Toxic Bloom Despite Josh Bloom’s Rosy Views

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Satellite shot of Lake Erie, revealing an algal bloom from previous year when winds did not bring algae close enough to the reservoir. This year(2014), they were not so lucky.

Since the early 1980s, the media has played a roller coaster game with the coverage of environmental issues. The public’s appetite for such coverage seems to unfortunately ride the waves of economic growth and recessions.  Meanwhile groups at each end of the spectrum play political games and distort realities that are difficult to pin down. As a result, the environmental movement has been scattered, and its less admirable fragments are perceived as being representative of the whole.

Here’s a comment from a blog by Josh Bloom, an experienced, ex-pharmaceutical chemist who has some strange things to say about environmentalists. It’s from the comment thread of his post entitled Environmentalists Killed My Friend , which describes how one particular Long Island, NY community refused to spray mosquitoes. Eventually his friend caught West Nile encephalitis. This made him emotional, but he echoed a common and deeply flawed sentiment.

I consider myself to be a rather serious environmentalist. But a practical one. Anything that can reasonably be done to materially decrease air and water pollution is great.
But this when this turns into dealing with hypothetic, minuscule, or just silly risks, this is when I have a problem. Unfortunately, much of today’s environmental movement relies on this.
Why? My guess is that the environment has gotten so much better (unleaded gas, catalytic converters, not dumping shit into rivers anymore…) that in a way, environmentalists have put themselves out of business. In order to keep going, they are focusing on silly stuff, like BPA on cash register receipts and other non-issues.

Much of the environmental movement is not focused on silly stuff, the so-called insignificantly dilute amounts of toxic substances which in theory should not affect us. One of the highly diluted components of the atmosphere, carbon dioxide, now makes up 0.04 % (400 ppm) of the atmosphere. That small and growing amount is leading to a fair amount of climate change with all sorts of serious repercussions for the present and future.(A few years ago Canada’s Fraser Institute circulated a brochure in schools arguing that  CO2 could not possibly be wreaking havoc due to its small percent in the atmosphere!) PM 2.5 pollution has not gone away, especially in China. They produce it partly because of their lax standards, which are tied in to our consumption of their “low-cost” goods. And finally–and I wish there only three areas of concern—I want to address the problem of eutrophication, the out-of-control growth of algae following the runoff of fertilizer (not entirely equivalent to Josh Bloom’s “dumping of shit” but significant nonetheless) into bodies of water like lake Erie.

No-till farming of soybeans near Lake Erie; invasive zebra and quaga mussels; intense growth of cattle and pig farms; altered wind direction and larger spring rainfall amounts(possibly linked to increased CO2 concentrations all played a role in concentrating the blue green algae and their toxins near Toledo, Ohio’s water treatment plant . (see Why Blooms Are Taking over Erie Again) Since present and past concentrations of microcystins have not yet been released by the municipality of Toledo, its residents still feel insecure about how close to and over the threshold their drinking water has come.

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mycrocystin

Cyanobacteria (blue green algae) thrive and some species produce toxic peptides known as microcystins . Blue-greens grow well with increased turbidity in the water caused by the bloom of other algae from elevated levels of phosphorous and nitrogen. They survive temperatures from 5 to 30 C range, preferring the upper range, and can tolerate pHs from 6 to 9.  Most blooms occur in late summer and early fall, but this one affecting Toledo was early in the season. The 65 known varieties of microcystins are released after algae cells die. Once making through city filtration systems, microcystins cannot be destroyed by boiling water, and they persist for weeks or months. (sources: EPA  and Health and Welfare Canada) The compounds attack the liver by being potent inhibitors of a pair of enzymes that transfer phosphate groups , and they are also skin, eye and throat irritants.

There is a World Health Organization drinking water guideline of 1 microgram per L(µg/L or 1 part in a billion) for microcystins. This was put in place partly because in 1996, 101 dialysis patients became ill and 50 died from liver failure in Brazil after microcystins contaminated the water in one specific reservoir. The substances can also be tumor promoters  The proposed guidelines for the US, Australia and Canada are in the 1 to 1.5 µg/L range. In laboratory animals, the amount of microcystins in the liver that is associated with acute hemorrhagicshock syndrome is approximately 60 to 70 µg/kg of body weight, a very small but deadly concentration.

BMAA(beta-Methylamino-L-alanine) is another toxin released by some blue-green algae, and it bioconcentrates in the food chain. A hypothesis regarding its link to neurodegenerative diseases has been under investigation and has not been dismissed so far.

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