more refreshing than that of some of the scoundrels I鈥檝e encountered in industry, on the political scene and in the scientific community. At least say that Pfiesteria has a certain purity of purpose and clearly demonstrates its intentions. To me, it鈥檚 still a fascinating creature.
