Industrial wastes from pesticide

Industrial wastes from pesticide and other manufacturing processes merit particular attention. While we know a great deal about the fates of many registered pesticide chemicals, we know very little about the natures and fates of the many products in the immense tonnages of wastes in the dumps of pesticide manufacturers. These compounds will slowly leach from already existing dumps into our waters and soils for hundreds of years. 

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). 

Char from a variety of sources, including coal, is used to produce activated carbon. The two most important uses for activated carbon are for water and wastewater treatment and decolorization. Other uses for activated carbon include the capture of pollutants such as volatile organic compounds (VOCs) and pesticide residues from industrial waste streams. 

As an example of incinerator use in the pesticide industry, one plant operates two incinerators to dispose of wastewater from six pesticide products [7]. They are rated at heat release capacities of 35 and 70 milhon Btu/hour and were designed to dispose of two different wastes. The first primary feed stream consists of approximately 95% organics and 5% water. The second stream consists of approximately 5% organics and 95% water. The energy generated in burning the primary stream is anticipated to vaporize all water in the secondary stream and to oxidize all the organics present. Wastes from two of the six pesticide processes use 0.55% and 4.68% of the incinerator capacity, respectively. The volume of the combined pesticide... 

The use of solvent extraction as a unit process operation is common in the pesticide industry however, it is not widely practised for removing pollutants from waste effluents. Solvent extraction is most effectively applied to segregated process streams as a roughing treatment for removing priority pollutants such as phenols, cyanide, and volatile aromatics [7]. One pesticide plant used a full-scale solvent extraction process for removing 2,4-D from pesticide process wastewaters. As a result, 2,4-D was reduced by 98.9%, from 6710 mg/L to 74.3 mg/L. 

Surface water can be contaminated by point or nonpoint sources. An effluent pipe from an industrial plant or a sewage-treatment plant is an example of a point source a field from which pesticides and fertilizers are carried by rainwater into a river is an example of a nonpoint source. Industrial wastes probably constitute the greatest single pollution problem in soil and water. These contaminants include organic wastes such as solvents, inorganic wastes, such as chromium and many unknown chemicals. Contamination of soil and water results when by-product chemicals are not properly disposed of or conserved. In addition industrial accidents may lead to severe local contamination. For a more in-depth discussion of sources and movements of water pollutants, see Chapter 27. 

Exposure to toxicants from terrestrial sources is very common because of the intimate association between animals and plants that live on the land with soil. Modem agricultural practices call for the application of large quantities of herbicides and other pesticides to plants and soil residues of these substances may readily enter living organisms. Soil is the repository of a variety of air pollutants, especially airborne particles that settle onto soil. Improper disposal of industrial wastes and toxic substances washed from or blown off of hazardous waste sites has contributed to exposure of soil. 

Land uses and potential pollutants. From this will be concluded special ions and components to be analyzed in specialized laboratories (e.g., ions included in relevant fertilizers, relevant pesticides, local landfill and sewage effluents, and industrial wastes—all of which may be site specific). This stage of the investigation is crucial because... 

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. 

Soils and waters affected by emissions from smelters, power plants. Soils and waters affected by mining wastes and by-products. Some playa lake sediments. Soils and dusts derived from naturally As-enriched rocks and sediments. Waters that have leached As from As-rich rocks, soils, and sediments. Pesticides, other industrial chemicals. By-products or wastes from chemical manufacturing or other industrial processes. 

A freshwater stream may look sparkling and clean, but it s probably not safe for drinking. Many rivers and lakes in the United States are polluted. Bacteria and viruses enter water supplies through contamination by sewage and industrial wastes. Wastes from landfills and mines leak into groundwater reservoirs. Pesticides, herbicides, and fertilizers are picked up by rainwater and carried into streams. Streams flow into rivers, and rivers empty into oceans. In addition, coastal cities pump waste directly into the oceans. For this reason, much of the oceans pollution is found along the coasts of continents. 

Aniline is the parent compound of the aromatic amines, which are used in the synthesis of agrochemicals, dyes, and pharmaceuticals. There is a concern that aromatic amines may be released into the environment during production processes or incomplete treatment of industrial waste streams. Additiondly, aromatic amines can enter the environment from the reduction of azo dyes, polynitroaromatic munitions (e.g. TNT), and dinitro herbicides, and from hydrolytic degradation of several classes of pesticides, including the phenylurea, phenylcarbamate, and acylanilide herbicides. 

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