Cooperative Extension Ready With Algae Test Kits

LINCOLN , Neb. – This summer will likely see more toxic blue-green algae blooms, many of which were reported on Nebraska lakes and ponds last year and which can be a serious threat to human health and to animals.

Last spring and summer saw an explosion of toxic blue-green algae blooms on ponds and lakes across Nebraska , particularly in eastern Nebraska where recreational use of these water bodies can be very high.

Skin irritations and gastrointestinal problems are the main risks to people from algal toxins, but in rare cases, extremely high toxin levels can be fatal to people.

Last year’s blooms resulted in only a few reported cases of human illness and

skin irritation and some livestock and pets died after drinking lake water during an algae bloom, said UNL water quality specialist John Holz.  

There was an unusually high number of complaints about blooms last summer, particularly in May and June, but persisting through the summer months,” said UNL water resources specialist Tadd Barrow.

The normal season for algae bloom complaints is June through September. Last year the toxins and blooms began appearing in May and persisted through September. Some lakes still had blooms and high toxin levels as late as December, Barrow said.

With forecasts calling for similar weather patterns this summer, he predicts “Blooms will be just as prevalent as last year. Higher public awareness of the problem could also result in more of the blooms being reported.”

Due to the probability of more toxic algae blooms this summer, Nebraska Cooperative Extension’s lake management program is continuing a volunteer monitoring program to check lakes for blue-green algae. Free test kits are again available from Barrow’s office so lake owners, users and managers can check their lake for potential toxin-producing algae, Barrow said.

Last year, more than 400 of the free kits were sent to testers all across Nebraska, Barrow said. About 40 percent of those that were returned to the university for testing were positive for the presence of potential toxin producing blue-green algae.

Fifty-five water samples the university received tested positive for blue-green algae, 20 of which were above the two parts per billion limit set by the Nebraska Department of Environmental Quality.  All 55 of those samples were sent to the NDEQ, which tests for blue-green algae toxin and tracks blooms across the state, Barrow said.

The number of kits sent out doesn’t include the second, third, fourth or more samples tested for some individual lakes and ponds,” he added.

Kits contain instructions on proper sample collection, a sheet for recording measurements, a questionnaire about the lake, and sample bottles for water and algae.  Samples are returned to Barrow for processing and those who submit samples are notified of results.

For more information or a test kit call Hilary Hansen at (402) 472-8190 or go to the UNL Water Center web site at http://watercenter.unl.edu/.

Knowing what an algae bloom looks like and avoiding water contact during blooms is important, the two School of Natural Resources experts said.

People should avoid swimming, water skiing, riding personal watercraft or similar activities involving physical contact or swallowing water from lakes with blue-green algae blooms, Holz said.

During a bloom, lake water becomes cloudy with a green or blue-green cast and blue-green streaks may be visible on the water’s surface, said Kyle Hoagland, a lake ecologist who heads UNL’s Water Center.

At this stage, the lake looks like pea soup or as if someone dumped a light colored green paint in the water.  It often develops a strong musty or fishy odor as the algae accumulates and begins to decompose," he said.

Winds can increase the danger of a toxic bloom by blowing algae to the leeward side of a lake where it concentrates in coves or along shorelines.

Blue-green algae, which are cyanobacteria, are microscopic organisms commonly found in lakes and ponds worldwide.  Special characteristics of blue-green algae often allow them to multiply faster than other types of algae, Holz said.

Rapid algal growth is called an algae bloom. Blooms can appear and linger anywhere from days to weeks and can persist until the first hard frost in the fall, Hoagland said. 

Some types of blue-green algae produce chemical toxins that harm people and animals. “These colorless and odorless toxins may linger in the water for as long as two weeks after the bloom has disappeared.”

Numerous environmental factors can trigger a bloom, lakes with higher concentrations of nutrients, or fertilizers, especially phosphorus, generally tend to be more susceptible to blue-green blooms, he added.

Sources:

• Kyle Hoagland, Ph.D., professor, School of Natural Resources; UNL Water Center director, (402) 472-3305
• John Holz, Ph.D., research assistant professor, School of Natural Resources, (402) 472-6648
• Tadd Barrow, water resources specialist, School of Natural Resources, (402) 472-7783
• Writer: Steve Ress, communications coordinator, UNL Water Center, (402) 472-3305, sress1@unl.edu