Also found in: Dictionary, Medical.



synthetic esters of chrysanthemumic acid; analogs of pyrethrins.

Pyrethroids are obtained either by the reaction of chrysanthemumyl chloride with an alcoholic moiety in the presence of a tertiary amine or by transesterification of the ethyl ester of chrysanthemumic acid in the presence of sodium. The pyrethroids that are most toxic to insects are esters of cyclopentenolones, of substituted benzyl alcohols, and of N-hydroxymethylimides.

Pyrethroids produced today include allethrin (2-allyl-3-meth-yl-2-cyclopenten-4-oI-l-onyl chrysanthemumate), furethrin (2-furfury 1 -3-methyl -2- cyclopenten - 4 -ol -1 - ony 1 chrysanthemum-ate), cyclethrin (2-cyclopentenyl-3-methyl-2-cyclopenten-4-ol-1 -onyl chrysanthemumate), barthrin (6-chloropiperonyl chrysanthemumate), dimethrin (2,4-dimethylbenzyl chrysanthemumate), and tetrametrine [N-(3,4,5,6-tetrahydrophthalimido)-methyl chrysanthemumate]. These compounds, usually in the form of aerosols, are used against household insects.


Mel’nikov, N. N., and K. D. Shvetsova-Shilovskaia. “Sintez insektitsidov piretrinovogo riada.” Khimicheskaia promyshlennost’, 1955, no. 3, pp. 50–61.
Volkov, Iu. P., and N. F. Shugal. “Sinteticheskie analogi piretrinov. Khimicheskaia promyshlennost’, 1969, no. 9, pp. 14–19.
Chemie der Pflanzenschutz- und Schädlingsbekä mpfungsmittel, vol. 1. Edited by R. Wegler. Berlin, 1970. Pages 87–102.


References in periodicals archive ?
This innovation allows analysis to be completed in less than two hours, and is able to detect pyrethroids at a concentration level of as low as 0.
The fast-acting, repellent toxicants include Bifenthrin and other pyrethroids that act as barriers to termite movement, while non-repellent, slower-acting compounds include Fipronil, Imidacloprid and Thiamethoxam, which are now among the preferred soil treatments (Wiltz, 2012).
In addition, a recent study in deltamethrin-resistant mosquitoes showed that sublethal doses of pyrethroids can interfere with parasite development (35).
Synthetic pyrethroids are new class of insecticides (Kumar, 2012) which are being used since 1970s.
Laboratory and field tests showed that the sampler accurately detected free concentrations of pyrethroids at concentrations as low as 1 part per trillion.
We found the sam pyrethroids in the breeding sites as in th fields, and we concluded that these small doss in the water are the source of resistance slection in this area," says Aristide Hien, an ntomologist who recently compared pesticid contamination and resistance levels in sectins of Dano growing conventional verss organic cotton.
Vector resistance to pyrethroids has been reported in African continent (28-33) and China (34).
Other pyrethroid and organophosphates have also been trialled.
The objective of this study was to evaluate this new bioassay technique and determine baseline susceptibility to a number of commonly used pyrethroid and organophosphate insecticides in 2 sand fly species, P papatasi and P duboscqi (Neveu-Lemaire), which are relevant to US military operations in the Middle East and Africa.
An increase in the urinary levels of two pyrethroid metabolites (3-PBA and cis-DBCA) in children is associated with a significant decrease in their cognitive performances , particularly verbal comprehension and working memory.
SAN DIEGO -- Exposure to common household pesticides called pyrethroids almost tripled the odds of attention-deficit/hyperactivity disorder in boys, but not in girls, authors of a large cross-sectional study reported.
The most common first-line treatments are the topical pediculicides, including the pyrethroids (available over the counter), malathion, benzyl alcohol, spinosad, and topical ivermectin.