Insecticides rotenone

To Muller, just starting out on his search for an effective insecticide, the situation looked desperate indeed. A flood of patents had already been issued, and he realized that the chances were worse than poor only a particularly cheap or remarkably effective insecticide had any prospects of being used in agriculture. Yet there was hope. After experimenting with products described in the patent literature, he realized that practically none of the new compounds was being sold the existing arsenates, pyrethrum, and rotenone insecticides were more effective. Reassured about the competition, Muller had the courage to press on. 

Rotenone (32) is known as potent insecticide, with reduced toxicity to mammals the oral acute LD50 in rats is 60 mg/kg, while intravenous and intraperitoneal LD50 values are 0.2 mg/kg and 1.6 mg/kg respectively [62]. Chronic studies indicated that the no observed effect level (NOEL) determined in rats in a 24-month exposure was 7.5 mg/kg of diet [114]. Results of this study and other previously reported suggest that even unusually high treatment rates of rotenone do not cause tumors or reproductive problems in humans [114]. Rotenone insecticide action is due to its ability to block oxidative phosphorylation in the mitochondria [62]. Selective toxicity to insects and not to mammals results from the existing differences in the inability of insects to further metabolize toxic rotenolones biodegradation products [63]. 

Rotenoids. The use of rotenone-bearing roots as insecticides in the United States was developed as a result of federal laws against residues of lead, arsenic, and fluorine upon edible produce. Rotenone [83-79-4] (5) is harmless to plants, highly toxic to many insects, and relatively innocuous to... 

Rotenone is a common insecticide that strongly inhibits the NADH-UQ reductase. Rotenone is obtained from the roots of several species of plants. Tribes in certain parts of the world have made a practice of beating the roots of trees along riverbanks to release rotenone into the water, where it paralyzes fish and makes them easy prey. Ptericidin, Amytal, and other barbiturates, mercurial... 

Rotenone is a complex flavonoid found in the plant Derris ellyptica. It acts by inhibiting electron transport in the mitochondrion. Derris powder is an insecticidal preparation made from the plant, which is highly toxic to hsh. 

Rotenone A complex flavonoid produced by the plant Denis ellyptica. It has insecticidal activity due to its ability to inhibit electron transport in the mitochondrion. 

Synthetic organics dominate the field of new insecticides. Much time and money have been spent in attempting to determine the chemical structures of rotenone, pyre-thrum, and other natural insecticides, and to reconstruct them through synthesis. A great deal has been learned about the chemical structures of these compounds, but little success has been attained toward synthesis. Nicotine and, recently, a pyrethrumlike compound are exceptions, but the synthesis of nicotine is too expensive to be practical. The basic information obtained has possibly been helpful in directing the thoughts of the chemist to the synthesis of entirely new compounds. 

After mothproofing wool, the next logical step for Geigy was to invent an insecticide that killed more kinds of pests. Imported natural insecticides made from plants, including pyrethrum from tropical chrysanthemums, rotenone from a tropical vine, and nicotine from tobacco, could be quite expensive they were also not persistent and were easily destroyed by light and heat. American and European attempts to synthesize their active ingredients had failed. Arsenic compounds remained the only cheap and effective insecticides. 

For four years, Muller synthesized his own compounds and almost single-handedly screened them for their effect on houseflies. They were known to be transmitters of intestinal diseases like dysentery, and it was speculated at the time that they might spread polio. Muller built a cubic-meter glass chamber for insects and sprayed compound after compound at them. As soon as one compound seemed promising, he searched more carefully among its close relatives, using the natural insecticides, rotenone and pyrethrum, as controls. 

At first, Geigy s biologists were puzzled because the insects sprayed with DDT did not die immediately. Accustomed to the quick action of pyrethrum and rotenone, they dismissed Muller s discovery as unimportant. They did not realize that DDT s long period of activity could be far more important than sheer speed. In the parlance of insecticides, DDT had slow knockdown but sure kill. Surfaces sprayed with DDT in 1941 and stored under dust-free laboratory conditions were still toxic to insects seven years later. 

Andreas Buxtorf and Max Spindler. Fifteen Years of Geigy Pest Control. Basel, Switzerland J. R. Geigy S.A., 1954. Source for Geigy woolen specialty natural insecticides delousing during World War I pre-DDT insecticides pyrethrum and rotenone as controls and visit to United States. 

Rotenone No longer approved Caterpillar, beetles, aphids Potato, apple Insecticide... 

There have also been reports of neoplasms in native bottomfeeding fish with a suggestion that carcinogenic hydrocarbons from motor boat exhausts, rotenone and insecticides such as DDT may be involved as causative agents (59.). Similarly (an) unidentified carcinogen(s) are suspected in the case of adematous polyps of gastric mucosa of fish, reported recently (60). The diet of these fish was free of aflatoxins. 

Ivie, G.W. and Casida, J.E. Enhancement of photoalteration of cyclodiene insecticide chemical residues by rotenone. Science (Washington, DC), 167(3935) 1620-1622, 1970. 

Guadano A, Gonzaalez-Coloma A, de la Pena E Genotoxicity of the insecticide rotenone in cultured human lymphocytes. Mutat Res 414(l-3) l-7, 1998... 

Early insecticides also included organic natural products such as nicotine, rotenone, and pyrethrin. Rotenone is used today as a method of killing rough fish when a lake has been taken over completely by them. A couple of weeks after treatment the lake is then planted with fresh game fish. The... 

Rotenone and the rotenoids (Figure 2) have long been used as Insecticides and plscicides (fish poisons). By the early 1950 s more than 7 million pounds of Legumlnosae roots (Perris, Lonchocarpus, and Tephrosia spp.) containing these insecticides were imported annually into the United States. In 1972, about 1.5 million pounds of the roots were used in the United States for pest control in the home and garden markets and to control ectoparasites on animals (10). 

Figure 2. Structure of Rotenone, an Insecticide and Piscicide Isolated from Leguminosae Roots...

A remarkable number of insecticidal plants seem to have been recognized first as fish poisons. This group has received special scientific attention for example, the already mentioned rotenone and other rotenoids of Perris and Lonchocarpus species (3-6), the lupine alkaloids of Sophora species (13), and a saponin (medicagenic acid) from Medlcago sativa leaves ( ). 

Plants have provided several other important pesticides. The group of insecticides called pyrethrums was harvested and refined from chrysanthemums. The plant nux vomica contains strychnine, which was used to kill rodents. Rotenone, another important insecticide was extracted from the root of Denis eliptica. Plant extracts were useful, but difficult to purify and obtain in quantity. Significant increases in the use of pesticides occurred with advances in synthetic chemistry and our understanding of biology. 

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