Organophosphorus pesticides parathion

A.Y. Kolosova, J.H. Park, S.A. Eremin, S.J. Kang and D.H. Chung, Fluorescence polarization immunoassay based on a monoclonal antibody for the detection of the organophosphorus pesticide parathion-methyl. J. Agric. Food Chem. 51, 1107-1114 (2003). 

The few pesticides investigated so far on BDD electrodes using voltammetric methods include some carbamate pesticides (carbaryl, " carbendazim ), and organophosphorus pesticides (parathion, methyl parathion, and fenamiphos ). Determination of the latter group is based on the reduction of the nitro group and thus these pesticides are among the few examples on utilization of BDD electrodes for electroreduction. Carbamate pesticides, the N-substituted esters of carbamic... 

Among the best known organophosphorus pesticides are malathion, parathion, schradan and dimefox. 

DOT/UN/NA/IMCO shipping Methyl parathion, liquid (DOT) Methyl parathion mixture, dry (DOT) methyl parathion, solid (DOT) UN 3017 organophosphorus pesticides, liquid, toxic, flammable, not otherwise specified HSDB 1999 RTECS 1989... 

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). 

Garcia-Repetto R, Martinez D, Repetto M. 1997. Biodisposition study of the organophosphorus pesticide, methyl-parathion. Bull Environ Contam Toxicol 59 901-908. 

Lino CM, da Silveira MIN. 1992. Organophosphorus pesticide residues in cow s milk Levels of c/s -mevinfos, methyl-parathion, and paraoxon. Bull Environ Contam Toxicol 49 211-216. 

The amount of adsorbed chemical is controlled by both properties of the chemical and of the clay material. The clay saturating cation is a major factor affecting the adsorption of the organophosphorus pesticide. The adsorption isotherm of parathion from an aqueous solution onto montmorillonite saturated with various cations (Fig. 8.32), shows that the sorption sequence (Al > Na > Ca ) is not in agreement with any of the ionic series based on ionic properties. This shows that, in parathion-montmoriUonite interactions in aqueous suspension, such factors as clay dispersion, steric effects, and hydration shells are dominant in the sorption process. In general, organophosphorus adsorption on clays is described by the Freundhch equation, and the values for parathion sorption are 3 for Ca +-kaoUnite, 125 for Ca -montmorillonite, and 145 for Ca -attapulgite. 

Five organophosphorus pesticides were chosen that could be iso-thermally and simultaneously analyzed by gas chromatography using an N-P TSD detector. They are all currently commercially used and exhibit a wide range of physicochemical properties (Table I). Also influencing the choice of these pesticides was the fact that volatilization data measured from soil and water under controlled laboratory conditions are scarce for methyl parathion, parathion, and diazinon (14-17), and are not available for malathion and mevinphos. Technical mevinphos (60% E-isomer, Shell Development Co.), diazinon (87.2%, Ciba-Geigy Corp.), and malathion (93.3%, American Cyanamld), and analytical grade methyl parathion (99%, Monsanto) and parathion (98%, Stauffer Chemical Co.) were used. 

Gratzel et al. demonstrated a wide variety of organophosphorus pesticides, including paraoxon, parathion, and malathion, which possess aromatic side chains and/or sulfur atoms can be totally decomposed into carbon dioxide and the corresponding mineral acids by irradiation in a solar simulator in the presence of anatase TiO2 suspensions [41]. The balanced equation based on carbon dioxide evolution for the mineralization of parathion is represented by Eq. (6) ... 

Organophosphorus acid pesticides Parathion and methylparathion Insecticide 300-800... 

As organochlorine pesticides fell into disfavor the use of organophosphorus pesticides (OPPs) multiplied and with them a concomitant and increase in morbidity and mortality—particularly among sprayers and farm workers. The OPPs—especially Parathion and Phosdrin—account for more deaths than any other class of pesticides (Moses, ref. 164). OPPs are acetylcholinesterase inhibitors with potentially disabling neurotoxic effects. 

The technique was used to determine several organophosphorus pesticides (E)- and (Z)-Mevinphos, Dichlorvos, Azinphos-methyl, Azinphosethyl, Parathion-methyl, Parathion-ethyl, Malathion, Fenitrothion, Fenthion, Chlorfenvinphos and Diazinon, in groundwater. 

In connection with the development of an analytical method (13) for the determination of organophosphorus pesticides in human blood and urine, mass spectral confirmation of a series of methylated and ethylated derivatives of the hydrolytic and metabolic products of these insecticides was required. The urine of an individual occupationally exposed to parathion was extracted with a 1 1 (v/v) solvent mixture of acetonitrile and diethyl ether. Simultaneously, the intact organophosphorus insecticides were hydrolyzed by adding a portion of 5N hydrochloric acid to... 

Organophosphorus pesticides are another example of nonionic, moderately polar compounds (Fig. 7.13). These pesticides are commonly used today and include compounds such as methyl parathion, parathion, diazinon, and dimethoate. They are used as insecticides on crops such as cotton, as fungicides on fruits, and as nematocides on soil. They are moderately polar... 

Solutes Methyl parathion and other organophosphorus pesticides. Sorbent 360 mg of C-18, precondition with 2 mL each of methanol, ethyl... 

Organophosphorus pesticides Acephate , Azinphos-methyl , Chlorpyrifos , Chlorpyriphos-methyl , Diazinon , Dichlorvos (DDVP), Dicrotophos , Dimethoate , Disulfoton , Ethoprop , Eenamiphos , Eenitrothion , Fenthion , Fosthiazate , Malathion , Methamidophos , Methidathion , Methyl-parathion , Mevinphos , Naled , Oxydemeton-methyl , Para-thion , Phorate , Phosalone , Phosmet , Pirimiphos-methyl , Profenofos , Terbufos , Tetrachlorvinphos , Trichlorfon . 

Althongh strnctural feature in the molecule varies from most other organophosphorus pesticides, the toxic actions are similar to parathion and other phosphate esters. Extremely toxic by all routes of exposure cholinesterase inhibitor can present a serious inhalation hazard, if spilled, due to relatively high vapor pressure exhibits acute, delayed, and chronic effects symptoms of cholinergic effects similar to those of other organophosphates death can result from respiratory arrest ingestion of 0.3-2 g could be fatal to adult human. 

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