tri·​halo·​meth·​ane | \ (ˌ)trī-ˌha-lə-ˈme-ˌthān How to pronounce trihalomethane (audio) , British usually -ˈmē- \

Definition of trihalomethane

: any of various derivatives CHX3 of methane (such as chloroform) that have three halogen atoms per molecule and are formed especially during the chlorination of drinking water

Examples of trihalomethane in a Sentence

Recent Examples on the Web The bureau advises us to filter our tap water because of carcinogenic chloramines and trihalomethane that are in the water as part of the disinfection process, as well as heavy metals that are picked up in the pipes on the way to homes. oregonlive, "Portland Commissioner Position 2 candidates explain what city policy changes they’ll immediately support if elected," 25 Apr. 2020 The water was verified to have high levels of TTHM, total trihalomethanes, which can cause multiple medical complications if consumed in large amounts. Detroit Free Press, "Health and race disparities in America have deep roots: A brief timeline," 20 Apr. 2020 Multiple municipal tests over the years show water in Martin County exceeds the maximum contaminant level for trihalomethane and haloacetic acid, both byproducts of the water’s treatment and both carcinogenic. April Johnston,, "‘That's vinegar’: The Ohio River’s history of contamination and progress made," 26 Dec. 2019 But Veolia has said it was only hired by the city to assess bacteria and harmful chlorine compounds (trihalomethanes) in Flint’s water supply, not lead. Wired, "Utility Executives Kept Flint's Tainted Water a Secret," 13 Dec. 2019 In Dos Palos, where the water contains potentially harmful chemicals known as trihalomethanes, Joaquin Garcia has 5-gallon jugs of clean water delivered to his home. Dale Kasler, Phillip Reese And Ryan Sabalow, sacbee, "360,000 Californians have unsafe drinking water. Are you one of them?," 1 June 2018 And not only lead, but trihalomethane (TTHM) – a chemical byproduct of chlorine disinfectant. Richard Horan, The Christian Science Monitor, "'The Poisoned City' tells the horrific story of Flint's contaminated water," 10 July 2018 Until several months ago, customers received notices on the back of their water bills stating that their water had been tested and found to be above federal limits of trihalomethanes and haloacetic acids. Nadia Kounang, CNN, "The Kentucky county where the water smells like diesel," 30 Mar. 2018 The quality of the city’s drinking water has been a hot-button issue since routine testing in Nov. 2016 revealed elevated levels of trihalomethane, a disinfectant by-product. Brian Ballou,, "Castillo re-elected in Pines, Monroig out," 12 Mar. 2018

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

1968, in the meaning defined above

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The first known use of trihalomethane was in 1968

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Cite this Entry

“Trihalomethane.” Dictionary, Merriam-Webster, Accessed 2 Mar. 2021.

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More Definitions for trihalomethane


tri·​halo·​meth·​ane | \ (ˌ)trī-ˌhā-lə-ˈmeth-ˌān, British usually -ˈmē-ˌthān \

Medical Definition of trihalomethane

: any of various derivatives CHX3 of methane (as chloroform) that have three halogen atoms per molecule and are formed especially during the chlorination of drinking water abbreviation THM

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