Bay Is a Threat To Humans, Too
Report Cites Pollutants in Chesapeake
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 http:/
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.