The toxicity and metabolism of the pyrethroidscis-andtrans-cypermethrin in rainbow trout,Salmo gairdneri

Abstract

1. The toxicity of cis- and trans-cypermethrin to rainbow trout was investigated and the concentrations of the two isomers in brain associated with toxic signs (excitability and loss of equilibrium) were determined. cis-Cypermethrin and trans-cypermethrin were equally toxic and showed similar brain levels associated with toxic signs (cis:0.25 micrograms/g, mean (range 0.07-0.53); trans:0.17 micrograms/g (0.07-0.31]. 2. Orally administered cypermethrin was less toxic than predicted, probably due to poor intestinal uptake. Toxicity was due to absorption via the gills of unchanged pyrethroid excreted from the intestine into the water. 3. The metabolism of the radiolabelled insecticides, [14C-cyclopropyl]- and [14C-benzyl]-cis- and trans-cypermethrin has been investigated in vivo and in vitro. 4. The principal route of elimination in vivo was the bile, with 20-28% dose excreted as biliary metabolites in 24 h. No difference in the rates of elimination of the cis and trans isomers was observed. 5. cis-Cypermethrin was metabolized primarily to the glucuronide of 4'-hydroxy-cypermethrin (80% total bile radioactivity), together with dichlorovinyldimethylcyclopropanecarboxylic acid and its glucuronide, 3-(4-hydroxyphenoxy)benzoic acid (4'-hydroxy-3BPA) and its ester and ether glucuronides, 3-phenoxybenzoyl glucuronide and 4'-hydroxy-3BPA sulphate were detected. trans-Cypermethrin was metabolized to the same products, but with only 36% as 4'-hydroxy-cypermethrin glucuronide.

Effects of cypermethrin on rainbow trout (Oncorhynchus mykiss)

“…Because they are highly lipophilic (attracted to the non-water soluble components of cells), pyrethroids are likely to be strongly absorbed by the gills, even from water containing low levels of pyrethroids (Smith and Stratton, 1986). Edwards et al (1986) reported acute toxicity symptoms of cypermethrin in rainbow trout such as, gill flailing, hyperactivity, loss of buoyancy and inability to remain upright.…”

Distribution, Metabolism and Toxic Effects of Beta-Cypermethrin in Lizards ( Eremias argus ) Following Oral Administration

“…Based on these results, after dosing, the BCYP rapidly centralized in stomach, quickly transferred to intestine then partly or mostly were eliminated. Studies [16,36,37] in the fish, mammals, and birds have shown that the metabolites of CYP include DCVA and PBA. Sampling the last three points' sand, the DCVA and PBA were detected (Fig.…”

Separation of Chiral Pyrethroid Pesticides and Application in Pharmacokinetics Research and Human Exposure Assessment

“…The experiment results show that ionic bonded CSP is more efficient than covalent bonded CSP. Edwards et al (Edwards et al, 1987) separated 3 pair out of the 4 pair enantiomers of the cypermethrin by using cellulose derivative chiral stationary phase with hexane and isopropanol used as the mobile phase, and the two enantiomers of the alpha-cypermethrin were also well separated. Schurig et al (Schurig et al, 1996) partly separated the two enantiomers of alphacypermethrin on cyclodextrins chiral stationary phase by using methanol / water as mobile phase.…”

“…4 showed, 8 isomers of cypermethrin and cyfluthrin were separated, and the separation method was used to analysis the isomers of cypermethrin in pork samples The following Table 2 is made for the summary. (Maguire, 1990) cypermethrin Daicel chiracel OD 6 peaks (Edwards et al, 1997) cypermethrin Glycine Derivative I~II 8 peaks (Naobumi et al, 1990 ) phenothrin 10% QF-1 Sumipax OA-2000 6peaks (Doi et al, 1985) deltamethrin RP-8/Lichrosorb Si-60 1 peaks (Mourot et al, 1979) cypermethrin Pirkle type Amino column 5 peaks cyfluthrin Dupont zorbax 5 peaks (Tephem et al, 1990) cypermethrin Sumichiral OA-2500-I, Chirex DOG-3019-DO 4 peaks cis-permethrin, transpermethrin Sumichiral OA-2500-I each 2 peaks fenvalerate Pirkle I-A 4peaks (Cayley & Simpson, 1986) fenvalerate Brush-type chiral stationary phase 4peaks (Lee et al, 1987) permethrin Brush-type ligand exchange chiral stationary phase 4peaks (Dondi et al, 1999) tetramethrin OA-4700 pirkle column and -cyclodextrin 4peaks (Deng, 2004) prallethrin, Bioallethrin, prallethrin, cyphenothrin Cellulose each 2peaks (Xu, 2003) cis-bifenthrin (BF)，permethrin (PM) Sumichiral OA-2500-I BF-2peaks, PM-2peaks cypermethrin、cyfluthrin Chirex 00G-3019-OD column 8 peaks (Mancini et al, 2004) fenpropathrin，beta-cypermethrin Chiralcel CD each 2 peaks S, R-bioallethrin -cyclodextrin as chiral additive, C8 column 2 peaks cis-cypermethrin ，trans-cypermethrin Cellulose-tris(3,5-dimethylphenylcarbamate) each 2peaks (Wang, 2006) cypermethrin Supelcosil LC-CN column coupled with Chiralcel OD-H 7 peaks (Ta et al, 2006) cis-cypermethrin Chiralcel CD column 2 peaks (Edwards et al, 1987 ) bifenthrin and fenpropathrin…”