Improved understanding of the factors determining the insecticidal activity, the mammalian toxicity, and the stability in air and light of natural and synthetic pyrethroids has led to a series of new compounds with a very favorable combination of properties. Their characteristics include outstanding potency to insects, low toxicity to mammals associated with rapid metabolic breakdown and, in ap...

In this review we have examined the status of parameters required by pyrethroid QSAR-PBPK/PD models for assessing health risks. In lieu of the chemical,biological, biochemical, and toxicological information developed on the pyrethroids since 1968, the finding of suitable parameters for QSAR and PBPK/PD model development was a monumental task. The most useful information obtained came from rat t...

BACKGROUND Mosquito strains that exhibit increased tolerance to the chemical class of compounds with a sodium channel modulator mode of action (pyrethroids and pyrethrins) are typically described as "pyrethroid resistant". Resistance to pyrethroids is an increasingly important challenge in the control of mosquito-borne diseases, such as malaria or dengue, because one of the main interventions (...

Synthetic pyrethroids are present in numerous commercial insecticide formulations and have extensive indoor and outdoor applications worldwide, including agricultural, public, residential, and veterinary usages for pest control. Pyrethroid use has increased continuously in recent years. The aim of this review is to provide updated and comprehensive information on human exposure and potential ha...

The Cytogenetic effects of Cypermethrin a synthetic pyrithroid insecticide was investigated on human lymphocytes cultured in-vitro. Utilizing the trypan blue dye exclusion technique assay the LC50 of cypermethrin was found to be 36 uM. Based on LC50 value, cypermethrin was found to be low toxic to lymphocyte culture. Cypermethrin showed an increase in the frequency of chromosomal aberrations an...

The influence of post-treatment temperature on the toxicities of two pyrethroids (lambda-cyhalothrin and bifenthrin), a carbamate (methomyl) and a spinosyn (spinosad) to Ostrinia nubilalis (Hubner) larvae was evaluated in laboratory assays. From 24 to 35 degrees C, the toxicities of the pyrethroids decreased 9.5- and 13.6-fold while spinosad toxicity decreased 3.8-fold. The toxicity of methomyl...

Insecticides continue to be the primary means of control for ectoparasites on livestock. Intensive use of these materials has led to resistance to organochlorines, organophosphates and pyrethroids among populations of Haematobia irritans irritans, H. irritans exigua and Lucilia cuprina. Similarly, use of acaricides has led to resistance in one-host Boophilus ticks to all currently-used organoph...

Three synthetic pyrethroids were tested for their efficacy against two populations of the filariasis vector Culex quinquefasciatus under laboratory conditions following the WHO procedure, Emulsifiable concentration and technical grade formulations of deltamethrin (2.5% wp), cypermethrin (1.0% EC) and permethrin (25% EC) were employed on the larvae of the said species collected from Mysore and M...

Development of pyrethroids for household use and recent advances in the syntheses of (1R)-trans-chrysanthemic acid, the acid moiety of most of the household pyrethroids, are reviewed. As another important acid moiety, we discovered norchrysanthemic acid to have a significant vapor action at room temperature when esterified with fluorobenzyl alcohols. In particular, 2,3,5,6-tetrafluoro-4-methoxy...