Methoprene is a pesticide that acts as a juvenile hormone agonist. Although developed initially against insects, it has since been shown to have toxic effects on larval and adult crustaceans. Methoprene was one of the several pesticides applied to the Western Long Island Sound (WLIS) watershed area during the summer of 1999. Methoprene is a racemic mixture of two enantiomers (R and S in a ratio of 1:1). The activity of the compound as a juvenile hormone is restricted to the S enantiomer. Recent data have been describing the male sexual enhancement after methoprene treatment in Anastrepha fraterculus (Diptera: Tephritidae). It has been shown, that a sustained response doesn`t not fade away after sexual maturation, thus the potential benefits of using methoprene to increase the efficiency of the sterile insect technique, which is an environmentally safe method to control this fruit pest, have been proposed.

(E)-Tetrachlorovinphos is an (E)- isomer of Tetrachlorovinphos. Tetrachlorovinphos is an organophosphate cholinesterase inhibitor that is used as an insecticide. Tetrachlorvinphos was introduced and first used commercially in 1966 in the USA. Tetrachlorvinphos was originally registered for use on various food crops, livestock, pet animals. Tetrachlorvinphos is applied dermally to livestock to control flies and mites. It is used as an oral larvicide in cattle, hog, goats and horses; in cattle ear tags to control flies; in cattle feedlots; in poultry dust boxes to control poultry mites; and in poultry houses. Tetrachlorvinphos also is used in pet sleeping areas and pet flea collars and to control flies around refuse sites, recreational areas, and for general outdoor treatment. Tetrachlorvinphos can cause cholinesterase inhibition in humans; that is, it can overstimulate the nervous system causing nausea, dizziness, confusion, and at very high exposures (e.g., accidents or major spills), respiratory paralysis and death. In 2014, the Natural Resources Defense Council (NRDC) filed a lawsuit against the United States Environmental Protection Agency (EPA) seeking EPA to respond to NRDC’s 2009 petition to ban tetrachlorvinphos in common pet flea treatment products. Tetrachlorvinphos is reportedly registered for use in Canada, South Africa, and Australia.

Chlorpyrifos-methyl is a broad-spectrum organophosphorous insecticide and potential toxic pollutant widely used in agriculture and effective against a wide range of insect pests in commercial importance crops. Chlorpyrifos-methyl have endocrine disruption activity, especially anti-androgenic effects and Chlorpyrifos-methyl administration leads to hepatotoxicity and neurotoxicity in mammals. The fish exposed to chlorpyrifos-methyl exhibited behavioral changes in the form of neurotoxin toxicity: less general activity than control group, loss of equilibrium, erratic swimming and staying motionless at a certain location

Azamethiphos, an organothiophosphate insecticide, initially was used in 1991 for the treatment against sea lice. However, because of reduced sensitivity in 1999, the use of this compound was terminated. Azamethiphos was re-introduced in 2008; it’s the main component of Salmosan, a pesticide presently used for treatment against sea lice. Salmosan is applied as a bath treatment and then released into the surrounding seawater

Fenvalerate is type II pyrethroid and widely used pesticide. Fenvalerate is listed under Class IV of the U.S. Food and Drug Administration (USFDA) Surveillance Index Classification, indicating a low hazard potential to humans from both exposure and toxicological standpoints. Fenvalerate irreversibly prolongs the sodium current during depolarization. The sensitization of sodium channels, probably tetrodotoxin-resistant (TTX-R) sodium channels, by the long-term activation of protein kinase C may play an important role in the enhancement of the duration of fenvalerate-induced nociceptive behavior in diabetic mice. Fenvalerate inhibits testosterone synthesis via pathways involving intracellular Ca(2+) and circadian clock genes (Bmal1, Rev-Erb alpha, Ror alpha) as well as StAR mRNA expression in TM3 cells. It potently inhibits human CYP2D6 and moderately CYP3A4. Fenvalerate has an anxiolytic effect on rats.