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1.
The dissipation rate of endosulfan isomers (α and β) in seawater and sediment was studied. The disappearance rate of both isomers from seawater and pure water was compared, and the same measurements were made in both sterile and unsterile marine sediment. Flasks of water and sediment, fortified with a dispersion of a commercial endosulfan 350 g litre−1 EC, Protodan 35®, were incubated under laboratory light at room temperature for 82 days. A micro on‐line extraction method and GC‐ECD was used to determine the pesticide and its metabolites. The dissipation of endosulfan (in two phases of first‐order kinetics) occurred more rapidly in seawater than in pure water. At the end of the experiment, the concentration of α‐endosulfan in sterile sediment was four times greater than in unsterile sediment, while the dissipation rate of β‐endosulfan in unsterile sediment was approximately double that observed in sterile sediment. The dissipation of both forms in sediment occurred in a single stage. Endosulfan β‐isomer was more persistent than α‐isomer in both sterile and unsterile sediment. Dissipation of endosulfan sum of α‐ and β‐isomers in sediment at the end of the experiment ranged from 80% (sterile) to 95% (unsterile). Endosulfan sulfate was detected in water and sediment as the main metabolite. © 2000 Society of Chemical Industry  相似文献   

2.
A goat given a single dose of 14C-labeled α-[p-(1,1,3,3-tetramethylbutyl)phenyl]-ω-hydroxyhexa(oxyethylene) ([14C]TOP-6EOH) eliminated 18% of the 14C in the urine and 77% in the feces within 96 hr after dosing. Another goat (surgically modified for total bile collection) given a single dose of [14C]TOP-6EOH eliminated 81% of the 14C in the bile, 17% in the urine, and only 6% in the feces. When 14C-bile from the animal in the second study was perfused into the small intestine of a third goat, 72% of the 14C was eliminated in the feces, 20% in the bile, and 6% in the urine within 96 hr. Eighteen different types of metabolites accounting for most of the 14C in the bile and urine were isolated, derivatized, and then characterized by mass spectral analysis. The [14C]TOP-6EOH was metabolized by: (i) oxidation of the alkyl group to give alcohols and acids, (ii) oxidation of the terminal ethylene oxide moiety to an acid, (iii) cleavage of the polyoxyethylene side chain, (iv) combinations of i–iii, and (v) conjugation of the products of i–iv.  相似文献   

3.
Endosulfan (Thiodan 3 EC), a mixture of α- and β-isomers, was sprayed on 92-day-old field-grown pepper and tomato at the recommended rate of 0·61 kg AI ha-1. Plant tissue samples were collected at 1 h to 14 days after application and analysed to determine the content and dissipation rate of endosulfan isomers (α- and β-endosulfan) and the major metabolite, endosulfan sulfate. Analysis of samples was accomplished using gas chromatography-mass selective detection (GC-MSD). The results indicated the formation of endosulfan sulfate as a residue component on the plant tissues and also the relatively higher persistence of the β-isomer as compared to the α-isomer on pepper fruits. The initial total residues (α- and β-endosulfan isomers plus endosulfan sulfate) were higher on leaves than on fruits. On pepper fruits, the α-isomer, which is the more toxic to mammals, dissipated faster than the less toxic β-isomer. Total residues (α- and β-endosulfan isomers plus the sulfate metabolite) on tomato leaves revealed longer persistence (t1/2 4·6 days) compared to the total residues detected on pepper leaves (t1/2 2·0 days) 3–14 days following spraying. Persistence of the β-isomer on pepper fruits was high 3–14 days following spraying compared to on tomato fruits. This long persistence increases risk of exposure of the consumer. In addition, the longer persistence of the total residues on tomato foliage should be considered of importance for timing the safe entry of tomato harvesters due to the high mammalian toxicity of endosulfan. © 1998 Society of Chemical Industry  相似文献   

4.
Rats and chickens were each given a single oral dose (10 or 100 mg/kg body wt) of 1,1,1-trifluoro-N-[2-methyl-4-(phenylsulfonyl)phenyl-14C(U)]methanesulfonamide ([14C]perfluidone). Depending on the size of the dose, from 8.4 to 36.2% of the [14C] was eliminated in the urine and from 36.4 to 85.4% was eliminated in the feces within 48 hr after dosing. Less than 1% of the [14C] given to laying hens as [14C]perfluidone was present in the eggs produced during the first 96 hr after dosing. The percentage of the administered [14C] that remained in these animals (body with G.I. tract and contents removed) varied from 0.34 (96 hr after dosing) to 1.68% (48 hr after dosing). 14C-labeled compunds in the urine and feces from the rats and chickens were purified by solvent extraction, column chromatography, and gas-liquid chromatography, and then identified by infrared and mass spectrometry. The parent compound was the major 14C-labeled component in the urine and feces of both animals. 1,1,1-Trifluoro-N-[2-methyl-4-(3-hydroxyphenylsulfonyl)phenyl]methanesulfonamide was present in the feces of both animals. The proposed structures of other metabolites were 1,1,1-trifluoro-N-hydroxy-N-[2-methyl-4-(phenylsulfonyl)phenyl]methanesulfonamide (rat urine) and 1,1,1-trifluoro-N-{2-methyl-4-[(methylsulfonyl)-phenylsulfonyl]phenyl}methanesulfonamide (chicken urine).  相似文献   

5.
Extractable residues of endosulfan stereoisomers and its toxic metabolite, endosulfan sulfate, on a vegetable, an oilseed and a pulse crop were determined by gas-liquid chromatography. The study revealed that the alpha isomer degraded faster than the beta isomer. Beta-endosulfan accumulated during the first three days following the treatment. Endosulfan sulfate residues appeared a few days after application and decreased with time. The total endosulfan residues in the seeds from treated mustard ranged from 0.08 to 0.12 mg kg?1 and were at or below the limit of determination (0.02 mg kg?1) in chickpea seeds following harvest.  相似文献   

6.
Upon intravenous application of dihydrochlordene dicarboxylic acid-14C to rats, the radioactivity is quickly excreted, and 44% of the excreted radioactivity consists of metabolites. Nine metabolites have been isolated from feces and urine extracts. Three metabolites could be identified by means of authentic samples by thin layer chromatography, gas chromatography, and mass spectrometry: two isomers of dechlorodihydrochlordene-dicarboxylic acid (metabolites I and II, total 22.5%) and dihydrochlordene-dicarboxylic acid-dimethyl-ester (metabolite III, 11.3%).  相似文献   

7.
The excretion patterns and tissue residues were determined after single and repeated oral dosing of rats with triazophos-14C Within 4 days after a single oral dose 76.3 % of the 14C was excreted in the urine and 21.0% in the faeces. After daily application for 12 days 69.5–83.4% of the label was eliminated in urine and 30.9–18.1 % in the faeces. Following prolonged application, however, elimination is distinctly slower. Distribution of radioactive residues in organs and tissue in both test series showed no appreciable or critical concentrations of radioactivity, with the exception of the gastrointestinal tract (contents and walls). Unchanged triazophos and l-phenyl-1,2,4-triazol-3-ol-3-14C were excreted in the faeces. Renewed release of other metabolites into the gastrointestinal tract apparently does not take place. The following metabolites are detected in the urine: urea-14C (approx. 85% of the radioactivity excreted with the urine); and three compounds as conjugates with glucuronic acid, i.e. 1-phenyl-l,2,4-triazol-3-ol-3-14C (approx. 3%), l-phenylsemicarbazide-3-14C (approx. 5%), and semicarbazide-14C (approx. 5%). Two further metabolites, so far unidentified, occurred in small quantities.  相似文献   

8.
The biliary secretion of 14C was observed in conscious, bile-fistulated rats given single oral doses of [14C]carbaryl (1.5, 30, and 300 mg/kg). Over 94% of the 14C was absorbed after 12 hr. From 15 to 46% of the 14C was secreted in bile, 10–40% in urine, and less than 1% in feces 12 hr after dosing. Three metabolites were isolated from bile and identified by mass and/or NMR spectrometric methods. These metabolites were: 5,6-dihydro-5,6-dihydroxycarbaryl glucuronide (12–18% of the biliary 14C), a conjugate(s) of carbaryl (12% of the biliary 14C), and conjugated isomers of hydroxy-carbaryl (2% of the biliary 14C). The majority of the biliary 14C remains to be identified.  相似文献   

9.
Endosulfan (α,β-1,2,3,4,7,7-hexachlorobicyclo(2,2,1)-heptene-(2)-bis-hydroxymethylene(5,6)sulfite) fed daily 0.5 and 100 ppm in the diet proved significantly toxic to female rats (initial weight 40–50 g) growing on a low-protein (5%) diet as compared to those growing on a high-protein (24%) diet. The toxic symptoms which developed exclusively in low-protein-fed rats included growth retardation, low blood counts, low RNA and protein levels in liver, and high glutathione levels in liver and blood. However, no changes in the activities of liver RNase, blood glucose-6-phosphate dehydrogenase, and glutathione reductase were observed. Liver glucose-6-phosphatase activity increased significantly. Endosulfan induced an increased accumulation of perirenal adipose in rats raised both on low- and high-protein diets. Endosulfan elicited cumulative toxic manifestations as evident from the relative degree of toxicity caused by 0.5 ppm and 18 weeks feeding. α-Endosulfan, β-endosulfan, and endosulfan sulfate were recovered from adipose tissue, the recovery being higher in adipose tissue of rats raised on a low-protein diet.  相似文献   

10.
Alfalfa was root-treated with [14C]propham (isopropyl carbanilate[14C-phenyl(U)]) for 7 days and then harvested and freeze-dried. Rats and sheep were orally given either 14C-labeled alfalfa roots ([14C]root) or 14C-labeled alfalfa shoots ([14C]shoot). When the [14C]root was given, 6.5–11.0% of the 14C was excreted in the urine and 84.6–89.4% was excreted in the feces within 96 h after treatment. Less than 3% of the 14C remained in the carcass (total body—gastrointestinal tract and contents) 96 h after treatment. When [14C]shoot was given, 53.2–55.2% of the 14C was excreted in the urine, 32.1–43.4% was excreted in the feces, and the carcass contained 0.2–1.1% of the 14C 96 h after treatment. When the insoluble fraction (not extracted by a mixture of CHCl3, CH3OH, and H2O) of both alfalfa roots and shoots was fed to rats, more than 86% of the 14C was excreted in the feces and less than 3% remained in the carcass 96 h after treatment. The major radiolabeled metabolites in the urine of the sheep fed 14C shoot were purified by chromatography and identified as the sulfate ester and the glucuronic acid conjugates of isopropyl 4-hydroxycarbanilate. Metabolites in the urine of the sheep treated with [14C]root were tentatively identified as conjugated forms of isopropyl 4-hydroxycarbanilate, isopropyl 2-hydroxycarbanilate, and 4-hydroxyaniline. The combined urine of rats dosed with [14C]shoot and [14C]root contained metabolites tentatively identified as conjugated forms of isopropyl 4-hydroxycarbanilate, isopropyl 2-hydroxycarbanilate, and 4-hydroxyaniline.  相似文献   

11.
Upon single oral administration to rats, the mono-, di- and tri-glucose conjugates of [14C]-3-phenoxybenzyl alcohol ( I ) or the mono-glucose conjugate of [14C]-3-phenoxybenzoic acid ( II ) were rapidly hydrolysed and extensively eliminated in the urine mostly as the sulphate conjugate of 3-(4-hydroxyphenoxy)benzoic acid ( X ). The faecal elimination was a minor route, whereas the biliary excretion was about 42% of the dose and the glucuronide conjugates of I , II and X were common major metabolites. The biliary glucuronides were cleaved in the small intestine to the respective aglycones, which were reabsorbed, metabolised further, and excreted in the urine as the sulphate conjugate of X . Although small amounts of the mono-, di-and tri-glucosides were found in the 0.5-h blood and liver samples following oral administration of the tri-glucoside of I , they were not detected in the urine, bile or faeces. Similarly the sulphate conjugate was one of the major urinary metabolites of germ-free rats, dosed with the 14C-glucosides via the oral or the intraperitoneal route, although they were excreted unchanged in certain amounts in the urine and faeces. The glucose conjugates were cleaved in vitro by gut microflora and in various rat tissues, including blood, liver, small intestine and small intestinal mucosa. The tissue enzymes showed a different substrate specificity in hydrolysis of the glucosides. However, they were not cleaved in gastric juice, bile, pancreatic juice or urine.  相似文献   

12.
A single oral dose of [14C]tridemorph was partly, but rapidly absorbed by rats. Most of the radioactivity was excreted with a half-life of about 15 h. During 5 days, 42.6% was excreted in the urine, 46.7% in the faeces, 1.5% in the expired air and 3.4 % was still retained. 24 % was excreted in the 48 h bile. Sequential wholebody autoradiography indicated that much of the radioactivity was confined to the gastrointestinal tract, liver and kidneys. There was no unexpected uptake of radioactivity. Urinary metabolites were more polar than tridemorph and were also detected in the bile and faeces. The major metabolite in 24 h urine, accounting for 22.3% of the dose appeared to be a side-chain hydroxylated derivative. Cleavage of the morpholine ring was limited to about 1.5 % of the dose.  相似文献   

13.
A rat, given a single oral dose of [14C] cymoxanil, 1-(2-cyano-2-methoxyimino-[2-14C]-acetyl)-3-ethylurea, eliminated 91% of the radioactivity within 72 h. The urine contained 71%, the faeces 11%, and the expired air about 7% of the radiolabel; no 14C residue was found in the internal organs. Greater than 70% of the radioactivity in the urine was identified. The major metabolite was characterised as glycine, both free and conjugated, as hippuric acid and phenylaceturic acid [N-(phenylacetyl)-glycine], and probably in the form of polypeptides of low molecular weight. The other metabolites identified included 2-cyano-2-methoxyiminoacetic acid, 2-cyano-2-hydroxyiminoacetic acid and 1-ethylimidazolidine-2, 4, 5-trione. The minor metabolites included succinic acid and 2-oxoglutaric acid which indicated reincorporation of metabolic 14C. Cymoxanil, as such, was not detected in the urine.  相似文献   

14.
The disposition of the pyrethroid insecticide cypermethrin, (RS)-a-cyano-3-phenoxybenzyl (1RS)-cis, trans-3-(2,2-dichlorovinly)-2, 2-dimethylcyclopropane-carboxylate, has been studied in male and female rats following a single toxic oral dose (200mg kg−1) of two radiolabelled forms ([14C-benzyl] and [14C-cyclopropyl]) of the insecticide. The bioaccumulation and elimination of 14C-benzyl-labelled cypermethrin, following repeated administration at a sub-toxic dose (2mg kg−1), has also been studied in male and female rats. Although, at the toxic dose, radioactivity from the two radiolabelled forms was rapidly eliminated in urine and faeces, the increased excretion in the faeces, over that for low doses, was evidence that absorption was incomplete. The major pathways of metabolism involved cleavage of the ester bond, with subsequent hydroxylation and glucuronidation of the cyclopropyl acid moieties, together with hydroxylation and sulphation of the 3-phenoxybenzyl moiety. The absence of sex- or dose-dependent changes was reflected by the constant proportions of these metabolites found in the urine. Constant levels of radioactivity in tissues were achieved rapidly, generally within the first week of repeated administration. Elimination was rapid on the cessation of dosing, although less rapid from the fat and skin. The material in the fat was mainly the cis-isomers of cypermethrin, which were eliminated with a mean half-life of 18.2 days, compared with 3.4 days for the trans-isomers.  相似文献   

15.
When [14C]F3-fluorodifen (2,4′-dinitro-4-trifluoromethyl diphenylether), carbonyl-[14C]CDAA (N,N-diallyl-2-chloroacetamide), and carbonyl-14C-propachlor (2-chloro-N-isopropylacetanilide) were fed to rats, 57 to 86% of the 14C was excreted via the urine within 48 hr. Although very little radioactivity was excreted in the feces of CDAA-treated rats, 15–22% of the 14C was excreted in the feces of propachlor- of fluorodifentreated rats and an average of 8% of the 14C remained in these rats 48 hr after treatment. Oxidation of the 14C label to [14C]O2 was not a major process in the metabolism of these herbicides. The only major radioactive metabolite present in the 24-h urine of fluorodifen-treated rats, 2-nitro-4-trifluoromethylphenyl mercapturic acid, accounted for 41% of the administered dose of 14C. In the metabolism of CDAA, the corresponding mercapturic acid accounted for 76% of the dose; it was the only major metabolite present in the 24-h urine. In contrast, three major metabolites were detected in the 24-h urine of propachlortreated rats, and the mercapturic acid accounted for only 20% of the dose. The mercapturic acid of each herbicide was identified by mass spectrometry.  相似文献   

16.
The metabolism of the pyrethroid insecticide α-cyano-3-phenoxybenzyl 2,2,3,3-tetramethylcyclopropanecarboxylate (WL 41706) has been studied in rats using two forms of 14C-labelling (benzyl- and cyclopropyl-). Excretion of benzyl?14C was rapid, 57% of the administered dose being eliminated in the urine 48 h after treatment and 40% in the faeces. No significant sex difference was observed. The amount of radioactivity excreted via expired gases was 0.005% of the administered dose and less than 1.5% of the dose remained in the animals 8 days after treatment. The mean percentage recovery of administered dose was 104% for male rats and 97% for female rats. Urinary and faecal metabolites from these rats, and from rats dosed similarly with [cyclopropyl?14C]-WL 41706 were studied. The rapid metabolism of WL 41706 is due to efficient cleavage of the ester bond by rats in vivo to afford 2,2,3,3-tetramethylcyclopropanecarboxylic acid (partly as glucuronide) and the 3-phenoxybenzyl moiety. Before this cleavage occurs, however, about half of the intake suffers aryl hydroxylation giving the α-cyano-3-(4-hydroxyphenoxy)benzyl ester, part of which is excreted in the bile as a conjugate(s) and part of which is cleaved and eliminated as the O-sulphate of 3-(4-hydroxyphenoxy)benzoic acid and the glucuronide of 2,2,3,3-tetramethylcyclopropanecarboxylic acid. A minor amount of hydroxylation occurs at a trans-methyl group on the cyclopropane acid moiety. The metabolism of WL 41706 by rat liver occurs mainly in the microsomes and mainly via oxidative processes.  相似文献   

17.
A single oral dose of 0.14 mg kg?1 of [14C] flocoumafen to rat, which gave a transient, non-lethal, effect, was rapidly absorbed, radioactivity appearing in the blood maximally at 4 h and falling to half maximum value by 8 h. The maximum effect on prothrombin time was at 24 h and the value returned to normal by 48 h. Elimination of radioactivity was very slow, with less than 0.5% of the dose in the urine up to 7 days after dosing, and 23-26% in the faeces (more than half of which appeared in the first 24 h). Most of the administered radioactivity (74-76%) was retained 7 days after dosing. Approximately half of the dose was in the liver; it was eliminated with a halflife of 220 days. At 48 h after dosing, most of the hepatic radioactivity comprised unchanged flocoumafen. Treatments of flocoumafen-dosed rats with warfarin or with cytochrome P450-inducing doses of phenobarbitone were without effect on the hepatic residue of flocoumafen.  相似文献   

18.
[14C]Flamprop-methyl administered orally to rats (3-4 mg kg?1 body weight) was excreted mostly via the faeces (78.7 and 61.6% in males and females, respectively). Elimination was rapid and 90% of the dose of 14C was excreted in faeces and urine 0-48 h after dosing. The distribution of 14C between faeces and urine was different in males and females. No expired [14C]carbon dioxide was detected and less than 2% of the dose remained in the animals 4 days after dosing. The predominant metabolic pathway was hydrolysis of the ester bond to afford the carboxylic acid which was excreted unchanged and as its glucuronide conjugate. Aromatic hydroxylation occurred at the para- and meta-positions of the N-benzoyl ring. N-(3)-Chloro- 4-fluorophenyl-N-(3,4-dihydroxybenzoyl)-DL -alaninate was also formed. This hydroxylated form of flamprop-methyl was partially O-methylated at the 3-hydroxy group. Flamprop-methyl was also metabolised and eliminated rapidly by dogs, mice and rabbits. The last of these three species afforded very little aromatic hydroxylation and also differed from the others in that the metabolites were eliminated mostly in the urine. Aromatic hydroxylation lay in the order: male rat = female rat > dog= mouse>rabbit (female).  相似文献   

19.
A goat was dosed orally with [14C]tefluthrin, twice daily for 4 days, at a rate equivalent to 10.9 mg kg?1 in its diet. Within 16 h of the final dose, 70.1% of the dose had been excreted (urine 41.4%, faeces 28.7%). Extensive metabolism occurred in the goat by ester cleavage and oxidation at a variety of positions on the molecule. Low radioactive residues were detected in the milk (0.076 mg kg?1), fat (0.076 mg kg?1) and muscle (0.016 mg kg?1), with tefluthrin as the largest individual component of the residue (milk 66.5%, fat 76.7%, muscle 34.2%). Higher residues were present in the kidney (0.3 mg kg?1) and liver (1.0 mg kg?1) and only a small percentage of this residue was due to tefluthrin (kidney 3.4%, liver 6.1%). The remainder of the residue in the kidney and liver was a complex mixture of metabolites. Most of the kidney metabolites were identified, but a high proportion of the liver residue was due to six unidentified polar compounds.  相似文献   

20.
Endosulfan residues on alfalfa hay exposed to drying by sunlight, ultraviolet light and air under controlled conditions were investigated using g.l.c. and t.l.c. Maximum loss of total endosulfan and related residues calculated as endosulfan occurred approximately 7 days after application and exposure on Lot 1 (dark) and 5 days on Lot II (ultraviolet light) and 6 days on Lot III (sunlight). Maximum losses of residues on Lot I, Lot II and Lot HI were 48.3, 66.7 and 81.9%, respectively. No endosulfan lactone was detected in any of the samples exposed to the different light treatments. In all Lots the endosulfan sulphate percentage of the total residue increased but most dramatically in the dark drying experiment. The endosulfan a-hydroxy ether residues increased in Lot III (sunlight) up to day 7.  相似文献   

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