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Warning Signs of a Harmful Algal Bloom
Before Getting Into The Water
In general, just looking at a water body will not tell you if there are cyanotoxins present in the water. The pictures about are examples of extreme cases, but as little as 0.3 micrograms per liter of microcystins for children under 6 or 1.6 micrograms per liter healthy adults have been proven dangerous for consumption according to the EPA. There are no current regulations for anatoxin-a, but studies have show that it contains a LD50, that is the lethal dose for 50 percent of test subjects, is 13.3 milligrams per kilogram. Before getting into the water or letting pets near, check for bad smelling water, or foam or scum with green, blue, brown, or reddish colors as these are signs of cyanobacteria. Water may take on a weird taste as well. Check with local advisories and don’t hesitate to report any of these signs if no advisories are already up.
If you think you may have been exposed to cyanobacteria, it is suggested to rinse off with clean water as soon as possible. General warming symptoms of cyanobacteria, maybe a small as allergic reactions like skin rashes, and fever to gastrointestinal issues like vomiting and diarrhea. Long terms effects my be liver and kidney damage. There are similar symptoms in pets as well. Contact poison control and seek medical attention if you experience these symptoms and think you have been exposed.
Equipment Used to Test for Cyanobacteria
There are a few pieces of equipment that test for cyanobacteria, but the most common are ELISA, enzyme linked immunosorbent assays, and LC/MS/MS, liquid chromatography tandem mass spectrometry. Both have their problems, ELISA having lower sensitivity and LC/MS/MS being long and expensive but they also have their advantages that make them great assets.
Carpenter, Kurt. Algal bloom in the Ross Island Lagoon, Willamette River, Oregon [Image File]. In Harmful Algal Blooms and Drinking Water in Oregon. https://www.usgs.gov/centers/or-water/science/harmful-algal-blooms-and-drinking-water-oregon?qt-science_center_objects=0#qt-science_center_objects
St. Amand, Ann. Figure 2. Cyanobacteria, Microcystic aeruginosa [Image File]. In Field and Laboratory Guide to Freshwater Cyanobacteria harmful Algal Blooms for Native American and Alaska Native Communities. https://pubs.er.usgs.gov/publication/ofr20151164
St. Amand, Ann. Figure 3. Cyanobacteria, Microcystic aeruginosa [Image File]. In Field and Laboratory Guide to Freshwater Cyanobacteria harmful Algal Blooms for Native American and Alaska Native Communities. https://pubs.er.usgs.gov/publication/ofr20151164
Water Research Foundation. Understanding Cyanobacteria and Cyanotoxins [Video File}. Youtube, August 24, 2016. https://www.youtube.com/watch?v=S9iyKdHt5_c
United States Environmental Protection Agency. Health Effects from Cyanotoxins. https://www.epa.gov/cyanohabs/health-effects-cyanotoxins