Search results for "PEST"
showing 10 items of 1124 documents
Retrospective screening of pesticide metabolites in ambient air using liquid chromatography coupled to high-resolution mass spectrometry
2015
A new methodology for the retrospective screening of pesticide metabolites in ambient air was developed, using liquid chromatography coupled to Orbitrap high-resolution mass spectrometry (UHPLC-HRMS), including two systematic workflows (i) post-run target screening (suspect screening) and (ii) non-target screening. An accurate-mass database was built and used for the post-run screening analysis. The database contained 240 pesticide metabolites found in different matrixes such as air, soil, water, plants, animals and humans. For non-target analysis, a "fragmentation-degradation" relationship strategy was selected. The proposed methodology was applied to 31 air samples (PM10) collected in the…
Sample preparation methods for the determination of pesticides in foods using CE-UV/MS.
2010
Much progress has been made in pesticide analysis over the past decade, during this time hyphenated techniques involving highly efficient separation with sensitive detection have become the techniques of choice. Among these, methods based on separation with mass spectrometric detection have resulted in greater likelihood of identification and are acknowledged to be extremely useful and authoritative methods for the determination of pesticide residues but the inherent advantages of the use of CE as a separation technique are well-known and can be summarized as high separation efficiency, low analysis time, high resolution power, and low consumption of samples and reagents. Although UV is the…
Solid-Phase Extraction of Organochlorine Pesticides from Water Samples
1990
Abstract A procedure for the accumulation of organochiorine pesticides by reversed-phase adsorption on octadecylsilica glass microcolumns was used for the isolation and concentration from spiked distilled and natural waters. The pesticides were eluted from the octadecylsilica with light petroleum, and analyzed by gas chromatography using an electron capture detector. The average recovery was over 90% in spiked water samples at 0.1 ng/ml. The performance of the octadecylsilica when applied to the analysis of water samples were compared with the Rodier and the APHA solvent extraction methods.
Recent trends in liquid chromatography-tandem mass spectrometry to determine pesticides and their metabolites in food
2007
Abstract The applications of liquid chromatography-mass spectrometry (LC-MS) have exploded in innumerable analytical fields, including pesticide-residue determination. There is no doubt that LC-MS is currently competing with gas chromatography (GC)-MS for the status of ‘reference’ analytical technique to determine pesticide residues and that its ever-increasing application is bound to the evolution of modern instruments and their growing performance qualities. We highlight the large number and variety of pesticides that can be readily determined using such instruments, the respective merits of the different mass analyzers, and the improvements brought about by tandem MS (MS 2 ). We also dis…
Capabilities of different liquid chromatography tandem mass spectrometry systems in determining pesticide residues in food
2007
Abstract Three different liquid chromatography–mass spectrometry (LC–MS) instruments equipped with triple quadrupole (QqQ), quadrupole ion trap (QIT) and quadrupole-time-of-flight (QqTOF), suitable to carry out tandem mass spectrometry, were examined to determine pesticide residues in food. Twelve pesticides (acrinathrin, bupirimate, buprofezin, cyproconazole, λ-cyhalothrin, fluvalinate, hexaflumuron, kresoxim-methyl, propanil, pyrifenox, pyriproxyfen and tebufenpyrad) and six matrices (oranges, strawberries, cherries, peaches, apricots and pears) were taken as model. The comparison was focused on two aspects: the quantitative, covering sensitivity, precision and accuracy as well as the qua…
The Role of the Liquid Chromatography-Mass Spectrometry in Pesticide Residue Determination in Food
2008
The use of liquid chromatography (LC) in pesticide residue determination was usually limited to groups of compounds or single compounds for which no suitable gas chromatographic (GC) conditions were available. However, recent developments have significantly enlarged the LC scope in this field of analysis. One of the most important advances was the on-line coupling of efficient LC separation with mass spectrometry detectors (LC-MS and LC-MS/MS) that makes this technique an excellent method for the determination of pesticides and their transformation products in complex matrices such as food. This review considers the application of LC-MS/MS in this field. Emphasis is placed on the tandem MS …
Last trends in pesticide residue determination by liquid chromatography–mass spectrometry
2014
Liquid chromatography–mass spectrometry (LC–MS) is as an excellent analytical tool in the determination of pesticides. Multiresidue analysis of these compounds at trace levels is one of the oldest analytical schemes within environmental and food safety. However, the issue of “pesticide residue determination” is still a hot topic for the analytical community. This review discusses current approaches and recent advances in using LC–MS for pesticide identification and quantification. We outline how MS has influenced the sample preparation process. We critically assess and compare various mass spectrometers, highlighting their strengths and limitations. We, then, review the main applications of…
Evaluation of 10 pesticide residues in oranges and tangerines from Valencia (Spain)
2006
Abstract One hundred and sixteen orange and tangerine samples from an agricultural cooperative of the Valencian Community (Spain) were analyzed for bitertanol, carbendazim, hexythiazox, imazalil, imidacloprid, methidathion, methiocarb, pyriproxyfen, thiabendazole, and trichlorfon by liquid chromatography–mass spectrometry (LC–MS) after a conventional multiresidue extraction procedure. Of 52 samples that contained pesticide residues, carbendazim was detected in 27 (51.9%) in the concentration range of 0.02–0.04 mg kg−1, hexythiazox in 22 (42.3%) in the concentration range of 0.02–0.05 mg kg−1, imazalil in 8 (15.0%) in the concentration range of 0.02–1.2 mg kg−1, imidacloprid in 5 (9.6%) in a…
Analytical Methods for Pesticide Residue Determination in Bee Products
2002
Monitoring pesticide residues in honey, wax, and bees helps to assess the potential risk of these products to consumer health and gives information on the pesticide treatments that have been used on the field crops surrounding the hives. The present review seeks to discuss the basic principles and recent developments in pesticide analysis in bee products and their application in monitoring programs. Consideration is given to extraction, cleanup, chromatographic separation, and detection techniques.
Determination of Urea Pesticide Residues in Vegetable, Soil, and Water Samples
2003
The main physico-chemical, toxicological, and environmental properties of urea pesticides are summarized. General characteristics of analytical methods for residues of phenylurea herbicides (PUHs), sulfonylurea herbicides (SUHs), and Benzoylurea insecticides (BUIs) in crops, soil, and water samples, employed in the last 5 years are reviewed. Provided it is information about liquid-liquid and solid-phase extraction of the samples and clean-up steps. The applications of gas chromatography (GC), liquid chromatography (LC), and capillary electrophoresis (CE) techniques in the analysis of these compounds are exposed in tabular form and commented on. Sensitivity and instrument conditions of liqui…