Monday, August 23, 2010

"Scientists say the toxic blue-green algae will only get worse on Ohio lakes"

From Cleveland.com:

The simmering summer of 2010 is coughing up a sickly and unprecedented batch of toxic blue-green algae in western Lake Erie and nearly a dozen of Ohio's shallow, inland lakes.

Many lake scientists are speculating that it's only going to get worse.

"We're going to see a greener and greener lake until changes are made," said John Hageman of Stone Laboratory, Ohio State University's water research station on Gibraltar Island in western Lake Erie. "Everything points to this just getting worse."
That might be hard to imagine.

But it could help to survey the squalid situation at Grand Lake St. Mary's -- a large, inland lake in western Ohio. The 13,000-acre lake near Celina grabbed the attention of both the public and health officials all summer long because of its toxic, pea-soup waters and foamy surface.

"Grand Lake St. Mary's has gone green every summer for decades, that's not new," said EPA spokeswoman Dina Pierce. "But this year, it just exploded -- at times it looked like a science fiction landscape, almost turquoise or swimming pool blue with white foam on top.

"People who have lived there their whole lives had never seen anything like it."

But while the Great Lake and the big lake near Celina have grabbed the headlines, in recent weeks it seems as if almost any shallow body of warmer water in Ohio might be at risk from being tainted by a floating, green bloom of algae.

Simply put, the 2010 algae outbreak is breaking the mold.

"This is first year we've seen blooms like this -- all across the state," said Jen House of the Ohio Department of Health, which is working with the EPA and state Department of Natural Resources to coordinate warnings at the various lakes and Lake Erie beaches. "The problem is that this bacteria loves warm, sunny weather and we've had plenty of that."

State officials have posted warnings about the dangers of coming in contact with blue-green algae at sites from West Branch State Park in Portage County (later found to be free of blue-green algae) to East Harbor State Park on the shores of Lake Erie's warm and shallow western basin.

Ohio health and recreation officials have received about 30 complaints linked to human sickness or irritation from exposure to algae -- more than half from Grand Lake St. Mary's, where officials have long known that runoff from animal feeding operations is providing nutrients for the algae to grow.

At least three dogs have also reportedly been killed by exposure to the blue-green algae in the Ohio lake. Those pet deaths followed similar algae-related dog deaths in recent years in Minnesota, Illinois and Indiana.

Scientists on Lake Erie, where most of the research takes place, blame high concentrations of phosphorus and high water temperatures for algal blooms on course to be the worst in 30 or 40 years. Most say those same factors are playing a role in the algal blooms on the inland lakes.

The dissolved phosphorus count -- fertilizer runoff from farms in Ohio, Indiana and Michigan -- flowing out of the Maumee River is the highest since records began in 1975, according to records at Heidelberg University...

The temperature increase, meanwhile, appears to be merely following a long-term trend that many attribute to a slowly increasing global climate. Water temperatures in Lake Erie and the other Great Lakes have been extraordinarily high since a record warm spring.

Satellite images have shown similar algal growth in each of the last few summers - the largest outbreaks since the blooms reappeared in the mid 1990s, after disappearing for more than 15 years in the wake of the more stringent water quality laws of the early 1970s.

The algae that bloom by midsummer and often stays through September is not only unsightly, but can threaten both fisheries and tourism because the worst strain -- the bacterial microcystin, known as blue-green algae -- can unexpectedly turn toxic about half the time.

"This is a Lake Erie-wide issue, at least," said Gail Hesse of the Ohio EPA's Division of Surface Water and head of the Ohio Lake Erie Phosphoous Task Force. "This lake is water resource for all of Ohio, so we should all have be concerned because the algae can be a public health concern when it goes toxic."

An algal bloom isn't just a natural wonder and contributor to the dead zone. It's potentially fatal.

Blue-green algae -- actually the peptides secreted by certain blue-green algae known as microcystis -- is a known neurotoxin, meaning that at high concentrations it can severely damage the nervous system, including the brain. That makes it especially dangerous to small children or those with weak immune systems.

While there are currently no official health standards for microcystin, state officials are posting warnings based on those recommended by the World Health Organization: No more than 20 parts per billion for recreational water and 1 part per billon for drinking water.

Grand Lake St. Mary's blew those standards out of the water.

"Last year microcystin was already sky high at 84 parts per billion," Hesse said. "Then, early this year, we had readings over 2,000 -- that's on a whole different scale, unimaginable until now."

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