bluuebunny/crossref_metadata_2025_split huggingface dataset:
Excretion and residues of the pyrethroid insecticide cypermethrin in laying hens
Authors: Hutson David H. , Stoydin George 
Published: November 2006

AbstractLaying hens were treated daily for 14 days with oral doses of [14C‐phenoxy]cypermethrin (1.52 mg day−1, 0‐7 mg kg−1) formulated on a small quantity of diet. Radioactivity in the eggs reached a plateau value of 0.05 μg equivalents g−1 8 days after the start of dosing. Most of the residue was found in the yolk and was a mixture of cypermethrin and material which was closely associated with neutral lipids and phosphatidyl cholines. Four and a half hours after the last dose, the birds were killed and selected tissues were taken for analysis. The highest residue was found in the liver. This was composed of cypermethrin and a mixture of very polar metabolites which were not hydrolysed to significant amounts of 3‐phenoxybenzoic acid or its 4‐hydroxy derivative.
Analytical method for the simultaneous determination of diquat and paraquat residues in potatoes by high‐pressure liquid chromatography
Authors: Worobey Brian L. 
Published: November 2006

AbstractA novel method was developed for the simultaneous determination of diquat and paraquat residues in potatoes. Potato tissues were spiked at several levels and extracted with acid using a micro‐reflux procedure with 5 g of sample; this was followed by adjusting the hydrolyzate pH to 9 to 10 and using a silica Sep‐Pak for rapid clean‐up and preconcentration. Aliquots of the final eluate were taken to dryness, dissolved in the h.p.l.c. mobile phase and analyzed as their heptanesulfonate ion‐pairs by u.v.‐h.p.l.c. (reverse phase column chromatography) at 254 and 313 nm for paraquat and diquat, respectively. A detection limit of approximately 0.05 mg kg−1 dication in a 5‐g sample of spiked potato (i.e. 0.25 μg ml−1 final extract) was achieved. Recoveries of 79.5 to 97.6% were obtained at spiking levels of 0.05 to 5.0 mg kg−1 for diquat and paraquat with coefficients of variation not greater than 8.27%. The method was developed and validated using 14C‐radiolabelled diquat and paraquat; u.v.‐h.p.l.c. recoveries were comparable with recoveries determined by radioassay. Several parameters affecting the extraction, adsorption and chromatography of diquat and paraquat were evaluated. The formula weights of diquat and paraquat were determined and their importance described; they were determined as mono‐ and tetra‐hydrates, respectively.
Studies into the action of the diphenyl ether herbicides acifluorfen and oxyfluorfen. Part I: Activation by light and oxygen in leaf tissue
Authors: Gillham David J. , Dodge Alan D. 
Published: November 2006

AbstractThe effect of acifluorfen and oxyfluorfen on chlorophyll bleaching, lipid peroxidation and photosynthesis in pea leaf discs was studied. Both her‐ bicides induced light‐dependent bleaching and lipid peroxidation, the level of damage being greater at higher light intensities. Photosynthetic carbon dioxide fixation was only partially inhibited in treated leaf discs incubated in darkness, thus indicating that these herbicides did not inhibit photo‐ synthesis as a primary mode of action. Leaf discs maintained in darkness showed no visible signs of injury, and light‐dependent herbicide‐induced damage was reduced by incubating discs under nitrogen, orpre‐incubating them with the electron‐transport inhibitor monuron. It is suggested that acifluorfen and oxyfluorfen are activated by a light‐dependent process, which requires photosynthetic electron transport.
The determination of the herbicide dinoseb in lentils
Authors: Cessna Allan J. 
Published: November 2006

AbstractResidues of the herbicide dinoseb were determined gas chromatographically in lentils which had been treated at two locations in Saskatchewan with post‐emergence applications of dinoseb at 1.4 and 1.7 kg ha−1. Herbicide residues, determined at selected times after application, were not detected at the limit of detection of the analytical method (0.05 mg kg−1) in either the seed and straw at maturity, or in the green foliage six to eight weeks after application. Recoveries of dinoseb were 76% from fortified green foliage at the 0.1 mg kg−1 level, and 64% from fortified seed at the 0.05 mg kg−1 level.
The effect of grain moisture on the biological activity of fenitrothion residues on maize in storage
Authors: Samson Peter R. , Bengston Mervyn , Parker Russell J. , Keating Julie A. 
Published: November 2006

AbstractThe biological activity of freshly‐applied fenitrothion on maize at a range of moisture contents was measured using adults of several species of Coleoptera. Activity declined by about ×15 as grain moisture increased from 10 to 24%, the greatest change occurring at moisture contents above about 14%. This occurred regardless of whether the grain was treated with fenitrothion when already moist or was moistened after treatment, and it was not reversed by drying the treated grain. These differences in activity could not be explained by differences in the chemical residues. The suggested mechanism is a reduction in the availability of fenitrothion for pick‐up by insects.
sublethal neurotoxic effects of the fungicide benomyl on earthworms (Eisenia fetida)
Authors: Drewes Charles D. , Zoran Mark J. , Callahan Clarence A. 
Published: November 2006

AbstractEarthworms Eisenia fetida were treated by surface contact exposure for 4 days with the fungicide benomyl. Non‐invasive electrophysiological recordings after treatment with sublethal concentrations of 0.2‐25 mg benomyl litre−1 of water (=0.003−0.435 μg benomyl cm−2 of filter paper) indicated concentration‐dependent decreases in conduction velocity for the medial and lateral giant nerve fibres. Threshold concentration for these effects was approximately two orders of magnitude less than the LC50. The effects on velocity were not accompanied by alterations in refractory period or impairment of locomotory reflexes, but persisted for at least several weeks after treatment. Morphometric analysis of treated animals revealed a disruption of the myelin‐like sheath surrounding giant fibres but no change in fibre diameters.It is concluded that benomyl had subtle and sublethal neurotoxic effects on earthworm giant nerve fibres. The data indicate that giant fibre conduction velocity is a particularly sensitive parameter for detecting these effects in intact worms.
Fate of a water‐soluble herbicide spray on foliage: Part I. Spray efficiency: Measurement of initial deposition and absorption
Authors: Don Wauchope R. , Streeth Joe E. 
Published: November 2006

AbstractMSMA (monosodium methylarsonate) is non‐volatile and degrades in the environment to arsenic species which can be determined at the nanogram level. It is thus an excellent tracer for the study of the efficiency of deposition (defined as the fraction of material sprayed that deposits on target foliage) and subsequent fate of a water‐soluble pesticide applied to foliage. MSMA was applied to rice (Oryza sativa L. cv. Labelle) foliage at two rates and at various stages of growth. After spraying the foliage was sampled and analysed for surface (removable by water‐washing) and absorbed MSMA. Absorption of MSMA was so rapid that within the two hours between application and washing nearly one‐half of the recovered MSMA became unavailable for wash‐off. The total amounts of MSMA recovered were approximately proportional to plant size and application rate. When the rice foliage reached approximately 80 cm in height, the canopy closure (ground cover) was complete; nevertheless, only about 50% of the sprayed MSMA was found on and in the plants. As the rice canopy approached maturity, or approximately 130 cm high, complete interception of the spray occurred. These results indicate that canopy volume rather than ground cover was more important in determining the efficiency of spray deposition in this case, and that deposition efficiency may approach 100% with non‐volatile active ingredients.
Fate of a water‐soluble herbicide spray on foliage. Part Ii. Absorption and dissipation of foliar msma deposits: Mathematical modelling
Authors: Don Wauchope R. , Street Joe E. 
Published: November 2006

AbstractMSMA (monosodium methylarsonate) was applied to rice (Oryza sativa L. cv. ‘Labelle’) plants at weekly intervals from the time the plants were 46 cm high until heading. Each application was to a different set of plants. The sprayed plant tops were analysed for MSMA immediately after spraying and at weekly intervals thereafter until heading. MSMA deposits became completely absorbed after one week and then the total residues declined exponentially to background levels with a half‐life of about 15 days. Plant stunting effects depended on the amount of MSMA applied and the rate of growth at the time of application. Sterilisation effects depended on the amount of MSMA applied and the proximity in time of the application to panicle initiation. A mathematical model of the data showed that sterility symptoms were consistent with calculated MSMA concentration in tissue at the time of panicle initiation.
Synergistic effects of agonists and antagonists in insect venoms—a natural way of insecticidal action
Authors: Piek Tom 
Published: November 2006

AbstractContrary to the typical killing action of most animal venoms, including social wasp venoms, the solitary wasp venoms seem to have been created to paralyse the prey. This suggests a specific action on parts of the nervous system. However, the solitary wasp venoms studied, contain many agonists and antagonists of synaptic transmission, and their paralysing action is very complicated. Besides a contribution of agonists to initiate and enhance the action of antagonists, one of the venoms contains two antagonists with different actions, and one of these antagonists enhances the effect of the other. The specific action of both toxins and their interaction will be discussed as an example of how nature enhances pesticide action through mixtures.
Extended summaries: Physicochemical and biophysical panel symposium enhancing pesticide action through mixtures
Authors: Gillard Grace 
Published: November 2006

AbstractThe following are summaries of papers presented at a meeting of the Physicochemical and Biophysical Panel of the Pesticides Group held on 14 October 1986 at the Society of Chemical Industry, 14 Belgrave Square, London SWIX8PS. The papers published here are entirely the responsibility of the authors and do not reflect the views of the Editorial Board of Pesticide Science.
Biochemical and toxicological differences in the modes of action of the benzoylureas
Authors: Neumann Rainer , Guyer Walter 
Published: November 2006

AbstractThe two insecticidal benzoylurea compounds, diflubenzuron and chlorfluazuron, show large differences in their toxicity against the larvae of insects like the tobacco budworm, Heliothis virescens, or the Egyptian cotton leafworm, Spodoptera littoralis, chlorfluazuron being about 100 times more toxic. This difference is due mainly to a much faster metabolism of diflubenzuron. Its half‐life within the larvae is about 5 h, compared to about 50 h for chlorfluazuron. Chlorfluazuron is also the much better ovicide of the two, following injection of the compounds into the females of H. virescens. Again the difference in the rate of metabolism is the main cause. The rate of excretion of the parent benzoylureas is relatively low, but their metabolites are excreted very quickly.
Genetic effects of phthalimide fungicides on diploid Aspergillus nidulans
Authors: Ziogas Basil N. , Georgopoulos Spyros G. 
Published: November 2006

AbstractA few specimens of ‘Ridomil 25 WP’, a commercial formulation of metalaxyl, showed high genetic activity on a heterozygous diploid strain of Aspergillus nidulans. This activity was due to an impurity which was identified by mass and n.m.r. spectroscopy as captafol. This and the related fungicides captan, dichlofluanid, and tolyfluanid greatly increased the yield of euploid colour segregants from the diploid strain. At low captafol concentrations, most of the induced segregants resulted from mitotic crossing over but chromosome non‐disjunction or loss was also caused at high concentrations. Mitotic crossing over could be induced also by vapour‐phase action of captafol and captan. The mechanism by which these phthalimides may exert their genetic effects is discussed.
Dislodgeable residues and persistence of diazinon, chlorpyrifos and isofenphos following their application to turfgrass
Authors: Sears Mark K. , Bowhey Cindy , Braun Heinz , Stephenson Gerald R. 
Published: November 2006

AbstractIn laboratory experiments, residues of diazinon applied to turfgrass, Poa pratensis L., that could be dislodged by rubbing with cheese‐cloth, declined from c. 10% of the total applied when the grass was vigorously rubbed immediately after application to 0.3% after 1 day. Sunlight did not influence the rate of decline in dislodgeable residues or residues remaining on or within the leaf blades. In field experiments where 4.5 kg ha−1 of diazinon was applied in liquid or granular form, about 20 times more diazinon was dislodged from the liquid formulation immediately after application than from the granular. By 1 day after application the percentage of the total applied diazinon that could be dislodged was equal for both formulations. Rainfall had a significant effect on the amount dislodged from grass blades, but mowing did not. Similar rates of decline in the dislodgeable fraction of diazinon, chlorpyrifos and isofenphos were observed in field experiments. Recovery of the dislodgeable fraction declined to 0.25% or less of the total amount of any of these insecticides by 1 day after application. However, residues in the thatch remained sufficiently high for control of insects for up to 7 days after application for diazinon and 14 days for chlorpyrifos and isofenphos.
Assessment of the grain protectants chlorpyrifos‐methyl plus bioresmethrin, fenitrothion plus (1R)‐phenothrin, methacrifos and pirimiphos‐methyl plus carbaryl under practical conditions in Australia
Authors: Desmarchelier James , Bengston Mervyn , Davies Richard , Elder Brian , Hart Richard , Henning Ronald , Murray William , Ridley Edward , Ripp Eric , Sierakowski Charles , Sticka Rex , Snelson Jack , Wallbank Barry , Wilson Arnold 
Published: November 2006

AbstractMethacrifos (22.5 g t−1) and the three protectant combinations chlorpyrifos‐methyl (10 g t−1) plus bioresmethrin (1 g t−1), fenitrothion (12 g t−1) plus (1R)‐phenothrin (2 g t−1) and pirimiphos‐methyl (4 g t−1) plus carbaryl (8 g t−1) were each applied to grain that was stored in at least 15 silos. Grain temperature and levels of protectant were regularly monitored, and samples from 12 storages using each treatment were taken for laboratory assays against Rhyzopertha dominica and Tribolium castaneum. Grain condition did not deteriorate during storage. Grain remained free of insects in 60 of the 63 storages treated; partial failure in the other 3 storages was attributed to low or irregular levels of protectant. The mean and range of residue values of all protectants were recorded as a function of time and the mean observed values corresponded to predicted values. In laboratory bioassay, the order of effectiveness against T. castaneum was methacrifos > chlorpyrifos‐methyl plus bioresmethrin > fenitrothion plus (1R)‐phenothrin = pirimiphos‐methyl plus carbaryl. The order of effectiveness against R. dominica was carbaryl plus pirimiphos‐methyl = (1R)‐phenothrin plus fenitrothion > methacrifos > bioresmethrin plus chlorpyrifos‐methyl.
A comparison of cypermethrin distribution on cattle hair after application of impregnated ear and tail tags
Authors: Taylor Stuart M. , Elliott Christopher T. , Blanchflower William J. 
Published: November 2006

AbstractTen dairy cows were separated into two groups of five. One group was ear tagged with a PVC ear tag containing 8‐5 g kg−1 cypermethrin in each ear. A PVC strip impregnated with the same quantity of cypermethrin was attached to the tail of each cow in the other group. The concentration of cypermethrin in hair samples from the neck, flanks and the anterior, sides and the posterior of the udder was measured for a period of 10 weeks after application. Concentrations were found to be high in those body areas nearest to the points of application, moderate on the flanks but low on the front and sides of the udder.
Contaminant and formulation analysis of MSMA using high‐pressure liquid chromatography — graphite furnace atomic absorption spectrophotometry
Authors: Pick Frans E. , De Beer Pieter R. , Prinsloo Susan M. , Van Dyk Louis P. 
Published: November 2006

AbstractHigh‐pressure liquid chromatography with an ion‐exchange column combined with graphite furnace atomic absorption spectrometry was used to analyse commercial formulations of sodium hydrogen methylarsonate (MSMA). No arsenite or arsenate salts or dimethylarsinic acid were detected as contaminants in the formulations, and the MSMA concentrations were found to be in accordance with the concentrations given on the containers.
Hydrosoil residues and Hydrilla verticillata control in a central florida lake using fluridone
Authors: Schmitz Don C. , Leslie Andrew J. , Nall Larry E. , Osborne John A. 
Published: November 2006

AbstractFluridone was applied to a 98‐8‐ha lake in Orange County, Florida, USA, in five different treatment plots between October 1982 and February 1983 to control a severe infestation of Hydrilla verticillata. Hydrosoil residues and submersed aquatic plant biomass were monitored within the lake. Fluridone did not affect the submersed vegetation during the 4‐month fall‐winter treatment period. As water temperatures increased during spring, Hydrilla biomass declined at an average of 0.178 kg m−2 per month. By summer (192 days after last treatment), the target species could not be found within the lake. Fluridone residues were detected in the hydrosoil immediately following treatments and generally peaked coinciding with the decline in aquatic plant biomass. The maximum fluridone detected in the hydrosoil was only 5% of the 2.25 kg ha−1 applied, and this amount was obtained from outside of a treatment area. Residue concentrations were highly variable between sampling sites and sampling periods and unexpectedly increased 14 months after treatment. Winter‐killed marginal vegetation is a possible source of this increase. Detectable concentrations of fluridone, and vegetation control, persisted for a total of 86 weeks from the date of the last treatment and non‐detectable residues may have persisted after 86 weeks. This study indicates that a lower application rate might have provided adequate control of Hydrilla and possibly decreased residue concentrations in non‐target areas.
The physical and chemical properties of the herbicide cinmethylin (SD 95481)
Authors: Grayson B. Terence , Williams Karen S. , Freehauf Paul A. , Pease Rodney R. , Ziesel William T. , Sereno Richard L. , Reinsfelder Ronald E. 
Published: November 2006

AbstractCinmethylin (SD 95481), is a novel herbicide developed for the selective pre‐emergence control of many annual grass weeds in a wide range of temperate and tropical crops. Representing new herbicide chemistry, cinmethylin is in the cineole family.Cinmethylin is a mobile colourless liquid with a boiling point of 313°C under an inert atmosphere at atmospheric pressure. It has a density of 1015 kg m−3 and a viscosity of 70–90 mPa s, both at 20°C. It is miscible in all proportions with most organic solvents but has a low solubility, 63 mg litre−1, in water. It has a vapour pressure of 10.2 mPa (20°C) and the vapour pressure/temperature relationship is given by loge P(Pa)=28.9–9816/T (K). The n‐octanol/water partition coefficient is 6850 and soil organic matter/water sorption coefficient (Kom) ranges between 165 and 235 over the three types of soil used in these studies.Cinmethylin is stable in water over the pH range 3–11. Solutions of cinmethylin in water or solvents are reasonably stable to sunlight, though thin films on a quartz surface photooxidise mainly to an ester within 24 h. This rate can be reduced by the addition of photostabilisers or by sorption onto soil surfaces. In an inert atmosphere cinmethylin is stable to high temperatures, though, in air, oxidation occurs at temperatures above 100°C to give the same product as by photodecay.
Chlorophyll sensitised photodegradation of 2‐dimethylamino‐5, 6‐dimethylpyrimidin‐4‐ol
Authors: Dixon Stephen R. , Wells Clifford H. J. 
Published: November 2006

AbstractThe chlorophyll sensitised photodegradation of 2‐dimethylamino‐5, 6‐dimethylpyrimidin‐4‐ol (I), a hydrolysis product of pirimicarb, in the solid state on silica gel and in chloroform solution has been investigated. The product distribution in the solid state photodegradation was different from that in chloroform solution and was dependent upon the wavelength range of the incident radiation. When radiation of wavelength greater than 420 nm was used, the products formed in the chlorophyll sensitised degradation of I in the solid state were similar to those obtained when Rose Bengal or Methylene Blue were used as sensitisers. These results indicate that singlet oxygen is implicated in the sensitised photodegradation of I in the solid state. Numerous products were formed in each of the systems studied.
Studies on the comparative effectiveness of permethrin and deet against bloodsucking arthropods
Authors: Buescher Michael D. , Rutledge Louis C. , Wirtz Robert A. 
Published: November 2006

AbstractA comparison was made of the effectiveness of permethrin and deet against Ornithodoros parkeri (Acari: Argasidae), Leptotrombidium fletcheri (Acari: Trombiculidae), Rhodnius prolixus (Heteroptera: Reduviidae), Phlebotomus papatasi and Lutzomyia longipalpis (Diptera: Psychodidae), Anopheles Stephensi, Anopheles albimanus, Aedes taeniorhynchus, Aedes aegypti and Culex pipiens (Diptera: Culicidae), Glossina morsitans (Diptera: Glossinidae) and Xenopsylla cheopis (Siphonaptera: Pulicidae), using dose‐response methods. At the ED95 (95% effective dose) level, deet was more potent (P<0.05) than permethrin against all species except O. parkeri and R. prolixus. In addition, the slope of the dose‐response line for deet was greater than that for permethrin against all species except O. parkeri and R. prolixus. Permethrin exhibited repellent and/or toxic effects, depending on the dose used and the individual tolerances of members of the insect test population.
Uptake, metabolism and effects of DDT, fenitrothion and chlorpyrifos on Tetrahymena pyriformis
Authors: Lal Sukanya , Saxena D. M. , Lal Rup 
Published: November 2006

AbstractThe uptake and metabolism of DDT, fenitrothion and chlorpyrifos were studied in cultures of the ciliate protozoan Tetrahymena pyriformis. When cultures were treated with DDT in concentrations varying from 0.01 to 0.5 μg ml−1, concentrations found in T. pyriformis were 3.8 to 335 μg g−1 dry weight. The accumulation of fenitrothion ranged from 28.7 μg g−1 in cultures treated with 1 μg ml−1 to 2260 μg g−1 in cultures treated with 10 μg ml−1. Under similar experimental conditions chlorpyrifos was accumulated from 24.7 to 15400 μg g−1. The patterns of uptake were dependent on the growth cycle, the ability of the organism to metabolise insecticide and the type of the insecticide used. Maximum accumulation of DDT, fenitrothion and chlorpyrifos occurred in 2, 4 and 6 h respectively. Tetrahymena metabolised DDT to DDD and DDE but failed to metabolise fenitrothion and chlorpyrifos.The effects on growth and morphology of T. pyriformis were studied over a period of 5 days. Higher concentrations (10, 50 and 100 μg ml−1) of DDT inhibited only the growth of the organisms and did not change cell morphology. Fenitrothion was extremely toxic to the organisms and at 5 and 10 μg ml−1 cells became more or less spherical and died after 48 h. However, concentrations of 0.5, 1 and 2.5 μg ml−1 fenitrothion caused growth inhibition, but only at 2.5 μg ml−1 was this permanent. Chlorpyrifos inhibited the growth of the organisms at 1, 5 and 10 μg ml−1 but the morphology was affected only at 5 and 10 μg ml−1.