mi·​cro·​cys·​tin | \ ˌmī-krə-ˈsi-stin How to pronounce microcystin (audio) \

Definition of microcystin

: any of various toxins that are produced by freshwater cyanobacteria (genus Microcystis, especially M. aeruginosa), have hepatotoxic effects in animals including humans, and may occur in large quantities and contaminate water supplies during algal blooms (see bloom entry 2 sense 1d) … two water samples from a Toledo treatment plant tested positive for microcystin, a toxin possibly caused by an algae bloom in Lake Erie. Residents were told not to drink, or even boil, the water tainted with microcystin, which can cause nausea and impair liver function.— Lauren Raab When cyanobacteria die, they release microcystin, and scientists have found that remaining cyanobacteria respond to the molecule by making more of their own.— Carl Zimmer

Examples of microcystin in a Sentence

Recent Examples on the Web They are made up of cyanobacteria, also called blue-green algae, that can produce the toxin microcystin, potentially harmful to both humans and wildlife. Keith Matheny, Detroit Free Press, "Lake Erie algae bloom forecast improved, but states failing in war against nutrient loads," 9 July 2020 Some 500,000 people in and around Toledo had their water supplies disrupted for a weekend in August 2014 because of high levels of microcystin-producing algae in western Lake Erie, near the city's water intakes. Keith Matheny, Detroit Free Press, "Lake Erie algae bloom forecast improved, but states failing in war against nutrient loads," 9 July 2020 But this was the only time the toxic microcystin bacteria entered the water pipes to people’s homes. Mary Kilpatrick, cleveland, "2014, the year Cleveland lost Tamir Rice: Biggest stories of the 2010s," 21 Dec. 2019 Since then, water treatment plants have been updated to detect and treat microcystin to keep drinking water safe. Laura Johnston, cleveland.com, "Scientists to test water samples across Lake Erie for annual HABs grab," 7 Aug. 2019 None contained microcystins, a dangerous cyanotoxin, according to a Monday update. Molly Harbarger, OregonLive.com, "Wilsonville water safe to drink after found free of cyanotoxins," 4 June 2018 When the cyanobacteria die off, the toxin microcystin is produced. Megan Becka, cleveland.com, "Health advisory issued for harmful algal bloom in Springfield Lake near Akron," 26 July 2019 Algae doesn’t always pose a health or environmental risk, but cyanobacteria can produce a toxin called microcystin that, if consumed, can damage the liver and irritate the skin, eyes and throat, according to the U.S. Environmental Protection Agency. Maya Sweedler, WSJ, "Florida Fights Giant Algal Bloom in Lake Okeechobee," 16 July 2018 As the weather warmed, the bloom grew and developed toxins — specifically, the cyanotoxins known as cylindrospermopsin and microcystin. Everton Bailey Jr., OregonLive.com, "1 dead, several injured in 3-car crash near Woodburn," 7 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'microcystin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of microcystin

1965, in the meaning defined above

History and Etymology for microcystin

New Latin Microcystis, a species of cyanobacteria (from micro- micro- + Greek kýstis "pouch, bladder") + -in entry 1 — more at cyst

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The first known use of microcystin was in 1965

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Cite this Entry

“Microcystin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microcystin. Accessed 5 Mar. 2021.

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