mi·​cro·​gram | \ ˈmī-krə-ˌgram \

Definition of microgram

: one millionth of a gram — see Metric System Table

Examples of microgram in a Sentence

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For instance, tests at the district’s Academy of the Americas Elementary school found a kitchen and drinking faucet in a basement cafeteria that had lead levels of 182 micrograms per liter (ug/L) and 154 ug/L, respectively. Beth Mole, Ars Technica, "Lead in US school water “disturbing”—Detroit just shut off all fountains," 31 Aug. 2018 All women of reproductive age — but especially Hispanic women — should eat only fortified corn products and take daily supplements that contain 400 micrograms of folic acid, the researchers said. Jonel Aleccia, The Seattle Times, "FDA allows food makers to fortify corn masa to halt birth defects, but few do," 16 Oct. 2018 Of those, only 19 contained toxin levels greater than 10 micrograms per liter, the level the World Health Organization considers a low-level risk. Maya Sweedler, WSJ, "Florida Fights Giant Algal Bloom in Lake Okeechobee," 16 July 2018 For instance, over time, getting more than 10,000 micrograms a day of vitamin A can cause headaches, diarrhea, liver damage, and bone thinning, the Mayo Clinic notes. Cassie Shortsleeve, SELF, "Do I Really Need to Take Prenatal Vitamins Before I’m Even Pregnant?," 19 Apr. 2018 Because there is no safe level of lead, even those children whose lead levels are below the official threshold — set at 5 micrograms per deciliter of blood — may see health impacts down the line. For Thornton, that concern is highly personal. Molly Rauch, Good Housekeeping, "When Your Water Poisons Your Children," 16 Feb. 2016 And the mean amount of lead in their blood samples also dropped — from 2.33 micrograms per deciliter in 2006 to 1.15 in 2016. Kristen Jordan Shamus, Detroit Free Press, "Study: Flint children's blood lead levels hit historic low in 2016," 26 Mar. 2018 All tests came back positive for lead, at 12, 17, and 23 micrograms per deciliter. Deborah Bloom, CNN, "The woman risking her life to save a village from lead poisoning," 20 Apr. 2018 The annual average of PM 2.5 levels for Sacramento County from 2016, the most recent year available, shows 8.8 micrograms per cubic meter, according to kidsdata.org. Hannah Holzer, sacbee, "Air pollution increases risk for type 2 diabetes, study finds," 12 July 2018

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

circa 1890, in the meaning defined above

History and Etymology for microgram

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Statistics for microgram

Last Updated

9 Dec 2018

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Time Traveler for microgram

The first known use of microgram was circa 1890

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More Definitions for microgram


mi·​cro·​gram | \ ˈmī-krə-ˌgram \

Medical Definition of microgram

1 : one millionth of a gram

More from Merriam-Webster on microgram

Britannica.com: Encyclopedia article about microgram

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