chlorpyrifos

noun
chlor·​pyr·​i·​fos | \ klȯr-ˈpir-ə-fäs How to pronounce chlorpyrifos (audio) , -ˈpī-rə \

Definition of chlorpyrifos

: a toxic crystalline organophosphate pesticide C9H11Cl3NO3PS that inhibits acetylcholinesterase and is used to control insect pests and ticks

Examples of chlorpyrifos in a Sentence

Recent Examples on the Web Ultimately a federal appeals court ordered the E.P.A. to issue a final ruling on whether to ban chlorpyrifos by July 2019. Lisa Friedman, New York Times, "E.P.A. Rejects Its Own Findings That a Pesticide Harms Children’s Brains," 23 Sep. 2020 After ratcheting up restrictions on application of chlorpyrifos products over the past last several years, the state opted this year to revoke product registrations — effectively a ban. Geoffrey Mohan, Los Angeles Times, "Chemical companies agree to end fight over pesticide ban," 9 Oct. 2019 Apple farmers have argued that chlorpyrifos is the only pesticide available for use against pests such as the rosy apple aphid. USA TODAY, "Duck seeking duck, forest ornaments, Alice Cooper’s Christmas Pudding: News from around our 50 states," 13 Dec. 2019 Scientists say studies have shown that chlorpyrifos damages the brains of fetuses and children. Washington Post, "EPA rejects challenge of pesticide linked to brain damage," 18 July 2019 There are already signs that most farmers realize their era of using chlorpyrifos is nearly over. Thomas D. Elias, The Mercury News, "Opinion: The end in sight for a perilous pesticide in California," 3 Sep. 2019 Environmental groups have since pushed Cuomo to act to ban the pesticide, chlorpyrifos, used on golf courses and crops including corn, soybeans and broccoli. USA TODAY, "Duck seeking duck, forest ornaments, Alice Cooper’s Christmas Pudding: News from around our 50 states," 13 Dec. 2019 California and several other states have prohibited chlorpyrifos within their boundaries. Bob Egelko, SFChronicle.com, "California to Trump: See you in court, with a barrage of lawsuits," 18 Aug. 2019 In 2016, more than 640,000 acres were treated with chlorpyrifos in California alone. Lisa Friedman, New York Times, "E.P.A. Won’t Ban Chlorpyrifos, Pesticide Tied to Children’s Health Problems," 18 July 2019

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

1970, in the meaning defined above

History and Etymology for chlorpyrifos

chlor- + pyridine + -fos (alteration of phosphorus)

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Time Traveler for chlorpyrifos

Time Traveler

The first known use of chlorpyrifos was in 1970

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Statistics for chlorpyrifos

Last Updated

29 Sep 2020

Cite this Entry

“Chlorpyrifos.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/chlorpyrifos. Accessed 24 Oct. 2020.

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More Definitions for chlorpyrifos

chlorpyrifos

noun
chlor·​pyr·​i·​fos | \ -ˈpir-ə-fäs, -ˈpī-rə- How to pronounce chlorpyrifos (audio) \

Medical Definition of chlorpyrifos

: a toxic crystalline organophosphate pesticide C9H11Cl3NO3PS that inhibits acetylcholinesterase and is used to control insect pests and ticks

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