Recent blooms of potentially toxic algae in the region's waterways have state officials warning people away from the greenish scum, which can get as thick as pea soup and sicken humans and animals.
Concerns sent state officials yesterday rushing to test the Chesapeake Bay's waters off Sandy Point State Park near Annapolis - a false alarm, it turned out, after the results came back negative for blue-green algae, said Peter J. Tango, a program manager tracking the algae blooms.
The tests, prompted by reports of blue-green algae in the bay from the park south to the Thomas Point Lighthouse, were the state's latest response to complaints about Microcystis algae. This week alone, blooms were reported near the mouth of the Severn, South and Magothy rivers in Anne Arundel County. They led to the closing since early August of Betterton Beach in Kent County.
This summer, concentrations of the algae have turned up in the upper bay waterways of the Bush, Northeast and Bohemia rivers, as well in the lower Eastern Shore's Transquaking and Chicamacomico rivers, and in the Potomac River, the Maryland Department of Natural Resources reported.
Health officials warn that contact with the blooms can lead to skin irritations, and drinking water containing the blooms can cause gastrointestinal distress. They said washing with fresh, clean water can prevent a rash.
Pets and livestock should not drink the water because the poison in the algae can cause liver damage and death. Children, they warn, are more at risk of illness than adults.
The public and physicians are asked to report illness and fish kills suspected of being caused by the algae blooms (888-584- 3110). State officials said yesterday they have not received reports of serious illness.
Tango blamed the algae blooms on conditions that foster the Microcystis algae growth: fresher water and plenty of nutrients in the still water. The algae enjoy the lower salinity - the water's salinity by the Bay Bridge is the lowest it has been since monitoring started in 1985 - and dine on the nutrients.
"This year we've got a situation where we've had snow runoff and extensive rain runoff into the summer," Tango said. "If water quality in the bay was better, you'd expect to have fewer blooms, lower-density blooms."
George Harman, program manager for environmental assessment and planning with the Maryland Department of the Environment, said the blooms may subside soon.
Sun staff writer Christopher Jack Hill contributed to this article.