Organophosphorus pesticides humans

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). 

Nigg HN, Knaak JB. 2000. Blood cholinesterases as human biomarkers of organophosphorus pesticide exposure. Rev Environ Contam Toxicol 163 29-112. 

Shafik TM, Bradway DE, Enos HR, et al. 1973a. Human exposure to organophosphorus pesticides A modified procedure for the gas-liquid chromatographic analysis of alkylphosphate metabolites in urine. J Agr Food Chem 21 625-629. 

Maroni, M. (1986) Organophosphorus pesticides, in Biological Indicators for the Assessment of Human Exposure to Industrial Chemicals, L. Alessio, A. Berlin, M. Boni, and R. Roi (Eds.), Commission of the European Communities (EUR 10704), Brussels, Lusembourg, pp. 51-72. 

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. 

Lotti, M. and M.K. Johnson. 1978. Neurotoxicity of organophosphorus pesticides predictions can be based on in vitro studies with hen and human enzymes. Arch. Toxicol. 41 215-221. (Cited in Munro et al., 1994 )... 

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... 

Products of Organophosphorus Pesticide Chemicals in Human Blood and Urine, J. Agr. Food Chem. (1969) 17, 1186-9. 

Knaak JB, Dary CC, Power F, Thompson CB, Blancato JN. Physicochemical and biological data for the development of predictive organophosphorus pesticide QSARs and PBPK/PD models for human risk assessment. Crit Rev Toxicol 2004 34 143-207. 

Musshoff F, Junker H, Madea B. Simple determination of 22 organophosphorus pesticides in human blood using headspace solid-phase microextraction and gas chromatography with mass spectrometric detection. J Chromatogr Sci 2002 40 29-34. 

Kilgore, W. W Li., M. Y, and Mull, R. 1. (1977). Human Physiological Effects of Organophosphorus Pesticides in a Normal Agricultural field Population. Prelimimry Report U. Scientific A. pects. Food Protection and Toxicology Center, University of California, Davis, CA. 

Gls,son. A. O., Nguyen, J. V., Sadowski, M. A., and Ban, D. B. (2003). A liquid chroniatographyfclecirospray ionization-tandem mass. spectrometry method for quanlification of specific organophosphorus pesticide bioraarkcr in human urine. Anal. Bioanal. Chem. 376, 808-815. 

Mason, H. J., Waine, E., Stevenson, A., and Wilson, H. K. (1993). Aging and spontaneous reactivation of human plasma cholinesterase activity after inhibition by organophosphorus pesticides. Hum. Exp. Toxicol. 12, 497-503. 

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. 

Abate is less toxic in comparison to with most other organophosphorus pesticides. Among the test animals, rats showed almost 10 times greater resistance to this compound than did mice and rabbits. In humans, ingestion can cause nausea, vomiting, diarrhea, and convulsions. Intake of large amounts can result in respiratory failure. 

Organophosphorus pesticides have been the insecticides most commonly used by professional pest control bodies and homeowners for the past three decades (Jeannot and Dagnac 2006). Nevertheless, the decision of the US Environmental Protection Agency (EPA) to phase out certain uses of the organophosphate insecticides because of their potentially toxic effects to humans has led to their gradual replacement by other pesticides. Among them, synthetic pyrethroids have been manufactured since 1950 s based upon the structure of natural pyrethrins, which are chemicals with active insecticidal properties in the pyrethrum extract (a mixture of chemicals found in certain chrysanthemum flowers). Pyrethrins are very unstable in the environment, due to oxidation and UV-radiation. 

Early high-toxicity pesticides such as TEPP and parathion have now fallen out of use. Organophosphorus pesticides (and in some cases other phosphate esters such as tricresyl phosphate) are now believed to produce several responses in humans. Acute symptoms can appear within hours of exposure, intermediate syndromes within days, and a delayed response which may take months or even years to develop. The latter is known as OP-induced neuropathy (OPIDN) and is difficult to treat and may be irreversible. 

Human Exposure to Organophosphorus Pesticides. Modified Procedure for the Gas Chromatographic Determination of Alkyl Phosphate Metabolites in Urine... 

Retention of Organophosphorus Pesticides in Animals and Humans. Determination of Fenitrothion in Blood by Gas Chromatography Sangyo Igaku 16(6) 547-556 (1974) ... 

Foxenberg RJ, Ellison CA, Knaak JB, Ma C, Olson JR (2011) Cytochrome P450-specific human PBPK/PD models for the organophosphorus pesticides chlorpyrifos and parathion. Toxicology 285 57-66... 

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