meth·​yl·​mer·​cury | \ ˌme-thəl-ˈmər-kyə-rē How to pronounce methylmercury (audio) , -ˈmər-k(ə-)rē\

Definition of methylmercury

: any of various toxic compounds of mercury containing the complex CH3Hg− that often occur as pollutants which accumulate in living organisms (such as fish) especially in higher levels of a food chain

Examples of methylmercury in a Sentence

Recent Examples on the Web Face creams often contain mercury salts, but the woman’s toiletry item contained much stronger methylmercury iodide. Los Angeles Times, "Woman hospitalized with mercury poisoning after using face cream from Mexico," 13 Sep. 2019 The importer apparently added methylmercury into the cream, according to the Sacramento County Department of Health Services in a statement released Tuesday. Joshua Bote, USA TODAY, "Woman in coma after using face cream tainted with mercury, officials say," 12 Sep. 2019 Mercury is a naturally occurring metal that is released into the environment from mining and burning coal, which can accumulate in fish in a more toxic form of methylmercury, the office’s report said. Joseph Geha, The Mercury News, "New safety guidelines issued for eating fish from Coyote Lake," 13 Aug. 2019 After decades of water sampling on Little Rock Lake and two other nearby lakes, Watras concluded that climate change is causing fluctuations in the level of dangerous methylmercury in the environment. Milwaukee Journal Sentinel, "Wisconsin has cut mercury pollution of its lakes. Climate change puts those gains at risk.," 14 June 2019 The potential negative effects of methylmercury in fish are far smaller than the adverse effects of eating too little fish. Jaclyn London, Ms, Rd, Good Housekeeping, "Why Salmon Needs to Become a Part of Your Diet ASAP," 27 Mar. 2018 Once that mercury is dumped into a river, however, naturally occurring bacteria turn it into methylmercury, a powerful neurotoxin that can wreak havoc on the nervous system, particularly in developing infants. Jim Wyss, miamiherald, "How U.S. demand for gold jewelry and bullion is poisoning children in the Amazon," 26 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'methylmercury.' 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 methylmercury

1915, in the meaning defined above

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Statistics for methylmercury

Last Updated

23 Oct 2019

Time Traveler for methylmercury

The first known use of methylmercury was in 1915

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More Definitions for methylmercury


meth·​yl·​mer·​cury | \ ˌmeth-əl-ˈmər-kyə-rē, British also ˌmē-ˌthīl-\
plural methylmercuries

Medical Definition of methylmercury

: any of various toxic compounds of mercury containing the complex CH3Hg− that often occur as pollutants formed as industrial by-products or pesticide residues, tend to accumulate in living organisms (as fish) especially in higher levels of a food chain, are rapidly and easily absorbed through the human intestinal wall, and cause neurological dysfunction in humans — see minamata disease

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