Contamination of surface

A comprehensive search (295) of the STORET water quaUty database, maintained by the U.S. EPA Office of Water, is used to evaluate the potential water quaUty implications of various herbicides. This database contains information on contamination of surface water (SW) and groundwater (GW) suppUes. The data are provided to give a general impression of the occurrence of a given herbicide in SW and GW (269). The U.S. EPA scheme for categorizing a chemical s carcinogenic potential is used for herbicides for which healthy advisory information (HA) is available. The U.S. EPA is continually issuing HAs for various environmental contaminants HAs available in Reference 269 were used in preparation of this article. 

Kinetics of Pesticide Biodegradation. Rates of pesticide biodegradation are important because they dictate the potential for carryover between growing seasons, contamination of surface and groundwaters, bio accumulation in macrobiota, and losses of efficacy. Pesticides are typically considered to be biodegraded via first-order kinetics, where the rate is proportional to the concentration. Figure 2 shows a typical first-order dissipation curve. 

The documented occurrence of pesticides in surface water is indicative that mnoff is an important pathway for transport of pesticide away from the site of appHcation. An estimated 160 t of atra2ine, 71 t of sima2ine, 56 t of metolachlor, and 18 t of alachlor enter the Gulf of Mexico from the Mississippi River annually as the result of mnoff (47). Field appHcation of pesticides inevitably leads to pesticide contamination of surface mnoff water unless mnoff does not occur while pesticide residues remain on the surface of the soil. The amount of pesticides transported in a field in mnoff varies from site to site. It is controUed by the timing of mnoff events, pesticide formulation, physical—chemical properties of the pesticide, and properties of the soil surface (48). Under worst-case conditions, 10% or more of the appHed pesticide can leave the edge of the field where it was appHed. 

Benson NU, Etesin UM (2008) Metal contamination of surface water, sediment and Tympa-notonus fuscatus var. radula of Iko River and environmental impact due to Utapete gas flare station, Nigeria. Environmentalist 28 195... 

Because of the high toxicity of pyrethroids to aquatic invertebrates, these organisms are likely to be adversely affected by contamination of surface waters. Such contamination might be expected to have effects at the population level and above, at least in the short term. In one study of a farm pond, cypermethrin was applied aerially, adjacent to the water body (Kedwards et al. 1999a). Changes were observed in the composition of the macroinvertebrate community of the pond that were related to levels of the pyrethroid in the hydrosoil. Diptera were most affected, showing a decline in abundance with increasing cypermethrin concentration. Chironimid larvae first declined and later recovered. 

Nishannon A. Pokja M.S. (1977) Comparative studies ofmicrohial contamination of surfaces hy the contact plate and swab methods. 7,4/7/)/ Bacterial, 42, 53-63. 

Dinitroaniline herbicides have low soil mobility potential. Herbicide residues in the treated field are usually incorporated into the upper layers of the soil mainly as unextractable bound residue therefore, the movement of dinitroaniline herbicides from soil to the water compartment is minimal. Run-off is the principal route, which could lead to the contamination of surface waters. Residue methods were developed to measure the parent concentration in water samples. 

Surface water control is necessary to minimize contamination of surface waters, to prevent surface water infiltration, and to prevent off-site transport of surface waters that have been contaminated. Control of run-on and runoff will accomplish the following ... 

Jinhui L, Huabo D, Pixing S (2011) Heavy metal contamination of surface soil in electronic waste dismantling area site investigation and source-apportionment analysis. Waste Manag... 

Stan HJ, Heberer T, Linkerhagner M (1994) Occurrence of clofibric acid in the aquatic system - is the use in human medical care the source of the contamination of surface ground and drinking water Vom Wasser 83 57-68... 

Pick J, Soderstrom H, Lindberg RH et al (2009) Contamination of surface, ground, and drinking water from pharmaceutical production. Environ Toxicol Chem 28(12) 2522-2527... 

Their widespread environmental presence is most likely to occur from WWTPs point source discharges, which incompletely remove these compounds, leading to the contamination of surface waters, seawaters, groundwater and some drinking waters [31]. 

Astrom et al. (2007) compared the total coliform and E. coli contamination of surface runoff and tile effluent from two no-till field plots one with surface-applied liquid dairy manure and a nonmanure-treated plot. These researchers found greater bacterial populations in surface and tile waters from the manure treated plot, but significant contamination occurred from the nonmanured plot attributed to bird and other wildlife feces. Soupir et al. (2006) examined the release and transport of bacteria from manure applied to pastureland. Using rainfall simulations, they... 

Worldwide production of chemicals has increased dramatically in recent decades, resulting in increased human exposure. This applies not only to workers who manufacture the chemicals and final products but also to those who use the products or are exposed through contamination of surface and ground water and air. 

Radioactive contamination as some background radiation from natural sources, such as radon, occurs in some regions of the world, but there is particular concern over the contamination of surface water and groundwater by radioactive compounds generated by the production of nuclear weapons and by the processing of nuclear fuel. Many of these areas have remained unrecognized because of government secrecy. 

Mills, M.S. and E.M. Thurman (1994a). Reduction of nonpoint source contamination of surface water and groundwater by starch encapsulation of herbicides. Environ. Sci. Technol., 28 73-79. 

The prevention of contamination of surface and ground waters by leaching from hazardous waste is a key of best environmental practice. The dumping of untreated hazardous waste represents a very real threat to a quality of surface and ground waters. This limited and valuable resource must be protected from... 

Bethan, B. Bester, K. Hiihnerfuss, H. Ritnkus, G., Bromocyclen contamination of surface water, waste water and fish from northern Germany, and gas chromatographic chiral separation Chemosphere 1997, 34, 2271-2280. 

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