Harbor Sludge Might Hold Means to Clean The Anacostia River

How tough do you have to be to survive in Baltimore? Try breathing toxic waste instead of air.

That's what University of Maryland scientists have discovered a tiny microbe doing at the stinky, oily bottom of Charm City's stupendously polluted harbor. Down there, in muck as oozy as black jello, this creature can actually survive on PCBs -- one of the most harmful pollutants in U.S. waters -- and, in the process, break them down into something less dangerous.

Now, researchers are hoping to harness this nasty bit of nature's magic and use it to help other PCB-laden waterways, such as the Anacostia River. Their goal is to create a new kind of biological cleaning crew, bred from the original Baltimore stock.

"Up until now, nobody knew what to do with PCBs. They just lived with them," said Kevin Sowers, one of the scientists who led this research. "If we can do this, it will be the first time that we've been able to actually treat PCBs with a natural process."

This story begins at the Inner Harbor. It might look like a nice place to tourists, who generally stay above the waterline. But on the bottom, it's a different, much uglier story.

For decades, the harbor has been a catch basin for toxic dumping, gasoline leaks and runoff from dirty city streets. All that settled on the bottom to become a kind of super-sludge, which is to pollution what Washington is to lawyers. You could try, but you probably couldn't cram in any more.

"This is Baltimore Harbor," Sowers said one recent day in his laboratory, as researcher Birthe Kjellerup was opening a Mason jar full of black, viscous mud collected from the bottom. She was wearing gloves, since the stuff, and its rotten-egg smell, tends to linger on anything it touches.

"It'll be kind of a black coloration on your fingers, and it takes awhile to get it off," Sowers said. "It's like really black, oily ink."

Among the nastiness that suffuses this gunk are PCBs, whose full name is polychlorinated biphenyls. They are industrial chemicals, which were made from the 1920s until their manufacture was banned in 1977.

Over the years, PCBs were spilled into rivers, where they were eaten by bottom-feeding fish and then inadvertently eaten by creatures, including people, that eat fish. In humans, the chemicals have been linked to cancer and reproductive problems.

Health authorities warn against eating catfish from the Anacostia and Potomac rivers in Washington or eating the "mustard," or tomalley, in the innards of blue crabs from the mid-Chesapeake Bay, because of concerns about PCB contamination. Several other local waterways, including the Patuxent, Monocacy and Severn rivers, also have fish-consumption warnings because of these pollutants.

Scientists would like to get rid of the PCBs built up in these waters, but these chemicals were engineered so they would not break down. That used to be a good thing; now it's a problem.