Rotenone synergists

Botanicals Plant extracts without petroleum-based synergists (pyrethrum, rotenone, nicotine, neem, horsetail) Rare Rare... 

Currently pest control by natural plant extracts is practiced primarily by subsistence farmers in those less developed part of the world where it is still an economic necessity.(ref. 3). Of the approximately 2000 plant species with known insecticidal properties (ref. 4), few have been developed commercially. These include the pyrethrins, rotenones and some of the alkaloids. Pyrethrins were the most important natural plant extracts in the early commercial insecticide formulations and were already in use in Persia and Yugoslavia during the early 1800s. By 1939 pyrethrum imports to the United States were 13-5 million lbs, declining from this peak as the synthetic analogs (e.g., the allethrins) appeared on the market. The addition of stabilizers (antioxidants) and synergists to the original pyrethrum formulations saved the natural product from commercial extinction. Currently the demand for pyrethrum flowers is still over 25,000 tons per annum—met by hand-harvested crops from Ecuador, Kenya and Tanzania (ref. 5) ... 

In the antiproliferative effects of the MDR mouse lymphoma cells, a combination of flavonoids and epirubicin was studied. The interaction of chrysene or amorphigenin with epirubicin was synergistic and the interaction of rotenone with epirubicin was additive. On the MRP-carrying human breast cancer cells, formononetin and kaempferol revealed their good antiproliferative effects with synergistically epirubicin, whereas afrormosin and robinin had only an additive type of interaction. 

Examples of these include sesamin and sesamolin, both active principles of sesame oil, and piperonyl butoxide (PBO) and sesamex, both synthetic products. Although initially developed for use with pyrethrins, they have since been observed to synergize some, but not all, carbamates, organophosphates, pyrethroids, and organochlorines. In addition to the MDP compounds, another type of synergist called MGK 264 was developed to synergize the toxicity of pyrethroids and rotenone. The structure of piperonyl butoxide and MGK 264 are as follows ... 

Although this natural substance is present in a number of plants, the sonrce of most rotenone nsed in the United States is the dried derris root imported from Central and South America. It is formulated as dusts, powders, and sprays (less than 5% active ingredient) for use in gardens and on food crops. Many prodncts contain piperonyl butoxide as synergist, and other pesticides are inclnded in some commercial products. Rotenone degrades rapidly in the enviromnent. Emulsions of rotenone are applied to lakes and ponds to kill fish. 

Gao HM, Hong IS, Zhang W, Liu B (2003) Synergistic dopaminergic neurotoxicity of the pesticide rotenone and inflammogen hpo-polysaccharide Relevance to the etiology of Parkinson s disease. J Neurosci 23 1228-1236. 

Piperonyl butoxide is a synergist for carbamates, pyrethrins, pyrethroids, and rotenone. 

Use Synergist in insecticides in combination with rotenone, pyrethrins, or rotenone-pyrethrin mixture in oil solutions, emulsions, or powders. 

Toxicology LD50 (oral, rat) 2800 mg/kg, (skin, rabbit) 470 mg/kg mod. toxic by ing., skin contact, and IP routes large doses may cause CNS effects (excitation and depression) toxic by skin absorption causing CNS effects experimental reproductive effector Hazardous Decomp. Prods. CO2, CO, NOx Uses Synergist in insecticides to increase insecticidal effect of pyrethrins, pyrethroids (esp. allethrin), and rotenones usually used with piperonyl butoxide stabilizer in repellents for personal use... 

Pyrethrins Some formulations contain piperonyl butoxide (synergist), A-octyl bicycloheptene dicarboximide (synergist), di-n-propyl isocinchomeronate (repellent), permethrin, carbaryl, or rotenone. The marketed formulatirms are spray, foam, dust, shampoo (0.2%), dip, or ear drops, and the target parasites are mainly fleas, ticks, mites, and lice (some products). 

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