Bay Is a Threat To Humans, Too
Report Cites Pollutants in Chesapeake

By David A. Fahrenthold
Washington Post Staff Writer
Tuesday, July 7, 2009

The same pollution problems that afflict the Chesapeake Bay's fish and crabs -- high levels of mercury in fish, neon-colored algae blooms and voracious bacteria -- can also threaten the health of people who fish, boat and swim in the estuary, according to a new report.

The report, released today by the nonprofit Chesapeake Bay Foundation, pointed out that the threat of infection from pollutants that wash into the bay from onshore is great enough that health authorities recommend not swimming until 48 hours after a significant rain.

It says that many of the Chesapeake's problems have not improved significantly, despite a government-sponsored "save the bay" effort now 25 years old. And with climate change apparently warming the water to a more pathogen-friendly temperature, it says one of the scariest health threats -- a powerful strain of bacteria called Vibrio -- may become more common.

"Clean water laws are not being enforced, and this is putting human health in danger," said William C. Baker, the foundation's president. Baker said the information about Vibrio was among the report's most disturbing conclusions: "I was surprised . . . that there are very real, very severe risks in contact with the waters of Chesapeake Bay."

Clifford S. Mitchell, director of environmental health coordination, for Maryland's health department, downplayed the risks to swimmers, saying, "We're not seeing any kind of indication that it's not safe to go into the Chesapeake generally." He also said the agency had not recorded any cases of food poisoning related to Chesapeake shellfish between 2001 and 2007. He said he did not have the 2008 figures with him.

Nevertheless, Mitchell acknowledged that swimmers should avoid water activities after a rain, which can sweep in animal manure and human waste from older sewage systems and leaky septic tanks. He also warned that people should not let cuts or open wounds contact the water; should avoid water that is unusually murky or discolored by algae, and should check official signs and Web sites for state water-quality warnings.

"If the water looks good, if there are no postings [warning not to swim], if they've checked online . . . they should feel pretty comfortable," Mitchell said.

Maryland officials recommend that would-be bathers download a Google Earth program that notifies them about beach closures. It can be found at In Virginia, information about bay beaches can be found at

The bay foundation's report highlights several threats stemming from pollution:

-- Blooms of cyanobacteria, also known as blue-green algae, can cause liver disease, skin rashes, nausea and vomiting if ingested. The foundation's study said that, in 31 percent of tests on water contaminated with the algae, there was enough to make the water unsafe for children to swim.

-- A protozoan called Cryptosporidium, which washes into the bay in human and animal waste, can cause diarrhea and sometimes more serious illnesses if ingested.

-- Mercury, found in the smoke from coal-burning power plants, winds up in the water and accumulates up the food chain. People who consume enough of it can suffer neurological damage and an increased risk of heart disease. Mercury is the reason that state authorities warn against consuming too much of certain fish from lakes and streams in this region, and advise diners to limit their consumption of rockfish from the bay.

-- Vibrio, typically found in warmer waters to the south, seems to turn up more often now in the Chesapeake, the foundation's report said. The reason could be climate change and algae blooms that make the water more inviting for the bacteria. In Virginia, for instance, the report said, the number of cases of human infection jumped from 12 in 1999 to 30 in 2008. Vibrio can cause vomiting and diarrhea if ingested, and potentially serious skin infections if it is contracted through open wounds.

But Mitchell, from the Maryland health department, said that there were not enough data to know if these infections really are more common than before.

Among those who have been infected is Ken Smith, vice president of the Virginia Waterman's Association. Smith said that in June of last year, he had been removing big "Jimmy" crabs from his pots, then washed up with a bucket of water from Totuskey Creek, a tributary of the Rappahannock River.

The next morning, he woke up and saw a bump on his forearm the size of a mosquito bite.

"Went and drank a cup of coffee, and I looked back down and it was about the size of an egg," Smith said. In a few minutes, he was shaking violently, and drove himself to a hospital in Kilmarnock, Va. Smith said doctors there had seen enough cases to know it was Vibrio. But even with treatment, he endured several painful days, in which his infected arm swelled up twice the size of the other one.

"It's got to be something . . . in the water that [Vibrio] likes," Smith said. "It's just too much of it happening here."


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