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

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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.

First Known Use of methylmercury

1915, in the meaning defined above

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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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