Water pesticide control

Agricultural mnoff is a large contributor to etrophication in lakes and other natural bodies of water. Effective control measures have yet to be developed for this problem. Runoff of pesticides is also receiving increasing attention. 

JoshiHC. 1987. Pesticide residues in some fish ponds in West Bengal (India). Technical Annual-Indian Association for Water Pollution Control 14 35-38. 

Mossman DJ, Schnoor JL, Stumm W. 1988. Predicting the effects of a pesticide release of the Rhine River. J Water Pollut Control Fed 6() 1806-1812. 

Hill, D.W. and McCarty, P.L. Anaerobic degradation of selected chlorinated hydrocarbon pesticides, J. Water PoIIut. Control Fed, 39 1259-1277, 1967. 

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. 

The U.S. Congress enacted the Federal Water Pollution Control Act (FWPCA) in 1972. The act was significantly amended in 1977 and has since become known as the CWA. It was again amended by the Water Quality Act of 1987. The CWA applies to aU industries that generate wastewater discharges. Some of its provisions are particularly applicable to the pesticide industry. 

Oberacker, D.A. Incineration options for disposal of waste pesticides. In Pesticide Waste Disposal Technology Bridges, J.S., Dempsey, C.R., Eds. Noyes Data Corporation Park Ridge, NJ, 1988. Eckenfelder, W.W., Jr. Industrial Water Pollution Control, 2nd ed. McGraw-Hill New York, 1989. McNally, R. Tougher rules challenge future for injection wells. Petrol. Eng. Int. 1987, July, 28-30. Zimpro, Inc. Report on Wet Air Oxidation for Pesticide Chemical Manufacturing Wastes, prepared for G. M. Jett, USEPA Rothchild Wisconsin, 1980. 

The adsorption of ions on iron oxides regulates the mobility of species in various parts of the ecosystem (biota, soils, rivers, lakes, oceans) and thereby their transport betv een these parts. Examples are the uptake of plant nutrients from soil and the movement of pesticides and other pollutants from soils into aquatic systems. In such environments various ions often compete with each other for adsorption sites. Adsorption is the essential precursor of metal substitution (see Chap. 3), dissolution reactions (see Chap. 12) and many interconversions (see Chap. 14). It also has a role in the synthesis of iron oxides and in crystal growth. In industry, adsorption on iron oxides is of relevance to flotation processes, water pollution control and waste and anticorrosion treatments. 

Supplement to the 15 th edn. of Standard Methods for the Examination of Water and Waste Water. Selected Analytical Methods Approved and Cited by the US Environmental Protection agency. American Public Health Association, American Waterworks Association, Water Pollution Control Federation, Sept. (1978). Methods S60 and S63. Methods for benzidine, chlorinated organic compounds, pentachlorophenol and pesticides in water and waste water (Interim, Pending issuance of methods for organic analysis of water and wastes, Sept. 1978), Environmental Protection Agency, Environmental Monitoring and Support Laboratory (EMSL). 

US Federal Water Pollution Control Administration. FWPCA Method for Chlorinated Hydrocarbon Pesticides in Water and Wastewater, Cincinnati, Federal Water Pollution Control Administration, 29 pp. (1969). 

Schwartz, H.J. (1967) Microbial degradation of pesticides in aqueous solutions. J. Water Pollut. Control Fed. 39, 1701. 

At present, there are generally two basic situations involving water supply contamination by pesticides chronic contamination, which is usually at levels of less than 1 p.p.b., and short term and higher level contamination. The chronic contamination results from the more or less continuous bleed-off of pesticide residues from land and continuous or periodic discharges from industrial wastes. The second or high level contamination may involve accidents, massive runoff from land following heavy rains, or direct pesticide applications to water to control unwanted fish, insects, or aquatic plants. 

Okey, R.W., Bogan, R.H. (1965) Apparent involvement of electronic mechanisms in limiting microbial metabolism of pesticides. J. Water Pollut. Control Eed. 37, 692-712. 

IN WATER pollution control as well as with mine safety and pesticides, the onset of the New Deal brought a return of government activism. But progress came only slowly and haltingly. 

In retrospect, the 1948 act is often described as a forerunner of today s complex regulatory system, the first federal law to address water pollution comprehensively. But it was, at best, an opportunity missed. The severe verdict pronounced by Kenneth Reid— 5 years hence we will be forced to admit that the present bill was a failure 25—turned out wrong only in the timing. Like the pesticide act enacted the previous year, the Water Pollution Control Act manifested the federal government s refusal to invoke its powers against the growing problem of chemical pollution. ... 

The analytical solution to Equation 2 for a range of boundary conditions is a model of pesticide fate that has been used under a variety of laboratory situations to study the basic principles of soil-water-pesticide interaction. It is in fact limited to such laboratory cases, as steady state water flow is an assumption used in deriving the equation. As a modeling approach it is useful in those research studies in which careful control of water and solute fluxes can be used to study degradation and adsorption. For example, Zhong et al. (11) present a study of aldicarb in which the adsorption and degradation of aldicarb, aldicarb sulfone and aldicarb-sulfoxide were simultaneously determined from laboratory soil column effluent data. The solution to a set of equations of the form of Equation 2 was used. A number of similar studies for other chemicals could be cited that have provided useful basic information on pesticide behavior in soil (4,12,13). Yet, these equations are not useful in the field unless re-formulated to describe transient water and solute fluxes rather than steady ones. Early models of pesticide fate based upon Equation 2 (14) were constrained by such assumptions, but were... 

In 1984 the California State Water Resources Control Board (SWRCB) reported that during the past 12 years pesticide contaminants have been found In 2,893 wells (1, 2). Although 54 different pesticides have been detected In these weTls about 85% of the contamination has been caused by l,2-d1bromo-3-chloropropane (DBCP), a soil fumigant that was banned seven years ago but that Is still being detected In Increasing amounts 1n wells. 

Groundwater Contamination by Pesticides. California State Water Resources Control Board, Publication No. 83-45 sp, 1983. 

Cohen, D.B., and Bowers, G.W. Water Quality and Pesticides A California Risk Assessment Program (Yol. 1), State Water Resources Control Board, Toxic Substances Control Program, Sacramento, CA, November, 1984. 

While both industrial and agricultural chemicals have been found in California ground waters, pesticides injected beneath the soil surface to control nematodes are a particular concern. The nematicide 1,2-dibromo-3-chloropropane (DBCP), which was banned in California in 1977, is the most serious example of this problem in California (1-2). Figure 1 shows the increase between 1979 and 1984 in the number of wells found to contain measurable quantities of DBCP. As of April 1984, 2522 wells contained DBCP, with over half these wells (1455) having concentrations in excess of 1.0 part per billion, the current California "action level". 

The chemical is being considered for inclusion or is included in the WHO Pesticide Evaluation Scheme (WHOPES) programme (approval programme for direct appHcation of pesticides to drinking water for control of insect vectors of disease). 

Among the main sources of the pollution of ecological systems, conventional use of pesticides in agriculture, forestry and water systems, and public health care and hygiene, should be considered. This concerns particularly aerial large-scale spraying of fields and forests, and the frequent application of pesticides to waters to control the carriers of diseases or aquatic plants in irrigation systems. 

Compared to research and development for biosensors for clinical applications [39, 40], not much research has been carried out in the field of environmental control. Biosensors for pesticide control in water are still in a developmental stag and no biosensors are commercially available to date for this field of application. Field tests are presently carried out with the mediated amperometric biosensor developed by Rawson et al. [31], but the sensitivity and specificy of this biosensor is not sufflcient for the high demands of drinking water quality control. 

In recent years, the determination of trace amounts of organic compovmds in environmental samples for routine water quality control has been performed using flow systems as an economical and straightforward alternative to chromatographic and electrophoretic methods. Great attention is specially paid to the development of FIA/SIA methods for the determination of anthropogenic pollutants such as polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and different families of pesticides... 

While the pesticides control pest infestation and disease, they can adversely affect the plants and the environment via ground water contamination, besides causing adverse side effects in humans. This has led to regulations by the EPA in the United States to curtail the use of pesticides that leach into the ground water. Triazines, a group commonly present in pesticides, have antibacterial and anti-protozoan activity, and are used in the production of atrazine, which is a controversial weed-control chemical. 

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