Pesticides permethrin

Hiatt, C.W., Haskins, W.T., Olivier, L. (1960) The action of sunlight on sodium pentachlorophenate. Am. J. Trop. Med. Hyg. 9,527-531. Hidaka, H., Nohara, K., Zhao, J., Serpone, N., Pelizzetti, E. (1992) Photo-oxidative degradation of the pesticide permethrin catalyzed by irradiated Ti02 semiconductor slurries in aqueous media. J. Photochem. Photobiol. A Chem. 64, 247-254. 

TiC>2 photo catalysis has demonstrated efficacy against a range of agrochemicals such as herbicides and pesticides. One of the first reports detailed the mineralisation of the pesticide permethrin in Ti02 hexane/water slurry. Using solar irradiation 90% photodegradation of a 17 000 ppm solution was achieved in 8 h [123]. 

It is practically impossible to identify all chemicals in a sample and yet such procedures are needed to detect the presence of unanticipated chemicals and to signal new or potential problems. Extracts of water, sediment, and biota have been extensively fractionated and analyzed by multidetector gas chromatography [ 145]. Compounds detected in addition to the usual hydrocarbons, chlorinated hydrocarbons, and organochlorine pesticides included chlorinated isocyanates and aniUnes, cyclohexanol, cyclohexanone, aromatic ketones and acids, thiophenes, nonyl- and cumyl-phenols, carbazoles, quinolines, indoles and tolyltriazoles, and the pesticides permethrin, triclosan, and bromacil. 

Encapsulated fonofos, a soil insecticide, was developed to coat seeds before they were planted (72). Encapsulation reduces oral toxicity 100-fold and dermal toxicity 10-fold while extending activity of the fonofos. Other encapsulated pesticides available include permethrin and parathion (69). Significantly, all commercial encapsulated pesticides are prepared by interfacial polymeri2ation. 

Permethrin, a pyrethrin pesticide, decreased the inhibition of brain cholinesterase activity by methyl parathion, but methyl parathion decreased the LD50 of permethrin when the two pesticides were simultaneously administered to rats (Ortiz et al. 1995). The potentiation of permethrin lethality may be due to the inhibition by methyl parathion of carboxylesterase, which metabolizes permethrin. 

The R/S ratios for permethrin and phenothrin in Table 3 are 204 and 283, respectively. The Hiroyama strain showed high cross-resistance to permethrin and phenothrin, whereas the R/S ratio for natural pyrethrins was only 7. Moreover, the R/S ratio for racemic allethrin was 97, indicating the slow development of resistance compared with permethrin and phenothrin. These results agree well with the findings of Sawicki et al. [49], who reported that pyrethroids with the cyclopentenolone ring showed only a slight resistance at the International Congress of Pesticide Chemistry in Ottawa in 1986. 

Gambrell et al. [223] have discussed the recovery of DDT, Kepone and Permethrin added to soil suspensions incubated under controlled redox potential and pH conditions to determine the effect of time on the levels of the insecticides and their degradation products. Samples were analysed by gas chromatography, pH and redox potential affected the persistence of pesticides to different degrees. The recovery of DDT was affected by redox potential but not by pH. 

Water samples were taken on April 21, August 6, and December 11, 1980 as described and illustrated In Table I and Figure 1, respectively. All samples were analyzed for the following pesticides, using routine methods derived from the Pesticide Analytical Manual, PAM, (J ), and shown to contain less than the Indicated amounts (parts per million) captan <0.2 dlfolatan <0.1 carbaryl <0.01 methylparathlon <0.1 permethrin <0.01 azlnphosmethyl <0.1. Cited thresholds were above the detection limits. 

Pyrethrins are naturally occurring pesticides derived from chrysanthemum plants. They are active against many insects and mites. Over-the-counter liquid and gel preparations of pyrethrins with piperonyl butoxide are available for the treatment of pediculosis (piperonyl butoxide inhibits the hydrolytic enzymes that metabolize the pyrethrins in the arthropod). A synthetic pyre-throid, permethrin (Elimite), is available by prescription. A lower concentration of permethrin (Nix) is available without prescription. Pyrethrins and permethrin are quite safe. 

Papers from the symposium on the chemistry, biochemistry, and insecticidal action of natural and synthetic pyrethroids (Helsinki 1974, Third I.U.P.A.C. International Congress on Pesticide Chemistry) and the proceedings of a symposium on synthetic pyrethroids held at the 172nd A.C.S. Meeting (San Francisco, 1976) have been published. Other pyrethroid papers of interest include C n.m.r. spectra of synthetic pyrethroids (cf. Vol. 7, p. 20), gd.c. analysis of permethrin and bioresmethrin, further work (Vol. 7, p. 10) on permethrin metabolism in rats ... 

Dehydrohalogenation.2 K02 in DMF effects dehydrohalogenation of dichloro-vinyl groups to chloroethynyl groups and also of other polychloro groups. This reaction is of considerable interest as a means of detoxifying several polychlorinated pesticides, such as cis-permethrin (1) and DDT (3). 

Appendix B provides brief case studies of two pesticides, glyphosate and permethrin, for which a pre-existing risk assessment can help to put biomonitoring results into perspective. In both cases, the Environmental Protection Agency (EPA) has evaluated risks for a wide array of exposure scenarios as part of the reregistration process, and there are biomonitoring data whose interpretation could benefit from these risk assessments. 

Bioaccumulatlon of some pesticides (fenitrothion, aminocarb, permethrin) with real or potential application in forestry in Canada has been examined in laboratory experiments using larval rainbow trout and common duckweed. Bioaccumulation of an aromatic hydrocarbon, fluorene, has also been examined since some commercial formulations employ hydrocarbon solvents. Laboratory exposures of fish or plants were carried out by placing the organisms in dilute aqueous solutions of C labelled pesticide or hydrocarbon, and by measuring transfer of radioactivity from water to fish or plants. After transfer of fish or plants to untreated water, loss of radioactivity was measured similarly. These measures allowed calculation of uptake and depuration rate constants which were used to predict residue accumulations under various exposure conditions. Predicted residue accumulations agreed substantially with other predictive equations in the literature and with reported field observations. 

Permethrin is classified as a restricted use pesticide (RUP) because of high toxicity to fish and aquatic organisms. Permethrin is used to control Nantucket pine tip moths, coneworms, seed bugs, and range caterpillars.4,5... 

The majority of pyrethroid insecticides have low volatilities. The heavily used synthetic pyrethroid permethrin is classified as nonvolatile on the basis of its vapor pressure (1.3 x 10 kPa at 20 °C) and is rarely found in indoor air. However, it has recently been reported to be the major pesticide residue found in house dust (USEPA, 2000d). Cyper-methrin [( )-a-cyano-3-phenoxybenzyl-( )-cA,frani -3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate] and cyfluthrin [cyano(4-fluoro-3-phenoxy-phenyl)methyl 3-(2,2-dichloro-ethenyl)-2,2-dimethylcyclopropanecarboxylate] are two other low-volatility pyrethroids commonly used for indoor flea and cockroach control. 

The influence of the volatility of a pesticide on measurable indoor air levels is evident by comparing semivolatile chlorpyrifos with nonvolatile permethrin. Room-air concentrations of these two insecticides were found to be comparable (means of 30 and 42p.g/m, respectively) 0-2h after broadcast spraying, but the air levels of permethrin declined so rapidly that nothing ([Pg.109]

SYNS AI3-29158 BW-21-Z ECTIBAN EXMIN O EMC 33297 EMC 41655 ICI-PP 557 KESTREL (Pesticide) NDRC-143 NIA 33297 OUTFLANK OUTFLANK-STOCKADE PERMETHRIN (USDA) PERMETRIN (HUNGARIAN) PERMETRINA (PORTUGUESE) 3-PHENOXYBENZYL ( )-3-(2,2-DICHLORO-VlNYL)-2,2-DIMETHYLCYCLOPRO-PANECARBOXYL-ATE (3-PHENOXYPHENYL)-METHYL-3-(2,2-DICHLO-RETHENYL)-2,2-DIMETHYLCYCLOPROPANECARBO-XYLATE POUNCE PP 557 S-3151 SBP-1513 TALCORD WL 43479... 

Agricultural pesticides were found to be effective insect resist agents when applied in emulsion form to wool dyebaths. Dieldrin (Fig. 16.2a), one of the original nerve poisons, is also highly toxic to mammals and aquatic life and its use has been banned in most countries. Products based on permethrin (Fig. 16.2b), a synthetic pyrethroid, are very effective against moth larvae, but have less effect on Anthrenus beetles. To overcome this disadvantage, combination products of permethrin and hexahydropyrimidine derivatives (Fig. 16.2c) have been introduced. 

The acceptable daily intakes set by the Joint Meeting on Pesticide Residues (JMPR) for cypermethrin, deltamethrin, and permethrin are 0-0.01 mg kg body weight, with acute oral reference doses for deltamethrin or permethrin of 0.05 mg kg bw. The National Institute for Occupational Safety and Health maximum allowable concentration (MAC) for pyrethrins at an 8 h time-weighted average is 5 mg m ... 

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