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The information in this profile may be out-of-date. It was last revised in 1996. EXTOXNET no longer updates this information, but it may be useful as a reference or resource.

Please visit the National Pesticide Information Center (NPIC) to find updated pesticide fact sheets. If you don't find a fact sheet related to your question, feel free to call 1-800-858-7378. NPIC is open five days a week from 8:00am to 12:00pm Pacific Time.

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E X T O X N E T

Extension Toxicology Network

Pesticide Information Profiles

A Pesticide Information Project of Cooperative Extension Offices of Cornell University, Oregon State University, the University of Idaho, and the University of California at Davis and the Institute for Environmental Toxicology, Michigan State University. Major support and funding was provided by the USDA/Extension Service/National Agricultural Pesticide Impact Assessment Program.

EXTOXNET primary files maintained and archived at Oregon State University

Revised June 1996

Rotenone

Trade and Other Names: Trade names for products containing rotenone include Chem-Fish, Cuberol, Fish Tox, Noxfire, Rotacide, Sinid and Tox-R. It is also marketed as Curex Flea Duster, Derrin, Cenol Garden Dust, Chem-Mite, Cibe Extract and Green Cross Warble Powder. The compound may be used in formulations with other pesticides such as carbaryl, lindane, thiram, piperonyl butoxide, pyrethrins and quassia.

Regulatory Status: Rotenone is a General Use Pesticide (GUP), but uses on cranberries and for fish control are restricted uses. It is EPA toxicity class I or III - highly toxic or slightly toxic, depending on formulation. Rotenone, when formulated as an emulsified concentrate, is highly toxic and carries the Signal Word DANGER on its label. Other forms are slightly toxic and require the Signal Word CAUTION instead.

Chemical Class: Not Available

Introduction: Rotenone is a selective, non-specific botanical insecticide with some acaricidal properties. Rotenone is used in home gardens for insect control, for lice and tick control on pets, and for fish eradications as part of water body management. Rotenone is a rotenoid plant extract obtained from such species as barbasco, cub, haiari, nekoe, and timbo. These plants are members of the pea (Leguminosae) family. Rotenone-containing extracts are taken from the roots, seeds, and leaves of the various plants. Formulations include crystalline preparations (approximately 95% pure), emulsified solutions (approximately 50% pure), and dusts (approximately 0.75 to 5% pure). This profile refers to the crystalline preparation unless otherwise noted.

Formulation: Formulations include crystalline preparations (approximately 95% pure), emulsified solutions (approximately 50% pure), and dusts (approximately 0.75 - 5% pure). Toxicological Effects:

• Acute toxicity: Local effects on the body include conjunctivitis, dermatitis, sore throat, and congestion. Ingestion produces effects ranging from mild irritation to vomiting. Inhalation of high doses can cause increased respiration followed by depression and convulsions. The compound can cause a mild rash in humans and is a strong eye irritant to rabbits [2,8]. The oral LD50 of rotenone ranges from 132 to 1500 mg/kg in rats. The reported LD50 of rotenone in white mice is 350 mg/kg [12]. A spray of 5% rotenone in water was fatal to a 100-pound pig when exposed to 250 cubic centimeters (mL) of the airborne mixture [2]. In rats and dogs exposed to rotenone in dust form, the inhalation fatal dose was uniformly smaller than the oral fatal dose [2]. Rotenone is believed to be moderately toxic to humans with an oral lethal dose estimated from 300 to 500 mg/kg [2]. Human fatalities are rare, perhaps because rotenone is usually sold in low concentrations (1 to 5% formulation) and because its irritating action causes prompt vomiting. The mean particle size of the powder determines the inhalation toxicity. Rotenone may be more toxic when inhaled than when ingested [2], especially if the mean particle size is very small and particles can enter the deep regions of the lungs.
• Chronic toxicity: Growth retardation and vomiting resulted from chronic exposures of rats and dogs. Rats fed diets containing rotenone at doses up to 2.5 mg/kg for 2 years developed no pathological changes that could be attributed to rotenone [53]. Dogs fed doses of rotenone up to 50 mg/kg/day for 28 days experienced vomiting and excessive salivation, but no decreased weight gain [53]. Dogs fed rotenone for six months at doses up to 10 mg/kg/day had reduced food consumption and therefore reduced weight gain. At the highest dose, blood chemistry was adversely affected [53], possibly due to gastointestinal lesions and chronic bleeding. Examination of 35 tissue types revealed only one type of lesion that might have been associated with exposure to the test chemical: lesions of the GI tract [53].
• Reproductive effects: Pregnant rats fed 10 mg/kg/day on days 6 through 15 of gestation experienced decreased fecundity, increased fetal resorption, and lower birthweight [23,53]. Very high maternal mortality was seen at this dose. The 2.5 mg/kg/day dose produced no observable maternal toxicity or adverse effect on fetal development [2]. Fetotoxicity and failure of offspring are reported in guinea pigs at doses of 4.5 and 9.0 mg/kg/day for an unspecified period [2]. Thus reproductive effects seem unlikely in humans at expected exposures.
• Teratogenic effects: Pregnant rats fed 5 mg/kg/day produced a significant number of young with skeletal deformities [23,53]. The effects were not observed at the 10 mg/kg/day level, so the data do not provide convincing evidence of teratogenicity [2,23] because the effects do not appear to be dose-related. Thus, the evidence for teratogenicity is inconclusive.
• Mutagenic effects: The compound was determined to be nonmutagenic to bacteria and yeast and in treated mice and rats. However, it was shown to cause mutations in some cultured mouse cells [2,23]. In summary, the data regarding the mutagenicity of rotenone are inclusive [4].
• Carcinogenic effects: Studies in rats and hamsters have provided limited evidence for carcinogenic activity of rotenone. No evidence of carcinogenic activity was seen in hamsters at oral doses as high as 120 mg/kg/day for a period of 18 months [54]. Studies of two species of rats evidenced no statistically significant cancerous changes in any organ site, including mammary glands, at oral doses of up to 75 mg/kg/day for 18 months [54]. Significant increases in mammary tumors have been reported in albino rats with intraperitoneal doses of 1.7 mg/kg/day for 42 days [54], and in Wistar rats at approximately 1.5 mg/kg/day orally for 8 to 12 months [54]. In the latter study, however, higher dose rates (3.75 and 7.5 mg/kg/day) over the same period did not produce increased tumors [54]. Thus, the evidence for carcinogenicity is inconclusive.
• Organ toxicity: Chronic exposure may produce changes in the liver and kidneys as indicated by the animal studies cited above.

• Fate in humans and animals: Absorption in the stomach and intestines is relatively slow and incomplete, although fats and oils promote its uptake. The liver breaks down the compound fairly effectively [2]. Animal studies indicate that possible metabolites are carbon dioxide and a more water-soluble compound that can be excreted in the urine [2]. Studies indicated that approximately 20% of the applied oral dose (and probably most of the absorbed dose) may be eliminated from animal systems within 24 hours [2].

Ecological Effects:

• Effects on birds: Rotenone is slightly toxic to wildfowl. The LD50 values for rotenone in mallards and pheasants are (greater than) 2000 mg/kg and 1680 mg/kg respectively [50]. A dietary LC50 of 4500 to 7000 ppm is reported in Japanese quail [48].
• Effects on aquatic organisms: Since rotenone is used as a fish toxin (piscicide), it follows that it is very highly toxic to fish. Reported 96-hour LC50s were 0.031 mg/L in rainbow trout, 0.0026 mg/L in channel catfish, and 0.023 mg/L in bluegill for the 44% pure formulation [50]. Aquatic invertebrates have a wide range of sensitivity to rotenone with 48-hour EC50 values ranging from 0.002 to 100 mg/L [50]. The compound is not expected to accumulate appreciably in aquatic organisms. The bioconcentration factor for rotenone in the sunfish is 181 times the ambient water concentration. In addition the highly toxic nature of this substance to aquatic organisms means that there is little survival of the organisms that accumulate the compound.
• Effects on other organisms: The compound is nontoxic to bees. However, it is toxic to bees when used in combination with pyrethrum [12].

Environmental Fate:

• Breakdown in soil and groundwater: Rotenone is rapidly broken down in soil and in water. The half-life in both of these environments is between 1 and 3 days [51]. It does not readily leach from soil [51], and it is not expected to be a groundwater pollutant. Rotenone breaks down readily by exposure to sunlight [12]. Nearly all of the toxicity of the compound is lost in 5 to 6 days of spring sunlight or 2 to 3 days of summer sunlight.
• Breakdown in water: Rotenone is rapidly broken down in soil and in water. The half-life in both of these environments is between 1 and 3 days [51]. It does not readily leach from soil [51], and it is not expected to be a groundwater pollutant. Rotenone breaks down readily by exposure to sunlight [12]. Nearly all of the toxicity of the compound is lost in 5 to 6 days of spring sunlight or 2 to 3 days of summer sunlight.
• Breakdown in vegetation: Rotenone is a highly active but short-lived photosensitizer. This means that an organism consuming the compound develops a strong sensitivity to the sun for a short time. A number of photodecomposition products are formed when bean leaves are exposed to light. It is also sensitive to heat, with much of the rotenone quickly lost at high temperatures.

Physical Properties:

• Appearance: Not Available
• Chemical Name: (2R,6aS,12aS)-1,2,6,6a,12,12a-hexahydro-2-isopropenyl-8,9-dimethoxychromeno[3,4-b]furo[2,3-h]chromen-6-one
• CAS Number: 83-79-4
• Molecular Weight: 394.43
• Water Solubility: 15 mg/L @ 100 C [12], slightly soluble in water
• Solubility in Other Solvents: s. in acetone, carbon disulfide and chloroform; s.s in alcohols and carbon tetrachloride [12]
• Melting Point: 163 C [12]
• Vapor Pressure: <1 mPa @ 20 C [12]
• Partition Coefficient: Not Available
• AdsorptionCoefficient: 10,000 [51]

Exposure Guidelines:

• ADI: Not Available
• MCL: Not Available
• RfD: 0.004 mg/kg/day [30]
• PEL: 5 mg/m3 (8-hour) [23]
• HA: Not Available
• TLV: Not Available

Basic Manufacturer:

Fairfield American Corp.
238 Wilson Ave
Newark, NJ 07105

• Phone: 201-589-0263
• Emergency: Not Available
  

References:

References for the information in this PIP can be found in Reference List Number 2

DISCLAIMER: The information in this profile does not in any way replace or supersede the information on the pesticide product labeling or other regulatory requirements. Please refer to the pesticide product labeling.