Organophosphorus pesticides, determining

Specification of the GC Detectors Used for Organophosphorus Pesticides Determination ... 

LC-MS Conditions for Organophosphorus Pesticides Determination Ionization Modes, m/z Used for Quantification and Detection Limits ... 

Precursor Ion m/z and Product Ion m/z Monitored in MRM Mode for Some Organophosphorus Pesticides Determined by LC-MS/MS ... 

Methyl parathion was determined in dog and human serum using a benzene extraction procedure followed by GC/FID detection (Braeckman et al. 1980, 1983 DePotter et al. 1978). An alkali flame FID (nitrogen-phosphorus) detector increased the specificity of FID for the organophosphorus pesticides. The detection limit was in the low ppb (pg/L). In a comparison of rat blood and brain tissue samples analyzed by both GC/FPD and GC/FID, Gabica et al. (1971) found that GC/FPD provided better specificity. The minimum detectable level for both techniques was 3.0 ppb, but GC/FPD was more selective. The EPA-recommended method for analysis of low levels (<0.1 ppm) of methyl parathion in tissue, blood, and urine is GC/FPD for phosphorus (EPA 1980d). Methyl parathion is not thermally stable above 120 °C (Keith and Walters 1985). 

Izmirova H. 1980. Methods for determination of exposure of agricultural workers to organophosphorus pesticides. In Tordoir WF, Van Heemstra EA, eds. Field worker exposure during pesticide application. New York, NY Elsevier Sci. Publ. Co., 169-172. 

Garcia-Valcarcel AI, Tadeo JL (2009) A combination of ultrasonic assisted extraction with LC-MS/MS for the determination of organophosphorus pesticides in sludge. Anal Chim Acta 641 (1—2) 117—123... 

W.R. Everett and G.A. Rechnitz, Mediated bioelectrocatalytic determination of organophosphorus pesticides with a tyrosinase-based oxygen biosensor. Anal. Chem. 70, 807-810 (1998). 

Lacorte S. and Barceld D., 1995. Determination of organophosphorus pesticides and their transformation products in river waters by automated online solid-phase extraction followed by thermospray liquid chromatography. J Chromatogr A 712 103. 

Chau and Terry [146] reported the formation of penta-fluorobenzyl derivatives of ten herbicidal acids including 4-chloro-2-methyl-phenoxy acetic acid [145]. They found that 5h was an optimum reaction time at room temperature with pentafluorobenzyl bromide in the presence of potassium carbonate solution. Agemian and Chau [147] studied the residue analysis of 4-chloro-2-methyl phenoxy acetic acid and 4-chloro-2-methyl phenoxy butyric acid from water samples by making the pentafluorobenzyl derivatives. Bromination [148], nitrification [149] and esterification with halogenated alcohol [145] have also been used to study the residue analysis of 4-chloro-2-methyl phenoxy acetic acid and 4-chloro-2-methyl phenoxybutyric acid. Recently pentafluorobenzyl derivatives of phenols and carboxylic acids were prepared for detection by electron capture at very low levels [150, 151]. Pentafluorobenzyl bromide has also been used for the analytical determination of organophosphorus pesticides [152],... 

Mitchell TH, Ruzicka JH, Thomson J, et al. 1968. The chromatographic determination of organophosphorus pesticides. Part III. The effect of irradiation on the parent compounds. J Chromatogr 32 17-23. 

Ruzicka JH, Thompson J, Wheals DD. 1967. The gas chromatographic determination of organophosphorus pesticides. Part II. A comparative study of hydrolysis rates. J Chromatogr 31 37. 

Figure 2. Experimentally determined and EXAMS predicted percents volatilized (in one day) for five organophosphorus pesticides incorporated into water, water-soil, and soil systems. Computer predictions are not shown for mevinphos or for dry soil.

A snpercritical flnid extraction (SEE) method for the determination in strawberries of a number of commonly used organochlorine insecticides, organophosphorus pesticides, and dichloroaniUde fungicides (Pearce et al., 1997). 

The mode of injection in GC-based methods can affect the recoveries of diazinon. In a study of the determination of organophosphorus pesticides in milk and butterfat, it was found that the recoveries of diazinon from butterfat, calculated relative to organic solutions of standard compounds, were 125% and 84% for splitless and hot on-column injections, respectively (Emey et al. 1993). Recoveries from milk were not dependent on the mode of injection. It was concluded that the sample matrix served to increase diazinon transfer to the GC column by reducing thermal stress imposed on the analytes and by blocking active sites within the injector. Therefore, on-column injection should be used in order to prevent bias when organic solutions of standard compounds are used for quantitation if this is not possible, the matrix must be present at low concentrations or the calibration standards must be prepared in residue-free samples to avoid unknown bias. 

Brown RL, Farmer CN, Millar RG. 1987. Optimization of sweep codistillation apparatus for determination of coumaphos and other organophosphorus pesticide residues in animal fat. J Assoc Off Anal Chem 70(3) 442-445. 

Drevenkar V, Stengl B, Tkalcevic B, et al. 1983. Occupational exposure control by simultaneous determination of N-methylcarbamates and organophosphorus pesticide residues in human urine. Int J Environ Anal Chem 14 215-230. 

Driss MR, Hennion M-C, Bouguerra ML. 1993. Determination of carbaryl and some organophosphorus pesticides in drinking water using on-line liquid chromatographic preconcentration techniques. J Chromatogr 639 352-358. 

EPA. 1992a. Method 1657. The determination of organophosphorus pesticides in municipal and industrial wastewater. In Methods for the determination of nonconventional pesticides in municipal and industrial wastewater. U.S. Environmental Protection Agency, Office of Water, Washington, DC. 

Kwakman PJM, Vreuls JJ, Brinkman UAT, et al. 1992. Determination of organophosphorus pesticides in aqueous samples by on-line membrane disk extraction and capillary gas chromatography. Chromatographia 34 41-47. 

S Lacorte, D Barcelo. Improvements in the determination of organophosphorus pesticides in ground and wastewater samples from interlaboratory studies by automated on-line liquid-solid extraction followed by liquid chromatography diode array detection. J Chromatogr A 725 85-92, 1996. 

S Lacorte, D Barcelo. Determination of part per trillion levels of organophosphorus pesticides in groundwater by automated on-line solid-phase extraction followed by thermospray liquid chromatography mass spectrometry. Anal Chem 68 2464 -2478, 1998. 

A Lagana, G D Ascenzo, G Fago, A Marino. Determination of organophosphorus pesticides and metabolites in crops by solid phase extraction followed by liquid chromatography/diode array detection. Chromatographia 46 256-264, 1997. 

JJ Blaha, PJ Jackson. Multiresidue method for quantitative determination of organophosphorus pesticides in food. J Assoc Off Anal Chem 68 1095-1099, 1985. 

M De Paoli, TM Barbina, R Mondini, A Pezzoni, A Valentino. Determination of organophosphorus pesticides in fruits by on-line size-exclusion chromatography-liquid chromatography-gas chromatography-flame photometric detection. J Chromatogr 626 145-150, 1992. 

CG Pinto, JL Pavon, BM Cordero. Cloud point preconcentration and high performance liquid chromatographic determination of organophosphorus pesticides with dual electrochemical detection. Anal Chem 67 2606-2612, 1995. 

C Molina, P Grasso, E Benfenati, D Barcelo. Automated sample preparation with extraction columns followed by liquid chromatography-ionspray mass spectrometry. Interferences, determination and degradation of polar organophosphorus pesticides in water samples. J Chromatogr A 737 47-58, 1996. 

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