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Living On Earth

 

http://www.loe.org/shows/shows.htm?programID=97-P13-00038#feature1

 

 

Then by a mechanism not clearly understood, the cell transforms into a

toxic state, including one that looks under a microscope like the

scrunched up face of an angry baby. At this point the microbe has

grown a tail to propel itself and a suction cup appendage called a

pedunkle to attach and feed on its prey.

 

 

 

 

Pfiesteria: Cell from Hell

 

 

 

CURWOOD: This is Living on Earth. I'm Steve Curwood.

An unusual single-celled organism that seems to flourish in polluted

waters is being blamed for massive fish kills in Maryland, Delaware,

Virginia, and North Carolina. The disease agent is called pfisteria

and scientists have dubbed it the cell from Hell. And now, some

researchers, anglers, and divers suspect it may also harm humans. The

pfisteria outbreak has become so widespread that no less than 4

various government bodies are looking into its causes and ways to

control it. Reporter Diane Toomey begins her story near the site of

one of the earliest reported pfisteria outbreaks, on North Carolina's

Neuse River.

 

TOOMEY: There was a time when Margaret Jones saw the Neuse River as a

giver of life. For years her husband David fished the lower reaches of

the river, and ran a small neighborhood seafood market on North

Carolina's eastern shore. But the store's been closed for 2 years.

Margaret Jones reads the sign that hangs outside it.

 

JONES: It says, " We told the truth. Therefore, we were put out of

business. I'm disappointed and sad. Thanks, Dave. "

 

TOOMEY: In the autumn of 1995, pfisteria hit the lower Neuse. It

marked 15 million fish with open, bleeding sores, and killed them. So

Mr. Jones wondered if the fish he was selling were safe to eat. No one

could give him a straight answer, so he put up a sign that read, " Eat

at your own risk. " His business soon failed. Now Mrs. Jones believes

the same thing that killed the fish infected her husband. He hasn't

been able to hold down a job and has trouble holding conversations.

Sitting at the water's edge, she says her husband suffers from a

number of symptoms.

 

JONES: You could still see where he had the sores on his body. His

neurological system is really bad. He still has a lot of memory loss.

His weight is real bad; he's lost a lot of weight. He can't handle

situations. He doesn't like to be around people. It makes him terribly

nervous.

 

TOOMEY: It's not clear what sickened Mr. Jones. There is no lab test

that can show if pfisteria has invaded his body. But a neurologist has

ruled out other possibilities like Alzheimer's and Muscular Dystrophy.

Other fishermen and divers who work for the state say they, too, have

been sickened by the water. They complain of skin lesions, shortness

of breath, and memory loss. Whether pfisteria is responsible for these

illnesses is a controversial question. North Carolina officials have

warned people to avoid the water and fish where kill is taking place,

but discount the possibility that people who swim or boat on the water

could be poisoned by the organism. Dr. Stanley Music is North

Carolina's top environmental epidemiologist.

 

MUSIC: We had some physicians who were asking questions, and we

followed through with those, and we found alternative explanations. We

had people who complained. We conducted meetings in coastal counties.

There were public announcements and requests for people to report. All

of these things were followed up on, and nothing came of it.

 

TOOMEY: But that wasn't the case in Maryland. After a recent fish kill

on the Pokomoke River, Maryland quickly assembled a team of doctors to

examine more than a dozen sick people there. They concluded pfisteria

is the most likely cause of the troubles, which for some patients

included impaired brain function. As a result, 2 Congressional

hearings, a conference of 5 governors, and a workshop at the Centers

for Disease Control have all been scheduled on pfisteria. Just days

after Maryland physicians announced their findings, North Carolina's

health department decided to set up its own team of doctors to

evaluate possible pfisteria cases. Cases that critics say have been

under North Carolina's nose for years. Dr. Music says the Maryland

study is impressive, but he says much more research is needed.

 

MUSIC: It's just in this one place, in Pokomoke City, where for

reasons that we do not understand there is an apparent cluster of

cases. But even that needs much further definition before we are

satisfied that we understand what it all means.

 

TOOMEY: That more exact definition may soon be on the horizon in the

form of a diagnostic test.

 

BURKHOLDER: We have been able to isolate and purify biologically

active, physiologically unique, water-soluble neurotoxin from pfisteria.

 

TOOMEY: Joanne Burkholder is an aquatic botanist at North Carolina

State University. She identified the unusual organism in the lab in

1988, and at the site of a fish kill a few years later. But pfisteria

has been an elusive quarry. Part animal, part plant, a shape-shifter

with 100 forms and 24 life stages to call upon. Unlike any other of

its kind, it hunts, shooting out a poison that never fails to kill its

target.

 

(Voices milling)

 

TOOMEY: Speaking at an August conference of marine scientists, Dr.

Burkholder said corralling the toxin was a real breakthrough.

 

BURKHOLDER: That is going to really open the door to help us to

understand a lot more about how and where people are being affected.

What tissues the toxin would go into, how it actually works inside of

a person to cause some of the symptoms we have sustained.

 

TOOMEY: Dr. Burkholder says 4 years ago she and a number of colleagues

were poisoned by pfisteria fumes in her lab. They suffered from

nausea, mood swings, and memory loss, with some symptoms persisting to

this day.

 

(Buzzing; boat motor)

 

TOOMEY: So where are we headed, Rick?

 

DOVE: We're heading down the river toward the mouth of the river.

We're going to one of the hottest areas for fish kills in the Neuse

river, which happens to be about right in front of my house.

 

(Music up and under)

 

TOOMEY: Rick Dove likes to say his job is to give a voice to this

waterway. He is the river keeper, hired by the Neuse River Foundation

to monitor conditions here. Mr. Dove is at east on the water, but his

straight back hints at his former career as a Marine Corps colonel.

These days his business card pictures a dead fish.

 

DOVE: In this whole area here, we would go from one side of the river

to the other and all you would do was just count dead fish floating

everywhere.

 

TOOMEY: That was in the pfisteria outbreak a couple of years ago that

killed 15 million menhaden. In 1991 one billion fish died. This year

in North Carolina, pfisteria has killed about a million fish in the

Neuse and Pamlico estuaries. And the height of the fish kill season is

still ahead.

 

(Chains being drawn on wood?)

 

TOOMEY: Rick Dove stands on his dock and throws a cast net into the water.

 

(Splashing sounds)

 

DOVE: Let's see what we've got, if there's any sores on them. Now look

at this one right here, it's exactly what I'm talking about. See this

size, this is about half the size of a dime. It's going to get much

bigger, but you see how it's a round open ulcerated bleeding sore, the

red, you can see the flesh and everything. Pfisteria has done that to

this fish. This fish will not live.

 

TOOMEY: Pfisteria belongs to the order of life called dinoflagellates.

Some of these take the form of algae and some cause the toxic blooms

known as red tides. Pfisteria has been found in waters from Delaware

to the Gulf of Mexico. And for much of the year it lies dormant as a

cyst in the river's sediment. Then by a mechanism not clearly

understood, the cell transforms into a toxic state, including one that

looks under a microscope like the scrunched up face of an angry baby.

At this point the microbe has grown a tail to propel itself and a

suction cup appendage called a pedunkle to attach and feed on its prey.

 

BURKHOLDER: Here's live pfisteria. It's kind of dancing about, it's

been consuming human blood cells.

 

TOOMEY: Dr. Burkholder peers into a microscope at a pfisteria cell in

one of its many guises. It takes intense training to be able to

identify all the stages of the organism. Burkholder is one of the few

people who can do it, so she's compiling an album of mug shots to help

other scientists identify pfisteria. She says the organism naturally

thrives in brackish estuaries where fresh and ocean waters mingle. But

pfisteria may have other preferences as well.

 

BURKHOLDER: About 75% of our fish kills have occurred, that we've

implicated pfisteria in at least, have occurred in degraded waters,

where there is nutrient over-enrichment. Both nitrogen and phosphorus

tend to be involved.

 

TOOMEY: In other words, in rivers like the Neuse, which are overfed.

There, excess nitrogen has spurred algae growth, which in turn has

robbed the river of oxygen.

 

BURKHOLDER: We poured millions and millions of tons of fertilizers,

human sewage, swine waste, poultry waste, all kinds of different forms

of nitrogen and phosphorus and other organic wastes that pfisteria

likes into these estuaries for the past 50 to 70 years, and I think

slowly over time we slowly shifted the balance more in favor of this

organism to become toxic.

 

TOOMEY: Embarrassed by enormous fish kills and hog waste spills, North

Carolina has taken some anti-pollution actions. The state legislature

has just passed a 2-year moratorium on new hog farms and for the first

time set nitrogen discharge limits for municipal sewage treatment

plants. The state has also set up a rapid response team to investigate

fish kills and perform regular water testing on the Neuse. Preston

Howard is the director of North Carolina's Water Quality Division.

 

HOWARD: North Carolina's water quality environment has been on the

front page a lot lately, and having environmental issues on the front

page brings a lot of pressures on the agency to respond.

 

TOOMEY: But earlier this year North Carolina released a preliminary

report that said there are no human health effects and no connection

between pfisteria outbreaks and nitrogen pollution. The timing of the

release raised some eyebrows, coming as it did right before tourist

season and before the science was peer-reviewed. But now the state

seems to be open to the idea that pfisteria may be pollution-related.

Again, Water Quality Director Preston Howard.

 

HOWARD: Dr. Joanne Burkholder has done considerable research on

pfisteria, and has indicated that there is a connection between

nutrient enrichment and pfisteria. And it makes some sense, where you

have a nutrient source that you're going to get additional growth and

pfisteria's just one of those things that apparently likes nutrients.

 

TOOMEY: Dr. Burkholder and others say the relationship between

pfisteria and pollution is a complex one. It changes depending on what

life stage the organism is in. For one thing, nitrogen pollution

encourages the growth of algae, another food source for pfisteria.

 

(Boat motor)

 

DOVE: It's like diamonds all over the river, all those sparkling lights.

 

TOOMEY: As scientists continue to try to grasp pfisteria's strange

lifestyle, and as the state struggles with regulations, the Neuse

River Foundation is taking its fight for a cleaner river to the

Federal Government. It's suing for enforcement of the Clean Water Act.

Meanwhile, Rick Dove says there's still a lot of life here, despite

the degradation. And when he's not chasing down fish kills, the river

keeper tries to just enjoy the river he protects.

 

(Boat motor)

 

DOVE: Some of the prettiest sunsets you could ever find in North

Carolina are right here on the Neuse at this part of it.

 

TOOMEY: For Living on Earth, I'm Diane Toomey.

 

(Boat motor)

 

DOVE: Knock your socks off.

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