A few years ago Toledo, Ohio, which lies on the shores of Lake Erie, had to issue a water alert because of a worrisome algal bloom. Residents were warned not to drink or bathe using city water and were told that boiling the water would intensify the toxicity. The panic spread 90 miles east to where I live and we made a run for Costco and its bottled-water aisle just to be on the safe side.
I remember thinking it was odd to get so worked up over pond scum. Growing up near water you’re used to seeing it on the shores and you just avoid it and move on. During that water-alert period I learned that cyanobacteria — also known as blue-green algae —can blossom into a harmful algal bloom capable of releasing all sorts of deadly poisons into the environment.
In the latest Speaking of Chemistry, produced by the American Chemical Society, the short video goes into great detail on the causes and dangers of the blooms. They even cited the Toledo incident. Check it out, it’s pretty fascinating.