Pesticides environmental application

At the fundamental level of equilibrium modeling the advantages are many. The model can combine a number of compartments through simple relationship to describe a realistic environment within which chemicals can be ranked and compared. Primary compartments that chemicals will tend to migrate toward or accumulate in can be identified. The arrangement of compartments and their volumes can be selected to address specific environmental scenarios. Data requirements are minimal, if the water solubility and vapor pressure of a chemical are known, other properties can be estimated, and a reasonable estimate of partitioning characteristics can be made. This is an invaluable tool in the early evaluation of chemical, whether the model be applied to projected environmental hazard or evaluation of the behavior of a chemical in an environmental application, as with pesticides. Finally, the approach is mathematically very simple and can be handled on simple computing devices. 

Environmental applications of HRP include immunoassays for pesticide detection and the development of methods for waste water treatment and detoxification. Examples of the latter include removal of aromatic amines and phenols from waste water (280-282), and phenols from coal-conversion waters (283). A method for the removal of chlorinated phenols from waste water using immobilised HRP has been reported (284). Additives such as polyethylene glycol can increase the efficiency of peroxidase-catalyzed polymerization and precipitation of substituted phenols and amines in waste or drinking water (285). The enzyme can also be used in biobleaching reactions, for example, in the decolorization of bleach plant effluent (286). 

Many enzymes have been entrapped successfully in sol-gel matrices44,45d h. The entrapment of parathion hydrolase44,51, which is capable of detoxifying and detecting the pesticide Parathion, demonstrates the potential of the sol-gel methodology in environmental applications. 

Dombrowski, T.R., E.M. Thurman, and G.B. Mohrman (1997). Evaluation of immunoassay for the determination of pesticides at a large-scale groundwater contamination site. In D.S. Aga and E.M. Thurman, eds., Immunochemical Technology for Environmental Applications. ACS Symposium Series 657. Washington, DC American Chemical Society, pp. 221-233. 

The HPLC/MS technique has been only recently initiated into environmental applications. It is considered a non-routine application, and is conducted mostly by the laboratories specializing in pesticide analysis. 

Polyhaloacetic acids and their partially hydrodehalogenated products represent a second important family of herbicide-/pesticide-derived substrates. In their review on the environmental applications of industrial electrochemistry, Juttner and co-authors (Juttner et al. 2000) documented the electroreductive dechlorination of dichloroacetic acid (a by-product of monochloroacetic acid), a way to recover the valuable compound and avoid wastes. The electrochemical reduction of polychloro- and polybromo-derivatives was performed by Korshin and Jensen (2001) on Cu and Au cathodes. Complete dehalogenation was obtained for all substrates, but for monochloroacetic acid. To overcome the intrinsic poor reactivity of the monochloro-derivative the photoelectrochemical properties of a p-doped SiC electrode were investigated (Schnabel et al. 2001) however, the dehalogenation stopped at monochloroacetic acid. 

Aaron, J. -J. and Oturan, M. A. (2001) New photochemical and electrochemical methods for the degradation of pesticides in aqueous media. Environmental applications. Turk. J. Chem. 25, 509-520. 

Spencer, W.R (1976) Vapor pressure and vapor loss. In A Literature Survey of Benchmark Pesticides. The George Washington University Medical Center, Department of Medical and Public Affairs, Science Communication Division, Washington DC. pp. 72-165. Staudinger, J., Roberts, P.V. (1996) A critical review of Henry s law constants for environmental applications. Crit. Rev. Environ. 

Highly hydrophobic sorbents including porous carbon and copolymers of styrene and divinylbenzene (SDB) were widely investigated for environmental applications. The particle-loaded membranes containing modified SDB particles with surface sulfonic acid groups were successfully used for recovering different alcohols, phenols, aldehydes, ketones, or esters from aqueous samples [221]. Carbon-based PLM were also used for isolation of highly polar pesticides from water [222]. 

The tremendous achievements which have been accomplished by the judicious use of pesticides in increased world-wide food production and the control of vector-bome diseases are very evident. In addition, pesticidal materials contribute to the effective control of undesirable species of pests including insects, plants, bacteria, fungi, etc., and assist in the nutrition, growth, and reproduction of certain desirable species. However, because of widespread use in these applications, pesticides have proliferated intensely in the biosphere and thus have significantly contributed to problems of environmental pollution. For example, the effects of these chemicals on public health and the survival of species of fish and wildlife are two specific areas of critical concern. The attention which has been focused in recent years on the occiurence of residues of pesticides and their metabohtes, as well as other industrially significant chemicals in the environment, is demonstrated by the numerous reports of various official and unofficial committees of inquiry which have considered this problem and have reported the results of large numbers of assays of pesticide residues in such diverse substrates as human and animal tissues, food, plants, water, soil, and air. 

The effect of irreversible inhibition of acetylcholinesterase has been used in dendrimer-based electrochemical biosensors for environmental applications. Acetylcholinesterase is a very efficient protein catalyst for the hydrolysis of its physiological substrate acetylcholine. Organophosphorus and carbamic pesticides, heavy metals and detergents exert strong specific... 

The main practical environmental application of SPR has been as an immunosensor for the detection of phytosanitary products (Mullet, 2000). Recently, SPR immunodetection of 2,4D (Kim et al., 2007), DDT (Mauriz et al., 2006a, 2007), chlorpyrifos and carbaryl pesticides (Mauriz et al., 2006b) was found ten times more sensitive than ELISA methods, with detection limits in the ppt range, and an analysis time of less than 20 min. 

MAJOR PRODUCT APPLICATIONS pesticides, herbicides, fertilizers, absorbents, drilling mud, joint compounds, neutralizers, asphalt thickeners, adhesives, paints, coatings, sealants, environmental remediation materials, antidiarrheal medication, gels... 

Abstract Indoor contamination is one source of exposure to toxic pollutants and has been classified as a high environmental risk. Epidemiological research linked health effects including childhood leukemia and neuroblastoma to the indoor occurrence of pesticides. Pesticides in indoor environments contribute to human exposure via inhalation, non dietary ingestion and dermal contact. Sources for pesticides indoors are direct applications, pesticides used in varnishes, colors, adhesives, etc., or in finishing textiles, leather, carpets, etc., and pesticides brought in from outdoors. Results for pesticides in indoor environments from different countries and obtained under different conditions are compiled in this chapter. They are discussed by applying two approaches (1) the comparison with reference values... 

For a good discussion of on-line SPE coupled to HPLC, the work of Hennion and Pichon (1994) and Hennion and co-workers (1990) discuss environmental applications. In their work, the styrene-divinylbenzene copolymers are used as SPE columns with good capacity for many of the environmentally relevant contaminants and allow for direct analysis by HPLC. Hennion and Pichon (1994) discuss and review a number of studies on pesticides and related compounds by on-line SPE. There is also more discussion of on-line SPE methods coupled to GC/MS in Chapter 10. 

An environmental application of liquid extraction is the removal of trace organics from water. Examples are the separation of acetic acid-water mixtures and removal of solvents, insecticides, pesticides, etc., from water. It can also be applied to the separation of liquids with close boiling points or those that form azeotropes, such that distillation is not useful. In addition, zero- or low-volatility compounds, such as metals and organometallic derivatives, can be separated by liquid extraction as can mixtures of water-hydrogen bonded compounds, such as formaldehyde. Solid extraction (leaching) can be used to remove organics or heavy metals from contaminated soils, sludges or contaminated equipment. 

Pesticide Residues Pesticide residue analysis often requires elaborate sample preparation procedures and analyte enrichment, which might involve extraction (homogenization, solvent extraction), clean-up (solvent partitioning, GPC, SPE), and analyte derivatization.21 Examples are shown in the environmental applications section. Common pesticide residues found in food crops, vegetables, or fruit are ... 

Assay application. At this point major differences appear between the historical use of clinical immunoassays and the potential applications of environmental and pesticide immunoassays. Most clinical assays have been applied to simple or well defined and consistent matrices such as urine or serum. In contrast, most matrices likely to be analyzed for pesticides are more complex, less well defined, and more variable. The potential for serious problems with matrix effects in the environmental field is far greater than most clinical immunoassays have encountered. The application of immunoassays to environmental analysis requires sampling strategies, cleanup procedures, and data handling fundamentally similar to those presently in use in any good analytical lab. The critical factor in the success of immunochemical technology will likely be competence... 

Slobodnik, J., B.L.M. van Baar, and U.A.Th. Brinkman. 1995. Column liquid chromatography-mass spectrometry seleded techniques in environmental applications for polar pesticides and related compounds. J. Chromatogr. A 703 81-121. 

It is used in the mining industry to recover metals such as copper and nickel. Parasite plants, based on solvent extraction, are used in the phosphate industry to recover by-product uranium from crude phosphoric acid. The uranium concentration in phosphoric acid is very low but, because of the high volume of phosphoric acid that is produced to meet agricultural needs, considerable uranium can be recovered using solvent extraction. In the nuclear industry [5], solvent extraction is used to purify uranium and plutonium [using the plutonium and uranium recovery by extraction (PUREX) process], zirconium from hafnium, and for many other applications. It is also used in environmental applications to clean soil, say, to remove polychlorinated biphenyls (PCBs), dioxins, pesticides, and other hazardous pollutants. 

C. Wittmann, R.D. Schmid, S. Loffler, A. Zell, Application of a Neural Network for Pattern Recognition of Pesticides in Water Samples by Different Immunochemical Techniques , in Immunochemical Technology for Environmental Applications, eds. D.S. Aga, E.M. Thurman, ACS Symposium Series 657, American Chemical Society, Washington, DC, 343-360,1997. 

EPA has identified several factors that may contribute to risks from the environmental application of genetically altered microbial pesticides. EPA has considered these factors in developing its... 

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