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| April 18, 2011 Post 24 |
| something in the water |
Boaters- I promise to give the environmental topics a rest after this one. Watch for news about an entertaining sailing memoir about living on the edge with an old wooden boat-coming soon!
Discover Magazine 'broke' this story recently though a search of the Internet turns up a number of articles on the topic since publication of a 2003 scientific paper first suggested blue greens might effect on development of various forms of dementia. Because of my involvement with the water quality impacts of agriculture, I picked up on the magazine story sent along by a friend. Blue green algae blooms have been on the increase generally in the Great Lakes (and elsewhere)for a decade or more. One reason appears to be excessive inputs of fertilizers from farm fields. As I wrote in my SPOT.US feature published this month reactive phosphate inputs to Lake Erie from the Sandusky and Maumee Rivers last summer were at an all-time high since the start of a Heidleberg College tributary monitoring program that began in 1975. And last summer blue green blooms on both Lakes Erie and Ontario were extensive.
BMAA,beta-n-methylamino-L-alanine, is a non protein amino acid produced by many cyanobacteria (blue green algae). These primitive organisms live on soil, within plants and lichens, and in freshwater and marine environments. BMAA has been found in high concentrations in the brains of ALS/Parkinson's disease and dementia “complex†and Alzheimer's victims. It appears that some people apparently lack the genetics to break this molecule down, so it builds to harmful levels in their brains.
A lot of people have been trying to figure out for awhile how dementia happens. Clusters provide clues because they suggest that environmental factors play a role. A cluster famous in the medical literature is that of Guam where many people suffered from various forms of dementia, Parkinson's disease like conditions and other diseases. The neurologist Oliver Sacks wrote about this in his book “The Island of the Colorblind†where the incidences of disease were 100 times higher than in the general population. At that point the smoking gun hadn't been found though the cycad seeds were then suspected. But it now appears that BMAA was also concentrated in the food chain. In the Proceedings of the National Academy of Science in 2003, Paul Cox et. al described the process.
Blue green algae that fix nitrogen and live as beneficial symbionts on Cycad tree tissues produced BMAA that was concentrated in the Cycad seeds. These were then used for flour by people or were eaten by animals (like fruit bats and pigs) that bioaccumulated the substance a 1000 fold. These then were eaten by people. In fact, according to Paul Cox's paper, the people liked Flying Foxes so much that after the U.S. took over Guam as a military base and guns and cash were readily available they promptly shot and ate up almost all their flying foxes. A lot of the people then got sick and eventually died of degenerative diseases. In recent years the diseases have been in decline. I guess most of the bats are gone now, so nobody is eating bat anymore.
Now it appears other ALS/dementia clusters are being discovered and investigated including one around a lake in New Hampshire. The Mascoma lake cluster shows ALS at a rate of 25 times higher than the national 2 per 100,000 norm. Mascoma Lake in the past had fairly regular blue green algae blooms, but a Google search on the story turned up reassurances by local elected officials that it's all fixed now. The lake is nice and clean. No more pollution or algae blooms. Too bad more of the nation's waters can't say the same.
A natural question to ask Google is how dangerous is BMAA in our drinking water. One suspects that like the fat soluble toxins in our lake the concentration of it in water would be far lower than in fish. And since it's a molecule one wonders what kind of filtration system you need to take it out. Probably not something that the town water plant has. The Foundation for Water Research website had a report for city water and sewer plant operators dated in 2008 that said essentially yeah, this could be bad but we don't know so we ought to do more research. Fat Chance with the Tea Party in office now, of getting that grant any time soon.
Epidemiological studies such as are needed here are expensive and because of the politics of the world often hard to get grants for. It's a bit like long term exposures to low levels of radiation. No one is very eager to destroy the nuclear industry. And likewise, the real estate business wouldn't be too thrilled if blue green algae hysteria swept the waterfront home market. But careful studies and good statistics are the only way to prove a link between factors and diseases like these. And once the cause or contributing factor is known, we could take actions to prevent the tragedies of ALS, Alzheimers and Parkinson's disease.
An interesting article by a consultant in South Africa on cyanobacteria and BMAA is at this location.
http://blog.dhec.co.za/about/