摘要:

Lentil grains treated with malathion and stored under laboratory conditions for 12 months formed bound residues. Bioavailability and the effects of lentil‐bound residues of malathion in rats were studied. The amount of bound residues in lentils treated with14C‐malathion at 10 ppm and 50 ppm gradually increased to 9.52% and 13.01% of the initially applied doses after 12 months. When rats were fed these14C‐bound residues, radioactivity excreted in urine accounted for 34.49% of the administered dose. In feces, 26.15% of given dose was methanol‐extractable while 18.67% was determined as nonextractable. Various tissues including liver, kidney, fat and lungs contained 8.93% while radioactivity in expired air (14CO2) was low (1.51%). The results indicate that lentil‐bound malathion residues are highly bioavailable to rats. Analysis of the lentil material containing bound residues indicated that the main compound was malathion.

ISSN:0360-1234    

DOI:10.1080/03601239209372783

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Under conditions of local practice, the application of 2,3‐succinate‐14C‐malathion on beans led to the formation of 17–18% of bound14C‐ residues after 30 weeks. When fed to rats, 75% of these residues became bioavailable after 2 days with the major part, excreted via expired air (8%) and urine (60%). The main radioactive metabolites detected in urine were malathion monocarboxylic acid and malathion dicarboxylic acid. Feeding of bound residues to mice (1.8 ppm in feed) for 90 days resulted in a reduction in body weight gain after 60 days and inhibition of erythrocyte cholinesterase activity after 90 days. Increased levels of serum glutamic oxaloacetic transaminase and alkaline phosphatase were also observed. The results strongly suggest that bean‐bound malathion residues can cause adverse biological effects in mice.

ISSN:0360-1234    

DOI:10.1080/03601239209372784

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Paddy (unmilled rice), milled rice and maize‐bound14C residues were prepared using14C‐succinate‐labelled malathion at 10 and 152 ppm. After 3 months, the bound residues accounted for 12%, 6.5% and 17.7% of the applied dose in paddy, milled rice and maize respectively in the grains treated at 10 ppm. The corresponding values for the 152 ppm were 16.6%, 8.5% and 18.8%. Rats fed milled rice ‐ bound14C‐residues eliminated 61% of the14C in the faeces and 28% in the urine. The corresponding percentages for paddy and maize were 72%, 9% and 53%, 41% respectively; indicating that bound residues from milled rice and maize were moderately bioavailable. When rice‐bound malathion residues (0.65 ppm in feed) were administered to rats in a 5 week feeding study, no signs of toxicity were observed. Plasma and RBC cholinesterase activities were slightly inhibited: blood urea nitrogen was significantly elevated in the test animals. Other parameters examined showed no or marginal changes.

ISSN:0360-1234    

DOI:10.1080/03601239209372785

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Stored wheat treated with radiolabelled pirimiphos‐methyl (0–2‐diethylamino‐6‐methyl‐pyrimidin‐4‐yl 0,0‐dimethyl phosphorothioate) formed bound (nonextractable)14C residues. Supercritical fluid extraction, gas chromatography and mass spectrometric techniques were used to identify and quantitate the14C bound residues in wheat grains. The amount of bound14C residues present after 28 weeks of storage was about 9.9% of the applied radioactivity. Pirimiphos‐methyl accounted for 80% of the bound residue. Grain‐bound residues were fed to rats for 5 days. After a total period of 8 days a substantially large percentage of the administered bound14C residues (72.9%) was eliminated in urine while feces contained only 17.9%. Bound pirimiphos‐methyl in wheat grain was metabolized in rats by processes involving hydrolysis,N‐dealkylation and O‐demethylation. The results indicate that wheat‐bound residues of pirimiphos‐methyl are highly bioavailable to the rat and may possess a toxicological potential as manifested by a significant reduction in body weight gain.

ISSN:0360-1234    

DOI:10.1080/03601239209372786

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Wheat grains were treated with14C‐pirimiphos‐methyl to generate bound residues for testing their bioavailability to rats. Bound residues accounted for 25% of the applied dose (50 ppm) at the end of one year. When the grain bound residues were fed to rats for 48 hours the animals eliminated 30 and 40% of the administered dose in urine and feces respectively, after 5 days. Radioactivity in some selected organs and blood accounted for 37% of the administered dose after 2 days, which gradually declined to17.after 5 days. These data indicate that wheat‐bound pirimiphos‐methyl residues are moderately bioavailable to rats. In a 90‐day feeding study, inhibition of plasma cholinesterase and brain acetylcholinesterase strongly suggest that the bound residues possess a toxicological potential.

ISSN:0360-1234    

DOI:10.1080/03601239209372787

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Using a14C‐labelled pirimiphos‐methyl preparation, the percentage of pirimiphos‐methyl residues bound to maize grains after 32 weeks of storage was 13% of the applied dosage, or 38% of total terminal residues. Evidence is presented to show that bound residues of pirimiphos‐methyl are bioavailable to the rat: 30%, 2% and approx. 6% of radioactivity were measured in urine expired air, and some organs respectively. A major portion of radioactivity (55%) was eliminated through faeces. Grain‐bound pirimiphos‐methyl residues (generated after storing whole maize grains with pirimiphos‐methyl at concentrations of 10 ppm and 100 ppm) were administered to albino rats for 12 weeks. Body and organ weights, enzyme activities and blood chemistry were tested. There was a significant reduction in body weight gain in female rats. Also a significant reduction in blood cholinesterase activity was observed in both male and female rats fed on grain bound pirimiphos‐methyl residues at two dose levels. The white blood cell count increased significantly in male rats fed on the high dose. No significant changes were observed in the other blood chemistry parameters tested. The results indicate that maize‐bound pirimiphos‐methyl residues can exert adverse biological effects in the rat.

ISSN:0360-1234    

DOI:10.1080/03601239209372788

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Wheat grain was treated with14C‐chlorpyrifos‐methyl to generate bound residues for determining their bioavailability to rats. In a parallel experiment, bound residues were prepared with non‐labelled chlorpyrifos‐methyl to determine possible adverse effects in rats fed the grain‐bound residue for 28 and 90 days. Two dose levels of 10 and 50 ppm were initially used on the grain.

ISSN:0360-1234    

DOI:10.1080/03601239209372789

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

14C‐carbofuran penetrated readily into seeds ofVicia fabaand the rate of penetration was found to be dose dependent. The percentage of bound residues was generally low and did not exceed 3% of the applied dose. When the bound residues were fed to rats 46% of the radioactivity was eliminated via CO2and urine, while tissues contained 25%. Carbofuran phenol and 3‐hydroxy carbofuran represented the main metabolites in the urine. These data indicate that bean‐bound carbofuran residues are highly bioavailable to rats. Feeding mice with bound carbofuran residues for 90 days led to inhibition of erythrocyte cholinesterase activity after 30 days (35–40%) while the plasma enzyme remained unaffected. Serum transaminases and blood urea nitrogen were significantly elevated, indicating injury to hepatic and renal structures. The results strongly suggest that the bound residues can induce adverse biological effects in mice.

ISSN:0360-1234    

DOI:10.1080/03601239209372790

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Fumigation ofVicia fabaseeds with14C‐methyl bromide for two weeks followed by four‐week aeriation period resulted in the formation of bound residues equivalent to 33% of the terminal residue or approx. 30 ppm. Of this amount, 3.4% was incorporated into the seed DNA. The effect of cooking on the treated‐aerated beans showed that 50% of the initial dose remained bound to seed tissues. A bioavailability study of14C‐bound residues showed that over 70% of the ingested dose was bioavailable to the rat. The major radioactivity was eliminated in urine (36.6%), feces (24.1%) and CO2(19.3%). Analysis of the urine showed that 36% of the radioactivity was in the purine fraction; one fifth of this amount was associated with 7‐14C‐methylguanine. Subacute feeding of bound residues to mice for 8 weeks at a dietary level of 30 ppm resulted in a significant decrease in the number of white blood cells and an increase in the activity of SGOT and SGPT of the treated mice. Blood urea nitrogen was also increased while blood creatinine remained unaltered.

ISSN:0360-1234    

DOI:10.1080/03601239209372791

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Stored wheat treated with14C‐chlorpyrifos‐methyl and14C‐malathion has been shown to contain residues which are not extractable by conventional analytical procedures. Grain containing such residues was bioassayed using the stored product insect T. castaneum. There was no effect on the insects in the tests involving the non‐extractable residues of malathion, but there was a significant reduction in the number of adults reaching maturity on chlorpyrifos‐methyl treated extracted grain. This effect could be associated with the trichloropyridinol metabolite of chlorpyrifos‐methyl which has been shown to comprise 60% of the non‐extractable residue.

ISSN:0360-1234    

DOI:10.1080/03601239209372792

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor