Posts tagged OEEFA
By Stephan Reed
During summer 2011, Robert Michael McKay, director of Bowling Green State University’s marine program, set sail on a research vessel on Lake Erie. The combination of no air conditioning and the July heat on the lake became unbearable, so McKay and his research team announced a swim call to cool off. Before jumping in, however, McKay noticed they were floating atop a large cloud of algae, full of the cyanobacteria microcystin.
This toxin irritates the skin, damages the liver, reduces oxygen levels in lake water, causes an unpleasant odor in drinking water and kills fish, according to a 2012 report from the Ohio Environmental Protection Agency.
Officials at the Ohio EPA are pushing for legislation that would advance the filtering systems in water treatment plants, especially when it comes to the harmful algae.
“There is a high concentration [of microcystin] in the water that comes into the plant, but a very low amount that comes out,” said Heather Raymond, the head of the harmful algal bloom task force for the Ohio EPA.
There are no mandated regulations concerning the toxin in drinking water, but the Ohio EPA has set in place unofficial regulations to help keep algae out of it, Raymond said.
“Everything we are doing is considered above and beyond the [federal Safe Drinking Water Act],” Raymond said. “These are unregulated toxins, but there’s enough data out there telling of the risk to human health. California came out with a threshold draft about Microcystin in water and it’s way below what Ohio’s is. We need consistency in our benchmark levels.”
McKay, while on his research expedition, realized these blooms were not only much larger than last year’s blooms, but they also arrived a few months early.
Blooms containing microcystis have always been in Lake Erie, but recently these toxic algae clouds have become more invasive than previous years, McKay said. This poses a potential threat to humans, pets, livestock and the Lake Erie tourism and recreation industry.
Despite the risks, McKay’s group had no choice but to dive into the harmful waters to avoid overheating.
“We eventually went swimming, but had to make sure we didn’t swallow any water,” McKay said. “It was the best of two really bad situations.”
The mass consumption of microcystis at one time can have a serious effect on the human body.
“If you took a big glass of the scum and drank it down,” McKay said, “you would probably have hemorrhaging in your liver. Your liver is basically a mass of cells and you have sinuses that carry blood throughout it. There are tight little tubes, and when exposed to microcystis, the capillaries begin to expand and blood begins to hemorrhage out of the liver.”
If a local community is using the lake for a drinking water supply, members of that community could face chronic effects due to prolonged exposure to the algae.
“Microcystin is a known tumor promoter,” McKay said. “It doesn’t start cancer, but if you have some cancerous cells and they go unregulated, microcystin can spread cancer in the body.”
Humans aren’t the only ones being affected by this toxin.
“This happens to animals, too,” McKay said. “You will sometimes find cattle and dogs drinking from the reservoir that has the bloom. They may take in a high enough dose and they will die due to the acute effects.”
The tourism and recreation industry has been negatively impacted as well.
Captain Joel Byer, of Nacho Fish Fishing Charter in Sandusky, Ohio, has seen deterred business as algae begins to bloom.
“This stuff doesn’t look good and it doesn’t smell good,” Byer said. “People see it on the news and they just don’t come to the lake. It was in the marina, and so thick around my boat, and it looked like a skipping stone could sit on top it. It looked like a can of thick pea soup washing up on the beaches.”
One way of approaching the problem is by attacking it at the source. McKay has narrowed down the cause of the large blooms to be the chemical phosphorous, which acts as a catalyst for algae.
“In most freshwater systems, algae are limited, but if you can give them one nutrient that will cause them to explode in growth, that would be phosphorous,” he said. “They seem to have enough of everything else.”
Phosphorous has been pinpointed as a major cause of algal blooms, McKay said. In the past, the government has issued regulation to decrease the amount of phosphorous contaminating the water.
“Sewage treatment plants weren’t effective in removing phosphorus, so phosphate was being loaded into the lakes,” he said. “Secondly, detergents have a lot of phosphorous in them. All that wastewater coming from washing machines was acting as fertilizer for algae.”
A third cause of phosphorous loading comes from large farms that use chemicals to feed crops and aid in the killing of invasive weeds, McKay said. The excess chemicals sink into the soil and are washed away into the water.
To avoid phosphorous getting to the water, farmers can put in “buffer strips,” or medians of grass between the field and the body of water, he said. The grass will grow rapidly but won’t let the chemical pass.
“A lot of people in Ohio have ponds in their backyards and some of those people use those for their water supply or for recreation,” McKay said. “In either case, people like to keep them clean. They don’t want that scum sitting on top. One approach is to install a strip of unmowed grass or reeds between the pond and the actual grass.”
However, there are some economic drawbacks for farmers when using this technique on a large scale.
“You want to maximize your yield on an acre, but then you have to give up 10 percent of your acre to a buffer strip,” McKay said. “Farmers might not like that, but other countries decided to use that approach because it has been used effectively. It has been used in China as well. Some of their lakes looked like you could walk on them [because of the abundant algae].”
Although the buffer strip method cuts down on the yield of crops for farmers, the United States government refunds farms that use this method.
Kyle Henry’s family farm in Perrysburg, Ohio, currently uses buffer strips.
“These are voluntary programs,” Henry said. “Farmers who use these receive subsidies. They do offset the costs, but with higher crop prices, there are some cases where farmers withdraw their buffers.”
Some farmers use manure as homemade fertilizer, said Andy Hupp, certification materials reviewer of the Ohio Ecological Food and Farm Association.
“A farmer isn’t going to use more fertilizer than needed, honestly, because it’s too expensive,” he said. “They’re not trying to load the water and soil with phosphorous.”
Farmers are not the only ones being blamed for the rapid growth in these blooms. The residential use of the herbicide Roundup contributes to phosphate loading into bodies of water, according to a 2009 research study published The Ohio State University’s magazine “Twineline.”
The issue of harmful algae blooms is apparent in other parts of the state. Grand Lake St. Marys, near Celina, Ohio, acts as the standing example of the treatment of blooms for the rest of the country. The lake was so bad that the government stepped in and placed great restrictions on the local farmers to help reduce phosphorous loading, Raymond said.
The chemical aluminum sulphate can be used to stop phosphorous from feeding the blooms. It has proven to be effective, yet costly, McKay said.
“They have done trials in 2010 and at the beginning of the last year,” he said. “They spread aluminum sulphate and measure its efficacy. They have found it to be effective so they have applied it over a large area on the lake. It’s a multi-million dollar application, so they have to weigh the return on the lake and the cost.”
This method may be effective in preventing blooms, but it could have harmful effects on wildlife, Byer said.
“Yeah, it’s cutting down on the blooms, but what’s it going to do to the fish?” he said.
Multiple strategies have been used to help Grand Lake St. Marys and have proven to be effective, however, some of the same strategies may not be used on the Great Lakes.
“Some of the protocol used on Grand Lake St. Marys will be used on Lake Erie, however, the politics are different,” McKay said. “With Lake Erie, you have two countries and multiple states dealing with it. Some of the approaches they are using on Grand Lake St. Mary’s probably won’t fly between states or between countries.”
The United States government has enacted laws that regulate phosphorous in household products. Americans currently use buffer strips in their backyards and farms to help keep phosphorous from reaching water.
While the idea of having an international lake with low levels of microcystin may seem to be a difficult task to accomplish, it is not impossible, Raymond said.
“There has been discussion about removing phosphorous from products on a small scale,” she said. “I do think it is possible to solve, but only with good management.”
View Areas with large algae blooms in a larger map