From the Newport News-Times
June 5, 2009
A group of community members who reside within the Devils Lake Water Improvement District (DLWID) are questioning whether cyanobacteria blooms, blue-green algae that has the potential to release harmful toxins, are really an issue for the Lincoln City lake, and suggest that Lake Manager Paul Robertson’s testing procedures may be inaccurate. The group, which maintains a website at www.nosolarbees.com, has asked the board to abandon plans to install 20 SolarBees, solar-powered water circulation devices meant to combat blue-green algae. The cost of the project tops $1 million.
The shallow, 685-acre coastal lake sees cyanobacteria blooms for much of the year, Robertson stated recently, with the onset typically occurring in early August. When blooms are present, there is a potential for toxins to be produced. Algal blooms, blankets of floating scum, may or may not excrete toxins. Robertson posted a red health advisory warning people to stay out of the water at Devils Lake parks last August, claiming that analyses performed on water samples taken from the lake determined that a high quantity of microcystin, a known liver toxin, was present.
The advisory remained posted for weeks into the fall. Oregon Department of Health and Human Services protocol states that an advisory should be posted if microcystin level than 8 parts per billion. Robertson claimed in a press release last summer that one test showed microcystin present at levels greater than 100 ppb, nearly 13 times the recreational water use standard of 8 ppb set by DHS. Mitchell Moore, a DLWID budget committee member, said his Beaverton family visits their Devils Lake home every couple of weeks in the winter.
During the summer, Moore’s wife, Dana, and their three kids aged 18, 21 and 23, are full-time residents. “My daughter has been swimming in that lake since she was 8-years-old,” Moore said. “She’s never gotten sick. People have lived on the lake for 50 years and never gotten sick. “You see the green slime, and you attempt to avoid it. Not so much because you’re afraid of dying, but because you go ‘Ew’.”
Moore said he has seen Robertson taking water samples from the middle of blooms. Moore would rather Robertson tested areas of the lake that people are most likely to recreate in. “Paul samples the worst case areas,” Moore said. “I think Paul should test samples taken from places other than 14 inches from the shore. “I think his data should be reviewed. There should be some independent testing.”
Despite the presence of the red health advisories warning people to stay out of the lake, the City of Lincoln City went ahead with its annual triathlon last September, which includes a swim in Devils Lake. The nosolarbees website states that “While DLWID posted cyano-watches for many weeks last summer, much of that time the average citizen would have deemed the lake clear.” Jon Stanley, a Devils Lake homeowner, posted a note on the nosolarbees website in mid-May. “DLWID wants $1 million to fund a project […] to prevent a problem that is not a problem,” Stanley wrote. “Where are the lake closures and illnesses? […] “Is this the best use of tax dollars in this climate? SolarBees might be a choice. But at this time, at this particular lake, they are the wrong choice.”
Cyanobacteria has been around for 3.5 billion years, but it’s only been receiving attention in the last four years or so, Robertson said. “It’s been getting what seems to be a lot worse,” he said. “Bodies of water are more polluted.” Global warming may be influencing an increase in toxins, said Ken Kauffman, DHS Environmental Toxicology program. A couple of degrees of annual ambient temperature can make a significant difference in the biological activities in water. “There’s a growing concern about cyanobacteria toxins,” he said. “You may think you are hearing more about it, but that’s because more people are studying it.”
DLWID’s Cyano-Watch program uses ELISA, enzyme-linked immunosorbent assay, to test for microcystin. ELISA is a simple, common biochemical diagnostic test used in multiple industries.Test-specific enzymes produce a color reaction with the toxin being tested for, and the intensity of the color is proportional to the concentration of the toxins in the sample. The results are read with a microplate reader. Green Water Laboratories CyanoLab, an aquatic analysis, research and consulting company in Palatka, Florida, is the only private full-service laboratory of its kind in the United States.
Green Water Laboratories uses LC Mass Specs, liquid chromatography and mass spectrometry instruments, to identify specific cyanotoxins. The lab’s scientists then use ELISA assays to quantify the amount of toxins present.
The company’s president, Chris Williams, has a PhD in aquatic toxicology. He confirmed that ELISA kits are reliable, but said that can depend on how well the technician performs the testing, as well as the composition of the water itself. Sometimes things in the water can interfere with results. Kauffman said the ELISA assay is reliable and accurate, but admitted that the general public might have more trust in results from an independent, accredited lab. “You would have less people questioning his results,” Kauffman said. “I don’t question his findings at all.” Kauffman said it’s important to test samples from the most affected areas of the lake. “There are tremendous variations in any body of water,” he said. “It’s possible to have unaffected areas, but you want to know the worst case scenario.”
Are people who swim in Devils Lake being exposed to cyanotoxins? Can they tell if they have been exposed? “It’s complicated,” Kauffman said. “No one can say that they haven’t been affected by these toxins.” The symptoms of toxin poisoning are fairly nonspecific, added Kauffman. An illness from exposure to toxins could be misdiagnosed as the flu. “You can get sick from acute exposure and recover,” he said. “It’s not a reportable illness because it’s extremely difficult to diagnose. Diagnosis would require a liver biopsy and that is too extreme to conduct on a living person. “However, there are chronic affectsthat don’t become apparent for years and years. The effects are progressive and don’t become noticeable immediately.” Williams said the State of Oregon’s standard of 8 ppb is very conservative.
The federal government has not yet set standards, but the World Health Organization’s suggestedguid eline for microcystin is above 20 ppb. Above that level, people should stay away from bloom areas, he said. “We don’t feel there’s much danger if microcystin levels are under 100 ppb,” Williams said.
“Toxins are isolated within the algal cell, and, in general, toxins are not going to come into contact with the skin. “Some people might get a rash, but normally, unless people get a big gulp of water from within the bloom itself, we generally don’t see a lot of health problems.” However, he added, there haven’t been a lot of studies done yet, so there is room for caution.“Scientists are currently studying the recreational effects of toxins, but the study is in its infancy,” Williams said. “Oregon is being conservative. They’re looking out for the health of people. That’s a good thing. “I personally would say that if you stayed away from the blooms you would probably be fine. But you don’t want that one person going in there and having a bad reaction.”
Williams added that he could understand why DLWID wants to address the cyanobacteria problem, but that water circulation devices may not be the best solution. It’s possible that SolarBees can combat cyanobacteria, but it depends on the individual lake, he said. Water circulation wouldn’t be as effective in shallow lakes. “Blue-green algae thrive on no motion and plenty of nutrients,”
Williams said. “You have to limit the nutrients. Water circulation devices stir up sediment, and release even more nutrients into the water. That creates more cyanobacteria blooms. “Personally, I would think Devils Lake would want a guarantee that the technology will work in their lake before they invest in it. That’s a lot of money. If I was a lake manager, I would like to know it would work.”