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Warm temperatures and fertilizer runoff fueled a large algae bloom throughout western Lake Erie over the past few days, turning water the color of pea soup. But the bloom wasn’t just unsightly–the dominant species, a type of blue-green algae called microcystis spp, produce a toxin that can harm humans. If ingested, the toxin can cause “numbness, nausea, dizziness, and vomiting and lead to liver damage,” according to the NASA Earth Observatory, and in rare cases can be deadly.
Testing of water supplies revealed toxins in the water supply of Toledo, so over the weekend, authorities ordered people not to drink the water, leaving about 500,000 to scramble for bottled drinking supplies. The order has since been lifted, as testing has revealed that levels of toxins have dipped to allegedly safe levels–although the results haven’t been released to the public. This may be because the bloom has slightly dissipated or because the water is not mixing enough to bring the usually top-dwelling algae down toward the lake bottom where Toledo’s water-intake pipes reside. But concerns remain, and it could get bad again, as algae blooms usually peak in August and September.
Some have likened the algae blooms to the past environmental woes of Lake Erie, such as when Cleveland’s main river–the Cuyahoga–went up in flames in 1969. But some fear that recent algae blooms are equally as bad, or even more concerning, because these toxins can have serious health effects, and algae blooms seem to get bigger by the year. “This is worse than the Cuyahoga River burning,” Carol Stepien, director of the University of Toledo’s Lake Erie Center, told USA Today.
The above image was taken by the Landsat 8 satellite on Aug. 1. The second image, below, was taken by NASA’s Aqua satellite on Aug. 3 and shows Toledo, Ohio and Maumee Bay on the lower left and Detroit at the top left on the shores of Lake St. Clair.
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