Fenvalerate applications

Moffett, J.O., A. Stoner, and R.M. Ahring. 1982. Effect of fenvalerate applications on honey bees in flowering alfalfa. Southwestern Entomol. 7 111-115. 

Pyrethroids are used primarily for the control of household and agricultural insect pests, and secondarily in industrial, stored product, and veterinary applications. They are especially advantageous for use in northern climates because their toxicity is enhanced at low temperatures (Smith and Stratton 1986). Synthetic pyrethroid insecticides, including fenvalerate, are used as alternatives... 

Various plants sprayed with 0.25 kg fenvalerate/ha all had measurable residues 7 days after application, and nondetectable residues 15 to 30 days after treatment (Jain etal. 1979). Washing plants in cold water to remove the pesticide was effective only on the initial day of application, removing 30 to 50%. Afterward, only 3 to 13% could be removed by washing. Cooking removed 71 to 88% of the fenvalerate residues on the initial day of treatment but in later samplings, removal was 68 to 70% in spinach (Spinacea oleracea) and tomatoes, and 38 to 40% in okra (Abelmoschus esculentus) and cauliflower (Brassica oleracea botrytis) (Jain et al. 1979). 

Adsorption and persistence in plants can be modified by other chemicals or by selected carriers, although mechanisms to account for these phenomena are unclear. The application mixture influences adsorption and persistence of fenvalerate. For example, interception and persistence in sugarcane were increased when fenvalerate was applied in a 25% water/75% soybean oil mixture vs. water or soybean oil alone (Smith et al. 1989). Also, biocidal properties of fenvalerate residues on cotton foliage were increased up to 100% due to enhanced persistence of fenvalerate in the presence of toxaphene (Brown et al. 1982). 

Terrestrial plants are relatively unaffected by fenvalerate at recommended application rates, as judged by negligible uptake of fenvalerate from treated soils, formation of numerous fenvalerate conjugates that are pharmacologically inactive, and metabolism of the liberated cyano group into amino acids and eventually carbohydrate and protein (Miyamoto 1988). 

Adverse effects of fenvalerate on survival of terrestrial arthropods were observed at 0.002 to 0.015 pg whole-body topical application, O.llkg/ha aerial application, 5.4 mg/kg in the soil, 50 mg/kg in the diet, and 1.4 g/ant mound (Table 20.4). Synthetic pyrethroids are more effective in biological systems at low temperatures. The relative sensitivity of insects when compared with mammals is attributed in part to this negative temperature coefficient. Thus, warm-blooded animals are less affected than insects and other poikilotherms (Klaassen etal. 1986). Fenvalerate, for example, showed a negative correlation between temperature and toxicity to crickets (Acheta pennsylvanicus), being up to 1.9 times more toxic at 15°C than at 32°C (Harris etal. 1981). A similar case is made for honey bees (Apis mellifera) (Mayer et al. 1987) and for many species of aquatic invertebrates and fish (Mayer 1987). 

In the first 2 days after application, the water column contained the majority of the fenvalerate... 

Fenvalerate toxicity is antagonized by atropine sulfate or methocarbamol, which may be effective in treating severe cases of poisoning (Hiromori et al. 1986). Conversely, some compounds exacerbate the toxicity of fenvalerate and interfere with a desired use. Domestic cats (Felis domes-ticus) treated with Fendeet (an aerosol mixture of fenvalerate and A-A-diethyl-m-toluamide) to control fleas and ticks sometimes show signs of toxicosis, such as tremors, hypersalivation, ataxia, vomiting, depression, and seizures. Signs usually appeared within hours of topical application, and females and juveniles seem to be the most sensitive groups. The demonstrated ability of N-N-diethyl-m-toluamide to enhance the dermal absorption of fenvalerate is the probable cause of toxicosis (Dorman et al. 1990). 

After last application, no detectable fenvalerate residues were found in milk after 6 h maximum residues in milk were 1.14 pg/L after 3 days, 0.42 in 4 days, and not detectable after 7 days... 

Kitten, 3 months old, died in 6 h following hypersalivation, ataxia, depression, and seizures. No histopathology at necropsy brain AChE activity normal. Fenvalerate residues, in pg/kg, were 345,000 in skin, 230 in kidney, 150 in liver, 10 in brain. Adult (4-year-old) showed signs of toxicosis 4 h after topical application by 30 h, animal had lowered body temperature, bradycardia, and other signs of fenvalerate poisoning. At death, shortly thereafter, fenvalerate residues were 1000 pg/kg in skin and 20 pg/kg in liver... 

Phillips, S.A., Jr. D.M. Clabom, and O.F. Francke. 1984. Comparison of aerial application and single-mound drenches of fenvalerate against the red imported fire ant, Solenopsis invicta Buren, in Texas. Southwestern Entomol. 9 164-168. 

Smith, S., T. Reagan, G.H. Willis, J.L. Flynn, and D.C. Rester. 1989. Fenvalerate interception by and dissipation from sugarcane foliage as affected by application technology. Bull. Environ. Contam. Toxicol. 42 30-36. 

Typical applications in calibration are reviewed and as practical example data from the determination of the pesticide fenvalerate by gas chromatography with electron capture detection are evaluated. 

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