Pollutants turn a lowly amoeba into a killer
HOVERING OVER A 10-GALLON aquarium containing millions of the microscopic organisms she had found concentrated in North Carolina’s rivers, Dr. JoAnn Burkholder felt her eyes beginning to burn. Without thinking, she rubbed them with a gloved hand still wet with aquarium water. Almost immediately she felt unsteady Her movements and thinking slowed. An hour or so later her stomach began to cramp and she had trouble breathing. Then, for the next eight days, holed up in her apartment and afraid to report to her job as a botany professor at North Carolina State University, Burkholder felt as if her brain had stopped working. “I remember staring at the words on my computer,” she says, “but I couldn’t put them into sentences. I couldn’t even remember my phone number.”
The attack, in January 1993, provided Burkholder, now 43, with the best evidence yet that Carolina waterways were harboring a dangerous microbe. For three years she had been studying Pfiesteria Piscicida, a member of a 450-million-year-old family of one-celled organisms that thrive in the warm, brackish waters of tidal estuaries and cause huge, red-tide-type fish kills. “The toxin that Pfiesteria produces can go right through membranes, ripping and dissolving fish skin,” she says. Now she realizes that it could do terrifying damage to people who live and work near microbe-infested waters or eat diseased fish.
Burkholder’s finding was not welcomed by North Carolina state officials. According to her they feared that if she could prove that urban runoff and wastes spewed into rivers from pig and poultry farms were creating conditions hospitable to Pfiesteria, it would have a negative impact on tourism and industrial growth. Even as Burkholder battled the effects of her own infection—including eight bouts of pneumonia and a weakened immune system—she found herself at war with government agents responsible for protecting people from such hazards.
Her previous warnings about Pfiesteria in 1991 had been met with “organized indifference,” says Burkholder. “State environmental officials acted as if the organism didn’t exist.” When she persisted, health and environmental agency workers began attacking her professional and personal reputation, she says. “They went so far as to say I was sleeping with my students.” Even after her illness, at a March 1994 meeting of advisers appointed by North Carolina Gov. James Hunt, the director of the state’s water quality program scrawled “bulls-t” across recommendations Burkholder had cowritten urging that the state restrict land use. A year later, she says, she received two anonymous telephone death threats.
But Burkholder hasn’t backed down. “People are getting hurt,” she says. Less than a year after her own exposure to Pfiesteria, in fact, her research assistant Howard Glasgow was disabled by the organism. For eight weeks he suffered from oozing skin sores, excruciating headaches and a “mental fogginess” that lingered for months. “I had to learn how to read all over again,” he says. And more than 100 fishermen who had apparently breathed in the toxin while working in Pfiesteria-infested waters have reported symptoms—disorientation, memory loss and skin infections—that Burkholder says are the hallmark of Pfiesteria exposure.
In March, with the publication of And the Waters Turned to Blood, a book on Burkholder’s work, information about the Pfiesteria hazard finally began reaching a wider audience. Author Rodney Barker says he first stumbled on the topic in October 1995, when he saw an enormous fish kill in North Carolina’s Neuse River during a fishing trip. Research led him to Burkholder, he says, and then to the discovery that North Carolina bureaucrats had indeed turned their backs on a major public-health threat. Though officials continue to deny they have been lax—”We have no solid evidence that Pfiesteria can be harmful,” says State Health Director Dr. Ron Levine—Burkholder recently received a state research grant of $250,000 to identify the toxin that Pfiesteria produces and find ways to control the microbe’s growth.
The younger daughter of Marcus Burkholder, a retired foundryman, and his wife, Ethelle, a homemaker, Burkholder came by her love of nature while growing up in Rockford, Ill. Taken on wilderness outings by her part-Cherokee father, she learned to track animals in the snow and to identify birds from lost feathers. “By the age of 5,” she says, “I knew I wanted to be a scientist.” She also learned the importance of not backing down. Her father, who had been raised for a time in an orphanage, would tell her stories about his being bullied by older kids. He always fought back, even when he knew he would lose, “because people would think twice before coming after him again,” she says.
After earning an undergraduate degree from Iowa State, Burkholder got a Ph.D. in the water sciences from Michigan State. She was introduced to Pfiesteria in 1989, when a colleague at North Carolina State, where she had been teaching for two years, asked her to help him figure out what was killing the fish he was studying. First she isolated the microbe responsible, then viewed it under a microscope. “I was spellbound,” she says. “It had 24 different stages in its life cycle, and I could watch it suddenly enlarge in size and, within minutes, be a totally different shape. If you put a drop of blood on a microscope slide, you could watch it being devoured. I had never known of anything like it.”
Scientists had thought the different stages represented discrete organisms; Burkholder was the first to show that Pfiesteria is a single-cell creature that morphs into different shapes depending on its diet. Her success as a researcher, says Dr. Jane Lubchenco, past president of the American Association for the Advancement of Science, is due to her “openness to what the natural world is telling her about how it works.” Sometimes, Burkholder realizes, the message is partly: “Be careful.” Today her lab is equipped with a complex air-filtration system, and she wears protective clothing and a respirator when working with the organism that once laid her low.
Deeply involved in her work, Burkholder permits herself just two distractions: Peanut, her sheltie, who had been abused by a previous owner, and her boyfriend Mike Mallin, 44, an aquatic ecologist at the University of North Carolina at Wilmington. “JoAnn has a heart for people or animals picked on by larger forces,” he says.
Now that one of those forces, the state bureaucracy, has reluctantly come around, Burkholder can focus on this fish-killing microbe. “All I ever asked was that Pfiesteria be treated as a problem that needs to be seriously addressed,” she says. “Now we’re scrambling to find out how toxic the microbe really is.”