SPECTRUM

Chemical Fact Sheet

Chemical Abstract Number (CAS #) 52645531
CASRN 52645-53-1
SynonymsAmbush
Cyclopropanecarboxylic acid, 3-(2,2-dichlorethenyl)-2,2-dimethyl-, (3-phenoxyphenyl)methyl ester
Permethrin
Ectiban
Pertox
Persect
Indothrin
Analytical Methods EPA Method 508
EPA Method 608.2
Molecular FormulaC21H20Cl2O3

Link to the National Library of Medicine's Hazardous Substances
Database for more details on this compound.

Use Medication (vet): ectoparasiticide It has a potential application for forest protection and vector control for the control of noxious insects in the household and on cattle, for the control of body lice, and in mosquito nets. Nematocide, acaricide Control of larvae (and also adults and eggs) of chewing lepidopterous and coleopterous insect pests on pome fruit, stone fruit, berry fruit, citrus fruit,vines, olives, vegetables, cereals, maize, oilseed rape, cotton, tobacco, soya beans, and in conifer nurseries; whiteflies and other glasshouse pests on glasshouse cucumbers, tomatoes, and ornamentals; and sciarid flies and phorid flies on mushrooms. Also used for control of crawling and flying insects (e.g flies, ants, fleas, cockroaches, silverfish, etc.) in public health, and in agricultural premises including animals houses; and as an ectoparasiticide on animals. Insecticide Pyrethrins
Consumption Patterns Tick repellent
Apparent Color Pale brown liquid
Boiling Point ca 200 deg C at 0.01 mm Hg
Melting Point 34-35 deg C
Molecular Weight 391.29
Density 1.19 - 1.27 at 20 deg C
Sensitivity Data Mild irritant to skin and eyes. Technical permethrin Immediately irritating to the eye. Pyrethrins The chief effect from exposure is skin rash particularly on moist areas of the skin. May irritate the eyes. Pyrethroids
Environmental Impact Permethrin will be released to the environment primarily during agricultural spraying operations. In the ambient atmosphere, permethrin is expected to exist almost entirely in the particulate-phase because of its low vapor pressure. Degradation of vapor phase permethrin by reaction with photochemically produced hydroxyl radicals (estimated half-life of 9.9 hrs) may take place. Particulate phase permethrin will be removed from air via dry deposition. In soil, a degradation half-life of 30 days was estimated for permethrin and its strong adsorption to soil suggests that leaching is not important. Biodegradation will be important. Photolysis may occur on soil surfaces exposed to sunlight and hydrolysis in alkaline moist soils may contribute to the removal of permethrin from soil. In water, permethrin may hydrolyze producing 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid and 3-phenoxybenzyl alcohol (estimated half-life of 20 days at pH 9). Biodegradation, bioconcentration in fish, and photolysis in near-surface waters exposed to sunlight may be important processes in water. Furthermore, adsorption from the water column to sediments and suspended material will be important (Koc of 63,100). Volatilization will not be important because of its low Henry'a Law constant. Exposure of the general population to permethrin may occur through ingestion of contaminated foods as well as inhalation of dust and dermal contact resulting from its use. Workers may be exposed via dermal contact and inhalation of dust.
Environmental Fate TERRESTRIAL FATE: According to all available data in the U.S. Department of Agriculture's Pesticide Properties Database, a degradation half-life of 30 days was estimated for permethrin in soil . The half-life of permethrin in aerobically incubated soil is less than 4 weeks and is 32 to greater than 64 days in anaerobic flooded soils . In moist alkaline soils, hydrolysis probably takes place in conjunction with biodegradation; estimated aqueous hydrolysis half-life of 20 days at pH 9 . An experimental Koc value of 63,100 indicates no soil mobility and strong soil adsorption. Photodegradation half-lives of 5-17 days were determined for permethrin on thin films suggesting that permethrin may be removed from soil surfaces via direct photolysis. AQUATIC FATE: An experimental Koc value of 63,096 indicates that adsorption from the water column to sediment and suspended solids will occur. A BCF of about 480 for Sheepshead minnow (Cyprinodon variegatus) indicates that bioconcentration in fish may be an important aquatic fate process. The major metabolic pathway of permethrin involves the hydrolysis of the ester bond producing 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid and 3-phenoxybenzyl alcohol ; estimated half-life of 20 days at pH 9 . Permethrin in near-surface waters will be susceptible to photolysis; photolysis half-lives of 27.1 and 19.6 hrs were determined for respective cis- and trans-isomers in 800 mL pond water exposed to sunlight . Volatilization from water will not be an important removal process based on an estimated Henry's Law constant of 2.51X10-8 atm-cu m/mole at 20 deg C. ATMOSPHERIC FATE: Based on an experimental vapor pressure of 9.75.X10-9 mm Hg at 20 deg C , permethrin is expected to exist almost entirely in the particulate phase in the ambient atmosphere . Vapor phase permethrin will degrade in the ambient atmosphere by reaction with photochemically formed hydroxyl radicals; the half-life for this reaction in air can be estimated to be about 9.9 hrs(3,SRC). Photodegradation half-lives of 5-17 days were determined for permethrin on thin films suggesting that permethrin may be removed from the atmosphere via direct photolysis. Particulate phase permethrin is removed via dry deposition.
Drinking Water Impact Permethrin was detected 6 hrs post-application at concns of 17 and 18 ng/L in 2 of 6 samples from a creek approximately 60-100 m from a potato field where permethrin was applied via aerial spraying .

DISCLAIMER - Please Read

Florida-Spectrum List of Services
Florida-Spectrum Homepage