The chief detective is JoAnn Burkholder, a controversial aquatic botanist at North Carolina State University who first identified Pfiesteria in 1991. It is, she says, a vicious microorganism, capable of masquerading as a plant by carrying out photosynthesis, or undergoing at least 24 changes in its life cycle. In waters filled with nutrients, it multiplies tremendously. The organism releases a toxin that essentially drugs the fish and kills them in 15 minutes. ““In a major kill every species has died,’’ says Burkholder. ““Most can’t get out.''
The most intriguing unknown is the organism’s effect on human health. There is no proof yet that it attacks people. But Burkholder says she and her research associate Howard Glasgow have both suffered from exposure to airborne Pfiesteria toxins; their symptoms include dizziness, memory loss, fatigue and asthmatic problems. The symptoms have dissipated, she says, but recur when she exercises, an indication that the toxin may be stored in body fat. ““It’s disconcerting to realize you were an inadvertent guinea pig,’’ Burkholder says. Working with no safety guidelines at first, she has since upgraded safeguards at her lab (in a trailer) to avoid contact with the toxins.
Maryland officials have downplayed the possible human connection, but they’re hedging their bets. The state’s two U.S. senators and the governor immediately asked for federal help, calling in the Centers for Disease Control to investigate. Specialists from Johns Hopkins University are already examining the afflicted men who swam in the Pocomoke River. Environmentalists in North Carolina say the human link is there, too. Says Rick Dove, who monitors the state’s Neuse River for an environmental group, ““I can look at sores on fish and at sores on people, and they are the same sores.’’ About 140 North Carolina physicians agree. They fired off a letter this week to Vice President Al Gore, similar to one they sent earlier this year, complaining that ““the river is sick, the people are sick and we need federal help.''
One of the first tasks for investigators is to figure out what triggers the proliferation of Pfiesteria. The finger-pointing is well underway. In Maryland, environmentalists are blaming the manure runoff from the region’s 600 million chickens. That pollution would raise the level of nutrients like phos- phorus and nitrogen, which overenrich the bay–and allow Pfiesteria to thrive. The poultry industry responds that most of its farms stockpile manure in storage pits. Others have blamed fertilizer runoff.
In North Carolina, environmentalists say the culprit is mostly runoff from hog farms. The pork industry says many sources pollute the waters, and more study is needed. That may be true, but critics contend that the state, protecting its powerful agricultural interests, is moving too slowly to combat a problem discovered six years ago. Indeed, Burkholder’s struggles to get North Carolina to recognize Pfiesteria are legion. A new book, ““And the Waters Turned to Blood,’’ recounts how corporations and state officials attacked Burkholder’s credibility.
North Carolina is finally starting to move more aggressively. Legislators are considering imposing a moratorium on permits for new hog farms, among other measures. The Maryland fish kill should only accelerate the effort to find a solution. For now, as Burkholder puts it, ““this organism is cause for concern, not cause for alarm.’’ ^
dormant for years–until nutrients cause its numbers to soar.
fish, it morphs into forms that emit toxins that eat into the fish’s skin.
with their livers, kidneys and immune and nervous systems wrecked.
