Algae blooms an issue globally

115 scientists attend BGSU symposium

Rick Stumpf, of NOAA, speaks during a major algae conference in Olscamp Hall at Bowling Green State University.

BOWLING GREEN — From Europe to Asia to Africa, Lake Erie is interconnected with the world through algae.

As one case study of algae blooms after another was presented Tuesday during the second and final day of a major international algae symposium at Bowling Green State University, it became more clear that the problem that kept nearly 500,000 Toledo water customers from drinking tap water the first weekend of last August is hardly unique.

Scientists believe the threat is growing and could happen almost anywhere as more of the world’s farmers are under pressure to produce food, more land is being overly developed, Earth’s population is growing, and the planet’s climate is warming.

Data was presented about lakes in Austria, Norway, Sweden, Denmark, Switzerland, the Netherlands, Germany, Spain, China, Japan, South Korea, Uganda, and other countries, as well as many other parts of North America.

Although there are numerous forms of algae, some of them healthy, dangerous blooms known as cyanobacteria, or blue-green algae, are popping up many places in the form of microcystis, the most dominant form of western Lake Erie algae the past 20 years, and a lesser-known form of algae in the lake’s Sandusky Bay known as planktothrix. Microcystis and planktothrix both produce microcystin, one of the most potent toxins in nature.

Some stay active far longer than the four or five months a year that microcystis typically stays in bloom in Lake Erie. At Lake Taihu in China, microcystis can bloom nine months of the year, according to Hans Paerl, a distinguished marine and environmental sciences professor at the University of North Carolina-Chapel Hill, who has studied algae there.

Rainer Kurmayer, an algae researcher at Universtat Innsbruck in Austria, told 115 scientists from 15 states and five countries at the event how there is strong genetic proof that those and other forms of toxic algae are almost as old as Earth itself.

An overabundance of nutrients and changing climate has helped them grow beyond manageable levels, scientists said.

Petra Visser, an algae researcher at the University of Amsterdam in The Netherlands, said her country has a difficult fight against algae because of its heavy agriculture and dense populations in tight land mass. The Netherlands “has a reputation for being active in water management” because it is below sea level, she said.

She cited several examples of efforts to address algal blooms, from traditional treatment to using pumps to aerate, flush, or artificially mix water. Algae has trouble blooming in agitated water.

In Lake Koetshuis near Veendam, large amounts of diluted hydrogen peroxide were used in a 2007 research project to neutralize algae. The hydrogen peroxide quickly dissolved with the algae, leaving the water safe, she said.

“In a couple of days, we could open the lake again and there were hardly any cyanobacteria at all,” Ms. Visser said. “It seems quite easy and quite logical, but we still have a lot of questions to answer.”

Tom Kovacik, a chemist who once served as Toledo’s public utilities director, said he believes hydrogen peroxide has exciting possibilities as a backup weapon against algal toxins the next time they get blown together and overwhelm the city’s raw-water intake.

But Greg Boyer, a State University of New York chemistry professor, said he is 3.5 years into the “regulatory morass” of trying to get permits from the state of New York for a hydrogen peroxide research project because that state classifies it as a pesticide. “It’s been a 3.5-year odyssey of things I never wanted to learn,” Mr. Boyer said.

Scientists said such treatments should not be done in place of addressing the core problem of nutrient runoff.

Lake Erie is too large for many treatments, Tom Bridgeman, a University of Toledo algae researcher, said.

Said Mr. Paerl: “No matter how you slice and dice it chemically, you’re still going to have to deal with [nutrient] inputs.”

Contact Tom Henry at: thenry@theblade.com, 419-724-6079, or via Twitter @ecowriterohio.