pyrethrin

plural pyrethrins

1. chemistryAny of a number of naturally occurring insecticides extracted from the pyrethrum plant; unusual in having a cyclopropane ring.

   *Permethrin is the artificial version of pyrethrin, which is made from chrysanthemum flowers.

   2023, translated in 2025, Berta Páramo and translated by Marc Correa Haro, Lice: How to Survive on Humans, page 152

   2 more examples

   Ecoparasite control, with appropriate concentrations of carbaryl, malathion, or pyrethrin dusts, is permissible if the agent is applied externally to both test and control animals not less than seven days prior to the start of the test.

   1983, D. E. Kaukeinen, Vertebrate Pest Control and Management Materials, page 102

   The biggest risk raised in the findings, Mr. Abecassis said, is the exposure to pesticides, which have been linked to a range of serious illnesses including fatal cancers and organ damage. Six of the tested products contained chemicals like myclobutanil and pyrethrins in concentrations far above state limits, according to the analysis.

   2022 December 1, Ashley Southall, “What’s in New York’s Illicit Cannabis: Germs, Toxins and Metals”, in The New York Times