Pesticides Diazinon

Kicuchi and Saito used carbon Empore disks in combination with SDB-XD Em-pore disks to extract polar (methamidophos, acephate and trichlorfon) and nonpolar pesticides (diazinon, chloroneb and simazine) from water. The water sample (500 mL) was passed through the disk and the disk simultaneously eluted with 30 mL of acetone-ethyl acetate (1 1). The samples were concentrated and analyzed by GLC/MS. 

Moore, A. and C.P. Waring. 1996. Sublethal effects of the pesticide diazinon on olfactory function in mature male Atlantic salmon parr. Jour. Fish Biol. 48 758-775. 

Stone, W.B. 1980. Bird deaths caused by pesticides used on turfgrass. N.Y. State Turf grass Conf. Proc. 4 58-62. Stone, W.B. and P.B. Gradoni. 1985. Wildlife mortality related to use of the pesticide diazinon. Northeast. Environ. Sci. 4 30-38. 

In many applications nowadays it is essential to link a mass spectrometer to the gas chromatography in order to achieve positive identification and sensitivity of analysis. Some 12 types of compounds are listed in Table 1.11(a) which are based on the application of this technique, viz. polyaromatic hydrocarbons, polychlorobenphenyls, dioxins, chloro, carbamate and triazine types of herbicides and pesticides, Diazinon, Dicamba, Imidazoline and Cyperquat herbicides and herbicide pesticide mixtures. 

The answer is D. Organophosphates react with the active site serine residue of hydrolases such as acetylcholinesterase and form a stable phosphoester modification of that serine that inactivates the enzyme toward substrate. Inhibition of acetylcholinesterase causes overstimulation of the end organs regulated by those nerves. The symptoms manifested by this patient reflect such neurologic effects resulting from the inhalation or skin absorption of the pesticide diazinon. 

The influence of surfactants is predominantly of importance in waste water ozonation studies where often comparatively high concentrations of such compounds occur. However, similar effects can occur in drinking or ground water ozonation applications. This was shown for the decomposition of the organic phosphate pesticide diazinon (phosphorotoic acid <5,<5-diethyl-o[6-methylethyl)-4-pyrimidinylJether) in aqueous solution by ozonation. This compound was found to considerably affect the surface tension of the aqueous solution, even at low concentrations (c(M) < 10 mg L l) and, thus, also influenced the oxidation mechanism (Ku et al., 1998). 

Extraction of pesticides from wool Raw sheep wool both exposed and not exposed to pesticide diazinon (Dr Ehrenstorfer, Germany) methanol (BDH, NZ) 15ml glass tubes (Kimax, USA) acetonitrile... 

PoetTS, KousbaAA, Dennison SL, TimchalkC. 2004. Physiologically based pharmacokinetic/ pharmacodynamic model for the organophosphorus pesticide diazinon. Neurotoxicology 25 1013-1030. 

A recent review has highlighted the stability of chemical species (in speciation studies) with respect to environmental matrices [1], These results are summarized in Table 4.2. It should be noted that samples must be analysed as quickly as possible after collection. The times given in this table are the maximum times that samples should be stored before analysis. It should also be noted that the guidelines given are general in nature. For example, many organophosphorus pesticides (not shown in Table 4.2) can be preserved by the addition of hydrochloric acid. However, as an exception to this, the (organophosphorus) pesticide diazinon breaks down when acidified. 

In the same manner in which we discussed solubility let us examine extractability. Quite frequently a compound s extractability by a supercritical fluid has no relation to its solubility in that supercritical fluid. Chapter 8 showed that the pesticide diazinon dissolves to a high level in CO2, but it is not extractable from activated carbon. Chapter 8 also discusses separation of acetic acid from water. Acetic acid is infinitely miscible with CO2 but it exhibits a distribution coefficient of only 0.03. Again, strictly speaking, acetic acid is extractable but we feel that extractability should be evaluated in terms of a potential practical process. Supercritical extraction of acetic acid would probably not be an attractive alternative relative to traditional distillation. On the other hand, a distribution coefficient of 0.03 might be satisfactory for the extraction of a heat-labile compound from dilute solution. Therefore, even though we have developed certain useful generalities, it is still important to evaluate each case separately. 

Ghassempour, A., Mohammadkhah, A., Najafi, F., and Rajabzadeh, M., Monitoring of the pesticide diazinon in soil, stem and surface water of rice fields. Anal. Set, 18, 779-783, 2002. 

Poet, T, S, Kousba, A. A., Denni.son, S, and Timchalk, C, (2004), Physiologically based pharmiicokineiic/pharmacodynamic model (or (he organophosphate pesticide diazinon, Neumtoxi-cology 25(6), 1013-1030. 

The feasibility of employing fluorescent tracers and video imaging analysis to quantify dermal exposure to pesticide applicators has been demonstrated under realistic field conditions. Six workers loaded a tracer with the organophosphate pesticide, diazinon, into air blast sprayers, and conducted normal dormant spraying in pear orchards. They were examined prior to and immediately after the application. UV-A illumination produced fluorescence on the skin surface, and the pattern of exposure was digitized with a video imaging system. Quantifiable levels of tracer were detected beneath cotton coveralls on five workers. The distribution of exposure over the body surface varied widely due to differences in protective clothing use, work practices and environmental conditions. This assessment method produced exposure values at variance with those calculated by the traditional patch technique. 

The residues of four pesticides (diazinon, caibaryl, malathion, fenitrothion) were recovered from sesame seeds and baseline resolved on a Cjg column (2 = 225 nm) using a 50/50 acetonitrile/water (0.1% acetic acid) mobile phase [969]. Excellent separation and elution were achieved in 21 min. Linearity was obtained over the range 2-4500 ng/mL with detection limits of 5-50 ng/mL (analyte dependent). 

Rapid Determination of the Organo-phosphorus Pesticides Diazinon and Dichlorovos in Blood by Gas Chromatography... 

Ibanez M, Sancho JV, Pozo OJ, Hernandez F, Niessen WMA (2005) Use of quadrupole time-of-flight mass spectrometry in the elucidation of unknown compounds present in environmentd water. Rapid Commun Mass Spectrom 19(2) 169-178. doi 10.1002/rcm. 1764 Ibanez M, Sancho JV, Pozo OJ, Hernandez F (2006) Use of liquid chromatography quadrupole time-of-flight mass spectrometry in the elucidation of transformation products and metabolites of pesticides. Diazinon as a case study. And Bioand Chem 384(2) 448- 57. doi 10.1007/ S00216-005-0167-6... 

T. S. Poet, A. A. Kousba, S. L. Dennison and C. Timchalk, Physiologically based pharmacokinetic/pharmacodynamic model for the organophos-phorus pesticide diazinon. Neurotoxicology, 2004,25,1013-1030. 

O. A. Timofeeva, C. S. Roegge, F. J. Seidler, T. A. Slotkin and E. D. Levin, Persistent cognitive alterations in rats after early postnatal exposure to low doses of the organophosphate pesticide, diazinon, Neurotox-icol. TeratoL, 2008, 30, 38-45. 

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