摘要:

Wheat grain was treated with radiolabeled fenvalerate and stored for various periods; up to 6 months. The grain was surface washed, Soxhlet‐extracted with methanol, and the residue determined. A relative constant amount of bound residues (6%), i.e., non‐extractable radioactivity, was found 2 months after application and remained constant. Seventy‐eight percent of the extractable radioactivity in grain after 6 months was identified as fenvalerate. When bound residues were fed to rats, 40% of the administered dose was eliminated through the urine and the remainder through the feces within 90 h. Approximately a third of the radioactivity excreted in the urine and feces was intact fenvalerate. Feeding bound residues to fathead minnows at a subchronic dose resulted in a time‐dependent mortality of 40% of the fish after 6 days exposure.

ISSN:0360-1234    

DOI:10.1080/03601239209372776

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Lactating dairy cows were fed deltamethrin (2 or 10 mg kg‐1feed) for 28 consecutive days and deltamethrin residues measured in milk and tissues. Deltamethrin residues were higher relative to dose administered. The order of relative concentrations of deltamethrin in tissues, measured 1, 4, and 9 days after the last dose was: renal fat > subcutaneous fat > fore‐quarter muscle > hindquarter muscle > liver > kidney. Depletion of deltamethrin residues in milk was very rapid indicationg the half‐life of the insectide of about 1 day. Trace amounts of deltamethrin metabolites 3‐ (2,2‐dibromovmyl)‐2,2‐dimethylcyclopropane carboxylic acid (< 0.0235 ppm) and 3‐phenoxybenzoic acid (< 0.034 ppm) were also detected in milk and tissues of treated cows.

ISSN:0360-1234    

DOI:10.1080/03601239209372777

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The minimum criterion routinely used for qualitative analysis, i.e. the known and unknown chemicals having the same GC retention time (RT) on two dissimilar columns using a specific detector, or having the same RT on one column and similar responses to two specific detectors, or having the same RT on one column and two masses on a mass spectrometer run in selected ion monitoring (SIM) mode may not be adequate for atrazine and deethylatrazine confirmation. Current work in this laboratory has shown that atrazine and tris(2‐chloroethyl) phosphate, a flame retardant and plasticizer in many products, have the same RT on capillary dimethylsiloxane and diphenyldimethylsiloxane columns. Both chemicals have similar responses to electron capture and nitrogen/phosphorous detectors. Also, deethylatrazine and prynachlor have the same retention times on nonpolar capillary columns. Prynachlor also fragments into the three ions that are used routinely for deethylatrazine confirmation using selected ion monitoring with a mass spectrometer. While the potential exists for false positives or negatives for atrazine or deethylatrazine in soil and water, appropriate Chromatographic and confirmatory techniques will avoid potential problems.

ISSN:0360-1234    

DOI:10.1080/03601239209372778

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The haematotoxicity of technical hexachlorocyclohexane (HCH) (1000 ppm) was investigated in male albino rats fed with diet free of vitamin A or containing vitamin A at 2000 or 105I.U./kg. Assesment of HCH‐induced haematotoxicity at the end of the 7 weeks feeding period was done on the basis of haemoglobin content, total count of red blood cells and white blood cells and the differential counts of the white blood cells as well as by parameters such as packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin content, prothrombin time and clotting time. In the rats fed with vitamin ?‐free diet containing HCH, significant reductions were noticed in the total white blood cells count, clotting time and prothrombin time indicating severe haematotoxicity. Differential count of the white blood cells of these rats revealed a non‐significant reduction in the lymphocyte count. The only indication of haematotoxicity caused by hexachlorocyclohexane in the vitamin A supplemented rats was a slight but statistically significant reduction of the total count of white blood cells. These results demonstrate that the haematotoxicity of hexachlorocyclohexane in the rats is enhanced by vitamin A‐deficiency and its supplementation particularly in excess but not at hypervitaminotic level is protective against the toxicity.

ISSN:0360-1234    

DOI:10.1080/03601239209372779

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The efficiency of three methods of treatment including activated carbon, reverse osmosis and deionisation was investigated for removal of atrazine from water. At the beginning of the cycle of treatment the water was artificially contaminated with 10 μg.1‐1of atrazine which is five times the maximum permitted level for drinking water. At the end of the cycle atrazine was measured by means of immunoenzymology. The results showed that a) reverse osmosis gives appreciable but limited results, b) deionisation results in the total retention of atrazine, but it was not retained indefinitely and c) the eight types of activated carbon tested presented different patterns of behaviour, however one type showed an excellent capacity for retention.

ISSN:0360-1234    

DOI:10.1080/03601239209372780

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The catalytic degradation of chlorfenvinphos and méthidathion on H+, Ca+2, Na+and ?+monoionic kaolinite and bentonite was investigated. The results showed that the decomposition of chlorfenvinphos was greater than methidathion in both clays. The extent of degradation was influenced by the nature of the exchange cations and its degree hydration, in the following sequence: K+>Na+>Ca+2>H+/A1+3. In both clays the process of hydrolysis occurred in two stages involving first‐order kinetics of differents hydrolysis rates. The first stage consisted a high hydrolysis rate of short duration and the second had a slow rate but involved a continuous hydrolysis.

ISSN:0360-1234    

DOI:10.1080/03601239209372781

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The pharmacokinetics and anticholinesterase properties of a single oral dose 6mg/Kg of technical phenamiphos [ethyl 4‐(methylthio)‐m‐tolyl isopropylphosphoramidate] were investigated in male rats. Animals were killed at each time intervals of 0.5, 1.0, 1.5, 3, 6, 12, 24, 48, and 72 hrs after dosing. The total recovered amount of phenamiphos from brain and plasma tissues reached high level at the first time interval and disappeared biexponentially from both tissues to low level at the end of the experiment. Brain tissue has a greater affinity to phenamiphos than plasma tissue. The half‐ life of the elimination of phenamiphos from brain and plasma were 100 and 212 hr corresponding to the rate constant values of 0.01 and 0.003 hr‐1, respectively. Plasma AUC (area under the curve) value was 1239.81 ug hr/L, explaining there was no tendency for the compound to accumulate in the brain tissue (AUC = 774.38 ug hr/Kg) compared to the plasma. On the other hand, determination of cholinesterase activity showed that, phenamiphos inhibited the enzymes in both brain and plasma, where the depression of ChE activity was usually more marked in plasma than in brain.

ISSN:0360-1234    

DOI:10.1080/03601239209372782

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor