scholarly journals Persistence of imidacloprid, acetamiprid and methomyl in qat leaves

2016 ◽  
Vol 9 (2) ◽  
pp. 51-59
Author(s):  
A.J. Al-Rajab ◽  
A.M. Alhababy ◽  
T. Alfaifi
Keyword(s):  
Liquid Chromatography ◽  
Daily Basis ◽  
Post Treatment ◽  
Application Rates ◽  
Maximum Residue Limits

SummaryQat leaves are chewed on a daily basis by approximately 10 million inhabitants of different countries. This study investigated the persistence of three insecticides most used in qat production, imidacloprid, acetamiprid and methomyl. These chemicals were applied separately on plots of ten qat trees each at the recommended application rates. Samples of qat leaves were collected separately at time 0 (1 h post-treatment) and 1, 3, 7, 12, 19, 26 and 37 days after application. The residues of the investigated pesticides were extracted and then quantified by liquid chromatography (LC-MS/MS). The half-lives of imidacloprid, acetamiprid and methomyl were 12.2, 11.7, and 5.1 days, respectively. Overall, our findings showed that imidacloprid and acetamiprid were more persistent than methomyl in qat leaves. Taking into account the maximum residue limits (MRL) in lettuce, due to lack of MRL in qat leaves, the residue concentrations were below MRL for imidacloprid 7 days after application, and 1 day after application for acetamiprid and methomyl.

scholarly journals Assessment of Insecticidal Properties of Products From Seeds of Carica papaya Against Callosobruchus Maculatus (Fabricius)

2018 ◽  
Vol 5 (4) ◽  
pp. 142
Author(s):  
Joy Ejemen Idoko ◽  
Bukola Mary Atere ◽  
Raphael Abiodun Adebayo
Keyword(s):  
Pest Management ◽  
Carica Papaya ◽  
Callosobruchus Maculatus ◽  
Adult Emergence ◽  
Adult Mortality ◽  
Post Treatment ◽  
Application Rates ◽  
Cowpea Seeds ◽  
Randomized Design ◽  
Papaya Seed

Powder and ash of Carica papaya seed extracted from riped and unriped C. papaya fruits obtained from Teaching and Research Farm of the Federal University of Technology, Akure were evaluated for their insecticidal potential against Callosobruchus maculatus (Fabricius) at application rates of 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0g per 20g of cowpea seeds. The experiment was carried out at the pest management laboratory of the Department of Crop, Soil and Pest Management under ambient laboratory conditions of 27±20C temperature and 70±5% relative humidity. Each treatment was infested with 5 pairs of C. maculatus. The experiment was laid out in Completely Randomized Design with each treatment replicated three times. Mortality of cowpea beetles were assessed at 24, 48 and 72hours post treatment. Thereafter data were collected on oviposition, adult emergence, weevil perforation index and seed germination. The results obtained indicated that adult mortality of C. maculatus increased with increasing application rates of powders and ashes of ripe and unripe C. papaya seeds. 100% mortality was observed on cowpea seeds treated with powders and ashes of unripe C. papaya seed at 0.8 and 1.0g application rates at 72hours post treatment. Powders and ashes of unripe C. papaya seed significantly reduced the oviposition potential of adult C. maculatus and caused significant reduction of damaged seeds. Highest number of seeds that germinated was recorded on the seeds treated with powders and ashes of unripe C. papaya seed at 0.8 and 1.0g application rates.

scholarly journals Measurement of tissue azithromycin levels in self-collected vaginal swabs post treatment using liquid chromatography and tandem mass spectrometry (LC-MS/MS)

PLoS ONE ◽  
2017 ◽  
Vol 12 (5) ◽  
pp. e0177615 ◽  
Author(s):  
Lenka A. Vodstrcil ◽  
Thusitha W. T. Rupasinghe ◽  
Fabian Y. S. Kong ◽  
Dedreia Tull ◽  
Karen Worthington ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Post Treatment ◽  
Tandem Mass ◽  
Vaginal Swabs

scholarly journals Determination of Imazaquin Residues in Soil by Solid-Phase Extraction and High-Performance Liquid Chromatography

2007 ◽  
Vol 90 (2) ◽  
pp. 568-574 ◽  
Author(s):  
Chen Xuyan ◽  
Hu Jiye ◽  
Li Jianzhong
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Solid Phase Extraction ◽  
High Performance ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Phase Extraction ◽  
Application Rates ◽  
Relative Standard ◽  
Strong Anion Exchange

Abstract A method has been developed for the quantitation of imazaquin residues in soil. The herbicide was extracted from soil with methanolwater (2 + 1, v/v) and cleaned up by strong anion-exchange solid-phase extraction cartridges. Analysis was performed by using high-performance liquid chromatography with ultraviolet detection. Average recoveries through the method ranged from 90.7 to 100.6%, with relative standard deviation equal to or lower than 6.6%. The limit of detection was estimated to be 0.0015 mg/kg, and the minimum quantitation concentration of imazaquin in soil was 0.005 mg/kg. This method was successfully applied to evaluate imazaquin residue levels in soil and its dissipation rates in a soybean field in the Xisanqi District of Beijing, People's Republic of China. The dissipation study showed that the half life of imazaquin in soil was 10.37 0.0135 days at 3 different application rates.

Dimethoate and fenthion as packing line treatments for tomatoes against Dacus tryoni (Froggatt)

1987 ◽  
Vol 27 (3) ◽  
pp. 465 ◽  
Author(s):  
NW Heather ◽  
PA Hargreaves ◽  
RJ Corcoran ◽  
KJ Melksham
Keyword(s):  
High Volume ◽  
Fruit Fly ◽  
Post Treatment ◽  
Maximum Residue Limits

Tomatoes were disinfested of Queensland fruit fly (Dacus tryoni) by using dimethoate or fenthion applied as sprays during grading and packing. Concentrations of 400 mg/L of either insecticide applied through a high-volume recirculatory flood system delivering 16 L/min.m2 were used to treat fruit moving at a speed of 0.5 m/min, on conveyor brushes, so that fruit was flooded for 10 s and remained fully wetted for a further 1 min. Treatment efficacies of 100% against 30 000 eggs and 30 000 larvae were obtained. The treatments were equally effective when used in conjunction with post-treatment cooling to 12.5�C for 1 week. No tainting problems were detected. Residues of dimethoate (also omethoate for selected samples) and fenthion in treated fruit were found to be less than the Australian Maximum Residue Limits for tomatoes at all times; methods for determination of fenthion and omethoate residues are described. These disinfestation treatments have advantages of automation and efficiency compared with previously proven dip treatments.

scholarly journals Residues of Fluvalinate and Permethrin on Flue-cured Tobacco

1986 ◽  
Vol 13 (4) ◽  
pp. 191-203 ◽  
Author(s):  
RB Leidy ◽  
TJ Sheets ◽  
LA Nelson
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Field Tests ◽  
Reverse Phase ◽  
Application Rates ◽  
Residue Levels ◽  
New Formulation

AbstractHigh-performance liquid chromatography (HPLC) with C18 reverse-phase columns was used to determine residues of fluvalinate and permethrin applied in the field to flue-cured tobacco in 1980 and 1981. Methods were developed to determine residue levels in both green and cured samples. In 1980 field tests, residues of fluvalinate applied at rates of 0.1 and 0.2 kg/ha averaged 3.3 and 7.2 ppm, respectively, on green tobacco harvested immediately after application, and declined to 0.3 and 2.7 ppm by 12 days after application. In 1981, with the same application rates, residues averaged 1.7 and 3.0 ppm (0 time) and declined to 0.4 and 0.5 ppm after 16 days, respectively. A new formulation of fluvalinate, applied at 0.06 and 0.01 kg/ha, averaged 0.9 and 1.3 ppm on day 0 and declined to 0.3 and 0.6 ppm after 16 days, respectively. Flue curing reduced fluvalinate residues approximately by 61 % both years. Immediately after application, residues of permethrin, applied at 0.2 kg/ha, averaged 9.6 ppm in 1980 and at application rates of 0.1 and 0.2 kg/ha averaged 3.5 and 3.8 ppm, respectively, in 1981. Residues declined to 7.0 ppm after 12 days in 1980 and to 3.2 and 3.5 ppm after 16 days in 1981. Losses of permethrin due to curing averaged 67 %.

scholarly journals Simultaneous Determination of Amphenicols and Metabolites in Animal-Derived Foods Using Ultrahigh-Performance Liquid Chromatography-Tandem Mass Spectrometry

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Xinyi Wu ◽  
Xixi Shen ◽  
Xiangyue Cao ◽  
Rongrong Nie ◽  
Haonan Zhang ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Poultry Meat ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Relative Standard ◽  
Maximum Residue Limits ◽  
Liquid Chromatography Tandem Mass ◽  
Ultrahigh Performance Liquid Chromatography

Amphenicols are widely used to prevent and treat animal diseases. However, amphenicol residues accumulate in livestock and poultry and harm consumers. We hypothesized that one can combine solid-phase extraction (SPE) with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) to simultaneously determine amphenicols and metabolites in pork, beef, lamb, chicken, and their products and meet government regulations for maximum residue limits. We extracted crude samples with ethyl acetate and ammonia water (98:2, v/v), purified the samples with a CNW Si SPE column, defatted the samples with acetonitrile-saturated n-hexane, and then determined the resulting analytes by UHPLC-MS/MS. The limit of detection of the analytes in livestock and poultry meat was 0.03–1.50 μg/kg, and the limit of quantification was 0.05–5.00 μg/kg. Measured chloramphenicol, thiamphenicol, and florfenicol concentrations were linear over the range 0.50–50 μg/kg; and the florfenicol amine concentration was linear over the range 5.00–200 μg/kg (all with correlation coefficients >0.9990). The recovery of the spiked samples was between 72% and 120%. The intraday relative standard deviation (RSD) ranged from 1% to 9%, and the interday RSD ranged from 1% to 12%. Based on the above results, the current method is sensitive, accurate, and reproducible with the detection limits being well below the maximum residue limits as per Chinese standard GB 31650-2019, and thus, our research hypothesis could be confirmed.

scholarly journals Evaluation of Some Pesticide Residues in Fruits import by High Performance Liquid Chromatography

2017 ◽  
Vol 27 (4) ◽  
Author(s):  
Lamees M. A. Salman ◽  
Iyad Abdul-Muhsan Ahmed
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Pesticide Residues ◽  
High Performance ◽  
Fruits And Vegetables ◽  
Current Knowledge ◽  
Maximum Residue Limits ◽  
Exposure Risks ◽  
Core Mixture

Pesticide residues have been found in various fruits and vegetables.  This study collected 24 samples and reported a method based on High Performance Liquid Chromatography (HPLC). For determination of pesticide residues used in Some fruits which were collected from different markets of Baghdad city to make) 24)  samples from (peel , core, mixture) for each type of fruits markets as:  Oranges( Egypt , Africa), Pomegranate ( Egypt), Mango ( Kenya ), Pears (China),  Plum fruits ( Africa ) , Kiwi (Turkey ) .That detective of ( 5 ) different  pesticides (diazinon,  malathion, chlorpyrifos ,parathion  and cypermethrin). The results were detected of multi-residues of  pesticides on the fruit in ( peel , core , mixture ) may be in the limit of Maximum residue limits(MRL) or higher of it   . The pesticides detected that exceeding the limits are: cypermethrin  in Kiwi (peel, core and mixture)at(0.204,0.038, 0.537), in pomegranate detected in (peel and mixture) at (0.509,0.189) mg/kg , Diazinon detccted in Egyptian orange in (peel ,core and mixture) at (0.031,0.207, 0.099) mg/kg . Malathion and Parathion was not detected at any type of fruits and  that results was compared with codex of FAO/WHO(2013). That data is important to monitor residues in food and to fill gaps in current knowledge would be helpful in assessing human exposure risks from ingestion of contaminated Fruits Imported to our country.

scholarly journals Оптимізація аналітичного контролю залишкових кількостей фунгіцидів цифлуфенаміду та дифеноконазолу у воді

2018 ◽  
Author(s):  
P. V. Stavnichenko ◽  
A. M. Antonenko ◽  
O. P. Vavrinevych ◽  
A. V. Stetsenko ◽  
S. T. Omelchuk. ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Water Samples ◽  
Analytical Determination ◽  
Gas Liquid Chromatography ◽  
Ecological Significance ◽  
Application Rates ◽  
The Cost ◽  
New Compounds ◽  
Active Substances

Introduction. Annually, the assortment and application rates of pesticides are supplemented with new compounds of various chemical classes. Methods for the determination of active substances in water by the method of gas-liquid chromatography are known to provide for the determination of only one fungicide, which is quite costly. Therefore, it remains an actual goal to develop a method that will simultaneously identify different substances in one sample. Such a technique allows significantly increasing the speed of one definition and reducing the cost of conducting it. Such a method has not only economic but also ecological significance, since it can be effectively used for monitoring environmental studies.The aim of the study – to development a technique for the analytical determination of cyflufenamide and difenoconazole microquantities in water simultaneously.Research Methods. Research includes extraction, concentration and chromatography of prepared water samples. The quantitative determination of cyflufenamide and difenoconazole was carried out by gas-liquid chromatography using an electron-capture detector.Results and Discussion. The best result of active substances extraction from water samples was achieved using chloroform as an extractant. Chromatography conditions were established under which the retention time is: for cyflufenamide – 3.19 minutes; difenoconazole – 12.58 minutes. Limit of the quantification of this method for cyflufenamide is 0.001 mg/dm3, difenoconazole – 0.001 mg/dm3.Conclusions. The conditions for simultaneous determination of cyflufenamide and difenoconazole by the method of gas-liquid chromatography are developed with their simultaneous presence in the water sample, which allows significantly speeding up the analysis and reducing the cost of conducting it.

scholarly journals Evaluation of Some Pesticide Residues in Fruits import by High Performance Liquid Chromatography

2017 ◽  
Vol 27 (4) ◽  
Author(s):  
Lamees Munef Abdul-Latef ◽  
Iyad Abdul-Muhsan Ahmed
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Pesticide Residues ◽  
High Performance ◽  
Fruits And Vegetables ◽  
Current Knowledge ◽  
Maximum Residue Limits ◽  
Exposure Risks ◽  
Core Mixture

Pesticide residues have been found in various fruits and vegetables.  This studycollected 24 samples and reported a method based on High Performance Liquid Chromatography (HPLC). For determination of pesticide residues used in Some fruits which were collected from different markets of Baghdad city to make) 24) samples from (peel , core, mixture) for each type of fruits markets as:  Oranges( Egypt , Africa), Pomegranate ( Egypt), Mango ( Kenya ), Pears (China),  Plum fruits ( Africa ) , Kiwi (Turkey ) .That detective of ( 5 ) different  pesticides (diazinon,  malathion, chlorpyrifos ,parathion  and cypermethrin). The results were detected of multi-residues of  pesticides on the fruit in ( peel , core , mixture ) may be in the limit of Maximum residue limits(MRL) or higher of it   . The pesticides detected that exceeding the limits are: cypermethrin  in Kiwi (peel, core and mixture)at(0.204,0.038, 0.537), in pomegranate detected in (peel and mixture) at (0.509,0.189) mg/kg , Diazinondetccted in Egyptian orange in (peel ,core and mixture) at (0.031,0.207, 0.099) mg/kg . Malathion and Parathion was not detected at any type of fruits and  that results was compared with codex of FAO/WHO(2013). That data is important to monitor residues in food and to fill gaps in current knowledge would be helpful in assessing human exposure risks from ingestion of contaminated Fruits Imported to our country .

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