As trucks clattered over a bridge nearby, Raymond Green, 76, hauled a motorboat brimming with dozens of freshly caught blue crabs out of the oil-slicked waters of the Middle Branch and up a littered boat ramp.
In the parking lot of South Baltimore's Broening Park, he was approached by a pair of health outreach workers from the Maryland Department of the Environment, who were making an effort this week to contact urban fishermen.
In new pamphlets and posters, the state is proclaiming that meat from crabs pulled out of the polluted waters of the Patapsco River and Baltimore Harbor is safe to eat -- adults can consume as many as eight meals a month -- as long as people avoid eating the liverlike organ called the "mustard."
But as the outreach workers found, many inner-city watermen -- some of them unlicensed, older and devoted to savoring the highly prized, flavorful, oozy yellow-green crab hepatopancreas -- tend to be snappish when told to change their eating rituals.
"I'm gonna keep eating it, and if I die, I'll die happy," Green, a retired toolmaker, said of eating the crab mustard. "I've been doing this for 100 years, and it ain't killed me yet."
"Tough old bird," said state toxicologist Joseph R. Beaman as he walked away to staple a poster on a piling beside the boat launch.
The sign, like many others being raised along Baltimore's waterfront, said: "Health Advisory: Baltimore Harbor." The posters say people should avoid eating carp, catfish and eel from the Patapsco River and Baltimore Harbor.
Adults can eat up to four meals a month of white perch from these waterways, but children and women of childbearing age should avoid them, according to the state's new pamphlets.
Adults can also eat up to eight meals a month of crabs from those waterways -- four times the amount under the most recent guidelines, which were issued in 2001, according to the MDE. Children can eat up to two meals. There is no limit for crabs caught elsewhere in the Chesapeake Bay.
Beaman, section head for ecotoxicology and standards for the MDE, said man-made toxins called PCBs are sometimes found in the mustard of crabs pulled from the harbor or the Patapsco River. Exposure to PCBs has been linked to cancer. PCBs are chemicals that are used as a coolant in electric transformers (among other machines), and they leak into storm-water drains when transformers blow, Beaman said.
"It's OK to eat more of the crab, but just don't eat the mustard -- I can't emphasize that last part enough, being a toxicologist," Beaman said.
The guidelines for eating crabs were liberalized not because the harbor is cleaner, but because new and improved tests separated the crabmeat from the mustard, Beaman said. The old test mixed the PCB-laden mustard with the meat.
At Canton Waterfront Park, Beaman and an assistant stapled a sign to a pier and talked with Tony Storto, a 60-year-old retired firefighter and frequent fisherman.
Storto said he knew a thing or two about the harbor's pollution. He recalled when he was a kid growing up among the fertilizer plants and canneries of Canton's industrial waterfront.
One time, Storto said, he lugged home a dozen crabs he'd pulled out of the oily, sewage-streaked murk.
"My mom steamed 'em up, and then she found a half-inch of oily, greasy stuff in the bottom of the pot. She screamed at me, 'Don't you ever bring those harbor crabs into my house again!'" Storto said.
"I've caught a lot of nice rockfish out of the Patapsco, but I'd never eat crabs out of here," he said.
Beaman handed him a brochure. "Actually, the crabmeat is OK out of here, but we advise not to eat the mustard."
"I love the mustard," Storto replied. "A lot of people consider it a delicacy, like scrapple."
At the trash-strewn waterfront in Ferry Bar Park, Robert Cheatham, 66, leaned against a rotting log, with two fishing poles propped in front of him. When the state workers approached, Cheatham tugged a length of twine out of the harbor. From the bobbing trash emerged his catch of the day: a white perch, 6 inches long.
"I'll take this guy home and fry him right up," said Cheatham, a retired construction worker, who sat near an overflowing trash barrel behind a Wal-Mart store.
Beaman gave him some advice on how to cook it.
"We recommend against frying, because it locks in the contaminants," Beaman said. "We recommend that you remove the skin, and then broil, grill or bake it."
The guidelines for fish and crabs from the Patapsco River and Baltimore Harbor are:
Crabmeat: Up to eight meals a month for adults; two a month for children.
Mustard from crabs: Avoid.
Carp, catfish and eel: Avoid.
White perch: Four meals per month for adults; women of childbearing age and children should avoid.