- The Washington Times - Thursday, August 31, 2000

Scientists slowly cruised along the Anacostia River in Southeast D.C. yesterday in one in a series of visits to determine whether the river's polluted waters are causing the ill health of the area's catfish.

So far the results of their two-month-long study don't look too promising: The sick fish appear to be living in the Anacostia River, which means the condition of the polluted river may be the leading cause of their health problems.

"We were trying to find whether the pollution is more of a regional problem," said Fred Pinkney, an environmental contaminants biologist with the U.S. Fish and Wildlife Service, the federal agency that's leading the study.

"So far, it appears to be localized," Mr. Pinkney said, who stood on the Anacostia boat ramp yesterday afternoon as his team of researchers climbed into a motorboat to begin their experiment.

"But we want to get a couple of more seasons to study this before we can make that final determination."

Mr. Pinkney and his researchers began tracking a group of 10 brown bullhead catfish July 20, after two studies conducted over the past decade found that more than half of the catfish caught in the Anacostia River had liver tumors.

"I think these results indicate the seriousness of the problem in the Anacostia," Mr. Pinkney said.

Tumor rates in freshwater and saltwater fish have been used as an indicator of pollution. Experts say anything over 9 percent indicates high levels of pollution.

The most recent study, completed in 1996, found that 55 percent of the 60 catfish caught swimming in the Anacostia River had liver tumors. Most of the tumors were microscopic; however, some measured nearly a centimeter long, said John Harshbarger, a fish pathologist at George Washington University Medical Center, who conducted one of the studies.

"If 55 percent of people had liver tumors, they'd be worried about it," Mr. Harshbarger said.

"It would be a catastrophe. This is much the same way, except we're dealing with fish."

The same study found another 37 percent of the fish had skin tumors. Experts say bullhead catfish with skin tumor rates over 20 percent are almost always found in contaminated areas.

The test results were worse in 1991, when Mr. Harshbarger found that 75 percent of the Anacostia River fish he surveyed had liver tumors.

"That's a very high rate," Mr. Harshbarger said. In low-pollution sites, scientists may find that only 2 percent to 3 percent of 50 fish tested will have liver tumors.

Experts say tumors are caused by exposure to cancer-causing chemicals, like oil, diesel fuel, gas and coal tar, that flow into the rivers and accumulate in sediments.

The bullhead catfish typically feed on worms and other invertebrates found on the river's bottom and bury themselves in mud during the winter.

"We want to use the rate of tumors as a yardstick on how polluted the Anacostia River really is," Mr. Pinkney said.

Officials with the National Park Service said yesterday they became concerned when they learned of the results.

"We're very concerned with what's happening with the fish there," said Janet Braxton, a spokeswoman with the National Park Service-National Parks East. "We're now doing everything we can to test the waters and to keep the public aware of the concerns."

As a result, the D.C. government issued an advisory in the mid-1990s against eating fish caught from the city portions of the Anacostia and Potomac rivers.

After studying the data, the team of researchers wanted to find out whether those fish actually live in the Anacostia, which has been rated among environmental experts as one of the 10 most polluted rivers in the country, or do they swim upstream from the Potomac.

To conduct the experiment, researchers last spring caught 10 catfish, surgically implanted a tiny transmitter the size of a AA battery into each of them and released them back into the river.

Now, the group goes back three times a week for five or six hours until the end of next month to track the movements of these fish. And during each visit, a crew of two researchers, wearing headphones, climb into a tiny white motorboat and with a highly sensitive underwater microphone catch ultrasonic signals emitted by the transmitters in the catfish.

So far, nine out of the 10 catfish have been found within a one-mile radius of the boat ramp off Anacostia Road, where the fish were released, Mr. Pinkney said. None of the fish has been found going beyond the 11th Street Bridge.

The study was co-sponsored by the D.C. Department of Health, which will use the data and develop a strategy to reduce the amount of cancer-causing chemicals entering the river, said Theodore Gordon, the city health department's senior deputy director for public health assurance.

"This data will help us make the waters clean and maybe swimmable, some day," Mr. Gordon said.

First, the health department plans to establish pollution-control limits on waterways including Hickey Run that flows through the National Arboretum in Northeast D.C., which is expected to sign an agreement with the city to build a pollution control device that will help stop chemicals from entering the waterways.

The Health Department also has required Washington Gas, which sits on the waterfront, to install additional wells that would catch coal tar and treat it before releasing the water into the river, Mr. Gordon said.

Researchers hope to come back next spring and fall to continue their study of the Anacostia fish. If they get enough funding, they also want to conduct another tumor survey, Mr. Pinkney said.

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