Wastewater pesticide-contaminated

Commercial pesticide applicators are faced with a serious problem in the proper disposal of the large volumes of pesticide contaminated wastewater that are produced during the cleanup of application equipment. Various studies (Whittaker et al. 1982) have reported that the typical agricultural pesticide applicator will produce between 100 and 400 liters of pesticide-contaminated wash water each time he cleans the equipment. For a typical applicator, this amounts to approximately 20,000 liters of waste annually from each piece of equipment (i.e., airplane or truck) that he uses. 

Next several methods of filtering the pesticide contaminated wastewater were evaluated. Particle size filters were Ineffective since many of the particles are microcolloidal in size. Likewise coalescer type filters were generally Inadequate. After studying these filtration techniques, flocculation procedures were... 

Figure 1. Pesticide-contaminated wastewater treatment system for commercial applicators.

Fig. 32. Combined composition interval diagram for pesticide-contaminated wastewater.

EXPOSURE ROUTES Primarily in water and wastewater ingestion(contaminated food) pesticides soil wood leather glue preservatives occupational exposure from production sources of chlorinated phenols or waste burners. 

Rhizodegradation Soils, sediments, land application of wastewater Organic compounds (TPH, PAHs, BTEX, pesticides, chlorinated solvents, PCBs) Phenolics releasers (mulberry, apple, osage orange) Grasses with fibrous roots (rye, fescue, Bermuda) for contaminants 0-3 ft deep Phreatophyte trees for 0-10 ft Aquatic plants for sediments... 

Related to chemical pollution - referring to all kind of contamination (mineral and organic) - there is a clear distinction between point-source pollution and diffuse pollution. It appears that it is easier to take measures for point-source pollution, for instance, the improvement of the wastewater treatment plants, even if the treatments for specific compounds (pesticides, emerging compounds, etc.) still need further research. Measures for diffuse pollution can be more complex because some of them require real political decisions, for instance to interfere on agricultural practices to reduce inorganic and organic fertilisers. 

Pesticides in wastewaters come typically from point sources of contamination such as disposal sites and landfills where industrial or agricultural wastes are buried without any consideration, as well as discharges from industrial effluents from pesticide production plants. Furthermore, nonpoint sources derived from regular agricultural activities, especially in intensive agricultural areas, and accidental spills can also be significant. Urban use of pesticides is also possible in large cities where the use of herbicides and insecticides may result in runoff into the sewers. These sewers in turn may expel pesticides into wastewater treatment plants (WWTPs). 

Artificial Pollutants Organic compounds (chlorinated pesticides, phosphorus-based pesticides, freons) industriai and municipai wastewaters runoff from urban areas and iandfiii erosion of contaminated soiis and sediments atmospheric deposition Toxic effects inciuding birth defects, reproductive faiiure, cancer, and systemic poisoning. 

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