Pyrethroid metabolism: comparative fate in rats of tralomethrin, tralocythrin, deltamethrin, and (1R,.alpha.S)-cis-cypermethrin

Cole, Loretta M.; Ruzo, Luis O.; Wood, E.; Casida, John E.

doi:10.1021/jf00112a003

Cited by 47 publications

(29 citation statements)

References 9 publications

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“…Products retaining the ester linkage were found in feces, while hydrolysis products were present in urine. The findings by Cole et al (1982) are in agreement with those of Crawford et al (1981a, b) and Ruzo et al (1978). Hutson and Logan (1986) reported on the metabolic fate in rats of WL85871, which was a mixture of two isomers of cypermethrin [(1R, cis) aS and (1S, cis) aR].…”

Section: Cypermethrinsupporting

confidence: 91%

“…The tables were developed from available pathway data published in the literature (Anadon et al 1996;Cole et al 1982;Crawford and Hutson 1977;Hutson and Logan 1986;Izumi et al 1984;Kaneko et al 1987;Kaneko and Miyamoto 2001;Miyamoto et al 1974;Nakamura et al 2007;Ruzo et al 1978;Staiger and Quistad 1984;Tomigahara et al 1994aTomigahara et al ,b, c, 1996Tomigahara et al , 1997Ueda et al 1975) and from physiological models (Mirfazaelian et al 2006) developed from the pathways. A preliminary physiological model for allethrin is presented in Fig.…”

Section: In Vivo Metabolism Of 1pyrethroid Insecticidesmentioning

confidence: 99%

“…The unlabeled standard compounds used for metabolite identification were described by Ruzo and Casida (1981), Ruzo et al (1978), and Unai and Casida (1977). Separation and identification of metabolites was achieved on F254 silica gel 60 TLC chromatoplates (Cole et al 1982).…”

Section: Cypermethrinmentioning

confidence: 99%

“…Cole et al (1982) recovered 100% of a 14 C-benzyl-labeled dose (0.12 mg/kg) of cypermethrin [(1R, aS)-cis cypermethrin (CAS no. 65731-84-2)] in the urine (62.9%), feces (33.8%) and tissue (3.3%) of rats.…”

Section: Cypermethrinmentioning

confidence: 99%

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Parameters for Pyrethroid Insecticide QSAR and PBPK/PD Models for Human Risk Assessment

Knaak

Dary²,

Zhang

et al. 2012

Reviews of Environmental Contamination and Toxicology

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In this review we have examined the status of parameters required by pyrethroid QSAR-PBPK/PD models for assessing health risks. In lieu of the chemical,biological, biochemical, and toxicological information developed on the pyrethroids since 1968, the finding of suitable parameters for QSAR and PBPK/PD model development was a monumental task. The most useful information obtained came from rat toxicokinetic studies (i.e., absorption, distribution, and excretion), metabolism studies with 14C-cyclopropane- and alcohol-labeled pyrethroids, the use of known chiral isomers in the metabolism studies and their relation to commercial products. In this review we identify the individual chiralisomers that have been used in published studies and the chiral HPLC columns available for separating them. Chiral HPLC columns are necessary for isomer identification and for developing kinetic values (Vm,, and Kin) for pyrethroid hydroxylation. Early investigators synthesized analytical standards for key pyrethroid metabolites, and these were used to confirm the identity of urinary etabolites, by using TLC. These analytical standards no longer exist, and muste resynthesized if further studies on the kinetics of the metabolism of pyrethroids are to be undertaken.In an attempt to circumvent the availability of analytical standards, several CYP450 studies were carried out using the substrate depletion method. This approach does not provide information on the products formed downstream, and may be of limited use in developing human environmental exposure PBPK/PD models that require extensive urinary metabolite data. Hydrolytic standards (i.e., alcohols and acids) were available to investigators who studied the carboxylesterase-catalyzed hydrolysis of several pyrethroid insecticides. The data generated in these studies are suitable for use in developing human exposure PBPK/PD models.Tissue:blood partition coefficients were developed for the parent pyrethroids and their metabolites, by using a published mechanistic model introduced by Poulin and Thiele (2002a; b) and log DpH 7.4 values. The estimated coefficients, especially those of adipose tissue, were too high and had to be corrected by using a procedure in which the proportion of parent or metabolite residues that are unbound to plasma albumin is considered, as described in the GastroPlus model (Simulations Plus, Inc.,Lancaster, CA). The literature suggested that Km values be adjusted by multiplying Km by the substrate (decimal amount) that is unbound to microsomal or CYPprotein. Mirfazaelian et al. (2006) used flow- and diffusion-limited compartments in their deltamethrin model. The addition of permeability areas (PA) having diffusion limits, such as the fat and slowly perfused compartments, enabled the investigators to bring model predictions in line with in vivo data.There appears to be large differences in the manner and rate of absorption of the pyrethroids from the gastrointestinal tract, implying that GI advanced compartmental transit models (ACAT) need to be included in PBPK mo...

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Section: Cypermethrinsupporting

confidence: 91%

Section: In Vivo Metabolism Of 1pyrethroid Insecticidesmentioning

confidence: 99%

Section: Cypermethrinmentioning

confidence: 99%

Section: Cypermethrinmentioning

confidence: 99%

See 2 more Smart Citations

Parameters for Pyrethroid Insecticide QSAR and PBPK/PD Models for Human Risk Assessment

Knaak

Dary²,

Zhang

et al. 2012

Reviews of Environmental Contamination and Toxicology

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“…Insecticidal activity is enhanced as tralomethrin is debrominated to deltamethrin and tralocythrin is debrominated to cypermethrin (Cole et al 1982). Microgranulomatous lesions in mouse liver, lymph nodes, and spleen were shown to be induced by high doses of fenvalerate in 2-yr feeding studies (Parker et al 1983;Okuno et al 1986).…”

Section: Biotransformationmentioning

confidence: 99%

Comparative Toxicology of the Pyrethroid Insecticides

Bradbury¹,

Coats

1989

Reviews of Environmental Contamination and Toxicology

275

142

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Pyrethroids

Pap¹

2002

Encyclopedia of Agrochemicals

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The insecticidal synthetic pyrethroids are chemical analogs of the natural pyrethrins occurring in the flower of the Chrysanthemum cinerariaefolium plant. They represent an extensively developed insecticide group with 40 established compounds. Of the 40 commercialized active ingredients, 37 are esters. The application rate of the most potent agricultural pyrethroids is very low, ranging between 5 and 20 g/ha, representing an acceptable environmental load. Pyrethroids are also regarded as safe compounds to warm‐blooded animals and generally to the environment; however, they have some adverse effects on mites, beneficial insects, and aquatic organisms. Pyrethroids are contact nerve poisons acting on gating kinetics of sodium channel in nerve membrane. This action is highly stereoselective. Due to this specific action and their extensive use, the risk of resistance development is relatively high in the targeted insect pest populations. Consequently, resistance management strategies are urgently needed to sustain their appropriate field performance. The registered tendencies of pyrethroid usage and the recent trends in R&D both suggest that this particular group of compounds has been playing an integrated part in present pest management as it is described in our comprehensive survey. Natural Pyrethrin PyrethrinI as the Lead Structure of the Synthetic Pyrethroids Stereochemistry How to Define Pyrethroids Nomenclature Physicochemical Properties Agricultural Use Chemistry Biological Activity, Mode of Action, Metabolism

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Pyrethroid metabolism: comparative fate in rats of tralomethrin, tralocythrin, deltamethrin, and (1R,.alpha.S)-cis-cypermethrin

Cited by 47 publications

References 9 publications

Parameters for Pyrethroid Insecticide QSAR and PBPK/PD Models for Human Risk Assessment

Parameters for Pyrethroid Insecticide QSAR and PBPK/PD Models for Human Risk Assessment

Comparative Toxicology of the Pyrethroid Insecticides

Pyrethroids

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